Age-Related Macular Degeneration

Cholesterol Accumulation Promotes Photoreceptor Senescence and Retinal Degeneration

Purpose

Dysregulated cholesterol metabolism is critical in the pathogenesis of AMD. Cellular senescence contributes to the development of numerous age-associated diseases. In this study, we investigated the link between cholesterol burden and the cellular senescence of photoreceptors.

Methods

Retinas from rod-specific ATP binding cassette subfamily A member 1 (Abca1) and G member 1 (Abcg1) (Abca1/g1-rod/-rod) knockout mice fed with a high-fat diet were analyzed for the signs of cellular senescence. Real-time quantitative PCR and immunofluorescence were used to characterize the senescence profile of the retina and cholesterol-treated photoreceptor cell line (661W). Inducible elimination of p16(Ink4a)-positive senescent cells (INK-ATTAC) mice or the administration of senolytic drugs (dasatinib and quercetin: D&Q) were used to examine the impact of senolytics on AMD-like phenotypes in Abca1/g1-rod/-rod retina.

Results

Increased accumulation of senescent cells as measured by markers of cellular senescence was found in Abca1/g1-rod/-rod retina. Exogenous cholesterol also induced cellular senescence in 661W cells. Selective elimination of senescent cells in Abca1/g1-rod/-rod;INK-ATTAC mice or by administration of D&Q improved visual function, lipid accumulation in retinal pigment epithelium, and Bruch's membrane thickening.

Conclusions

Cholesterol accumulation promotes cellular senescence in photoreceptors. Eliminating senescent photoreceptors improves visual function in a model of retinal neurodegeneration, and senotherapy offers a novel therapeutic avenue for further investigation.

Exploring ocular fibulin-3 (EFEMP1): Anatomical, age-related, and species perspectives

Fibulin-3 (FBLN3, aka EFEMP1) is a secreted extracellular matrix (ECM) glycoprotein implicated in ocular diseases including glaucoma and age-related macular degeneration. Yet surprisingly, little is known about its native biology, expression patterns, and localization in the eye. To overcome these shortcomings, we conducted gene expression analysis and immunohistochemistry for FBLN3 in ocular tissues from mice, pigs, non-human primates, and humans. Moreover, we evaluated age-related changes in FBLN3 and FBLN3-related ECM remodeling enzymes/inhibitors in aging mice. We found that FBLN3 displayed distinct staining patterns consistent across the mouse retina, particularly in the ganglion cell layer and inner nuclear layer (INL). In contrast, human retinas exhibited a unique staining pattern, with enrichment of FBLN3 in the retinal pigment epithelium (RPE), INL, and outer nuclear layer (ONL) in the peripheral retina. This staining transitioned to the outer plexiform layer (OPL) in the central retina/macula, and was accompanied by reduced RPE immunoreactivity approaching the fovea. Surprisingly, we found significant age-related increases in FBLN3 expression and protein abundance in the mouse retina which was paralleled by reduced transcript levels of FBLN3-degrading enzymes (i.e., Mmp2 and Htra1). Our findings highlight important species-dependent, retinal region-specific, and age-related expression and localization patterns of FBLN3 which favor its accumulation during aging. These findings contribute to a better understanding of FBLN3's role in ocular pathology and provide valuable insights for future FBLN3 research.

Fatty Acid-Binding Protein 4-Mediated Regulation Is Pivotally Involved in Retinal Pathophysiology: A Review

Fatty acid-binding proteins (FABPs), a family of lipid chaperone molecules that are involved in intracellular lipid transportation to specific cellular compartments, stimulate lipid-associated responses such as biological signaling, membrane synthesis, transcriptional regulation, and lipid synthesis. Previous studies have shown that FABP4, a member of this family of proteins that are expressed in adipocytes and macrophages, plays pivotal roles in the pathogenesis of various cardiovascular and metabolic diseases, including diabetes mellitus (DM) and hypertension (HT). Since significant increases in the serum levels of FABP4 were detected in those patients, FABP4 has been identified as a crucial biomarker for these systemic diseases. In addition, in the field of ophthalmology, our group found that intraocular levels of FABP4 (ioFABP4) and free fatty acids (ioFFA) were substantially elevated in patients with retinal vascular diseases (RVDs) including proliferative diabetic retinopathy (PDR) and retinal vein occlusion (RVO), for which DM and HT are also recognized as significant risk factors. Recent studies have also revealed that ioFABP4 plays important roles in both retinal physiology and pathogenesis, and the results of these studies have suggested potential molecular targets for retinal diseases that might lead to future new therapeutic strategies.

KIF11 UFMylation Maintains Photoreceptor Cilium Integrity and Retinal Homeostasis

The photoreceptor cilium is vital for maintaining the structure and function of the retina. However, the molecular mechanisms underlying the photoreceptor cilium integrity and retinal homeostasis are largely unknown. Herein, it is shown that kinesin family member 11 (KIF11) localizes at the transition zone (connecting cilium) of the photoreceptor and plays a crucial role in orchestrating the cilium integrity. KIF11 depletion causes malformations of both the photoreceptor ciliary axoneme and membranous discs, resulting in photoreceptor degeneration and the accumulation of drusen-like deposits throughout the retina. Mechanistic studies show that the stability of KIF11 is regulated by an interplay between its UFMylation and ubiquitination; UFMylation of KIF11 at lysine 953 inhibits its ubiquitination by synoviolin 1 and thereby prevents its proteasomal degradation. The lysine 953-to-arginine mutant of KIF11 is more stable than wild-type KIF11 and also more effective in reversing the ciliary and retinal defects induced by KIF11 depletion. These findings identify a critical role for KIF11 UFMylation in the maintenance of photoreceptor cilium integrity and retinal homeostasis.

Topographic analysis of local OCT biomarkers which predict progression to atrophy in age-related macular degeneration

PURPOSE

To define optical coherence tomography (OCT) biomarkers that precede the development of complete retinal pigment epithelium and outer retinal atrophy (cRORA) at that location in eyes with age-related macular degeneration (AMD).

METHODS

In this retrospective case-control study, patients with dry AMD who had evidence of cRORA and OCT data available for 4 years (48 ± 4 months) prior to the first visit with evidence of cRORA were included. The visit 4 years prior to the development of cRORA was defined as the baseline visit, and the region on the OCT B-scans of future cRORA development was termed the case region. A region in the same eye at the same distance from the foveal center as the case region that did not progress to cRORA was selected as the control region. OCT B-scans at the baseline visit through both the case and control regions were evaluated for the presence of soft and cuticular drusen, drusen with hyporeflective cores (hcD), drusenoid pigment epithelial detachments (PED), subretinal drusenoid deposits (SDD), thick and thin double-layer signs (DLS), intraretinal hyperreflective foci (IHRF), and acquired vitelliform lesions (AVL).

RESULTS

A total of 57 eyes of 41 patients with dry AMD and evidence of cRORA were included. Mean time from the baseline visit to the first visit with cRORA was 44.7 ± 6.5 months. The presence of soft drusen, drusenoid PED, AVL, thin DLS, and IHRF at the baseline visit was all associated with a significantly increased risk of cRORA at that location. Multivariable logistic regression revealed that IHRF (OR, 8.559; p < 0.001), drusenoid PED (OR, 7.148; p = 0.001), and a thin DLS (OR, 3.483; p = 0.021) were independent predictors of development of cRORA at that location.

CONCLUSIONS

IHRF, drusenoid PED, and thin DLS are all local risk factors for the development of cRORA at that same location. These findings would support the inclusion of these features within a more granular staging system defining specific steps in the progression from early AMD to atrophy.

Verteporfin Photodynamic Therapy for the Treatment of Chorioretinal Conditions: A Narrative Review

Photodynamic therapy (PDT) with verteporfin involves intravenous administration of a photosensitizer followed by its laser light activation at the target site to inhibit aberrant choroidal vascularization. This narrative review provides an overview of the role verteporfin PDT plays in the management of chorioretinal conditions. A PubMed literature review of all English-language articles published through October 19, 2023, was conducted to identify relevant references. Verteporfin PDT has been shown to be safe and effective for the treatment of patients with choroidal neovascularization (CNV) due to neovascular age-related macular degeneration and is often used in combination with a vascular endothelial growth factor (VEGF) inhibitor. Additionally, patients with polypoidal choroidal vasculopathy, a subtype of neovascular age-related macular degeneration, also benefit from verteporfin PDT combined with a VEGF inhibitor for improving visual acuity. Verteporfin PDT has also been effective in treating patients with peripapillary CNV, as well as eyes with CNV due to ocular histoplasmosis and pathologic myopia. Reduced dose and/or fluence PDT protocols have been effective in patients with central serous chorioretinopathy while reducing adverse effects. In eyes with choroidal hemangioma, tumor regression and visual outcomes have been improved with verteporfin PDT treatment. Photodynamic therapy with verteporfin continues to play an important role in the management of chorioretinal conditions.

Therapeutic targets for age-related macular degeneration: proteome-wide Mendelian randomization and colocalization analyses

Background

Currently, effective therapeutic drugs for age-related macular degeneration (AMD) are urgently needed, and it is crucial to explore new treatment targets. The proteome is indispensable for exploring disease targets, so we conducted a Mendelian randomization (MR) of the proteome to identify new targets for AMD and its related subtypes.

