Uncovering genetic and non-genetic biomarkers specific for exudative age-related macular degeneration: significant association of twelve variants

Ocular Neovascular Conversion and Systemic Bleeding Complications in Patients with Age-Related Macular Degeneration on Anticoagulants

PURPOSE

Conversion to neovascular disease in patients with non-neovascular age-related macular degeneration (AMD) initiated on direct oral anticoagulants (DOACs) compared with matched patients treated with warfarin.

DESIGN

Retrospective cohort study.

PARTICIPANTS

The study included 20 300 patients and 13 387 patients with non-neovascular AMD initiated on DOACs or warfarin, respectively, before propensity score matching (PSM).

METHODS

TriNetX was used to identify patients diagnosed with non-neovascular AMD stratified by treatment with DOACs or warfarin with at least 6 months of follow-up. Propensity score matching was performed to control for baseline demographics and medical comorbidities.

MAIN OUTCOME MEASURES

Relative risk (RR) of developing neovascular AMD, macular hemorrhage (MH), vitreous hemorrhage (VH), and requiring an ocular intervention (intravitreal anti-VEGF therapy or pars plana vitrectomy [PPV]) within 6 months and 1 year. Patients with chronic atrial fibrillation (AF) on anticoagulation were separately evaluated for the same measures within 5 years after initiating therapy.

RESULTS

Treatment with warfarin was associated with a higher risk of developing neovascular AMD at 6 months (RR, 1.24, 95% confidence interval [CI], 1.12-1.39; P < 0.001) and 1 year (RR, 1.26, 95% CI, 1.14-1.40; P < 0.001) when compared with matched patients treated with DOACs. There was an increased risk of requiring intravitreal anti-VEGF therapy (6 months: RR, 1.30; 95% CI, 1.13-1.49; P < 0.001; 1 year: RR, 1.31, 95% CI, 0.72-2.05; P < 0.001) and PPV (6 months: RR, 2.13; 95% CI, 1.16-3.94; P = 0.01; 1 year: RR, 2.29, 95% CI, 1.30-4.05; P = 0.003). Among patients with AMD and AF treated with warfarin, there was an increased risk of ocular complications (neovascular AMD: RR, 1.25; 95% CI, 1.14-1.38; P < 0.001; MH: RR, 1.86; 95% CI, 1.47-2.35; P < 0.001; VH: RR, 2.22; 95% CI, 1.51-3.26; P < 0.001) and need for intravitreal anti-VEGF therapy (RR, 1.34; 95% CI, 1.18-1.52; P < 0.001) over an extended 5-year period. There was no significant difference in the development of major systemic hemorrhagic events between the 2 cohorts over 5 years.

CONCLUSIONS

Patients with non-neovascular AMD treated with warfarin were more likely to develop neovascular disease and require ocular intervention for hemorrhagic complications when compared with matched patients initiated on DOACs.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Innovations in Medicine: Exploring ChatGPT's Impact on Rare Disorder Management

Artificial intelligence (AI) is rapidly transforming the field of medicine, announcing a new era of innovation and efficiency. Among AI programs designed for general use, ChatGPT holds a prominent position, using an innovative language model developed by OpenAI. Thanks to the use of deep learning techniques, ChatGPT stands out as an exceptionally viable tool, renowned for generating human-like responses to queries. Various medical specialties, including rheumatology, oncology, psychiatry, internal medicine, and ophthalmology, have been explored for ChatGPT integration, with pilot studies and trials revealing each field's potential benefits and challenges. However, the field of genetics and genetic counseling, as well as that of rare disorders, represents an area suitable for exploration, with its complex datasets and the need for personalized patient care. In this review, we synthesize the wide range of potential applications for ChatGPT in the medical field, highlighting its benefits and limitations. We pay special attention to rare and genetic disorders, aiming to shed light on the future roles of AI-driven chatbots in healthcare. Our goal is to pave the way for a healthcare system that is more knowledgeable, efficient, and centered around patient needs.

Study protocol on prevalence of non-exudative macular neovascularisation and its contribution to prediction of exudation in fellow eyes with unilateral exudative AMD (EYE-NEON)

PURPOSE

Fellow eyes of patients with unilateral neovascular age-related macular degeneration (nAMD) are at risk of developing macular neovascularisation (MNV). These eyes may first develop subclinical non-exudative MNV (neMNV) before they leak to form exudative MNV (eMNV). The EYE NEON study is a 2-year study aimed at estimating the prevalence and incidence of neMNV and evaluating its role as a predictor for conversion to neovascular AMD.

METHODS

EYE NEON is a multicentre study that will run in retinal clinics across 25 National Health Service with the aim to recruit 800 patients with new onset nAMD in the first eye. The fellow-eye with no evidence of nAMD at baseline will be the study eye. All study eyes will have OCT and OCTA done at first and second year following first anti-VEGF treatment to the first eye (non-study eye), with new onset nAMD. We will estimate the prevalence and incidence of neMNV over 2 years, rate of conversion from neMNV to eMNV and numbers initiated on treatment for neovascular AMD in the study eye will be reported. Predictive models of conversion including neMNV with other demographic and imaging parameters will be developed.

CONCLUSION

The study design with proposed target sample size is sufficient to evaluate the retinal imaging characteristics of the study eyes with and without neMNV and develop predictive models to inform risk of conversion to nAMD.

Molecular Genetic Mechanisms in Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is among the leading causes of irreversible blindness worldwide. In addition to environmental risk factors, such as tobacco use and diet, genetic background has long been established as a major risk factor for the development of AMD. However, our ability to predict disease risk and personalize treatment remains limited by our nascent understanding of the molecular mechanisms underlying AMD pathogenesis. Research into the molecular genetics of AMD over the past two decades has uncovered 52 independent gene variants and 34 independent loci that are implicated in the development of AMD, accounting for over half of the genetic risk. This research has helped delineate at least five major pathways that may be disrupted in the pathogenesis of AMD: the complement system, extracellular matrix remodeling, lipid metabolism, angiogenesis, and oxidative stress response. This review surveys our current understanding of each of these disease mechanisms, in turn, along with their associated pathogenic gene variants. Continued research into the molecular genetics of AMD holds great promise for the development of precision-targeted, personalized therapies that bring us closer to a cure for this debilitating disease.

