Smurf1: A possible therapeutic target in dry age-related macular degeneration.

Smad ubiquitylation regulatory factor-1 (Smurf1) is one of C2-WW-HECT domain E3 ubiquitin ligases, it can regulate BMP pathway by mediating ubiquitylation degradation of Smad1/Smad5. Many functions about Smurf1 also are still unknown, especially in retina. This research is about to explore the role of Smurf1 in retina degeneration. Tail vein injection of sodium iodate (NaIO3) in C57BL/6J mice was the animal model of retina degeneration. In NaIO3 model, Smurf1 had more expression than normal mice. Specific Smurf1 inhibitor, A01, was injected into vitreous cavity. Results showed that inhibiting Smurf1 could alleviate acute retina injury, such as keeping a better retina structure in living imaging and histologic sections, less cell death and inflammation activation. Tert-butyl hydroperoxide (TBH) was used to establish oxidative stress injury in human retinal pigments epithelial cell line (ARPE-19). Oxidative stress injury gradually caused co-upregulation of Smurf1, TGF-ß1 and phosphorylated NF-κB (pNF-κB). TGF-ß1 could directly induce Smurf1 expression. Inhibiting Smurf1 had an anti-epithelial mesenchymal transition (anti-EMT) function. Similarly, A01 also could inhibit the expression of pNF-κB, NLRP3 and IL-1ß. At last, after searching bioinformatics database, Smurf1 had a possible interaction with beta-transducin repeat containing E3 ubiquitin protein ligase (ß-TrCP), another E3 ubiquitin ligases. ß-TrCP can mediate ubiquitination degradation of p-IκBα. Lentivirus-SMURF1 was used to overexpress Smurf1, and GS143 was used to inhibit ß-TrCP. The results showed Smurf1 could directly induce NF-κB, pNF-κB, and NLRP3 expression, and keep a stable ß-TrCP expression. However, inhibiting ß-TrCP could cause more NF-κB activation and NLRP3 expression. Therefore, ß-TrCP may play a negative role in NF-κB pathway activation. In summary, Smurf1 plays a role in exacerbating oxidative stress injury and inflammation in retina and may become a potential therapeutic target in ROS injury of retina.

Inhibition of Drp1 ameliorates diabetic retinopathy by regulating mitochondrial homeostasis.

Diabetic retinopathy (DR) is a potentially blinding complication resulting from diabetes mellitus (DM). Retinal vascular endothelial cells (RMECs) dysfunction occupies an important position in the pathogenesis of DR, and mitochondrial disorders play a vital role in RMECs dysfunction. However, the detailed mechanisms underlying DR-induced mitochondrial disorders in RMECs remain elusive. In the present study, we used High glucose (HG)-induced RMECs in vitro and streptozotocin (STZ)-induced Sprague-Dawley rats in vivo to explore the related mechanisms. We found that HG-induced mitochondrial dysfunction via mitochondrial Dynamin-related protein 1(Drp1)-mediated mitochondrial fission. Drp1 inhibitor, Mdivi-1, rescued HG-induced mitochondrial dysfunction. Protein Kinase Cδ (PKCδ) could induce phosphorylation of Drp1, and we found that HG induced phosphorylation of PKCδ. PKCδ inhibitor (Go 6983) or PKCδ siRNA reversed HG-induced phosphorylation of Drp1 and further mitochondrial dysfunction. The above studies indicated that HG increases mitochondrial fission via promoting PKCδ/Drp1 signaling. Drp1 induces excessive mitochondrial fission and produces damaged mitochondrial, and mitophagy plays a key role in clearing damaged mitochondrial. Our study showed that HG suppressed mitophagy via inhibiting LC3B-II formation and p62 degradation. 3-MA (autophagy inhibitor) aggravated HG-induced RMECs damage, while rapamycin (autophagy agonist) rescued the above phenomenon. Further studies were identified that HG inhibited mitophagy by down-regulation of the PINK1/Parkin signaling pathway, and PINK1 siRNA aggravated HG-induced RMECs damage. Further in-depth study, we propose that Drp1 promotion of Hexokinase II (HK-II) separation from mitochondria, thus inhibiting HK-II-PINK1-mediated mitophagy. In vivo, we found that intraretinal microvascular abnormalities (IRMA), including retinal vascular leakage, acellular capillaries, and apoptosis were increased in STZ-induced DR rats, which were reversed by pretreatment with Mdivi-1 or Rapamycin. Altogether, our findings provide new insight into the mechanisms underlying the regulation of mitochondrial homeostasis and provide a potential treatment strategy for Diabetic retinopathy.