Methods

The plasma protein level data used in this study were obtained from two large-scale studies of protein quantitative trait loci (pQTL), comprising 35,559 and 54,219 samples, respectively. The expression quantitative trait loci (eQTL) data were sourced from eQTLGen and GTEx Version 8. The discovery set for AMD data and subtypes was derived from the FinnGen study, consisting of 9,721 AMD cases and 381,339 controls, 5,239 wet AMD cases and 273,920 controls, and 6,651 dry AMD cases and 272,504 controls. The replication set for AMD data was obtained from the study by Winkler TW et al., comprising 14,034 cases and 91,234 controls. Summary Mendelian randomization (SMR) analysis was employed to assess the association between QTL data and AMD and its subtypes, while colocalization analysis was performed to determine whether they share causal variants. Additionally, chemical exploration and molecular docking were utilized to validate potential drugs targeting the identified proteins.

Results

SMR and colocalization analysis jointly identified risk-associated proteins for AMD and its subtypes, including 5 proteins (WARS1, BRD2, IL20RB, TGFB1, TNFRSF10A) associated with AMD, 2 proteins (WARS1, IL20RB) associated with Dry-AMD, and 9 proteins (COL10A1, WARS1, VTN, SDF2, LBP, CD226, TGFB1, TNFRSF10A, CSF2) associated with Wet-AMD. The results revealed potential therapeutic chemicals, and molecular docking indicated a good binding between the chemicals and protein structures.

Conclusion

Proteome-wide MR have identified risk-associated proteins for AMD and its subtypes, suggesting that these proteins may serve as potential therapeutic targets worthy of further clinical investigation.

IGF2BP2 Maintains Retinal Pigment Epithelium Homeostasis by Stabilizing PAX6 and OTX2

Purpose

N6-methyladenosine (m6A) methylation is a chemical modification that occurs on RNA molecules, where the hydrogen atom of adenine (A) nucleotides is replaced by a methyl group, forming N6-methyladenosine. This modification is a dynamic and reversible process that plays a crucial role in regulating various biological processes, including RNA stability, transport, translation, and degradation. Currently, there is a lack of research on the role of m6A modifications in maintaining the characteristics of RPE cells. m6A readers play a crucial role in executing the functions of m6A modifications, which prompted our investigation into their regulatory roles in the RPE.

Methods

Phagocytosis assays, immunofluorescence staining, flow cytometry experiments, β-galactosidase staining, and RNA sequencing (RNA-seq) were conducted to assess the functional and cellular characteristics changes in retinal pigment epithelium (RPE) cells following short-hairpin RNA-mediated knockdown of insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2). RNA-seq and ultraviolet crosslinking immunoprecipitation with high-throughput sequencing (HITS-CLIP) were employed to identify the target genes regulated by IGF2BP2. adeno-associated virus (AAV) subretinal injection was performed in 6- to 8-week-old C57 mice to reduce IGF2BP2 expression in the RPE, and the impact of IGF2BP2 knockdown on mouse visual function was assessed using immunofluorescence, quantitative real-time PCR, optical coherence tomography, and electroretinography.

Results

IGF2BP2 was found to have a pronounced effect on RPE phagocytosis. Subsequent in-depth exploration revealed that IGF2BP2 modulates the mRNA stability of PAX6 and OTX2, and the loss of IGF2BP2 induces inflammatory and aging phenotypes in RPE cells. IGF2BP2 knockdown impaired RPE function, leading to retinal dysfunction in vivo.

Conclusions

Our data suggest a crucial role of IGF2BP2 as an m6A reader in maintaining RPE homeostasis by regulating the stability of PAX6 and OTX2, making it a potential target for preventing the occurrence of retinal diseases related to RPE malfunction.

A Sustainable Retinal Drug Co-Delivery for Boosting Therapeutic Efficacy in wAMD: Unveiling Multifaceted Evidence and Synergistic Mechanisms

Sustainable retinal codelivery poses significant challenges technically, although it is imperative for synergistic treatment of wet age-related macular degeneration (wAMD). Here, a microemulsion-doped hydrogel (Bor/PT-M@TRG) is engineered as an intravitreal depot composing of temperature-responsive hydrogel (TRG) and borneol-decorated paeoniflorin (PF) & tetramethylpyrazine (TMP)-coloaded microemulsions (Bor/PT-M). Bor/PT-M@TRG, functioning as the "ammunition depot", resides in the vitreous and continuously releases Bor/PT-M as the therapeutic "bullet", enabling deep penetration into the retina for 21 days. A single intravitreal injection of Bor/PT-M@TRG yields substantial reductions in choroidal neovascularization (CNV, a hallmark feature of wAMD) progression and mitigates oxidative stress-induced damage in vivo. Combinational PF&TMP regulates the "reactive oxygen species/nuclear factor erythroid-2-related factor 2/heme oxygenase-1" pathway and blocks the "hypoxia inducible factor-1α/vascular endothelial growth factor" signaling in retina, synergistically cutting off the loop of CNV formation. Utilizing fluorescence resonance energy transfer and liquid chromatography-mass spectrometry techniques, they present compelling multifaceted evidence of sustainable retinal codelivery spanning formulations, ARPE-19 cells, in vivo eye balls, and ex vivo section/retina-choroid complex cell levels. Such codelivery approach is elucidated as the key driving force behind the exceptional therapeutic outcomes of Bor/PT-M@TRG. These findings highlight the significance of sustainable retinal drug codelivery and rational combination for effective treatment of wAMD.

LXR/CD38 activation drives cholesterol-induced macrophage senescence and neurodegeneration via NAD+ depletion

Although dysregulated cholesterol metabolism predisposes aging tissues to inflammation and a plethora of diseases, the underlying molecular mechanism remains poorly defined. Here, we show that metabolic and genotoxic stresses, convergently acting through liver X nuclear receptor, upregulate CD38 to promote lysosomal cholesterol efflux, leading to nicotinamide adenine dinucleotide (NAD+) depletion in macrophages. Cholesterol-mediated NAD+ depletion induces macrophage senescence, promoting key features of age-related macular degeneration (AMD), including subretinal lipid deposition and neurodegeneration. NAD+ augmentation reverses cellular senescence and macrophage dysfunction, preventing the development of AMD phenotype. Genetic and pharmacological senolysis protect against the development of AMD and neurodegeneration. Subretinal administration of healthy macrophages promotes the clearance of senescent macrophages, reversing the AMD disease burden. Thus, NAD+ deficit induced by excess intracellular cholesterol is the converging mechanism of macrophage senescence and a causal process underlying age-related neurodegeneration.

Evaluation of a Digital Amsler Grid (PocDoc) for Macular Disease Screening: A Comparative Analysis with the Conventional Method

INTRODUCTION

Macular diseases are major contributors to visual impairment and blindness worldwide. This study introduces PocDoc, a digital version of the conventional Amsler grid, aimed at enhancing the screening and monitoring of macular diseases. We conducted a comprehensive evaluation to compare the effectiveness of PocDoc against the conventional method.

METHODS

Our comparative analysis involved two distinct phases. Initially, we assessed the capability of both PocDoc and the conventional method in detecting central visual field abnormalities. This phase included a cohort of 72 healthy and 155 eyes affected by various conditions such as age-related macular degeneration (AMD), uveitis, polypoidal choroidal vasculopathy (PCV), and macular telangiectasia. We primarily focused on the area of compromise and observed the correlation between the results obtained from both methods, measuring their concordance using a correlation coefficient. In the second phase, we evaluated the accuracy of both methods in diagnosing AMD. This involved a group of 127 eyes, including 70 healthy and 57 AMD-affected eyes. We determined the sensitivity, specificity, and overall accuracy of each method in diagnosing AMD.

RESULTS

In the initial phase, both PocDoc and the conventional Amsler grid demonstrated a high correlation in detecting central visual field defects across various macular diseases (correlation coefficient > 0.9). In the second phase, focused on AMD diagnosis, PocDoc showed a sensitivity of 50%, specificity of 100%, and an overall accuracy of 78%. Comparatively, the conventional method exhibited a sensitivity of 49%, specificity of 100%, and accuracy of 77%.

CONCLUSION

PocDoc's digital Amsler grid exhibits comparable effectiveness to the conventional method in both detecting visual field abnormalities across a range of macular diseases and specifically in the diagnosis of AMD. The high correlation in results, combined with the digital advantages of PocDoc, such as ease of use and potential for telemedicine applications, suggests its viability as a valuable tool in the screening and monitoring of macular diseases.

Complement regulation in the eye: implications for age-related macular degeneration

Careful regulation of the complement system is critical for enabling complement proteins to titrate immune defense while also preventing collateral tissue damage from poorly controlled inflammation. In the eye, this balance between complement activity and inhibition is crucial, as a low level of basal complement activity is necessary to support ocular immune privilege, a prerequisite for maintaining vision. Dysregulated complement activation contributes to parainflammation, a low level of inflammation triggered by cellular damage that functions to reestablish homeostasis, or outright inflammation that disrupts the visual axis. Complement dysregulation has been implicated in many ocular diseases, including glaucoma, diabetic retinopathy, and age-related macular degeneration (AMD). In the last two decades, complement activity has been the focus of intense investigation in AMD pathogenesis, leading to the development of novel therapeutics for the treatment of atrophic AMD. This Review outlines recent advances and challenges, highlighting therapeutic approaches that have advanced to clinical trials, as well as providing a general overview of the complement system in the posterior segment of the eye and selected ocular diseases.

Association between ambient air pollution and age-related macular degeneration: a meta-analysis

BACKGROUND

Several epidemiological studies have investigated the association between ambient air pollution and age-related macular degeneration (AMD). However, a consensus has not yet been reached. Our meta-analysis aimed to clarify this association.

METHODS

Databases, including PubMed, EMBASE, and Web of Science, were searched for relevant studies from 01 January 2000 to 30 January 2024. English-language, peer-reviewed studies using cross-sectional, prospective, or retrospective cohorts and case-control studies exploring this relationship were included. Two authors independently extracted data and assessed study quality. A random-effects model was used to calculate pooled covariate-adjusted odds ratios. Heterogeneity across studies was also tested.

