Age-related macular degeneration (AMD) is an age-related neurodegenerative eye disease characterized by degeneration and progressive death of retinal pigment epithelium (RPE) and photoreceptor cells. In recent years, as a new treatment for AMD, stem cell therapy has attracted wide attention in the field of AMD, and has become a current research hotspot. Although stem cell therapy carries risks such as increased incidence of cancer and immune rejection, it significantly promotes damaged photoreceptor cells and retinal cells by differentiating into RPE cells and other retinal cell types, as well as secreting neurotrophic factors and extracellular vesicles. In particular, the development of embryonic stem cell-derived RPE cells, its cryopreservation technology and the advancement of plasmid, adeno-associated virus, Sendai virus and other delivery technologies have laid a solid foundation for stem cell therapy of AMD. As a new method to prevent retinal damage and photoreceptor degeneration, stem cell neuroprotective therapy has shown great potential, and with the continuous maturity and improvement of these technologies, stem cell therapy is expected to provide new ideas for the prevention and treatment of AMD in the future.
Vascular endothelial growth factor (VEGF) is a multifunctional factor that promotes blood vessel formation and increases vascular permeability. Its abnormal elevation plays a key role in common retinal diseases such as wet age-related macular degeneration and diabetic macular edema. Anti-VEGF therapy can inhibit angiogenesis, reduce vascular leakage and edema, thereby delaying disease progression and stabilizing or improving vision. Currently, the clinical application of anti-VEGF drugs has achieved satisfactory therapeutic effects, but there are also issues such as high injection frequency, heavy economy burden, potential systemic side effects, and non-responsiveness. To address these issues, current research and development mainly aim on biosimilars, multi-target drugs, drug delivery systems, oral anti-VEGF drugs, and gene therapy. Some drugs have shown great potential and are expected to turn over a new leaf for anti-VEGF treatment in ophthalmology.
Lipid globules in retina and choroid are new definitions based on pathology and high-resolution optical coherence tomography (OCT). OCT examination shows that the lipid globules are low reflective circular cavities in the choroid and retina, without strong reflective boundaries around them, followed by a characteristic superreflective tail. It occurs in healthy human eyes and in age-related macular degeneration characterized by retinal pigment epithelium (RPE) atrophy. Its characteristic superreflective tail is the key to distinguishing it from other diseases. At present, the understanding of lipid globules is still in the initial stage. Although lipid globules can be observed in healthy human eyes, a certain prevalence rate indicates that they are associated with choroidal hypoperfusion and RPE atrophy. In the future, larger randomized controlled trials and longer follow-up time are needed to explore its pathogenesis, pathological characteristics and treatment prognosis.
Age-related macular degeneration (AMD) involves dysregulation of the innate immune response of complement and mononuclear phagocytes and abnormalities of local microglia. When microglia transition from a resting state to an active state, their metabolic pathway also changes, known as "metabolic reprogramming", and their glucose metabolic reprogramming is a key factor in the pathogenesis of AMD, involving multiple signaling pathways. Including phosphatidylinositol 3-kinase-serine threonine kinase-rapamycin target, adenylate activated protein kinase and hypoxia-inducing factor 1 pathway. These metabolic changes regulate the inflammatory response, energy supply, and neuroprotective functions of microglia. Therapeutic strategies to regulate the reprogramming of glucose metabolism in microglia have achieved initial results. Future studies should further explore the mechanisms of microglia metabolic regulation to develop new targeted drugs and intervene in the treatment of AMD through anti-cellular aging pathways.
Age-related macular degeneration (AMD) is one of the leading causes of vision impairment and blindness in the elderly worldwide, with its prevalence increasing significantly with age. The pathogenesis of AMD is multifactorial, involving genetic predisposition, environmental risk factors, chronic inflammation, and mitochondrial dysfunction. In recent years, mitophagy has emerged as a critical mechanism for maintaining mitochondrial quality control, energy homeostasis, and cellular integrity in retinal pigment epithelium (RPE) and photoreceptor cells. Dysregulated mitophagy leads to the accumulation of damaged mitochondria, excessive reactive oxygen species, and metabolic imbalance, thereby triggering RPE dysfunction, inflammatory amplification, and choroidal neovascularization, which drive AMD progression. Both classical pathways (e.g., PINK1/Parkin) and non-classical pathways (e.g., BNIP3, FUNDC1) have been implicated in AMD pathophysiology. Molecules such as Parkin and p62, as well as multimodal imaging features, hold promise as early biomarkers for disease monitoring. Preclinical studies have shown that small-molecule activators (e.g., Urolithin A, Spermidine) and mitochondria-targeted antioxidants (e.g., MitoQ, SkQ1) can restore mitophagy and alleviate RPE damage. However, current evidence remains limited, as large-scale, long-term clinical trials are lacking. Challenges in drug delivery efficiency, safety, patient stratification, and clinical monitoring tools still hinder translation into practice. Future research should focus on biomarker-driven precision interventions, multicenter randomized controlled trials, and individualized therapeutic strategies. Overall, mitophagy research is transitioning from mechanistic exploration to clinical translation, with promising potential to enable early diagnosis, disease stratification, and precision management of AMD.