WARE: Wet AMD Risk-Evaluation Tool as a Clinical Decision-Support System Integrating Genetic and Non-Genetic Factors

Given the multifactorial features characterizing age-related macular degeneration (AMD), the availability of a tool able to provide the individual risk profile is extremely helpful for personalizing the follow-up and treatment protocols of patients. To this purpose, we developed an open-source computational tool named WARE (Wet AMD Risk Evaluation), able to assess the individual risk profile for wet AMD based on genetic and non-genetic factors. In particular, the tool uses genetic risk measures normalized for their relative frequencies in the general population and disease prevalence. WARE is characterized by a user-friendly web page interface that is intended to assist clinicians in reporting risk assessment upon patient evaluation. When using the tool, plots of population risk distribution highlight a “low-risk zone” and a “high-risk zone” into which subjects can fall depending on their risk-assessment result. WARE represents a reliable population-specific computational system for wet AMD risk evaluation that can be exploited to promote preventive actions and personalized medicine approach for affected patients or at-risk individuals. This tool can be suitable to compute the disease risk adjusted to different populations considering their specific genetic factors and related frequencies, non-genetic factors, and the disease prevalence.

Genetic associations of anti-vascular endothelial growth factor therapy response in age-related macular degeneration: a systematic review and meta-analysis

PURPOSE

To investigate the association of all reported common polymorphisms in anti-vascular endothelial growth factor (VEGF) therapy response and to identify potential clinically useful biomarkers for anti-VEGF therapy response in patients with age-related macular degeneration (AMD).

METHODS

We searched the Embase, PubMed, Web of Science databases in English and the China National Knowledge Infrastructure, WanFang and VIP databases in Chinese for pharmacogenetics studies on anti-VEGF therapy response in AMD. Odds ratios with 95% confidence intervals were calculated using the random effects model.

RESULTS

Among the 10 468 records yielded by the literature search, 33 articles that met the eligibility criteria were included in the meta-analysis. Nine single-nucleotide polymorphisms (SNP) in four genes were observed to be associated with the anti-VEGF therapy response in AMD patients. That is, rs1120063 in the HTRA1 gene; rs10490924 in the age-related maculopathy susceptibility (ARMS2) gene; rs1061170 in the complement factor H (CFH) gene; and rs323085 in the OR52B4 gene were associated with good anti-VEGF therapy responses, while rs800292, rs1410996 and rs1329428 in the CFH gene and rs4910623 and rs10158937 in the OR52B4 gene were associated with poor anti-VEGF therapy response in the AMD patients in our sample.

CONCLUSION

In this study, nine SNPs of four genes were indicated to be significantly associated with the anti-VEGF therapy response in the samples: rs11200638 in the HTRA1 gene; rs10490924 in the ARMS2 gene; rs1061170, rs800292, rs1410996 and rs1329428 in the CFH gene; and rs323085, rs4910623 and rs10158937 in the OR52B4 gene. Further studies based on various ethnicities and large sample sizes are warranted to strengthen the evidence found in the present study.

Predictive Biomarkers of Age-Related Macular Degeneration Response to Anti-VEGF Treatment

Age-related macular degeneration (AMD) is an incurable disease associated with aging that destroys sharp and central vision. Increasing evidence implicates both systemic and local inflammation in the pathogenesis of AMD. Intravitreal injection of anti-vascular endothelial growth factor (VEGF) agents is currently the first-line therapy for choroidal neovascularization in AMD patients. However, a high number of patients do not show satisfactory responses to anti-VEGF treatment after three injections. Predictive treatment response models are one of the most powerful tools for personalized medicine. Therefore, the application of these models is very helpful to predict the optimal treatment for an early application on each patient. We analyzed the transcriptome of peripheral blood mononuclear cells (PBMCs) from AMD patients before treatment to identify biomarkers of response to ranibizumab. A classification model comprised of four mRNAs and one miRNA isolated from PBMCs was able to predict the response to ranibizumab with high accuracy (Area Under the Curve of the Receiver Operating Characteristic curve = 0.968), before treatment. We consider that our classification model, based on mRNA and miRNA from PBMCs allows a robust prediction of patients with insufficient response to anti-VEGF treatment. In addition, it could be used in combination with other methods, such as specific baseline characteristics, to identify patients with poor response to anti-VEGF treatment to establish patient-specific treatment plans at the first visit.

Epigenomic signatures in age-related macular degeneration: Focus on their role as disease modifiers and therapeutic targets

Epigenetics is characterized by molecular modifications able to shape gene expression profiles in response to inner and external stimuli. Therefore, epigenetic elements are able to provide intriguing and useful information for the comprehension and management of different human conditions, including aging process, and diseases. On this subject, Age-related Macular Degeneration (AMD) represents one of the most frequent age-related disorders, dramatically affecting the quality of life of older adults worldwide. The etiopathogenesis is characterized by an interplay among multiple genetic and non-genetic factors, which have been extensively studied. Nevertheless, a deeper dissection of molecular machinery associated with risk, onset, progression and effectiveness of therapies is still missing. In this regard, epigenetic signals may be further explored to disentangle disease etiopathogenesis, the possible therapeutic avenues and the differential response to AMD treatment. This review will discuss the epigenomic signatures mostly investigated in AMD, which could be applied to improve the knowledge of disease mechanisms and to set-up novel or modified treatment options.

Characterization of a natural variant of human NDP52 and its functional consequences on mitophagy

The role of mitophagy, a process that allows the removal of damaged mitochondria from cells, remains unknown in multiple sclerosis (MS), a disease that is found associated with dysfunctional mitochondria. Here we have qualitatively and quantitatively studied the main players in PINK1-mediated mitophagy in peripheral blood mononuclear cells (PBMCs) of patients with relapsing-remitting MS. We found the variant c.491G>A (rs550510, p.G140E) of NDP52, one of the major mitophagy receptor genes, associated with a MS cohort. Through the characterization of this variant, we discovered that the residue 140 of human NDP52 is a crucial modulator of NDP52/LC3C binding, promoting the formation of autophagosomes in order to drive efficient mitophagy. In addition, we found that in the PBMC population, NDP52 is mainly expressed in B cells and by ensuring efficient mitophagy, it is able to limit the production of the proinflammatory cytokine TNF-α following cell stimulation. In sum, our results contribute to a better understanding of the role of NDP52 in mitophagy and underline, for the first time, a possible role of NDP52 in MS.

