KRAS depletion suppresses ferroptosis and affects Hippo pathway in cataract.

Cataract, a painless and progressive disorder is manifested as the opacification of the lens that represents the most significant cause of blindness worldwide. The objective of this study is to unveil the function of Kirsten rat sarcoma (KRAS) and potential action mechanisms against cataract. The ferroptosis-associated differentially expressed genes (DEGs) and pivot genes were extracted through the comprehensive bioinformatics methods. Erastin was applied for inducing ferroptosis in hydrogen peroxide (H2O2)-treated SRA01/04 cells, and validated by detecting content of intracellular iron, glutathione (GSH), malondialdehyde (MDA). Additionally, the effects of KRAS deficiency on ferroptosis were determined by functional assays. The proteins expression related to ferroptosis and Hippo pathway were determined by Western blotting. A total of 73 ferroptosis-related DEGs were discovered, and 6 critical core genes were confirmed upregulation in cataract cell model. The H2O2-treated SRA01/04 cells exhibited decrease of cell viability and proliferation, iron accumulation, MDA increase, GSH consumption, rise of COX2 and decline of GPX4, with further aggravated under erastin treatment, while the phenomena were improved by KRAS knockdown. Additionally, KRAS deficiency was involved in the Hippo signalling pathway activation. Downregulation of KRAS might restrain ferroptosis and affect Hippo pathway in cataract.

MicroRNA-93 promotes the pathogenesis of glaucoma by inhibiting matrix metalloproteinases as well as up-regulating extracellular matrix and Rho/ROCK signaling pathways.

Objective: To investigate the effect and potential molecular mechanism of microRNA-93 (miR-93) on retinal ganglion cells (RGCs) apoptosis as well as retinal damage in acute glaucoma mice. Methods: RGCs apoptosis were induced by oxygen-glucose deprivation and reperfusion (OGD/R). The pro-apoptotic effect of miR-93 was evaluated by transfecting miR-93 mimics or miR-93 inhibitor into OGD/R-induced RGCs. The viability and apoptosis of RGCs were determined by MTT assay and flow cytometry. Mouse model of acute glaucoma were successfully induced via high intraocular pressure (IOP), and then these model animals were randomly divided into vehicle group, miR-93 mimics group or miR-93 inhibitor group (n = 10), using healthy mice as normal control. Histopathologic changes of retinal tissue were evaluated by Hematoxylin and Eosin (H&E) staining method. Moreover, cell counts of retinal ganglion cell layer and mean thickness of different layers were also determined. Quantitative real-time PCR (qPCR) and western blotting analysis were used to detect the mRNA and protein expression levels of extracellular matrix (ECM), matrix metalloproteinases (MMPs) and Rho/ROCK signaling pathway. Results: miR-93 mimics significantly decreased or promoted the viability and apoptosis of OGD/R-induced RGCs, respectively. In addition, miR-93 mimics significantly exacerbated the degree of retinal tissue damage in mice with acute glaucoma, which was accompanied by a decrease in the number of ganglion cell layer (GCL) cells and the thickness of different tissue layers. Moreover, miR-93 mimics significantly increased IOP in mice with acute glaucoma. Significantly, miR-93 inhibitors significantly reversed the above changes. In addition, results of Western blot analysis showed that miR-93 mimics increased and decreased the expression of ECM-associated and MMP-associated proteins, respectively, by activating the Rho/ROCK signaling pathway. In contrast, miR-93 significantly decreased and increased the expression of ECM-associated and MMP-associated proteins, and suppressed the expression of Rho/ROCK signaling pathway-related proteins. Conclusion: miR-93 can promote the development of glaucoma by activating Rho/ROCK signaling pathway to mediate the accumulation of ECM-related proteins as well as the down-regulation of MMP-related proteins.

Circ_0080940 Regulates miR-139-5p/CTGF Pathway to Promote the Proliferation, Migration, Extracellular Matrix Deposition of Human Tenon's Capsule Fibroblasts.

