Department of Nephrology, Radboud Institute for Molecular Life Sciences (RIMLS), Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands.
Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC 3800, Australia.
Int J Mol Sci. 2021 Nov 19;22(22):12485. doi: 10.3390/ijms222212485.
Increased expression and activity of the Ca channel transient receptor potential channel 6 (TRPC6) is associated with focal segmental glomerulosclerosis, but therapeutic strategies to target TRPC6 are currently lacking. Nitric oxide (NO) is crucial for normal glomerular function and plays a protective role in preventing glomerular diseases. We investigated if NO prevents podocyte injury by inhibiting injurious TRPC6-mediated signaling in a soluble guanylate cyclase (sGC)-dependent manner and studied the therapeutic potential of the sGC stimulator Riociguat. Experiments were performed using human glomerular endothelial cells and podocytes. Podocyte injury was induced by Adriamycin incubation for 24 h, with or without the NO-donor S-Nitroso-N-acetyl-DL-penicillamine (SNAP), the sGC stimulator Riociguat or the TRPC6 inhibitor Larixyl Acetate (LA). NO and Riociguat stimulated cGMP synthesis in podocytes, decreased Adriamycin-induced TRPC6 expression, inhibited the Adriamycin-induced TRPC6-mediated Ca influx and reduced podocyte injury. The protective effects of Riociguat and NO were blocked when sGC activity was inhibited with 1H-[1,2,4]Oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) or when TRPC6 activity was inhibited by LA. Our data demonstrate a glomerular (e)NOS-NO-sGC-cGMP-TRPC6 pathway that prevents podocyte injury, which can be translated to future clinical use by, e.g., repurposing the market-approved drug Riociguat.
钙通道瞬时受体电位通道 6（TRPC6）表达和活性增加与局灶节段性肾小球硬化有关，但目前缺乏靶向 TRPC6 的治疗策略。一氧化氮（NO）对正常肾小球功能至关重要，在预防肾小球疾病方面发挥着保护作用。我们研究了 NO 是否通过以可溶性鸟苷酸环化酶（sGC）依赖的方式抑制有害的 TRPC6 介导的信号来防止足细胞损伤，并研究了 sGC 刺激剂 Riociguat 的治疗潜力。实验使用人肾小球内皮细胞和足细胞进行。用阿霉素孵育 24 小时诱导足细胞损伤，同时或不使用 NO 供体 S-亚硝基-N-乙酰-DL-青霉胺（SNAP）、sGC 刺激剂 Riociguat 或 TRPC6 抑制剂 Larixyl Acetate（LA）。NO 和 Riociguat 刺激足细胞中环鸟苷酸（cGMP）的合成，降低阿霉素诱导的 TRPC6 表达，抑制阿霉素诱导的 TRPC6 介导的 Ca2+内流，并减少足细胞损伤。当 sGC 活性被 1H-[1,2,4]恶二唑[4,3-a]喹喔啉-1-酮（ODQ）抑制或当 TRPC6 活性被 LA 抑制时，Riociguat 和 NO 的保护作用被阻断。我们的数据表明存在一种肾小球（e）NOS-NO-sGC-cGMP-TRPC6 途径，可以防止足细胞损伤，例如通过重新利用市售药物 Riociguat，可以将其转化为未来的临床应用。
