Department of Pharmacology, College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China; Hanlin College, Nanjing University of Chinese Medicine, Taizhou 225300, China.
Hanlin College, Nanjing University of Chinese Medicine, Taizhou 225300, China.
Life Sci. 2020 Sep 15;257:118120. doi: 10.1016/j.lfs.2020.118120. Epub 2020 Jul 18.
Catalpol (Cat) can ameliorate oxide stress and inflammation caused by diabetic nephropathy (DN), but the molecular mechanisms are unclear. This study was designed to investigate the anti-diabetic effects of Cat and its potential mechanism.
We constructed high-fat diet/streptozotocin (HFD/STZ)-induced DN mice and high glucose (HG)-induced podocyte model. The hypoglycemic effect of Cat was analyzed by general features of DN mice. Kidney function was detected via ELISA assay and Western blotting. Renal histopathology analysis was conducted via hematoxylin and eosin (H&E), Masson and periodic acid-silver metheramine (PASM) staining. Cellular viability was measured by TUNEL assay. In order to further study the potential mechanisms of Cat, various proteins in AMPK/SIRT1/NF-κB pathway were detected in DN mice and podocytes with siRNA-AMPK intervention using Western blotting, respectively.
We found hyperglycemia, renal structural and function abnormalities, and increased renal inflammation in DN mice. However, Cat effectively attenuated kidney damage caused by inflammation and increased AMPK, p-AMPK and SIRT1 levels. After AMPK-siRNA transfected into HG-induced podocyte model, AMPK, p-AMPK and SIRT1 levels were obviously decreased, while Cat reversed these chandes. The levels of p-NF-κB, ASC, Cleaved IL-1β, NLRP3, Cleaved caspase1 and GSDMD-N significantly decreased by Cat treatment both in DN mice and podocyte model, which indicated that Cat could activate AMPK/SIRT1/NF-κB pathway.
Cat could effectively inhibit oxide stress and inflammation accompanied with pyroptosis and its mechanism might be related to AMPK/SIRT1/NF-κB pathway, indicating that Cat possessed potential value in the treatment of DN.
梓醇（Cat）可改善糖尿病肾病（DN）引起的氧化应激和炎症，但具体的分子机制尚不清楚。本研究旨在探讨 Cat 的抗糖尿病作用及其潜在机制。
构建高脂肪饮食/链脲佐菌素（HFD/STZ）诱导的 DN 小鼠和高糖（HG）诱导的足细胞模型。通过 DN 小鼠的一般特征分析 Cat 的降血糖作用。通过 ELISA 检测和 Western blot 检测肾功。通过苏木精和伊红（H&E）、Masson 和过碘酸-希夫（PASM）染色进行肾组织病理学分析。通过 TUNEL 检测评估细胞活力。为了进一步研究 Cat 的潜在机制，分别通过 Western blot 检测 DN 小鼠和 siRNA-AMPK 干预的足细胞中 AMPK/SIRT1/NF-κB 通路中的各种蛋白。
我们发现 DN 小鼠存在高血糖、肾脏结构和功能异常以及炎症增加。然而，Cat 有效减轻了炎症引起的肾脏损伤，并增加了 AMPK、p-AMPK 和 SIRT1 水平。在将 AMPK-siRNA 转染到 HG 诱导的足细胞模型后，AMPK、p-AMPK 和 SIRT1 水平明显降低，而 Cat 逆转了这些变化。Cat 处理后，DN 小鼠和足细胞模型中 p-NF-κB、ASC、Cleaved IL-1β、NLRP3、Cleaved caspase1 和 GSDMD-N 的水平显著降低，表明 Cat 可以激活 AMPK/SIRT1/NF-κB 通路。
Cat 能有效抑制氧化应激和炎症伴发的细胞焦亡，其机制可能与 AMPK/SIRT1/NF-κB 通路有关，提示 Cat 在治疗 DN 方面具有潜在价值。