PGE2 promotes macrophage recruitment and neovascularization in murine wet-type AMD models.

Age-related macular degeneration (AMD), a progressive chronic disease of the central retina, is a leading cause of blindness worldwide. Activated macrophages recruited to the injured eyes greatly contribute to the pathogenesis of choroidal neovascularization (CNV) in exudative AMD (wet AMD). This study describes the effects of cyclooxygenase-2 (COX2)/prostaglandin E2 (PGE2) signalling on the macrophage activation and CNV formation of wet AMD. In a mouse model of laser-induced wet AMD, the mice received an intravitreal injection of celecoxib (a selective COX2 inhibitor). Optical coherence tomography (OCT), fundus fluorescein angiography (FFA), choroidal histology of the CNV lesions, and biochemical markers were assessed. The level of PGE2 expression was high in the laser-induced CNV lesions. Macrophage recruitment and CNV development were significantly less after celecoxib treatment. E-prostanoid1 receptor (EP1R)/protein kinase C (PKC) signalling was involved in M2 macrophage activation and interleukin-10 (IL-10) production of bone marrow-derived macrophages (BMDMs) in vitro. In addition, IL-10 was found to induce the proliferation and migration of human choroidal microvascular endothelial cells (HCECs). Thus, the PGE2/EP1R signalling network serves as a potential therapeutic target for CNV of the wet-type AMD. Video abstract.

Protective roles of the TIR/BB-loop mimetic AS-1 in alkali-induced corneal neovascularization by inhibiting ERK phosphorylation.

Hydrocinnamoyl-L-valylpyrrolidine (AS-1), a synthetic low-molecule mimetic of myeloid differentiation primary response gene 88 (MyD88), inhibits inflammation by disrupting the interaction between the interleukin-1 receptor (IL-1R) and MyD88. Here, we describe the effects of AS-1 on injury-induced increases in inflammation and neovascularization in mouse corneas. Mice were administered a subconjunctival injection of 8 µL AS-1 diluent before or after corneal alkali burn, followed by evaluation of corneal resurfacing and corneal neovascularization (CNV) by slit-lamp biomicroscopy and clinical assessment. Corneal inflammation was assessed by whole-mount CD45+ immunofluorescence staining, and corneal hemangiogenesis and lymphangiogenesis following injury were evaluated by immunostaining for the vascular markers isolectin B4 (IB4) and the lymphatic vascularized marker lymphatic vessel endothelial hyaluronan receptor 1 (LYVE1), respectively. Additionally, corneal tissues were collected to determine the expression of 35 cytokines, and we detected activation of IL-1RI, MyD88, and mitogen-activated protein kinase (MAPK). The results showed that alkali conditions increased the number of CD45+ cells and expression of vascular endothelial growth factor (VEGF)-A, VEGF-C, and LYVE1 in corneas, with these levels decreased in the AS-1-treated group. Moreover, AS-1 effectively prevented alkali-induced cytokine production, blocked interactions between IL-1RI and MyD88, and inhibited MAPK activation post-alkali burn. These results indicated that AS-1 prevented alkali-induced corneal hemangiogenesis and lymphangiogenesis by blocking IL-1RI-MyD88 interaction, as well as extracellular signal-regulated kinase phosphorylation, and could be efficacious for the prevention and treatment of corneal alkali burn.

Prostaglandin E2 promotes pathological retinal neovascularisation via EP4R-EGFR-Gab1-AKT signaling pathway.

