β-secretase 1 overexpression by AAV-mediated gene delivery prevents retina degeneration in a mouse model of age-related macular degeneration

We reported previously that β-site amyloid precursor protein cleaving enzyme (BACE1) is strongly expressed in the normal retina and that BACE1-/- mice develop pathological phenotypes associated with age-related macular degeneration (AMD). BACE1 expression is increased within the neural retina and retinal pigment epithelium (RPE) in AMD donor eyes suggesting that increased BACE1 is compensatory. We observed that AAV-mediated BACE1 overexpression in the RPE was maintained up to 6 months after AAV1-BACE1 administration. No significant changes in normal mouse visual function or retinal morphology were observed with low-dose vector while the high-dose vector demonstrated some early pathology which regressed with time. No increase in β-amyloid was observed. BACE1 overexpression in the RPE of the superoxide dismutase 2 knockdown (SOD2 KD) mouse, which exhibits an AMD-like phenotype, prevented loss of retinal function and retinal pathology, and this was sustained out to 6 months. Furthermore, BACE1 overexpression was able to inhibit oxidative stress, microglial changes, and loss of RPE tight junction integrity (all features of AMD) in SOD2 KD mice. In conclusion, BACE1 plays a key role in retina/RPE homeostasis, and BACE1 overexpression offers a novel therapeutic target in the treatment of AMD.

Chemiexcitation and melanin in photoreceptor disc turnover and prevention of macular degeneration

Age-related macular degeneration, Stargardt disease, and their Abca4-/- mouse model are characterized by accelerated accumulation of the pigment lipofuscin, derived from photoreceptor disc turnover in the retinal pigment epithelium (RPE); lipofuscin accumulation and retinal degeneration both occur earlier in albino mice. Intravitreal injection of superoxide (O2•-) generators reverses lipofuscin accumulation and rescues retinal pathology, but neither the target nor mechanism is known. Here we show that RPE contains thin multi-lamellar membranes (TLMs) resembling photoreceptor discs, which associate with melanolipofuscin granules in pigmented mice but in albinos are 10-fold more abundant and reside in vacuoles. Genetically over-expressing tyrosinase in albinos generates melanosomes and decreases TLM-related lipofuscin. Intravitreal injection of generators of O2•- or nitric oxide (•NO) decreases TLM-related lipofuscin in melanolipofuscin granules of pigmented mice by ~50% in 2 d, but not in albinos. Prompted by evidence that O2•- plus •NO creates a dioxetane on melanin that excites its electrons to a high-energy state (termed "chemiexcitation"), we show that exciting electrons directly using a synthetic dioxetane reverses TLM-related lipofuscin even in albinos; quenching the excited-electron energy blocks this reversal. Melanin chemiexcitation assists in safe photoreceptor disc turnover.

Potential roles of dietary zeaxanthin and lutein in macular health and function

Lutein, zeaxanthin, and meso-zeaxanthin are three xanthophyll carotenoid pigments that selectively concentrate in the center of the retina. Humans cannot synthesize lutein and zeaxanthin, so these compounds must be obtained from the diet or supplements, with meso-zeaxanthin being converted from lutein in the macula. Xanthophylls are major components of macular pigments that protect the retina through the provision of oxidant defense and filtering of blue light. The accumulation of these three xanthophylls in the central macula can be quantified with non-invasive methods, such as macular pigment optical density (MPOD). MPOD serves as a useful tool for assessing risk for, and progression of, age-related macular degeneration, the third leading cause of blindness worldwide. Dietary surveys suggest that the dietary intakes of lutein and zeaxanthin are decreasing. In addition to low dietary intake, pregnancy and lactation may compromise the lutein and zeaxanthin status of both the mother and infant. Lutein is found in modest amounts in some orange- and yellow-colored vegetables, yellow corn products, and in egg yolks, but rich sources of zeaxanthin are not commonly consumed. Goji berries contain the highest known levels of zeaxanthin of any food, and regular intake of these bright red berries may help protect against the development of age-related macular degeneration through an increase in MPOD. The purpose of this review is to summarize the protective function of macular xanthophylls in the eye, speculate on the compounds' role in maternal and infant health, suggest the establishment of recommended dietary values for lutein and zeaxanthin, and introduce goji berries as a rich food source of zeaxanthin.

