Comparison of the cytokines levels in aqueous humor in vitrectomized eyes versus non-vitrectomized eyes with diabetic macular edema.

BACKGROUND: This study was conducted to compare concentrations of VEGF family growth factors, inflammation-related factors, and adhesion molecules in the aqueous humor of eyes with diabetic macular edema (DME), with and without prior vitrectomy. METHODS: A total of 31 eyes were included, 11 with DME that had undergone vitrectomy, 9 with DME but without vitrectomy, and 11 from age-related cataract patients as controls. The concentrations of cytokines including TNF-α, IL-6, IL-8, IP-10, MCP-1, IFN-γ, MIP-1 α, MIP-1 ß, PECAM-1, MIF, VCAM-1, ICAM-1, PIGF were quantified using Luminex Human Discovery Assay. Central macular thickness (CMT) values of all eyes were measured using optical coherence tomography (OCT). RESULTS: (1) Vitrectomized DME eyes exhibited significantly higher levels of IL-6 and IL-8 compared to non-vitrectomized eyes (P < 0.05). (2) In vitrectomized group, after Benjamini-Hochberg correction, there was a significant positive correlation between the levels of VEGF and PlGF (rs = 0.855, P < 0.05), as well as the levels of TNF-α and IFN-γ (rs = 0.858, P < 0.05). In non-vitrectomized group, significant positive correlations were found between VEGF and PlGF levels after correcting for multiple comparisons (rs = 0.9, P < 0.05). (3) In non-vitrectomized group, the concentrations of VEGF and PlGF in aqueous humor were significantly positively correlated with CMT values (rs = 0.95, P < 0.05; rs = 0.9, P < 0.05, respectively). CONCLUSIONS: The concentrations of IL-6 and IL-8 in the aqueous humor were significantly higher in vitrectomized DME eyes compared to nonvitrectomized DME eyes and the levels of VEGF were similar in the two groups, suggesting that inflammation after vitrectomy may be a key factor in the occurrence and development of DME.

High Vasohibin-2 expression correlated with autophagy in proliferative diabetic retinopathy.

Vasohibin-2 (VASH2) is confirmed to be associated with angiogenesis. To investigate the vitreous levels of VASH2 and how VASH2 induces angiogenesis in proliferative diabetic retinopathy (PDR), a total of 120 eyes were enrolled in this prospective and randomized controlled study and the vitreous level of VASH2 was quantified by Luminex liquid suspension chip. Vector systems were applied in human retinal microvascular endothelial cells (HRMECs) for VASH2 gene overexpression, along with interfering lentiviral vectors (VASH2-shRNA) for VASH2 gene silencing. Cell migration, autophagic flux, as well as the expression of α-tubulin, detyrosinated ⍺-tubulin, LC3 II/LC3 I, P62 were detected under normal, VASH2 overexpression, or interference conditions. The level of VASH2 in PDR patients was significantly higher (218.61 ± 30.14 pg/ml) than that in ERM/MH patients (80.78 ± 2.05 pg/ml) (P = 0.001). The migration ability of HRMECs was significantly increased in VASH2 overexpression group, while in the interfering group, the migration ability decreased. VASH2 increased the detyrosination of ⍺-tubulin. The high fluorescence intensity of autophagic flux showed an activation of autophagy in VASH2 overexpression group, which was also confirmed by the increase of LC3 II/LC3 I ratio and the decrease of P62. Collectively, the present study shows in PDR, vitreous level of VASH2 is higher. VASH2 promotes neovascularization by inducing autophagy, suggesting VASH2 could be a new anti-angiogenic drug target for PDR.

Effect of Intravitreal Conbercept Injection on Complications of Pars Plana Vitrectomy in Patients with Proliferative Diabetic Retinopathy.

