Celastrol alleviates SGLT2 inhibitor-induced diabetic hyperketonemia by inhibiting hepatic ketogenesis.

SGLT2 inhibitor (SGLT2i)-induced diabetic hyperketonemia is a life-threatening acute complication of diabetes. While celastrol has been reported to have beneficial effects on obesity, its potential role in ketogenesis remains unclear. In this study, celastrol administration significantly attenuates the fasting-induced increase in blood β-hydroxybutyrate levels. Moreover, a 7-day course of celastrol (1 mg/kg/day) leads to reductions in body weight and fat mass. Mechanistically, celastrol specifically downregulates HMGCS2 expression and suppresses hepatic ketogenesis through the inhibition of PPARα expression in the short term (≤ 2 days). However, after prolonged treatment for 7 days, celastrol modulates both PPARα and serum free fatty acid (FFA) levels. Furthermore, the anti-ketogenic effect of celastrol is abolished in Pparα -/- mice. Importantly, celastrol effectively ameliorates SGLT2i-induced hyperketonemia. In summary, celastrol curbs hepatic ketone overproduction in a PPARα-dependent manner, indicating its protective potential against SGLT2i-induced hyperketonemia.