Wet Age-related Macular Degeneration Patients Research Articles

VEGF and ELAVL1/HuR protein levels are increased in dry and wet AMD patients. A new tile in the pathophysiologic mechanisms underlying RPE degeneration?

Age-related macular degeneration (AMD) is a common retinal pathology characterized by degeneration of macula’s retinal pigment epithelium (RPE) and photoreceptors, visual impairment, or loss. Compared to wet AMD, dry AMD is more common, but lacks cures; therefore, identification of new potential therapeutic targets and treatments is urgent. Increased oxidative stress and declining antioxidant, detoxifying systems contribute to the pathophysiologic mechanisms underlying AMD. The present work shows that the Embryonic Lethal Abnormal Vision-Like 1/Human antigen R (ELAVL1/HuR) and the Vascular Endothelial Growth Factor (VEGF) protein levels are higher in the RPE of both dry and wet AMD patients compared to healthy subjects. Moreover, increased HuR protein levels are detected in the retina, and especially in the RPE layer, of a dry AMD model, the nuclear factor erythroid 2-related factor 2 (Nrf2) / peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α) double knock-out mouse. The crosstalk among Nrf2, HuR and VEGF has been also studied in ARPE-19 cells in basal and stressful conditions related to the AMD context (i.e., oxidative stress, autophagy impairment, Nrf2 deficit), offering new evidence of the mutual influence between Nrf2 and HuR, of the dependence of VEGF expression and secretion by these two factors, and of the increased susceptibility of cells to stressful conditions in Nrf2- or HuR-impaired contexts. Overall, this study shows evidence of the interplay among Nrf2, HuR and VEGF, essential factors for RPE homeostasis, and represents an additional piece in the understanding of the complex pathophysiologic mechanisms underlying AMD.

Factors affecting prognosis and need for anti-vascular endothelial growth factor injections in wet age-related macular degeneration.

To understand factors affecting visual prognosis and the number of intravitreal antivascular endothelial growth factor (anti-VEGF) injections needed to stabilize wet age-related macular degeneration (AMD). In this retrospective cohort, 119 treatment-naïve wet AMD patients were followed for two years. In patients with bilateral disease, the eye with worse best-corrected visual acuity (BCVA) or that received more intravitreal injections was recruited as the study eye. In all visits, BCVA was recorded, ophthalmological examination was performed including macular optical coherence tomography imaging. Twenty health status/lifestyle questions were asked to the patients via phone as potential risk factors. All patients received 3 loading doses of intravitreal bevacizumab injections and received repeat injections of aflibercept or ranibizumab when the eye had a new, active neovascular lesion. Patients who took regular micronutrition had similar visual outcome and injection numbers compared to the ones who did not. Patients with bilateral disease needed less intravitreal injections compared to unilateral AMD patients (p = 0.016) and women on hormone replacement therapy (HRT) required less injections compared to the women who were not (p = 0.024). Female patients had a mean gain of 2.7 letters while male patients lost 3.8 letters (p = 0.038). Wet AMD started at an earlier age in smokers (p = 0.002). Patients with a better education level presented earlier with better BCVA (p = 0.037). HRT and anti-VEGF injections to the fellow eye improved the prognosis of wet AMD, while male patients had slightly worse prognosis. Estrogen's protective effects and potential contribution in wet AMD needs further attention. Retrospectively registered: 2020/0622.

Examining the correlation of lymphangiogenesis biomarkers with clinical condition in Age-Related Macular Degeneration (AMD)