Proliferative retinopathies, such as proliferative diabetic retinopathy (PDR) and retinopathy of prematurity (ROP) are major causes of visual impairment and blindness in industrialized countries. Prostaglandin E2 (PGE2) is implicated in cellular proliferation and migration via E-prostanoid receptor (EP4R). The aim of this study was to investigate the role of PGE2/EP4R signaling in the promotion of retinal neovascularisation. In a streptozotocin (STZ)-induced diabetic model and an oxygen-induced retinopathy (OIR) model, rats received an intravitreal injection of PGE2, cay10598 (an EP4R agonist) or AH23848 (an EP4R antagonist). Optical coherence tomography, retinal histology and biochemical markers were assessed. Treatment with PGE2 or cay10598 accelerated pathological retinal angiogenesis in STZ and OIR-induced rat retina, which was ameliorated in rats pretreated with AH23848. Serum VEGF-A was upregulated in the PGE2-treated diabetic rats vs non-treated diabetic rats and significantly downregulated in AH23848-treated diabetic rats. PGE2 or cay10598 treatment also significantly accelerated endothelial tip-cell formation in new-born rat retina. In addition, AH23848 treatment attenuated PGE2-or cay10598-induced proliferation and migration by repressing the EGF receptor (EGFR)/Growth factor receptor bound protein 2-associated binder protein 1 (Gab1)/Akt/NF-κB/VEGF-A signaling network in human retinal microvascular endothelial cells (hRMECs). PGE2/EP4R signaling network is thus a potential therapeutic target for pathological intraocular angiogenesis.

Identification of prognostic alternative splicing signatures in uveal melanoma.

PURPOSE: Alternative splicing (AS) events were reportedly associated with the development of multiple cancers. The study was designed to provide a comprehensive analysis of AS events and explore their potential prognostic value in uveal melanoma (UM). METHODS: The prognostic AS events, identified based on the data of 80 UM patients obtained from The Cancer Genome Atlas, were further screened and analyzed for construction of prognostic signatures by using LASSO regression and multivariate Cox model. Kaplan-Meier survival analysis was used to evaluate the prognostic value. The AS events-related functional pathways were explored by gene set enrichment analysis (GSEA). The difference between two subgroups in terms of treatment options was investigated. The regulatory network between prognostic AS events and splicing factors (SFs) was then constructed. RESULTS: A total of 1014 AS events were identified as prognostic AS events. Five prognostic AS events were involved in the construction of prognostic signatures, including AKAP2/87175/AP, RGMA/32575/ES, DNASE1L1/90581/ES, BIN1/55198/ES and ERCC2/50430/AT. UM patients were then divided into two subgroups. Prognostic AS signatures had an excellent performance in predicting the survival of UM patients, with an area under curve (AUC) of 0.962. GSEA results suggested several splicing-associated mechanisms, including cellular metabolic process and apoptosis. Low-risk subgroup could be more sensitive to drugs. A higher expression of immune checkpoint genes was observed in high-risk group than in low-risk group. SFs-AS regulatory network also revealed significant association between AS events and SFs. CONCLUSIONS: Aberrant AS events in UM patients might serve as prognostic predictors.

Altered Corneal Nerves in Chinese Thyroid-Associated Ophthalmopathy Patients Observed by In Vivo Confocal Microscopy.

BACKGROUND Thyroid-associated ophthalmopathy (TAO) is a common endocrine autoimmune disease. The present study explored corneal nerve changes in TAO patients. MATERIAL AND METHODS Thirty-eight Chinese TAO patients and 20 healthy individuals were included in the study. Central corneal subbasal nerve density and morphology were evaluated with in vivo laser scanning confocal microscopy and quantified using automated CCmetrics software. RESULTS The values of the central corneal subbasal nerve plexus parameters of both active and inactive TAO patients were significantly decreased compared with those of controls, including corneal nerve fiber density (CNFD) (P<0.001 for both), corneal nerve branch density (CNBD) (P<0.001 for both), corneal nerve fiber length (CNFL) (P<0.001 for both), corneal nerve fiber total branch density (CTBD) (P<0.001 for both), corneal nerve fiber area (CNFA) (P<0.001 for both), corneal nerve fiber width (CNFW) (P=0.046, P=0.027, respectively), and corneal nerve fiber fractal dimension (ACNFrD) (P<0.001 for both). In addition, CNFD and ACNFrD values were significantly lower in the active TAO patients compared with those in the inactive TAO patients (P=0.020, P=0.002, respectively). There were significant correlations between CNFD, CNBD, CNFL, CTBD, CNFA, and ACNFrD and the ocular surface parameters and activity assessment items. CONCLUSIONS Abnormal corneal subbasal nerves were observed in both active and inactive Chinese TAO patients, suggesting that nerve degeneration is associated with the disease. However, the exact underlying mechanisms remain to be elucidated.