Associations of TLR4 and IL-8 genes polymorphisms with age-related macular degeneration (AMD): a systematic review and meta-analysis

BACKGROUND

The results of different studies have indicated the possible associations of TLR4 and IL-8 genes polymorphisms with Age-related Macular Degeneration (AMD). A meta-analysis study was designed to evaluate the possible associations of TLR4 (rs4986790/c.896A>G and rs4986791/ c.1196 C > T) and IL-8 (rs4073/c.251A>T and rs2227306/c.781 C > T) genes polymorphisms with AMD.

METHOD

A systematic literature search was carried out in PubMed, Embase, Web of Science, and Scopus databases to identify relevant publications. Pooled Odds Ratio (OR) with 95% Confidence Interval (CI) was used to evaluate the power of association.

RESULTS

A total of 12 case-control studies with 4804 AMD patients and 4422 healthy controls were included in this meta-analysis. The analysis of genotypic and allelic models demonstrated significant associations between IL-8 c.781 C > T (CC vs. TT+TC: OR = 0.62 [0.48-0.81], P < .01; CC vs. TC: OR = 0.65 [0.48-0.89], P < .01; TT vs. CC: OR = 1.64 [1.04-2.57], P = .03; and C vs. T: OR = 0.71 [0.65-0.79], P < .01) and risk of AMD, which all of them passed Bonferroni correction for multiple testing (P-value≤0.01), except for TT vs. CC model. In addition, we found associations under the genotypic model of TLR4 c.896A>G (AA vs. AG+GG: OR = 0.73 [0.55-0.97], P = .03; and AA vs. AG: OR = 0.71 [0.53-0.95], P = .02) although after Bonferroni correction (P'-value<0.02) none of these associations remained significant. However, the data from this meta-analysis declined the associations of TLR4 c.1196 C > T and IL-8 c.251A>T polymorphisms with AMD.

CONCLUSION

The current meta-analysis study suggested that IL-8 c.781 C > T polymorphism is associated with susceptibility to AMD.

Sleeping pattern and activities of daily living modulate protein expression in AMD

Degeneration of macular photoreceptors is a prominent characteristic of age-related macular degeneration (AMD) which leads to devastating and irreversible vision loss in the elderly population. In this exploratory study, the contribution of environmental factors on the progression of AMD pathology by probing the expression of candidate proteins was analyzed. Four hundred and sixty four participants were recruited in the study comprising of AMD (n = 277) and controls (n = 187). Genetics related data was analyzed to demonstrate the activities of daily living (ADL) by using regression analysis and statistical modeling, including contrast estimate, multinomial regression analysis in AMD progression. Regression analysis revealed contribution of smoking, alcohol, and sleeping hours on AMD by altered expression of IER-3, HTRA1, B3GALTL, LIPC and TIMP3 as compared to normal levels. Contrast estimate supports the gender polarization phenomenon in AMD by significant decreased expression of SLC16A8 and LIPC in control population which was found to be unaltered in AMD patients. The smoking, food habits and duration of night sleeping hours also contributed in AMD progression as evident from multinomial regression analysis. Predicted model (prediction estimate = 86.7%) also indicated the crucial role of night sleeping hours along with the decreased expression of TIMP-3, IER3 and SLC16A8. Results revealed an unambiguous role of environmental factors in AMD progression mediated by various regulatory proteins which might result in intermittent AMD phenotypes and possibly influence the outcome of anti-VEGF treatment.

Genetic Determinants Highlight the Existence of Shared Etiopathogenetic Mechanisms Characterizing Age-Related Macular Degeneration and Neurodegenerative Disorders

Age-related macular degeneration (AMD) showed several processes and risk factors in common with neurodegenerative disorders (NDDs). The present work explored the existence of genetic determinants associated with AMD, which may provide insightful clues concerning its relationship with NDDs and their possible application into the clinical practice. In this study, 400 AMD patients were subjected to the genotyping analysis of 120 genetic variants by OpenArray technology. As the reference group, 503 samples representative of the European general population were utilized. Statistical analysis revealed the association of 23 single-nucleotide polymorphisms (SNPs) with AMD risk. The analysis of epistatic effects revealed that ARMS2, IL6, APOE, and IL2RA could contribute to AMD and neurodegenerative processes by synergistic modulation of the expression of disease-relevant genes. In addition, the bioinformatic analysis of the associated miRNA variants highlighted miR-196a, miR-6796, miR-6499, miR-6810, miR-499, and miR-7854 as potential candidates for counteracting AMD and neurodegenerative processes. Finally, this work highlighted the existence of shared disease mechanisms (oxidative stress, immune-inflammatory response, mitochondrial dysfunction, axonal guidance pathway, and synaptogenesis) between AMD and NDDs and described the associated SNPs as candidate biomarkers for developing novel strategies for early diagnosis, monitoring, and treatment of such disorders in a progressive aging population.

CURRENT CONCEPTS AND MODALITIES FOR MONITORING THE FELLOW EYE IN NEOVASCULAR AGE-RELATED MACULAR DEGENERATION: An Expert Panel Consensus

Neovascular age-related macular degeneration in one eye is a major risk factor for developing neovascular age-related macular degeneration in the fellow eye; effective monitoring is therefore critical. This review summarizes existing and developing methods to monitor the fellow eye of patients with unilateral neovascular age-related macular degeneration and provides guidance for patients and clinicians.

The presence of neovascular age-related macular degeneration (nAMD) in one eye is a major risk factor for the development of disease in the fellow eye. Several methods exist to help physicians monitor the fellow eye, with new technologies becoming increasingly available.

