Age-related macular degeneration (AMD) is a multifactorial disease of the macula in which age, smoking, and polygenic susceptibility converge on retinal pigment epithelial stress, dysregulated complement-mediated para-inflammation, outer-retinal extracellular deposits, and photoreceptor degeneration. Advanced dry AMD manifests as geographic atrophy, whereas wet AMD is driven by macular neovascularization with intraretinal or subretinal exudative injury. Both pathways can impair central vision.
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name: Age-Related Macular Degeneration
creation_date: '2025-12-18T17:01:35Z'
updated_date: '2026-02-17T21:53:14Z'
description: >-
Age-related macular degeneration (AMD) is a multifactorial disease of the
macula in which age, smoking, and polygenic susceptibility converge on
retinal pigment epithelial stress, dysregulated complement-mediated
para-inflammation, outer-retinal extracellular deposits, and photoreceptor
degeneration. Advanced dry AMD manifests as geographic atrophy, whereas wet
AMD is driven by macular neovascularization with intraretinal or subretinal
exudative injury. Both pathways can impair central vision.
category: Complex
parents:
- Ophthalmological Disease
disease_term:
preferred_term: age-related macular degeneration
term:
id: MONDO:0005150
label: age-related macular degeneration
has_subtypes:
- name: Dry AMD
display_name: Dry AMD (Atrophic)
description: >-
The non-neovascular form, with gradual outer-retinal degeneration that can
progress to geographic atrophy.
evidence:
- reference: PMID:38928273
reference_title: Immunogenetic and Environmental Factors in Age-Related Macular Disease.
supports: SUPPORT
evidence_source: OTHER
snippet: "This disease can occur in two clinical forms, i.e., dry (progression is slowly and gradually) and exudative (wet, progression is acute and severe), which usually started as dry form."
explanation: The review distinguishes the gradual dry course from the acute exudative form.
- name: Wet AMD
display_name: Wet AMD (Neovascular)
description: >-
The exudative neovascular form, characterized by macular neovascularization
with subretinal and/or intraretinal exudation and potentially rapid visual
decline.
evidence:
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "The late stages of AMD are characterized by outer retinal atrophy, termed geographic atrophy, or neovascularization associated with subretinal and/or intraretinal exudation, termed exudative neovascular AMD."
explanation: The review defines exudative neovascular AMD by neovascularization and retinal exudation.
prevalence:
- population: People aged 55 to 59 years
measure_type: ANNUAL_INCIDENCE
prevalence_class: BAND_1_5_PER_10000
rate_per_100000: 30.0
notes: Annual incidence reported as 0.3 per 1,000 people aged 55 to 59 years.
evidence:
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "The annual incidence of AMD ranges from 0.3 per 1000 in people who are aged 55 to 59 years to 36.7 per 1000 in people aged 90 years or older."
explanation: The lower endpoint converts to 30 incident cases per 100,000 people per year.
- population: People aged 90 years or older
measure_type: ANNUAL_INCIDENCE
prevalence_class: ABOVE_1_IN_1000
rate_per_100000: 3670.0
notes: Annual incidence reported as 36.7 per 1,000 people aged 90 years or older.
evidence:
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "The annual incidence of AMD ranges from 0.3 per 1000 in people who are aged 55 to 59 years to 36.7 per 1000 in people aged 90 years or older."
explanation: The upper endpoint converts to 3,670 incident cases per 100,000 people per year.
progression:
- phase: Early to intermediate extracellular-deposit stage
notes: >-
Outer-retinal extracellular deposits and macular drusen characterize early
disease and predict progression, but drusen are not asserted as a universally
causal lesion because advanced AMD can occur without them.
evidence:
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "AMD occurs when extracellular deposits accumulate in the outer retina, ultimately leading to photoreceptor degeneration and loss of central vision."
explanation: The review places extracellular-deposit accumulation early in the AMD course.
- reference: PMID:38731137
reference_title: Drusen in AMD from the Perspective of Cholesterol Metabolism and Hypoxic Response.
supports: PARTIAL
evidence_source: OTHER
snippet: "Thus, there is the possibility that drusen might be no more than a biomarker of AMD and not a cause of AMD."
explanation: This explicitly limits causal interpretation of drusen despite their prognostic association.
- phase: Advanced geographic-atrophy stage
subtype: Dry AMD
notes: >-
Dry AMD progresses gradually to outer-retinal geographic atrophy with loss
of photoreceptors and supporting retinal tissue.
evidence:
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "The late stages of AMD are characterized by outer retinal atrophy, termed geographic atrophy, or neovascularization associated with subretinal and/or intraretinal exudation, termed exudative neovascular AMD."
explanation: The review identifies geographic atrophy as an advanced AMD endpoint.
- reference: PMID:38928273
reference_title: Immunogenetic and Environmental Factors in Age-Related Macular Disease.
supports: SUPPORT
evidence_source: OTHER
snippet: "This disease can occur in two clinical forms, i.e., dry (progression is slowly and gradually) and exudative (wet, progression is acute and severe), which usually started as dry form."
explanation: The review characterizes dry AMD progression as slow and gradual.
- phase: Exudative neovascular stage
subtype: Wet AMD
notes: >-
Wet AMD may present with acute, severe progression as macular
neovascularization produces intraretinal or subretinal exudation.
evidence:
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "The late stages of AMD are characterized by outer retinal atrophy, termed geographic atrophy, or neovascularization associated with subretinal and/or intraretinal exudation, termed exudative neovascular AMD."
explanation: The review defines the exudative neovascular late-stage pathway.
- reference: PMID:38928273
reference_title: Immunogenetic and Environmental Factors in Age-Related Macular Disease.
supports: SUPPORT
evidence_source: OTHER
snippet: "This disease can occur in two clinical forms, i.e., dry (progression is slowly and gradually) and exudative (wet, progression is acute and severe), which usually started as dry form."
explanation: The review characterizes wet AMD progression as acute and severe.
pathophysiology:
- name: Complement-Pathway Genetic Susceptibility
description: >-
Common variation at CFH and in other complement-pathway genes, including C3
and CFB, alters susceptibility to AMD. CFB is not modeled as uniformly
risk-increasing because human haplotype studies identify both risk and
protective complement-region haplotypes.
biological_scale: MOLECULAR
genes:
- preferred_term: CFH
term:
id: hgnc:4883
label: CFH
- preferred_term: C3
term:
id: hgnc:1318
label: C3
- preferred_term: CFB
term:
id: hgnc:1037
label: CFB
biological_processes:
- preferred_term: complement activation
term:
id: GO:0006956
label: complement activation
evidence:
- reference: DOI:10.3390/biomedicines12071479
reference_title: Genetic Insights into Age-Related Macular Degeneration
supports: PARTIAL
evidence_source: OTHER
snippet: "The common genetic variants linked to AMD are found on chromosome 1q32 (in the complement factor H gene) and 10q26 (age-related maculopathy susceptibility 2 and high-temperature requirement A serine peptidase 1 genes) loci, along with several other risk variants."
explanation: The review supports CFH as a major common AMD susceptibility locus.
- reference: PMID:17634448
reference_title: Complement C3 variant and the risk of age-related macular degeneration.
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "The common functional polymorphism rs2230199 (Arg80Gly) in the C3 gene, corresponding to the electrophoretic variants C3S (slow) and C3F (fast), was strongly associated with age-related macular degeneration in both the English group (603 cases and 350 controls, P=5.9x10(-5)) and the Scottish group (244 cases and 351 controls, P=5.0x10(-5))."
explanation: Replicated case-control association supports C3 as a human AMD susceptibility gene.
- reference: PMID:16518403
reference_title: Variation in factor B (BF) and complement component 2 (C2) genes is associated with age-related macular degeneration.
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Haplotype analyses identify a statistically significant common risk haplotype (H1) and two protective haplotypes."
explanation: Human haplotype data support a mixed risk/protective association at the CFB/C2 region.
downstream:
- target: Complement-Mediated Para-inflammation
description: >-
Complement-pathway susceptibility is placed upstream of dysregulated local
complement activity, but the intervening genotype-to-tissue mechanisms are
incompletely resolved.
causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
intermediate_mechanisms:
- altered regulation of alternative complement activity
evidence:
- reference: PMID:38690727
reference_title: "Complement regulation in the eye: implications for age-related macular degeneration."
supports: PARTIAL
evidence_source: OTHER
snippet: "Dysregulated complement activation contributes to parainflammation, a low level of inflammation triggered by cellular damage that functions to reestablish homeostasis, or outright inflammation that disrupts the visual axis."
explanation: The review supports complement dysregulation as an upstream contributor to ocular para-inflammation, while not resolving variant-specific intermediates.
- name: 10q26 ARMS2/HTRA1 Genetic Susceptibility
description: >-
Common variants at the chromosome 10q26 ARMS2/HTRA1 locus confer AMD
susceptibility. The association is modeled at both candidate genes without
selecting one causal gene or assigning an unsupported downstream molecular
mechanism.
biological_scale: MOLECULAR
genes:
- preferred_term: ARMS2
term:
id: hgnc:32685
label: ARMS2
- preferred_term: HTRA1
term:
id: hgnc:9476
label: HTRA1
evidence:
- reference: DOI:10.3390/biomedicines12071479
reference_title: Genetic Insights into Age-Related Macular Degeneration
supports: SUPPORT
evidence_source: OTHER
snippet: "The common genetic variants linked to AMD are found on chromosome 1q32 (in the complement factor H gene) and 10q26 (age-related maculopathy susceptibility 2 and high-temperature requirement A serine peptidase 1 genes) loci, along with several other risk variants."
explanation: The review identifies the 10q26 ARMS2/HTRA1 locus while leaving causal-gene attribution unresolved.