CD40 ligand induces expression of vascular cell adhesion molecule 1 and E-selectin in orbital fibroblasts from patients with Graves' orbitopathy.

PURPOSE: The aim of this study was to detect the effect of the CD40 ligand (CD40L) on the expression of vascular cell adhesion molecule 1 (VCAM-1) and E-Selectin in orbital fibroblasts (OFs) from patients with Graves' orbitopathy (GO), as well as the signaling pathways involved in this effect. METHODS: OFs were isolated from orbital tissues obtained from patients with severe GO who were undergoing orbital decompression surgery. VCAM-1 and E-selectin RNA and protein expression levels were quantified in OFs stimulated with soluble CD40L (sCD40L). RNA and protein quantification was performed with real-time polymerase chain reaction (PCR) and western blot analysis. Cytoplasmic and nuclear fractions were isolated in order to detect the nuclear translocation of nuclear factor-κB (NF-κB). Signaling pathway inhibitors were applied to determine the pathways involved. RESULTS: Compared to unstimulated OFs, the mRNA and protein levels of VCAM-1 and E-selectin in OFs incubated with sCD40L were significantly increased. This was observed in dose- and time-course experiments, and the inductive effects of sCD40L were much weaker in OFs from healthy donors. At the same time, we observed that CD40L induced nuclear translocation of NF-κB, also in a dose- and time-dependent manner. The up-regulation of VCAM-1 and E-selectin, as well as the NF-κB nuclear translocation induced by CD40L, was significantly attenuated by inhibitors targeting mitogen-activated protein kinases (MAPKs), phosphatidylinositol 3-kinase (PI3K), and NF-κB. CONCLUSIONS: CD40L demonstrated the ability to up-regulate the expression of VCAM-1 and E-selectin at the pre-translational level in OFs from patients with GO. The MAPK and PI3K pathways and NF-κB may play important roles in CD40L-induced VCAM-1 and E-selectin expression.

Meta-analysis of association between the -2578C/A polymorphism of the vascular endothelial growth factor and retinopathy in type 2 diabetes in Asians and Caucasians.

BACKGROUND AND OBJECTIVES: Vascular endothelial growth factor (VEGF) has been shown to play an important role in the development and progress of diabetic retinopathy (DR). A number of case-control studies focused on the association between VEGF -2578C/A and risk for DR. But the results were not always consistent, so we performed a meta-analysis to evaluate the precise association between this variant and risk for DR. METHODS: All publications on the association between VEGF -2578C/A polymorphism and DR were searched in the following electronic databases: PubMed, Embase, the Cochrane Library and Chinese Biomedical Literature Database, with the last report up to January 2013. This meta-analysis was assessed by Review Manager 5.1. RESULTS: A total of 6 studies were involved in this meta-analysis, including 835 cases and 867 controls. Overall, we found a significant association between this polymorphism and DR (A vs. C: OR=1.49, 95% CI=1.26-1.77, p<0.00001; AA vs. CA+CC: OR=1.26, 95% CI=0.94-1.68, p=0.12; AA+CA vs. CC: OR=1.56, 95% CI=1.27-1.91, p<0.00001; AA vs. CC: OR=1.67, 95% CI=1.20-2.32, p=0.003; CA vs. CC: OR=1.51, 95% CI=1.21-1.87, p=0.0002), but we did not find any significant association in Caucasians in subgroup analysis. The results were not materially altered after the studies which did not fulfill the Hardy-Weinberg equilibrium were excluded. CONCLUSION: Our meta-analysis supports the association between the VEGF -2578C/A polymorphism and DR, but not in the Caucasian population.

YAP O-GlcNAcylation contributes to corneal epithelial cell ferroptosis under cigarette smoke exposure.