Repurposing medications for treatment of age-related macular degeneration: Insights from novel approaches to data mining

The economic and visual burdens associated with age-related macular degeneration (AMD) are expected to significantly increase in the coming years. As of now, interventions to delay or prevent AMD are limited. Hence, there is an urgent and unmet need to expand our therapeutic tools for AMD in a manner, that is, both efficient and cost-effective. In this review, we consider the idea of drug repurposing, in which existing medications with other indications can be re-imagined for treating AMD. We detail the results of several population-level studies that have shown associations between several candidates and decreased risk of AMD development or progression. Such candidates include the more extensively studied metformin and statins, in addition to recently identified candidates fluoxetine and l-DOPA (levodopa) that show promise. We then briefly explore results from an advanced bioinformatics study, which provides further evidence that existing medications are associated with AMD risk genes. Many of these candidates warrant further study in prospective, clinical trials, where their potential causal relationships with AMD can be thoroughly assessed.

The relationship between dietary patterns and ophthalmic disease

PURPOSE OF REVIEW

There is a rising interest in the impact of diet on the pathogenesis of common ophthalmic conditions. The purpose of this review is to summarize the potential preventive and therapeutic power of dietary interventions described in recent basic science and epidemiological literature.

RECENT FINDINGS

Basic science investigations have elucidated a variety of mechanisms by which diet may impact ophthalmic disease, particularly through its action on chronic oxidative stress, inflammation and macular pigmentation. Epidemiologic investigations have shown the real-world influence of diet on the incidence and progression of a number of ophthalmic diseases, particularly cataract, age-related macular degeneration (AMD) and diabetic retinopathy. A large observational cohort study found a 20% reduction in the incidence of cataract among vegetarians compared with nonvegetarians. Two recent systematic reviews found that higher adherence to Mediterranean dietary patterns was associated with a decreased risk of progression of AMD to later stages. Finally, large meta-analyses found that patients following plant-based and Mediterranean diets had significant reductions of mean haemoglobin A1c scores and incidence of diabetic retinopathy as compared with controls.

SUMMARY

There is a significant and growing body of evidence that Mediterranean diet and plant-based diets - those that maximize fruits, vegetables, legumes, whole grains and nuts; and that minimize animal products and processed foods - help prevent vision loss from cataract, AMD and diabetic retinopathy. These diets may hold benefits for other ophthalmic conditions, as well. Nevertheless, there is a need for further randomized, controlled and longitudinal studies in this area.

Chitooligosaccharides Derivatives Protect ARPE-19 Cells against Acrolein-Induced Oxidative Injury

Age-related macular degeneration (AMD) is the leading cause of vision loss among the elderly. The progression of AMD is closely related to oxidative stress in the retinal pigment epithelium (RPE). Here, a series of chitosan oligosaccharides (COSs) and N-acetylated derivatives (NACOSs) were prepared, and their protective effects on an acrolein-induced oxidative stress model of ARPE-19 were explored using the MTT assay. The results showed that COSs and NACOs alleviated APRE-19 cell damage induced by acrolein in a concentration-dependent manner. Among these, chitopentaose (COS–5) and its N-acetylated derivative (N–5) showed the best protective activity. Pretreatment with COS–5 or N–5 could reduce intracellular and mitochondrial reactive oxygen species (ROS) production induced by acrolein, increase mitochondrial membrane potential, GSH level, and the enzymatic activity of SOD and GSH-Px. Further study indicated that N–5 increased the level of nuclear Nrf2 and the expression of downstream antioxidant enzymes. This study revealed that COSs and NACOSs reduced the degeneration and apoptosis of retinal pigment epithelial cells by enhancing antioxidant capacity, suggesting that they have the potential to be developed into novel protective agents for AMD treatment and prevention.

Association of Metformin With the Development of Age-Related Macular Degeneration

Importance

Age-related macular degeneration (AMD) is a leading cause of blindness with no treatment available for early stages. Retrospective studies have shown an association between metformin and reduced risk of AMD.

Objective

To investigate the association between metformin use and age-related macular degeneration (AMD).

Design, Setting, and Participants

The Diabetes Prevention Program Outcomes Study is a cross-sectional follow-up phase of a large multicenter randomized clinical trial, Diabetes Prevention Program (1996-2001), to investigate the association of treatment with metformin or an intensive lifestyle modification vs placebo with preventing the onset of type 2 diabetes in a population at high risk for developing diabetes. Participants with retinal imaging at a follow-up visit 16 years posttrial (2017-2019) were included. Analysis took place between October 2019 and May 2022.

