DataSheet7_Sanqi Oral Solution Mitigates Proteinuria in Rat Passive Heymann Nephritis and Blocks Podocyte Apoptosis via Nrf2/HO-1 Pathway.ZIP

Idiopathic membranous nephropathy (IMN) is the most common pathological type in adult nephrotic syndrome where podocyte apoptosis was found to mediate the development of proteinuria. Sanqi oral solution (SQ), an effective Chinese herbal preparation clinically used in treatment of IMN for decades, plays an important role in reducing proteinuria, but the underlying mechanisms have not been fully elucidated yet. The current study tested the hypothesis that SQ directly lessens proteinuria in IMN by reducing podocyte apoptosis. To investigate the effects of SQ, we established the experimental passive Heymann nephritis (PHN) rat model induced by anti-Fx1A antiserum in vivo and doxorubicin hydrochloride (ADR)-injured apoptotic podocyte model in vitro. SQ intervention dramatically reduced the level of proteinuria, together with the rat anti-rabbit IgG antibodies, complement C3, and C5b-9 deposition in glomerulus of PHN rats, accompanied by an elevation of serum albumin. Protein expression of synaptopodin, marker of podocyte injury, restored after SQ administration, whereas the electron microscopic analysis indicated that fusion of foot processes, and the pachynsis of glomerular basement membrane was markedly diminished. Further studies showed that SQ treatment could significantly inhibit podocyte apoptosis in PHN rats and ADR-injured podocytes, and protein levels of Cleaved Caspase-3 or the ratio of Bax/Bcl-2 were significantly decreased with SQ treatment in vivo or in vitro. Moreover, we found that the nuclear factor erythroid 2–related factor-2/heme oxygenase 1 (Nrf2/HO-1) pathway mediated the anti-apoptosis effective of SQ in podocyte. Thus, SQ mitigates podocyte apoptosis and proteinuria in PHN rats via the Nrf2/HO-1 pathway.

特发性膜性肾病（Idiopathic membranous nephropathy, IMN）是成人肾病综合征最常见的病理类型，现有研究证实足细胞凋亡可介导蛋白尿的发生与进展。三七口服液（Sanqi oral solution, SQ）是一款临床应用数十年治疗IMN的有效中药制剂，其在减少蛋白尿方面疗效确切，但具体作用机制尚未完全阐明。本研究旨在验证如下假说：SQ可通过减轻足细胞凋亡，直接改善IMN相关蛋白尿。为探究SQ的生物学效应，本研究分别构建了体内抗Fx1A抗血清诱导的实验性被动海曼肾炎（passive Heymann nephritis, PHN）大鼠模型，以及体外盐酸多柔比星（doxorubicin hydrochloride, ADR）损伤的凋亡足细胞模型。结果显示，SQ干预可显著降低PHN大鼠的蛋白尿水平，同时减少大鼠抗兔IgG抗体、补体C3及C5b-9在肾小球的沉积，并可升高血清白蛋白浓度。足细胞损伤标志物突触足蛋白（synaptopodin）的蛋白表达水平在SQ给药后得以恢复；电子显微镜分析进一步显示，足突融合及肾小球基底膜增厚的病理改变均得到显著改善。后续机制研究表明，SQ治疗可显著抑制PHN大鼠及ADR损伤足细胞的凋亡；体内外实验均证实，SQ处理可显著降低裂解型半胱氨酸天冬氨酸蛋白酶3（Cleaved Caspase-3）的蛋白表达水平，并下调Bax/Bcl-2比值。此外，本研究发现核因子E2相关因子2/血红素氧合酶1（nuclear factor erythroid 2–related factor-2/heme oxygenase 1, Nrf2/HO-1）通路介导了SQ对足细胞的抗凋亡保护作用。综上，SQ可通过激活Nrf2/HO-1通路，减轻PHN大鼠的足细胞凋亡与蛋白尿水平。