The aim of this study is to investigate the relationship between age-related macular degeneration (AMD) and lymphangiogenesis biomarkers, namely LYVE-1, Podoplanin, VEGF-C, VEGFR-2 and VEGFR-3. This prospective and interventional study includes 30 patients with AMD which may be dry or wet type and 30 controls for whom vitrectomy and phacoemulsification was indicated due to additional pathologies (epiretinal membrane, macular hole, retinal detachment, and cataract). 0.1–0,2 ml of aqueous humor and 0.5–1 ml of vitreous sample was taken during the operations. Before the operations 1 tube serum was also taken. All the lymphangiogenesis biomarkers in the study are examined by ELISA method. LYVE-1 (p = 0.001) and Podoplanin (p = 0.004) levels in the vitreous for the patient group are found to be significantly lower than the control group. Serum (p = 0.019), vitreous (p = 0.001), aqueous (p < 0.001) levels of VEGF-C for the patient group are significantly higher than the control group. VEGF-C/VEGFR-2 (p < 0.001), VEGF-C/VEGFR-3 (p < 0.001) ratios in the vitreous for the patient group are found to be significantly higher than the control group. Especially in wet AMD patients, LYVE-1 level is significantly lower in the vitreous (p = 0.002) and aqueous (p = 0.002) than the control group. In addition, Podoplanin level is observed as significantly lower in the vitreous (p = 0.014) and serum (p = 0.002) in comparison to control group. In the wet AMD group, VEGF-C level in the vitreous (p < 0.001), aqueous (p < 0.001) and serum (p = 0.001) is higher than the control group. The result of this study indicates a valid relationship between the weakening of lymphangiogenesis and the pathophysiology of AMD, especially for the wet type. It is observed that the levels of receptors that bind VEGF-C (VEGFR-2 and VEGFR-3) do not increase at the same rate as VEGF-C to compensate for the increase in VEGF-C. The absence of an increase in VEGFR-3, which is especially necessary for lymphangiogenesis, also suggests that lymphangiogenesis is weakened or decreased in AMD. In the future interventional studies with larger series, examination of lymphangiogenic biomarkers in inflammatory retinal diseases and glaucoma may reveal unexplored details.

MicroRNA expression profiling in tears and blood as predictive biomarkers for anti-VEGF treatment response in wet age-related macular degeneration.

This study aimed to investigate the potential of microRNAs (miRNAs) in tears, blood, and aqueous humor as biomarkers for predicting treatment response in wet age-related macular degeneration (AMD) patients undergoing anti-vascular endothelial growth factor (anti-VEGF) therapy. In a single-center prospective cohort study, treatment-naïve wet AMD patients and age-matched controls were enrolled. Clinical data and miRNA levels (miR-199a-3p, miR-365-3p, miR-200b-3p, miR-195-5p, miR-335-5p, and miR-185-5p) in tears, blood, and aqueous humor were collected. Treatment response was categorized into responders and non-responders based on visual acuity and central subfield thickness. MiRNA levels were quantified using reverse-transcription PCR. Statistical analyses were performed, including ROC analysis, to evaluate predictive accuracy. Dysregulated miRNA profiles were observed in wet AMD tears and blood compared to controls. Specifically, miR-199a-3p, miR-195-5p, and miR-185-5p were upregulated, while miR-200b-3p was downregulated in tears. All six miRNAs were elevated in wet AMD blood samples. Notably, responders showed higher tear expression of miR-195-5p and miR-185-5p. Combining these miRNAs yielded the highest predictive power (AUC = 0.878, p = 0.006) for anti-VEGF responders. Dysregulated miRNA profiles in tears and blood suggest their potential as biomarkers for wet AMD. MiR-195-5p and miR-185-5p in tears demonstrate predictive value for anti-VEGF treatment responders. This study underscores the non-invasive prediction potential of miRNA tear analysis in wet AMD treatment responses.

Cataract surgery in AMD patients

Cataract and age‐related macular degeneration (AMD) are leading causes of visual loss and they occur in the similar age group, thus co‐existence of both diseases is real clinical problem and challenge. Theoretical mechanisms considered to be involved in possible relations between cataract surgery and AMD progression include blue light toxicity and the role of post‐operative inflammation. None of these mechanisms was found to play a role in clinical conditions. Some earlier a recent population‐based studies reported an increased risk of late AMD after cataract surgery; however, this was not confirmed by recent cross‐sectional studies (clinical‐based) from South Korea and Australia. Systematic reviews and meta‐analyses reported a moderate quality of evidence to suggest that VA was better by approximately 7 letters in eyes with AMD that underwent cataract surgery vs. eyes with AMD that did not undergo cataract surgery for up to 12 months after surgery and the same quality of evidence did not find an increased risk of progression to exudative AMD for at least 12 months after surgery. The risks and possible advantages of cataract surgery in visual rehabilitation of wet and dry AMD patients will be discussed.