- name: RPE Oxidative and Lysosomal Stress
description: >-
Age-related photo-oxidative products and reactive oxygen species stress
retinal pigment epithelial cells. Protein-adduct formation and impaired
autophagic flux compromise lysosomal clearance and cellular homeostasis.
biological_scale: CELLULAR
subtypes:
- Dry AMD
cell_types:
- preferred_term: retinal pigment epithelial cell
term:
id: CL:0002586
label: retinal pigment epithelial cell
biological_processes:
- preferred_term: response to oxidative stress
term:
id: GO:0006979
label: response to oxidative stress
modifier: INCREASED
- preferred_term: autophagy
term:
id: GO:0006914
label: autophagy
modifier: DECREASED
evidence:
- reference: DOI:10.3390/antiox13050568
reference_title: Antioxidants and Mechanistic Insights for Managing Dry Age-Related Macular Degeneration
supports: SUPPORT
evidence_source: OTHER
snippet: "The toxic carbonyls due to photo-oxidative degradation of accumulated bisretinoids within lysosomes initiate a series of events including protein adduct formation, impaired autophagy flux, complement activation, and chronic inflammation, which is implicated in dry AMD."
explanation: The review links lysosomal bisretinoid photo-oxidation to adducts, impaired autophagy, complement activation, and inflammation in dry AMD.
- reference: DOI:10.3390/ijms26083463
reference_title: "Role of Oxidative Stress and Inflammation in Age Related Macular Degeneration: Insights into the Retinal Pigment Epithelium (RPE)"
supports: SUPPORT
evidence_source: OTHER
snippet: "A key contributor to disease progression is the excessive accumulation of reactive oxygen species (ROS), which damage retinal pigment epithelium (RPE) cells and disrupt cellular homeostasis."
explanation: The review directly supports ROS-mediated RPE damage and loss of homeostasis.
downstream:
- target: Complement-Mediated Para-inflammation
description: >-
Photo-oxidative lysosomal injury can activate complement and chronic
inflammatory responses through protein-adduct formation and impaired
autophagic clearance.
causal_link_type: INDIRECT_KNOWN_INTERMEDIATES
intermediate_mechanisms:
- photo-oxidative degradation of accumulated bisretinoids
- protein-adduct formation
- impaired autophagic flux
evidence:
- reference: DOI:10.3390/antiox13050568
reference_title: Antioxidants and Mechanistic Insights for Managing Dry Age-Related Macular Degeneration
supports: SUPPORT
evidence_source: OTHER
snippet: "The toxic carbonyls due to photo-oxidative degradation of accumulated bisretinoids within lysosomes initiate a series of events including protein adduct formation, impaired autophagy flux, complement activation, and chronic inflammation, which is implicated in dry AMD."
explanation: This states the known intermediate sequence connecting lysosomal oxidative injury to complement activation and chronic inflammation.
- target: Photoreceptor Degeneration and Outer-Retinal Atrophy
description: >-
RPE injury and disrupted cellular homeostasis impair support of the outer
retina and contribute to photoreceptor degeneration and atrophy.
causal_link_type: INDIRECT_KNOWN_INTERMEDIATES
intermediate_mechanisms:
- RPE cellular damage
- loss of outer-retinal homeostatic support
evidence:
- reference: DOI:10.3390/ijms26083463
reference_title: "Role of Oxidative Stress and Inflammation in Age Related Macular Degeneration: Insights into the Retinal Pigment Epithelium (RPE)"
supports: PARTIAL
evidence_source: OTHER
snippet: "A key contributor to disease progression is the excessive accumulation of reactive oxygen species (ROS), which damage retinal pigment epithelium (RPE) cells and disrupt cellular homeostasis."
explanation: The review supports the RPE injury step, while the compressed edge omits downstream tissue-level intermediates.
- name: Complement-Mediated Para-inflammation
description: >-
Dysregulated complement activation in the posterior eye contributes to
chronic low-grade para-inflammation and, when poorly controlled, inflammatory
tissue injury that can impair retinal integrity.
biological_scale: TISSUE
biological_processes:
- preferred_term: complement activation
term:
id: GO:0006956
label: complement activation
modifier: INCREASED
- preferred_term: inflammatory response
term:
id: GO:0006954
label: inflammatory response
modifier: INCREASED
evidence:
- reference: PMID:38690727
reference_title: "Complement regulation in the eye: implications for age-related macular degeneration."
supports: SUPPORT
evidence_source: OTHER
snippet: "Dysregulated complement activation contributes to parainflammation, a low level of inflammation triggered by cellular damage that functions to reestablish homeostasis, or outright inflammation that disrupts the visual axis."
explanation: The review defines the complement-driven para-inflammatory process in the eye.
- reference: PMID:38690727
reference_title: "Complement regulation in the eye: implications for age-related macular degeneration."
supports: SUPPORT
evidence_source: OTHER
snippet: "Complement dysregulation has been implicated in many ocular diseases, including glaucoma, diabetic retinopathy, and age-related macular degeneration (AMD)."
explanation: The review directly implicates complement dysregulation in AMD.
downstream:
- target: Photoreceptor Degeneration and Outer-Retinal Atrophy
description: >-
Chronic low-grade inflammation can exacerbate AMD tissue injury, although
the complete set of intermediates leading to outer-retinal atrophy remains
unresolved.
causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
intermediate_mechanisms:
- chronic inflammatory impairment of retinal integrity
evidence:
- reference: DOI:10.3390/ijms26083463
reference_title: "Role of Oxidative Stress and Inflammation in Age Related Macular Degeneration: Insights into the Retinal Pigment Epithelium (RPE)"
supports: PARTIAL
evidence_source: OTHER
snippet: "Additionally, immunosenescence and chronic low-grade inflammation exacerbate AMD pathology, further impairing retinal integrity."
explanation: The review supports inflammatory aggravation of retinal injury but does not resolve every step to atrophy.
- name: Outer-Retinal Extracellular Deposit Accumulation
description: >-
Lipid-, complement-, amyloid-, and protein-containing extracellular deposits
accumulate in the outer retina, including drusen beneath the retinal pigment
epithelium. Drusen are a hallmark and progression marker, but are not treated
here as a universally necessary or sufficient cause of advanced AMD.
biological_scale: TISSUE
locations:
- preferred_term: macula lutea
term:
id: UBERON:0000053
label: macula lutea
cell_types:
- preferred_term: retinal pigment epithelial cell
term:
id: CL:0002586
label: retinal pigment epithelial cell
evidence:
- reference: PMID:38731137
reference_title: Drusen in AMD from the Perspective of Cholesterol Metabolism and Hypoxic Response.
supports: SUPPORT
evidence_source: OTHER
snippet: "Drusen comprise a yellowish white substance that accumulates typically under the retinal pigment epithelium (RPE), and their constituents are lipids, complement, amyloid, crystallin, and others."
explanation: The review describes the location and heterogeneous composition of drusen.
- reference: PMID:38731137
reference_title: Drusen in AMD from the Perspective of Cholesterol Metabolism and Hypoxic Response.
supports: PARTIAL
evidence_source: OTHER
snippet: "Thus, there is the possibility that drusen might be no more than a biomarker of AMD and not a cause of AMD."
explanation: The review cautions against assuming that drusen are invariably causal.
downstream:
- target: Photoreceptor Degeneration and Outer-Retinal Atrophy
description: >-
Deposit accumulation precedes photoreceptor degeneration in the canonical
AMD course, but the edge remains partial because drusen may also function as
a biomarker and advanced AMD can occur without them.
causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
intermediate_mechanisms:
- incompletely resolved deposit-associated outer-retinal injury
evidence:
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "AMD occurs when extracellular deposits accumulate in the outer retina, ultimately leading to photoreceptor degeneration and loss of central vision."
explanation: The review places deposit accumulation upstream of photoreceptor degeneration.
- reference: PMID:38731137
reference_title: Drusen in AMD from the Perspective of Cholesterol Metabolism and Hypoxic Response.
supports: PARTIAL
evidence_source: OTHER
snippet: "Thus, there is the possibility that drusen might be no more than a biomarker of AMD and not a cause of AMD."
explanation: This caveat justifies partial support and unknown intermediates for the causal edge.
- target: Macular Drusen
description: Outer-retinal deposit accumulation is clinically observed as macular drusen.
causal_link_type: DIRECT
evidence:
- reference: PMID:38731137
reference_title: Drusen in AMD from the Perspective of Cholesterol Metabolism and Hypoxic Response.
supports: SUPPORT
evidence_source: OTHER
snippet: "Drusen comprise a yellowish white substance that accumulates typically under the retinal pigment epithelium (RPE), and their constituents are lipids, complement, amyloid, crystallin, and others."
explanation: The review directly describes the deposits represented by the macular-drusen phenotype.
- name: Photoreceptor Degeneration and Outer-Retinal Atrophy
description: >-
Degeneration of macular photoreceptors and loss of supporting retinal pigment
epithelium produce outer-retinal atrophy; the advanced dry endpoint is
geographic atrophy.
biological_scale: TISSUE
subtypes:
- Dry AMD
locations:
- preferred_term: macula lutea
term:
id: UBERON:0000053
label: macula lutea
cell_types:
- preferred_term: photoreceptor cell
term:
id: CL:0000210
label: photoreceptor cell
- preferred_term: retinal pigment epithelial cell
term:
id: CL:0002586
label: retinal pigment epithelial cell
biological_processes:
- preferred_term: photoreceptor cell maintenance
term:
id: GO:0045494
label: photoreceptor cell maintenance
modifier: DECREASED
- preferred_term: retina homeostasis
term:
id: GO:0001895
label: retina homeostasis
modifier: DECREASED
evidence:
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "AMD occurs when extracellular deposits accumulate in the outer retina, ultimately leading to photoreceptor degeneration and loss of central vision."
explanation: The review identifies photoreceptor degeneration as a central AMD tissue outcome.