Interventions

Participants were randomly distributed between 3 interventional arms: lifestyle, metformin, and placebo.

Main Outcomes and Measures

Prevalence of AMD in the treatment arms.

Results

Of 1592 participants, 514 (32.3%) were in the lifestyle arm, 549 (34.5%) were in the metformin arm, and 529 (33.2%) were in the placebo arm. All 3 arms were balanced for baseline characteristics including age (mean [SD] age at randomization, 49 [9] years), sex (1128 [71%] male), race and ethnicity (784 [49%] White), smoking habits, body mass index, and education level. AMD was identified in 479 participants (30.1%); 229 (14.4%) had early AMD, 218 (13.7%) had intermediate AMD, and 32 (2.0%) had advanced AMD. There was no significant difference in the presence of AMD between the 3 groups: 152 (29.6%) in the lifestyle arm, 165 (30.2%) in the metformin arm, and 162 (30.7%) in the placebo arm. There was also no difference in the distribution of early, intermediate, and advanced AMD between the intervention groups. Mean duration of metformin use was similar for those with and without AMD (mean [SD], 8.0 [9.3] vs 8.5 [9.3] years; P = .69). In the multivariate models, history of smoking was associated with increased risks of AMD (odds ratio, 1.30; 95% CI, 1.05-1.61; P = .02).

Conclusions and Relevance

These data suggest neither metformin nor lifestyle changes initiated for diabetes prevention were associated with the risk of any AMD, with similar results for AMD severity. Duration of metformin use was also not associated with AMD. This analysis does not address the association of metformin with incidence or progression of AMD.

Lutein and zeaxanthin - radio- and chemoprotective properties. Mechanism and possible use

Lutein and zeaxanthin are naturally occurring xanthophylls, mainly present in green, leafy vegetables and egg's yolk. Their presence is connected with blue spectrum light absorbance, including UV. This property, and fact, that these xanthophylls are accumulated by human eye's macula, leads to eye's protective functions of them including protection from age-related macular degeneration (AMD). Also, antioxidative features of lutein and zeaxanthin are boosting overall health of human body. Numerous studies proves anti-inflammatory and protective attributes of these compounds, based on many, different mechanisms. One of them is regulating redox potential in cells, and impact on expression of linked genes. In preventing of eye diseases, an important gene that is regulated by lutein and zeaxanthin is the Nrf2 gene, whose increased activity leads to optimizing the cellular response to reactive oxygen species (ROS) and preventing related diseases. Other research confirms antiproliferative properties of mentioned compounds in case of certain human cancer cell lines. There are e.g.: HepG2 (hepatitis cancer), MCF-7 (breast cancer), which treated in vitro with lutein solution showed reduction of cell growth. Lutein alone, during in vivo studies conducted on mice, exhibited also radioprotective properties, positively affecting the vitality of animals. Lutein provides also increasing of tolerance to UV radiation, reducing inflammatory processes in the skin and preventing oncogenesis. Low intake of lutein and zeaxanthin, associated with "western diet", rich in simple carbohydrates and processed food, common in developed countries, including Poland, is linked with diabetes and obesity incidence. Assuming, lutein and zeaxanthin significantly affect the well-being of the human body, and their appropriate amount in diet can help reduce risk of many diseases. For supplementation, the optimized dosage of these xanthophylls includes doses of 10 mg for lutein and 2 mg for zeaxanthin, and it is recommended to consume along with fats or meals rich in fats.

What did we learn in 35 years of research on nutrition and supplements for age-related macular degeneration: a systematic review

The aim of this paper is to summarize all available evidence from systematic reviews, randomized controlled trials (RCTs) and comparative nonrandomized studies (NRS) on the association between nutrition and antioxidant, vitamin, and mineral supplements and the development or progression of age-related macular degeneration (AMD). The Cochrane Database of Systematic Reviews, Cochrane register CENTRAL, MEDLINE and Embase were searched and studies published between January 2015 and May 2021 were included. The certainty of evidence was assessed according to the GRADE methodology. The main outcome measures were development of AMD, progression of AMD, and side effects. We included 7 systematic reviews, 7 RCTs, and 13 NRS. A high consumption of specific nutrients, i.e. β-carotene, lutein and zeaxanthin, copper, folate, magnesium, vitamin A, niacin, vitamin B6, vitamin C, docosahexaenoic acid, and eicosapentaenoic acid, was associated with a lower risk of progression of early to late AMD (high certainty of evidence). Use of antioxidant supplements and adherence to a Mediterranean diet, characterized by a high consumption of vegetables, whole grains, and nuts and a low consumption of red meat, were associated with a decreased risk of progression of early to late AMD (moderate certainty of evidence). A high consumption of alcohol was associated with a higher risk of developing AMD (moderate certainty of evidence). Supplementary vitamin C, vitamin E, or β-carotene were not associated with the development of AMD, and supplementary omega-3 fatty acids were not associated with progression to late AMD (high certainty of evidence). Research in the last 35 years included in our overview supports that a high intake of specific nutrients, the use of antioxidant supplements and adherence to a Mediterranean diet decrease the risk of progression of early to late AMD.