Protective role of IL-17-producing γδ T cells in a laser-induced choroidal neovascularization mouse model

BackgroundVision loss in patients with wet/exudative age-related macular degeneration (AMD) is associated with choroidal neovascularization (CNV), and AMD is the leading cause of irreversible vision impairment in older adults. Interleukin-17A (IL-17A) is a component of the microenvironment associated with some autoimmune diseases. Previous studies have indicated that wet AMD patients have elevated serum IL-17A levels. However, the effect of IL-17A on AMD progression needs to be better understood. We aimed to investigate the role of IL-17A in a laser-induced CNV mouse model.MethodsWe established a laser-induced CNV mouse model in wild-type (WT) and IL-17A-deficient mice and then evaluated the disease severity of these mice by using fluorescence angiography. We performed enzyme-linked immunosorbent assay (ELISA) and fluorescence-activated cell sorting (FACS) to analyze the levels of IL-17A and to investigate the immune cell populations in the eyes of WT and IL-17A-deficient mice. We used ARPE-19 cells to clarify the effect of IL-17A under oxidative stress.ResultsIn the laser-induced CNV model, the CNV lesions were larger in IL-17A-deficient mice than in WT mice. The numbers of γδ T cells, CD3+CD4+RORγt+ T cells, Treg cells, and neutrophils were decreased and the number of macrophages was increased in the eyes of IL-17A-deficient mice compared with WT mice. In WT mice, IL-17A-producing γδ T-cell numbers increased in a time-dependent manner from day 7 to 28 after laser injury. IL-6 levels increased and IL-10, IL-24, IL-17F, and GM-CSF levels decreased in the eyes of IL-17A-deficient mice after laser injury. In vitro, IL-17A inhibited apoptosis and induced the expression of the antioxidant protein HO-1 in ARPE-19 cells under oxidative stress conditions. IL-17A facilitated the repair of oxidative stress-induced barrier dysfunction in ARPE-19 cells.ConclusionsOur findings provide new insight into the protective effect of IL-17A in a laser-induced CNV model and reveal a novel regulatory role of IL-17A-producing γδ T cells in the ocular microenvironment in wet AMD.

Association between Oral Active-Matrix Metalloproteinase-8 Levels and Subretinal Fibrosis among Wet Age-Related Macular Degeneration Patients

Purpose Periodontitis causes low-grade systemic inflammation and has been associated with elevated active-matrix metalloproteinase (aMMP-8) levels, blood-ocular barrier breakdown and a risk of wet age-related macular degeneration. To assess the association between aMMP-8 levels and macular status among patients with wet age-related macular degeneration (AMD). Methods Patients on anti-VEGF treatment for wet AMD were enrolled for oral aMMP-8 rinse test in Mehiläinen Private Hospital, Helsinki, Finland. Macular status was examined from spectral-domain optical coherence tomography (SD-OCT) scans by a medical retina specialist and aMMP-8 levels were analyzed with chairside point-of-care oral rinse (PerioSafe®) test and real-time quantitated by a dentist using the ORALyzer®- reader with a 10 ng/ml cut-off for aMMP-8 activity. Results Elevated aMMP-8 levels were found in 10 out of 32 patients. Age, gender, anti-VEGF (bevacizumab or aflibercept) distribution, cumulative number of anti-VEGF injections and treatment interval were comparable between patients with aMMP-8 levels below and above the point-of-care level. Macular status differed in regard to aMMP-8 activity; among patients with aMMP-8 levels below the point-of-care subretinal fibrosis was found in 6 out of 22 eyes, whereas among patients with aMMP-8 levels above the point-of-care subretinal fibrosis was found in 8 out of 10 eyes (p = 0.005). Respectively, the mean thickness of subretinal fibrosis at fovea was 19.5 ± 44.1 and 92.3 ± 78.3 µm (p = 0.018). No differences were found in the presence and in the area of geographic atrophy, or fluid distribution, whereas thicknesses of serous pigment epithelial detachment (65.5 ± 99.5 and 12.9 ± 27.9 µm, p = 0.038) and neuroretina (204.2 ± 57.8 µm and 143.0 ± 43.7 µm, p = 0.006) were greater in the eyes of patients with physiological aMMP-8 levels compared to those with elevated aMMP-8 levels. Conclusion Elevated aMMP-8 levels may account for subretinal fibrosis formation in wet AMD.

Association of NLRPs with pathogenesis of dry age-related macular degeneration.

