The gut-eye axis:from brain neurodegenerative diseases to age-related macular degeneration

Age-related macular degeneration is a serious neurodegenerative disease of the retina that significantly impacts vision.Unfortunately,the specific pathogenesis remains unclear,and effective early treatment options are consequently lacking.The microbiome is defined as a large ecosystem of microorganisms living within and coexisting with a host.The intestinal microbiome undergoes dynamic changes owing to age,diet,genetics,and other factors.Such dysregulation of the intestinal flora can disrupt the microecological balance,resulting in immunological and metabolic dysfunction in the host,and affecting the development of many diseases.In recent decades,significant evidence has indicated that the intestinal flora also influences systems outside of the digestive tract,including the brain.Indeed,several studies have demonstrated the critical role of the gut-brain axis in the development of brain neurodegenerative diseases,including Alzheimer’s disease and Parkinson’s disease.Similarly,the role of the“gut-eye axis”has been confirmed to play a role in the pathogenesis of many ocular disorders.Moreover,age-related macular degeneration and many brain neurodegenerative diseases have been shown to share several risk factors and to exhibit comparable etiologies.As such,the intestinal flora may play an important role in age-related macular degeneration.Given the above context,the present review aims to clarify the gut-brain and gut-eye connections,assess the effect of intestinal flora and metabolites on age-related macular degeneration,and identify potential diagnostic markers and therapeutic strategies.Currently,direct research on the role of intestinal flora in age-related macular degeneration is still relatively limited,while studies focusing solely on intestinal flora are insufficient to fully elucidate its functional role in age-related macular degeneration.Organ-on-a-chip technology has shown promise in clarifying the gut-eye interactions,while integrating analysis of the intestinal flora with research on metabolites through metabolomics and other techniques is crucial for understanding their potential mechanisms.

Subretinal fibrosis secondary to neovascular age-related macular degeneration:mechanisms and potential therapeutic targets

Subretinal fibrosis is the end-stage sequelae of neovascular age-related macular degeneration.It causes local damage to photoreceptors,retinal pigment epithelium,and choroidal vessels,which leads to permanent central vision loss of patients with neovascular age-related macular degeneration.The pathogenesis of subretinal fibrosis is complex,and the underlying mechanisms are largely unknown.Therefore,there are no effective treatment options.A thorough understanding of the pathogenesis of subretinal fibrosis and its related mechanisms is important to elucidate its complications and explore potential treatments.The current article reviews several aspects of subretinal fibrosis,including the current understanding on the relationship between neovascular age-related macular degeneration and subretinal fibrosis;multimodal imaging techniques for subretinal fibrosis;animal models for studying subretinal fibrosis;cellular and non-cellular constituents of subretinal fibrosis;pathophysiological mechanisms involved in subretinal fibrosis,such as aging,infiltration of macrophages,different sources of mesenchymal transition to myofibroblast,and activation of complement system and immune cells;and several key molecules and signaling pathways participating in the pathogenesis of subretinal fibrosis,such as vascular endothelial growth factor,connective tissue growth factor,fibroblast growth factor 2,platelet-derived growth factor and platelet-derived growth factor receptor-β,transforming growth factor-βsignaling pathway,Wnt signaling pathway,and the axis of heat shock protein 70-Toll-like receptors 2/4-interleukin-10.This review will improve the understanding of the pathogenesis of subretinal fibrosis,allow the discovery of molecular targets,and explore potential treatments for the management of subretinal fibrosis.

Biomaterial engineering strategies for modeling the Bruch's membrane in age-related macular degeneration

Age-related macular degeneration,a multifactorial inflammatory degenerative retinal disease,ranks as the leading cause of blindness in the elderly.Strikingly,there is a scarcity of curative therapies,especially for the atrophic advanced form of age-related macular degeneration,likely due to the lack of models able to fully recapitulate the native structure of the outer blood retinal barrier,the prime to rget tissue of age-related macular degeneration.Standard in vitro systems rely on 2D monocultures unable to adequately reproduce the structure and function of the outer blood retinal barrier,integrated by the dynamic interaction of the retinal pigment epithelium,the Bruch's membrane,and the underlying choriocapillaris.The Bruch's membrane provides structu ral and mechanical support and regulates the molecular trafficking in the outer blood retinal barrier,and therefo re adequate Bruch's membrane-mimics are key for the development of physiologically relevant models of the outer blood retinal barrie r.In the last years,advances in the field of biomaterial engineering have provided novel approaches to mimic the Bruch's membrane from a variety of materials.This review provides a discussion of the integrated properties and function of outer blood retinal barrier components in healt hy and age-related macular degeneration status to understand the requirements to adequately fabricate Bruch's membrane biomimetic systems.Then,we discuss novel materials and techniques to fabricate Bruch's membrane-like scaffolds for age-related macular degeneration in vitro modeling,discussing their advantages and challenges with a special focus on the potential of Bruch's membrane-like mimics based on decellularized tissue.

