Yuan Li-Sha, Du Hua, Ren Qiu-Yue, Yang Rong-Lu, Liu Shi-Wei, Liu Shi-Yi, Shi Kai-Feng, Wang Bo, Meng Xiang-Fei, Li Tong-Xia, Zhang Ning
Department of Endocrinology and Nephrology, Wangjing Hospital, China Academy of Chinese Medical Sciences, Beijing 100102, China.
Beijing University of Chinese Medicine, Beijing 100029, China.
Evid Based Complement Alternat Med. 2023 Jan 31;2023:3357281. doi: 10.1155/2023/3357281. eCollection 2023.
granules (QHYS), a traditional Chinese herbal medicine formula, have been used in clinical practice for treating diabetic kidney disease for several years by our team. The efficacy of reducing proteinuria and delaying the decline of renal function of QHYS has been proved by our previous studies. However, the exact mechanism by which QHYS exerts its renoprotection remains largely unknown. Emerging evidence suggests that lncRNA MALAT1 is abnormally expressed in diabetic nephropathy (DN) and can attenuate renal fibrosis by modulating podocyte epithelial-mesenchymal transition (EMT).
In the present study, we aimed to explore whether QHYS could modulate lncRNA MALAT1 expression and attenuate the podocyte EMT as well as the potential mechanism related to the Wnt/-catenin signal pathway.
SD rats were fed with the high-fat-high-sucrose diet for 8 weeks and thereafter administered with 30 mg/kg streptozotocin intraperitoneally to replicate the DN model. Quality control of QHYS was performed using high-performance liquid chromatography. QHYS were orally administered at 1.25, 2.5, and 5 g/kg doses, respectively, to the DN model rats for 12 weeks. Body weight, glycated haemoglobin, blood urea nitrogen, serum creatinine, 24-h proteinuria, and kidney index were measured. The morphologic pathology of the kidney was evaluated by Hematoxylin-eosin and Masson's trichrome staining. The expression level of lncRNA MALAT1 was determined by quantitative real-time polymerase chain reaction. In addition, the expression levels of podocyte EMT protein markers and Wnt/-catenin pathway proteins in renal tissues were evaluated by Western blotting and immunohistochemistry.
The results showed that QHYS significantly reduced 24-h proteinuria, blood urea nitrogen, kidney index, and ameliorated glomerular hypertrophy and collagen fiber deposition in the kidney of DN rats. Importantly, QHYS significantly downregulated the expression level of lncRNA MALAT1, upregulated the expression of nephrin, the podocyte marker protein, downregulated the expression of desmin and FSP-1, and mesenchymal cell markers. Furthermore, QHYS significantly downregulated the expression levels of Wnt1, -catenin, and active -catenin.
Conclusively, our study revealed that QHYS significantly reduced proteinuria, alleviated renal fibrosis, and attenuated the podocyte EMT in DN rats, which may be associated with the downregulation of lncRNA MALAT1 expression and inhibition of the Wnt/-catenin pathway.
芪黄益肾颗粒（QHYS）是一种中药复方制剂，多年来一直被本团队用于糖尿病肾病的临床治疗。我们之前的研究已经证实了QHYS在降低蛋白尿和延缓肾功能下降方面的疗效。然而，QHYS发挥肾脏保护作用的确切机制仍不清楚。新出现的证据表明，长链非编码RNA MALAT1在糖尿病肾病（DN）中异常表达，并可通过调节足细胞上皮-间质转化（EMT）来减轻肾纤维化。
在本研究中，我们旨在探讨QHYS是否能够调节长链非编码RNA MALAT1的表达并减轻足细胞EMT，以及与Wnt/β-连环蛋白信号通路相关的潜在机制。
将SD大鼠给予高脂高糖饮食8周，然后腹腔注射30mg/kg链脲佐菌素以复制DN模型。使用高效液相色谱法对QHYS进行质量控制。分别以1.25、2.5和5g/kg的剂量对DN模型大鼠口服QHYS，持续12周。测量体重、糖化血红蛋白、血尿素氮、血清肌酐、24小时蛋白尿和肾脏指数。通过苏木精-伊红染色和Masson三色染色评估肾脏的形态病理学。通过定量实时聚合酶链反应测定长链非编码RNA MALAT1的表达水平。此外，通过蛋白质免疫印迹法和免疫组织化学评估肾组织中足细胞EMT蛋白标志物和Wnt/β-连环蛋白信号通路蛋白的表达水平。
结果显示，QHYS显著降低了DN大鼠的24小时蛋白尿、血尿素氮、肾脏指数，并改善了肾小球肥大和肾脏中的胶原纤维沉积。重要的是，QHYS显著下调了长链非编码RNA MALAT1的表达水平，上调了足细胞标志物蛋白nephrin的表达，下调了波形蛋白和FSP-1以及间充质细胞标志物的表达。此外，QHYS显著下调了Wnt1、β-连环蛋白和活性β-连环蛋白的表达水平。
总之，我们的研究表明，QHYS显著降低了DN大鼠的蛋白尿，减轻了肾纤维化，并减轻了足细胞EMT，这可能与长链非编码RNA MALAT1表达的下调和Wnt/β-连环蛋白信号通路的抑制有关。