BACKGROUND: The effect of intravitreal conbercept (IVC) before pars plana vitrectomy (PPV) on surgical complications in patients with proliferative diabetic retinopathy (PDR) was observed. METHODS: A total of 152 patients with PDR operated on in Jiangsu Provincial People's Hospital from November 2019 to November 2020 were divided into two groups: 124 patients in the preoperative intravitreal conbercept injection + PPV group (IVC group) and 28 patients in the PPV only group (No-IVC group). Vitreous samples were collected in all eyes of patients who underwent vitrectomy, and the content of VEGF-A was measured by Luminex. The effect of conbercept on intraoperative and postoperative complications of PDR was assessed. RESULTS: The content of VEGF in the vitreous of the IVC group was significantly lower than that in the No-IVC group (64.50 ± 58.40 pg/mL vs. 805.17 ± 417.60 pg/mL, p < 0.001). During postoperative follow-up, early postoperative vitreous hemorrhage (VH) occurred in 13 of 142 eyes (9.15%). Compared with the No-IVC group, PDR patients with VH and fibrovascular membrane (FVM) or high complexity in the IVC group had lower intraoperative bleeding rates (p < 0.05). The early postoperative hemorrhage rate in the IVC group was lower than in the No-IVC group (6.03% vs. 23.08%, p < 0.05). The number of intraoperative electrocoagulation and iatrogenic retinal holes in the IVC group was significantly lower than in the No-IVC group (p < 0.05). There were no significant differences in intraocular hypertension and NVG numbers between the two groups. Visual acuity in both groups improved after PPV surgery, reaching the highest level in the 3rd month after the operation. CONCLUSIONS: IVC before PPV can reduce the level of VEGF-A in the vitreous body and reduce surgical complications.

The clinical and genetic findings in a Chinese family with Axenfeld-Rieger syndrome.

Objecive: To describe the clinical and genetic findings of an Axenfeld-Rieger syndrome (ARS) family with a new PITX2 splicing mutation. Methods: A Chinese ARS family with five affected individuals was recruited. Exome sequencing was performed on the proband and the variant (C.253-9C > A) in PITX2 gene was detected as a pathogenic mutation. Sanger sequencing was performed for verification and cosegregation analysis. Real-time polymerase chain reaction (RT- PCR) and Western blotting were performed to verify the expression of the pathogenic gene. Results: All the patients showed abnormalities in the anterior segment of both eyes including posterior embryotoxon, corectopia, iris dysplasia, and iridocorneal tissue adhesions. In addition, they all presented systemic features, including maxillary hypoplasia, underbite, hypodontia, conical teeth. Only III-7 showed obvious umbilical skin. In the PITX2 family, we identified a novel heterozygous splicing mutation (C.253-9C > A) which was confirmed by Sanger sequencing to be completely cosegregated with the ARS phenotype. Real-time quantitative PCR and Western results showed that PITX2 mRNA and protein expression were significantly lower in patients compared with unrelated normal controls. Conclusion: In the ARS pedigree, we summarized the variable phenotype, described a novel PITX2 splicing mutation which expand the genetic spectrum of ARS. We further confirmed the possibility of development of ARS induced by this PITX2 gene deficiency.

Ranibizumab plus fufang xueshuantong capsule versus ranibizumab alone for exudative age-related macular degeneration.

OBJECTIVE: To compare the efficacy of ranibizumab plus fufang xueshuantong capsule (cFXST) with the efficacy of ranibizumab alone in treatment of exudative age-related macular degeneration. METHODS: This prospective, randomized, controlled, pilot study included 38 eyes from 38 patients with exudative age-related macular degeneration (AMD) that were randomly allocated into two cohorts of 19 eyes each: ranibizumab (Cr) and ranibizumab plus cFXST (Cfr). All patients received three monthly injections of ranibizumab. Patients in Cfr also received daily oral supplementation of cFXST. Best corrected visual acuity (BCVA) and thickness of the choroidal neovascularization-pigment epithelial detachment (CNV-PED) complex (measured by optical coherence tomography) were recorded at baseline and at 1 and 3 months after the first intravitreal injection of ranibizumab. RESULTS: In the Cfr, the CNV-PED complex thickness was reduced by 31.7% and 36.1% at 1 and 3 months, respectively; these reductions were significantly greater than the 19.7% and 24.2% reductions in the Cr. BCVA improvement was significantly greater in the Cfr than in the Cr after 3 months; the proportion of patients with functional response was also greater in the Cfr than in the Cr (16/16 vs. 8/17). CONCLUSION: Oral cFXST increases the efficacy of short-term ranibizumab treatment for exudative AMD.

