Wang Ruixin, Yan Yuehong, Li Cuicui
Department of Nephrology, The Fifth Affiliated Hospital of Guangzhou Medical University, 621 Gangwan Road, Huangpu District, Guangzou, Guangdong, 510730, P.R. China.
Cell Biol Int. 2020 Jan;44(1):286-294. doi: 10.1002/cbin.11231. Epub 2019 Sep 23.
New evidences suggest that long non-coding RNAs (lncRNAs) may play important roles in a variety of kidney diseases, including diabetic nephropathy (DN). Our present study investigated the potential function of LINC00462 in high glucose (HG)-induced apoptosis of renal tubular epithelial cells (RTEC) and to determine the underlying mechanism. The expression of LINC00462 in renal biopsy tissues was examined using quantitative reverse-transcription polymerase chain reaction (qRT-PCR). Then, a loss of function assay was performed to determine the protective effect of LINC00462 in HG-induced RTEC damage. In addition, the downstream signaling pathway of LINC00462 was also investigated. The qRT-PCR results showed that the expression of LINC00462 was significantly up-regulated in renal biopsies from DN patients. At the same time, LINC00462 was enhanced in a glucose concentration- and time-dependent manner in human kidney (HK-2 and HKC) cells subjected to HG treatment. The knockdown of LINC00462 improved the significantly reduced cell viability of HG treatment, decreased HG-induced reactive oxygen species (ROS) and malondialdehyde levels, and up-regulated the response of antioxidant systems to ROS by increasing superoxide dismutase and catalase levels. In addition, knockdown of LINC00462 inhibited HG-induced cell apoptosis and affected the expression of apoptosis-related proteins. Most importantly, we found that knockdown of LINC00462 enhanced the expression of p-AKT. Moreover, AKT-specific inhibitor LY294002 restored the effect of LINC00462 knockdown on apoptosis. In conclusion, our study demonstrated that knockdown of LINC00462 can ameliorate oxidative stress and apoptosis in HG-induced RTEC by activating the AKT pathway, suggesting that knockdown of LINC00462 may provide a potential therapeutic approach for DN.
新证据表明，长链非编码RNA（lncRNA）可能在包括糖尿病肾病（DN）在内的多种肾脏疾病中发挥重要作用。我们目前的研究调查了LINC00462在高糖（HG）诱导的肾小管上皮细胞（RTEC）凋亡中的潜在功能，并确定其潜在机制。使用定量逆转录聚合酶链反应（qRT-PCR）检测肾活检组织中LINC00462的表达。然后，进行功能丧失试验以确定LINC00462对HG诱导的RTEC损伤的保护作用。此外，还研究了LINC00462的下游信号通路。qRT-PCR结果显示，DN患者肾活检组织中LINC00462的表达显著上调。同时，在接受HG处理的人肾（HK-2和HKC）细胞中，LINC00462以葡萄糖浓度和时间依赖性方式增强。敲低LINC00462可改善HG处理后显著降低的细胞活力，降低HG诱导的活性氧（ROS）和丙二醛水平，并通过增加超氧化物歧化酶和过氧化氢酶水平上调抗氧化系统对ROS的反应。此外，敲低LINC00462可抑制HG诱导的细胞凋亡并影响凋亡相关蛋白的表达。最重要的是，我们发现敲低LINC00462可增强p-AKT的表达。此外，AKT特异性抑制剂LY294002恢复了LINC00462敲低对凋亡的影响。总之，我们的研究表明，敲低LINC00462可通过激活AKT途径改善HG诱导的RTEC中的氧化应激和凋亡，提示敲低LINC00462可能为DN提供一种潜在的治疗方法。