RESULTS

We identified 358 relevant studies, of which eight were included in the meta-analysis. Four studies evaluated the association between particulate matter less than 2.5 μm in diameter (PM2.5) and AMD, and three studies explored the relationship between nitrogen dioxide (NO2) or ozone (O3) and AMD. The pooled odds ratios were 1.16 (95% confidence interval [CI]: 1.11-1.21), 1.17 (95% CI: 1.09-1.25), and 1.06 (95% CI: 1.05-1.07), respectively.

CONCLUSION

Current evidence suggests a concomitant positive but not causal relationship between PM2.5, NO2, or O3 and AMD risk.

Incidence and risk factors of age-related macular degeneration in patients with Parkinson's disease: a population-based study

Background and objective

The association between age-related macular degeneration (AMD) and Parkinson' disease (PD) remains unclear. The aim of the present study was to assess the incidence of AMD in patients with PD, elucidate differences by age and sex, and investigate potential risk factors for AMD.

Methods

Data were extracted from the Korean National Health Insurance System database, which covers 97% of the Korean population (2002 through 2019). We calculated the incidence of newly diagnosed AMD in patients with PD and used Cox proportional-hazards models to estimate risk factors for AMD, presenting adjusted hazard ratios (aHR) with 95% confidence intervals (CI).

Results

Of 172,726 patients with PD, 15,800 were newly diagnosed with AMD during the follow-up, including 5,624 men and 10,176 women. The overall incidence of AMD in patients with PD was 13.59 per 1,000 person-years. Stratified by age group and sex, the incidence was higher in women aged 40-69, and conversely higher in men aged 70-89. Risk of AMD was high in older age groups (aHR = 4.36, 95% CI: 3.74-5.09 in the 70 s), female sex (aHR = 1.07, 95% CI: 1.04-1.11), patients with diabetes mellitus (DM) (aHR = 1.14, 95% CI: 1.10-1.18), and patients with hyperlipidemia (aHR = 1.17, 95% CI: 1.13-1.21).

Conclusion

Our findings suggest that the AMD incidence is higher in patients with PD than in the general population, with varying patterns of sex differences across age groups. Particularly, old age, female sex, presence of DM, and hyperlipidemia are potential risk factors. Therefore, clinicians should pay greater attention to AMD in patients with PD.

Cell-specific Systemic Immune Signatures Associated with Treatment Burden in Neovascular Age-related Macular Degeneration

Purpose

Choroidal neovascularization (CNV) accounts for the majority of severe vision loss in neovascular age-related macular degeneration (AMD). Despite therapies that target VEGF, patients are often under-responsive, require frequent eye injections to control disease, and eventually lose some vision despite chronic therapy implicating a multifactorial etiology in treatment response. Genetic studies implicate systemic immunity in AMD and systemic immune cells accumulate within CNV lesions, yet a role for these cells in anti-VEGF response remains undetermined. The purpose of this study was to identify transcriptional signatures of circulating immune cells that are associated with high anti-VEGF treatment burden.

Design

Experimental pilot study.

Participants

Patients with neovascular AMD seen at Washington University School of Medicine in St. Louis and BJC Health System.

Methods

We profiled by single cell RNA sequencing the peripheral blood mononuclear cells of 27 treatment-experienced patients with wet AMD. We stratified this cohort into 2 groups with low and high treatment burden (≤ 5 or ≥ 6 injections in the past 12 months, respectively).

Main Outcome Measures

Identification of immune cells associated with high treatment burden.

Results

Gene expression signature of CD16+ monocytes may be associated with high treatment burden.

Conclusions

These studies delineate potential signatures of circulating immune cells that may be associated with high treatment burden in neovascular AMD, potentially informing the development of diagnostic predictors of anti-VEGF response and new precision medicine-based approaches to complement anti-VEGF therapies.

Financial Disclosures

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Puerarin Attenuates Iron Overload-Induced Ferroptosis in Retina through a Nrf2-Mediated Mechanism

SCOPE

Age-related increases in retinal iron are involved in the development of retinal degeneration. The recently discovered iron-dependent mechanism of cell death known as ferroptosis has been linked to a wide range of pathologies. However, its role in iron overload-induced retinal degeneration is still uncertain. Puerarin has been associated with retinal protection. The purpose of this research is to determine how puerarin prevents retinal ferroptosis under iron overload conditions.

METHODS AND RESULTS

Models of iron overload in Kunming mice, 661W cell, and ARPE-19 cell are established. Increased iron deposition significantly worsens retinal pathology, decreases cell viability, and induces ferroptotic changes. Puerarin mitigates iron overload-induced ferroptosis by decreasing excessive iron through the regulation of iron handling proteins and lowering lipid peroxidation through the inhibition of cyclooxygenase 2 expression and activation of the nuclear factor-E2-related factor 2 (Nrf2) signaling pathway and downstream ferroptosis-related proteins (solute carrier family 7 member 11, glutathione peroxidase 4 and heme oxygenase-1). The protective effect of puerarin on ferroptosis is diminished by the Nrf2-specific inhibitor ML385.

CONCLUSION

These findings suggest targeting ferroptosis may be a novel strategy for the management of retinal degeneration. Puerarin may exert some of its ocular benefits by attenuating ferroptosis.

Analyzing shifts in age-related macular degeneration research trends since 2014: A bibliometric study with triple-map Sankey diagrams (TMSD)

BACKGROUND

Age-related macular degeneration (AMD) is the primary cause of vision impairment in older adults, especially in developed countries. While many articles on AMD exist in the literature, none specifically delve into the trends based on document categories. While bibliometric studies typically use dual-map overlays to highlight new trends, these can become congested and unclear with standard formats (e.g., in CiteSpace software). In this study, we introduce a unique triple-map Sankey diagram (TMSD) to assess the evolution of AMD research. Our objective is to understand the nuances of AMD articles and show the effectiveness of TMSD in determining whether AMD research trends have shifted over the past decade.

METHODS

We collected 7465 articles and review pieces related to AMD written by ophthalmologists from the Web of Science core collection, accumulating article metadata from 2014 onward. To delve into the characteristics of these AMD articles, we employed various visualization methods, with a special focus on TMSD to track research evolution. We adopted the descriptive, diagnostic, predictive, and prescriptive analytics (DDPP) model, complemented by the follower-leading clustering algorithm (FLCA) for clustering analysis. This synergistic approach proved efficient in identifying and showcasing research focal points and budding trends using network charts within the DDPP framework.

RESULTS

Our findings indicate that: in countries, institutes, years, authors, and journals, the dominant entities were the United States, the University of Bonn in Germany, the year 2021, Dr Jae Hui Kim from South Korea, and the journal "Retina"; in accordance with the TMSD, AMD research trends have not changed significantly since 2014, as the top 4 categories for 3 citing, active, and cited articles have not changed, in sequence (Ophthalmology, Science & Technology - Other Topics, General & Internal Medicine, Pharmacology & Pharmacy).

CONCLUSION

The introduced TMSD, which incorporates the FLCA algorithm and features in 3 columns-cited, active, and citing research categories-offers readers clearer insights into research developments compared to the traditional dual-map overlays from CiteSpace software. Such tools are especially valuable for streamlining the visualization of the intricate data often seen in bibliometric studies.

Targeting cell-type-specific, choroid-peripheral immune signaling to treat age-related macular degeneration

Age-related macular degeneration (AMD) is a leading cause of blindness featuring pathogenic neovascularization of the choroidal vasculature (CNV). Although systemic immunity plays a role in AMD, the ocular signals that recruit and activate immune cells remain poorly defined. Using single-cell RNA sequencing, we prospectively profile peripheral blood mononuclear cells from 65 individuals including AMD and controls, which we integrate with existing choroid data. We generate a network of choroid-peripheral immune interactions dysregulated in AMD, including known AMD-relevant gene vascular endothelial growth factor (VEGF) receptor 2. Additionally, we find CYR61 is upregulated in choroidal veins and may signal to circulating monocytes. In mice, we validate that CYR61 is abundant in endothelial cells within CNV lesions neighboring monocyte-derived macrophages. Mechanistically, CYR61 activates macrophage anti-angiogenic gene expression, and ocular Cyr61 knockdown increases murine CNV size, indicating CYR61 inhibits CNV. This study highlights the potential of multi-tissue human datasets to identify disease-relevant and potentially therapeutically modifiable targets.

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.

Advancements in the treatment of geographic atrophy: focus on pegcetacoplan in age-related macular degeneration

Geographic atrophy (GA) is a progressive form of age-related macular degeneration characterized by the degeneration of retinal pigment epithelial cells and photoreceptor death. The dysregulation of the complement cascade has been implicated in GA progression. This review provides a comprehensive overview of the pathophysiology of age-related macular degeneration and GA, discusses current therapeutic options, and focuses on the recent breakthrough drug, pegcetacoplan (SYFOVRE). Pegcetacoplan is a complement inhibitor that selectively targets the C3 complement protein, effectively modulating complement activation. Clinical trials, including the OAKS and DERBY studies, have demonstrated the efficacy of SYFOVRE in reducing the growth of GA lesions compared to placebo. The FDA approval of SYFOVRE as the first and only definitive therapy for GA marks a significant milestone in the management of this debilitating condition. The review also explores potential future treatment strategies, including immune-modulating agents and ocular gene therapy. While SYFOVRE offers new hope for GA patients, further research is needed to evaluate its long-term benefits, safety profile, and optimal treatment regimens.

