Age-related macular degeneration: Epidemiology, genetics, pathophysiology, diagnosis, and targeted therapy

Comparative evaluation of four Lycium barbarum cultivars on NaIO3-induced retinal degeneration mice via multivariate statistical analysis

ETHNOPHARMACOLOGICAL RELEVANCE

The fruit of Lycium barbarum L. (goji berry) is a traditional Chinese medicine and is often used to improve vision. While various goji cultivars may differentially treat retinal degeneration, however their comparative effectiveness remains unclear.

AIM OF THE STUDY

To evaluate the protective effects of four goji cultivars on NaIO3-induced retinal degeneration mouse model and identify the most therapeutically potent cultivar.

MATERIALS AND METHODS

The principal compounds in the extracts of four goji cultivars were characterized by UPLC-Q-TOF/MS. A retinal degeneration mouse model was established via NaIO3 injection. Dark-light transition and TUNEL assays were used to assess visual function and retinal apoptosis. The levels of antioxidative, inflammatory, and angiogenic markers in serums and eyeballs were measured. Hierarchical cluster analysis, principal component analysis and partial least squares-discriminant analysis were used to objectively compare the treatment responses.

RESULTS

Sixteen compounds were identified in goji berry extracts. All goji berry extracts could reverse NaIO3-induced visual impairment, retinal damage and apoptosis. The samples from the cultivar of Ningqi No.1 significantly modulated oxidative stress, inflammation, and vascular endothelial growth factor levels, which are more effectively than the other cultivars based on integrated multivariate profiling.

CONCLUSION

Ningqi No.1 demonstrated a stronger protective effect on mouse retina than other goji cultivars, and is a potential variety for further research on the treatment of retinal degeneration.

Obesity, body fat distribution and eye diseases

BACKGROUND

The prevalence of obesity, a chronic disease, is increasing, and obesity is now considered a global epidemic. Eye diseases are also increasing worldwide and have serious repercussions on quality of life as well as increasingly high costs for the community. The relationships between obesity and ocular pathologies are not yet well clarified and are not pathologically homogeneous: they seem to be somehow linked to excess body fat, especially to the distribution of adipose tissue and its ectopic deposits.

PURPOSE

Our objective was to examine the associations between obesity and anthropometric indices, including body mass index (BMI), waist circumference (WC), and the waist/hip ratio (WHR), and the risk of most widespread eye diseases, with particular attention given to the most significant metabolic mechanisms.

METHODS

This article provides a narrative overview of the effect of obesity and anthropometric measurements of body fat on prevalent eye diseases. We used the MEDLINE/PubMed, CINAHL, EMBASE, and Cochrane Library databases from 1984 to 2024. In addition, we hand-searched references from the retrieved articles and explored a number of related websites. A total of 153 publications were considered.

RESULTS

There is significant evidence that obesity is associated with several eye diseases. Waist circumference (WC) and the waist/hip ratio (WHR) have been observed to have stronger positive associations with eye diseases than BMI.

CONCLUSIONS

Obesity must be considered a significant risk factor for eye diseases; hence, a multidisciplinary and multidimensional approach to treating obesity, which also affects ocular health, is important. In the prevention and treatment of eye diseases related to obesity, lifestyle factors, especially diet and physical activity, as well as weight changes, both weight loss and weight gain, should not be overlooked.

LEVEL OF EVIDENCE

Level V narrative review.

Progress in the Study of the Role and Mechanism of HTRA1 in Diseases Related to Vascular Abnormalities

High temperature requirement A1 (HTRA1) is a member of the serine protease family, comprising four structural domains: IGFBP domain, Kazal domain, protease domain and PDZ domain. HTRA1 encodes a serine protease, a secreted protein that is widely expressed in the vasculature. HTRA1 regulates a wide range of physiological processes through its proteolytic activity, and is also involved in a variety of vascular abnormalities-related diseases. This article reviews the role of HTRA1 in the development of vascular abnormalities-related hereditary cerebral small vessel disease (CSVD), age-related macular degeneration (AMD), tumors and other diseases. Through relevant research advances to understand the role of HTRA1 in regulating signaling pathways or refolding, translocation, degradation of extracellular matrix (ECM) proteins, thus directly or indirectly regulating angiogenesis, vascular remodeling, and playing an important role in vascular homeostasis, further understanding the mechanism of HTRA1's role in vascular abnormality-related diseases is important for HTRA1 to be used as a therapeutic target in related diseases.

Changes in ocular blood flow in patients with neovascular age-related macular degeneration after intravitreal injection of ranibizumab biosimilar and brolucizumab

PURPOSE

To assess ocular blood flow (OBF) changes in patients with neovascular age-related macular degeneration (nAMD) treated with intravitreal injections of ranibizumab biosimilar (IVRbs) or brolucizumab (IVBr).

METHODS

This retrospective longitudinal study included 43 eyes of 43 patients (74.5 ± 9.8 years old, male to female ratio 31:12) with nAMD treated with IVBr (29 eyes) or IVRbs (14 eyes). OBF in the optic nerve head (ONH) and choroid (Ch) was measured with laser speckle flowgraphy (Softcare Co., Ltd., Fukutsu, Japan) before and one month after treatment. Changes in mean blur rate (MBR) before and after each treatment were tested using Wilcoxon's signed-rank tests and mixed-effect models for repeated measures.

RESULTS

In the IVBr group, MBR was significantly reduced in both the ONH and Ch (p < 0.01). In contrast, the IVRbs group showed no significant change in MBR in either the ONH or Ch (p = 0.56, p = 1). The linear mixed effect model showed a significant interaction between time and anti-VEGF drugs for MBR in both the ONH and Ch (ONH: p = 0.04; Ch: p = 0.002). A post hoc pairwise comparison of estimated marginal means showed that MBR decreased significantly only after IVBr (p < 0.001).

CONCLUSION

Our findings suggest that the short-term impact on OBF varies depending on the drug used for nAMD.

The Role of Glutathione in Age-Related Macular Degeneration (AMD)

Age-related macular degeneration (AMD) is a chronic disease that usually develops in older people. Pathogenetic changes in this disease include anatomical and functional complexes. Harmful factors damage the retina and macula. These changes may lead to partial or total loss of vision. The disease can occur in two clinical forms: dry (the progression is slow and gentle) and exudative (wet-progression is acute and severe), which usually starts in the dry form; however, the coexistence of both forms is possible. The etiology of AMD is not fully understood, and the precise mechanisms of the development of this illness are still unknown. Extensive genetic studies have shown that AMD is a multi-factorial disease and that genetic determinants, along with external and internal environmental and metabolic-functional factors, are important risk factors. This article reviews the role of glutathione (GSH) enzymes engaged in maintaining the reduced form and polymorphism in glutathione S-transferase theta-1 (GSTT1) and glutathione S-transferase mu-1 (GSTM1) in the development of AMD. We only chose papers that confirmed the influence of the parameters on the development of AMD. Because GSH is the most important antioxidant in the eye, it is important to know the influence of the enzymes and genetic background to ensure an optimal level of glutathione concentration. Numerous studies have been conducted on how the glutathione system works till today. This paper presents the current state of knowledge about the changes in GSH, GST, GR, and GPx in AMD. GST studies clearly show increased activity in ill people, but for GPx, the results relating to activity are not so clear. Depending on the research, the results also suggest higher and lower GPx activity in patients with AMD. The analysis of polymorphisms in GST genes confirmed that mutations lead to weaker antioxidant barriers and may contribute to the development of AMD; unfortunately, a meta-analysis and some research did not confirm that connection. Unspecific results of many of the parameters that make up the glutathione system show many unknowns. It is so important to conduct further research to understand the exact mechanism of defense functions of glutathione against oxidative stress in the human eye.

Association of Genetic Risk for Age-Related Macular Degeneration with Morphological Features of the Retinal Microvascular Network

BACKGROUND

Age-related macular degeneration (AMD) is a multifactorial disease encompassing a complex interaction between aging, environmental risk factors, and genetic susceptibility. The study aimed to determine whether there is a relationship between the polygenic risk score (PRS) in patients with AMD and the characteristics of the retinal vascular network visualized by optical coherence tomography angiography (OCTA).

METHODS

235 patients with AMD and 97 healthy controls were included. We used data from a previous AMD PRS study with the same group. The vascular features from different retina layers were compared between the control group and the patients with AMD. The association between features and PRS was then analyzed using univariate and multivariate approaches.

RESULTS

Significant differences between the control group and AMD patients were found in the vessel diameter distribution (variance: p = 0.0193, skewness: p = 0.0457) and fractal dimension distribution (mean: p = 0.0024, variance: p = 0.0123). Both univariate and multivariate analyses showed no direct and significant association between the characteristics of the vascular network and AMD PRS.

CONCLUSIONS

The vascular features of the retina do not constitute a biomarker of the risk of AMD. We have not identified a genotype-phenotype relationship, and the expression of AMD-related genes is perhaps not associated with the characteristics of the retinal vascular network.