The Effect of Dietary Supplementations on Delaying the Progression of Age-Related Macular Degeneration: A Systematic Review and Meta-Analysis

Purpose: Age-related macular degeneration (AMD) is a neurodegenerative ophthalmic disease. The purpose of this systematic review (SR) and meta-analysis was to evaluate if dietary supplementation alone or in combinations might delay the progression of any of the stages of AMD. Methods: A SR and meta-analysis identifying cohort studies and randomized controlled trials (RCTs) evaluating the effect of supplements in patients diagnosed with AMD. PubMed, Scopus, Web of Science, CINAHL, and Cochrane were searched through 8th October 2021. Results: Twenty studies, examining 5634 participants ranging from 55 to 80 years, were included in the SR. Eight studies were selected for meta-analysis (414 and 216 subjects in the intervention and control groups). Lutein and zeaxanthin plus n-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA) supplementation showed significant improvements in best-corrected visual acuity (BCVA) (SMD: -1.99, 95% CI: -3.33, -0.65) compared to the control group. Multifocal electroretinogram results (mfERG) were significantly improved overall (SMD: 4.59, 95% CI: 1.75, 7.43) after lutein plus zeaxanthin supplementation. Conclusions: Combinations of lutein and zeaxanthin with n-3 LC-PUFA might be beneficial in preventing AMD progression and deterioration of visual function. Our results encourage initiating further studies with combinations of n-3 LC-PUFA, lutein, and zeaxanthin especially in early AMD patients.

Dietary omega-3 LCPUFA intake in the prevention of neovascular age-related macular degeneration: a systematic review and meta-analysis

Purpose: to evaluate the protective effect of omega-3 long-chain unsaturated fatty acids on the progression of wet age-related macular degeneration (wAMD). Methods: this meta-analysis was designed, implemented, and analyzed in accordance with the Meta-analysis of Observational Studies in Epidemiology (MOOSE) protocol and is reported following PRISMA guidelines. Results: in this study we included 5 observational trials, including 2 cross-sectional studies, 2 case-control studies, and 1 confrontation study. These tests are conducted in the U.S., Europe and Japan, and are of high quality. In general, people with high dietary long-chain omega-3 polyunsaturated fatty acids (omega-3 LCPUFAs) have a lower risk of progression to advanced age-related macular degeneration (AMD) (effect size, ES: 0.51, 95 % CI [0.34, 0.75], I2 = 70 %, p = 0.01). When assessing docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) intake and wAMD risk a total of the three above studies were included, which also produced similar results. Conclusions: the highest DHA consumption reduced the risk of disease by 39 % (effect size: 0.61, 95 % CI [0.50, 0.74], I2 = 14 %, p = 0.31); compared with the lowest EPA consumption, the highest EPA consumption reduced the risk of wAMD by 32 % (ES: 0.68, 95 % CI [0.57, 0.82], I2 = 39 %, p = 0.20).

The Blue Light Hazard Versus Blue Light Hype

PURPOSE

The blue light hazard is the experimental finding that blue light is highly toxic to the retina (photic retinopathy), in brief abnormally intense exposures, including sungazing or vitreoretinal endoillumination. This term has been misused commercially to suggest, falsely, that ambient environmental light exposure causes phototoxicity to the retina, leading to age-related macular degeneration (AMD). We analyze clinical, epidemiologic, and biophysical data regarding blue-filtering optical chromophores.

DESIGN

Perspective.

METHODS

Analysis and integration of data regarding the blue light hazard and blue-blocking filters in ophthalmology and related disciplines.