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "The late stages of AMD are characterized by outer retinal atrophy, termed geographic atrophy, or neovascularization associated with subretinal and/or intraretinal exudation, termed exudative neovascular AMD."
explanation: The review identifies outer-retinal geographic atrophy as an advanced AMD endpoint.
downstream:
- target: Macular Geographic Atrophy
description: Advanced outer-retinal atrophy in dry AMD is termed geographic atrophy.
causal_link_type: DIRECT
evidence:
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "The late stages of AMD are characterized by outer retinal atrophy, termed geographic atrophy, or neovascularization associated with subretinal and/or intraretinal exudation, termed exudative neovascular AMD."
explanation: The review directly equates the advanced outer-retinal atrophy endpoint with geographic atrophy.
- target: Central Vision Loss
description: Macular photoreceptor degeneration impairs central vision.
causal_link_type: DIRECT
evidence:
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "AMD occurs when extracellular deposits accumulate in the outer retina, ultimately leading to photoreceptor degeneration and loss of central vision."
explanation: The review directly connects photoreceptor degeneration with central vision loss.
- target: Reduced Contrast Sensitivity
description: >-
Outer-retinal dysfunction can reduce contrast sensitivity, particularly in
intermediate AMD and under low-light conditions.
causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
intermediate_mechanisms:
- impaired macular visual processing under low luminance
evidence:
- reference: PMID:34412522
reference_title: Contrast Sensitivity in Early to Intermediate Age-Related Macular Degeneration (AMD).
supports: PARTIAL
evidence_source: HUMAN_CLINICAL
snippet: "Group differences in CS were only found in intermediate AMD patients. The loss in CS increased for the intermediate AMD patients under low light levels."
explanation: The human study supports reduced contrast sensitivity in intermediate AMD but not in all stages.
- name: VEGF-Driven Macular Neovascularization
description: >-
Localized ischemia and inflammation increase VEGF production by retinal
pigment epithelial and/or Mueller cells, promoting abnormal macular vascular
growth from choriocapillaris or retinal microvascular sources.
biological_scale: TISSUE
subtypes:
- Wet AMD
locations:
- preferred_term: macula lutea
term:
id: UBERON:0000053
label: macula lutea
cell_types:
- preferred_term: retinal pigment epithelial cell
term:
id: CL:0002586
label: retinal pigment epithelial cell
- preferred_term: Mueller cell
term:
id: CL:0000636
label: Mueller cell
- preferred_term: retinal blood vessel endothelial cell
term:
id: CL:0002585
label: retinal blood vessel endothelial cell
biological_processes:
- preferred_term: vascular endothelial growth factor production
term:
id: GO:0010573
label: vascular endothelial growth factor production
modifier: INCREASED
- preferred_term: angiogenesis
term:
id: GO:0001525
label: angiogenesis
modifier: INCREASED
evidence:
- reference: PMID:39222802
reference_title: Macular neovascularization.
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Neovascularization of the macula, a common complication of many chorioretinal diseases such as neovascular age-related macular degeneration, polypoidal choroidal vasculopathy, and pathologic myopia, results from increased synthesis of vascular endothelial growth factor (VEGF) by the retinal pigment epithelium and/or Müller cells because of localized ischemia and inflammation."
explanation: The review identifies localized ischemia/inflammation, RPE or Müller-cell VEGF production, and macular neovascularization.
downstream:
- target: Subretinal/Intraretinal Exudative Injury
description: Fragile macular neovascular complexes produce intraretinal thickening and subretinal exudation.
causal_link_type: DIRECT
evidence:
- reference: PMID:39222802
reference_title: Macular neovascularization.
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "MNV frequently appears as a grey-green macular lesion with overlying intraretinal thickening and/or subretinal exudation, causing metamorphopsia, reduced central vision, relative central scotoma, decreased reading speed, and problems with color recognition."
explanation: The review directly describes exudative retinal injury overlying MNV.
- target: Choroidal Neovascularization
description: >-
Neovascular wet AMD includes abnormal vessels arising from the
choriocapillaris and presenting clinically as choroidal neovascularization.
causal_link_type: DIRECT
evidence:
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "The late stages of AMD are characterized by outer retinal atrophy, termed geographic atrophy, or neovascularization associated with subretinal and/or intraretinal exudation, termed exudative neovascular AMD."
explanation: The review supports neovascularization as the defining lesion of wet AMD.
- name: Subretinal/Intraretinal Exudative Injury
description: >-
Macular neovascular lesions disrupt outer-retinal architecture through
intraretinal thickening and subretinal or intraretinal exudation, producing
distortion, central field defects, and central visual loss.
biological_scale: TISSUE
subtypes:
- Wet AMD
locations:
- preferred_term: macula lutea
term:
id: UBERON:0000053
label: macula lutea
evidence:
- reference: PMID:39222802
reference_title: Macular neovascularization.
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "MNV frequently appears as a grey-green macular lesion with overlying intraretinal thickening and/or subretinal exudation, causing metamorphopsia, reduced central vision, relative central scotoma, decreased reading speed, and problems with color recognition."
explanation: The review links the exudative lesion to central visual symptoms and field defects.
downstream:
- target: Metamorphopsia
description: Exudative disruption of macular architecture distorts central vision.
causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
intermediate_mechanisms:
- distortion of central retinal architecture
evidence:
- reference: PMID:39222802
reference_title: Macular neovascularization.
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "MNV frequently appears as a grey-green macular lesion with overlying intraretinal thickening and/or subretinal exudation, causing metamorphopsia, reduced central vision, relative central scotoma, decreased reading speed, and problems with color recognition."
explanation: The review explicitly links the exudative MNV lesion to metamorphopsia.
- target: Central Scotoma
description: Exudative macular injury can produce a relative central scotoma.
causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
intermediate_mechanisms:
- localized macular dysfunction
evidence:
- reference: PMID:39222802
reference_title: Macular neovascularization.
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "MNV frequently appears as a grey-green macular lesion with overlying intraretinal thickening and/or subretinal exudation, causing metamorphopsia, reduced central vision, relative central scotoma, decreased reading speed, and problems with color recognition."
explanation: The review explicitly links the exudative MNV lesion to relative central scotoma.
- target: Central Vision Loss
description: Exudative damage to the macula reduces central vision.
causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
intermediate_mechanisms:
- disruption of central retinal structure and function
evidence:
- reference: PMID:39222802
reference_title: Macular neovascularization.
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "MNV frequently appears as a grey-green macular lesion with overlying intraretinal thickening and/or subretinal exudation, causing metamorphopsia, reduced central vision, relative central scotoma, decreased reading speed, and problems with color recognition."
explanation: The review explicitly links the exudative MNV lesion to reduced central vision.
phenotypes:
- name: Central Vision Loss
category: Eye
description: Progressive or acute loss of central visual function from macular outer-retinal injury.
phenotype_term:
preferred_term: Central vision loss
term:
id: HP:0000572
label: Visual loss
evidence:
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "AMD occurs when extracellular deposits accumulate in the outer retina, ultimately leading to photoreceptor degeneration and loss of central vision."
explanation: The review identifies central vision loss as a clinical consequence of AMD degeneration.
- name: Metamorphopsia
category: Eye
subtype: Wet AMD
description: Distortion of visual images caused by neovascular exudative macular injury.
phenotype_term:
preferred_term: Metamorphopsia
term:
id: HP:0012508
label: Metamorphopsia
evidence:
- reference: PMID:39222802
reference_title: Macular neovascularization.
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "MNV frequently appears as a grey-green macular lesion with overlying intraretinal thickening and/or subretinal exudation, causing metamorphopsia, reduced central vision, relative central scotoma, decreased reading speed, and problems with color recognition."
explanation: The review directly reports metamorphopsia with exudative MNV.
- name: Central Scotoma
category: Eye
subtype: Wet AMD
description: A central visual-field defect associated with macular neovascular injury.
phenotype_term:
preferred_term: Central scotoma
term:
id: HP:0000603
label: Central scotoma
evidence:
- reference: PMID:39222802
reference_title: Macular neovascularization.
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "MNV frequently appears as a grey-green macular lesion with overlying intraretinal thickening and/or subretinal exudation, causing metamorphopsia, reduced central vision, relative central scotoma, decreased reading speed, and problems with color recognition."
explanation: The review directly reports relative central scotoma with exudative MNV.
- name: Reduced Contrast Sensitivity
category: Eye
description: Reduced contrast discrimination, especially in intermediate AMD under low-light conditions.
phenotype_term:
preferred_term: Reduced contrast sensitivity
term:
id: HP:0032036
label: Reduced contrast sensitivity
evidence:
- reference: PMID:34412522
reference_title: Contrast Sensitivity in Early to Intermediate Age-Related Macular Degeneration (AMD).
supports: PARTIAL
evidence_source: HUMAN_CLINICAL
snippet: "Group differences in CS were only found in intermediate AMD patients. The loss in CS increased for the intermediate AMD patients under low light levels."
explanation: The study supports the phenotype in intermediate AMD while showing that it does not discriminate early AMD.
- name: Macular Drusen
category: Eye
description: Extracellular macular deposits, typically beneath the retinal pigment epithelium.
diagnostic: true
phenotype_term:
preferred_term: Macular drusen
term:
id: HP:0030499
label: Macular drusen
evidence:
- reference: PMID:38731137
reference_title: Drusen in AMD from the Perspective of Cholesterol Metabolism and Hypoxic Response.
supports: SUPPORT
evidence_source: OTHER
snippet: "In fact, it is well established that drusen are the hallmark of precursor lesion of AMD and a major risk factor for AMD progression mainly based on their size and number."
explanation: The review supports macular drusen as a hallmark precursor lesion and progression marker.