Oxidative stress in the eye and its role in the pathophysiology of ocular diseases

Oxidative stress occurs through an imbalance between the generation of reactive oxygen species (ROS) and the antioxidant defense mechanisms of cells. The eye is particularly exposed to oxidative stress because of its permanent exposure to light and due to several structures having high metabolic activities. The anterior part of the eye is highly exposed to ultraviolet (UV) radiation and possesses a complex antioxidant defense system to protect the retina from UV radiation. The posterior part of the eye exhibits high metabolic rates and oxygen consumption leading subsequently to a high production rate of ROS. Furthermore, inflammation, aging, genetic factors, and environmental pollution, are all elements promoting ROS generation and impairing antioxidant defense mechanisms and thereby representing risk factors leading to oxidative stress. An abnormal redox status was shown to be involved in the pathophysiology of various ocular diseases in the anterior and posterior segment of the eye. In this review, we aim to summarize the mechanisms of oxidative stress in ocular diseases to provide an updated understanding on the pathogenesis of common diseases affecting the ocular surface, the lens, the retina, and the optic nerve. Moreover, we discuss potential therapeutic approaches aimed at reducing oxidative stress in this context.

Activation of Lysosomal Function Ameliorates Amyloid-β-Induced Tight Junction Disruption in the Retinal Pigment Epithelium

Accumulation of pathogenic amyloid-β disrupts the tight junction of retinal pigment epithelium (RPE), one of its senescence-like structural alterations. In the clearance of amyloid-β, the autophagy-lysosome pathway plays the crucial role. In this context, mammalian target of rapamycin (mTOR) inhibits the process of autophagy and lysosomal degradation, acting as a potential therapeutic target for age-associated disorders. However, efficacy of targeting mTOR to treat age-related macular degeneration remains largely elusive. Here, we validated the therapeutic efficacy of the mTOR inhibitors, Torin and PP242, in clearing amyloid-β by inducing the autophagy-lysosome pathway in a mouse model with pathogenic amyloid-β with tight junction disruption of RPE, which is evident in dry age-related macular degeneration. High concentration of amyloid-β oligomers induced autophagy-lysosome pathway impairment accompanied by the accumulation of p62 and decreased lysosomal activity in RPE cells. However, Torin and PP242 treatment restored the lysosomal activity via activation of LAMP2 and facilitated the clearance of amyloid-β in vitro and in vivo. Furthermore, clearance of amyloid-β by Torin and PP242 ameliorated the tight junction disruption of RPE in vivo. Overall, our findings suggest mTOR inhibition as a new therapeutic strategy for the restoration of tight junctions in age-related macular degeneration.

Acute Kidney Injury from Intravitreal Anti-vascular Endothelial Growth Factor Drugs: A Systematic Review and Meta-analysis of Randomized Controlled Trials

BACKGROUND

Several observational studies have reported acute kidney injury from intravitreal anti-vascular endothelial growth factor (anti-VEGF) drugs for retinal diseases. However, systematic reviews and meta-analyses of randomized controlled trials on this critical topic are scant.

OBJECTIVE

To evaluate acute kidney injury risk associated with intravitreal anti-VEGF drugs in patients with retinal diseases.

METHODS

We searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials on 12 July, 2023, and included randomized controlled trials reporting acute kidney injury between anti-VEGF drugs (e.g., aflibercept, bevacizumab, brolucizumab, and ranibizumab) and controls for retinal diseases (e.g., age-related macular degeneration, polypoidal choroidal vasculopathy, diabetic retinopathy/diabetic macular edema, retinal vein occlusion, and myopic choroidal neovascularization). Data were synthesized by a fixed-effects model for pooling odds ratios (ORs) using the Peto method.

RESULTS

We included 13 randomized controlled trials (four and nine trials for aflibercept and ranibizumab, respectively) with a total of 4282 participants. The meta-analysis indicated intravitreal anti-VEGF drugs did not increase the acute kidney injury risk, compared with controls (odds ratio [OR]: 1.00, 95% confidence interval [CI] 0.49-2.04, I2: 0%), and no differences in the acute kidney injury risk were observed between different anti-VEGF drugs (OR: 1.10, 95% CI 0.27-4.43, I2: 0% for aflibercept; OR: 0.97, 95% CI 0.42-2.22, I2: 0% for ranibizumab) and between different retinal diseases (OR: 4.61, 95% CI 0.07-284.13, I2: not applicable for age-related macular degeneration; OR: 0.90, 95% CI 0.42-1.93, I2: 0% for diabetic retinopathy/diabetic macular edema; OR: 1.57, 95% CI 0.16-15.88, I2: 0% for retinal vein occlusion).

CONCLUSIONS

Intravitreal anti-VEGF drugs were not associated with an acute kidney injury risk, regardless of which anti-VEGF drugs (aflibercept or ranibizumab) or retinal diseases (age-related macular degeneration, diabetic retinopathy/diabetic macular edema, or retinal vein occlusion) were involved.

SYSTEMATIC REVIEW PROTOCOL REGISTRATION

PROSPERO CRD42021267854.

The evolving role of cholesteryl ester transfer protein inhibition beyond cardiovascular disease

The main role of cholesteryl ester transfer protein (CETP) is the transfer of cholesteryl esters and triglycerides between high-density lipoprotein (HDL) particles and triglyceride-rich lipoprotein and low-density lipoprotein (LDL) particles. There is a long history of investigations regarding the inhibition of CETP as a target for reducing major adverse cardiovascular events. Initially, the potential effect on cardiovascular events of CETP inhibitors was hypothesized to be mediated by their ability to increase HDL cholesterol, but, based on evidence from anacetrapib and the newest CETP inhibitor, obicetrapib, it is now understood to be primarily due to reducing LDL cholesterol and apolipoprotein B. Nevertheless, evidence is also mounting that other roles of HDL, including its promotion of cholesterol efflux, as well as its apolipoprotein composition and anti-inflammatory, anti-oxidative, and anti-diabetic properties, may play important roles in several diseases beyond cardiovascular disease, including, but not limited to, Alzheimer's disease, diabetes, and sepsis. Furthermore, although Mendelian randomization analyses suggested that higher HDL cholesterol is associated with increased risk of age-related macular degeneration (AMD), excess risk of AMD was absent in all CETP inhibitor randomized controlled trial data comprising over 70,000 patients. In fact, certain HDL subclasses may, in contrast, be beneficial for treating the retinal cholesterol accumulation that occurs with AMD. This review describes the latest biological evidence regarding the relationship between HDL and CETP inhibition for Alzheimer's disease, type 2 diabetes mellitus, sepsis, and AMD.

Losing, preserving, and restoring vision from neurodegeneration in the eye

The retina is a part of the brain that sits at the back of the eye, looking out onto the world. The first neurons of the retina are the rod and cone photoreceptors, which convert changes in photon flux into electrical signals that are the basis of vision. Rods and cones are frequent targets of heritable neurodegenerative diseases that cause visual impairment, including blindness, in millions of people worldwide. This review summarizes the diverse genetic causes of inherited retinal degenerations (IRDs) and their convergence onto common pathogenic mechanisms of vision loss. Currently, there are few effective treatments for IRDs, but recent advances in disparate areas of biology and technology (e.g., genome editing, viral engineering, 3D organoids, optogenetics, semiconductor arrays) discussed here enable promising efforts to preserve and restore vision in IRD patients with implications for neurodegeneration in less approachable brain areas.

An insight on ophthalmic drug delivery systems: Focus on polymeric biomaterials-based carriers

Presently, different types of eye diseases, such as glaucoma, myopia, infection, and dry eyes are treated with topical eye drops. However, due to ocular surface barriers, eye drops require multiple administrations, which may cause several risks, thereby necessitating additional strategies. Some of the key characteristics of an ideal ocular drug delivery system are as follows: (a) good penetration into cornea, (b) high drug retention in the ocular tissues, (c) targetability to the desired regions of the eye, and (d) good bioavailability. It is worthy to note that the corneal epithelial tight junctions hinder the permeation of therapeutics through the cornea. Therefore, it is necessary to design nanocarriers that can overcome these barriers and enhance drug penetration into the inner parts of the eye. Moreover, intelligent multifunctional nanocarriers can be designed to include cavities, which may help encapsulate sufficient amount of the drug. In addition, nanocarriers can be modified with the targeting moieties. Different types of nanocarriers have been developed for ocular drug delivery applications, including emulsions, liposomes, micelles, and nanoparticles. However, these formulations may be rapidly cleared from the eye. The therapeutic use of the nanoparticles (NPs) is also hindered by the non-specific adsorption of proteins on NPs, which may limit their interaction with the cellular moieties or other targeted biological factors. Functional drug delivery systems (DDS), which can offer targeted ocular drug delivery while avoiding the non-specific protein adsorption could exhibit great potential. This could be further realized by the on-demand DDS, which can respond to the stimuli in a spatio-temporal fashion. The cell-mediated DDS offer another valuable platform for ophthalmological drug delivery.

Diurnal variation of optical coherence tomography-based macular fluid in exudative age-related macular degeneration

BACKGROUND

Significant diurnal fluctuation of optical coherence tomography (OCT)-based macular fluid occurs in patients with several macular conditions including diabetic macular edema (DME) and cystoid macular edema due to retinal venous occlusion (RVO). OCT imaging and analysis of macular fluid status plays a central role in clinical management of exudative age-related macular degeneration (eAMD), however diurnal variation of eAMD OCT findings has not yet been formally studied. Herein, we investigate whether clinically meaningful fluctuation of OCT-based macular fluid occurs in patients with eAMD.