RESULTS

Large epidemiologic studies show that blue-blocking intraocular lenses (IOLs) do not decrease AMD risk or progression. Blue-filtering lenses cannot reduce disability glare because image and glare illumination are decreased in the same proportion. Blue light essential for optimal rod and retinal ganglion photoreception is decreased by progressive age-related crystalline lens yellowing, pupillary miosis, and rod and retinal ganglion photoreceptor degeneration. Healthful daily environmental blue light exposure decreases in older adults, especially women. Blue light is important in dim environments where inadequate illumination increases risk of falls and associated morbidities.

CONCLUSIONS

The blue light hazard is misused as a marketing stratagem to alarm people into using spectacles and IOLs that restrict blue light. Blue light loss is permanent for pseudophakes with blue-blocking IOLs. Blue light hazard misrepresentation flourishes despite absence of proof that environmental light exposure or cataract surgery causes AMD or that IOL chromophores provide clinical protection. Blue-filtering chromophores suppress blue light critical for good mental and physical health and for optimal scotopic and mesopic vision.

Adherence to the Mediterranean-Style Eating Pattern and Macular Degeneration: A Systematic Review of Observational Studies

Age-related macular degeneration (AMD) is a serious degenerative disease affecting the eyes, and is the main cause of severe vision loss among people >55 years of age in developed countries. Its onset and progression have been associated with several genetic and lifestyle factors, with diet appearing to play a pivotal role in the latter. In particular, dietary eating patterns rich in plant foods have been shown to lower the risk of developing the disease, and to decrease the odds of progressing to more advanced stages in individuals already burdened with early AMD. We systematically reviewed the literature to analyse the relationship between the adherence to a Mediterranean diet, a mainly plant-based dietary pattern, and the onset/progression of AMD. Eight human observational studies were analysed. Despite some differences, they consistently indicate that higher adherence to a Mediterranean eating pattern lowers the odds of developing AMD and decreases the risk of progression to more advanced stages of the disease, establishing the way for preventative measures emphasizing dietary patterns rich in plant-foods.

STATIN USE AND THE INCIDENCE OF AGE-RELATED MACULAR DEGENERATION: A Meta-Analysis

PURPOSE

Age-related macular degeneration (AMD) shares many of the same risk factors with atherosclerosis. There is a postulated role of lipid-lowering agents in preventing AMD. This meta-analysis investigates the possible role of statins in the prevention of AMD onset and progression.

METHODS

MEDLINE, EMBASE, Cochrane CENTRAL, and the reference lists of included studies were systematically searched from inception to September 2020. Studies were included if they measured the risk of AMD development or progression with statin use. The primary outcomes assessed were AMD incidence and progression. Secondary outcomes were the incidence of early AMD, late AMD, choroidal neovascularization, and geographic atrophy.

RESULTS

Twenty-one articles (1 randomized control trial and 20 observational studies) collectively reporting on 1,460,989 participants were included. The pooled risk ratios (95% confidence interval) for statin use on any, early, and late AMD incidence were 1.05 (0.85-1.29) (P = 0.44), 0.99 (0.88-1.11) (P = 0.86), and 1.15 (0.90-1.47) (P = 0.27), respectively. In patients with existing AMD, the respective risk ratios for statin use on incidence of AMD progression, choroidal neovascularization, and geographic atrophy were 1.04 (0.70-1.53) (P = 0.85), 0.99 (0.66-1.48) (P = 0.95), and 0.84 (0.58-1.22) (P = 0.36).

CONCLUSION

This meta-analysis found that there was no significant difference in the incidence or progression of AMD based on statin use.

Lutein and Zeaxanthin and Their Roles in Age-Related Macular Degeneration-Neurodegenerative Disease

Lutein and zeaxanthin belong to the xanthophyll family of carotenoids, which are pigments produced by plants. Structurally, they are very similar, differing only slightly in the arrangement of atoms. Key sources of these carotenoids include kale, savoy cabbage, spinach, broccoli, peas, parsley, corn, and egg yolks. The recommended daily intake of lutein is approximately 10.0 mg and that of zeaxanthin is 2 mg. Lutein intake in adults varies, with average intakes being 1-2 mg/day. Due to the lack of synthesis of consumption of these compounds in humans, these substances are extremely important for the proper functioning of certain organs of the body (eye, skin, heart, intestines). Eating a lot of dark leafy vegetables and some fruits can help to prevent our bodies from developing diseases. The protective effects of carotenoids are mainly related to their defense against oxidative stress and their ability to scavenge free radicals. Lutein and zeaxanthin are the only dietary carotenoids that accumulate in the retina, specifically the macula, and are called macular pigments. These carotenoids are concentrated by the action of specific binding proteins such as StARD3, which binds lutein, and GSTP1, which binds zeaxanthin and its dietary metabolite, mesozeaxanthin. It has been shown that supportive therapy with lutein and zeaxanthin can have a beneficial effect in delaying the progression of eye diseases such as age-related macular degeneration (AMD) and cataracts. This article presents the current state of knowledge on the role of lutein and zeaxanthin, especially from human studies targeting their metabolism and bioavailability, with recommendations to consume xanthophyll-rich foods.