- name: Macular Geographic Atrophy
category: Eye
subtype: Dry AMD
description: Advanced dry AMD with geographic outer-retinal atrophy in the macula.
diagnostic: true
phenotype_term:
preferred_term: Macular geographic atrophy
term:
id: HP:0031609
label: Macular geographic atrophy
evidence:
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "The late stages of AMD are characterized by outer retinal atrophy, termed geographic atrophy, or neovascularization associated with subretinal and/or intraretinal exudation, termed exudative neovascular AMD."
explanation: The review defines geographic atrophy as an advanced outer-retinal AMD phenotype.
- name: Choroidal Neovascularization
category: Eye
subtype: Wet AMD
description: Pathologic neovascular growth in the macula characteristic of neovascular AMD.
diagnostic: true
phenotype_term:
preferred_term: Choroidal neovascularization
term:
id: HP:0011506
label: Choroidal neovascularization
evidence:
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "The late stages of AMD are characterized by outer retinal atrophy, termed geographic atrophy, or neovascularization associated with subretinal and/or intraretinal exudation, termed exudative neovascular AMD."
explanation: The review supports neovascularization as the defining lesion of wet AMD.
imaging_findings:
- name: Macular neovascularization with intraretinal thickening and subretinal exudation on OCT
modality: OCT
imaging_finding_term:
preferred_term: Macular neovascularization with intraretinal thickening and subretinal exudation
description: >-
OCT can show a focal macular neovascular lesion with overlying intraretinal
thickening and/or subretinal exudation, supporting diagnosis of wet AMD.
located_in:
preferred_term: macula lutea
term:
id: UBERON:0000053
label: macula lutea
spatial_extent: FOCAL
phenotype_term:
preferred_term: Choroidal neovascularization
term:
id: HP:0011506
label: Choroidal neovascularization
diagnostic: true
subtype: Wet AMD
evidence:
- reference: PMID:39222802
reference_title: Macular neovascularization.
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "MNV frequently appears as a grey-green macular lesion with overlying intraretinal thickening and/or subretinal exudation, causing metamorphopsia, reduced central vision, relative central scotoma, decreased reading speed, and problems with color recognition."
explanation: The review describes the focal macular lesion and its exudative imaging appearance.
- reference: PMID:39222802
reference_title: Macular neovascularization.
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Multimodal imaging with optical coherence tomography (OCT), OCT angiography, dye-based angiographies, fundus autofluorescence, and multiwavelength photography help establish the diagnosis and aid in selecting an appropriate treatment."
explanation: The review supports OCT as a diagnostic modality for macular neovascularization.
genetic:
- name: CFH
gene_term:
preferred_term: CFH
term:
id: hgnc:4883
label: CFH
association: Common polygenic susceptibility locus
relationship_type: SUSCEPTIBILITY
variant_origin: GERMLINE
evidence:
- reference: DOI:10.3390/biomedicines12071479
reference_title: Genetic Insights into Age-Related Macular Degeneration
supports: SUPPORT
evidence_source: OTHER
snippet: "The common genetic variants linked to AMD are found on chromosome 1q32 (in the complement factor H gene) and 10q26 (age-related maculopathy susceptibility 2 and high-temperature requirement A serine peptidase 1 genes) loci, along with several other risk variants."
explanation: The review identifies common CFH-region variants as an AMD susceptibility locus.
- name: ARMS2
gene_term:
preferred_term: ARMS2
term:
id: hgnc:32685
label: ARMS2
association: Common susceptibility locus at 10q26
relationship_type: SUSCEPTIBILITY
variant_origin: GERMLINE
notes: >-
The 10q26 association spans ARMS2 and HTRA1; this record does not resolve
which gene or downstream mechanism is causal.
evidence:
- reference: DOI:10.3390/biomedicines12071479
reference_title: Genetic Insights into Age-Related Macular Degeneration
supports: SUPPORT
evidence_source: OTHER
snippet: "The common genetic variants linked to AMD are found on chromosome 1q32 (in the complement factor H gene) and 10q26 (age-related maculopathy susceptibility 2 and high-temperature requirement A serine peptidase 1 genes) loci, along with several other risk variants."
explanation: The review identifies ARMS2 at the common 10q26 AMD susceptibility locus.
- name: HTRA1
gene_term:
preferred_term: HTRA1
term:
id: hgnc:9476
label: HTRA1
association: Common susceptibility locus at 10q26
relationship_type: SUSCEPTIBILITY
variant_origin: GERMLINE
notes: >-
The 10q26 association spans ARMS2 and HTRA1; this record does not resolve
which gene or downstream mechanism is causal.
evidence:
- reference: DOI:10.3390/biomedicines12071479
reference_title: Genetic Insights into Age-Related Macular Degeneration
supports: SUPPORT
evidence_source: OTHER
snippet: "The common genetic variants linked to AMD are found on chromosome 1q32 (in the complement factor H gene) and 10q26 (age-related maculopathy susceptibility 2 and high-temperature requirement A serine peptidase 1 genes) loci, along with several other risk variants."
explanation: The review identifies HTRA1 at the common 10q26 AMD susceptibility locus.
- name: C3
gene_term:
preferred_term: C3
term:
id: hgnc:1318
label: C3
association: Common complement-pathway susceptibility variant
relationship_type: SUSCEPTIBILITY
variant_origin: GERMLINE
evidence:
- reference: PMID:17634448
reference_title: Complement C3 variant and the risk of age-related macular degeneration.
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "The common functional polymorphism rs2230199 (Arg80Gly) in the C3 gene, corresponding to the electrophoretic variants C3S (slow) and C3F (fast), was strongly associated with age-related macular degeneration in both the English group (603 cases and 350 controls, P=5.9x10(-5)) and the Scottish group (244 cases and 351 controls, P=5.0x10(-5))."
explanation: Replication in two human case-control cohorts supports C3 susceptibility.
- name: CFB
gene_term:
preferred_term: CFB
term:
id: hgnc:1037
label: CFB
association: Complement-region susceptibility with both risk and protective haplotypes
relationship_type: SUSCEPTIBILITY
variant_origin: GERMLINE
notes: >-
The CFB/C2 region contains a common risk haplotype as well as protective
haplotypes; CFB is therefore not represented as uniformly risk-increasing.
evidence:
- reference: PMID:16518403
reference_title: Variation in factor B (BF) and complement component 2 (C2) genes is associated with age-related macular degeneration.
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Haplotype analyses identify a statistically significant common risk haplotype (H1) and two protective haplotypes."
explanation: Human haplotype analysis supports a mixed risk/protective association at the CFB/C2 locus.
- reference: PMID:16518403
reference_title: Variation in factor B (BF) and complement component 2 (C2) genes is associated with age-related macular degeneration.
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "The L9H variant of BF and the E318D variant of C2 (H10), as well as a variant in intron 10 of C2 and the R32Q variant of BF (H7), confer a significantly reduced risk of AMD (odds ratio = 0.45 and 0.36, respectively)."
explanation: The protective BF/CFB haplotypes prevent oversimplifying the locus as risk-only.
environmental:
- name: Older Age
presence: Risk factor
description: AMD incidence rises steeply across older age strata.
evidence:
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Older age, genetic factors, and environmental factors, such as cigarette smoking, are associated with development of AMD."
explanation: The review identifies older age as an AMD-associated factor.
- name: Cigarette Smoking
presence: Risk factor
description: Long-term cigarette smoking is associated with higher AMD incidence.
exposure_term:
preferred_term: exposure to cigarette smoking
term:
id: ECTO:0100003
label: exposure to cigarette smoking
evidence:
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Long-term prospective cohort studies show a significantly higher AMD incidence in people who smoke more than 20 cigarettes per day compared with people who never smoked."
explanation: Prospective cohort evidence summarized in the review supports cigarette smoking as an environmental risk factor.
treatments:
- name: Intravitreal Anti-VEGF Therapy
action_category: THERAPEUTIC
description: >-
Intravitreal VEGF inhibition is first-line therapy for exudative neovascular
AMD and preserves visual acuity relative to sham treatment.
treatment_term:
preferred_term: Pharmacotherapy
term:
id: NCIT:C15986
label: Pharmacotherapy
therapeutic_agent:
- preferred_term: Angiogenesis inhibitor
term:
id: NCIT:C1742
label: Angiogenesis Inhibitor
target_phenotypes:
- preferred_term: Choroidal Neovascularization
term:
id: HP:0011506
label: Choroidal neovascularization
target_mechanisms:
- target: VEGF-Driven Macular Neovascularization
treatment_effect: INHIBITS
description: Anti-VEGF agents inhibit the VEGF-dependent neovascular pathway.
evidence:
- reference: PMID:39222802
reference_title: Macular neovascularization.
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "The standard of care for MNV is usually intravitreal anti-vascular endothelial growth factor injections, though thermal laser photocoagulation, verteporfin photodynamic therapy, and vitreoretinal surgery are occasionally used."
explanation: The review identifies intravitreal anti-VEGF therapy as standard care for MNV.
evidence:
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Intravitreally administered anti-VEGF treatment is first-line therapy for exudative neovascular AMD."
explanation: The review identifies intravitreal anti-VEGF as first-line wet-AMD therapy.
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "In exudative neovascular AMD, 94.6% of patients receiving monthly intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections experience less than a 15-letter visual acuity loss after 12 months compared with 62.2% receiving sham treatment."
explanation: The review reports controlled comparative evidence for preservation of visual acuity.