Overview of the molecular determinants contributing to the expression of Psoriasis and Psoriatic Arthritis phenotypes

Psoriasis and psoriatic arthritis are multifactorial chronic disorders whose etiopathogenesis essentially derives from the alteration of several signalling pathways and the co-occurrence of genetic, epigenetic and non-genetic susceptibility factors that altogether affect the functional and structural property of the skin. Although shared and differential susceptibility genes and molecular pathways are known to contribute to the onset of pathological phenotypes, further research is needed to dissect the molecular causes of psoriatic disease and its progression towards Psoriatic Arthritis. This review will therefore be addressed to explore differences and similarities in the etiopathogenesis and progression of both disorders, with a particular focus on genes involved in the maintenance of the skin structure and integrity (keratins and collagens), modulation of patterns of recognition (through Toll-like receptors and dectin-1) and immuno-inflammatory response (by NLRP3-dependent inflammasome) to microbial pathogens. In addition, special emphasis will be given to the contribution of epigenetic elements (methylation pattern, non-coding RNAs, chromatin modifiers and 3D genome organization) to the etiopathogenesis and progression of psoriasis and psoriatic arthritis. The evidence discussed in this review highlights how the knowledge of patients' clinical and (epi)genomic make-up could be helpful for improving the available therapeutic strategies for psoriasis and psoriatic arthritis treatment.

Dietary and Lifestyle Factors Modulate the Activity of the Endogenous Antioxidant System in Patients with Age-Related Macular Degeneration: Correlations with Disease Severity

Age-related macular degeneration (AMD) is a common cause of blindness in the elderly population, but the pathogenesis of this disease remains largely unknown. Since oxidative stress is suggested to play a major role in AMD, we aimed to assess the activity levels of components of the antioxidant system in patients with AMD. We also investigated whether lifestyle and dietary factors modulate the activity of these endogenous antioxidants and clinical parameters of disease severity. We recruited 330 patients with AMD (39 with early, 100 with intermediate and 191 with late form of AMD) and 121 controls in this study. At enrolment, patients' dietary habits and physical activity were assessed, and each study participant underwent a thorough ophthalmologic examination. The activity of several components of the antioxidant system were measured in red blood cells and platelets using both kinetic and spectrophotometric methods. Patients with AMD consumed much lower levels of fatty fish and eggs than the control group (p = 0.008 and p = 0.04, respectively). In the nAMD group, visual acuity (VA) correlated positively with green vegetable consumption (Rs = +0.24, p = 0.004) and omega-3-rich oil intake (Rs = +0.17, p = 0.03). In the AMD group, the total physical activity MET score correlated positively with VA (Rs = +0.17, p = 0.003) and correlated negatively with the severity of AMD (Rs = -0.14, p = 0.01). A multivariate analysis of patients and controls adjusted for age, sex, and smoking status (pack-years) revealed that AMD was an independent variable associated with a lower RBC catalase (β = -0.37, p < 0.001) and higher PLT catalase (β = +0.25, p < 0.001), RBC GPx (β = +0.26, p < 0.001), PLT GPx (β = +0.16, p = 0.001), RBC R-GSSG (β = +0.13, p = 0.009), PLT R-GSSG (β = +0.12, p = 0.02) and RBC GSH transferase (β = +0.23, p < 0.001) activity. The activities of components of the antioxidant system were associated with disease severity and depended on dietary habits. The observed substantial increase in the activity of many critical endogenous antioxidants in patients with AMD further indicates that the required equilibrium in the antioxidant system is disturbed throughout the course of the disease. Our findings explicitly show that a diet rich in green vegetables, fish and omega-3-rich oils, supplemented by physical exercise, is beneficial for patients with AMD, as it might delay disease progression and help retain better visual function.

Statistical driver genes as a means to uncover missing heritability for age-related macular degeneration

Background

Age-related macular degeneration (AMD) is a progressive retinal disease contributing to blindness worldwide. Multiple estimates for AMD heritability (h²) exist; however, a substantial proportion of h² is not attributable to known genomic loci. The International AMD Genomics Consortium (IAMDGC) gathered the largest dataset of advanced AMD (ADV) cases and controls available and identified 34 loci containing 52 independent risk variants defining known AMD h². To better define AMD heterogeneity, we used Pathway Analysis by Randomization Incorporating Structure (PARIS) on the IAMDGC data and identified 8 statistical driver genes (SDGs), including 2 novel SDGs not discovered by the IAMDGC. We chose to further investigate these pathway-based risk genes and determine their contribution to ADV h², as well as the differential ADV subtype h².

Methods

We performed genomic-relatedness-based restricted maximum-likelihood (GREML) analyses on ADV, geographic atrophy (GA), and choroidal neovascularization (CNV) subtypes to investigate the h² of genotyped variants on the full DNA array chip, 34 risk loci (n = 2758 common variants), 52 variants from the IAMDGC 2016 GWAS, and the 8 SDGs, specifically the novel 2 SDGs, PPARA and PLCG2.

Results

Via GREML, full chip h² was 44.05% for ADV, 46.37% for GA, and 62.03% for CNV. The lead 52 variants’ h² (ADV: 14.52%, GA: 8.02%, CNV: 13.62%) and 34 loci h² (ADV: 13.73%, GA: 8.81%, CNV: 12.89%) indicate that known variants contribute ~ 14% to ADV h². SDG variants account for a small percentage of ADV, GA, and CNV heritability, but estimates based on the combination of SDGs and the 34 known loci are similar to those calculated for known loci alone. We identified modest epistatic interactions among variants in the 2 SDGs and the 52 IAMDGC variants, including modest interactions between variants in PPARA and PLCG2.

Conclusions

Pathway analyses, which leverage biological relationships among genes in a pathway, may be useful in identifying additional loci that contribute to the heritability of complex disorders in a non-additive manner. Heritability analyses of these loci, especially amongst disease subtypes, may provide clues to the importance of specific genes to the genetic architecture of AMD.

Further understanding of epigenetic dysfunction of the retinal pigment epithelium in AMD

Introduction

Modulation of epigenetic mechanisms that contribute to retinal development may render the eye susceptible to age-related macular degeneration (AMD). Progression of AMD involves alterations of epigenome such as CpG methylation and histone modifications, and study of the epigenetic regulation of molecular/ cellular pathways associated with AMD might identify target epigenetic markers for treatment of AMD.

Areas covered

In this review, we provide an overview of the influence of epigenetic factors on signaling pathways/ related genes associated with AMD, mainly hypoxia, angiogenesis, inflammation, complement, and oxidative stress; and discuss the critical role of microRNAs in AMD.

Expert Opinion

Better understanding of epigenetic-mediated and microRNA-mediated regulation of the AMD disease-related pathways would help to assess the risk of developing AMD besides providing valuable insight on potential target candidates for AMD therapy.