METHODS

Prospective observational study. Patients with eAMD and intra- and/or sub-retinal fluid on early AM OCT were enrolled to receive two consecutive OCT scans at least four hours later. Retinal layers were manually segmented on all OCT rasters and AM-to-PM and PM-to-PM image pairs were analyzed for total retinal and neurosensory retinal volume changes within the central 1 and 3 mm ETDRS subfields. Finally, two masked retinal specialists analyzed all OCT image pairs for qualitative differences that may impact clinical management.

RESULTS

21 patients with eAMD and fluid on OCT were recruited between January 2020 and November 2021. There was no mean difference between AM and PM central 3 mm total retinal volume (p = 0.56), central 3 mm neurosensory retinal volume (p = 0.25), central 1 mm total retinal mean thickness (p = 0.96), or central 1 mm neurosensory retinal mean thickness (p = 0.63), nor were any differences identified in PM-to-PM control comparisons. Qualitative analysis by two masked experts identified no clinically significant differences between any AM-to-PM OCT image pairs.

CONCLUSIONS

No significant diurnal variation in OCT-based macular fluid or thickness was identified in patients with eAMD, either quantitatively or qualitatively.

A new era in posterior segment ocular drug delivery: Translation of systemic, cell-targeted, dendrimer-based therapies

Vision impairment and loss due to posterior segment ocular disorders, including age-related macular degeneration and diabetic retinopathy, are a rapidly growing cause of disability globally. Current treatments consist primarily of intravitreal injections aimed at preventing disease progression and characterized by high cost and repeated clinic visits. Nanotechnology provides a promising platform for drug delivery to the eye, with potential to overcome anatomical and physiological barriers to provide safe, effective, and sustained treatment modalities. However, there are few nanomedicines approved for posterior segment disorders, and fewer that target specific cells or that are compatible with systemic administration. Targeting cell types that mediate these disorders via systemic administration may unlock transformative opportunities for nanomedicine and significantly improve patient access, acceptability, and outcomes. We highlight the development of hydroxyl polyamidoamine dendrimer-based therapeutics that demonstrate ligand-free cell targeting via systemic administration and are under clinical investigation for treatment of wet age-related macular degeneration.

Cytokine profiles in the aqueous humor following brolucizumab administration for exudative age-related macular degeneration

PURPOSE

To identify the inflammatory cytokine profile in the aqueous humor (AH) of patients with intraocular inflammation (IOI) after intravitreal administration of brolucizumab (IVBr) for neovascular age-related macular degeneration.

METHODS

Eight eyes from seven patients with IOI after initial IVBr (IVBrIOI +) were enrolled. Sixteen eyes from 16 patients without IOI after IVBr (IVBrIOI -) and aflibercept (IVA) were used as controls. AH samples were analyzed using a multiplex immunoassay.

RESULTS

C-C motif chemokine ligand (CCL)2, C-X-C motif chemokine ligand (CXCL)1, CXCL10, CXCL13, interleukin (IL)-6, IL-8, IL-10, matrix metalloproteinase (MMP)-1, MMP-9, granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), intercellular adhesion molecule (ICAM)-1, E-selectin, and P-selectin levels were significantly higher in IVBrIOI + than in IVBrIOI - and IVA. Vascular endothelial growth factor (VEGF) was significantly lower in IVBrIOI - compared to that in IVBrIOI + and IVA. In the IVBrIOI + group, there were significant correlations between CCL2, CXCL1, IL-6, IL-8, IL-10, G-CSF, GM-CSF, ICAM-1, and E-selectin, which also exhibited significant correlations in the IVBrIOI - group.

CONCLUSION

The number of inflammatory cytokines increases during IOI, which is associated with type IV hypersensitivity and vascular inflammation. Some cytokines exhibit correlations even in non-inflamed eyes, indicating a subclinical response to IVBr.

Randomized Trial of Biosimilar XSB-001 versus Reference Ranibizumab in Patients with Neovascular Age-Related Macular Degeneration

OBJECTIVE

To evaluate the efficacy, safety, and immunogenicity of a ranibizumab biosimilar candidate (XSB-001) versus reference product (Lucentis) for neovascular age-related macular degeneration (nAMD).

DESIGN

Phase III, multicenter, randomized, double-masked, parallel-group study.

PARTICIPANTS

Patients with nAMD.

METHODS

Eligible patients were randomized (1:1) to receive intravitreal injections of XSB-001 or reference ranibizumab (0.5 mg [0.05 ml]) in the study eye once every 4 weeks for 52 weeks. Efficacy and safety assessments continued through 52 weeks of treatment.

MAIN OUTCOME MEASURES

Primary end point was change from baseline in best-corrected visual acuity (BCVA) by ETDRS letters at week 8. Biosimilarity was concluded if the 2-sided 90% confidence interval (CI) (United States) or 95% CI (rest of world) for the difference in least-squares (LS) mean change in BCVA at week 8 between treatment groups was within the predefined equivalence margin of ± 3.5 letters.

RESULTS

In total, 582 patients (n = 292 XSB-001, n = 290 reference ranibizumab) were randomized. Mean age was 74.1 years, most patients (85.2%) were White, and 55.8% were women. Mean BCVA score at baseline was 61.7 and 61.5 ETDRS letters in the XSB-001 and reference ranibizumab groups, respectively. At week 8, the LS mean (standard error [SE]) change in BCVA from baseline was 4.6 (0.5) ETDRS letters in the XSB-001 group and 6.4 (0.5) letters in the reference ranibizumab group (LS mean [SE] treatment difference: -1.8 [0.7] ETDRS letters; 90% CI, -2.9 to -0.7; 95% CI, -3.1 to -0.5). The 90% CI and 95% CI for LS mean difference in change from baseline were within the predefined equivalence margin. At week 52, LS mean (SE) change in BCVA was 6.4 (0.8) and 7.8 (0.8) letters, respectively (LS mean [SE] treatment difference, -1.5 [1.1] ETDRS letters; 90% CI, -3.3 to 0.4; 95% CI, -3.6 to 0.7). There were no clinically meaningful differences between treatments in anatomical, safety, or immunogenicity end points through week 52.

CONCLUSIONS

XSB-001 demonstrated biosimilarity to reference ranibizumab in patients with nAMD. Treatment with XSB-001 for 52 weeks was generally safe and well tolerated, with a safety profile similar to the reference product.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Loss of stearoyl-CoA desaturase 2 disrupts inflammatory response in macrophages

Macrophages are innate immune cells that patrol tissues and are the first responders to detect infection. They orchestrate the host immune response in eliminating invading pathogens and the subsequent transition from inflammation to tissue repair. Macrophage dysfunction contributes to age-related pathologies, including low-grade inflammation in advanced age that is termed "inflammaging." Our laboratory has previously identified that macrophage expression of a fatty acid desaturase, stearoyl-CoA desaturase 2 (SCD2), declines with age. Herein, we delineate the precise cellular effects of SCD2 deficiency in murine macrophages. We found that deletion of Scd2 from macrophages dysregulated basal and bacterial lipopolysaccharide (LPS)-stimulated transcription of numerous inflammation-associated genes. Specifically, deletion of Scd2 from macrophages decreased basal and LPS-induced expression of Il1b transcript that corresponded to decreased production of precursor IL1B protein and release of mature IL1B. Furthermore, we identified disruptions in autophagy and depletion of unsaturated cardiolipins in SCD2-deficient macrophages. To assess the functional relevance of SCD2 in the macrophage response to infection, we challenged SCD2-deficient macrophages with uropathogenic Escherichia coli and found that there was impaired clearance of intracellular bacteria. This increased burden of intracellular bacteria was accompanied by increased release of pro-inflammatory cytokines IL6 and TNF but decreased IL1B. Taken together, these results indicate that macrophage expression of Scd2 is necessary for maintaining the macrophage response to inflammatory stimuli. This link between fatty acid metabolism and fundamental macrophage effector functions may potentially be relevant to diverse age-related pathologies. IMPORTANCE Macrophages are immune cells that respond to infection, but their dysfunction is implicated in many age-related diseases. Recent evidence showed that macrophage expression of a fatty acid enzyme, stearoyl-CoA desaturase 2, declines in aged organisms. In this work, we characterize the effects when stearoyl-CoA desaturase 2 is deficient in macrophages. We identify aspects of the macrophage inflammatory response to infection that may be affected when expression of a key fatty acid enzyme is decreased, and these findings may provide cellular insight into how macrophages contribute to age-related diseases.

Characterization and contribution of RPE senescence to Age-related macular degeneration in Tnfrsf10 knock out mice

Background

Retinal pigment epithelial cells (RPE) play vital role in the pathogenesis of age-related macular degeneration (AMD). Our laboratory has shown that RPE cellular senescence contributed to the pathophysiology of experimental AMD, and SASP members are involved in this process. Recently, we presented confirmatory evidence to earlier GWAS studies that dysregulation of tumor necrosis factor receptor superfamily 10A (TNFRSF10A) dysregulation leads to AMD development and is linked to RPE dysfunction. This study aims to investigate the contribution of RPE senescence to AMD pathophysiology using TNFRSF10A silenced human RPE (hRPE) cells and Tnfrsf10 KO mice.

Methods

Sub-confluent primary hRPE cells and TNFRSF10A silenced hRPE were exposed to stress-induced premature senescence with H2O2 (500 μM, 48h), and senescence-associated markers (βgal, p16, and p21) were analyzed by RT-PCR and WB analysis. The effect of H2O2-induced senescence in non-silenced and silenced hRPE on OXPHOS and glycolysis was determined using Seahorse XF96 analyzer. Male C57BL/6J Tnfrsf10 KO ( Tnfrsf10 -/- ) mice were used to study the regulation of senescence by TNFRSF10A in vivo . Expression of p16 and p21 in control and KO mice of varying ages were determined by RT-PCR, WB, and immunostaining analysis.

