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71.
目的:探究microRNA-152-3p(miR-152-3p)靶向胰岛素样生长因子1(IGF1)基因对高糖诱导的视网膜色素上皮ARPE-19细胞活性和凋亡的影响,并探讨其作用机制。
方法:高糖诱导ARPE-19细胞并转染miR-152-3p mimics,噻唑蓝(MTT)法检测细胞增殖活性,流式细胞术检测细胞凋亡情况,荧光定量PCR(RT-PCR)检测细胞中miR-152-3p水平,蛋白印迹(Western blot)法检测细胞中IGF1和VEGF表达水平,双荧光素酶报告基因检测IGF1和miR-152-3p靶向结合关系。
结果:高糖能够降低ARPE-19细胞活性,提高细胞凋亡率,抑制细胞中miR-152-3p的表达,提高IGF1和VEGF的表达; 而过表达miR-152-3p能够回调高糖诱导的细胞活性抑制及凋亡增加,抑制IGF1和VEGF的表达。双荧光素酶报告基因实验验证了IGF1是miR-152-3p的靶基因。
结论:miR-152-3p可通过靶向IGF1基因调节VEGF的表达抑制高糖诱导的ARPE-19细胞活性抑制和凋亡增加。 相似文献
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Reactive oxygen species mediates a metabolic memory of high glucose stress signaling in bovine retinal pericytes 下载免费PDF全文
AIM: To investigate the role of reactive oxygen species (ROS) and antioxidant mechanism underlying the metabolic memory of bovine retinal pericytes (BRPs) induced by high glucose.
METHODS: Effects of high glucose levels and culture time on BRPs viability were evaluated by CCK-8. BRPs were grown in high-glucose media (30 mmol/L) for 4d followed by culture in normal glucose condition (5.6 mmol/L) for 4d in an experimental group. In contrast, in negative and positive control groups, BRPs were grown in either normal-glucose media or high-glucose media for 8d, respectively. The ROS levels, apoptosis, the expression and activity of manganese superoxide dismutase (MnSOD) in BRPs, as well as the protective effect of adeno-associated viral (AAV)-mediated over expression of MnSOD were determined separately by DCHFA, ELISA and Western blot.
RESULTS: Comparing the result of cells apoptosis, activity and protein expression of MnSOD and caspase-3, the cell culture system that exposed in sequence in 30 mmol/L and normal glucose for 4d was demonstrated as a suitable model of metabolic memory. Furthermore, delivery of antioxidant gene MnSOD can decrease BRPs apoptosis, reduce activated caspase-3, and reverse hyperglycemic memory by reducing the ROS of mitochondria.
CONCLUSION: Increased ROS levels and decreased MnSOD levels may play important roles in pericyte loss of diabetic retinopathy. BRPs cultured in high glucose for 4d followed by normal glucose for 4d could be an appropriate model of metabolic memory. rAAV-MnSOD gene therapy provides a promising strategy to inhibit this blinding disease. 相似文献
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Diabetic retinopathy (DR) is one of the leading causes of vision loss and can be effectively avoided by screening, early diagnosis and treatment. In order to increase the universality and efficiency of DR screening, many efforts have been invested in developing intelligent screening, and there have been great advances. In this paper, we survey DR screening from four perspectives: 1) public color fundus image datasets of DR; 2) DR classification and related lesion-extraction approaches; 3) existing computer-aided systems for DR screening; and 4) existing issues, challenges, and research trends. Our goal is to provide insights for future research directions on DR intelligent screening. 相似文献
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糖尿病视网膜病变(DR)是糖尿病最常见和最严重的微血管并发症之一,其基本病理改变是血.视网膜屏障破坏及新生血管形成.目前DR的防治由以往的控制危险因素、单一提高胰岛素的降糖作用等简单原则,发展到调节葡萄糖代谢、增加胰岛素受体敏感性、抑制胰岛素抵抗及糖基化终末产物的形成、减少氧化应激等多方面.本文综述血糖控制、特殊治疗药物和中医药早期防治等用于DR内科治疗的药物的开发进展. 相似文献
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Guang-Hua Zhang Guang-Ping Zhuo Zhao-Xia Zhang Bin Sun Wei-Hua Yang Shao-Chong Zhang 《国际眼科》2024,17(7):1193-1204
AIM: To address the challenges of data labeling difficulties, data privacy, and necessary large amount of labeled data for deep learning methods in diabetic retinopathy (DR) identification, the aim of this study is to develop a source-free domain adaptation (SFDA) method for efficient and effective DR identification from unlabeled data.
METHODS: A multi-SFDA method was proposed for DR identification. This method integrates multiple source models, which are trained from the same source domain, to generate synthetic pseudo labels for the unlabeled target domain. Besides, a softmax-consistence minimization term is utilized to minimize the intra-class distances between the source and target domains and maximize the inter-class distances. Validation is performed using three color fundus photograph datasets (APTOS2019, DDR, and EyePACS).
RESULTS: The proposed model was evaluated and provided promising results with respectively 0.8917 and 0.9795 F1-scores on referable and normal/abnormal DR identification tasks. It demonstrated effective DR identification through minimizing intra-class distances and maximizing inter-class distances between source and target domains.
CONCLUSION: The multi-SFDA method provides an effective approach to overcome the challenges in DR identification. The method not only addresses difficulties in data labeling and privacy issues, but also reduces the need for large amounts of labeled data required by deep learning methods, making it a practical tool for early detection and preservation of vision in diabetic patients. 相似文献