A review on vasohibin and ocular neovascularization.

Ischemic and neovascular disease is one of the most difficult ocular diseases to deal with nowadays. Redundancy, poor visual acuity and decreased life quality are bothering patients and ophthalmologists for decades. After vascular endothelial growth factor (VEGF) was found to be a primary factor in promoting retinal angiogenesis, intravitreal injection of anti-VEGF drugs has been the first-line treatment. Whereas, some patients are refractory to this therapy and problems of economic burden, local complications and adverse effects promote researches into other possible targets. The vasohibin (VASH) family is a newly-investigated factor in modulating ocular angiogenesis. The family includes VASH1 and VASH2, which show opposite effects of inhibiting and accelerating angiogenesis respectively. Positive results have been reported in cellular and animal experiments. With further researches, it can be a promising future target of treating ocular neovascular diseases.

Expression of Neovascular Associated Factors PEDF and αB-crystallin in Human Lens Epithelial Cells.

Objective: To investigate the expression of pigment epithelium-derived factor (PEDF) and αB-crystallin in human lens epithelial cells (LEC) and explore their relationships with diabetes. Methods: Lens anterior capsules attached with LEC were collected from cataract surgeries in patients with or without diabetes, and grouped as following: non-diabetes mellitus (NDM) group, no diabetic retinopathy (NDR) group, non-proliferative diabetic retinopathy (NPDR) group and proliferative diabetic retinopathy (PDR) group. The expression of PEDF and αB-crystallin in all groups was determined by Western blot and immunofluorescence assay. Results: PEDF and αB-crystallin protein were both detected in LEC. PEDF was mainly distributed in the cytoplasm, whereas αB-crystallin was present in both cytoplasm and nucleus. The levels of PEDF protein and αB-crystallin protein in LEC were significantly increased with the appearance and aggravation of diabetic retinopathy (DR) (p < .01). Conclusion: The expression of PEDF and αB-crystallin protein is both positively correlated with the progression of DR, which may contribute to the regulation of iris neovascularization.

A modified method for suprachoroidal fluid drainage in kissing choroidal detachment.

AIM: To introduce a new method for suprachoroidal fluid drainage before 23-gauge pars plana vitrectomy. METHODS: A 15° side-port blade was firstly used to create a sclerotomy into the suprachoroidal space for initial drainage. A 30-guage needle was then applied to inject balanced saline solution through the existing sclerotomy for further drainage. After most of the suprachoroidal fluid was drained, standard 3-port 23-guage pars plana vitrectomy was performed. RESULTS: We have succeeded in using this technique to treat five patients with retinal detachment and kissing choroidal detachment (KCD). The choroidal detachment was visibly recessed in all cases after drainage with no intraoperative complications. After removal of silicon oil at 3mo follow-up, all patients obtained a reattached retina. No postoperative complications such as hypotony and endophthalmitis occurred. CONCLUSION: The new technique is efficient and safe for suprachoroidal fluid drainage for patients with rhegmatogenous retinal detachment. In future, further larger series are needed to attest to its safety and efficacy.

Efficacy and safety of vitrectomy with internal limiting membrane peeling for diabetic macular edema: a Meta-analysis.