Cigarette smoke (CS) is an important indoor air pollutant associated with an increased risk of ocular surface disease. As the eye's outermost layer, the cornea is highly sensitive to air pollutants like CS. However, the specific mechanisms linking CS exposure to corneal dysfunction have not been fully elucidated. In the present study, we found that CS exposure damages corneal epithelial cells, accompanied by increased iron (Fe2+) levels and lipid peroxidation, both hallmarks of ferroptosis. Ferroptosis inhibitors, including Ferrostatin-1 (Fer-1) and Deferoxamine mesylate (DFO), protect against CS-induced cell damage. To understand the underlying mechanisms, we investigated how CS affects iron and lipid metabolism. Our results showed that CS could upregulate intracellular iron levels by increasing TFRC expression and promote lipid peroxidation by increasing ACSL4 expression. Silencing ACSL4 or TFRC expression prevented CS-induced ferroptosis. Furthermore, we found that the upregulation of TFRC and ACSL4 was driven by increased YAP transcription. Pharmacological or genetic inhibition of YAP effectively prevented corneal epithelial cell ferroptosis under CS stimulation. Additionally, our results suggest that CS exposure could increase O-GlcNAc transferase activity, leading to YAP O-GlcNAcylation. This glycosylation of YAP interfered with its K48-linked ubiquitination, resulting in YAP stabilization. Collectively, we found that CS exposure induces corneal epithelial cell ferroptosis via the YAP O-GlcNAcylation, and provide evidence that CS exposure is a strong risk factor for ocular surface disease.

The prevalence of visual impairment in older adults in mainland China: a systematic review and meta-analysis.

PURPOSE: This paper presents estimates of the prevalence of blindness and low vision among older adults over 50 years of age in mainland China. METHODS: All primary reports of population-based studies that reported the prevalence or incidence of visual impairment among older populations in mainland China were identified. Twenty-four population-based studies were included in this systematic review. Blindness is defined as visual acuity of less than 3/60, or a corresponding visual-field loss to less than 10 degrees in the better eye with the best possible correction; low vision is defined as visual acuity of less than 6/18, but equal to or better than 3/60 in the better eye with the best possible correction. The pooled prevalence estimates of blindness and low vision were calculated assuming a random-effects model. Relative odds with 95% confidence intervals (95% CIs) were calculated, stratified by methodological and socioeconomic variables. RESULTS: The overall pooled prevalence of blindness was 1.7% (95% CI 1.4-2.1). The results of the meta-regression showed the significance of a predictor variable: geographic region. The blindness rates per 100 older adults in various regions were 1.4 (0.9-2.0) in East China, and 1.4 (1.0-2.0) in Central China and 2.5 (1.9-3.2) in Western China. The overall pooled prevalence of low vision was 4.1% (3.4-5.1) and the independent pooled prevalence rates stratified by geographic region were 3.6% (2.6-5.1) in East China, 3.6% (2.4-5.2) in Central China and 5.2% (3.6-7.4) in Western China. CONCLUSIONS: Blindness or low vision affects approximately 5.8% Chinese adults older than 50 years. The prevalence of visual impairment, and especially blindness, vary greatly by the developmental status of geographic region.

Iron derived from NCOA4-mediated ferritinophagy causes cellular senescence via the cGAS-STING pathway.

Cellular senescence is a hallmark of aging and has been linked to age-related diseases. Age-related macular degeneration (AMD), the most common aging-related retinal disease, is prospectively associated with retinal pigment epithelial (RPE) senescence. However, the mechanism of RPE cell senescence remains unknown. In this study, tert-butyl hydroperoxide (TBH)-induced ARPE-19 cells and D-galactose-treated C57 mice were used to examine the cause of elevated iron in RPE cell senescence. Ferric ammonium citrate (FAC)-treated ARPE-19 cells and C57 mice were used to elucidated the mechanism of iron overload-induced RPE cell senescence. Molecular biology techniques for the assessment of iron metabolism, cellular senescence, autophagy, and mitochondrial function in vivo and in vitro. We found that iron level was increased during the senescence process. Ferritin, a major iron storage protein, is negatively correlated with intracellular iron levels and cell senescence. NCOA4, a cargo receptor for ferritinophagy, mediates degradation of ferritin and contributes to iron accumulation. Besides, we found that iron overload leads to mitochondrial dysfunction. As a result, mitochondrial DNA (mtDNA) is released from damaged mitochondria to cytoplasm. Cytoplasm mtDNA activates the cGAS-STING pathway and promotes inflammatory senescence-associated secretory phenotype (SASP) and cell senescence. Meanwhile, iron chelator Deferoxamine (DFO) significantly rescues RPE senescence and retinopathy induced by FAC or D-gal in mice. Taken together, these findings imply that iron derived from NCOA4-mediated ferritinophagy causes cellular senescence via the cGAS-STING pathway. Inhibiting iron accumulation may represent a promising therapeutic approach for age-related diseases such as AMD.