- name: AREDS/AREDS2 Nutritional Supplementation
action_category: THERAPEUTIC
description: >-
High-dose antioxidant vitamins, carotenoids, and zinc reduce progression to
late-stage AMD in appropriately selected patients; this is not modeled as a
direct correction of one molecular node.
treatment_term:
preferred_term: nutritional supplementation
term:
id: NCIT:C15433
label: Nutritional Support
evidence:
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Individuals with AMD who take nutritional supplements consisting of high-dose vitamin C, vitamin E, carotenoids, and zinc have a 20% probability to progress to late-stage AMD at 5 years vs a 28% probability for those taking a placebo."
explanation: The review reports lower five-year progression with AREDS-type supplementation than placebo.
- name: Complement-Inhibitor Therapy for Geographic Atrophy
action_category: THERAPEUTIC
description: >-
Intravitreal complement inhibitors reduce geographic-atrophy lesion growth,
but the cited network meta-analysis found no significant BCVA benefit and
identified an increased macular-neovascularization risk with monthly
pegcetacoplan.
treatment_term:
preferred_term: Pharmacotherapy
term:
id: NCIT:C15986
label: Pharmacotherapy
therapeutic_agent:
- preferred_term: Complement inhibitor
term:
id: NCIT:C199456
label: Complement Inhibitor
target_phenotypes:
- preferred_term: Macular Geographic Atrophy
term:
id: HP:0031609
label: Macular geographic atrophy
target_mechanisms:
- target: Complement-Mediated Para-inflammation
treatment_effect: INHIBITS
description: Complement inhibitors pharmacologically suppress the complement arm implicated in atrophic AMD.
evidence:
- reference: DOI:10.3389/fphar.2024.1410172
reference_title: "Efficacy and safety of complement inhibitors in patients with geographic atrophy associated with age-related macular degeneration: a network meta-analysis of randomized controlled trials"
supports: PARTIAL
evidence_source: HUMAN_CLINICAL
snippet: "Clinical trials in recent years have shown significant effectiveness of complement inhibitors for geographic atrophy (GA) treatment."
explanation: The clinical-trial synthesis supports pharmacologic inhibition of the complement arm as a treatment strategy for GA.
evidence:
- reference: DOI:10.3389/fphar.2024.1410172
reference_title: "Efficacy and safety of complement inhibitors in patients with geographic atrophy associated with age-related macular degeneration: a network meta-analysis of randomized controlled trials"
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Comparison with sham and SUCRA analysis showed that avacincaptad pegol 2 mg (MD: −0.58, 95% CrI: −0.97 to −0.18, SUCRA: 93.55), pegcetacoplan monthly (MD: −0.38, 95% CrI: −0.57 to −0.20, SUCRA: 81.37), and pegcetacoplan every other month (MD: −0.30, 95% CrI: −0.49 to −0.11, SUCRA: 70.16) have significant changes in GA lesion reduction."
explanation: The network meta-analysis directly reports reduced geographic-atrophy lesion growth relative to sham.
- reference: DOI:10.3389/fphar.2024.1410172
reference_title: "Efficacy and safety of complement inhibitors in patients with geographic atrophy associated with age-related macular degeneration: a network meta-analysis of randomized controlled trials"
supports: PARTIAL
evidence_source: HUMAN_CLINICAL
snippet: "No treatments showed significant changes in BCVA and SAE compared with sham. Pegcetacoplan monthly (OR: 4.30, 95% CrI: 1.48–16.72) increased the risk of MNV."
explanation: The meta-analysis limits the benefit claim to anatomy and records the absence of BCVA improvement and an MNV safety signal.
- name: Verteporfin Photodynamic Therapy
action_category: THERAPEUTIC
description: Verteporfin photodynamic therapy is an occasional treatment option for selected macular neovascular lesions.
treatment_term:
preferred_term: photodynamic therapy
term:
id: NCIT:C15300
label: Photodynamic Therapy
therapeutic_agent:
- preferred_term: verteporfin
term:
id: CHEBI:32293
label: verteporfin
target_phenotypes:
- preferred_term: Choroidal Neovascularization
term:
id: HP:0011506
label: Choroidal neovascularization
evidence:
- reference: PMID:39222802
reference_title: Macular neovascularization.
supports: PARTIAL
evidence_source: HUMAN_CLINICAL
snippet: "The standard of care for MNV is usually intravitreal anti-vascular endothelial growth factor injections, though thermal laser photocoagulation, verteporfin photodynamic therapy, and vitreoretinal surgery are occasionally used."
explanation: The review supports verteporfin photodynamic therapy as an occasional rather than standard MNV treatment.
- name: Low-Vision Rehabilitation
action_category: THERAPEUTIC
description: Low-vision aids and rehabilitation are recommended for geographic-atrophy-related visual loss.
treatment_term:
preferred_term: Rehabilitation
term:
id: NCIT:C15315
label: Rehabilitation
target_phenotypes:
- preferred_term: Central Vision Loss
term:
id: HP:0000572
label: Visual loss
evidence:
- reference: PMID:37455795
reference_title: Rehabilitation Methods for Patients with Geographic Atrophy due to Age-Related Macular Degeneration and Effects of Rehabilitation on Quality of Life.
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Low vision patients with ARMD-related geographic atrophy should meet with low vision aids as soon as possible and should be included in low vision rehabilitation programs."
explanation: A human rehabilitation study supports early provision of low-vision aids and rehabilitation for geographic atrophy.
diagnosis:
- name: Clinical Ophthalmic Examination
description: >-
Primary diagnosis uses clinical ophthalmic examination with a special lens
that focuses slit-lamp light through the pupil.
diagnosis_term:
preferred_term: clinical assessment
term:
id: NCIT:C124351
label: Clinical Evaluation
evidence:
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "AMD is diagnosed primarily with clinical examination that includes a special lens that focuses light of the slit lamp through the pupil."
explanation: The review describes the primary clinical ophthalmic examination used to diagnose AMD.
- name: Optical Coherence Tomography
description: OCT identifies and characterizes exudative neovascular AMD and associated retinal fluid or thickening.
diagnosis_term:
preferred_term: optical coherence tomography
term:
id: NCIT:C20828
label: Optical Coherence Tomography
evidence:
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Exudative neovascular AMD is best identified using angiography and by optical coherence tomography."
explanation: The review identifies OCT as a preferred diagnostic modality for exudative neovascular AMD.
- name: Angiography
description: Dye-based or OCT angiography delineates macular neovascularization in wet AMD.
diagnosis_term:
preferred_term: angiography
term:
id: NCIT:C190556
label: Angiography
evidence:
- reference: PMID:38193957
reference_title: "Age-Related Macular Degeneration: A Review."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Exudative neovascular AMD is best identified using angiography and by optical coherence tomography."
explanation: The review identifies angiography as a preferred diagnostic modality for exudative neovascular AMD.
classifications:
harrisons_chapter:
- classification_value: NEUROLOGIC
references:
- reference: PMID:38193957
title: "Age-Related Macular Degeneration: A Review."
findings: []
- reference: PMID:38690727
title: "Complement regulation in the eye: implications for age-related macular degeneration."
findings: []
- reference: PMID:38731137
title: Drusen in AMD from the Perspective of Cholesterol Metabolism and Hypoxic Response.
findings: []
- reference: PMID:38928273
title: Immunogenetic and Environmental Factors in Age-Related Macular Disease.
findings: []
- reference: PMID:39222802
title: Macular neovascularization.
findings: []
- reference: PMID:34412522
title: Contrast Sensitivity in Early to Intermediate Age-Related Macular Degeneration (AMD).
findings: []
- reference: PMID:17634448
title: Complement C3 variant and the risk of age-related macular degeneration.
findings: []
- reference: PMID:16518403
title: Variation in factor B (BF) and complement component 2 (C2) genes is associated with age-related macular degeneration.
findings: []
- reference: PMID:37455795
title: Rehabilitation Methods for Patients with Geographic Atrophy due to Age-Related Macular Degeneration and Effects of Rehabilitation on Quality of Life.
findings: []
- reference: DOI:10.3390/antiox13050568
title: Antioxidants and Mechanistic Insights for Managing Dry Age-Related Macular Degeneration
findings: []
- reference: DOI:10.3390/ijms26083463
title: "Role of Oxidative Stress and Inflammation in Age Related Macular Degeneration: Insights into the Retinal Pigment Epithelium (RPE)"
findings: []
- reference: DOI:10.3390/biomedicines12071479
title: Genetic Insights into Age-Related Macular Degeneration
findings: []
- reference: DOI:10.3389/fphar.2024.1410172
title: "Efficacy and safety of complement inhibitors in patients with geographic atrophy associated with age-related macular degeneration: a network meta-analysis of randomized controlled trials"
findings: []
Disease Pathophysiology Research Report
Target Disease - Disease Name: Age-Related Macular Degeneration (AMD) - MONDO ID: MONDO_0002469 (age-related macular degeneration) - Category: Complex
Pathophysiology description (current understanding) AMD is a multifactorial neurodegenerative disease of the macula characterized by dysfunction of the retinal pigment epithelium (RPE), photoreceptor loss, and alterations at the RPE–Bruch’s membrane–choriocapillaris interface. Central mechanisms include dysregulated complement activation with local para-inflammation, innate immune sensing and inflammasome activation, chronic oxidative stress and mitochondrial dysfunction, impaired autophagy–lysosomal flux with lipofuscin/bisretinoid accumulation, dysregulated lipid/cholesterol metabolism and extracellular deposit formation (drusen and basal deposits), and in neovascular AMD, VEGF-driven angiogenesis. A 2024 review emphasizes the eye as “a complement dysregulation hotspot,” noting that chronic low-level complement activation is normally controlled by intraocular regulators (MCP/CD46, DAF/CD55, CD59) but becomes pathogenic at the RPE–Bruch’s membrane interface where drusen/basal deposits form (with complement components present) (Wilke & Apte 2024, JCI; https://doi.org/10.1172/JCI178296) (wilke2024complementregulationin pages 9-10). Drusen are lipid- and complement-rich deposits between RPE and Bruch’s membrane; their size/type correlate with progression to geographic atrophy (GA) or choroidal neovascularization (Basyal 2024; Antioxidants; https://doi.org/10.3390/antiox13050568) (basyal2024antioxidantsandmechanistic pages 2-4). Dysregulated cholesterol metabolism and oxidized cholesterol contribute to drusen biogenesis; drusen contain oxidized lipids and complement, linking lipid metabolism to complement activation (Ban 2024; J Clin Med; https://doi.org/10.3390/jcm13092608) (ban2024druseninamd pages 4-5). Innate immune activation via pattern-recognition pathways converges on the NLRP3 inflammasome, leading to caspase‑1 activation and IL‑1β/IL‑18 maturation, implicated in RPE injury and para-inflammation (Hernández 2025; IJMS; https://doi.org/10.3390/ijms26083463) (hernandez2025roleofoxidative pages 8-10, hernandez2025roleofoxidative pages 6-8). Oxidative stress and mitochondrial dysfunction in RPE are central drivers of damage and impaired phagocytosis; photo-oxidative byproducts (bisretinoids such as A2E) accumulate in lipofuscin and perturb autophagy–lysosome function, promoting complement activation and chronic inflammation (Basyal 2024; https://doi.org/10.3390/antiox13050568) (basyal2024antioxidantsandmechanistic pages 2-4). In neovascular AMD, hypoxia/inflammation induce VEGF signaling that drives choroidal neovascularization; anti‑VEGF therapies target this pathway clinically (Ong 2024; Medicina; https://doi.org/10.3390/medicina60101647) (ong2024agerelatedmaculardegeneration pages 5-7).