NLRP3 and autophagy in retinal ganglion cell inflammation in age-related macular degeneration:potential therapeutic implications

Retinal degenerative diseases were a large group of diseases characterized by the primary death of retinal ganglion cells(RGCs).Recent studies had shown an interaction between autophagy and nucleotide-binding oligomerization domain-like receptor 3(NLRP3)inflammasomes,which may affect RGCs in retinal degenerative diseases.The NLRP3 inflammasome was a protein complex that,upon activation,produces caspase-1,mediating the apoptosis of retinal cells and promoting the occurrence and development of retinal degenerative diseases.Upregulated autophagy could inhibit NLRP3 inflammasome activation,while inhibited autophagy can promote NLRP3 inflammasome activation,which leaded to the accelerated emergence of drusen and lipofuscin deposition under the neurosensory retina.The activated NLRP3 inflammasome could further inhibit autophagy,thus forming a vicious cycle that accelerated the damage and death of RGCs.This review discussed the relationship between NLRP3 inflammasome and autophagy and its effects on RGCs in age-related macular degeneration,providing a new perspective and direction for the treatment of retinal diseases.

HCSP-Net:A Novel Model of Age-Related Macular Degeneration Classification Based on Color Fundus Photography

Age-related macular degeneration(AMD)ranks third among the most common causes of blindness.As the most conventional and direct method for identifying AMD,color fundus photography has become prominent owing to its consistency,ease of use,and good quality in extensive clinical practice.In this study,a convolutional neural network(CSPDarknet53)was combined with a transformer to construct a new hybrid model,HCSP-Net.This hybrid model was employed to tri-classify color fundus photography into the normal macula(NM),dry macular degeneration(DMD),and wet macular degeneration(WMD)based on clinical classification manifestations,thus identifying and resolving AMD as early as possible with color fundus photography.To further enhance the performance of this model,grouped convolution was introduced in this study without significantly increasing the number of parameters.HCSP-Net was validated using an independent test set.The average precision of HCSPNet in the diagnosis of AMD was 99.2%,the recall rate was 98.2%,the F1-Score was 98.7%,the PPV(positive predictive value)was 99.2%,and the NPV(negative predictive value)was 99.6%.Moreover,a knowledge distillation approach was also adopted to develop a lightweight student network(SCSP-Net).The experimental results revealed a noteworthy enhancement in the accuracy of SCSP-Net,rising from 94%to 97%,while remarkably reducing the parameter count to a quarter of HCSP-Net.This attribute positions SCSP-Net as a highly suitable candidate for the deployment of resource-constrained devices,which may provide ophthalmologists with an efficient tool for diagnosing AMD.

Regulatory factors of Nrf2 in age-related macular degeneration pathogenesis

Age-related macular degeneration(AMD)is a complicated disease that causes irreversible visual impairment.Increasing evidences pointed retinal pigment epithelia(RPE)cells as the decisive cell involved in the progress of AMD,and the function of anti-oxidant capacity of PRE plays a fundamental physiological role.Nuclear factor erythroid 2 related factor 2(Nrf2)is a significant transcription factor in the cellular anti-oxidant system as it regulates the expression of multiple anti-oxidative genes.Its functions of protecting RPE cells against oxidative stress(OS)and ensuing physiological changes,including inflammation,mitochondrial damage and autophagy dysregulation,have already been elucidated.Understanding the roles of upstream regulators of Nrf2 could provide further insight to the OS-mediated AMD pathogenesis.For the first time,this review summarized the reported upstream regulators of Nrf2 in AMD pathogenesis,including proteins and miRNAs,and their underlying molecular mechanisms,which may help to find potential targets via regulating the Nrf2 pathway in the future research and further discuss the existing Nrf2 regulators proved to be beneficial in preventing AMD.