Differentially expressed genes in orbital adipose/connective tissue of thyroid-associated orbitopathy.

Background: Thyroid-associated orbitopathy (TAO) is a disease associated with autoimmune thyroid disorders and it can lead to proptosis, diplopia, and vision-threatening compressive optic neuropathy. To comprehensively understand the molecular mechanisms underlying orbital adipogenesis in TAO, we characterize the intrinsic molecular properties of orbital adipose/connective tissue from patients with TAO and control individuals. Methods: RNA sequencing analysis (RNA-seq) was performed to measure the gene expression of orbital adipose/connective tissues of TAO patients. Differentially expressed genes (DEGs) were detected and analyzed through Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, and Gene Set Enrichment Analysis (GSEA). The protein-protein interaction (PPI) network was constructed using the STRING database, and hub genes were identified by the Cytoscape plug-in, cytoHubba. We validated several top DEGs through quantitative real-time polymerase chain reaction (qRT-PCR). Results: We identified 183 DEGs in adipose tissue between TAO patients (n = 3) and control patients (n = 3) through RNA sequencing, including 114 upregulated genes and 69 downregulated genes. The PPI network of these DEGs had 202 nodes and 743 edges. PCR-based validation results of orbital adipose tissue showed multiple top-ranked genes in TAO patients (n = 4) are immune and inflammatory response genes compared with the control individual (n = 4). They include ceruloplasmin isoform x3 (CP), alkaline tissue-nonspecific isozyme isoform x1 (ALPL), and angiotensinogen (AGT), which were overrepresented by 2.27- to 6.40-fold. Meanwhile, protein mab-21-like 1 (MAB21L1), phosphoinositide 3-kinase gamma-subunit (PIK3C2G), and clavesin-2 (CLVS2) decreased by 2.6% to 32.8%. R-spondin 1 (RSPO1), which is related to oogonia differentiation and developmental angiogenesis, was significantly downregulated in the orbital muscle tissues of patients with TAO compared with the control groups (P = 0.024). Conclusions: Our results suggest that there are genetic differences in orbital adipose-connective tissues derived from TAO patients. The upregulation of the inflammatory response in orbital fat of TAO may be consistent with the clinical phenotype like eyelid edema, exophthalmos, and excess tearing. Downregulation of MAB21L1, PIK3C2G, and CLVS2 in TAO tissue demonstrates dysregulation of differentiation, oxidative stress, and developmental pathways.

Long Noncoding RNA PPT2-EGFL8 Regulates Pathological Retinal Neovascularization in PDR by Functioning as a Competing Endogenous RNA.

Diabetic retinopathy (DR) is a common complication in patients with diabetes, and proliferative DR (PDR) has become an important cause of blindness; however, the mechanisms involved have not been fully elucidated. miRNAs and long noncoding RNAs can play an important role in DR, and they can accurately regulate the expression of target genes through a new regulatory model: competing endogenous RNAs. We isolated total RNA of extracellular vesicles (EVs) in the serum of healthy individuals and individuals with diabetes without DR, non-PDR, or PDR, and performed deep sequencing. We found aberrantly low expression of PPT2-EGFL8 and significantly increased level of miR-423-5p. PPT2-EGFL8 adsorbs miR-423-5p as a molecular sponge and inhibits hypoxia-induced human retinal microvascular endothelial cells proliferation. In an oxygen-induced retinopathy (OIR) model and a streptozotocin-induced diabetes model, Egfl8-overexpression treatment reduces diabetes-related reactive gliosis, inflammation, and acellular capillaries and attenuates the development of pathological neovascularization. In addition, PPT2-EGFL8 targeting miR-423-5p plays an important role in hypoxia-induced peroxisome proliferator-activated receptor-ß/δ (PPARD)/angiopoietin-like 4 (ANGPTL4) signaling activation, especially the expression of the C-terminal ANGPTL4 fragment. Finally, ANGPTL4 significantly induces retinal vessel breakage in the inner limiting membrane and facilitates retinal vessel sprouting into the vitreous in the OIR mice. Thus, either new biomarkers or new therapeutic targets may be identified with translation of these findings.

MiR-423-5p promotes Müller cell activation via targeting NGF signaling in diabetic retinopathy.