Recent developments and latest research (prioritized 2023–2024) - Complement system and regulation: JCI 2024 review details intraocular complement regulation and genetic risk at CFH/CFHR/C3 loci and frames complement-targeted therapeutics for GA (Wilke & Apte 2024; https://doi.org/10.1172/JCI178296) (wilke2024complementregulationin pages 9-10). A 2024 J Clin Med review connects drusen cholesterol/oxidized lipids with complement activation and highlights GA treatment by complement inhibition (Ban 2024; https://doi.org/10.3390/jcm13092608) (ban2024druseninamd pages 4-5). - Genetics and risk architecture: 2024 Biomedicines review synthesizes >40 AMD loci spanning complement (CFH, C3, CFI, C2/CFB), lipid transport (APOE, ABCA1, LIPC, CETP), ECM (TIMP3/MMPs), and angiogenesis (VEGFA), supporting the mechanistic axes now targeted clinically (Bhumika 2024; https://doi.org/10.3390/biomedicines12071479) (bhumika2024geneticinsightsinto pages 3-4, bhumika2024geneticinsightsinto pages 10-11). - Oxidative stress/mitochondria and inflammasome: 2025 IJMS review integrates oxidative stress, RPE dysfunction, complement anaphylatoxins (C3/C5), and NLRP3 inflammasome-mediated IL‑1β/IL‑18 release as contributors to AMD progression (Hernández 2025; https://doi.org/10.3390/ijms26083463) (hernandez2025roleofoxidative pages 8-10, hernandez2025roleofoxidative pages 6-8). - Translational complement therapies in GA: 2024 AJO perspective reviews FDA approvals of pegcetacoplan (C3 inhibitor) and avacincaptad pegol (C5 inhibitor) for GA, summarizing the pivotal trials and the need for further optimization (Csaky 2024; https://doi.org/10.1016/j.ajo.2024.02.021) (wilke2024complementregulationin pages 9-10). A 2024 network meta-analysis of 10 RCTs (n=4,405) ranked avacincaptad pegol 2 mg and pegcetacoplan (monthly/q2mo) as significantly reducing 12‑month GA lesion growth vs sham, with no BCVA gains and an increased macular neovascularization risk signal for monthly pegcetacoplan (Wang 2024; Front Pharmacol; https://doi.org/10.3389/fphar.2024.1410172) (wilke2024complementregulationin pages 9-10).
Current applications and real-world implementations - Anti‑VEGF for neovascular AMD: VEGF‑A/VEGFR2 pathway inhibition (bevacizumab, ranibizumab, aflibercept, brolucizumab, faricimab) remains the standard of care for CNV secondary to AMD, directly targeting angiogenesis (Ong 2024; https://doi.org/10.3390/medicina60101647) (ong2024agerelatedmaculardegeneration pages 5-7). - Complement inhibition for GA: Clinical approvals in 2023 established the first disease-modifying therapies for atrophic AMD. Pegcetacoplan (C3 inhibitor) and avacincaptad pegol (C5 inhibitor) slowed GA lesion expansion; however, randomized trials did not show consistent visual acuity benefit and revealed a macular neovascularization safety signal with monthly pegcetacoplan dosing (Csaky 2024, AJO; https://doi.org/10.1016/j.ajo.2024.02.021; Wang 2024, Front Pharmacol; https://doi.org/10.3389/fphar.2024.1410172) (wilke2024complementregulationin pages 9-10). Real‑world adoption is expanding via ongoing phase 4 and observational programs registered on ClinicalTrials.gov (not directly cited here as a context ID) and summarized in the approvals review (wilke2024complementregulationin pages 9-10).
Expert opinions and analysis from authoritative sources - Complement-centric paradigm: The JCI 2024 review underscores that complement dysregulation is central to posterior segment parainflammation in AMD and emphasizes intraocular complement regulation and genetic architecture as mechanistic rationale for C3/C5 targeted therapies (Wilke & Apte 2024; https://doi.org/10.1172/JCI178296) (wilke2024complementregulationin pages 9-10). Genetics reviews further argue that complement and lipid loci together explain substantial risk and map directly onto drusen biochemistry and choriocapillaris injury (Bhumika 2024; https://doi.org/10.3390/biomedicines12071479) (bhumika2024geneticinsightsinto pages 3-4, bhumika2024geneticinsightsinto pages 10-11). The network meta-analysis provides comparative efficacy/safety insights guiding agent choice in GA (Wang 2024; https://doi.org/10.3389/fphar.2024.1410172) (wilke2024complementregulationin pages 9-10).
Relevant statistics and data from recent studies - Drusen composition and risk: Drusen are enriched in lipids (including oxidized cholesterol), apolipoprotein E, and complement proteins; drusen size and number stratify progression risk to GA/CNV (Basyal 2024; https://doi.org/10.3390/antiox13050568) (basyal2024antioxidantsandmechanistic pages 2-4); (Ban 2024; https://doi.org/10.3390/jcm13092608) (ban2024druseninamd pages 4-5). - Genetic architecture: Reviews summarize >40 risk loci and strong contributions from CFH, C3, CFI and the 10q26 ARMS2/HTRA1 region; APOE allele-specific effects and lipid transport genes (ABCA1, LIPC, CETP) are implicated in drusen biology (Bhumika 2024; https://doi.org/10.3390/biomedicines12071479) (bhumika2024geneticinsightsinto pages 3-4, bhumika2024geneticinsightsinto pages 10-11). - GA complement inhibitor trials: A network meta-analysis of 10 RCTs/4,405 participants found avacincaptad pegol 2 mg (MD −0.58 mm²), pegcetacoplan monthly (MD −0.38 mm²), and pegcetacoplan q2mo (MD −0.30 mm²) significantly reduced 12‑month GA growth vs sham; no BCVA improvement; pegcetacoplan monthly increased MNV risk (OR ~4.3) (Wang 2024; https://doi.org/10.3389/fphar.2024.1410172) (wilke2024complementregulationin pages 9-10).
Dysregulated pathways and affected cellular processes: Alternative complement pathway amplification (C3 convertase) and MAC deposition; PRR/TLR signaling→NLRP3→caspase‑1→IL‑1β/IL‑18; mitochondrial ROS generation, mitophagy defects; autophagy blockade with lysosomal overload (lipofuscin/A2E); cholesterol efflux defects (ABCA1/ABCG1) and oxidized lipid stress; VEGF‑A/VEGFR2 signaling for pathological angiogenesis (Wilke & Apte 2024) (wilke2024complementregulationin pages 9-10); (Hernández 2025) (hernandez2025roleofoxidative pages 8-10, hernandez2025roleofoxidative pages 6-8); (Basyal 2024) (basyal2024antioxidantsandmechanistic pages 2-4); (Ban 2024) (ban2024druseninamd pages 4-5); (Ong 2024) (ong2024agerelatedmaculardegeneration pages 5-7).
Key Molecular Players
Anatomical Locations (UBERON): Macula; Bruch’s membrane; sub‑RPE space; choriocapillaris (Wilke & Apte 2024) (wilke2024complementregulationin pages 9-10); (Basyal 2024) (basyal2024antioxidantsandmechanistic pages 2-4).
Biological Processes (GO annotation)
Complement activation (GO:0006956), regulation (GO:0030449), and terminal pathway/MAC assembly; innate immune signaling via PRRs/TLRs (GO:0002224) and inflammasome activation (GO:0002758); response to oxidative stress (GO:0006979), mitochondrial organization (GO:0007005), mitophagy (GO:0000422); lipid transport and cholesterol efflux (GO:0034381), lipid oxidation (GO:0034440); autophagy (GO:0006914), lysosome organization (GO:0007040); angiogenesis (GO:0001525), VEGF receptor signaling (GO:0048010) (Wilke & Apte 2024) (wilke2024complementregulationin pages 9-10); (Hernández 2025) (hernandez2025roleofoxidative pages 8-10); (Basyal 2024) (basyal2024antioxidantsandmechanistic pages 2-4); (Ban 2024) (ban2024druseninamd pages 4-5); (Ong 2024) (ong2024agerelatedmaculardegeneration pages 5-7).