Objective
To observe the characteristics of indocyanine green angiography in exudative age-related macular degeneration.
Methods
Thirty one cases(36 eyes)were diagnosed as exudative age-related macular degeneration by ocular examination,fundus color photography,fundus fluorescein angiography(FFA)and indocyanine green angiography(ICGA).Their ages ranged from 50 to 82 years.The visual acuities were FC/30cm before eye to 0.7.We analyzed and compared the characteristics of ICGA and FFA in these patients.
Results
Of 26 eyes with occult choroidal neovascularization(CNV)by FFA,15(57.7%)had classic CNV.Of 4 eyes with serous retinal pigment epithelial detachment(PED)without CNV by FFA,l had serous PED with classic CNV.The hyperfluorescence of the scar stain was defected by ICGA.
Conclusion
ICGA adds clinically useful information and is important in laser treatment of patients with occult CNV in AMD.
(Chin J Ocul Fundus Dis,1998,14:76-80)
Age-related macular degeneration (AMD) represents a significant cause of visual impairment and blindness in individuals over 65 years old. In recent years, gene therapy has emerged as a research hotspot for wet AMD, with adeno-associated virus (AAV) vectors being widely utilized due to their non-pathogenic nature, low immunogenicity, broad tissue tropism, and capacity for sustained transgene expression. Several related studies have progressed to clinical trial stages. Although challenges persist, including immunogenicity concerns, limited vector capacity, and potential long-term adverse effects, the continuous advancement of research strategies and technologies holds promise. Future developments may employ AAV delivery systems to achieve gene supplementation, gene editing, or gene silencing of angiogenesis-related signaling molecules, thereby providing novel therapeutic approaches for wet AMD.
Age-related macular degeneration (AMD) is one of the leading causes of irreversible vision loss. There are two primary forms of AMD: exudative age-related macular degeneration (WAMD) and atrophic AMD (DAMD). While numerous medications are currently available for the treatment of WAMD, yielding significant therapeutic outcomes, effective treatments for DAMD remain scarce. Various animal studies and clinical trials on DAMD treatment have been conducted, focusing primarily on antioxidants, complement pathway inhibitors, mitochondrial protectors, visual cycle inhibitors, neuroprotectants, amphiphilic polymer-based drug delivery systems, cell therapy, photobiomodulation therapy, gene therapy, surgical interventions, and traditional Chinese medicine. Among these, antioxidant supplementation with vitamins and complement pathway inhibitor APL-2 and ACP have received Food and Drug Administration approval for the treatment of DAMD. With the continuous development of the medical field, the future will explore the treatment methods with little trauma, good efficacy and good patient compliance, and successfully achieve clinical transformation.
With the tremendous progress in fundus imaging and histopathology over the past decade, the understanding of age-related macular degeneration (AMD) has taken a qualitative leap. AMD is defined as a progressive neurodegenerative disease of photoreceptors and retinal pigment epithelium (RPE) characterized by extracellular deposits under RPE and the retina, including drusen, basal laminar and linear deposits, and subretinal drusenoid deposits, that can evolve to atrophy of the retina, RPE and choroid and neovascularization in the choroid and/or retina. It is the leading cause of blindness and visual impairment in older populations, despite recent advances in treatments. AMD is a multifactorial disease with genetic and environmental factors including advanced age, smoking, high-fat diet, and cardiovascular disorder to enhance the disease susceptibility. The physiopathologic mechanism includes inflammatory processes (complement pathway dysregulation, inflammasome activation), intrinsic (e.g., photo-oxidation) and extrinsic oxidative insult to the retina, age-related metabolic impairment (mitochondrial, autophagic and endoplasmic reticulum stress). Autophagy dysfunction and local inflammation in aged RPE specially result in the extracellular deposits, cell death and AMD. Further investigation of the pathogenesis of AMD will provide with new therapeutic targets and strategy for prevention and treatment of the disease in the early stages.
The severe visual impairment caused by neovascular age-related macular degeneration (nAMD) is associated with macular neovascularization (MNV) invasion and subretinal fibrosis (SF). Excessive SF can lead to subretinal scarring, irreversible damage to photoreceptors, retinal pigment epithelium, and choroid tissue, resulting in permanent visual impairment in nAMD patients. The pathogenesis of SF is complex, involving many pathological processes such as tissue repair after injury, inflammation, and related signaling pathways and cytokine complex. Current experimental treatments for SF only target inhibition of a single cytokine. Timely and effective inhibition of the formation and progression of MNV and early identification of risk factors for SF are crucial to improving the prognosis of nAMD patients.