AIMS: Diabetic retinopathy (DR) is a common microvascular complication of diabetes mellitus and one of the major causes of visual impairment and blindness in industrialized countries. The early neuro-glial perturbations, especially retinal Müller cells (rMC) activation, intimately associated with the vascular alterations. MicroRNAs (miRNAs) have been reported to play critical roles in the progression of DR. Here, we aimed to further explore the role and underlying mechanism of miR-423-5p in Müller cell activation in streptozotocin (STZ)-induced diabetic mice and oxygen-induced retinopathy (OIR) model. MATERIALS AND METHODS: Retinal histology, optical coherence tomography (OCT) and biochemical markers were assessed. KEY FINDINGS: Our data revealed that the expression of miR-423-5p was significantly increased under high-glucose environment. We also demonstrated that miR-423-5p overexpression markedly accelerated retinal vascular leakage, leukocytosis, and rMC activation. This response was ameliorated in animals pre-treated with the inhibition of miR-423-5p. Specifically, miR-423-5p bound to the nerve growth factor (NGF) 3' UTR region to induce its silencing. NGF inhibition significantly promoted retinal microvascular dysfunction. SIGNIFICANCE: These findings demonstrate that miR-423-5p is a critical miRNA that promotes microvascular dysfunction in DR.

MicroRNA-200 is commonly repressed in conjunctival MALT lymphoma, and targets cyclin E2.

BACKGROUND: Aberrant microRNA expression is implicated in cancer initiation and progression. We sought to identify dysregulated miRNAs in conjunctival mucosa-associated lymphoid tissue (MALT) lymphoma, and investigated their biological significance. METHODS: The profiles of miRNAs in conjunctival MALT lymphoma and normal adjacent tissues were investigated by microRNA microarray of four pairs of surgically removed conjunctival MALT lymphoma tissues and matched controls. The results of microarray were further confirmed in 14 paired conjunctival MALT lymphoma samples (including the former four pairs) using quantitative RT-PCR. The functional effect of miR-200 was examined further. A luciferase reporter assay was performed to confirm the predicted target. RESULTS: The microarray results revealed upregulated miR-150/155, and downregulated miR-184, miR-200a, b, c, and miR-205. These findings were confirmed by quantitative RT-PCR. Targetscan analysis suggested cyclin E2 as potential target of miR-200a, b, c. Luciferase reporter assay using vectors containing the 3'UTR of cyclin E2 showed that miR-200a, b, c could suppress luciferase activities. RT-PCR and immunoblotting studies revealed that overexpression of miR-200a, b, c reduced the mRNA and protein levels of cyclin E2 respectively. CONCLUSIONS: We demonstrated that miRNAs were dysregulated in conjunctival MALT lymphoma, and dysregulation of the miR-200 family could be involved in the pathogenesis and progression of the disease.

Lack of association of conjunctival MALT lymphoma with Chlamydiae or Helicobacter pylori in a cohort of Chinese patients.

BACKGROUND: This study was conducted to detect microbial pathogens in conjunctival mucosa-associated lymphoid tissue (MALT) lymphoma specimens in an attempt to determine possible associations between conjunctival MALT lymphoma and microbial infections. MATERIAL/METHODS: Using PCR technique, freshly obtained tumor specimens from 16 cases of conjunctival MALT lymphoma, as confirmed by postoperative pathology, were analyzed for DNA of Chlamydia psittaci (C. psittaci), Chlamydia trachomatis (C. trachomatis), Chlamydia pneumoniae (C. pneumoniae) and Helicobacter pylori (H. pylori). Synthetic C. psittaci, C. trachomatis, C. pneumoniae and H. pylori DNA were used as positive control, and blank plasmid DNA as negative control. RESULTS: Electrophoresis showed that no bands corresponding to the positive control were observed in the specimens, indicating that no DNA of the 4 microorganisms was detected in the specimens of the 16 cases of conjunctival MALT lymphoma. CONCLUSIONS: The PCR technique was able to detect the positive control quickly and accurately, but the results of PCR in analyzing the 16 specimens were negative, indicating that there is no association between conjunctival MALT lymphoma and the 4 microorganisms in Chinese patients.

[Analysis of clinical features in distensible orbital venous malformations].