Microbial Dynamics in Ophthalmic Health: Exploring the Interplay between Human Microbiota and Glaucoma Pathogenesis

The human microbiome has a crucial role in the homeostasis and health of the host. These microorganisms along with their genes are involved in various processes, among these are neurological signaling, the maturation of the immune system, and the inhibition of opportunistic pathogens. In this sense, it has been shown that a healthy ocular microbiota acts as a barrier against the entry of pathogens, contributing to the prevention of infections. In recent years, a relationship has been suggested between microbiota dysbiosis and the development of neurodegenerative diseases. In patients with glaucoma, it has been observed that the microbiota of the ocular surface, intraocular cavity, oral cavity, stomach, and gut differ from those observed in healthy patients, which may suggest a role in pathology development, although the evidence remains limited. The mechanisms involved in the relationship of the human microbiome and this neurodegenerative disease remain largely unknown. For this reason, the present review aims to show a broad overview of the influence of the structure and composition of the human oral and gut microbiota and relate its dysbiosis to neurodegenerative diseases, especially glaucoma.

The Hippo signalling pathway and its impact on eye diseases

The Hippo signalling pathway, an evolutionarily conserved kinase cascade, has been shown to be crucial for cell fate determination, homeostasis and tissue regeneration. Recent experimental and clinical studies have demonstrated that the Hippo signalling pathway is involved in the pathophysiology of ocular diseases. This article provides the first systematic review of studies on the regulatory and functional roles of mammalian Hippo signalling systems in eye diseases. More comprehensive studies on this pathway are required for a better understanding of the pathophysiology of eye diseases and the development of effective therapies.

New Perspectives in Stem Cell Transplantation and Associated Therapies to Treat Retinal Diseases: From Gene Editing to 3D Bioprinting

Inherited and non-inherited retinopathies can affect distinct cell types, leading to progressive cell death and visual loss. In the last years, new approaches have indicated exciting opportunities to treat retinopathies. Cell therapy in retinitis pigmentosa, age-related macular disease, and glaucoma have yielded encouraging results in rodents and humans. The first two diseases mainly impact the photoreceptors and the retinal pigmented epithelium, while glaucoma primarily affects the ganglion cell layer. Induced pluripotent stem cells and multipotent stem cells can be differentiated in vitro to obtain specific cell types for use in transplant as well as to assess the impact of candidate molecules aimed at treating retinal degeneration. Moreover, stem cell therapy is presented in combination with newly developed methods, such as gene editing, Müller cells dedifferentiation, sheet & drug delivery, virus-like particles, optogenetics, and 3D bioprinting. This review describes the recent advances in this field, by presenting an updated panel based on cell transplants and related therapies to treat retinopathies.

Kaempferol: Paving the path for advanced treatments in aging-related diseases

Aging-related diseases (ARDs) are a major global health concern, and the development of effective therapies is urgently needed. Kaempferol, a flavonoid found in several plants, has emerged as a promising candidate for ameliorating ARDs. This comprehensive review examines Kaempferol's chemical properties, safety profile, and pharmacokinetics, and highlights its potential therapeutic utility against ARDs. Kaempferol's therapeutic potential is underpinned by its distinctive chemical structure, which confers antioxidative and anti-inflammatory properties. Kaempferol counteracts reactive oxygen species (ROS) and modulates crucial cellular pathways, thereby combating oxidative stress and inflammation, hallmarks of ARDs. Kaempferol's low toxicity and wide safety margins, as demonstrated by preclinical and clinical studies, further substantiate its therapeutic potential. Compelling evidence supports Kaempferol's substantial potential in addressing ARDs through several mechanisms, notably anti-inflammatory, antioxidant, and anti-apoptotic actions. Kaempferol exhibits a versatile neuroprotective effect by modulating various proinflammatory signaling pathways, including NF-kB, p38MAPK, AKT, and the β-catenin cascade. Additionally, it hinders the formation and aggregation of beta-amyloid protein and regulates brain-derived neurotrophic factors. In terms of its anticancer potential, kaempferol acts through diverse pathways, inducing apoptosis, arresting the cell cycle at the G2/M phase, suppressing epithelial-mesenchymal transition (EMT)-related markers, and affecting the phosphoinositide 3-kinase/protein kinase B signaling pathways. Subsequent studies should focus on refining dosage regimens, exploring innovative delivery systems, and conducting comprehensive clinical trials to translate these findings into effective therapeutic applications.

Estrogen related receptor alpha: Potential modulator of age-related macular degeneration

To develop effective therapies for complex blinding diseases such as age-related macular degeneration (AMD), identification of mechanisms involved in its initiation and progression is needed. The estrogen-related receptor alpha (ESRRA) is an orphan nuclear receptor that regulates several AMD-associated pathogenic pathways. However, it has not been investigated in detail in the ocular posterior pole during aging or in AMD. This review delves into the literature highlighting the significance of ESRRA as a molecular target that may be important in the pathobiology of AMD, and discusses data available supporting the targeting of this receptor signaling pathway as a therapeutic option for AMD.

Ferroptosis as a potential therapeutic target for age-related macular degeneration

Cell death plays a crucial part in the process of age-related macular degeneration (AMD), but its mechanisms remain elusive. Accumulating evidence suggests that ferroptosis, a novel form of regulatory cell death characterized by iron-dependent accumulation of lipid hydroperoxides, has a crucial role in the pathogenesis of AMD. Numerous studies have suggested that ferroptosis participates in the degradation of retinal cells and accelerates the progression of AMD. Furthermore, inhibitors of ferroptosis exhibit notable protective effects in AMD, underscoring the significance of ferroptosis as a pivotal mechanism in the death of retinal cells during the process of AMD. This review aims to summarize the molecular mechanisms of ferroptosis in AMD, enumerate potential inhibitors and discuss the challenges and future opportunities associated with targeting ferroptosis as a therapeutic strategy, providing important information references and insights for the prevention and treatment of AMD.

The impact of substrate stiffness on morphological, transcriptional and functional aspects in RPE

Alterations in the structure and composition of Bruch's membrane (BrM) and loss of retinal pigment epithelial (RPE) cells are associated with various ocular diseases, notably age-related macular degeneration (AMD) as well as several inherited retinal diseases (IRDs). We explored the influence of stiffness as a major BrM characteristic on the RPE transcriptome and morphology. ARPE-19 cells were plated on soft ( E = 30 kPa ) or stiff ( E = 80 kPa ) polyacrylamide gels (PA gels) or standard tissue culture plastic (TCP). Next-generation sequencing (NGS) data on differentially expressed small RNAs (sRNAs) and messenger RNAs (mRNAs) were validated by qPCR, immunofluorescence or western blotting. The microRNA (miRNA) fraction of sRNAs grew with substrate stiffness and distinct miRNAs such as miR-204 or miR-222 were differentially expressed. mRNA targets of differentially expressed miRNAs were stably expressed, suggesting a homeostatic effect of miRNAs. mRNA transcription patterns were substrate stiffness-dependent, including components of Wnt/beta-catenin signaling, Microphthalmia-Associated Transcription Factor (MITF) and Dicer. These findings highlight the relevance of mechanical properties of the extracellular matrix (ECM) in cell culture experiments, especially those focusing on ECM-related diseases, such as AMD.

Effects and potential mechanisms of exercise and physical activity on eye health and ocular diseases

In the field of eye health, the profound impact of exercise and physical activity on various ocular diseases has become a focal point of attention. This review summarizes and elucidates the positive effects of exercise and physical activities on common ocular diseases, including dry eye disease (DED), cataracts, myopia, glaucoma, diabetic retinopathy (DR), and age-related macular degeneration (AMD). It also catalogues and offers exercise recommendations based on the varying impacts that different types and intensities of physical activities may have on specific eye conditions. Beyond correlations, this review also compiles potential mechanisms through which exercise and physical activity beneficially affect eye health. From mitigating ocular oxidative stress and inflammatory responses, reducing intraocular pressure, enhancing mitochondrial function, to promoting ocular blood circulation and the release of protective factors, the complex biological effects triggered by exercise and physical activities reveal their substantial potential in preventing and even assisting in the treatment of ocular diseases. This review aims not only to foster awareness and appreciation for how exercise and physical activity can improve eye health but also to serve as a catalyst for further exploration into the specific mechanisms and key targets through which exercise impacts ocular health. Such inquiries are crucial for advancing innovative strategies for the treatment of eye diseases, thereby holding significant implications for the development of new therapeutic approaches.