Age-related macular degeneration (AMD) is the leading cause of blindness in the elderly population, and Dry AMD is the most common clinical subtype. However, effective measures for the early diagnosis and treatment of dry AMD have not been proposed. In recent years, NOD-like receptors (NLRs) have received attention in the study of AMD as an important class of pattern recognition receptors. We attempted to elucidate the pathogenesis of NLRs in dry AMD from the perspective of chronic inflammation. This study involved 13 patients with dry AMD, 10 age- and sex-matched normal population without any history of disease and 8 patients with wet AMD as controls. Using RT-qPCR, the mRNA expression levels of NLRs in peripheral blood peripheral blood mononuclear cells (PBMCs) were compared to analyze the statistical differences in the expression contents among the three populations. The relative RNA expression of nucleotide-binding oligomerization-like receptor protein 12 (NLRP12) with negative regulation of inflammation was significantly lower in dry AMD patients than in normal people and wet AMD patients. And NLRX1, which also has an anti-inflammatory effect, was lower in dry AMD patients than in wet AMD patients. However, NLRP3 with proinflammatory effect was significantly expressed in wet AMD. The significant decrease in NLRP12 in dry AMD may become a breakthrough in the study of dry AMD and systemic chronic inflammatory response. However, NLRP3 may have a more important role in wet AMD.

Characterization of Vascular Morphology of Neovascular Age-Related Macular Degeneration by Indocyanine Green Angiography.

Age-related macular degeneration (AMD) is a leading cause of blindness among older individuals, and its prevalence is rapidly increasing due to the aging population. Choroidal neovascularization (CNV) or wet AMD, which accounts for 10%-20% of all AMD cases, is responsible for an alarming 80%-90% of AMD-related blindness. Current anti-VEGF therapies show suboptimal responses in approximately 50% of patients. Resistance to anti-VEGF treatment in CNV patients is often associated with arteriolar CNV, while responders tend to have capillary CNV. While fluorescein angiography (FA) is commonly used to assess leakage patterns in wet AMD patients and animal models, it does not provide information about CNV vascular morphology (arteriolar CNV vs. capillary CNV). This protocol introduces the use of indocyanine green angiography (ICGA) to characterize lesion types in laser-induced CNV mouse models. This method is crucial for investigating the mechanisms and treatment strategies for anti-VEGF resistance in wet AMD. It is recommended to incorporate ICGA alongside FA for comprehensive assessment of both leakage and vascular features of CNV in mechanistic and therapeutic studies.

Increased plasma level of terminal complement complex in AMD patients: potential functional consequences for RPE cells.

Polymorphisms in complement genes are risk-associated for age-related macular degeneration (AMD). Functional analysis revealed a common deficiency to control the alternative complement pathway by risk-associated gene polymorphisms. Thus, we investigated the levels of terminal complement complex (TCC) in the plasma of wet AMD patients with defined genotypes and the impact of the complement activation of their plasma on second-messenger signaling, gene expression, and cytokine/chemokine secretion in retinal pigment epithelium (RPE) cells. Collection of plasma from patients with wet AMD (n = 87: 62% female and 38% male; median age 77 years) and controls (n = 86: 39% female and 61% male; median age 58 years), grouped for risk factor smoking and genetic risk alleles CFH 402HH and ARMS2 rs3750846, determination of TCC levels in the plasma, in vitro analysis on RPE function during exposure to patients' or control plasma as a complement source. Genotyping, measurement of TCC concentrations, ARPE-19 cell culture, Ca2+ imaging, gene expression by qPCR, secretion by multiplex bead analysis of cell culture supernatants. TCC concentration in plasma, intracellular free Ca2+, relative mRNA levels, cytokine secretion. TCC levels in the plasma of AMD patients were five times higher than in non-AMD controls but did not differ in plasma from carriers of the two risk alleles. Complement-evoked Ca2+ elevations in RPE cells differed between patients and controls with a significant correlation between TCC levels and peak amplitudes. Comparing the Ca2+ signals, only between the plasma of smokers and non-smokers, as well as heterozygous (CFH 402YH) and CFH 402HH patients, revealed differences in the late phase. Pre-stimulation with complement patients' plasma led to sensitization for complement reactions by RPE cells. Gene expression for surface molecules protective against TCC and pro-inflammatory cytokines increased after exposure to patients' plasma. Patients' plasma stimulated the secretion of pro-inflammatory cytokines in the RPE. TCC levels were higher in AMD patients but did not depend on genetic risk factors. The Ca2+ responses to patients' plasma as second-messenger represent a shift of RPE cells to a pro-inflammatory phenotype and protection against TCC. We conclude a substantial role of high TCC plasma levels in AMD pathology.