Results

The senescence-associated p16 and p21 showed a significant ( p < 0.01) upregulation with H2O2 induction at the gene (1.8- and 3-fold) and protein (3.2- and 4-fold) levels in hRPE cells. The protein expression of p16 and p21 was further significantly increased by co-treatment with siRNA ( p < 0.05 vs. H2O2). Mitochondrial oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) (pmol/min/total DNA) increased with senescence induction by H2O2 for 48h in control RPE, and knockdown of TNFRSF10A caused a further increase in OCR and ECAR. In addition, co-treatment with PKC activator significantly improved all parameters. Similarly, in vivo studies showed upregulation of p16 and p21 by RT-PCR, WB, and immunostaining analysis in RPE/choroid of Tnfrsf10 KO mice. When subjected to examination across distinct age groups, namely young (1-3 months), middle (6-9 months), and old (12-15 months) mice, a discernible age-related elevation in the expression of p16 and p21 was observed.

Conclusions

Our findings suggest that TNRSF10A is a regulator of regulates in RPE senescence. Further work on elucidating pathways of senescence will facilitate the development of new therapeutic targets for AMD.

SEVERE VISUAL LOSS DURING ANTI-VEGF INTRAVITREAL INJECTIONS IN NEOVASCULAR AGE-RELATED MACULAR DEGENERATION: TIMING, PROGNOSIS, AND OPTICAL COHERENCE TOMOGRAPHY FINDINGS

PURPOSE

Intravitreal injection (IVI) of anti-vascular endothelial growth factor (VEGF) is the standard of care for neovascular age-related macular degeneration (nAMD). However, a small subgroup of patients still experience severe visual impairment, which may be related to the number of IVI administered.

METHODS

This retrospective observational study analyzed data from patients with sudden severe visual decline (≥15 Early Treatment Diabetic Retinopathy Study [ETDRS] letters loss between two consecutive IVIs) during anti-VEGF treatment for nAMD. Best-corrected visual acuity examination, optical coherence tomography (OCT), and OCT angiography (OCTA) were performed before every IVI and central macular thickness (CMT) and drug injected were collected.

RESULTS

1,019 eyes received anti-VEGF IVI for nAMD from December 2017 to March 2021. Severe VA loss occurred in 15.1% after a median of 6 (range 1-38) IVI. Ranibizumab was injected in 52.8% and aflibercept in 31.9% of cases. Functional recovery after 3 months was significant, without further improvement at 6 months. Visual prognosis relative to the percentage of CMT change showed better visual outcome in eyes with no substantial change in CMT compared with an increase of >20% or a decrease of >5%.

CONCLUSION

In this first real-life study exploring severe VA loss during anti-VEGF treatment in patients with nAMD, it was found that it was not unusual for a ≥15 ETDRS letters loss to occur between two consecutive IVIs, often within 9 months of diagnosis and 2 months after the last IVI. Close follow-up and a proactive regimen should be preferred, at least in the first year.

Alterations in Faecal and Serum Metabolic Profiles in Patients with Neovascular Age-Related Macular Degeneration

Neovascular age-related macular degeneration (nAMD) is a common and multifactorial disease in the elderly that may lead to irreversible vision loss; yet the pathogenesis of AMD remains unclear. In this study, nontargeted metabolomics profiling using ultra-performance liquid chromatography coupled with Q-Exactive Orbitrap mass spectrometry was applied to discover the metabolic feature differences in both faeces and serum samples between Chinese nonobese subjects with and without nAMD. In faecal samples, a total of 18 metabolites were significantly altered in nAMD patients, and metabolic dysregulations were prominently involved in glycerolipid metabolism and nicotinate and nicotinamide metabolism. In serum samples, a total of 29 differential metabolites were founded, involved in caffeine metabolism, biosynthesis of unsaturated fatty acids, and purine metabolism. Two faecal metabolites (palmitoyl ethanolamide and uridine) and three serum metabolites (4-hydroxybenzoic acid, adrenic acid, and palmitic acid) were selected as potential biomarkers for nAMD. Additionally, the significant correlations among dysregulated neuroprotective, antineuroinflammatory, or fatty acid metabolites in faecal and serum and IM dysbiosis were found. This comprehensive metabolomics study of faeces and serum samples showed that alterations in IM-mediated neuroprotective metabolites may be involved in the pathophysiology of AMD, offering IM-based nutritional therapeutic targets for nAMD.

Visual Outcomes of Anti-VEGF Treatment on Neovascular Age-Related Macular Degeneration: A Real-World Population-Based Cohort Study

Neovascular age-related macular degeneration (nAMD) leads to visual impairment if not treated promptly. Intravitreal anti-VEGF drugs have revolutionized nAMD treatment in the past two decades. We evaluated the visual outcomes of anti-VEGF treatment in nAMD. A real-life population-based cohort study. The data included parameters for age, sex, age at diagnosis, laterality, chronicity, symptoms, visual outcomes, lens status, and history of intravitreal injections. A total of 1088 eyes (827 patients) with nAMD were included. Visual acuity was stable or improved in 984 eyes (90%) after an average of 36 ± 25 months of follow-up. Bevacizumab was the first-line drug in 1083 (99.5%) eyes. Vision improved ≥15 ETDRS letters in 377 (35%), >5 ETDRS letters in 309 (28%), and was stable (±5 ETDRS letters) in 298 (27%) eyes after anti-VEGF treatment. The loss of 5 ≤ 15 ETDRS letters in 44 (4%) eyes and ≥15 ETDRS letters in 60 (6%) eyes was noted. At the diagnosis of nAMD, 110 out of 827 patients (13%) fulfilled the criteria for visual impairment, whereas 179 patients (22%) were visually impaired after the follow-up. Improvement or stabilization in vision was noted in 90% of the anti-VEGF-treated eyes with nAMD. In addition, anti-VEGF agents are crucial in diminishing nAMD-related visual impairment.

Inhibiting HIF-1 signaling alleviates HTRA1-induced RPE senescence in retinal degeneration

BACKGROUND

Age-related macular degeneration (AMD), characterized by the degeneration of retinal pigment epithelium (RPE) and photoreceptors, is the leading cause of irreversible vision impairment among the elderly. RPE senescence is an important contributor to AMD and has become a potential target for AMD therapy. HTRA1 is one of the most significant susceptibility genes in AMD, however, the correlation between HTRA1 and RPE senescence hasn't been investigated in the pathogenesis of AMD.

METHODS

Western blotting and immunohistochemistry were used to detect HTRA1 expression in WT and transgenic mice overexpressing human HTRA1 (hHTRA1-Tg mice). RT-qPCR was used to detect the SASP in hHTRA1-Tg mice and ARPE-19 cells infected with HTRA1. TEM, SA-β-gal was used to detect the mitochondria and senescence in RPE. Retinal degeneration of mice was investigated by fundus photography, FFA, SD-OCT and ERG. The RNA-Seq dataset of ARPE-19 cells treated with adv-HTRA1 versus adv-NC were analyzed. Mitochondrial respiration and glycolytic capacity in ARPE-19 cells were measured using OCR and ECAR. Hypoxia of ARPE-19 cells was detected using EF5 Hypoxia Detection Kit. KC7F2 was used to reduce the HIF1α expression both in vitro and in vivo.

RESULTS

In our study, we found that RPE senescence was facilitated in hHTRA1-Tg mice. And hHTRA1-Tg mice became more susceptible to NaIO₃ in the development of oxidative stress-induced retinal degeneration. Similarly, overexpression of HTRA1 in ARPE-19 cells accelerated cellular senescence. Our RNA-seq revealed an overlap between HTRA1-induced differentially expressed genes associated with aging and those involved in mitochondrial function and hypoxia response in ARPE-19 cells. HTRA1 overexpression in ARPE-19 cells impaired mitochondrial function and augmented glycolytic capacity. Importantly, upregulation of HTRA1 remarkably activated HIF-1 signaling, shown as promoting HIF1α expression which mainly located in the nucleus. HIF1α translation inhibitor KC7F2 significantly prevented HTRA1-induced cellular senescence in ARPE-19 cells, as well as improved the visual function in hHTRA1-Tg mice treated with NaIO₃.

CONCLUSIONS

Our study showed elevated HTRA1 contributes to the pathogenesis of AMD by promoting cellular senescence in RPE through damaging mitochondrial function and activating HIF-1 signaling. It also pointed out that inhibition of HIF-1 signaling might serve as a potential therapeutic strategy for AMD. Video Abstract.

Rethinking the potential and necessity of drug delivery systems in neovascular age-related macular degeneration therapy

Age-related macular degeneration (AMD) is the predominant threat to human vision and ultimately results in blindness. With the increase in the aging population, it has become a more crucial issue to human health. AMD is a multifactorial disease with the unique feature of uncontrollable angiogenesis during initiation and progression. Although increasing evidence indicates that AMD is largely hereditary, the predominant efficient treatment is antiangiogenesis, which mainly involves VEGF and HIF-α as therapeutic targets. The repeated administration of this treatment over the long term, generally through intravitreal injection, has called for the introduction of long-term drug delivery systems, which are expected to be achieved by biomaterials. However, the clinical results of the port delivery system indicate that the optimization of medical devices toward prolonging the activities of therapeutic biologics in AMD therapy seems more promising. These results indicate that we should rethink the possibility and potential of biomaterials as drug delivery systems in achieving long-term, sustained inhibition of angiogenesis in AMD therapy. In this review, the etiology, categorization, risk factors, pathogenesis, and current clinical treatments of AMD are briefly introduced. Next, the development status of long-term drug delivery systems is discussed, and the drawbacks and shortages of these systems are emphasized. By comprehensively considering the pathological aspect and the recent application of drug delivery systems in AMD therapy, we hope to find a better solution for the further development of long-term therapeutic strategies for AMD.