Trends in Hawai'i Ophthalmologists' Recommendations to Patients for Prevention of Age-Related Macular Degeneration

The purpose of this study is to determine the current trends in recommendations made to patients by ophthalmologists in Hawai'i regarding the prevention of age-related macular degeneration (AMD) and to compare these recommendations to preventative therapies described in the literature. A review of the literature was done to determine the preventative interventions that can be made to significantly lower the risk of developing AMD. An anonymous survey was sent to 95 ophthalmologists in clinical practice in Hawai'i in 2020. The survey assessed recommendations for the prevention of age-related macular degeneration. The 4 interventions assessed were avoidance of smoking, utilization of antioxidant vitamins called AREDS2, adherence to a Mediterranean diet, and maintaining a normal body mass index (BMI). Responses were received from 41 ophthalmologists were received. Overall, 100% of participants responded "yes" to recommending smoking cessation to their patients, 76% of participants recommended AREDS 2, 42% recommended a Mediterranean diet, and 37% of participants recommended maintaining a normal BMI. Smoking cessation or avoidance was universally recommended by the respondents, and 22% recommended all the assessed interventions. The survey results suggest that some interventions, such as maintaining a normal BMI and adopting a Mediterranean diet are not as widely implemented into ophthalmologists' recommendations compared to others, such as AREDS2 formulation vitamins and smoking cessation.

COL10A1 is a novel factor in the development of choroidal neovascularization

With the dramatic rise in the aging population, researching age-related macular degeneration (AMD), especially the severe form neovascular AMD (nAMD), has become more important than ever. In this study, we found that collagen type X was increased in retina-choroid tissue of mice with laser-induced choroidal neovascularization (CNV) based on immunohistofluorescence. RNA sequencing and bioinformatic analyses were performed to compare the retina-choroid tissue complex of the CNV mouse model to normal controls. Collagen type X alpha 1 chain (Col10a1) was among the most significantly upregulated genes, and the results were validated with an animal model at the mRNA and protein levels by quantitative real-time polymerase chain reaction (qPCR) and western blotting, respectively. COL10A1 was also upregulated in human retinal microvascular endothelial cells (HRMECs), human umbilical vein endothelial cells (HUVECs), RPE19 cells and RF/6A cells under hypoxic conditions. Next, in vitro and in vivo experiments were performed to study the effect of COL10A1 on neovascularization. siRNA knockdown of COL10A1 suppressed the proliferation and tube formation ability of HRMECs under hypoxic conditions. Snail family transcriptional repressor 1 (SNAIL1) and angiopoietin-2 (ANGPT2) were downregulated in COL10A1 knockdown HRMECs under hypoxic conditions and thus were potential downstream genes. Significant decreases in CNV leakage and CNV lesion area, as assessed by fundus fluorescein angiography (FFA) and immunofluorescence of choroidal flat mounts, respectively, were observed in a mouse model intravitreally injected with anti-collagen X monoclonal antibody (mAb) compared to the controls. In conclusion, COL10A1 promotes CNV formation and may represent a new candidate target for the treatment and diagnosis of nAMD and other neovascular diseases.

Protection of Aronia melanocarpa Fruit Extract from Sodium-Iodate-Induced Damages in Rat Retina