Enhancing Readability and Detection of Age-Related Macular Degeneration Using Optical Coherence Tomography Imaging: An AI Approach

Artificial intelligence has been used effectively in medical diagnosis. The objective of this project is to examine the application of a collective AI model using weighted fusion of predicted probabilities from different AI architectures to diagnose various retinal conditions based on optical coherence tomography (OCT). A publicly available Noor dataset, comprising 16,822, images from 554 retinal OCT scans of 441 patients, was used to predict a diverse spectrum of age-related macular degeneration (AMD) stages: normal, drusen, or choroidal neovascularization. These predictions were compared with predictions from ResNet, EfficientNet, and Attention models, respectively, using precision, recall, F1 score, and confusion matric and receiver operating characteristics curves. Our collective model demonstrated superior accuracy in classifying AMD compared to individual ResNet, EfficientNet, and Attention models, showcasing the effectiveness of using trainable weights in the ensemble fusion process, where these weights dynamically adapt during training rather than being fixed values. Specifically, our ensemble model achieved an accuracy of 91.88%, precision of 92.54%, recall of 92.01%, and F1 score of 92.03%, outperforming individual models. Our model also highlights the refinement process undertaken through a thorough examination of initially misclassified cases, leading to significant improvements in the model's accuracy rate to 97%. This study also underscores the potential of AI as a valuable tool in ophthalmology. The proposed ensemble model, combining different mechanisms highlights the benefits of model fusion for complex medical image analysis.

The hypothetical molecular mechanism of the ethnic variations in the manifestation of age-related macular degeneration; focuses on the functions of the most significant susceptibility genes

Age-related macular degeneration (AMD) is the leading sight-threatening disease in developed countries. On the other hand, recent studies indicated an ethnic variation in the phenotype of AMD. For example, several reports demonstrated that the incidence of drusen in AMD patients is less in Asians compared to Caucasians though the reason has not been clarified yet. In the last decades, several genome association studies have disclosed many susceptible genes of AMD and revealed that the association strength of some genes was different among races and AMD phenotypes. In this review article, the essential findings of the clinical studies and genome association studies for the most significant genes CFH and ARMS2/HTRA1 in AMD of different races are summarized, and theoretical hypotheses about the molecular mechanisms underlying the ethnic variation in the AMD manifestation mainly focused on those genes between Caucasians and Asians are discussed.

A systematic review of economic evaluation of artificial intelligence-based screening for eye diseases: From possibility to reality

Artificial Intelligence (AI) has become a focus of research in the rapidly evolving field of ophthalmology. Nevertheless, there is a lack of systematic studies on the health economics of AI in this field. We examine studies from the PubMed, Google Scholar, and Web of Science databases that employed quantitative analysis, retrieved up to July 2023. Most of the studies indicate that AI leads to cost savings and improved efficiency in ophthalmology. On the other hand, some studies suggest that using AI in healthcare may raise costs for patients, especially when taking into account factors such as labor costs, infrastructure, and patient adherence. Future research should cover a wider range of ophthalmic diseases beyond common eye conditions. Moreover, conducting extensive health economic research, designed to collect data relevant to its own context, is imperative.

Next generation therapeutics for retinal neurodegenerative diseases

Neurodegenerative diseases affecting the visual system encompass glaucoma, macular degeneration, retinopathies, and inherited genetic disorders such as retinitis pigmentosa. These ocular pathologies pose a serious burden of visual impairment and blindness worldwide. Current treatment modalities include small molecule drugs, biologics, or gene therapies, most of which are administered topically as eye drops or as injectables. However, the topical route of administration faces challenges in effectively reaching the posterior segment and achieving desired concentrations at the target site, while injections and implants risk severe complications, such as retinal detachment and endophthalmitis. This necessitates the development of innovative therapeutic strategies that can prolong drug release, deliver effective concentrations to the back of the eye with minimal systemic exposure, and improve patient compliance and safety. In this review, we introduce retinal degenerative diseases, followed by a discussion of the existing clinical standard of care. We then delve into detail about drug and gene delivery systems currently in preclinical and clinical development, including formulation and delivery advantages/drawbacks, with a special emphasis on potential for clinical translation.

Association between age-related macular degeneration and risk of incident cancer

BACKGROUND/AIMS

Age-related macular degeneration (AMD) and cancer may share similar risk factors, indicating possible common pathogenic pathways. We aimed to describe the site-specific cancer risk based on the relationship of AMD with visual disability (VD) status.

METHODS

This was a population-based cohort study using data from the Korean National Health Insurance Service database (2009-2019) including patients who participated in a national health screening programme in 2009. The subjects were categorised based on the presence of AMD and VD. The occurrence of cancer was identified using principal diagnosis according to the International Classification of Disease, 10th revision codes in claims data. The Cox regression hazard model was used to compare HRs of site-specific cancer.

RESULTS

Among 4 088 814 participants, 51 596 had AMD of which 3683 subjects had VD. The mean follow-up period was 9.6 years. The overall cancer risk was generally null, but the risk of hypervascular cancer such as thyroid cancer (adjusted HR (aHR) 1.10, 95% CI 1.00 to 1.20) and renal cancer (aHR 1.16, 95% CI 1.00 to 1.33) was higher and the risk of stomach cancer (aHR 0.89, 95% CI 0.84 to 0.94) was lower in the AMD group than in the non-AMD group.

CONCLUSION

This study demonstrated a possible association between AMD and several cancers. Increased renal and thyroid cancer risk among patients with AMD could indicate that AMD is associated with hypervascular cancer. Further studies in which additional databases are used and the underlying detailed mechanisms evaluated are needed to validate our results.

Retinal structure and vessel density changes in cerebral small vessel disease

Background

Cerebral small vessel disease (CSVD) attaches people's attention in recent years. In this study, we aim to explore retinal structure and vessel density changes in CSVD patients.

Methods

We collected information on retinal metrics assessed by optical coherence tomography (OCT) and OCT angiography and CSVD characters. Logistic and liner regression was used to analyze the relationship between retinal metrics and CSVD.

Results

Vessel density of superficial retinal capillary plexus (SRCP), foveal density- 300 length (FD-300), radial peripapillary capillary (RPC) and thickness of retina were significantly lower in CSVD patients, the difference only existed in the thickness of retina after adjusted relevant risk factors (OR (95% CI): 0.954 (0.912, 0.997), p = 0.037). SRCP vessel density showed a significant downward trend with the increase of CSVD scores (β: -0.087, 95%CI: -0.166, -0.008, p = 0.031). SRCP and FD-300 were significantly lower in patients with lacunar infarctions and white matter hypertensions separately [OR (95% CI): 0.857 (0.736, 0.998), p = 0.047 and OR (95% CI): 0.636 (0.434, 0.932), p = 0.020, separately].

Conclusion

SRCP, FD-300 and thickness of retina were associated with the occurrence and severity of total CSVD scores and its different radiological manifestations. Exploring CSVD by observing alterations in retinal metrics has become an optional research direction in future.

Using the Amsler Grid Test for Age-Related Macular Degeneration Screening

Objectives

To evaluate the use of the Amsler grid test (AGT) in screening for age-related macular degeneration (AMD), one of the most common causes of blindness, in primary healthcare settings.

Materials and Methods

The AGT was applied to 700 eyes of 355 people aged 50 and over who applied to a family health center in Ankara and had no eye complaints. The test was considered positive if the lines on the AGT card were seen as broken or curved, there was a difference in shape or size between the squares, or a color change or blurring was described in any area. An ophthalmologist was consulted if the AGT was positive in one or both eyes. Patients considered suitable by ophthalmologists were evaluated with optical coherence tomography. AGT results were compared with ophthalmologist examination and tomography findings in terms of AMD detection.

Results

The AGT was positive in 97 (13.9%) and negative in 603 (86.1%) out of 700 eyes included in the study. A total of 184 eyes, 79 with a positive AGT and 105 eyes with a negative test, were evaluated by an ophthalmologist. As a result of examinations and tests performed by ophthalmologists, AMD was detected in a total of 67 eyes: 42 of 79 eyes with positive AGT and 25 of 105 eyes with negative AGT but referred to an ophthalmologist for different reasons. In our study, the AGT had 62.7% sensitivity and 68.4% specificity.

Conclusion

The AGT is an inexpensive and easily applicable test. Although moderate sensitivity and specificity were found in our study; further studies are needed to evaluate the suitability of its use for AMD screening in primary care with limited facilities.

The Surprising Nonlinear Effects of S100A9 Proteins in the Retina

Age-related macular degeneration (AMD) is a complex disease in which inflammation is implicated as a key factor but the precise molecular mechanisms are poorly understood. AMD lesions contain an excess of the pro-inflammatory S100A9 protein, but its retinal significance was yet unexplored. S100A9 was shown to be intrinsically amyloidogenic in vitro and in vivo. Here, we hypothesized that the retinal effects of S100A9 are related to its supramolecular conformation. ARPE-19 cultures were treated with native dimeric and fibrillar S100A9 preparations, and cell viability was determined. Wild-type rats were treated intravitreally with the S100A9 solutions in the right eye and with the vehicle in the left. Retinal function was assessed longitudinally by electroretinography (ERG), comparing the amplitudes and configurations for each intervention. Native S100A9 had no impact on cellular viability in vitro or on the retinal function in vivo. Despite dispersed intracellular uptake, fibrillar S100A9 did not decrease ARPE-19 cell viability. In contrast, S100A9 fibrils impaired retinal function in vivo following intravitreal injection in rats. Intriguingly, low-dose fibrillar S100A9 induced contrasting in vivo effects, significantly increasing the ERG responses, particularly over 14 days postinjection. The retinal effects of S100A9 were further characterized by glial and microglial cell activation. We provide the first indication for the retinal effects of S100A9, showing that its fibrils inflicted retinal dysfunction and glial activation in vivo, while low dose of the same assemblies resulted in an unpredicted enhancement of the ERG amplitudes. These nonlinear responses highlight the consequences of self-assembly of S100A9 and provide insight into its pathophysiological and possibly physiological roles in the retina.

