Jia Tianqi, Guo Yujia, Zhao Xiaolong
Department of Ophthalmology, Harbin Bright Eye Hospital, No.563 Xianfeng Road, Nangang District, Harbin, 150000, China.
Department of Ophthalmology, Fengtai District Hospital of Traditional Chinese Medicine, No.3 Nanyuan CCBA Hutong, Fengtai District, Beijing, 100076, China.
J Mol Histol. 2024 Dec 27;56(1):58. doi: 10.1007/s10735-024-10337-8.
Chronic oxidative stress (COS) is related to the pathophysiology of the trabecular meshwork (TM) in glaucoma. MicroRNAs (miRNAs) have a key role in the oxidative stress-mediated glaucoma. This work investigated the function of miR-126-5p in human trabecular meshwork cells (TMCs) under chronic oxidative stress (COS). The miR-126-5p inhibitor was transfected into TMCs to assess the function of miR-126-5p. The targets of miR-126-5p were predicted by bioinformatic analysis. A luciferase assay was applied to test the relationship between miR-126-5p and its target. Cell proliferation was assessed using MTT. Flow cytometry and TUNEL were used for the assessment of apoptosis. We found that the miR-126-5p level was elevated in TMCs exposed to COS. MiR-126-5p inhibitor markedly promoted TMC proliferation and inhibited the increases in apoptosis and extracellular matrix (ECM) proteins induced by COS. Heat shock protein B8 (HSPB8) was identified to be targeted by miR-126-5p. MiR-126-5p inhibitor restored the expression level of HSPB8 in TMCs under COS. Additionally, miR-126-5p depletion activated PI3K/AKT signaling in TMCs by upregulating HSPB8. HSPB8 downregulation or LY294002 treatment prevented the effects mediated by miR-126-5p inhibition on apoptosis and ECM in COS-treated TMCs. Overall, silencing miR-126-5p protects TMCs against COS-induced injury by upregulating HSPB8 to activate PI3K/AKT signaling.
慢性氧化应激（COS）与青光眼小梁网（TM）的病理生理学相关。微小RNA（miRNA）在氧化应激介导的青光眼中起关键作用。本研究调查了慢性氧化应激（COS）条件下miR-126-5p在人小梁网细胞（TMCs）中的功能。将miR-126-5p抑制剂转染到TMCs中以评估miR-126-5p的功能。通过生物信息学分析预测miR-126-5p的靶标。应用荧光素酶报告基因检测来测试miR-126-5p与其靶标的关系。使用MTT评估细胞增殖。采用流式细胞术和TUNEL法评估细胞凋亡。我们发现暴露于COS的TMCs中miR-126-5p水平升高。miR-126-5p抑制剂显著促进TMC增殖，并抑制COS诱导的细胞凋亡增加和细胞外基质（ECM）蛋白增加。热休克蛋白B8（HSPB8）被鉴定为miR-126-5p的靶标。miR-126-5p抑制剂可恢复COS条件下TMCs中HSPB8的表达水平。此外，miR-126-5p缺失通过上调HSPB8激活TMCs中的PI3K/AKT信号通路。HSPB8下调或LY294002处理可阻止miR-126-5p抑制对COS处理的TMCs中细胞凋亡和ECM的影响。总体而言，沉默miR-126-5p通过上调HSPB8激活PI3K/AKT信号通路来保护TMCs免受COS诱导的损伤。