Age-related macular degeneration (AMD) is one of the major causes of blindness in elderly populations. However, the dry form of AMD has lack of effective treatments. The fruits of Aronia melanocarpa are rich in anthocyanins. In this study, the protective effects of aronia fruit extract on rat retina were investigated using a NaIO3-induced dry AMD model. Full-field electroretinograms (ERGs) showed that b-wave amplitudes were significantly decreased and the retina structures were disordered in the model. The extract treatment alleviated the injuries. The b-wave amplitudes increased 61.5% in Scotopic 0.01ERG, 122.0% in Photopic 3.0ERG, and 106.8% in Photopic 3.0 flicker; the retina structure disorder was improved with the thickness of outer nuclear layer increasing by 44.1%; and the malonaldehyde level was significantly reduced in extract-treated rat retinas compared to the model. The proteomics analysis showed the expressions of five crystallin proteins, α-crystallin A chain, β-crystallin B2, β-crystallin A3, α-crystallin B chain, and γ-crystallin S, which protect retina ganglion cells, were increased by 7.38-, 7.74-, 15.30-, 4.86-, and 9.14-fold, respectively, in the extract treatment compared to the control, which was also confirmed by immunoblotting. The results suggest that aronia fruit extract, probably due to its anthocyanins, could protect the rat retina by alleviating oxidative damages and by upregulating the crystallin proteins to protect its nerve system.

Dietary fatty acid intake, plasma fatty acid levels, and the risk of age-related macular degeneration (AMD): a dose-response meta-analysis of prospective cohort studies

PURPOSE

Previous population studies on the associations between dietary fatty acids (FAs), plasma FAs levels, and the risk of age-related macular degeneration (AMD) have yielded inconclusive results. Herein, we conducted a dose-response meta-analysis to quantitatively evaluate the associations between specific type of dietary FAs, plasma FAs on early and advanced AMD risk.

METHODS

PubMed, Web of Science, and EMBASE were systematically searched for observational cohort studies published through May 2020. For highest versus lowest comparison and dose-response analyses, the relative risk (RR) estimates with a 95% confidence interval (CI) were analyzed using random effects model.

RESULTS

11 studies with 167,581 participants were included in the meta-analysis. During the follow-up periods (ranging from 3 to 28 years), 6,318 cases of AMD were recorded. Dietary intake of docosahexaenoic acid (DHA) and eicosatetraenoic acid (EPA) combined (per 1 g/day increment) were found to be negatively associated with early AMD (RR: 0.67, 95% CI [0.51, 0.88]). Each 1 g/day increment of DHA (RR: 0.50, 95% CI [0.32, 0.78]) and EPA (RR: 0.40, 95% CI [0.18, 0.87]) was associated with a 50% and 60% reduction of early AMD risk, respectively. Plasma DHA (RR: 0.72, 95% CI [0.55, 0.95]) and EPA (RR: 0.57, 95% CI [0.40, 0.81]) indicated significant negative relationship with advanced AMD.

CONCLUSION

Increasing dietary intake of ω-3 polyunsaturated fatty acids (PUFAs), specifically DHA and EPA, were associated with a reduced risk of early subtype of AMD, while other types of FAs did not present significant results. Further research is warranted to explore the potential association between dietary FA, plasma FA levels, and advanced subtype of AMD.

Medical Compliance of Fibrate and the Decreased Risk of Age-Related Macular Degeneration in Dyslipidemia-Related Diseases: A Population-Based Cohort Study

The purpose of the current study is to evaluate the incidence of age-related macular degeneration (AMD) in dyslipidemia-related diseases with or without the use of fibrate. Patients were defined as dyslipidemia-related diseases according to the diagnostic code and lab exam arrangement, then the population was divided into those with fibrate application and those without via 1:2 ratios of propensity-score matching. The primary outcome is the development of AMD after dyslipidemia-related diseases by the Cox proportional hazard regression. Besides, the relationship between the medical compliance of fibrate, presented as medical possession ratio (MPR), and the AMD development was also analyzed. A total of 22,917 patients and 45,834 individuals were enrolled in the study and control groups. There were 572 and 1181 events of any AMD development in the study and control groups which showed identical risk of AMD (aHR: 0.94, 95% CI: 0.85–1.04). However, a reduced risk of any AMD was found in those patients reached a baseline MPR more than 20% (aHR: 0.729, 95% CI: 0.599–0.887, p = 0.0016) and overall MPR more than 5% three years after the diagnosis of dyslipidemia-related diseases (aHR: 0.712, 95% CI: 0.557–0.909, p = 0.0065). Besides, a lower risk of dry-AMD was also found in those patients with the above conditions (aHR: 0.736, 95% CI: 0.599–0.906, p = 0.0038 and aHR: 0.721, 95% CI: 0.557–0.934, p = 0.0133, respectively). In conclusion, the use of fibrate with fair initial medical compliance will decrease the incidence of AMD in patients with dyslipidemia-related diseases, especially for the development of dry-AMD.