PFKFB3 in neovascular eye disease: unraveling mechanisms and exploring therapeutic strategies

BACKGROUND

Neovascular eye disease is characterized by pathological neovascularization, with clinical manifestations such as intraocular exudation, bleeding, and scar formation, ultimately leading to blindness in millions of individuals worldwide. Pathologic ocular angiogenesis often occurs in common fundus diseases including proliferative diabetic retinopathy (PDR), age-related macular degeneration (AMD), and retinopathy of prematurity (ROP). Anti-vascular endothelial growth factor (VEGF) targets the core pathology of ocular angiogenesis.

MAIN BODY

In recent years, therapies targeting metabolism to prevent angiogenesis have also rapidly developed, offering assistance to patients with a poor prognosis while receiving anti-VEGF therapy and reducing the side effects associated with long-term VEGF usage. Phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3), a key enzyme in targeted metabolism, has been shown to have great potential, with antiangiogenic effects and multiple protective effects in the treatment of neovascular eye disease. In this review, we summarize the mechanisms of common types of neovascular eye diseases; discuss the protective effect and potential mechanism of targeting PFKFB3, including the related inhibitors of PFKFB3; and look forward to the future exploration directions and therapeutic prospects of PFKFB3 in neovascular eye disease.

CONCLUSION

Neovascular eye disease, the most common and severely debilitating retinal disease, is largely incurable, necessitating the exploration of new treatment methods. PFKFB3 has been shown to possess various potential protective mechanisms in treating neovascular eye disease. With the development of several drugs targeting PFKFB3 and their gradual entry into clinical research, targeting PFKFB3-mediated glycolysis has emerged as a promising therapeutic approach for the future of neovascular eye disease.

Pan-cancer analysis of RNA 5-methylcytosine reader (ALYREF)

The increasing interest in RNA modifications has significantly advanced epigenomic and epitranscriptomic technologies. This study focuses on the immuno-oncological impact of ALYREF in human cancer through a pan-cancer analysis, enhancing understanding of this gene's role in cancer. We observed differential ALYREF expression between tumor and normal samples, correlating strongly with prognosis in various cancers, particularly kidney renal papillary cell carcinoma (KIRP) and liver hepatocellular carcinoma (LIHC). ALYREF showed a negative correlation with most tumor-infiltrating cells in lung squamous cell carcinoma (LUSC) and lymphoid neoplasm diffuse large B-cell lymphoma (DLBC), while positive correlations were noted in LIHC, kidney chromophobe (KICH), mesothelioma (MESO), KIRP, pheochromocytoma and paraganglioma (PARD), and glioma (GBMLGG). Additionally, ALYREF expression was closely associated with tumor heterogeneity, stemness indices, and a high mutation rate in TP53 across these cancers. In conclusion, ALYREF may serve as an oncogenic biomarker in numerous cancers, meriting further research attention.

A Cataract-Causing Mutation in the TRPM3 Cation Channel Disrupts Calcium Dynamics in the Lens

TRPM3 belongs to the melastatin sub-family of transient receptor potential (TRPM) cation channels and has been shown to function as a steroid-activated, heat-sensitive calcium ion (Ca2+) channel. A missense substitution (p.I65M) in the TRPM3 gene of humans (TRPM3) and mice (Trpm3) has been shown to underlie an inherited form of early-onset, progressive cataract. Here, we model the pathogenetic effects of this cataract-causing mutation using 'knock-in' mutant mice and human cell lines. Trpm3 and its intron-hosted micro-RNA gene (Mir204) were strongly co-expressed in the lens epithelium and other non-pigmented and pigmented ocular epithelia. Homozygous Trpm3-mutant lenses displayed elevated cytosolic Ca2+ levels and an imbalance of sodium (Na+) and potassium (K+) ions coupled with increased water content. Homozygous TRPM3-mutant human lens epithelial (HLE-B3) cell lines and Trpm3-mutant lenses exhibited increased levels of phosphorylated mitogen-activated protein kinase 1/extracellular signal-regulated kinase 2 (MAPK1/ERK2/p42) and MAPK3/ERK1/p44. Mutant TRPM3-M65 channels displayed an increased sensitivity to external Ca2+ concentration and an altered dose response to pregnenolone sulfate (PS) activation. Trpm3-mutant lenses shared the downregulation of genes involved in insulin/peptide secretion and the upregulation of genes involved in Ca2+ dynamics. By contrast, Trpm3-deficient lenses did not replicate the pathophysiological changes observed in Trpm3-mutant lenses. Collectively, our data suggest that a cataract-causing substitution in the TRPM3 cation channel elicits a deleterious gain-of-function rather than a loss-of-function mechanism in the lens.

Face Recognition Characteristics in Patients with Age-Related Macular Degeneration Determined Using a Virtual Reality Headset with Eye Tracking

BACKGROUND AND OBJECTIVES

Face recognition is one of the most serious disabilities of patients with age-related macular degeneration (AMD). Our purpose was to study face recognition using a novel method incorporating virtual reality (VR) and eye tracking.

MATERIALS AND METHODS

Eighteen patients with AMD (seven male; median age 83 years; 89% with bilateral advanced AMD) and nineteen healthy controls (five male; median age 68 years) underwent the face recognition test IC FACES (Synthesius, Ljubljna, Slovenia) on a VR headset with built-in eye tracking sensors. Analysis included recognition accuracy, recognition time and fixation patterns. Additionally, a screening test for dementia and imaging with fundus autofluorescence and optical coherence tomography was performed.

RESULTS

AMD patients had significantly lower face recognition accuracy (42% vs. 92%; p < 0.001) and longer recognition time (median 4.0 vs. 2.0 s; p < 0.001) in comparison to controls. Both parameters were significantly worse in patients with lower visual acuity. In both groups, eye-tracking data revealed the two classical characteristics of the face recognition process, i.e., fixations clustering mainly in the nose-eyes-mouth triangle and starting observation in the nasal area.

CONCLUSIONS

The study demonstrates usability of a VR headset with eye tracking for studying visual perception in real-world situations which could be applicable in the design of clinical studies.

Microglia depletion/repopulation does not affect light-induced retinal degeneration in mice

Reactive microglia are a hallmark of age-related retinal degenerative diseases including age-related macular degeneration (AMD). These cells are capable of secreting neurotoxic substances that may aggravate inflammation that leads to loss of photoreceptors and impaired vision. Despite their role in driving detrimental inflammation, microglia also play supporting roles in the retina as they are a crucial cellular component of the regulatory innate immune system. In this study, we used the colony stimulating factor 1 receptor (CSF1R)-antagonist PLX3397 to investigate the effects of microglia depletion and repopulation in a mouse model of acute retinal degeneration that mimics some aspects of dry AMD. Our main goal was to investigate whether microglia depletion and repopulation affects the outcome of light-induced retinal degeneration. We found that microglia depletion effectively decreased the expression of several key pro-inflammatory factors but was unable to influence the extent of retinal degeneration as determined by optical coherence tomography (OCT) and histology. Interestingly, we found prominent cell debris accumulation in the outer retina under conditions of microglia depletion, presumably due to the lack of efficient phagocytosis that could not be compensated by the retinal pigment epithelium. Moreover, our in vivo experiments showed that renewal of retinal microglia by repopulation did also not prevent rapid microglia activation or preserve photoreceptor death under conditions of light damage. We conclude that microglia ablation strongly reduces the expression of pro-inflammatory factors but cannot prevent photoreceptor loss in the light-damage paradigm of retinal degeneration.

Ranibizumab Modifies the Expression of Metalloproteinases and Their Tissue Inhibitors in Peripheral Blood Mononuclear Cells in Patients with Exudative Age-Related Macular Degeneration

BACKGROUND

Age-related macular degeneration (AMD) is the leading cause of vision loss in people over 60 years of age. Despite research, the causes of AMD remain unclear. Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) are known to be involved in AMD development, and anti-vascular endothelial growth factor therapy has revolutionized its treatment. This study aims to analyze the changes in gene expression in MMPs and TIMPS in patients with neovascular AMD before and after three doses of ranibizumab.

METHODS

The study involved 29 patients with neovascular AMD treated with ranibizumab. Peripheral blood mononuclear cells were collected before treatment and 24 h after the third dose of ranibizumab. We assessed MMP and TIMP gene expression profiles through oligonucleotide microarrays and validated selected differential genes using RT-qPCR.