Comparative study between swept-source and spectraldomain OCTA for imaging of choroidal neovascularization in age-related macular degeneration

AIM:To compare the dif ferences of choroidal neovascularization(CNV)measurements between sweptsource and spectral-domain optical coherence tomography angiography(SS-OCTA and SD-OCTA)in neovascular agerelated macular degeneration(nAMD)and the imaging reliability of the two devices.METHODS:Prospective comparative study.SS-OCTA and SD-OCTA were used to scan the same eye with the modes of 3×3 and 6×6 mm2 centered on the neovascularization.Only qualified images were chosen and the border of CNV was manually delineated by two graders independently.The area of CNV(ACNV),vascular perfusion density(PD),and vessel length density(VLD)within the delineation were calculated using Image J.The differences of CNV measurements between the two OCTA devices were compared using Bland-Altman analysis.The agreement between the two graders on the measurements of each device was compared using the intraclass correlation coefficient(ICC).RESULTS:A total of 18 patients(22 eyes)with nAMD were included.The measurements of ACNV,PD,and VLD were 7.247±4.586 and 4.901±3.741 mm^(2),43.202±9.636 and 34.904±10.489,6.339±1.228 and 5.908±1.741 mm^(-1) for SS-OCTA and SD-OCTA,respectively.The differences between the two devices were 2.346±3.030 mm^(2)(Z=-3.782,P<0.0001),8.298±14.160(Z=-2.419,P=0.016),and 0.431±2.114 mm^(-1)(Z=-0.828,P=0.408)for ACNV,PD and VLD,respectively.The ICC between two graders were 0.893(P<0.001),0.902(P<0.001),0.885(P<0.001)for ACNV,PD,VLD in SS-OCTA,and 0.971(P<0.001),0.976(P<0.001),0.973(P<0.001)in SD-OCTA,respectively.CONCLUSION:Both OCTA devices have high imaging reliability.Compared with SD-OCTA,SS-OCTA has a larger ACNV measurements,but doesn’t show better resolution of internal vessels of CNV and well signal strength.

Investigating the causal link between gut microbiota and dry age-related macular degeneration:a bidirectional Mendelian randomization study

AIM:To assess the causal link between 211 gut microbiota(GM)taxa and dry age-related macular degeneration(dAMD)risk.METHODS:Mendelian randomization using instrumental factors taken from a genome-wide association study(GWAS)were used.Inverse variance weighted(IVW)analysis and sensitivity analysis were performed on the FinnGen project,which included 5095 cases and 222590 controls.RESULTS:The IVW analysis showed substantial genusand family-level relationships between GM taxa and dAMD risk.Specifically,the family Peptococcaceae(P=0.03),genus Bilophila(P=3.91×10^(-3)),genus Faecalibacterium(P=6.55×10^(-3)),and genus Roseburia(P=0.04)were linked to a higher risk of developing dAMD,while the genus Candidatus Soleaferrea(P=7.75×10^(-4)),genus Desulfovibrio(P=0.04)and genus Eubacterium ventriosum group(P=0.04)exhibited a protective effect against dAMD.No significant causal relationships were observed at higher taxonomic levels.Additionally,in the reverse IVW analysis,no meaningful causal effects of the 7 GM taxa.CONCLUSION:These findings give support for the gutretina axis participation in dAMD and shed light on putative underlying processes.Investigations on the connection between GM and dAMD have not yet revealed the underlying mechanism.

RNA-sequencing expression profile and functional analysis of retinal pigment epithelium in atrophic age-related macular degeneration

The retinal pigment epithelium(RPE)is fundamental to sustaining retinal homeostasis.RPE abnormality leads to visual defects and blindness,including age-related macular degeneration(AMD).Although breakthroughs have been made in the treatment of neovascular AMD,effective intervention for atrophic AMD is largely absent.The adequate knowledge of RPE pathology is hindered by a lack of the patients'RPE datasets,especially at the single-cell resolution.In the current study,we delved into a large-scale single-cell resource of AMD donors,in which RPE cells were occupied in a substantial proportion.Bulk RNA-seq datasets of atrophic AMD were integrated to extract molecular characteristics of RPE in the pathogenesis of atrophic AMD.Both in vivo and in vitro models revealed that carboxypeptidase X,M14 family member 2(CPXM2),was specifically expressed in the RPE cells of atrophic AMD,which might be induced by oxidative stress and involved in the epithelial-mesenchymal transition of RPE cells.Additionally,silencing of CPXM2 inhibited the mesenchymal phenotype of RPE cells in an oxidative stress cell model.Thus,our results demonstrated that CPXM2 played a crucial role in regulating atrophic AMD and might serve as a potential therapeutic target for atrophic AMD.