AGE-RELATED MACULAR DEGENERATION - CURRENT STATE OF THE PROBLEM AND PROPHYLAXIS METHODS

OBJECTIVE

The aim: Analyze the ophthalmic studies on diagnostics and treatment of patients with age-related macular degeneration to optimize diagnostics and management tactics.

PATIENTS AND METHODS

Materials and methods: The analysis of scientific papers due to age-related macular degeneration, vitamin D and its functions from scientometric databases: PubMed, Scopus, Web of Science. The methods were next: systematic approach, analysis, summarization and comparison.

CONCLUSION

Conclusions: Age-related macular degeneration is a chronic, progressive disease among people older than 50 years. Late diagnostics and inappropriate treatment may lead to irreversible central vision loss and social disadaptation. Modern studies on the pathogenesis and treatment of this pathology (that are due to the role of the immune system, antioxidants and microelements) demonstrate the effectiveness and prospects for further development around the world to find new ways to solve this problem.

Red Wine Extract Inhibits VEGF Secretion and Its Signaling Pathway in Retinal ARPE-19 Cells to Potentially Disrupt AMD

Age-related macular degeneration (AMD) is a degenerative disease of the retina where the molecular mechanism involves the production of vascular endothelial growth factor (VEGF), a factor of poor prognosis of the progression of the disease. Previous studies have shown that resveratrol, a polyphenol of grapevines, can prevent VEGF secretion induced by stress from retinal cells. Considering the fundamental role played by VEGF in development and progression of AMD, we investigate the potential effect of red wine extract (RWE) on VEGF secretion and its signaling pathway in human retinal cells ARPE-19. To examine the effect of RWE in ARPE-19, a quantitative and qualitative analysis of the RWE was performed by HPLC MS/MS. We show for the first time that RWE decreased VEGF-A secretion from ARPE-19 cells and its protein expression in concentration-dependent manner. RWE-induced alteration in VEGF-A production is associated with a down of VEGF-receptor 2 (VEGF-R2) protein expression and its phosphorylated intracytoplasmic domain. Subsequently, the activation of kinase pathway is disturbing and RWE prevents the phosphorylation of MEK and ERK 1/2 in human retinal cells ARPE-19. Finally, this study sheds light on the interest that the use of polyphenolic cocktails could represent in a prevention strategy.

Retinoid analogs and polyphenols as potential therapeutics for age-related macular degeneration

IMPACT STATEMENT

Age-related macular degeneration (AMD) is a devastating retinal degenerative disease. Epidemiological reports showed an expected increasing prevalence of AMD in the near future. The only one existing FDA-approved pharmacological treatment involves an anti-vascular endothelial growth factor (VEGF) therapy with serious disadvantages. This limitation emphasizes an alarming need to develop new therapeutic approaches to prevent and treat AMD. In this review, we summarize scientific data unraveling the therapeutic potential of the specific retinoid and natural compounds. The experimental results reported by us and other research groups demonstrated that retinoid analogs and compounds with natural product scaffolds could serve as lead compounds for the development of new therapeutic agents with potential to prevent or slow down the pathogenesis of AMD.

A Multi-Omics Approach Identifies Key Regulatory Pathways Induced by Long-Term Zinc Supplementation in Human Primary Retinal Pigment Epithelium

In age-related macular degeneration (AMD), both systemic and local zinc levels decline. Elevation of zinc in clinical studies delayed the progression to end-stage AMD. However, the molecular pathways underpinning this beneficial effect are not yet identified. In this study, we used differentiated primary human fetal retinal pigment epithelium (RPE) cultures and long-term zinc supplementation to carry out a combined transcriptome, proteome and secretome analysis from three genetically different human donors. After combining significant differences, we identified the complex molecular networks using Database for Annotation, Visualization and Integrated Discovery (DAVID) and Ingenuity Pathway Analysis (IPA). The cell cultures from the three donors showed extensive pigmentation, development of microvilli and basal infoldings and responded to zinc supplementation with an increase in transepithelial electrical resistance (TEER) (apical supplementation: 443.2 ± 79.3%, basal supplementation: 424.9 ± 116.8%, compared to control: 317.5 ± 98.2%). Significant changes were observed in the expression of 1044 genes, 151 cellular proteins and 124 secreted proteins. Gene set enrichment analysis revealed changes in specific molecular pathways related to cell adhesion/polarity, extracellular matrix organization, protein processing/transport, and oxidative stress response by zinc and identified a key upstream regulator effect similar to that of TGFB1.