Shared (epi)genomic background connecting neurodegenerative diseases and type 2 diabetes

The progressive aging of populations has resulted in an increased prevalence of chronic pathologies, especially of metabolic, neurodegenerative and movement disorders. In particular, type 2 diabetes (T2D), Alzheimer’s disease (AD) and Parkinson’s disease (PD) are among the most prevalent age-related, multifactorial pathologies that deserve particular attention, given their dramatic impact on patient quality of life, their economic and social burden as well the etiopathogenetic mechanisms, which may overlap in some cases. Indeed, the existence of common triggering factors reflects the contribution of mutual genetic, epigenetic and environmental features in the etiopathogenetic mechanisms underlying T2D and AD/PD. On this subject, this review will summarize the shared (epi)genomic features that characterize these complex pathologies. In particular, genetic variants and gene expression profiles associated with T2D and AD/PD will be discussed as possible contributors to determine the susceptibility and progression to these disorders. Moreover, potential shared epigenetic modifications and factors among T2D, AD and PD will also be illustrated. Overall, this review shows that findings from genomic studies still deserves further research to evaluate and identify genetic factors that directly contribute to the shared etiopathogenesis. Moreover, a common epigenetic background still needs to be investigated and characterized. The evidences discussed in this review underline the importance of integrating large-scale (epi)genomic data with additional molecular information and clinical and social background in order to finely dissect the complex etiopathogenic networks that build up the “disease interactome” characterizing T2D, AD and PD.

Association of combined complement factor H Y402H and ARMS2/LOC387715 A69S polymorphisms with age-related macular degeneration: an updated meta-analysis

BACKGROUND

Complement factor H (CFH) Y402 H (rs1061170) and age-related maculopathy susceptibility2 (ARMS2)/LOC387715 A69 S (rs10490924) polymorphisms shown to have significant association with AMD. In this meta-analysis, we updated and pooled the results of available association studies between combined ARMS2/LOC387715A69 S-CFHY402 H genotypes and AMD to estimate the synergistic effects.

METHODS

Heterogeneity of studies was evaluated using Cochran Q-test and I-square index. To modify the heterogeneity in the variables we used random effects model. Meta-analysis was performed using STATA. To estimate the additive or supra-additive effects we calculated RERI (relative excess risk due to interaction), AP (attributable proportion due to interaction), S (synergy index) and V (multiplicative index).

RESULTS

We included 12 studies with 4668 AMD patients and 4936 control subjects. Considering the GGTT genotypes as reference line, the pooled AMD odds ratios for stratified combined genotypes was 2.13 (95% CI 1.64-2.78) for GGnonTT, 2.17 (95% CI 1.63-2.89) for nonGGTT and 7.23 (95% CI 4.95-10.55) for nonGGnonTT. Pooled synergy analysis revealed RERI = 3.90 (95% CI 0.58-10.03), AP = .53 (95% CI 0.09-0.69), S = 2.57 (95% CI 1.27-5.22) and V = 1.47 (95% CI 1.21-1.80).

CONCLUSION

This updated analysis showed a strong synergistic and positive multiplicative effect of these two genes indicating that there is common pathway of ARMS2/LOC387715 A69 S and CFH Y402 H in AMD pathogenesis which may be complement system pathway.

RNAseq-Based Prioritization Revealed COL6A5, COL8A1, COL10A1 and MIR146A as Common and Differential Susceptibility Biomarkers for Psoriasis and Psoriatic Arthritis: Confirmation from Genotyping Analysis of 1417 Italian Subjects

Psoriasis (Ps) and Psoriatic Arthritis (PsA) are characterized by a multifactorial etiology, involving genetic and environmental factors. The present study aimed to investigate polymorphisms (SNPs) within genes involved in extracellular matrix and cell homeostasis and microRNA genes as susceptibility biomarkers for Ps and PsA. Bioinformatic analysis on public RNA-seq data allowed for selection of rs12488457 (A/C, COL6A5), rs13081855 (G/T, COL8A1), rs3812111 (A/T, COL10A1) and rs2910164 (C/G, MIR146A) as candidate biomarkers. These polymorphisms were analyzed by Real-Time PCR in a cohort of 1417 Italian patients (393 Ps, 424 PsA, 600 controls). Statistical and bioinformatic tools were utilized for assessing the genetic association and predicting the effects of the selected SNPs. rs12488457, rs13081855 and rs2910164 were significantly associated with both Ps (p = 1.39 × 10⁻⁸, p = 4.52 × 10⁻⁴, p = 0.04, respectively) and PsA (p = 5.12 × 10⁻⁵, p = 1.19 × 10⁻⁶, p = 0.01, respectively). rs3812111, instead, was associated only with PsA (p = 0.005). Bioinformatic analysis revealed common and differential biological pathways involved in Ps and PsA. COL6A5 and COL8A1 take part in the proliferation and angiogenic pathways which are altered in Ps/PsA and contribute to inflammation together with MIR146A. On the other hand, the exclusive association of COL10A1 with PsA highlighted the specific involvement of bone metabolism in PsA.

LINC00167 Regulates RPE Differentiation by Targeting the miR-203a-3p/SOCS3 Axis

Increasing evidence has indicated that long non-coding RNAs (lncRNAs) play significant roles in various diseases; however, their roles in age-related macular degeneration (AMD) remain unclear. Dedifferentiation and dysfunction of retinal pigment epithelium (RPE) cells have been shown to contribute to AMD etiology in several studies. Herein, we found that lncRNA LINC00167 was downregulated in RPE-choroid samples of AMD patients and dysfunctional RPE cells, and it was consistently upregulated along with RPE differentiation. In vitro study indicated that reduced endogenous LINC00167 expression resulted in RPE dedifferentiation, which was typified by attenuated expression of RPE markers, reduced vascular endothelial growth factor A secretion, accumulation of mitochondrial reactive oxygen species, and interrupted phagocytic ability. Mechanistically, LINC00167 functioned as a sponge for microRNA miR-203a-3p to restore the expression of the suppressor of cytokine signaling 3 (SOCS3), which further inhibited the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway. Taken together, our study demonstrated that LINC00167 showed a protective role in AMD by maintaining RPE differentiation through the LINC00167/miR-203a-3p/SOCS3 axis and might be a potential therapeutic target for AMD.