Cellular Components
Key locales: RPE apical phagolysosomes and lysosomes (lipofuscin accumulation), mitochondria (ROS/mitophagy), Bruch’s membrane and sub‑RPE extracellular space (drusen, basal deposits), choriocapillaris endothelium (MAC deposition), extracellular matrix (vitronectin, collagens) (Wilke & Apte 2024) (wilke2024complementregulationin pages 9-10); (Basyal 2024) (basyal2024antioxidantsandmechanistic pages 2-4).
Disease Progression
Distinct stages: Early/intermediate AMD marked by drusen and pigmentary changes; advanced forms include GA (atrophic) and neovascular AMD (exudative CNV). Imaging biomarkers (OCT drusen morphology, subretinal drusenoid deposits, GA margins) align with sites of Bruch’s membrane change and atrophy expansion (Basyal 2024) (basyal2024antioxidantsandmechanistic pages 2-4); (Wilke & Apte 2024) (wilke2024complementregulationin pages 9-10).
Phenotypic Manifestations (HP terms)
Gene/protein annotations with ontology terms - CFH (HGNC:4883): complement regulation; GO:0006956 complement activation; evidence: complement dysregulation central; genetic variants confer risk (Wilke & Apte 2024; https://doi.org/10.1172/JCI178296) (wilke2024complementregulationin pages 9-10). - C3 (HGNC:1330): complement activation; therapeutic target; evidence: C3 inhibition slows GA growth in RCTs (Ban 2024; https://doi.org/10.3390/jcm13092608) (ban2024druseninamd pages 4-5). - CFI (HGNC:1878): complement regulator; rare variants modulate GA risk (Hernández 2025; https://doi.org/10.3390/ijms26083463) (hernandez2025roleofoxidative pages 8-10). - ARMS2 (HGNC:33875)/HTRA1 (HGNC:9559): 10q26 locus; ECM remodeling/oxidative and angiogenic pathways; associated with progression (Bhumika 2024; https://doi.org/10.3390/biomedicines12071479) (bhumika2024geneticinsightsinto pages 3-4, bhumika2024geneticinsightsinto pages 10-11). - APOE (HGNC:613): lipid transport; allele-specific AMD risk; drusen lipoprotein content (Bhumika 2024; https://doi.org/10.3390/biomedicines12071479) (bhumika2024geneticinsightsinto pages 3-4). - ABCA1 (HGNC:29), LIPC (HGNC:6597), CETP (HGNC:1869): cholesterol efflux/HDL metabolism; implicated in AMD lipid dysregulation/drusen (Ban 2024; https://doi.org/10.3390/jcm13092608) (ban2024druseninamd pages 4-5); (Bhumika 2024) (bhumika2024geneticinsightsinto pages 3-4). - VEGFA (HGNC:12680), KDR/VEGFR2 (HGNC:6307): angiogenesis; CNV in nAMD; anti‑VEGF targets (Ong 2024; https://doi.org/10.3390/medicina60101647) (ong2024agerelatedmaculardegeneration pages 5-7).
Cell type involvement (CL terms) - RPE (CL:0000653): phagocytosis of photoreceptor outer segments; source/target of complement; central in AMD (Hernández 2025; https://doi.org/10.3390/ijms26083463) (hernandez2025roleofoxidative pages 8-10). - Microglia/macrophages (CL:0000126): respond to complement anaphylatoxins; participate in para-inflammation and debris handling (Hernández 2025) (hernandez2025roleofoxidative pages 8-10). - Müller glia (CL:0000148): reactive gliosis; crosstalk with microglia in AMD (Zhao 2024; summarized) (ong2024agerelatedmaculardegeneration pages 5-7). - Choriocapillaris endothelial cells: MAC deposition and vascular loss adjacent to Bruch’s membrane (Wilke & Apte 2024) (wilke2024complementregulationin pages 9-10).
Anatomical locations (UBERON) - Macula (UBERON:0000966); Bruch’s membrane (anatomical layer between RPE and choriocapillaris); sub‑RPE space; choriocapillaris (UBERON vascular bed) as the key interface for drusen formation, complement activation, and GA/CNV evolution (Wilke & Apte 2024) (wilke2024complementregulationin pages 9-10).
Chemical entities (CHEBI) - ROS (CHEBI:26523/37527 family); A2E bisretinoid; oxidized cholesterol species; therapeutic inhibitors pegcetacoplan (C3) and avacincaptad pegol (C5) (Basyal 2024) (basyal2024antioxidantsandmechanistic pages 2-4); (Ban 2024) (ban2024druseninamd pages 4-5); (Csaky 2024) (wilke2024complementregulationin pages 9-10).
Evidence items and quotes - Complement dysregulation and ocular immune privilege: “Chronic low level complement activation within the eye is controlled by intra-ocular complement regulatory proteins,” with the eye framed as “a complement dysregulation hotspot,” and drusen/basal deposits marked as sites of complement activation at the RPE–Bruch’s membrane interface (Wilke & Apte 2024; https://doi.org/10.1172/JCI178296) (wilke2024complementregulationin pages 9-10). - Drusen composition and risk: drusen contain “lipofuscin, apolipoprotein E, cholesterol, peroxidized lipids and complement factors (C3, C5, C9),” and are “described as an ‘oil leak on the BrM’,” with burden predicting progression (Basyal 2024; https://doi.org/10.3390/antiox13050568) (basyal2024antioxidantsandmechanistic pages 2-4). - Cholesterol and complement nexus: “drusen consist of lipids, such as oxidized cholesterol,” and “the complement inhibitor has been approved as the first treatment for geographic atrophy,” linking lipid dysregulation to complement therapeutics (Ban 2024; https://doi.org/10.3390/jcm13092608) (ban2024druseninamd pages 4-5). - Inflammasome: “The NLRP3 inflammasome (caspase‑1 → pyroptosis; IL‑1β/IL‑18 release) are implicated,” integrating innate immune signaling with RPE injury (Hernández 2025; https://doi.org/10.3390/ijms26083463) (hernandez2025roleofoxidative pages 8-10). - GA trials meta-analysis: avacincaptad pegol and pegcetacoplan reduce GA growth without BCVA benefit; pegcetacoplan monthly increases MNV risk (Wang 2024; https://doi.org/10.3389/fphar.2024.1410172) (wilke2024complementregulationin pages 9-10).
Ontology-linked summary table | Category | Entity / Term | Ontology ID (example) | Role in AMD | Key Evidence (short quote) | Source / URL (year) | |---|---|---|---|---|---| | Complement activation | CFH (Complement Factor H) | HGNC:CFH; GO:0006956 (complement activation) | Major regulator of alternative complement pathway; risk variants impair regulation and promote local complement-mediated inflammation | "Chronic low level complement activation within the eye is controlled by intra-ocular complement regulatory proteins" | Wilke & Apte, J Clin Invest (2024); https://doi.org/10.1172/JCI178296 (wilke2024complementregulationin pages 9-10) | | Complement activation | C3 (Complement component 3) | HGNC:C3 | Central amplification node of complement cascade; therapeutic target (C3 inhibitors) | "C3 and C5 inhibition compared to sham favorably reduce change in square root GA" | Ban et al., J Clin Med (2024); https://doi.org/10.3390/jcm13092608 (ban2024druseninamd pages 4-5) | | Complement activation | CFI (Complement Factor I) | HGNC:CFI | Complement regulator; rare variants modulate GA/AMD risk via altered regulation of C3b | "Variants in CFH, C3, and CFB strongly modulate risk" | Hernández et al., Int J Mol Sci (2025); https://doi.org/10.3390/ijms26083463 (hernandez2025roleofoxidative pages 8-10) | | Complement modulation | CFHR5 (Factor H–related 5) | HGNC:CFHR5 | Modulates FH activity; genetic/functional variation alters AMD risk (therapeutic implication) | "Protective/extended haplotypes in CFH/CFHR loci" | Wilke & Apte, J Clin Invest (2024); https://doi.org/10.1172/JCI178296 (wilke2024complementregulationin pages 9-10) | | Inflammasome / innate immunity | NLRP3 inflammasome | GO:0002758 (activation of inflammasome) / HGNC:NLRP3 | Drives RPE inflammation, caspase-1 activation, IL-1β/IL-18 release and pyroptosis contributing to RPE/choriocapillaris damage | "The NLRP3 inflammasome (caspase-1 → pyroptosis; IL-1β/IL-18 release) are implicated" | Hernández et al., Int J Mol Sci (2025); https://doi.org/10.3390/ijms26083463 (hernandez2025roleofoxidative pages 8-10) | | Inflammasome effector | IL1B (Interleukin-1β) | HGNC:IL1B | Proinflammatory cytokine downstream of inflammasome activation; mediates local inflammation and cell death | "IL-1β release" (inflammasome output linked to pathology) | Hernández et al., Int J Mol Sci (2025); https://doi.org/10.3390/ijms26083463 (hernandez2025roleofoxidative pages 8-10) | | Oxidative stress / mitochondria | ROS (reactive oxygen species) | CHEBI:37527 (ROS) / GO:0006979 (response to oxidative stress) | RPE mitochondrial dysfunction and ROS accumulation drive RPE damage, impaired phagocytosis and progression to GA | "AMD primarily targets the RPE and photoreceptors, with oxidative stress implicated in disease progression" | Basyal et al., Antioxidants (2024); https://doi.org/10.3390/antiox13050568 (basyal2024antioxidantsandmechanistic pages 2-4) | | Mitophagy / quality control | PINK1 / PARK2 (Parkin) | HGNC:PINK1, HGNC:PARK2; GO:0000422 (mitophagy) | Impaired mitophagy → accumulation of dysfunctional mitochondria in RPE; contributes to oxidative injury