RESULTS

A statistically significant change in the expression of six MMP- and TIMP-related genes was observed using oligonucleotide microarray. The mRNA levels of the two genes with the most significant fold changes, MMP15 and TIMP2, were then quantified using RT-qPCR. The results confirmed a statistically significant increase in MMP15 expression and a decrease in TIMP2 levels, although this change was not statistically significant in the group before and after the third dose of ranibizumab.

CONCLUSION

Ranibizumab affects the systemic expression of MMP and TIMP-related genes in patients with neovascular AMD. Results from our exploratory study suggest that MMP15, in particular, may play a role in the treatment response, but further research is necessary.

Fluorescence Lifetime Imaging Ophthalmoscopy of Mouse Models of Age-related Macular Degeneration

Purpose

To investigate fluorescence lifetime of mouse models of age-related macular degeneration (AMD) by fluorescence lifetime imaging ophthalmoscopy (FLIO).

Methods

Two AMD mouse models, apolipoprotein E knockout (ApoE-/-) mice and NF-E2-related factor-2 knockout (Nrf2-/-) mice, and their wild-type mice underwent monthly ophthalmic examinations including FLIO from 3 months of age. After euthanasia at the age of 6 or 11 months, blood plasma was collected to determine total antioxidant capacity and eyes were enucleated for Oil red O (ORO) lipid staining of chorioretinal tissue.

Results

In FLIO, the mean fluorescence lifetime (τm) of wild type shortened with age in both spectral channels. In short spectral channel, τm shortening was observed in both AMD models as well, but its rate was more pronounced in ApoE-/- mice and significantly different from the other strains as months of age progressed. In contrast, in long spectral channel, both model strains showed completely opposite trends, with τm becoming shorter in ApoE-/- and longer in Nrf2-/- mice than the others. Oil red O staining at Bruch's membrane was significantly stronger in ApoE-/- mice at 11 months than the other strains. Plasma total antioxidant capacity was highest in ApoE-/- mice at both 6 and 11 months.

Conclusions

The two AMD mouse models exhibited largely different fundus fluorescence lifetime, which might be related to the different systemic metabolic state. FLIO might be able to indicate different metabolic states of eyes at risk for AMD.

Translational Relevance

This animal study may provide new insights into the relationship between early AMD-associated metabolic changes and FLIO findings.

Dysregulation of histone deacetylases in ocular diseases

Ocular diseases are a growing global concern and have a significant impact on the quality of life. Cataracts, glaucoma, age-related macular degeneration, and diabetic retinopathy are the most prevalent ocular diseases. Their prevalence and the global market size are also increasing. However, the available pharmacotherapy is currently limited. These diseases share common pathophysiological features, including neovascularization, inflammation, and/or neurodegeneration. Histone deacetylases (HDACs) are a class of enzymes that catalyze the removal of acetyl groups from lysine residues of histone and nonhistone proteins. HDACs are crucial for regulating various cellular processes, such as gene expression, protein stability, localization, and function. They have also been studied in various research fields, including cancer, inflammatory diseases, neurological disorders, and vascular diseases. Our study aimed to investigate the relationship between HDACs and ocular diseases, to identify a new strategy for pharmacotherapy. This review article explores the role of HDACs in ocular diseases, specifically focusing on diabetic retinopathy, age-related macular degeneration, and retinopathy of prematurity, as well as optic nerve disorders, such as glaucoma and optic neuropathy. Additionally, we explore the interplay between HDACs and key regulators of fibrosis and angiogenesis, such as TGF-β and VEGF, highlighting the potential of targeting HDAC as novel therapeutic strategies for ocular diseases.

Evaluation of systemic immune-inflammatory index in patients with wet age-related macular degeneration

CLINICAL RELEVANCE

The systemic immune-inflammatory index is a relatively new parameter and has been shown to increase in inflammatory diseases.

BACKGROUND

The primary aim of this study was to investigate the systemic immune-inflammatory index in patients with wet-type age-related macular degeneration. The secondary aim was to determine the relationship between best-corrected visual acuity, central macular thickness, subfoveal choroidal thickness, systemic immune-inflammatory index, platelet-to-lymphocyte ratio, and neutrophil-to-lymphocyte ratio.

METHODS

This study retrospectively analysed patients with wet-type age-related macular degeneration between 2018 and 2022. Demographic data and peripheral complete blood count were obtained from the electronic medical record system. The most recent best-corrected visual acuity, central macular thickness, and subfoveal choroidal thickness values (within one month) for complete blood count were obtained from case sheets and the optical coherence tomography digital image database. The systemic immune-inflammatory index, neutrophil-to-lymphocyte ratio, and platelet-to-lymphocyte ratio were calculated. Age- and sex-matched controls were also generated.

RESULTS

Thirty-three patients (23 males, 10 females) with wet-type age-related macular degeneration and 43 controls (24 males, 19 females) were included. The groups were similar in terms of age and sex (78.0 ± 6.3 vs. 75.6 ± 6.6 years, p = 0.59; p = 0.38 for sex). The systemic immune-inflammatory index was higher in the wet-type age-related macular degeneration group (460.5 vs. 440.4); however, this difference was not statistically significant. When the correlations between the systemic immune-inflammatory index, platelet-to-lymphocyte ratio, neutrophil-to-lymphocyte ratio, best-corrected visual acuity (logMAR), central macular thickness, and subfoveal choroidal thickness were examined, there was only a moderate positive correlation between best-corrected visual acuity and platelet-to-lymphocyte ratio (r = 0.46, p = 0.007).

CONCLUSION

There were no differences in the systemic immune-inflammatory index, neutrophil-to-lymphocyte ratio, and platelet-to-lymphocyte ratio between the wet-type age-related macular degeneration and control groups. There was a positive correlation between the platelet-to-lymphocyte ratio and best-corrected visual acuity (logMAR). The systemic immune-inflammatory index was higher in patients with wet-type age-related macular degeneration than in the control group; however, this difference was not statistically significant.

Crocetin inhibits choroidal neovascularization in both in vitro and in vivo models

Choroidal neovascularization (CNV) is the primary pathogenic process underlying wet age-related macular degeneration, leading to severe vision loss. Despite current anti-vascular endothelial growth factor (VEGF) therapies, several limitations persist. Crocetin, a major bioactive constituent of saffron, exhibits multiple pharmacological activities, yet its role and mechanism in CNV remain unclear. Here, we investigated the potential effects of crocetin on CNV using in vitro and in vivo models. In human umbilical vein endothelial cells, crocetin demonstrated inhibition of VEGF-induced cell proliferation, migration, and tube formation in vitro, as assessed by CCK-8 and EdU assays, transwell and scratch assays, and tube formation analysis. Additionally, crocetin suppressed choroidal sprouting in ex vivo experiments. In the human retinal pigment epithelium (RPE) cell line ARPE-19, crocetin attenuated cobalt chloride-induced hypoxic cell injury, as evidenced by CCK-8 assay. As evaluated by quantitative PCR and Western blot assay, it also reduced hypoxia-induced expression of VEGF and hypoxia-inducible factor 1α (HIF-1α), while enhancing zonula occludens-1 expression. In a laser-induced CNV mouse model, intravitreal administration of crocetin significantly reduced CNV size and suppressed elevated expressions of VEGF, HIF-1α, TNFα, IL-1β, and IL-6. Moreover, crocetin treatment attenuated the elevation of phospho-S6 in laser-induced CNV and hypoxia-induced RPE cells, suggesting its potential anti-angiogenic effects through antagonizing the mechanistic target of rapamycin complex 1 (mTORC1) signaling. Our findings indicate that crocetin may hold promise as an effective drug for the prevention and treatment of CNV.

AMD and Stem Cell-Based Therapies

Age-related macular degeneration (AMD) is a prevalent and complex disease leading to severe vision loss. Stem cells offer promising prospects for AMD treatment as they can be differentiated into critical retinal cell types that could replace lost host retinal cells or provide trophic support to promote host retinal cell survival. However, challenges such as immune rejection, concerns regarding tumorigenicity, and genomic integrity must be addressed. Clinical trials with stem cell-derived retinal pigment epithelial cells have shown preliminary safety in treating dry AMD, but improvements in manufacturing and surgical techniques cell delivery are needed. Late-stage AMD poses additional hurdles, possibly requiring multi-layered grafts. Advancements in automation technologies and gene correction strategies show potential to enhance iPSC-based therapies. Stem cell-based treatments offer hope for AMD management, but further research and optimization are essential for successful clinical implementation.

Association of STAT4 Gene Polymorphisms (rs10181656, rs7574865, rs7601754, rs10168266) and Serum STAT4 Levels in Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is a progressive degenerative disease that affects the central part of the retina: the macula. AMD is the most common cause of central vision loss in industrialized countries. Increasing attention is being paid to the study of genetic factors that may influence the manifestation of AMD. STAT4 protein is involved in the pathogenesis of numerous inflammatory processes, so we decided to investigate the association between STAT4 gene polymorphisms (rs10181656, rs7574865, rs7601754, and rs10168266) and age-related macular degeneration.

PURPOSE

To investigate the association between STAT4 (rs10181656, rs7574865, rs7601754, and rs10168266) gene polymorphisms and STAT4 serum levels in patients with age-related macular degeneration.