Associations of microRNAs, Angiogenesis-Regulating Factors and CFH Y402H Polymorphism-An Attempt to Search for Systemic Biomarkers in Age-Related Macular Degeneration

Age-related macular degeneration (AMD) remains the leading cause of blindness in elderly people, but the pathophysiology of this disease is still largely unknown. We investigated the systemic expression of angiogenesis-regulating growth factors and selected miRNAs known to regulate angiogenesis in AMD patients. We also focused on possible correlations of their expression with the presence of CFH Y402H or ARMS A69S risk variants. A total of 354 AMD patients and 121 controls were enrolled in this study. The levels of angiogenesis-regulating factors were analyzed in plasma samples using Luminex technology. The expression of selected miRNAs was analyzed in peripheral blood plasma using real-time qPCR. The genetic analysis was performed with an Illumina NextSeq500 system. AMD was an independent factor associated with lower levels of angiogenin (β = −0.29, p < 0.001), endostatin (β = −0.18, p < 0.001), FGF-basic (β = −0.18, p < 0.001), PlGF (β = −0.24, p < 0.001), miRNA-21-3p (β = −0.13, p = 0.01) and miRNA-155-5p (β = −0.16, p = 0.002); and with higher levels of FGF-acidic (β = 0.11, p = 0.03), miRNA-23a-3p (β = 0.17, p < 0.001), miRNA-126-5p (β = 0.13, p = 0.009), miRNA-16-5p (β = 0.40, p < 0.001), miRNA-17-3p (β = 0.13, p = 0.01), miRNA-17-5p (β = 0.17, p < 0.001), miRNA-223-3p (β = 0.15, p = 0.004), and miRNA-93 (β = 0.11, p = 0.04). The expression of analyzed miRNA molecules significantly correlated with the levels of tested angiogenesis-regulating factors and clinical parameters in AMD patients, whereas such correlations were not observed in controls. We also found an association between the CFH Y402H polymorphism and miRNA profiles, whereby TT homozygotes showed evidently higher expression of miRNA-16-5p than CC homozygotes or TC heterozygotes (p = 0.0007). Our results suggest that the balance between systemic pro- and anti-angiogenic factors and miRNAs is vital in multifactorial AMD pathogenesis.

Expression of VEGFA-regulating miRNAs and mortality in wet AMD

MicroRNAs (miRNAs) regulate gene expression; many of them act in the retinal pigment epithelium (RPE), and RPE degeneration is known to be a critical factor in age‐related macular degeneration (AMD). Repeated injections with anti‐VEGFA (vascular endothelial growth factor A) are the only effective therapy in wet AMD. We investigated the correlation between the expression of 18 miRNAs involved in the regulation of the VEGFA gene in serum of 76 wet AMD patients and 70 controls. Efficacy of anti‐VEGFA treatment was evaluated by counting the number of injections delivered up to 12 years. In addition, we compared the relative numbers of deaths in patient with AMD and control groups. We observed a decreased expression of miR‐34‐5p, miR‐126‐3p, miR‐145‐5p and miR‐205‐5p in wet AMD patients as compared with controls. These miRNAs are involved in the regulation of angiogenesis, cytoprotection and protein clearance. No miRNA was significantly correlated with the treatment outcome. Wet AMD patients had greater mortality than controls, and their survival was inversely associated with the number of anti‐VEGFA injections per year. No association was observed between miRNA expression and mortality. Our study emphasizes the need to clarify the role of miRNA regulation in AMD pathogenesis.

NGS Analysis for Molecular Diagnosis of Retinitis Pigmentosa (RP): Detection of a Novel Variant in PRPH2 Gene

This work describes the application of NGS for molecular diagnosis of RP in a family with a history of severe hypovision. In particular, the proband received a clinical diagnosis of RP on the basis of medical, instrumental examinations and his family history. The proband was subjected to NGS, utilizing a customized panel including 24 genes associated with RP and other retinal dystrophies. The NGS analysis revealed a novel missense variant (c.668T > A, I223N) in PRPH2 gene, which was investigated by segregation and bioinformatic analysis. The variant is located in the D2 loop domain of PRPH2, which is critical for protein activity. Bioinformatic analysis described the c.668T > A as a likely pathogenic variant. Moreover, a 3D model prediction was performed to better characterize the impact of the variant on the protein, reporting a disruption of the α-helical structures. As a result, the variant protein showed a substantially different conformation with respect to the wild-type PRPH2. The identified variant may therefore affect the oligomerization ability of the D2 loop and, ultimately, hamper PRPH2 proper functioning and localization. In conclusion, PRPH2_c.668T > A provided a molecular explanation of RP symptomatology, highlighting the clinical utility of NGS panels to facilitate genotype-phenotype correlations.

Haplotypes of HTRA1 rs1120638, TIMP3 rs9621532, VEGFA rs833068, CFI rs10033900, ERCC6 rs3793784, and KCTD10 rs56209061 Gene Polymorphisms in Age-Related Macular Degeneration

BACKGROUND

To determine the impact of HTRA1 rs1120638, TIMP3 rs9621532, VEGFA rs833068, CFI rs10033900, ERCC6 rs3793784, and KCTD10 rs56209061 genotypes on the development of age-related macular degeneration (AMD) in the Lithuanian population.

METHODS

A total of 916 subjects were examined: 309 patients with early AMD, 301 patients with exudative AMD, and 306 healthy controls. The genotyping of HTRA1 rs11200638, TIMP3 rs9621532, VEGFA rs833068, CFI rs10033900, ERCC6 rs3793784, and KCTD10 rs56209061 was carried out using the RT-PCR method.

RESULTS

Our study showed that single-nucleotide polymorphisms rs3793784 and rs11200638 were associated with increased odds of early and exudative AMD, and the variant in KCTD10 (rs56209061) was found to be associated with decreased odds of early and exudative AMD development after adjustments for age and gender in early AMD analysis and after adjustments only for age in exudative AMD. The haplotype containing two minor alleles C-A and the G-A haplotype in rs3793784-rs11200638 were statistically significantly associated with an increased risk of exudative AMD development after adjustment for age, while the G-G haplotype showed a protective role against early and exudative AMD and the haplotype C-G in rs3793784-rs11200638 was associated with a decreased risk only of exudative AMD development.