AIM: To evaluate the efficacy and safety of vitrectomy with internal limiting membrane (ILM) peeling for diabetic macular edema (DME). METHODS: The PubMed, Embase, Web of Science, Cochrane, SionMed, ClinicalTrials.gov, CNKI databases and Wanfang databases, published until Oct. 2017, were searched to identify studies comparing the clinical outcomes following vitrectomy with and without ILM peeling, for treating DME. Pooled results were expressed as odds ratios (ORs) with corresponding 95% confidence intervals (CI) for vitrectomy with and without ILM peeling with regard to best corrected visual acuity (BCVA), central macular thickness (CMT), and complication incidents. RESULTS: A total of 14 studies involving 857 eyes were included of which three studies were Chinese and the rests were English literatures. Meta-analysis indicated that compared with vitrectomy alone, vitrectomy with ILM peeling could improve BCVA more obviously (OR=1.66, 95%CI: 1.12-2.46, P=0.01) and had higher rate of CMT reduction (OR=3.89, 95%CI: 1.37-11.11, P=0.01). There were significant statistical differences between the two surgical methods for both BCVA and CMT (P<0.05). For the incidence of intraoperative and postoperative complications, the incidence of epiretinal membrane (ERM) was slightly lower in the ILM peeling group than the group without ILM peeling (OR=0.38, 95%CI: 0.07-2.00, P=0.25), although insignificant statistically. Other incidences of overall complications, iatrogenic peripheral retinal break and increased intraocular pressure indicated no significant difference between two groups (OR=1.19, 95%CI: 0.82-1.73, P=0.36; OR=1.21, 95%CI: 0.66-2.21, P=0.53; OR=1.34, 95%CI: 0.75-2.40, P=0.32). CONCLUSION: Vitrectomy is effective for DME and the effect can be improved by additional ILM peeling, especially for anatomical efficacy, without increasing the incidence of intraoperative and postoperative complications. However, it is imperative to gain more evaluation in the future due to the paucity of prospective randomized study.

Thin Rigid Contact Lens Used in Vitreous-Retinal Surgery for Corneal Protection: A Randomized Controlled Trial.

PURPOSE: To design a rigid contact lens (CL) to be used in combination with a wide-angle viewing system and analyze its protection for corneal epithelial during vitreous-retinal surgery. METHODS: A thin and lightweight rigid CL was designed and constructed. The impact of the CL on the visualized fundus range was evaluated using a concrete eye model. Patients with severe proliferative diabetic retinopathy (PDR) were randomized to either the CL group, corneal protective agent (CPA) group, or balanced salt solution (BSS) group. All patients underwent phacoemulsification and a standard 23-gauge three-port vitrectomy. Surgery time and corneal fluorescein staining score (FSS) postoperatively were mainly measured. RESULTS: In the eye model, a larger area of fundus was visualized with the use of our CL under 128 D or 60 D Resight lens. The mean surgery time was 51.36±8.06 min, 50.89±8.26 min, and 55.46±9.14 in CL, CPA, and BSS group, respectively (F=2.325, P=0.105). In eight eyes in the BSS group, corneal epithelial layer was peeled off because the dryness of the cornea could not maintain a clear fundus image. The FSS in BSS group was markedly higher than that of CL and BSS group 1 day (P<0.001), 3 days (P<0.001), and 7 days (P=0.002) postoperatively. There was no statistical significance of the FSS between CL and CPA group at each follow-up endpoint. CONCLUSIONS: The CL that we designed can slightly enlarge the visible fundus range and efficiently protect corneal epithelium during vitrectomy for patients with PDR.

Ocular pulse amplitude in different types of glaucoma using dynamic contour tonometry: Diagnosis and follow-up of glaucoma.

The aim of the present study was to compare the ocular pulse amplitude (OPA) in patients with different types of glaucoma using dynamic contour tonometry (DCT), to evaluate ocular and systemic factors associated with the OPA and to verify whether OPA measured by DCT is an independent predictor for glaucoma diagnosis. A total of 217 eyes of 217 participants in the following five groups were included in this cross-sectional study: Chronic angle closure glaucoma (CACG), primary open angle glaucoma, normal tension glaucoma (NTG), suspected open angle glaucoma (SOAG) and normal control (NC). The following tests were simultaneously performed during a single visit: Intra-ocular pressure (IOP), OPA, cup-to-disk (C/D) ratio, mean damage (MD) and loss variance (LV). OPAs were compared in each group. The association between OPA and IOP, age, C/D ratio, MD and LV was detected. OPA analysis prior to and after trabeculectomy was also performed to assess its prognostic value. Among the 217 individuals, the OPA was consistent with the IOP, both measured by DCT, along with the MD and LV. Patients with CACG and SOAG had higher OPA values than those with NTG and normal controls. Compared with patients aged >30 years, the OPA was significantly lower in younger patients, while they may not have been affected by different C/D ratios. After trabeculectomy, the OPA had significantly decreased compared with the values prior to surgery. In conclusion, the present study showed that the OPA is correlated with the IOP determined by DCT. CACG and SOAG patients had higher OPA values than patients with other types of glaucoma. OPA measured by DCT may be a predictor for glaucoma diagnosis and prognosis.