The Effect of Intravitreal Bevacizumab Injection in Wet Age-Related Macular Degeneration Patients with Cataract Surgery

This study was design to evaluate the efficacy of cataract surgery with simultaneous intravitreal bevacizumab injection for wet age-related macular degeneration. Of the patients who underwent anti-vascular endothelial growth factor injections, cataract surgery was performed in 24 eyes (control group), and simultaneous intravitreal bevacizumab injection was performed in 27 eyes (bevacizumab group). Best corrected visual acuity, ocular tonometry, anterior chamber inflammation, and central subfield macular thickness were measured at baseline and 1 week, 1 month, 3 months, and 6 months after surgery. The mean central subfield macular thickness increased 1 month postoperatively in the control group (&lt;i&gt;p&lt;/i&gt; = 0.02), whereas there was no significant change in the bevacizumab group. When the preoperative and postoperative differences between the two groups were compared at each time point, the mean best corrected visual acuity improved in the bevacizumab group at 3 months after surgery (&lt;i&gt;p&lt;/i&gt; = 0.045), and the mean central subfield macular thickness was more decreased in the bevacizumab group at 1 month after surgery compared to that of the control group (&lt;i&gt;p&lt;/i&gt; = 0.032). Additional anti-vascular endothelial growth factor injection was performed after surgery at 1.56 ± 2.05 months and 2.52 ± 2.01 months, in the control and bevacizumab groups, respectively (&lt;i&gt;p&lt;/i&gt; = 0.047). Simultaneous cataract surgery and intravitreal bevacizumab injection is considered an effective treatment since it reduces central subfield macular thickness in the short term, and it can delay the timing of additional anti-vascular endothelial growth factor injections after surgery.

Serum Autoantibodies in Patients with Dry and Wet Age-Related Macular Degeneration

To assess the serum autoantibody profile in patients with dry and exudative age-related macular degeneration compared with healthy volunteers to detect potential biomarkers, e.g., markers for progression of the disease. IgG Immunoreactivities were compared in patients suffering from dry age-related macular degeneration (AMD) (n = 20), patients with treatment-naive exudative AMD (n = 29) and healthy volunteers (n = 21). Serum was analysed by customized antigen microarrays containing 61 antigens. The statistical analysis was performed by univariate and multivariate analysis of variance, predictive data-mining methods and artificial neuronal networks were used to detect specific autoantibody patterns. The immunoreactivities of dry and wet AMD patients were significantly different from each other and from controls. One of the most prominently changed reactivity was against alpha-synuclein (p ≤ 0.0034), which is known from other neurodegenerative diseases. Furthermore, reactivities against glyceraldehyde-3-phosphat-dehydrogenase (p ≤ 0.031) and Annexin V (p ≤ 0.034), which performs a major role in apoptotic processes, were significantly changed. Some immunoreacitvities were antithetic regulated in wet and dry-AMD, such as Vesicle transport-related protein (VTI-B). Comparison of autoantibody profiles in patients with dry and wet AMD revealed significantly altered immunoreactivities against proteins particularly found in immunological diseases, further neurodegenerative, apoptotic and autoimmune markers could be observed. A validation study has to explore if these antibody pattern can help to understand the underlying differences in pathogenesis, evaluate their prognostic value and if those could be possibly useful as additional therapeutic targets.

Ganglion cell complex changes in wet AMD patients treated with anti-VEGF intravitreal injections according to a treat-and-extend protocol

ObjectifAnalyser la variation de l’épaisseur du complexe des cellules ganglionnaires (GCC) dans la dégénérescence maculaire liée à l’âge (DMLA) humide chez des patients qui reçoivent des injections intravitréennes. NatureÉtude de cohorte rétrospective portant sur 46 yeux dans une seule clinique d'ophtalmologie de soins tertiaires. ParticipantsLe groupe « injection » était formé de patients qui présentaient une DMLA humide et qui ont reçu des injections intravitréennes pendant au moins 3 ans dans le cadre d'un régime « traitement-et-extension » : 22 patients ont reçu le ranibizumab et 1 patient, l'aflibercept. Le groupe témoin était formé de patients atteints de DMLA sèche sous seule observation, qui n'ont reçu aucun traitement pendant la même période. L’épaisseur du GCC et l'acuité visuelle ont été notées au départ de même que lors des visites de suivi à 1, à 2 et à 3 ans. RésultatsDans le groupe injection, on a enregistré une tendance non significative vers une diminution de l’épaisseur du GCC au cours des 3 années de suivi (–4,09 ± 8,47 µm; p = 0,09). Toujours dans le groupe injection, l'analyse de corrélation entre le nombre d'injections intravitréennes et l’épaisseur du GCC a mis au jour une tendance non significative vers l'apparition d'un lien direct : un plus grand nombre d'injections était en corrélation avec un GCC relativement plus épais après 3 ans. On n'a pas noté de différence significative au chapitre de l’épaisseur du GCC entre la visite initiale et le suivi à 3 ans dans le groupe témoin. ConclusionsD'après les résultats de notre étude, il ne se produit pas d'amincissement significatif du GCC chez les patients atteints de DMLA humide après un régime « traitement-et-extension » de 3 ans.