PURPOSE: Circular RNA (circRNA) has been identified as an important regulator for glaucoma progression. Our study aims to reveal the circ_0080940 roles in glaucoma progression. METHODS: Transforming growth factor ß1 (TGF-ß1) was used to treat human Tenon's capsule fibroblasts (HTFs) to mimic glaucoma cell models. Cell function was determined by cell counting kit 8 assay, EdU assay and wound healing assay. Protein levels were determined by western blot analysis. Quantitative real-time PCR was used to measure RNA expression. Dual-luciferase reporter assay was performed to evaluate RNA interaction. RESULTS: Our data confirmed that TGF-ß1 induced HTFs proliferation, migration and extracellular matrix (ECM) deposition. Circ_0080940 was highly expressed in glaucoma patients, and its knockdown inhibited TGF-ß1-induced proliferation, migration and ECM deposition in HTFs. Circ_0080940 sponged miR-139-5p, and anti-miR-139-5p revoked the effect of si-circ_0080940 on the biological functions of TGF-ß1-induced HTFs. CTGF was targeted by miR-139-5p, and overexpressed CTGF overturned the inhibition effect of miR-139-5p on the biological functions of TGF-ß1-induced HTFs. Furthermore, CTGF expression could be positively regulated by circ_0080940. CONCLUSION: To sum up, we confirmed that circ_0080940 contributed to glaucoma progression by miR-139-5p/CTGF axis.

A novel missense mutation of FOXC1 in an Axenfeld-Rieger syndrome patient with a congenital atrial septal defect and sublingual cyst: a case report and literature review.

BACKGROUND: Axenfeld-Rieger syndrome (ARS) is a rare autosomal dominant hereditary disease characterized primarily by maldevelopment of the anterior segment of both eyes, accompanied by developmental glaucoma, and other congenital anomalies. FOXC1 and PITX2 genes play important roles in the development of ARS. CASE PRESENTATION: The present report describes a 7-year-old boy with iris dysplasia, displaced pupils, and congenital glaucoma in both eyes. The patient presented with a congenital atrial septal defect and sublingual cyst. The patient's family has no clinical manifestations. Next generation sequencing identified a pathogenic heterozygous missense variant in FOXC1 gene (NM_001453:c. 246C>A, p. S82R) in the patient. Sanger sequencing confirmed this result, and this mutation was not detected in the other three family members. CONCLUSION: To the best of our knowledge, the results of our study reveal a novel mutation in the FOXC1 gene associated with ARS.

Different effects of topical prazosin and pilocarpine on uveoscleral outflow in rabbit eyes.

PURPOSE: To investigate the effects of topical prazosin and pilocarpine on uveoscleral outflow (Fu) in rabbits. METHODS: Sixteen rabbits were randomly divided into the control group (5 rabbits, only topical application of normal salino in the right eye of each rabbit), Prazosin (PZ) treated group (6 rabbits, only 0.1% Prazosin eyedrop 0.1% in the right eye of each one) and Pilocarpine (PC) treated group (5 rabbits, 1% Pilocarpine eye drop in each right eye). Intraocular pressure (IOP) of bilateral eyes of each rabbit was measured before and 1 h after topical application of the eye drop. And the bilateral eyes were perfused with Fluorescein-isothiocyanate bovine serum albumin (FITC-BSA) as the tracer into the anterior chamber of each rabbit for 30 min at 90 min after topical treatment. Then the rabbits were killed for Fu measurement. RESULTS: IOP of PZ-treated eyes decreased [(0.71 +/- 0.07)kPa] in 1 hour after PZ application. IOP of PC-treated eyes decreased [(0.70 +/- 0.08)kPa] in 1 hour after PC application. The average value of Fu was (0.176 +/- 0.048) microliter/min in control eyes. The average value of Fu in PZ-treated eyes was (0.339 +/- 0.018) microliter/min. The average value of Fu in PC-treated eye was (0.123 +/- 0.022) microliter/min. CONCLUSION: Both of PZ and PC can decrease IOP in rabbits following topical application. Topical PZ can increase Fu in rabbits and this is one of the mechanisms of PZ-induced IOP decrease. Topical PC can prevent Fu. PC decreases IOP not through uveoscleral pathway. This study demonstrates that uveoscleral pathway plays an important role in aqueous humor drainage. PZ may be a novel drug for decreasing IOP. FITC-BSA is an effective tracer for studying uveoscleral pathway.