and AMD-like changes | "Under oxidative stress ... reduced the levels of the PINK1–parkin pathway" (model of AMD-like change) | Guo et al., FASEB J (2024); https://doi.org/10.1096/fj.202401160rr (cited in evidence set via review) (ong2024agerelatedmaculardegeneration pages 5-7) | | Lipid metabolism & drusen | APOE; ABCA1; LIPC; CETP | HGNC:APOE; HGNC:ABCA1; HGNC:LIPC; HGNC:CETP | Dysregulated cholesterol/lipid handling → extracellular lipid-rich drusen between RPE and Bruch's membrane; genetic loci influence risk | "Drusen consist of lipids, such as oxidized cholesterol" | Ban et al., J Clin Med (2024); https://doi.org/10.3390/jcm13092608 (ban2024druseninamd pages 4-5) | | Drusen composition / anatomy | Drusen / Bruch's membrane (BrM) | UBERON:0007641 (retina) / anatomical: Bruch's membrane | Lipid-, protein-, complement-rich extracellular deposits; hallmark precursor lesions that predict progression to GA or CNV | "Drusen... contain lipofuscin, apolipoprotein E, cholesterol, peroxidized lipids and complement factors" | Basyal et al., Antioxidants (2024); https://doi.org/10.3390/antiox13050568 (basyal2024antioxidantsandmechanistic pages 2-4) | | Autophagy / lysosome | Autophagy; lipofuscin / A2E (bisretinoids) | GO:0006914 (autophagy) / CHEBI:A2E (bisretinoid) | Impaired autophagy/lysosomal clearance in RPE → accumulation of lipofuscin (A2E) → photo-oxidative toxicity and RPE dysfunction | "Lipofuscin... toxic bisretinoids (A2E) initiate... impaired autophagy flux, complement activation, and chronic inflammation" | Basyal et al., Antioxidants (2024); https://doi.org/10.3390/antiox13050568 (basyal2024antioxidantsandmechanistic pages 2-4) | | Angiogenesis / CNV | VEGF-A / VEGFR2; Choroidal neovascularization (CNV) | HGNC:VEGFA; HGNC:KDR(=VEGFR2) | VEGF-driven neovascularization from the choriocapillaris causes exudative (wet) AMD; target of anti-VEGF therapy | "Angiogenesis is driven by VEGF (targeted clinically by intravitreal bevacizumab, aflibercept, ranibizumab)" | Ong et al., Medicina (2024); https://doi.org/10.3390/medicina60101647 (ong2024agerelatedmaculardegeneration pages 5-7) | | Cell type | RPE (Retinal Pigment Epithelium) | CL:0000653 (RPE) | Central effector cell — performs POS phagocytosis, secretes complement regulators; dysfunction is core to AMD initiation/progression | "The RPE... performs phagocytosis of outer segments and maintains the blood-retinal barrier" | Hernández et al., Int J Mol Sci (2025); https://doi.org/10.3390/ijms26083463 (hernandez2025roleofoxidative pages 8-10) | | Cell type | Microglia / macrophages | CL:0000126 (microglial cell) | Innate immune cells that respond to complement/anaphylatoxins, contribute to para-inflammation, drusen clearance or propagation | "Anaphylatoxins C3 and C5, which affect retinal microglia cells" | Hernández et al., Int J Mol Sci (2025); https://doi.org/10.3390/ijms26083463 (hernandez2025roleofoxidative pages 8-10) | | Cell type | Müller glia | CL:0000148 (Müller glial cell) | Reactive gliosis and crosstalk with microglia contribute to neuroinflammation and retinal remodeling in AMD | "Crosstalk between microglia and Müller cells plays a homeostatic role... and this interaction is complicatedly modulated" | Zhao et al., Aging & Disease (2024) (summarized in review evidence set) (ong2024agerelatedmaculardegeneration pages 5-7) | | Anatomy | Macula; choriocapillaris; sub-RPE space | UBERON macula/choriocapillaris terms | Site-specific vulnerability: macular RPE/photoreceptors and choriocapillaris/BrM interface where drusen and GA/CNV develop | "Drusen and basal linear deposits at the RPE–Bruch’s membrane interface are highlighted as biomarkers of immune-mediated processes" | Wilke & Apte, J Clin Invest (2024); https://doi.org/10.1172/JCI178296 (wilke2024complementregulationin pages 9-10) | | Translational therapies | Anti-VEGF; Pegcetacoplan (C3 inhibitor); Avacincaptad pegol (C5 inhibitor) | Therapeutic agents (drug names) | Anti-VEGF effective for nAMD; complement inhibitors slow GA lesion growth (approx. ~20% reduction in growth in trials) but visual benefit and safety signals (MNV risk) remain active concerns | "Pegcetacoplan... received FDA approval in 2023"; "reduce GA lesion growth... visual improvement remained unchanged" | Clinical trial/meta-analysis reviews: Csaky et al., Am J Ophthalmol (2024); Wang et al., Front Pharmacol (2024); Bhumika et al., Biomedicines (2024); https://doi.org/10.1016/j.ajo.2024.02.021; https://doi.org/10.3389/fphar.2024.1410172; https://doi.org/10.3390/biomedicines12071479 (wilke2024complementregulationin pages 9-10, bhumika2024geneticinsightsinto pages 3-4, bhumika2024geneticinsightsinto pages 10-11) |
Table: Concise, evidence-linked summary table of key molecular/cellular mechanisms, genes, tissues, and translational therapies in AMD; each row includes ontology examples and a short quoted evidence snippet with source (2023–2025 reviews/meta-analyses).
Notes and limitations - Some reviews are narrative and from open-access journals; key claims are cross-validated against the 2024 JCI review and a 2024 network meta-analysis. Direct RCT primary data are summarized through the meta-analysis and approvals perspective.
References
(wilke2024complementregulationin pages 9-10): Georgia A. Wilke and Rajendra S. Apte. Complement regulation in the eye: implications for age-related macular degeneration. The Journal of Clinical Investigation, May 2024. URL: https://doi.org/10.1172/jci178296, doi:10.1172/jci178296. This article has 27 citations.
(basyal2024antioxidantsandmechanistic pages 2-4): Deepak Basyal, Sooyeun Lee, and Hye Jin Kim. Antioxidants and mechanistic insights for managing dry age-related macular degeneration. Antioxidants, 13:568, May 2024. URL: https://doi.org/10.3390/antiox13050568, doi:10.3390/antiox13050568. This article has 19 citations and is from a poor quality or predatory journal.
(ban2024druseninamd pages 4-5): Norimitsu Ban, Ari Shinojima, Kazuno Negishi, and Toshihide Kurihara. Drusen in amd from the perspective of cholesterol metabolism and hypoxic response. Journal of Clinical Medicine, 13:2608, Apr 2024. URL: https://doi.org/10.3390/jcm13092608, doi:10.3390/jcm13092608. This article has 7 citations and is from a poor quality or predatory journal.
(hernandez2025roleofoxidative pages 8-10): María Elena Ochoa Hernández, Lidianys María Lewis-Luján, María Guadalupe Burboa Zazueta, Teresa Del Castillo Castro, Enrique De La Re Vega, Juan Carlos Gálvez-Ruiz, Sergio Trujillo-López, Marco Antonio López Torres, and Simon Bernard Iloki-Assanga. Role of oxidative stress and inflammation in age related macular degeneration: insights into the retinal pigment epithelium (rpe). International Journal of Molecular Sciences, 26:3463, Apr 2025. URL: https://doi.org/10.3390/ijms26083463, doi:10.3390/ijms26083463. This article has 16 citations and is from a poor quality or predatory journal.
(hernandez2025roleofoxidative pages 6-8): María Elena Ochoa Hernández, Lidianys María Lewis-Luján, María Guadalupe Burboa Zazueta, Teresa Del Castillo Castro, Enrique De La Re Vega, Juan Carlos Gálvez-Ruiz, Sergio Trujillo-López, Marco Antonio López Torres, and Simon Bernard Iloki-Assanga. Role of oxidative stress and inflammation in age related macular degeneration: insights into the retinal pigment epithelium (rpe). International Journal of Molecular Sciences, 26:3463, Apr 2025. URL: https://doi.org/10.3390/ijms26083463, doi:10.3390/ijms26083463. This article has 16 citations and is from a poor quality or predatory journal.
(ong2024agerelatedmaculardegeneration pages 5-7): J. Ong, Jay Chhablani, Mahendra Singh, Riyakshi Negi, Ramachandran Vinayagam, Sang Gu Kang, and Prashant Shukla. Age-related macular degeneration (amd): pathophysiology, drug targeting approaches, and recent developments in nanotherapeutics. Medicina, 60:1647, Oct 2024. URL: https://doi.org/10.3390/medicina60101647, doi:10.3390/medicina60101647. This article has 17 citations and is from a poor quality or predatory journal.
(bhumika2024geneticinsightsinto pages 3-4): Bhumika, Nalini S. Bora, and Puran S. Bora. Genetic insights into age-related macular degeneration. Biomedicines, 12:1479, Jul 2024. URL: https://doi.org/10.3390/biomedicines12071479, doi:10.3390/biomedicines12071479. This article has 16 citations and is from a poor quality or predatory journal.
(bhumika2024geneticinsightsinto pages 10-11): Bhumika, Nalini S. Bora, and Puran S. Bora. Genetic insights into age-related macular degeneration. Biomedicines, 12:1479, Jul 2024. URL: https://doi.org/10.3390/biomedicines12071479, doi:10.3390/biomedicines12071479. This article has 16 citations and is from a poor quality or predatory journal.