CONCLUSIONS

Our study identified two markers, rs11200638 and rs3793784, as risk factors for early and exudative AMD, and one marker, rs56209061, as a protective factor for early and exudative AMD development. The haplotypes constructed of rs3793784-rs11200638 were found to be associated with AMD development, as well.

Bilateral Retinal Angiomatous Proliferation in a Variant of Retinitis Pigmentosa

PURPOSE

To describe the first case of bilateral retinal angiomatous proliferation (RAP) in a patient with a variant of retinitis pigmentosa (RP).

CASE REPORT

An 85-year-old man with RP presented with visual acuity decrease and metamorphopsia in the left eye (LE). Fundus examination revealed typical signs of RP in both eyes, associated with intraretinal macular hemorrhage in the LE. Multimodal imaging, using Colour fundus Photography, Fluorescein (FA), and Indocyanine Green Angiography (ICGA) as well as Spectral-Domain Optical Coherence Tomography (SD-OCT) and Optical Coherence Tomography Angiography (OCTA), revealed a type 3 neovascular lesion in the involved eye. Genetic testing (NGS analysis) was performed to search for genetic variants correlated with the disease phenotype displayed by the patient. The patient was treated with intravitreal injections of bevacizumab, according to a fixed protocol of bimonthly injections plus a booster dose at second month. After 9 months, he was referred for visual acuity decrease and metamorphopsia in the fellow eye, where SD-OCT/OCTA showed a type 3 neovascular lesion in the right eye (RE). He was scheduled for intravitreal injections of bevacizumab. In both eyes, treatment with intravitreal bevacizumab was successful.

The cGAS/STING pathway: a sensor of senescence-associated DNA damage and trigger of inflammation in early age-related macular degeneration

Age-related macular degeneration (AMD) is the leading cause of irreversible blindness among the elderly. Considering the relatively limited effect of therapy on early AMD, it is important to focus on the pathogenesis of AMD, especially early AMD. Ageing is one of the strongest risk factors for AMD, and analysis of the impact of ageing on AMD development is valuable. Among all the ageing hallmarks, increased DNA damage accumulation is regarded as the beginning of cellular senescence and is related to abnormal expression of inflammatory cytokines, which is called the senescence-associated secretory phenotype (SASP). The exact pathway for DNA damage that triggers senescence-associated hallmarks is poorly understood. Recently, mounting evidence has shown that the cGAS/STING pathway is an important DNA sensor related to proinflammatory factor secretion and is associated with another hallmark of ageing, SASP. Thus, we hypothesized that the cGAS/STING pathway is a vital signalling pathway for early AMD development and that inhibition of STING might be a potential therapeutic strategy for AMD cases.

Imaging, Genetic, and Demographic Factors Associated With Conversion to Neovascular Age-Related Macular Degeneration: Secondary Analysis of a Randomized Clinical Trial

Importance

Risk factors associated with the development of neovascular age-related macular degeneration (AMD) have been identified. However, population size and methods to integrate imaging, genetic, and demographic factors associated with conversion to neovascular AMD are limited, specifically when treatment is administered in 1 eye.

Objective

To determine the imaging, genetic, and demographic factors associated with conversion from nonneovascular to neovascular AMD in fellow eyes.

Design, Setting, and Participants

This post hoc secondary analysis of the 24-month phase 3 multicenter, double-masked, active treatment-controlled HARBOR trial included 686 fellow eyes with nonneovascular AMD at baseline. Imaging features describing the presence, number, extent, density, and relative reflectivity of drusen were automatically extracted from spectral-domain optical coherence tomography scans. Genetic analysis included 34 single-nucleotide polymorphisms. Least absolute shrinkage and selection operator regression was performed to narrow imaging features. Survival analysis and Cox proportional hazards regression were performed to determine the association of the selected imaging features and genetic and demographic factors with conversion to neovascular AMD. Data were collected from November 2016 through October 2017 and analyzed from October 2017 through October 2018.

Exposure

Nonneovascular AMD in the fellow eye.

Main Outcomes and Measures

Features associated with conversion to neovascular AMD. Hazard ratios (HRs) and their 95% CIs were calculated.

Results

Among the 686 fellow eyes included in the analysis (406 [59.2%] women; mean [SD] age, 78.12 [8.28] years), 154 (22.4%) converted to neovascular AMD. Female sex was significantly associated with conversion to neovascular AMD (HR, 1.57; 95% CI, 1.11-2.20; P = .009). After controlling for demographic and treatment effects, drusen area within 3 mm of the fovea (HR, 1.45; 95% CI, 1.24-1.69; HR for 1-SD increase, 1.36 [95% CI, 1.20-1.54]) and mean drusen reflectivity (HR, 3.97; 95% CI, 1.11-14.18; HR for 1-SD increase, 1.32 [95% CI, 1.02-1.71]) were significantly associated with conversion to neovascular AMD. In addition, 1 genetic variant (rs61941274) was found to be associated with conversion to neovascular AMD.

Conclusions and Relevance

Two imaging features (total en face area of drusen restricted to a circular area 3 mm from the fovea and mean drusen reflectivity) and 1 genetic variant (ACAD10 locus) were associated with conversion to neovascular AMD. Drusen characteristics may be associated with conversion to neovascular AMD despite treatment in 1 eye.

Trial Registration

ClinicalTrials.gov identifier: NCT00891735.

RAD51B (rs8017304 and rs2588809), TRIB1 (rs6987702, rs4351379, and rs4351376), COL8A1 (rs13095226), and COL10A1 (rs1064583) Gene Variants with Predisposition to Age-Related Macular Degeneration

Background

Age-related macular degeneration (AMD) is a progressive neurodegenerative disease of a central part of the neural retina (macula) and a leading cause of blindness in elderly people. While it is known that the AMD is a multifactorial disease, genetic factors involved in lipid metabolism, inflammation, and neovascularization are currently being widely studied in genome-wide association studies (GWAS). The aim of our study was to evaluate the impact of new single nucleotide polymorphisms (SNPs) in RAD51B, TRIB1, COL8A1, and COL10A1 genes on AMD development.