METHODS AND PARTICIPANTS

The study included 150 individuals with early AMD, 150 individuals with exudative AMD, and 200 healthy subjects. DNA was extracted from peripheral blood leukocytes using the DNA salting-out method, and the genotyping was performed using a real-time polymerase chain reaction (RT-PCR) method. STAT4 serum levels were evaluated using the ELISA method. Statistical analysis was performed using "IBM SPSS "Statistics 29.0" software".

RESULTS

The study revealed no statistically significant differences in the distribution of genotypes and alleles for the STAT4 polymorphisms (rs10181656, rs7574865, rs7601754, and rs10168266) between patients with AMD and the control group. Similarly, a gender-based analysis did not yield any significant differences in the genotype or allele frequencies. Age group comparisons also showed no statistically significant variations in the presence of these STAT4 polymorphisms between AMD patients and the control group. However, notably, individuals with exudative AMD displayed lower levels of serum STAT4 in comparison to the control group (median (IQR): 0.118 (0.042) vs. 0.262 (0.385), p = 0.005).

CONCLUSION

Investigating STAT4 gene polymorphisms (rs10181656, rs7574865, rs7601754, and rs10168266) did not reveal a significant association with AMD. However, further analysis demonstrated intriguing findings regarding serum STAT4 levels. Exudative AMD patients with at least one G allele of the STAT4 rs10181656 exhibited significantly lower serum STAT4 levels than the control group subjects (p = 0.011). Similarly, those with at least one T allele of STAT4 rs10168266 had lower serum STAT4 levels compared to the control group subjects (p = 0.039). These results suggest a potential link between specific STAT4 genotypes and serum STAT4 levels in exudative AMD patients, shedding light on a novel aspect of the disease.

Systematic review and meta-analysis of mass spectrometry proteomics applied to ocular fluids to assess potential biomarkers of age-related macular degeneration

BACKGROUND

Age-related macular degeneration (AMD) is a significant cause of severe vision loss. The main purpose of this study was to identify mass spectrometry proteomics-based potential biomarkers of AMD that contribute to understanding the mechanisms of disease and aiding in early diagnosis.

METHODS

This study retrieved studies that aim to detect differences relate to proteomics in AMD patients and healthy control groups by mass spectrometry (MS) proteomics approaches. The search process was accord with PRISMA guidelines (PROSPERO database: CRD42023388093). Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes Pathway Analysis (KEGG) were performed on differentially expressed proteins (DEPs) in the included articles using the DAVID database. DEPs were included in a meta-analysis when their effect size could be computed in at least two research studies. The effect size of measured proteins was transformed to the log2-fold change. Protein‒protein interaction (PPI) analysis was conducted on proteins that were statistically significant in the meta-analysis using the String online database.

RESULTS

Eleven studies fulfilled the inclusion criteria, and 161 DEPs were identified. The GO analysis showed that AMD is significantly related to proteolysis, extracellular exosome and protein binding. In KEGG, the most significant pathway was the complement and coagulation cascades. Meta-analysis results suggested that eight proteins were statistically significant, and according to PPI results, the most significant four proteins were serotransferrin (TF), apolipoprotein A1 (APOA1), complement C3 (C3) and lipocalin-1 (LCN1).

CONCLUSIONS

Four possible biomarkers, TF, APOA1, C3 and LCN1, were found to be significant in the pathogenesis of AMD and need to be further validated. Further studies should be performed to evaluate diagnostic and therapeutic value of these proteins.

Biomarkers for the Progression of Intermediate Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is a leading cause of severe vision loss worldwide, with a global prevalence that is predicted to substantially increase. Identifying early biomarkers indicative of progression risk will improve our ability to assess which patients are at greatest risk of progressing from intermediate AMD (iAMD) to vision-threatening late-stage AMD. This is key to ensuring individualized management and timely intervention before substantial structural damage. Some structural biomarkers suggestive of AMD progression risk are well established, such as changes seen on color fundus photography and more recently optical coherence tomography (drusen volume, pigmentary abnormalities). Emerging biomarkers identified through multimodal imaging, including reticular pseudodrusen, hyperreflective foci, and drusen sub-phenotypes, are being intensively explored as risk factors for progression towards late-stage disease. Other structural biomarkers merit further research, such as ellipsoid zone reflectivity and choriocapillaris flow features. The measures of visual function that best detect change in iAMD and correlate with risk of progression remain under intense investigation, with tests such as dark adaptometry and cone-specific contrast tests being explored. Evidence on blood and plasma markers is preliminary, but there are indications that changes in levels of C-reactive protein and high-density lipoprotein cholesterol may be used to stratify patients and predict risk. With further research, some of these biomarkers may be used to monitor progression. Emerging artificial intelligence methods may help evaluate and validate these biomarkers; however, until we have large and well-curated longitudinal data sets, using artificial intelligence effectively to inform clinical trial design and detect outcomes will remain challenging. This is an exciting area of intense research, and further work is needed to establish the most promising biomarkers for disease progression and their use in clinical care and future trials. Ultimately, a multimodal approach may yield the most accurate means of monitoring and predicting future progression towards vision-threatening, late-stage AMD.

[Relationship between treatment and cost with visual acuity improvement in age-related macular degeneration]

BACKGROUND

We examined the relationship between visual acuity changes (VA) and the cost of care and treatment with anti-vascular endothelial growth factors (antiVEGF) in patients diagnosed with age-related exudative macular degeneration (exudative AMD).

METHODS

Observational, longitudinal, retrospective study of patients ≥50 years of age diagnosed with exudative AMD, with a log-MAR VA between 0.6 and 0.06. and 0.06. Follow-up and treatment were done in our tertiary hospital between January 1, 2014 and December 31, 2018.

RESULTS

The study included 778 patients; 62.2% female and mean age 79.83±7.94 years; 957 eyes had exudative AMD. Mean of final VA (0.65±0.45) increasing 3.2% compared to initial values. Ranibizumab was administered to 60.3% of the eyes, aflibercept to 10.2% and ranibizumab + aflibercept (mixed group) to 29.5%. Significant increase in VA was seen in the group with the mixed treatment, with no inter-group differences. Although follow-up/treatment was longer for the mixed group, they received fewer anti-VEGF injections and optical coherence tomography (OCT). The total expenditure per year and treated eye was € 1,972.7±824.5; costs were higher for visit, OCT, and treatment in the aflibercept group, and lower for fluorescein angiography, antiVEGF treatment, and total costs in the mixed group. Decimal VA gain had a cost of € 872±1,077.7 with no significant inter-group differences.

CONCLUSIONS

AntiVEGF treatments (ranibizumab, aflibercept, or both) maintained VA in patients with exudative AMD. Overall, care and treatment costs were lower in the group that received both drugs.

Retinal pigment epithelium-Bruch's membrane volume in grading of age-related macular degeneration

AIM

To assess the agreement of optical coherence tomography (OCT) algorithm-based retinal pigment epithelium -Bruch's membrane complex volume (RBV) with fundus photograph-based age-related macular degeneration (AMD) grading.

METHODS

Digital color fundus photographs (CFPs) and spectral domain OCT images were acquired from 96 elderly subjects. CFPs were graded according to Age-Related Eye Disease Study (AREDS) classification. OCT image segmentation and RBV data calculation were done with Orion™ software. Univariate and multivariate analyses were performed to find out whether AMD lesion features associated with higher RBVs.

RESULTS

RBV correlated with AMD grading (rs=0.338, P=0.001), the correlation was slightly stronger in early AMD (n=52; rs=0.432, P=0.001). RBV was higher in subjects with early AMD compared with those with no AMD lesions evident in fundus photographs (1.05±0.20 vs 0.96±0.13 mm3, P=0.023). In multivariate analysis higher RBVs were associated significantly with higher total drusen (β=0.388, P=0.027) and pigmentation areas (β=0.319, P=0.020) in fundus photographs, whereas depigmentation area (β=-0.295, P=0.015) associated with lower RBV.

CONCLUSION

RBV correlate with AMD grading status, with a stronger association in patients with moderate, non-late AMD grades. This effect is driven mostly by lesions with drusen or pigmentation. Lesions with depigmentation tend to have lower values. RBV is more comprehensive measurement of the key area of AMD pathogenesis, compared to sole drusen volume analysis. RBV measurements are independent on grader variations and offer a possibility to quantify early and middle grade AMD lesions in a research setting, but may not substitute fundus photograph-based grading in the whole range of AMD spectrum.

"Application and accuracy of artificial intelligence-derived large language models in patients with age related macular degeneration"

INTRODUCTION

Age-related macular degeneration (AMD) affects millions of people globally, leading to a surge in online research of putative diagnoses, causing potential misinformation and anxiety in patients and their parents. This study explores the efficacy of artificial intelligence-derived large language models (LLMs) like in addressing AMD patients' questions.