Nomogram for predicting short-term response to anti-vascular endothelial growth factor treatment in neovascular age-related macular degeneration:An observational study

BACKGROUND Anti-vascular endothelial growth factor(anti-VEGF)therapy is critical for managing neovascular age-related macular degeneration(nAMD),but understanding factors influencing treatment efficacy is essential for optimizing patient outcomes.AIM To identify the risk factors affecting anti-VEGF treatment efficacy in nAMD and develop a predictive model for short-term response.METHODS In this study,65 eyes of exudative AMD patients after anti-VEGF treatment for≥1 mo were observed using optical coherence tomography angiography.Patients were classified into non-responders(n=22)and responders(n=43).Logistic regression was used to determine independent risk factors for treatment response.A predictive model was created using the Akaike Information Criterion,and its performance was assessed with the area under the receiver operating characteristic curve,calibration curves,and decision curve analysis(DCA)with 500 bootstrap re-samples.RESULTS Multivariable logistic regression analysis identified the number of junction voxels[odds ratio=0.997,95%confidence interval(CI):0.993-0.999,P=0.010]as an independent predictor of positive anti-VEGF treatment outcomes.The predictive model incorporating the fractal dimension,number of junction voxels,and longest shortest path,achieved an area under the curve of 0.753(95%CI:0.622-0.873).Calibration curves confirmed a high agreement between predicted and actual outcomes,and DCA validated the model's clinical utility.CONCLUSION The predictive model effectively forecasts 1-mo therapeutic outcomes for nAMD patients undergoing anti-VEGF therapy,enhancing personalized treatment planning.

Insensitivity of PI3K/Akt/GSK3 signaling in peripheral blood mononuclear cells of age-related macular degeneration patients

Our recent studies with cultured retinal pigment epithelium cells suggested that overexpression of interleukin 17 receptor C（IL-17RC）,a phenomenon observed in peripheral blood and chorioretinal tissues with age-related macular degeneration（AMD）,was associated with altered activation of phosphatidylinositide 3-kinase（PI3K）,Akt,and glycogen synthase kinase 3（GSK3）.We wondered whether or not altered PI3 K,Akt,and GSK3 activities could be detected in peripheral blood mononuclear cells（PBMC） obtained from AMD patients.In the patients＇ PBMC,absent or reduced serine-phosphorylation of GSK3α or GSK3β was observed,which was accompanied with increased phosphorylation of GSK3 substrates（e.g.CCAAT enhancer binding protein a,insulin receptor substrate 1,and TAU）,indicative of enhanced GSK3 activation.In addition,decreased protein mass of PI3K85α and tyrosinephosphorylation of PI3K50α was present in PBMC of the AMD patients,suggesting impaired PI3 K activation.Moreover,abnormally lowered molecular weight forms of Akt and GSK3 were detected in PBMC of the AMD patients.These data demonstrate that despite the presence of high levels of IL-17 RC,Wnt-3a and vascular endothelial growth factor,the PI3K/Akt/GSK3 signaling pathway is insensitive to these stimuli in PBMC of the AMD patients.Thus,measurement of PI3K/Akt/GSK3 expression and activity in PBMC may serve as a surrogate biomarker for AMD.

Quantitative Assessment of Foveal Avascular Zone in Patients with Early and Intermediate Nonexudative Age-Related Macular Degeneration Using Optical Coherence Tomography-Angiography