Three Major Causes of Metabolic Retinal Degenerations and Three Ways to Avoid Them

An imbalance of homeostasis in the retina leads to neuron loss and this eventually results in a deterioration of vision. If the stress threshold is exceeded, different protective/survival mechanisms are activated. Numerous key molecular actors contribute to prevalent metabolically induced retinal diseases-the three major challenges are age-related alterations, diabetic retinopathy and glaucoma. These diseases have complex dysregulation of glucose-, lipid-, amino acid or purine metabolism. In this review, we summarize current knowledge on possible ways of preventing or circumventing retinal degeneration by available methods. We intend to provide a unified background, common prevention and treatment rationale for these disorders and identify the mechanisms through which these actions protect the retina. We suggest a role for herbal medicines, internal neuroprotective substances and synthetic drugs targeting four processes: parainflammation and/or glial cell activation, ischemia and related reactive oxygen species and vascular endothelial growth factor accumulation, apoptosis and/or autophagy of nerve cells and an elevation of ocular perfusion pressure and/or intraocular pressure. We conclude that in order to achieve substantial preventive or therapeutic effects, at least two of the mentioned pathways should be targeted synergistically. A repositioning of some drugs is considered to use them for the cure of the other related conditions.

Physicochemical and Biological Stability Assessment of SB11 (Ranibizumab Biosimilar) Under Ambient and In-Use Storage for Intravitreal Administration

INTRODUCTION

SB11 (Byooviz™) is a ranibizumab biosimilar that acts as a vascular endothelial growth factor (VEGF)-A inhibitor. Stability data for unopened SB11 vials at room temperature are limited and no data are available for SB11 withdrawn into syringes (in-use) for intravitreal administration.

METHODS

SB11 stability was assessed in two different settings: unopened vials stored at 30 ± 2 °C/65 ± 5% relative humidity (RH) for 2 months, and in-use SB11 withdrawn into syringes stored at 5 ± 3 °C for 98 days and then 25 ± 2 °C/60 ± 5% RH for 24 h. The product was stored in the absence of light, and the experimental design followed International Conference on Harmonization and European Medicines Agency requirements for stability evaluation of biological products. Analysis included visual appearance (color, clarity, and presence of visible particles), pH, protein concentration (A₂₈₀) and purity (size-exclusion high-pressure liquid chromatography, capillary electrophoresis-sodium dodecyl sulfate, imaged capillary isoelectric focusing), biological activity (VEGF binding and neutralization), and safety (sub-visible particulates).

RESULTS

Except for charge variants in unopened vials at room temperature after 1 month by US standards, all results met the stability acceptance criteria (US and EU) for both unopened vials and for in-use SB11. There were no major changes in terms of physicochemical stability, biological activity and sub-visible particulates.

CONCLUSION

SB11 was stable for longer periods and at higher temperatures than what is stated in the labels of the reference product (Lucentis) and SB11. The physicochemical properties, biological activity, and sub-visible particulates of SB11 in both tested settings (unopened vials at room temperature and in-use product withdrawn into syringes) were maintained under the described storage periods. This information can help to avoid unnecessary delays in patient treatment without any loss in quality and biological activity, lower the workload of health care providers and reduce costs associated with drug waste.

A Novel "Inside-Out" Intraocular Nanomedicine Delivery Mode for Nanomaterials' Biological Effect Enhanced Choroidal Neovascularization Occlusion and Microenvironment Regulation

Photodynamic therapy (PDT) is commonly used in choroidal neovascularization (CNV) treatment due to the superior light transmittance of the eye. However, PDT often leads to surrounding tissue damage and further microenvironmental deterioration, including exacerbated hypoxia, inflammation, and secondary neovascularization. In this work, Pt nanoparticles (NPs) and Au NPs decorated zeolitic imidazolate framework-8 nanoplatform is developed to load indocyanine green for precise PDT and microenvironment amelioration, which can penetrate the internal limiting membrane through Müller cells endocytosis and target to CNV by surface-grafted cyclo(Arg-Gly-Asp-d-Phe-Lys) after intravitreal injection. The excessive H₂ O₂ in the CNV microenvironment is catalyzed by catalase-like Pt NPs for hypoxia relief and enhanced PDT occlusion of neovascular. Meanwhile, Au NPs show significant anti-inflammatory and anti-angiogenesis properties in regulating macrophages and blocking vascular endothelial growth factor (VEGF). Compared with verteporfin treatment, the mRNA expressions of hypoxia-inducible factor-1α and VEGF in the nanoplatform group are downregulated by 90.2% and 81.7%, respectively. Therefore, the nanoplatform realizes a comprehensive CNV treatment effect based on the high drug loading capacity and biosafety. The CNV treatment mode developed in this work provides a valuable reference for treating other diseases with similar physiological barriers that limit drug delivery and similar microenvironment.

Risk of developing age-related macular degeneration in patients with osteoporosis: a population-based, longitudinal follow-up study

Osteoporosis was suggested to be associated with higher odds of age-related macular degeneration. However, the temporal relationship between osteoporosis and age-related macular degeneration has not been explored. This population-based longitudinal follow-up study showed an increased risk of age-related macular degeneration in both men and women with osteoporosis.

PURPOSE

To investigate the long-term risk of age-related macular degeneration (AMD) in patients with osteoporosis.

METHODS

This is a retrospective cohort study using the Longitudinal Health Insurance Database 2005, a subset of Taiwan's National Health Insurance research database. A total of 23,611 individuals aged 50 to 79 who were diagnosed with osteoporosis between January 1, 2002 and December 31, 2006, were enrolled in the osteoporosis group. An exactly equal number of propensity score-matched individuals without osteoporosis comprised the comparison group. The variables used in propensity score matching included age, sex, comorbidities, and socioeconomic status. Cox proportional hazard regression analysis was used to evaluate the association between osteoporosis and AMD. The main outcome measure is the occurrence of newly diagnosed AMD.

RESULTS

The hazard ratio (HR) of AMD in the osteoporosis group was 1.34 times higher than in the comparison group (95% confidence interval [CI] 1.22-1.47, p < 0.05). The AMD-free survival rate of the osteoporosis group was significantly lower than that of the comparison group (p < 0.0001). Sex-stratified analysis revealed a significantly increased risk of AMD in both osteoporotic men (HR 1.45; 95% CI 1.20-1.76, p = 0.0002) and women (HR 1.31; 95% CI 1.17-1.46, p < 0.0001) compared with their non-osteoporotic counterparts.

CONCLUSION

This longitudinal follow-up study revealed an increased risk of developing AMD in both men and women with osteoporosis.

Emerging therapeutic strategies for unmet need in neovascular age-related macular degeneration

Neovascular age-related macular degeneration (nAMD) is a major cause of visual impairment and blindness. Anti-vascular endothelial growth factor (VEGF) agents, such as ranibizumab, bevacizumab, aflibercept, brolucizumab and faricimab have revolutionized the clinical management of nAMD. However, there remains an unmet clinical need for new and improved therapies for nAMD, since many patients do not respond optimally, may lose response over time or exhibit sub-optimal durability, impacting on real world effectiveness. Evidence is emerging that targeting VEGF-A alone, as most agents have done until recently, may be insufficient and agents that target multiple pathways (e.g., aflibercept, faricimab and others in development) may be more efficacious. This article reviews issues and limitations that have arisen from the use of existing anti-VEGF agents, and argues that the future may lie in multi-targeted therapies including alternative agents and modalities that target both the VEGF ligand/receptor system as well as other pathways.

New insight of metabolomics in ocular diseases in the context of 3P medicine

Metabolomics refers to the high-through untargeted or targeted screening of metabolites in biofluids, cells, and tissues. Metabolome reflects the functional states of cells and organs of an individual, influenced by genes, RNA, proteins, and environment. Metabolomic analyses help to understand the interaction between metabolism and phenotype and reveal biomarkers for diseases. Advanced ocular diseases can lead to vision loss and blindness, reducing patients' quality of life and aggravating socio-economic burden. Contextually, the transition from reactive medicine to the predictive, preventive, and personalized (PPPM / 3P) medicine is needed. Clinicians and researchers dedicate a lot of efforts to explore effective ways for disease prevention, biomarkers for disease prediction, and personalized treatments, by taking advantages of metabolomics. In this way, metabolomics has great clinical utility in the primary and secondary care. In this review, we summarized much progress achieved by applying metabolomics to ocular diseases and pointed out potential biomarkers and metabolic pathways involved to promote 3P medicine approach in healthcare.

Retinal Pigment Epithelial Abnormality and Choroidal Large Vascular Flow Imbalance Are Associated with Choriocapillaris Flow Deficits in Age-Related Macular Degeneration in Fellow Eyes

Choriocapillaris flow deficits detected on optical coherence tomography angiographs were retrospectively analyzed. In 38 age-related macular degeneration (AMD) fellow eyes, without fundus findings (26 men, 71.7 ± 1.9 years old), and 22 control eyes (11 men, 69.4 ± 1.8), the choriocapillaris flow area (CCFA) ratio and coefficient of variation (CV) of the CCFA ratio (which represented the heterogeneity of the ratio), negatively and positively correlated with age (all p < 0.01), respectively. Moreover, the respective mean values were lower (p = 0.0031) and greater (p = 0.002) in AMD fellow eyes than in the control eyes. The high-risk condition of AMD fellow eyes was defined by a CCFA ratio <58.5%, and the CV of the CCFA ratio ≥0.165 (odds ratio (OR), 5.408; 95% confidence interval (CI): 1.117-21.118, p = 0.035, after adjusting for age and sex) was related to the presence of fundus autofluorescence abnormality (OR, 16.440; 95% CI, 1.262-214.240; p = 0.033) and asymmetrically dilated choroidal large vasculature (OR, 4.176; 95% CI, 1.057-16.503; p = 0.042), after adjusting for age and sex. The presence of fundus autofluorescence abnormality indicated a retinal pigment epithelium (RPE) abnormality. The RPE volume was reduced in the latter eye group, particularly in the thinner choroidal vasculature. In addition to aging, RPE abnormality and choroidal large vascular flow imbalances were associated with exacerbated heterogeneous choriocapillaris flow deficits in AMD fellow eyes without macular neovascularization.