METHODS

ChatGPT 3.5 (2023), Bing AI (2023), and Google Bard (2023) were adopted as LLMs. Patients' questions were subdivided in two question categories, (a) general medical advice and (b) pre- and post-intravitreal injection advice and classified as (1) accurate and sufficient (2) partially accurate but sufficient and (3) inaccurate and not sufficient. Non-parametric test has been done to compare the means between the 3 LLMs scores and also an analysis of variance and reliability tests were performed among the 3 groups.

RESULTS

In category a) of questions, the average score was 1.20 (± 0.41) with ChatGPT 3.5, 1.60 (± 0.63) with Bing AI and 1.60 (± 0.73) with Google Bard, showing no significant differences among the 3 groups (p = 0.129). The average score in category b was 1.07 (± 0.27) with ChatGPT 3.5, 1.69 (± 0.63) with Bing AI and 1.38 (± 0.63) with Google Bard, showing a significant difference among the 3 groups (p = 0.0042). Reliability statistics showed Chronbach's α of 0.237 (range 0.448, 0.096-0.544).

CONCLUSION

ChatGPT 3.5 consistently offered the most accurate and satisfactory responses, particularly with technical queries. While LLMs displayed promise in providing precise information about AMD; however, further improvements are needed especially in more technical questions.

Targeting 7KCh-Induced Cell Death Response Mediated by p38, P2X7 and GSDME in Retinal Pigment Epithelium Cells with Sterculic Acid

Age-related macular degeneration (AMD) is the main cause of blindness in developed countries. AMD is characterized by the formation of drusen, which are lipidic deposits, between retinal pigment epithelium (RPE) and the choroid. One of the main molecules accumulated in drusen is 7-Ketocholesterol (7KCh), an oxidized-cholesterol derivative. It is known that 7KCh induces inflammatory and cytotoxic responses in different cell types and the study of its mechanism of action is interesting in order to understand the development of AMD. Sterculic acid (SA) counteracts 7KCh response in RPE cells and could represent an alternative to improve currently used AMD treatments, which are not efficient enough. In the present study, we determine that 7KCh induces a complex cell death signaling characterized by the activation of necrosis and an alternative pyroptosis mediated by P2X7, p38 and GSDME, a new mechanism not yet related to the response to 7KCh until now. On the other hand, SA treatment can successfully attenuate the activation of both necrosis and pyroptosis, highlighting its therapeutic potential for the treatment of AMD.

Dynamic human retinal pigment epithelium (RPE) and choroid architecture based on single-cell transcriptomic landscape analysis

The retinal pigment epithelium (RPE) and choroid are located behind the human retina and have multiple functions in the human visual system. Knowledge of the RPE and choroid cells and their gene expression profiles are fundamental for understanding retinal disease mechanisms and therapeutic strategies. Here, we sequenced the RNA of about 0.3 million single cells from human RPE and choroids across two regions and seven ages, revealing regional and age differences within the human RPE and choroid. Cell-cell interactions highlight the broad connectivity networks between the RPE and different choroid cell types. Moreover, the transcription factors and their target genes change during aging. The coding of somatic variations increases during aging in the human RPE and choroid at the single-cell level. Moreover, we identified ELN as a candidate for improving RPE degeneration and choroidal structure during aging. The mapping of the molecular architecture of the human RPE and choroid improves our understanding of the human vision support system and offers potential insights into the intervention targets for retinal diseases.

Systemic Dendrimer-Peptide Therapies for Wet Age-Related Macular Degeneration

Wet age-related macular degeneration (AMD) is an end-stage event in a complex pathogenesis of macular degeneration, involving the abnormal growth of blood vessels at the retinal pigment epithelium driven by vascular endothelial growth factor (VEGF). Current therapies seek to interrupt VEGF signaling to halt the progress of neovascularization, but a significant patient population is not responsive. New treatment modalities such as integrin-binding peptides (risuteganib/Luminate/ALG-1001) are being explored to address this clinical need but these treatments necessitate the use of intravitreal injections (IVT), which carries risks of complications and restricts its availability in less-developed countries. Successful systemic delivery of peptide-based therapeutics must overcome obstacles such as degradation by proteinases in circulation and off-target binding. In this work, we present a novel dendrimer-integrin-binding peptide (D-ALG) synthesized with a noncleavable, "clickable" linker. In vitro, D-ALG protected the peptide payload from enzymatic degradation for up to 1.5 h (~90% of the compound remained intact) in a high concentration of proteinase (2 mg/mL) whereas ~90% of free ALG-1001 was degraded in the same period. Further, dendrimer conjugation preserved the antiangiogenic activity of ALG-1001 in vitro with significant reductions in endothelial vessel network formation compared to untreated controls. In vivo, direct intravitreal injections of ALG-1001 and D-ALG produced reductions in the CNV lesion area but in systemically dosed animals, only D-ALG produced significant reductions of CNV lesion area at 14 days. Imaging data suggested that the difference in efficacy may be due to more D-ALG remaining in the target area than ALG-1001 after administration. The results presented here offer a clinically relevant route for peptide therapeutics by addressing the major obstacles that these therapies face in delivery.

Age-Related Macular Degeneration in Patients with Androgenetic Alopecia: Could the Monocyte/HDL Ratio Be the Link?

INTRODUCTION

Both Androgenetic alopecia (AGA) and age-related macular degeneration (AMD) shared the microinflammatory milieu and increased oxidative stress as important criteria in their pathogenesis. The monocyte/high density lipoprotein (HDL) ratio (MHR) seems to be an easy-to-calculate prognostic marker of microinflammation.

OBJECTIVES

To assess MHR in patients with AGA and its correlation to AMD in these patients, if any.

METHODS

Forty patients with AGA aged 40 years or more of both sexes and 40 control subjects participated in this case-control study. General, dermatological, and ophthalmologic examination, MHR evaluation and optical coherence tomography (OCT) were performed.

RESULTS

The mean MHR was significantly higher in AGA patients (6.98 ± 2.21) than in controls (3.82 ± 0.68) (P < 0.001). AMD was significantly higher in patients than controls (P < 0.001). Eighty percent of AGA patients were diagnosed with AMD versus 20% of control subjects. The presence of AMD in AGA was significantly related to the degree of severity of AGA in male patients (P = 0.02). The MHR was significantly higher in AGA patients found to have AMD (9.37 ± 1.1 and 7.01 ± 1.42 in the wet and dry type respectively) than those without AMD (P < 0.001).

CONCLUSIONS

AMD may develop more frequently in those with AGA. The MHR seems to be a missing link between both conditions, and could be utilized as a potential biomarker for predicting AMD in AGA patients.

Clinical efficacy and changes of serum VEGF-A, VEGF-B, and PLGF after conbercept treating neovascular age-related macular degeneration

AIM

To evaluate the clinical efficacy and systemic safety profile of conbercept in clinical practice on vascular endothelial growth factor (VEGF)-A, VEGF-B, and placental growth factor (PLGF) levels after intravitreal injections for the neovascular age-related macular degeneration (AMD).

METHODS

Thirty-five patients (35 eyes) with neovascular AMD received intravitreal injections of conbercept treatment with pro re nata protocol. Best-corrected visual acuity (BCVA) and central retinal thickness (CRT) were detected before the intravitreal injection and at 1, 3, and 12mo after conbercept treatment. The levels of serum VEGF-A, VEGF-B, and PLGF were measured by enzyme-linked immunosorbent assay before the injection and 1 and 12mo after conbercept treatments.

RESULTS

At baseline, the mean BCVA score was 39.89±14.64 letters. The mean BCVA scores were 51.03±15.78, 56.71±14.38, and 52.49±10.16 letters at 1, 3, and 12mo after conbercept treatment, and the BCVA improvements were all significant, respectively (P<0.05). At baseline, the mean CRT was 436.7±141.9 µm. At 1, 3, and 12mo after conbercept treatment, the mean CRT values were 335.1±147.8, 301.1±116.5, and 312.2±98.22 µm, and the CRT improvements were all significant, respectively (P<0.05). At baseline, 1 and 12mo after conbercept treatment, the mean levels of serum VEGF-A were 1013.8±454.3, 953.1±426.4, and 981.5±471.7 pg/mL, the mean levels of serum VEGF-B were 46.93±24.76, 42.99±19.16, and 45.32±18.76 pg/mL, the mean levels of serum PLGF at these points were 251.7±154.9, 241.3±166.7, and 245.6±147.2 pg/mL, respectively. Compared with the baseline, the levels of serum VEGF-A, VEGF-B, and PLGF did not significantly change at 1 and 12mo after conbercept treatment, respectively (P>0.05).

CONCLUSION

Conbercept intravitreal injection leads to BCVA and CRT improvement, however, it does not significantly affect systemic serum VEGF-A, VEGF-B, and PLGF levels at 1 and 12mo after intravitreal injection treating neovascular AMD.

Investigation of the choroidal structure in non-neovascular age-related macular degeneration patients with reticular pseudodrusen

BACKGROUND

This study aimed to compare choroidal thickness, total choroidal area (TCA), luminal area (LA), stromal area (SA) and choroidal vascularity index (CVI) in patients with reticular pseudodrusen (RPD) and drusen.

