Wu Weifeng, Wang Yifan, Li Haidi, Chen Haiyong, Shen Jiangang
School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China.
Chin Med. 2021 Nov 14;16(1):118. doi: 10.1186/s13020-021-00531-1.
Buyang Huanwu Decoction (BHD) is a classical Chinese Medicine formula empirically used for diabetic nephropathy (DN). However, its therapeutic efficacies and the underlying mechanisms remain obscure. In our study, we aim to evaluate the renoprotective effect of BHD on a streptozotocin (STZ)-induced diabetic nephropathy mouse model and explore the potential underlying mechanism in mouse mesangial cells (MCs) treated with high glucose in vitro, followed by screening the active compounds in BHD.
Mice were received 50 mg/kg streptozotocin (STZ) or citrate buffer intraperitoneally for 5 consecutive days. BHD was intragastrically administrated for 12 weeks starting from week 4 after the diabetes induction. The quality control and quantitative analysis of BHD were studied by high-performance liquid chromatography (HPLC). Renal function was evaluated by urinary albumin excretion (UAE) using ELISA. The mesangial matrix expansion and renal fibrosis were measured using periodic acid-schiff (PAS) staining and Masson Trichrome staining. Mouse mesangial cells (MCs) were employed to study molecular mechanisms.
We found that the impaired renal function in diabetic nephropathy was significantly restored by BHD, as indicated by the decreased UAE without affecting the blood glucose level. Consistently, BHD markedly alleviated STZ-induced diabetic glomerulosclerosis and tubulointerstitial injury as shown by PAS staining, accompanied by a reduction of renal inflammation and fibrosis. Mechanistically, BHD inhibited the activation of TGF-β1/Smad3 and NF-κB signaling in diabetic nephropathy while suppressing Arkadia expression and restoring renal Smad7. We further found that calycosin-7-glucoside (CG) was one of the active compounds from BHD, which significantly suppressed high glucose-induced inflammation and fibrosis by inhibiting TGF-β1/Smad3 and NF-κB signaling pathways in mesangial cells.
BHD could attenuate renal fibrosis and inflammation in STZ-induced diabetic kidneys via inhibiting TGF-β1/Smad3 and NF-κB signaling while suppressing the Arkadia and restoring renal Smad7. CG could be one of the active compounds in BHD to suppress renal inflammation and fibrosis in diabetic nephropathy.
补阳还五汤（BHD）是经验性用于治疗糖尿病肾病（DN）的经典中药方剂。然而，其治疗效果及潜在机制仍不清楚。在本研究中，我们旨在评估补阳还五汤对链脲佐菌素（STZ）诱导的糖尿病肾病小鼠模型的肾脏保护作用，并在体外高糖处理的小鼠系膜细胞（MCs）中探索潜在的机制，随后筛选补阳还五汤中的活性成分。
小鼠连续5天腹腔注射50mg/kg链脲佐菌素（STZ）或柠檬酸盐缓冲液。从诱导糖尿病后第4周开始，补阳还五汤灌胃给药12周。采用高效液相色谱法（HPLC）对补阳还五汤进行质量控制和定量分析。通过酶联免疫吸附测定法（ELISA）检测尿白蛋白排泄率（UAE）评估肾功能。采用高碘酸-希夫（PAS）染色和Masson三色染色法测量系膜基质扩张和肾纤维化。采用小鼠系膜细胞（MCs）研究分子机制。
我们发现，补阳还五汤可显著恢复糖尿病肾病受损的肾功能，表现为UAE降低，且不影响血糖水平。同样，PAS染色显示补阳还五汤可显著减轻STZ诱导的糖尿病肾小球硬化和肾小管间质损伤，同时伴有肾脏炎症和纤维化的减轻。机制上，补阳还五汤在糖尿病肾病中抑制TGF-β1/Smad3和NF-κB信号通路的激活，同时抑制Arkadia表达并恢复肾脏Smad7。我们进一步发现毛蕊异黄酮葡萄糖苷（CG）是补阳还五汤中的活性成分之一，其通过抑制系膜细胞中TGF-β1/Smad3和NF-κB信号通路，显著抑制高糖诱导的炎症和纤维化。
补阳还五汤可通过抑制TGF-β1/Smad3和NF-κB信号通路，同时抑制Arkadia并恢复肾脏Smad7，减轻STZ诱导的糖尿病肾脏的肾纤维化和炎症。CG可能是补阳还五汤中抑制糖尿病肾病肾炎症和纤维化的活性成分之一。