Methods

Case-control study involved 254 patients diagnosed with early AMD, 244 patients with exudative AMD, and 942 control subjects. The genotyping of RAD51B (rs8017304 and rs2588809), TRIB1 (rs6987702, rs4351379, and rs4351376), COL8A1 (rs13095226), and COL10A1 (rs1064583) was carried out using TaqMan assays by a real-time polymerase chain reaction (RT-PCR) method.

Results

Statistically significant difference was found in genotype (TT, TC, and CC) distribution of COL8A1 rs13095226 between exudative AMD and control groups (60.2%, 33.6%, and 6.1% vs. 64.9%, 32.3%, and 2.9%, respectively, p = 0.036). Also, comparing with TT+TC, rs13095226 CC genotype was associated with 3.5-fold increased odds of exudative AMD development (OR = 3.540; 95% CI: 1.415-8.856; p = 0.007).

Conclusion

Our study revealed a strong association between a variant in COL8A1 (rs13095226) and exudative AMD development.

Atopic Eczema: Genetic Analysis of COL6A5, COL8A1, and COL10A1 in Mediterranean Populations

To date, the genes associated with susceptibility to Atopic Eczema (AE) are mainly implicated in immunity, inflammation, and maintenance of skin barrier. Little is known about the possible relationship between genes modulating Extra-Cellular Matrix (ECM) and AE etiopathogenesis. In this regard, the primary objective of the present study has been the investigation of susceptibility biomarkers localized within genes encoding collagen proteins. Several studies have shown that polymorphisms within the genes encoding such proteins may generate abnormal connective tissues, making them more susceptible to mechanical stress, loss of epidermal integrity, and aging. We therefore decided to investigate three polymorphisms located in COL6A5, COL8A1, and COL10A1 as potential susceptibility biomarkers for AE in a cohort of 1470 subjects of Mediterranean origin. The genes of interest have been selected considering that the ECM and immune/inflammatory response are strongly dysregulated in AE and other complex disorders. The study confirmed that the susceptibility to AE depends on a complex interaction between latitude, geographical localization, and the differential distribution of genetic variants among populations exposed to similar environmental factors.

The Interplay between miRNA-Related Variants and Age-Related Macular Degeneration: EVIDENCE of Association of MIR146A and MIR27A

The complex interplay among genetic, epigenetic, and environmental variables is the basis for the multifactorial origin of age-related macular degeneration (AMD). Previous results highlighted that single nucleotide polymorphisms (SNPs) of CFH, ARMS2, IL-8, TIMP3, SLC16A8, RAD51B, VEGFA, and COL8A1 were significantly associated with the risk of AMD in the Italian population. Given these data, this study aimed to investigate the impact of SNPs in genes coding for MIR146A, MIR31, MIR23A, MIR27A, MIR20A, and MIR150 on their susceptibility to AMD. Nine-hundred and seventy-six patients with exudative AMD and 1000 controls were subjected to an epigenotyping analysis through real-time PCR and direct sequencing. Biostatistical and bioinformatic analysis was performed to evaluate the association with susceptibility to AMD. These analyses reported that the SNPs rs11671784 (MIR27A, G/A) and rs2910164 (MIR146A, C/G) were significantly associated with AMD risk. Interestingly, the bioinformatic analysis showed that MIR27A and MIR146A take part in the angiogenic and inflammatory pathways underlying AMD etiopathogenesis. Thus, polymorphisms within the pre-miRNA sequences are likely to affect their functional activity, especially the interaction with specific targets. Therefore, our study represents a step forward in the comprehension of the mechanisms leading to AMD onset and progression, which certainly include the involvement of epigenetic modifications.

Increased soluble urokinase plasminogen activator receptor (suPAR) levels in neovascular age-related macular degeneration: a role for inflammation in the pathogenesis of the disease?

PURPOSE

To evaluate the plasma concentration of the soluble form of the urokinase-type plasminogen activator receptor ((s)uPAR), an established biomarker of chronic inflammation, in patients affected by neovascular age-related macular degeneration.

METHODS

Forty consecutive patients affected by age-related macular degeneration and 52 subjects with no history of the disease were included in this case-control study. The two groups of individuals considered for the study were matched for age, sex, and class of medications taken. Plasma concentration of suPAR was measured using a specific ELISA assay (suPARnostic, Birkeroed, Denmark).

RESULTS

The case and control groups were similar for age, gender distribution, weight, height, and systolic and diastolic blood pressure, as well as for dyslipidemia and high blood pressure medication (P > 0.28). The plasma concentrations of suPAR were significantly increased in patients with neovascular age-related macular degeneration when compared to controls (6.19 ± 2.2 ng/ml, vs 5.21 ± 1.5, respectively, mean ± SD P = 0.01).

CONCLUSIONS

Patients with neovascular age-related macular degeneration display increased plasma levels of suPAR, suggesting that chronic inflammation may be involved in the pathogenesis of the disease.

Application of Precision Medicine in Neurodegenerative Diseases

One of the main challenges for healthcare systems is the increasing prevalence of neurodegenerative pathologies together with the rapidly aging populations. The enormous progresses made in the field of biomedical research and informatics have been crucial for improving the knowledge of how genes, epigenetic modifications, aging, nutrition, drugs and microbiome impact health and disease. In fact, the availability of high technology and computational facilities for large-scale analysis enabled a deeper investigation of neurodegenerative disorders, providing a more comprehensive overview of disease and encouraging the development of a precision medicine approach for these pathologies. On this subject, the creation of collaborative networks among medical centers, research institutes and highly qualified specialists can be decisive for moving the precision medicine from the bench to the bedside. To this purpose, the present review has been thought to discuss the main components which may be part of precise and personalized treatment programs applied to neurodegenerative disorders. Parkinson Disease will be taken as an example to understand how precision medicine approach can be clinically useful and provide substantial benefit to patients. In this perspective, the realization of web-based networks can be decisive for the implementation of precision medicine strategies across different specialized centers as well as for supporting clinical/therapeutical decisions and promoting a more preventive and participative medicine for neurodegenerative disorders. These collaborative networks are essentially addressed to find innovative, sustainable and effective strategies able to provide optimal and safer therapies, discriminate at risk individuals, identify patients at preclinical or early stage of disease, set-up individualized and preventative strategies for improving prognosis and patient's quality of life.