Type 2 diabetes mellitus (T2DM) is one of the most important risk factors for nonalcoholic fatty liver disease (NAFLD), including nonalcoholic steatohepatitis (NASH). Thus far, there are no approved medicines to treat NAFLD/NASH and none of plasma biomarkers are sufficient to accurately and rapidly diagnose NASH in clinic. Canagliflozin is a sodium-glucose cotransporter 2 inhibitor that not only reduces glycemia, blood pressure and albuminuria, but also lowers body weight and improves dyslipidemia. However, whether canagliflozin can be used to treat NAFLD/NASH and its impacts on lipid and lipoprotein metabolism are still rather obscure. Based on findings from the previous studies, the investigators propose the following hypothesis: canagliflozin decreases body fat mass, in particular the visceral fat depots and liver fat content, thus alleviating hepatic steatosis, hepatic macrophage content and activation. Since the investigators have demonstrated for the first time that plasma cholesteryl ester transfer protein (CETP) is predominantly derived from hepatic macrophages, and CETP plays a pivotal role in regulating lipid and lipoprotein metabolism. Moreover, plasma CETP concentration and activity can be applied as an effective biomarker for hepatic steatosis and liver inflammation and damage. Collectively, in this study, 80 patients with T2DM combined with NAFLD, who have poor glycemic control response to metformin monotherapy, will be randomly assigned to receive canagliflozin or pioglitazone (as placebo control) on top of metformin. The primary outcome will be plasma CETP concentration and activity, as measurements of liver lipid content, hepatic steatosis, liver inflammation and damage. The secondary outcome will be nuclear magnetic resonance spectroscopy- based metabolomics, including lipoprotein profile, lipid species and metabolomic, to comprehensively evaluate the therapeutic effects of canagliflozin on lipids and lipoproteins. The investigators anticipate this prospective, randomized controlled intervention study will reveal the potential clinical application and underlying mechanisms of canagliflozin in the treatment of NAFLD/NASH, and also provide a theoretical basis for predicting its effect on cardiovascular disease events, thus having important economic value and scientific significance.
Type 2 diabetes mellitus (T2DM) is always accompanied with nonalcoholic fatty liver disease (NAFLD).This prospective, randomized controlled intervention study was designed to reveal the potential clinical application and underlying mechanisms of canagliflozin in the treatment of type 2 diabetes combined with nonalcoholic fatty liver disease.