Interplay between autophagy and mitochondrial metabolism in retinal pigment epithelium cells obtained by differentiation of induced pluripotent stem cells generated from wet AMD patients

AbstractPurpose: Age‐related macular degeneration (AMD) presents a limited potential of experimental studies on the target tissue from AMD patients. Therefore, it is important to have a reliable experimental model to study AMD pathogenesis. We differentiated induced pluripotent stem cells (PSCs) derived from individuals suffering from wet AMD into retinal pigment epithelium (RPE) cells (iPSCs‐RPE). Impaired autophagy and mitochondrial metabolism are recognized factors of AMD pathogenesis, but the underlined mechanism is not fully known. The aim of this study was to assess mitochondrial metabolism in dependence on autophagy in iPSCs‐RPE derived from wet AMD patients and non‐AMD controls.Methods: Bafilomycin a1 (Baf1) and MG‐132 were used as autophagy inhibitor and inducer, respectively. Expression of autophagy markers were evaluated by RT‐PCR and western blotting. The Seahorse FX test was used to evaluate mitochondrial metabolism with carbonyl cyanide‐p trifluoromethoxyphenylhydrazone (FCCP) to uncouple oxidative respiration.Results: We observed differences between the expression of the autophagy‐related genes MAP1LC3B (Microtubule Associated Protein 1 Light Chain 3 Beta) and SQSTM1 (Sequestosome 1) in RPE cells derived from wet AMD and non‐AMD controls. In addition, differences in the expression of the HSP701A (Heat Shock Protein Family A (Hsp70) Member 1A, chaperone) gene were also observed. Autophagy differentially affected mitochondrial metabolism as evaluated by basal and maximal respiration, ATP production, spare capacity and proton link.Conclusions: Autophagy differentially influences mitochondrial metabolism in iPSCs‐RPE derived from wet AMD and non‐AMD eyes.Acknowledgement: This work was supported by National Science Centre, Poland grant number 2017/27/B/NZ3/00872.

Single nucleotide polymorphisms in pigmentation‐related dopachrome tautomerase and melanocortin‐1 receptor genes are associated with wet age‐related macular degeneration in a Finnish cohort

AbstractPurpose: Melanin in intracellular organelles, melanosomes, protects the retinal pigment epithelium from ultraviolet radiation and oxidative stress (OS). However, despite the role of OS in the development of age‐related macular degeneration (AMD), the effect of pigmentation‐related genes on the risk of AMD onset is unclear.Methods: Finnish wet AMD patients and control subjects were genotyped for selected pigmentation‐related genes. 26 selected variants for tyrosinase (TYR), tyrosinase‐related protein 1 (TYRP1), dopachrome tautomerase (DCT), melanocortin‐1 receptor (MC1R), microphthalmia‐associated transcription factor (MITF), and orthodenticle homeobox‐2 (OTX2) were analysed using the Sequenom iPlex platform (Sequenom, Hamburg, Germany). Binary logistic regression analyses were performed to find genetic associations.Results: An intronic variant rs1407995 (T &gt; C) of the DCT gene and a two base pair deletion variant rs3212351 (AT &gt; del) in the regulatory region of the MC1R gene were associated with wet AMD in a crude recessive model (OR = 3.250, 95% CI = 1.036–10.195, p = 0.043 and OR = 1.714, 95% CI = 1.004–2.924, p = 0.048, respectively). The age‐ and gender‐adjusted recessive model revealed a stronger association of rs1407995 to AMD (OR = 4.514, 95% CI = 1.300–15.669, p = 0.018), whereas rs3212351 was no longer statistically significant (OR = 1.612, 95% CI = 0.923–2.819, p = 0.093).Conclusions: Several mutations in DCT and MC1R genes are known to associate with the blond or red hair phenotype with increasing ratio of red pro‐oxidant pheomelanin to protective brown eumelanin pigments. Furthermore, MC1R has been linked to the regulation of ocular inflammation, another key event in the pathogenesis of AMD. In conclusion, two polymorphisms in genes regulating melanin production and oxidative balance in pigmented cells were observed in a Finnish cohort evoking interest in their role in AMD onset.