Protective effect of miR-200b/c by inhibiting vasohibin-2 in human retinal microvascular endothelial cells.

AIMS: Proliferative diabetic retinopathy (PDR), characterized by angiogenesis, can cause serve vision loss and even blindness. Recent studies have suggested a pivotal role of vasohibin-2 (VASH2) in the promotion of angiogenesis in tumor tissues. Here we further investigated the role of VASH2 in the proliferation and migration of retinal endothelial cells. MAIN METHODS: The expression of VASH2 in vascular endothelial cells of epiretinal fibrovascular membranes (FVMs) from PDR patients were detected by immunofluorescence. VASH2 gene interfering lentiviral vectors (VASH2-shRNA) and miR-200b/c were constructed for the evaluation of the VASH2 effect on high glucose induced human retinal microvascular endothelial cell line (HRMECs). Cell proliferation, cell cycle and cell migration were carried out subsequently. The relationship between VASH2 and miR-200b/c was determined by luciferase reporter gene assays. KEY FINDINGS: A positive expression of VASH2 was identified in vascular endothelial cells of FVMs from PDR patients. In HRMECs, cells transfected with shRNA or miR-200b/c mimics showed a significantly reduced VASH2 expression compared with negative control group by real time-polymerase chain reaction and western-blot analysis. Inhibition of VASH2 was demonstrated to suppress cell proliferation and migration from Day 2 to Day 4. The luciferase reporter gene assays confirmed the post-transcriptional regulation of VASH2 by miR-200b/c in HRMECs. SIGNIFICANCE: The present study suggests a protective effect of miR-200b/c on high glucose induced HRMECs dysfunction by inhibiting VASH2. It could be a potential therapeutic strategy to inhibit angiogenesis for the treatment of retinal vascular disease.

Protection of Mcc950 against high-glucose-induced human retinal endothelial cell dysfunction.

Diabetic retinopathy (DR) is a well-known microvascular complication related to inflammation. Mcc950 is a potent and specific inhibitor of the NLRP3 inflammasome but its influence on DR has not been studied. Thus, we evaluated the anti-inflammatory effects of Mcc950 on high-glucose-induced human retinal endothelial cells (HRECs) and the potential underlying mechanism. In surgical excised proliferative membranes from DR patients, high expression of NLRP3, caspase 1 and IL-1ß was observed and co-localization of NLRP3 and IL-1ß occurred in CD31+ labeled HRECs. Moreover, in high-glucose-stimulated HRECs, increased production of the NLRP3 inflammasome activation and severe apoptosis were rescued with Mcc950 treatment. Additionally, the inhibitory effect of Mcc950 was mimicked through downregulation of NEK7 by siRNA in high-glucose-induced HRECs and Mcc950 treatment remarkably inhibited Nek7 and NLRP3 interactions by co-immunoprecipitation, suggesting that Mcc950 may be a potentially protective agent against inflammation, likely via downregulation of the Nek7-NLRP3 pathway. In conclusion, Mcc950 inhibited HREC dysfunction under high-glucose conditions and this research may offer insight for future pharmaceutical approaches for treating DR.

Knockout of Ccr2 alleviates photoreceptor cell death in rodent retina exposed to chronic blue light.

