Polygala fallax Hemsl. ameliorated high glucose-induced podocyte injury by modulating mitochondrial mPTP opening through the SIRT1/PGC-1α pathway.

This study aimed to investigate the effects and molecular mechanism of PF on high glucose (HG)-induced podocyte injury. Results found that PF increased proliferation activity, decreased apoptosis, LDH, and caspase-3 levels, and increased nephrin and podocin expression in HG-induced cells. Similarly, PF improved HG-induced mitochondrial damage, decreased Ca²⁺ and ROS content, alleviated oxidative stress, inhibited mPTP opening, increased mitochondrial membrane potential, and decreased the expressions of Drp1, Bak, Bax, and Cytc in cytoplasm, increased the expressions of SIRT1, PGC-1α, HSP70, HK2, and Cytc in mitochondria of podocytes. The use of mPTP agonist/blocker and SIRT1 inhibitor confirmed that PF alleviates HG-induced podocyte injury by regulating mitochondrial mPTP opening through SIRT1/PGC-1α. In addition, PF affected HK2-VDAC1 protein binding to regulate mPTP opening via the SIRT1/PGC-1α pathway. In conclusion, PF-regulated HK2-VDAC1 protein binding affected mitochondrial mPTP opening and improved HG-induced podocyte injury through the SIRT1/PGC-1α pathway.