Exploring challenges to nutrition intervention adherence using COM-B model among patients with wet age-related macular degeneration: a qualitative study

ObjectivesTo explore challenges to nutrition intervention adherence using the Capability, Opportunity and Motivation-Behaviour (COM-B) model among wet age-related macular degeneration (AMD) patients. These factors should be considered in the development...

Pachychoroid neovasculopathy can mimic wet type age-related macular degeneration

Purposeto determine the percentage of patients with pachychoroid neovasculopathy (PNV) among patients who have been misdiagnosed and treated with wet age-related macular degeneration (AMD).MethodsIn this retrospective cross-sectional study, patients over 55 years old, who were diagnosed with wet AMD, were re-evaluated. All patients were recalled for examination and imaging. Patients with PNV were differentiated form wet AMD based on inclusion and exclusion criteria.ResultsOverall, 120 patients (137 eyes) were recorded with wet AMD in the clinic. Finally, after complete re-evaluation, 94 (106 eyes) and 26 patients (31 eyes) were assigned to the AMD and the PNV group, respectively. Thus, a total of 20% of patients with primary mistake diagnosis of wet AMD, actually had PNV. The mean sub field choroidal thickness (SFCT) in the AMD and PNV groups was 173.8 ± 69 μm and 342 ± 27 μm, respectively. Drusen and pachydrusen were found in 69.9% and 24% of the cases with AMD and PNV, respectively (P = 0.001). The average number of intravitreal injections of anti-VEGF (vascular endothelial growth factor) required in the AMD and PNV groups was about 5 and 3, respectively, which was statistically significant (P-value 0.02).ConclusionThis study revealed that about a one-fifth of wet AMD patients are actually pachychoroid neovasculopathy. These patients were younger and had thicker SFCT, and developed less subretinal scarring. Thus, the disorder must be considered as an important differential diagnosis of AMD-CNV.

Pigment Epithelium-Derived Factor Protects Retinal Neural Cells and Prevents Pathological Angiogenesis in an Ex Vivo Ischemia Model.

Ocular ischemia/hypoxia is a severe problem in ophthalmology that can cause vision impairment and blindness. However, little is known about the changes occurring in the existing fully formed choroidal blood vessels. We developed a new whole organ culture model for ischemia/hypoxia in rat eyes and investigate the effects of pigment epithelium derived factor (PEDF) protein on the eye tissues. The concentration of oxygen within the vitreous was measured in the enucleated rat eyes and living rats. Then, ischemia was mimicked by incubating the freshly enucleated eyes in medium at 4°C for 14 h. Eyes were fixed immediately after enucleation or were intravitreally injected with PEDF protein or with vehicle before incubation. After incubation, light and electron microscopy (EM) as well as Tunel staining was performed. In the living rats, the intravitreal oxygen concentration was on average at 16.4% of the oxygen concentration in the air and did not change throughout the experiment whereas it was ca. 28% at the beginning of the experiment and gradually decreased over time in the enucleated eyes. EM analysis revealed that the shape of the choriocapillaris changed dramatically after 14 h incubation in the enucleated eyes. The endothelial cells made filopodia-like projections into the vessel lumen. They appeared identical to the labyrinth capillaries found in surgically extracted choroidal neovascular membranes from patients with wet age-related macular degeneration (AMD). These filopodia-like projections nearly closed the vessel lumen and showed open gaps between neighboring endothelial cells. PEDF significantly inhibited labyrinth capillary formation and kept the capillary lumen open. The number of TUNEL-positive ganglion cells and inner nuclear layer cells was significantly reduced in the PEDF-treated eyes compared to the vehicle-treated eyes. The structural changes in the chroidal vessels observed under ischemia/hypoxia conditions can mimic early changes in the process of pathological angiogenesis as observed in wet AMD patients. This new model can be used to investigate short-term drug effects on the choriocapillaris after ischemia/hypoxia and it highlighted the potential of PEDF as a promising candidate for treating wet AMD.

