Lu Hai-Tao, Jiao Yuan-Yuan, Yu Tian-Yu, Shi Jing-Xuan, Tian Jing-Wei, Zou Gu-Ming, Liu Lin, Zhuo Li
Department of Nephrology, China-Japan Friendship Hospital, Beijing, China.
Department of Nephrology, Fuwai Hospital, Chinese Academy of Medical Science, Beijing, China.
Front Pharmacol. 2024 Mar 19;15:1344113. doi: 10.3389/fphar.2024.1344113. eCollection 2024.
Diabetic kidney disease (DKD) necessitates innovative therapeutic strategies. This study delves into the role of DNA damage-inducing transcription factor 4 (DDIT4) within the VDR-mTOR pathway, aiming to identify a novel target for DKD drug discovery.
Transcriptome data from the Gene Expression Omnibus Database were analyzed to assess the expression of mTOR and VDR expression in human renal tissues. Clinical samples from DKD patients and minimal change disease (MCD) controls were examined, and a DKD animal model using 20-week-old db/db mice was established. DDIT4 plasmid transfection was employed to modulate the VDR-mTOR pathway, with its components evaluated using immunohistochemistry, real-time quantitative PCR (qRT-PCR), Western blotting, and enzyme-linked immunosorbent assay (ELISA).
Changes in the expression of the VDR-mTOR pathway were observed in both DKD patients and the animal model. Overexpression of DDIT4 increased VDR expression and decreased levels of mTOR, p70s6k, and 4E-BP1. Furthermore, DDIT4 treatment regulated autophagy by upregulating LC3I expression and downregulating LC3II expression. Notably, DDIT4 alleviated oxidative stress by reducing the levels of lipid peroxidation product MDA, while simultaneously increasing the levels of superoxide dismutase (SOD) and glutathione (GSH), underscoring the role of DDIT4 in the pathological process of DKD and its potential as a therapeutic target.
Unraveling DDIT4's involvement in the VDR-mTOR pathway provides insights for innovative DKD drug discovery, emphasizing its potential as a therapeutic target for future interventions.
糖尿病肾病(DKD)需要创新的治疗策略。本研究深入探讨DNA损伤诱导转录因子4(DDIT4)在维生素D受体(VDR)-雷帕霉素靶蛋白(mTOR)通路中的作用,旨在确定DKD药物研发的新靶点。
分析基因表达综合数据库中的转录组数据,以评估人肾组织中mTOR和VDR的表达。检测DKD患者和微小病变病(MCD)对照的临床样本,并建立使用20周龄db/db小鼠的DKD动物模型。采用DDIT4质粒转染来调节VDR-mTOR通路,通过免疫组织化学、实时定量聚合酶链反应(qRT-PCR)、蛋白质免疫印迹法和酶联免疫吸附测定(ELISA)对其成分进行评估。
在DKD患者和动物模型中均观察到VDR-mTOR通路表达的变化。DDIT4的过表达增加了VDR的表达,并降低了mTOR、p70核糖体蛋白S6激酶(p70s6k)和真核细胞起始因子4E结合蛋白1(4E-BP1)的水平。此外,DDIT4处理通过上调微管相关蛋白1轻链3I(LC3I)的表达和下调微管相关蛋白1轻链3II(LC3II)的表达来调节自噬。值得注意的是,DDIT4通过降低脂质过氧化产物丙二醛(MDA)的水平来减轻氧化应激,同时增加超氧化物歧化酶(SOD)和谷胱甘肽(GSH)的水平,突出了DDIT4在DKD病理过程中的作用及其作为治疗靶点的潜力。
阐明DDIT4在VDR-mTOR通路中的作用为创新的DKD药物研发提供了思路,强调了其作为未来干预治疗靶点的潜力。