Age-related macular degeneration (AMD), the leading cause of visual loss after the age of 60 years, is a degenerative retinal disease involving a variety of environmental and hereditary factors. Although it has been implicated that immune system is involved in the disease progression, the exact role that microglia has is still unclear. Here we demonstrated that knockout of Ccr2 gene could alleviate photoreceptor cell death in mice retinas exposed to chronic blue light. In Ccr2-/- mice, a damaged microglia recruitment was shown in retina and this could protect the visual function in electroretinogram and alleviate the photoreceptor apoptosis, which thus helped attenuate the blue light-induced retinopathy. We further found an increased co-location of NLRP3, Iba-1, and IL-1ß in fluorescence and a concomitant increased protein expression of NLRP3, caspase-1, and IL-1ß in western blotting in chronic blue light-induced retinopathy. Moreover, the activation of microglia and their cellular NLRP3 inflammasomes occurred as an earlier step before the structural and functional damage of the mice retinas, which collectively supported that microglial NLRP3 inflammasome might be the key to the chronic blue light-induced retinopathy.

Face-down or no face-down posturing following macular hole surgery: a meta-analysis.

PURPOSE: To evaluate the impact of postoperative posturing with or without face-down on the anatomical and functional outcomes of macular hole surgery. METHODS: A literature-based meta-analysis was conducted to identify studies relevant to posturing following macular hole surgery (MHS). PubMed and Web of Science databases were used to retrieve articles up to 1 June 2015. The primary measures included MH closure and ideal vision acuity improvement. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were estimated in Review Manager. RESULTS: Four randomized control trials (RCTs) comprising 251 cases were included in the final meta-analysis. No face-down posturing (FDP) after MHS revealed lower anatomic success rate compared to face-down posturing (OR = 0.33, 95% CI [0.13, 0.81], p = 0.02). For holes smaller than 400 µm in size, the subgroup meta-analysis indicated no significant effect of FDP on successful hole closure (OR = 0.29, 95% CI [0.01, 7.34], p = 0.45). However, when holes were larger than 400 µm, it seemed less effective on MH closure following surgery in no FDP group (OR = 0.23, 95% CI [0.07, 0.71]), and this was statistically significant (p = 0.01). CONCLUSIONS: Our work found that no FDP was not inferior to its face-down counterpart for the success of MHS when macular holes were smaller than 400 µm in size. For macular holes larger than 400 µm, statistical analysis proved that FDP might be necessary. More well-conducted randomized control trials are needed to verify our findings.

Association between transcription factor 7-like 2 rs7903146 polymorphism and diabetic retinopathy in type 2 diabetes mellitus: A meta-analysis.

As one of the vascular complications of type 2 diabetes mellitus, the incidence of diabetes retinopathy is greatly increasing worldwide. Both genetic and environmental factors are involved in the pathologies. A meta-analysis was conducted to assess the association between transcription factor 7-like 2 polymorphism (rs7903146) and type 2 diabetic retinopathy. Published literature from PubMed, Web of Science and China National Knowledge Infrastructure were retrieved. Pooled odds ratios with 95% confidence intervals were calculated to estimate the strength of the association. Eight studies including 6422 participants were included in the final meta-analysis. Our analysis provides substantial evidence that the rs7903146 variant is significantly associated with the risk of diabetic retinopathy in Caucasian populations while not in East Asian populations. The variant of rs7903146 appeared more likely to be a promising genetic biomarker of diabetic retinopathy in Caucasians.

Association between variants A69S in ARMS2 gene and response to treatment of exudative AMD: a meta-analysis.

A study was undertaken to investigate the association between A69S in age-related maculopathy susceptibility 2 (ARMS2) and the response to anti-angiogenesis treatment in exudative age-related macular degeneration (AMD). A literature-based meta-analysis was performed of studies relevant to A69S and the response to anti-angiogenesis treatment. PubMed, Web of Science, China National Knowledge Infrastructure (CNKI) and Sinomed databases were used to retrieve articles up to July 2014. Pooled ORs and 95% CIs were estimated using fixed and random effects models in Stata V.9.0. Q-statistic testing was used to assess heterogeneity. Twelve articles comprising 2389 cases were included in the final meta-analysis. The analysis of the overall population indicated a statistically significant association between A69S and the response to anti-angiogenesis treatment in exudative AMD (GG vs TT: OR 1.34 (95% CI 1.01 to 1.77), p=0.039; GT vs TT: OR 1.58 (95% CI 1.08 to 2.31), p=0.018; GG+GT vs TT: OR 1.74 (95% CI 1.19 to 2.52), p=0.004). In subgroup analysis, A69S appeared more likely to be a predictor for anti-angiogenic response in the East Asian population (GG vs TT: OR 1.65 (95% CI 1.02 to 2.68), p=0.042; GT vs TT: OR 1.66 (95% CI 1.17 to 2.37), p=0.005; GG+GT vs TT: OR 1.82 (95% CI 1.07 to 3.10), p=0.027; G vs T: OR 1.56 (95% CI 1.01 to 2.41)). However, no statistical significance was found in the Caucasian subgroup analysis. This study shows an association between A69S polymorphism in the ARMS2 gene and the anti-angiogenesis treatment response. A69S could be considered predictive of the anti-angiogenic effects, especially in Asian populations.