The importance of monitoring wet age-related macular degeneration patients during Coronavirus disease 19 pandemic: A retrospective study of assessment of functional and structural outcomes

ObjectivesIntravitreal anti-vascular endothelial growth factor (anti-VEGF) injections are the gold standard treatment for wet age-related macular degeneration (wet AMD). Coronavirus disease 2019 (COVID-19) has led to the cancellation of many scheduled intravitreal anti-VEGF injection visits. We compared the functional and structural visual outcomes of wet AMD patients who did not adhere to their planned intervals (group 1) with those who did (group 2).MethodsWet AMD patients of Swiss Visio Montchoisi and RétinElysée were included. Best-corrected visual acuity (BCVA) and optical coherence tomography (OCT) changes between their first visit after the end of the first national lockdown in Switzerland (27 April 2020, first post-lockdown visit) and their last visit before the beginning of the first national lockdown in Switzerland (13 March 2020, last pre-lockdown visit) were assessed. The BCVA outcome was defined as unfavorable when there was a loss of ≥ 5 ETDRS letters in the first post-lockdown visit compared to the BCVA at last pre-lockdown visit. The OCT outcome was defined as unfavorable when there was an increase in at least one of the parameters, intraretinal fluid (IRF), subretinal fluid (SRF), or pigment epithelial detachment (PED), at the first post-lockdown visit compared to the last pre-lockdown visit.Main resultsGroup 1 (89 patients, 109 eyes) had a 13.41% greater rate of unfavorable BCVA outcomes and a 38.27% greater rate of unfavorable OCT outcomes than group 2 (96 patients, 122 eyes) (P = 0.04, P < 0.0001, respectively). Multivariate analysis showed that the more the patients deviated from their programmed injections and the higher the BCVA pre-lockdown, the higher the rate of unfavorable BCVA outcomes (P = 0.03 and P = 0.02, respectively). OCT outcomes were not a predictive factor for an unfavorable BCVA outcome.ConclusionsThe cancellation of many intravitreal anti-VEGF injection appointments resulted in worse functional and structural outcomes in wet AMD patients. The COVID-19 pandemic led many patients to refrain from their routine intravitreal anti-VEGF injection appointments, allowing us to analyze the role of designated intervals in the treatment of wet AMD. During any future lockdown due to COVID-19 or similar circumstances, continuity of care for wet AMD patients should be maintained.

Simultaneous Release of Aflibercept and Dexamethasone from an Ocular Drug Delivery System

Purpose Intravitreal injections of anti-vascular endothelial growth factors (anti-VEGF) are the current standard of care for patients with choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD). There is a growing subset of patients that does not respond to anti-VEGF monotherapy treatment. Some patients, however, do respond to combination therapy of corticosteroids and anti-VEGF. This treatment requires monthly/bimonthly injections of anti-VEGF and semi-annual injections of corticosteroid. A drug delivery system (DDS) that simultaneously releases multiple drugs could benefit these patients by reducing the number of injections. The purpose of this study was to characterize the simultaneous release of aflibercept and dexamethasone from a biodegradable microparticle- and nanoparticle-hydrogel DDS. Methods Dexamethasone-loaded nanoparticles and aflibercept-loaded microparticles were created using modified single- and double-emulsion techniques, respectively. Then, microparticles and nanoparticles were embedded into a thermoresponsive, biodegradable poly(ethylene glycol)-co-(L-lactic acid) diacrylate (PEG-PLLA-DA)-N-isopropylacrylamide (NIPAAm) hydrogel DDS. Drug release studies and characterization of DDS were conducted with varying doses of microparticles and nanoparticles. Results The combination aflibercept-loaded microparticle- and dexamethasone-loaded nanoparticle- hydrogel (Combo-DDS) achieved a total release time of 224 days. Small decreases were seen in swelling ratio and equilibrium water content for Combo-DDS compared to monotherapy aflibercept-loaded microparticle-hydrogel DDS (AFL-DDS) and monotherapy dexamethasone-loaded nanoparticle-hydrogel DDS (DEX-DDS). Bioactivity of aflibercept was maintained in Combo-DDS compared to AFL-DDS. Conclusions The Combo-DDS was able to extend and control the release of both aflibercept and dexamethasone simultaneously from a single DDS. This may eliminate the need for separate dosing regiments of anti-VEGF and corticosteroids for wet AMD patients.