Optical coherence tomography-angiography (OCT-A) is a relatively new non-invasive imaging technique which provides three-dimensional visualization of the retinal and choroidal microvasculature. Recently, OCT-A is widely used in the diagnosis of age-related macular degeneration (AMD). Purpose: To compare 3 quantitative indexes of foveal avascular zone (FAZ)—area (A), perimeter (Pm), and circularity (C) in patients with early and intermediate nonexudative AMD and healthy subjects using OCT-A. Methods: Eighty-nine patients with nonexudative AMD (n = 89 eyes) were enrolled in the study. They were compared with sex- and age-matched control group of 66 healthy subjects (n = 66 eyes). The patients with nonexudative AMD were divided into 2 subgroups—early AMD (n = 42 eyes) and intermediate AMD (n = 47 eyes). All participants underwent OCT-A (3 × 3 mm scans, Cirrus HD-OCT, Angioplex, Carl Zeiss Meditec, Dublin, CA). Results: There was no statistically significant difference in all 3 assessed indexes between the early AMD subgroup and the control group (A ? P = 0.139;Pm ? P = 0.230;and C ? P = 0.191). There was also no statistically significant difference in all 3 assessed indexes between the intermediate AMD subgroup and the control group (A ? P = 0.106, Pm ? P = 0.124, and C ? P = 0.102, respectively). Conclusions: According to our results from the assessment of FAZ in patients with early and intermediate AMD, we hypothesize that macular perfusion remains fairly unchanged in the nonexudative stages of the disease. OCT-A is a reliable technique for visualizing and quantifying FAZ in patients with nonexudative AMD.

Choriocapillaris in non-neovascular age-related macular degeneration as evaluated by optical coherence tomography angiography

Dramatic advances in retinal imaging technology over the last two decades have significantly improved our understanding of the natural history and pathophysiology of non-neovascular age-related macular degeneration(AMD).Currently,aside from micronutrient supplements,there are no proven treatments for non-neovascular or dry AMD.Recently,a number of pharmacological agents have been evaluated or are under evaluation for treatment of patients with end-stage dry AMD manifesting as geographic atrophy(GA).It may preferable,however,to intervene earlier in the disease before the development of irreversible loss of visual function.Earlier intervention would require a more precise understanding of biomarkers which may increase the risk of progression from early and intermediate stages to the late stage of the disease.The development of optical coherence tomography angiography(OCTA)has allowed the layers of the retinal microcirculation and choriocapillaris(CC)to be visualized and quantified.Flow deficits in the CC have been observed to increase with age,particularly centrally,and these flow deficits appear to worsen with development and progression of AMD.As such,OCTA-based CC assessment appears to be a valuable new biomarker in our assessment and risk-stratification of AMD.Alterations in the CC may also provide new insights into the pathophysiology of the disease.Enhancement of choriocapillaris function may also prove to be a target of future therapeutic strategies or as a biomarker to monitor the effectiveness of therapy.As such,CC imaging may be anticipated to be an integral tool in the management of dry AMD.

Clinical Analysis of Erzhi Mingmu Decoction in the Treatment of Non-exudative Age-related Macular Degeneration

OBJECTIVE: To study the effect of Erzhi Mingmu Decoction in the treatment of non-exudative age-related macular degeneration. METHODS: A total of 100 patients with non-exudative age-related macular degeneration admitted to our hospital from May 2017 to May 2018 were selected. They were randomly divided into the study group and the control group. The control group was treated with oral vitamin C and vitamin E while study group was treated with Erzhi Mingmu Decoction based on the same treatment of the control group. Both groups were continuously treated for 1 month, the visual improvement, fundus changes, and changes of serum VEGF and CRP levels were compared before and after treatment. RESULTS: The number of patients with visual improvement was higher in the study group than that in the control group(P < 0.05). The number of patients with fundus improvement in the study group was more than that of the control group(P < 0.05). Serum VEGF levels were decreased in the 2 groups after treatment, and they were decreased more in the study group than those in control group(all P < 0.05). Serum CRP levels were decreased in the 2 groups after treatment, and the serum CRP levels were decreased more in the study group than those in control group(all P < 0.05). CONCLUSION: The treatment of non-exudative age-related macular degeneration with Erzhimingmu Decoction can significantly improve the vision of patients, improve the condition of the fundus, and reduce the levels of serum VEGF and CRP, which is worthy of clinical promotion and application.

Comparison of visual acuity outcomes between ranibizumab and bevacizumab treatment in neovascular age-related macular degeneration