OBJECTIVE: To study the characteristic of the clinical and image features of distensible orbital venous malformations (DOVM). METHODS: It was a retrospective case series study. Clinical features and imaging findings, including B ultrasonography, CDFI, MRI, CT imaging of 43 patients with DOVM were reviewed in Shanghai Changzheng Hospital affiliated to Secondary Military Medical University RESULTS: Forty-three patients (24 women and 19 men), whose ages range from 5 to 71 years old, showed clinical or radiological evidence of distensibility. The mean age was 32 years. Location of the lesion within the orbit was variable, 9 patients with superficial lesions, and 19 patients with deep lesions. Twelve patients were classified as combined lesions. 3 patients with extraorbital venous malformations were classified as complex lesions. Twenty of 43 patients with DOVM were initially seen with proptosis or pain increasing with the head in a dependent position. Eight patients presented with a sudden onset of proptosis and pain secondary to thrombosis or hemorrhage. B ultrasonography showed an intermittently anechoic lesion that exhibits intrinsic flow during the Valsalva maneuver. Color Doppler imaging might demonstrate a reversal of flow toward the transducer during the Valsalva maneuver. Thirty-five of 43 cases with axial CT images showed a normal appearance or only mild enlargement of the involved veins, but coronal CT images could clearly demonstrate the lesion distensibility. Eight cases showed well defined tumor with homogeneous high density due to the thrombosis or hemorrhage within the orbit. MR imaging showed hypo to hyperintense signal on T(1)-weighted images, had hyperintense signal on T(2)-weighted MR images. However, signal of lesions of orbital hemorrhage could be various according to the different hemorrhage time. CONCLUSION: DOVM usually occurs in young patients. Clinical diagnosis can be established with the typical symptoms and one or more imaging examinations.

Tetramethylpyrazine inhibits the proliferation, invasiveness and migration of cervical cancer C33A cells by retarding the Hedgehog signaling pathway.

Cervical carcinoma (CC) ranks among the top four most common cancers in women worldwide. Over the last 10 years, several studies have confirmed the inhibitory effects of tetramethylpyrazine (TMP) on numerous types of cancer. To investigate the inhibitory effect of TMP on the CC C33A cell line, MTT and colony formation assays were performed to determine how TMP affects C33A cell survival and proliferation. Proliferation-, migration- and hedgehog (Hh) signaling pathway-related protein expression levels were analyzed via western blotting. Wound-healing and Transwell assays were used to detect the migration and invasion abilities of C33A cells, respectively. The results indicated that TMP markedly reduced the C33A cell survival rate compared with the cervical epithelial Ect1 cell line, which was unaffected by TMP treatment. C33A cell proliferation was downregulated by TMP treatment in a dose-dependent manner. TMP treatment also significantly inhibited C33A cell migration and invasiveness in a dose-dependent manner. Furthermore, TMP inhibited the Hh signaling pathway, as demonstrated by a dose-dependent reduction in Hh-related protein expression levels following TMP treatment. Subsequently, treatment with smoothened agonist increased the proliferation, invasiveness and migration abilities of TMP-treated C33A cells. In conclusion, TMP inhibited the proliferation, migration and invasiveness of CC cells via inhibition of the Hh signaling pathway.

Decorin Protects Retinal Pigment Epithelium Cells from Oxidative Stress and Apoptosis via AMPK-mTOR-Regulated Autophagy.

Age-related macular degeneration (AMD) is the leading cause of irreversible visual loss among the elderly worldwide with unidentified pathogenesis and limited therapeutic options. Oxidative stress-induced damage to the retinal pigment epithelium (RPE) is central in the development and progression of AMD. Decorin (DCN), a small leucine-rich proteoglycan, possesses powerful antifibrotic, anti-inflammatory, and antiangiogenic properties. DCN has also been reported to serve a cytoprotective role in various cell types, but its protective effects against H2O2-induced oxidative stress and apoptosis in ARPE-19 cells remain unclear. In this study, we showed that DCN significantly attenuated the increase in cell viability loss, apoptosis rate, and reactive oxygen species (ROS) levels in ARPE-19 cells induced by H2O2. Furthermore, DCN activated the AMPK/mTOR pathway to promote autophagy while genetic inhibition of autophagy-related gene 5 (ATG5) hindered autophagic process and diminished the protective role of DCN against oxidative stress in ARPE-19 cells. Collectively, these results suggest that DCN could protect RPE cells from H2O2-induced oxidative stress and apoptosis via autophagy promotion, thus providing the therapeutic potential for AMD prevention and treatment.