Ginsenoside Rb1 alleviates 3-MCPD-induced renal cell pyroptosis by activating mitophagy

Ginsenoside Rb1 (Gs-Rb1) is among the most significant effective pharmacological components in ginseng. 3-Monochloropropane-1,2-diol (3-MCPD), a chloropropanol-like contaminant, is produced in the production of refined oils and thermal processing of food. Pyroptosis is a type of programmed cell death triggered by inflammasomes. Excessive Pyroptosis causes kidney injury and inflammation. Previous studies have revealed that 3-MCPD induced Pyroptosis in mice and NRK-52E cells. In the present study, we find that Gs-Rb1 attenuates 3-MCPD-induced renal cell Pyroptosis by assaying GSDMD-N, Caspase-1, IL-18, and IL-1β in mice and NRK-52E cells. In further mechanistic studies, we show that Gs-Rb1 removes damaged mitochondria via Mitophagy and reduces intracellular Reactive Oxygen Species (ROS) generation, therefore alleviating 3-MCPD-induced NOD-like receptor family pyrin domain containing 3 (NLRP3) activation and Pyroptosis. The above results are further validated by the addition of Autophagy Inhibitor Chloroquine (CQ) and Mitophagy inhibitor Cyclosporin A (CsA). Afterward, we explore how Gs-Rb1 activated Mitophagy in vitro. We determine that Gs-Rb1 enhances the protein expression and nuclear translocation of Transcription factor EB (TFEB). However, silencing of the TFEB gene by small interfering RNA technology reverses the role of Gs-Rb1 in activating Mitophagy. Therefore, we conclude that 3-MCPD damages mitochondria and leads to ROS accumulation, which causes NLRP3 activation and Pyroptosis in ICR mice and NRK-52E cells, while Gs-Rb1 mitigates this phenomenon via the TFEB-mitophagy pathway. Our findings may provide new insights for understanding the molecular mechanisms by which Gs-Rb1 mitigates renal injury.

3-monochloropropane-1,2-diol; Ginsenoside Rb1; Mitophagy; Pyroptosis; Renal injury; TFEB.