AIM: To compare visual acuity (VA) outcomes between intravitreal injection of bevacizumab and ranibizumab in the treatment of neovascular age-related macular degeneration (AMD). METHODS: We conducted a consecutive, retrospective case series study in patients with newly diagnosed all type choroidal neovascularization (CNV) secondary to AMD who received an intravitreal injection of bevacizumab (1.25mg) or ranibizumab (0.3mg) at Lions Eye Institute, Western Australia from Mar. 2006 to May 2008. All patients received injection at baseline with additional monthly injections given at the discretion of the treating physician. Main outcome measures were changes in VA. RESULTS: There were 371 consecutive patients received injection at least in one eye with at least 6 months of follow up (median of 12.0 months). Bevacizumab treatment prevented 221 out of 278 (79.5%) patient from losing < 15 letters in VA compared with 79 out of 93 (84.9%) of ranibizumab treated patients (P=0.25). While 68 (24.5%) of bevacizumab treated patients gained 15 letters of VA compared with 24 (25.8%) of ranibizumab treated patients (P=0.79). 75.3% and 66.2% patients benefited from ranibizumab and bevacizumab respectively with final VA better than 6/60 (P=0.10). Multivariate analysis showed that pre-treatment VA was negatively associated with benefit outcome. Assignment of injection was not associated with VA outcome of benefit after adjusting the covariate (P=0.857). CONCLUSION: There are no difference in treatment efficacy in terms of VA between bevacizumab and ranibizumab in routine clinical condition.

Bevacizumab vs ranibizumab for neovascular age-related macular degeneration in Chinese patients

AIM: To compare the clinical efficacy of intravitreal injections of bevacizumab and ranibizumab for treating Chinese patients with neovascular age-related macular degeneration (AMD).METHODS: Among 60 Chinese patients with exudative AMD (60 eyes), 28 received intravitreal bevacizumab injections (1.25mg) and 32 received intravitreal ranibizumab injections (0.5mg), once a month for 3 months and were followed for a total of 6 months. Monthly optical coherence tomography (OCT) was used to determine whether the patients received additional treatments during the follow-up. We compared the baseline and 6 -month follow-up values of mean best-corrected visual acuity (BCVA) and central retinal thickness (CRT) in both groups of patients. We also compared the occurrence of adverse events.RESULTS: At the 6-month follow-up, the mean BCVA (logMAR) of the bevacizumab and ranibizumab treatment groups improved from the baseline measurements of 0.72 ±0.23 and 0.73 ±0.22 to 0.47 ±0.14 and 0.45 ±0.20, respectively (P 【0.05 for both groups). However, the change was not significantly different between the two groups. As evaluated by OCT, CRT decreased from 366.71 ±34.72μm and 352 ±36.9μm at baseline to 250.86 ± 41.51μm and 243.22 ±41.38μm in the bevacizumab and ranibizumab groups, respectively (P 【0.05 for both groups). However, the change was not significantly different between the two groups. There were no severe local adverse reactions or systemic adverse events.CONCLUSION:Intravitreal bevacizumab and ranibizumab have equivalent effects on BCVA and CRT and appeare safe over the short-term.

Diabetic retinopathy and age-related macular degeneration: a survey of pharmacoutilization and cost in Calabria, Italy

The aged population is constantly growing, thus fostering an increase in age-dependent diseases. Among these, diabetic retinopathy (DR) along with age-related macular degeneration entails progressive vision loss. Since such conditions are associated with the proliferation of novel vessels, their pharmacotherapeutic management consists of the intravitreal injection of anti-vascular endothelial growth factor drugs, able to hinder the driving of vascular proliferation prompted by vascular endothelial growth factor. The humanized anti-vascular endothelial growth factor monoclonal antibody ranibizumab provided evidence for efficacy in several trials, hence earning approval by the US Food and Drug Administration for therapeutic use in all the stages of DR. Due to the lack of epidemiologic and pharmacoeconomic evaluation in the local Calabria Region context, the present retrospective observational study focused on prevalence of DR and age-related macular degeneration, treatment and cost of therapy with ranibizumab in 870 patients arriving to clinical observation at the "Mater Domini” University Hospital in Calabria, Italy from January 2014 to June 2017. Data were extracted from the database of ophthalmology ward and subjected to statistical analysis. The results suggest that the most frequent retinal diseases are age-related macular degeneration and DR and that the use of ranibizumab has been decreasing over the 4-year study period together with the associated cost per patient which was similar for both disorders. Therefore, appropriateness of treatment with drugs other than ranibizumab needs to be assessed in this setting and deep monitoring of pharmacologic treatment for retinal diseases is necessary to prevent or delay visual acuity decrease and complete vision loss. Study procedures were performed in accordance with the "Mater Domini” University Hospital ethical standards of the responsible committee on human experimentation.