METHODS

A total of 100 eyes of 100 patients with non-neovascular age related macular degeneration (AMD) with five or more medium drusen (63-125 µm) and RPD in two or more quadrants were recruited to the study. 48 eyes of 48 patients with RPD were assigned as Group 1 and 52 eyes of 52 patients with drusen were assigned as Group 2. 40 right eyes of 40 healthy subjects were included as controls. Patients with neovascular AMD or advanced non-neovascular AMD were excluded from the study. After a detailed ophthalmic examination, infrared reflectance images and OCT with enhanced depth imaging mode was obtained from all patients. TCA, SA, LA and CVI were calculated using the Image J program. The data were analyzed for statistics using SPSS software.

RESULTS

The female/male ratio was 56/44 in the patient groups and 20/20 in the control group. The mean age was 73.63±6.14 (61-91) years for Group 1 and 69.43± 6.97 (59-87) years for Group 2 (p=0.005). The mean age of Group 3 patients was 71.14±8.17 (60-79) years and was statistically similar to Groups 1 and 2 (p=0.09 and p=0.12, respectively). Choroidal thickness, TCA, SA and LA were significantly lower in Group 1 (p<0.001). CVI and foveal thicknesses were not significantly different between Group 1 and 2 (p=0.214 and p=0.384 respectively). CVI was significantly lower in Group 3 (p<0.01). RPD was most commonly seen in the superior quadrant followed by temporal, nasal, and inferior quadrants.

CONCLUSIONS

TCA, SA and LA, which reflect choroidal vasculature, were decreased in patients with RPD. These parameters can help evaluate the pathophysiology of the disease.

Reprogramming iPSCs to study age-related diseases: Models, therapeutics, and clinical trials

The unprecedented rise in life expectancy observed in the last decades is leading to a global increase in the ageing population, and age-associated diseases became an increasing societal, economic, and medical burden. This has boosted major efforts in the scientific and medical research communities to develop and improve therapies to delay ageing and age-associated functional decline and diseases, and to expand health span. The establishment of induced pluripotent stem cells (iPSCs) by reprogramming human somatic cells has revolutionised the modelling and understanding of human diseases. iPSCs have a major advantage relative to other human pluripotent stem cells as their obtention does not require the destruction of embryos like embryonic stem cells do, and do not have a limited proliferation or differentiation potential as adult stem cells. Besides, iPSCs can be generated from somatic cells from healthy individuals or patients, which makes iPSC technology a promising approach to model and decipher the mechanisms underlying the ageing process and age-associated diseases, study drug effects, and develop new therapeutic approaches. This review discusses the advances made in the last decade using iPSC technology to study the most common age-associated diseases, including age-related macular degeneration (AMD), neurodegenerative and cardiovascular diseases, brain stroke, cancer, diabetes, and osteoarthritis.

Targeting the Gut-Eye Axis: An Emerging Strategy to Face Ocular Diseases

The human microbiota refers to a large variety of microorganisms (bacteria, viruses, and fungi) that live in different human body sites, including the gut, oral cavity, skin, and eyes. In particular, the presence of an ocular surface microbiota with a crucial role in maintaining ocular surface homeostasis by preventing colonization from pathogen species has been recently demonstrated. Moreover, recent studies underline a potential association between gut microbiota (GM) and ocular health. In this respect, some evidence supports the existence of a gut-eye axis involved in the pathogenesis of several ocular diseases, including age-related macular degeneration, uveitis, diabetic retinopathy, dry eye, and glaucoma. Therefore, understanding the link between the GM and these ocular disorders might be useful for the development of new therapeutic approaches, such as probiotics, prebiotics, symbiotics, or faecal microbiota transplantation through which the GM could be modulated, thus allowing better management of these diseases.

Identification of the Immune Landscapes and Follicular Helper T Cell-Related Genes for the Diagnosis of Age-Related Macular Degeneration

BACKGROUND

Age-related macular degeneration (AMD) is a progressive ocular ailment causing age-associated vision deterioration, characterized by dysregulated immune cell activity. Notably, follicular helper T (Tfh) cells have emerged as pivotal contributors to AMD pathogenesis. Nonetheless, investigations into Tfh-associated gene biomarkers for this disorder remain limited.

METHODS

Utilizing gene expression data pertinent to AMD procured from the Gene Expression Omnibus (GEO) repository, we employed the "DESeq2" R software package to standardize and preprocess expression levels. Concurrently, CIBERSORT analysis was utilized to compute the infiltration proportions of 22 distinct immune cell types. Subsequent to weighted gene correlation network analysis (WGCNA), coupled with differential expression scrutiny, we pinpointed genes intricately linked with Tfh cells. These potential genes underwent further screening using the MCODE function within Cytoscape software. Ultimately, a judicious selection of pivotal genes from these identified clusters was executed through the LASSO algorithm. Subsequently, a diagnostic nomogram was devised based on these selected genes.

RESULTS

Evident Tfh cell disparities between AMD and control cohorts were observed. Our amalgamated analysis, amalgamating differential expression data with co-expression patterns, unveiled six genes closely associated with Tfh cells in AMD. Subsequent employment of the LASSO algo-rithm facilitated identification of the most pertinent genes conducive to predictive modeling. From these, GABRB3, MFF, and PROX1 were elected as prospective diagnostic biomarkers for AMD.

CONCLUSIONS

This investigation discerned three novel biomarker genes, linked to inflammatory mechanisms and pivotal in diagnosing AMD. Further exploration of these genes holds potential to foster novel therapeutic modalities and augment comprehension of AMD's disease trajectory.

Circulating MicroRNAs as Biomarker for Vessel-Associated Retinal Diseases

INTRODUCTION

Vessel-associated retinal diseases are a major cause of blindness and severe visual impairment. The identification of appropriate biomarkers is of great importance to better anticipate disease progression and establish more targeted treatment options. MicroRNAs (miRNAs) are short, single-stranded, noncoding ribonucleic acids that are involved in the posttranscriptional regulation of gene expression through hybridization with messenger RNA. The expression of certain miRNAs can be different in patients with pathological processes and can be used for the detection and differentiation of various diseases. In this study, we investigate to what extent previously in vitro identified miRNAs are present as cell-free circulating miRNAs in the serum and vitreous of human patients with and without vessel-associated retinal diseases.

METHODS

Relative quantification by quantitative real-time polymerase chain reaction was used to analyze miRNA expression in patients with vessel-associated retinal diseases such as age-related macular degeneration (AMD), diabetic retinopathy (DR), and retinal vein occlusion compared with control patients.

RESULTS

In serum samples, miR-29a-3p and miR-192-5p showed increased expression in patients with neovascular AMD relative to control patients. Similarly, miR-335-5p, miR-192-5p, and miR-194-5p showed increased expression in serum from patients with proliferative DR. In vitreous samples, miR-100-5p was decreased in patients with proliferative DR. Differentially expressed miRNAs showed good diagnostic accuracy in receiver operating characteristic (ROC) and area under the ROC curve analysis.

CONCLUSION

The miRNAs investigated in this study may have the potential to serve as biomarkers for vessel-associated retinal diseases. Combining multiple miRNAs may enhance the predictive power of the analysis.

Electrochemical nano-biosensor based on electrospun indium zinc oxide nanofibers for the determination of complement component 3 protein

Age-related macular degeneration (AMD) is a progressive chronic neurodegenerative retinal disease leading to vision loss, irreversible blindness, and visual impairment in older adults worldwide. Complement component 3 (C3) protein has been identified as the most predominant biomarker towards early diagnosis of AMD; therefore, there is an utmost requirement for non-invasive detection of C3 protein in the tear fluids of AMD patients. Considering this, we report an insightful electrochemical sensor capable of detecting clinically relevant concentrations ranging from 10 fg/mL to 1 μg/mL using electrospun indium-doped zinc oxide (InZnO) nanofibers as the transducing layer. The InZnO nanofibers have facilitated high anti-C3 antibody loading of 3.42 × 10^-9 mol/cm² and enhanced the overall charge transport mechanism at the sensor interface. The biofunctionalization process of the biosensor was investigated thoroughly using X-ray photoelectron spectroscopy (XPS) as well as different electrochemical techniques. The target C3 proteins were captured on the fabricated biosensor surface and determined through changes in charge transfer resistance (R_CT) while executing electrochemical impedance spectroscopy (EIS) and peak current (I_p) in the case of cyclic voltammetry (CV) and differential pulse voltammetry (DPV), respectively. The InZnO nanofiber-based nano-biosensor demonstrated a very low limit of detections (LODs) of 5.214 fg/mL and 0.241 fg/mL with an excellent sensitivity of 4.6709 (ΔR/R) (g/mL)^-1 cm^-2 and 54.4939 (ΔI_p/I_p)% (g/mL)^-1 cm^-2 for EIS and DPV techniques, respectively. By virtue of high antibody loading, ultrasensitive and ultra-selective capability, the indium-doped ZnO nanofibers show huge potential to be used as a high-performance diagnostic platform for AMD diagnosis.