Canagliflozin ameliorates the development of NAFLD by preventing NLRP3-mediated pyroptosis through FGF21-ERK1/2 pathway

Abstract

Recent studies have suggested that sodium-glucose co-transporter2 inhibitors go beyond their glycemic advantages to ameliorate the development of NAFLD. However, little research has been done on the underlying mechanisms. Here, we took deep insight into the effect of canagliflozin (CANA), one of the sodium-glucose co-transporter2 inhibitor, on the progression of NAFLD, and explored the molecular mechanisms. Our findings showed that CANA-treated ob/ob and diabetic mice developed improved glucose and insulin tolerance, although their body weights were comparable or even increased compared with the controls. The CANA treatment ameliorated hepatic steatosis and lipid accumulation of free fatty acid–treated AML12 cells, accompanied by decreased lipogenic gene expression and increased fatty acid β oxidation–related gene expression. Furthermore, inflammation and fibrosis genes decreased in the livers of CANA-treated ob/ob and diabetic mice mice. FGF21 and its downstream ERK1/2/AMPK signaling decreased, whereas NLRP3-mediated pyroptosis increased in the livers of the ob/ob and diabetic mice mice, which was reversed by the CANA treatment. In addition, blocking FGF21 or ERK1/2 activity antagonized the effects of CANA on NLRP3-mediated pyroptosis in lipopolysaccharide plus nigericin-treated J774A.1 cells. We conclude that CANA treatment alleviated insulin resistance and the progression of NAFLD in ob/ob and diabetic mice mice independent of the body weight change. CANA protected against the progression of NAFLD by inhibiting NLRP3-mediated pyroptosis and enhancing FGF21-ERK1/2 pathway activity in the liver. These findings suggest the therapeutic potential of sodium-glucose co-transporter2 inhibitors in the treatment of NAFLD.