Increased serum levels of soluble CD146 and vascular endothelial growth factor receptor 2 in patients with exudative age-related macular degeneration

AIM: To investigate serum levels of soluble CD146(s CD146) and vascular endothelial growth factor receptor 2(VEGFR2) in patients with age-related macular degeneration(AMD). METHODS: Eighty-eight patients with exudative AMD and 45 sex-and age-matched healthy controls were enrolled in this study conducted in China. Serum samples was obtained from the patients with exudative AMD and from the controls. Serum sCD146 and VEGFR2 protein levels were measured using an enzyme-linked immunosorbent assay.RESULTS: We found that serum sCD146 and VEGFR2 protein levels were significantly higher in the patients with exudative AMD group than in the controls(t=3.859, P<0.001 and t=3.829, P<0.001, respectively). Serum sCD146 levels were significantly higher in patients with classic choroidal neovascularization(CNV) than in those with occult CNV(t=9.899, P<0.001). There was a significant difference in the trend for exudative AMD in the highest versus lowest quartile of circulating sCD146 levels(χ2=10.29, P=0.001). The receiver operating characteristic curve analysis showed that the area under the curve was 0.696 for s CD146(95%CI: 0.601-0.791) with an optimum diagnostic cut-off value of 157.16 ng/mL, a sensitivity of 55.7%, and a specificity of 82.2%.CONCLUSION: The serum sCD146 level increases and may be a biomarker for exudative AMD.

Progress of clinical therapies for dry age-related macular degeneration

Dry age-related macular degeneration(AMD)is a progressive blinding disease that currently affects millions of people worldwide with no successful treatment available.Significant research efforts are currently underway to develop therapies aimed at slowing the progression of this disease or,more notably,reversing it.Here the therapies which have reached clinical trial for treatment of dry AMD were reviewed.A thorough search of Pub Med,Embase,and Clinicaltrials.gov has led to a comprehensive collection of the most recent strategies being evaluated.This review also endeavors to assess the status and future directions of therapeutics for this debilitating condition.

Combination of ranibizumab with photodynamic therapy vs ranibizumab monotherapy in the treatment of age-related macular degeneration: a systematic review and meta-analysis of randomized controlled trials

AIM:To compare the efficacy and safety of combination of ranibizumab with photodynamic therapy(PDT)vs ranibizumab monotherapy in the treatment of age-related macular degeneration(AMD).METHODS:The Cochrane Central Register of Controlled Trials(CENTRAL)in the Cochrane Library,Pubmed,and Embase were searched.There were no language or data restrictions in the search for trials.Only randomized controlled trials(RCTs)were included.Methodological quality of the literatures was evaluated according to the Jadad Score.RevMan 5.2.6 software was used to do the meta-analysis.RESULTS:Seven studies were included in our systematic review,among which four of them were included in quantitative analysis.The result shows that the ranibizumab monotherapy group had a better mean best corrected visual acuity(BCVA)change vs baseline at month 12 compared with that of the combination treatment group,and the statistical difference was significant(WMD,-2.61;95%CI,-5.08 to-0.13;P=0.04).However,after the removal of one study,the difference between the two groups showed no significant difference(WMD,-2.29;95%CI,-4.81 to 0.23;P=0.07).Meanwhile,no significant central retinal thickness(CRT)reduction was found in the combination treatment group and the ranibizumab monotherapy group at 12 months follow-up.Nevertheless,the combination group tended to have a greater reduction in CRT(WMD,-4.13μm;95%CI,-25.88to 17.63,P=0.71).The proportion of patients gaining more than 3 lines at month 12 in the ranibizumab group was higher than in the combination group and there was a significant difference(RR,0.72;95%CI,0.54 to 0.95;P=0.02).Whereas there was no significant difference for the proportion of patients gaining more than 0 line at month12 between the two groups(RR,0.93;95%CI,0.76 to1.15;P=0.52).The general tendency shows a reduction in ranibizumab retreatment number in the combination treatment group compared with the ranibizumab monotherapy group.As major adverse events,the differences in the number of eye pain,endophthalmitis,hypertension and arterial thromboembolic events were not significant between the two groups,and the incidence of serious adverse events in the two groups was very low.CONCLUSION:For the maintenance of vision,the comparison of the combination of ranibizumab with PDT vs ranibizumab monotherapy shows no apparent difference.Compared with the combination of ranibizumab and PDT,patients treated with ranibizumab monothearpy may gain more visual acuity(VA)improvement.The combination treatment group had a tendency to reduce the number of ranibizumab retreatment.Both the two treatment strategies were well tolerated.