Protective effects of astragaloside IV on db/db mice with diabetic retinopathy.

OBJECTIVES: Diabetic retinopathy (DR) is a common diabetic eye disease which is well-known as the result of microvascular retinal changes. Although the potential biological functions of astragaloside IV (AS IV) have long been described in traditional system of medicine, its protective effect on DR remains unclear. This study aims to investigate the function and mechanism of AS IV on type 2 diabetic db/db mice. METHODS: Db/db mice were treated with AS IV (4.5 mg/kg or 9 mg/kg) or physiological saline by oral gavage for 20 weeks along with db/m mice. In each group, retinal ganglion cell (RGC) function was measured by pattern electroretinogram (ERG) and apoptosis was determined by Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. Blood and retina aldose reductase (AR) activity were quantified by chemiluminescence analysis. The expressions of phosporylated-ERK1/2, NF-κB were determined by Western blot analysis. Furthermore, the expression of related downstream proteins were quantified by Label-based Mouse Antibody Array. RESULTS: Administration of AS IV significantly improved the amplitude in pattern ERG and reduced the apoptosis of RGCs.in db/db mice. Furthermore, downregulation of AR activity, ERK1/2 phosphorylation, NF-κB and related cytokine were observed in AS IV treatment group. CONCLUSIONS: Our study indicated that AS IV, as an inhibitor of AR, could prevent the activation of ERK1/2 phosporylation and NF-kB and further relieve the RGCs disfunction in db/db mice with DR. It has provided a basis for investigating the clinical efficacy of AR inhibitors in preventing DR.

Serum miRNA biomarkers serve as a fingerprint for proliferative diabetic retinopathy.

BACKGROUND: Diabetic retinopathy (DR) is a retinopathy resulting from diabetes mellitus (DM) which was classified into non-proliferative DR (NPDR) and proliferative DR (PDR). Without an early screening and effective diagnosis, patients with PDR will develop serious complications. Therefore, we sought to identify special serum microRNAs (miRNAs) that can serve as a novel non-invasive screening signature of PDR and test its specificity and sensitivity in the early diagnosis of PDR. METHODS: In total, we obtained serum samples from 90 PDR cases, 90 matched NPDR patients and 20 controls. An initial screening of miRNA expression was performed through TaqMan Low Density Array (TLDA). The candidate miRNAs were validated by individual reverse transcription quantitative real-time PCR (RT-qPCR) arranged in an initial and a two-stage validation sets. Moreover, additional double-blind testing was performed in 20 patients clinically suspected of having DR to evaluate the diagnostic value and accuracy of the serum miRNA profiling system in predicting PDR. RESULTS: Three miRNAs were significantly increased in patients with PDR compared with NPDR after the multiple stages. The areas under the receiver operating characteristic (ROC) curves of the validated three-serum miRNAs signature were 0.830, 0.803 and 0.873 in the initial and two validation sets, respectively. Combination of miR-21, miR-181c, and miR-1179 possessed a moderate ability to discrimination between PDR and NPDR with an area under ROC value of 0.89. The accuracy rate of the three-miRNA profile as PDR signature was 82.6%. CONCLUSIONS: These data provide evidence that serum miRNAs have the potential to be sensitive, cost-effective biomarkers for the early detection of PDR. These biomarkers could serve as a dynamic monitoring factor for detecting the progression of PDR from NPDR.