"One stone and two birds" strategy to treat neovascular age-related macular degeneration by a novel retinoid drug, EYE-101

Choroidal neovascularization (CNV) is a typical pathological feature of neovascular age-related macular degeneration and has become a major cause of vision loss in the elderly. Current therapies require repeated intraocular injections of anti-VEGF drugs by inhibiting endothelial angiogenic effects, which is painful and may cause adverse effects on normal vascular and neuronal functions. Herein, we designed a novel retinoid drug, EYE-101, determined its therapeutic effects on CNV, and clarified the anti-angiogenic mechanism. The results show that administration of EYE-101 did not cause obvious cytotoxicity and ocular tissue toxicity at the concentrations less than 5 μM. Topical administration of EYE-101 could reduce choroidal sprouting, suppress laser-induced CNV formation, and decrease pericyte coverages on ocular vessels. Administration of EYE-101 also suppressed endothelial cell proliferation, migration, and tube formation and reduced pericyte proliferation, migration, recruitment towards endothelial cells. EYE-101 exerted its anti-angiogenic effects by targeting endothelial cells and pericytes via antagonizing Wnt/β-catenin signaling and PDGF signaling. Thus, EYE-101 administration may offer an"one stone and two birds" strategy for the prevention and treatment of ocular neovascular disorders.

OCT and OCT Angiography Update: Clinical Application to Age-Related Macular Degeneration, Central Serous Chorioretinopathy, Macular Telangiectasia, and Diabetic Retinopathy

Similar to ultrasound adapting soundwaves to depict the inner structures and tissues, optical coherence tomography (OCT) utilizes low coherence light waves to assess characteristics in the eye. Compared to the previous gold standard diagnostic imaging fluorescein angiography, OCT is a noninvasive imaging modality that generates images of ocular tissues at a rapid speed. Two commonly used iterations of OCT include spectral-domain (SD) and swept-source (SS). Each comes with different wavelengths and tissue penetration capacities. OCT angiography (OCTA) is a functional extension of the OCT. It generates a large number of pixels to capture the tissue and underlying blood flow. This allows OCTA to measure ischemia and demarcation of the vasculature in a wide range of conditions. This review focused on the study of four commonly encountered diseases involving the retina including age-related macular degeneration (AMD), diabetic retinopathy (DR), central serous chorioretinopathy (CSC), and macular telangiectasia (MacTel). Modern imaging techniques including SD-OCT, TD-OCT, SS-OCT, and OCTA assist with understanding the disease pathogenesis and natural history of disease progression, in addition to routine diagnosis and management in the clinical setting. Finally, this review compares each imaging technique's limitations and potential refinements.

Proteomics profiling of vitreous humor reveals complement and coagulation components, adhesion factors, and neurodegeneration markers as discriminatory biomarkers of vitreoretinal eye diseases

Introduction

Diabetic retinopathy (DR) and age-related macular degeneration (AMD) are leading causes of visual impairment and blindness in people aged 50 years or older in middle-income and industrialized countries. Anti-VEGF therapies have improved the management of neovascular AMD (nAMD) and proliferative DR (PDR), no treatment options exist for the highly prevalent dry form of AMD.

Methods

To unravel the biological processes underlying these pathologies and to find new potential biomarkers, a label-free quantitative (LFQ) method was applied to analyze the vitreous proteome in PDR (n=4), AMD (n=4) compared to idiopathic epiretinal membranes (ERM) (n=4).

Results and discussion

Post-hoc tests revealed 96 proteins capable of differentiating among the different groups, whereas 118 proteins were found differentially regulated in PDR compared to ERM and 95 proteins in PDR compared to dry AMD. Pathway analysis indicates that mediators of complement, coagulation cascades and acute phase responses are enriched in PDR vitreous, whilst proteins highly correlated to the extracellular matrix (ECM) organization, platelet degranulation, lysosomal degradation, cell adhesion, and central nervous system development were found underexpressed. According to these results, 35 proteins were selected and monitored by MRM (multiple reaction monitoring) in a larger cohort of patients with ERM (n=21), DR/PDR (n=20), AMD (n=11), and retinal detachment (n=13). Of these, 26 proteins could differentiate between these vitreoretinal diseases. Based on Partial least squares discriminant and multivariate exploratory receiver operating characteristic (ROC) analyses, a panel of 15 discriminatory biomarkers was defined, which includes complement and coagulation components (complement C2 and prothrombin), acute-phase mediators (alpha-1-antichymotrypsin), adhesion molecules (e.g., myocilin, galectin-3-binding protein), ECM components (opticin), and neurodegeneration biomarkers (beta-amyloid, amyloid-like protein 2).

Targeting Necroptosis: A Novel Therapeutic Option for Retinal Degenerative Diseases

The discovery of the necroptosis, a form of regulated necrosis that is mediated by receptor-interacting protein kinase 1 (RIPK1), RIPK3, and mixed-lineage kinase domain-like pseudokinase (MLKL), represents a major breakthrough that has dramatically altered the conception of necrosis - traditionally thought of as uncontrolled cell death - in various human diseases. Retinal cell death is a leading cause of blindness and has been identified in most retinal diseases, e.g., age-related macular degeneration, glaucoma, retinal detachment, retinitis pigmentosa, etc. Increasing evidence demonstrates that retinal degenerative diseases also share a common mechanism in necroptosis. Exacerbated necroptotic cell death hinders the treatment for retinal degenerative diseases. In this review, we highlight recent advances in identifying retinal necroptosis, summarize the underlying mechanisms of necroptosis in retinal degenerative diseases, and discuss potential anti-necroptosis strategies, such as selective inhibitors and chemical agents, for treating retinal degenerative diseases.

Joint effects of meteorological factors and PM2.5 on age-related macular degeneration: a national cross-sectional study in China

BACKGROUND

Weather conditions are a possible contributing factor to age-related macular degeneration (AMD), a leading cause of irreversible loss of vision. The present study evaluated the joint effects of meteorological factors and fine particulate matter (PM_2.5) on AMD.

METHODS

Data was extracted from a national cross-sectional survey conducted across 10 provinces in rural China. A total of 36,081 participants aged 40 and older were recruited. AMD was diagnosed clinically by slit-lamp ophthalmoscopy, fundus photography, and spectral domain optical coherence tomography (OCT). Meteorological data were calculated by European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis and were matched to participants' home addresses by latitude and longitude. Participants' individual PM_2.5 exposure concentrations were calculated by a satellite-based model at a 1-km resolution level. Multivariable-adjusted logistic regression models paired with interaction analysis were performed to investigate the joint effects of meteorological factors and PM_2.5 on AMD.

RESULTS

The prevalence of AMD in the study population was 2.6% (95% CI 2.42-2.76%). The average annual PM_2.5 level during the study period was 63.1 ± 15.3 µg/m³. A significant positive association was detected between AMD and PM_2.5 level, temperature (T), and relative humidity (RH), in both the independent and the combined effect models. For PM_2.5, compared with the lowest quartile, the odds ratios (ORs) with 95% confidence intervals (CIs) across increasing quartiles were 0.828 (0.674,1.018), 1.105 (0.799,1.528), and 2.602 (1.516,4.468). Positive associations were observed between AMD and temperature, with ORs (95% CI) of 1.625 (1.059,2.494), 1.619 (1.026,2.553), and 3.276 (1.841,5.830), across increasing quartiles. In the interaction analysis, the estimated relative excess risk due to interaction (RERI) and the attributable proportion (AP) for combined atmospheric pressure and PM_2.5 was 0.864 (0.586,1.141) and 1.180 (0.768,1.592), respectively, indicating a synergistic effect between PM_2.5 and atmospheric pressure.

CONCLUSIONS

This study is among the first to characterize the coordinated effects of meteorological factors and PM_2.5 on AMD. The findings warrant further investigation to elucidate the relationship between ambient environment and AMD.

The role of NAD+ metabolism in macrophages in age-related macular degeneration

Age-related macular degeneration (AMD) is a leading cause of legal blindness and moderate and severe vision impairment (MSVI) in people older than 50 years. It is classified in various stages including early, intermediate, and late stage. In the early stages, innate immune system, especially macrophages, play an essential part in disease onset and progression. NAD⁺ is an essential coenzyme involved in cellular senescence and immune cell function, and its role in age-related diseases is gaining increasing attention. The imbalance between the NAD⁺ synthesis and consumption causes the fluctuation of intracellular NAD⁺ level which determines the polarization fate of macrophages. In AMD, the over-expression of NAD⁺-consuming enzymes in macrophages leads to declining of NAD⁺ concentrations in the microenvironment. This phenomenon triggers the activation of inflammatory pathways in macrophages, positive feedback aggregation of inflammatory cells and accumulation of reactive oxygen species (ROS). This review details the role of NAD⁺ metabolism in macrophages and molecular mechanisms during AMD. The selected pathways were identified as potential targets for intervention in AMD, pending further investigation.