The Chinese herbal medicine Fufang Zhenzhu Tiaozhi protects against diabetic cardiomyopathy by alleviating cardiac lipotoxicity-induced oxidative stress and NLRP3-dependent inflammasome activation

BACKGROUND: Fufang Zhenzhu Tiao Zhi (FTZ) formula is a Chinese herbal preparation used in the clinical treatment of disorders of glucolipid metabolism. Given its effective actions on the regulation of lipid dysfunction and its anti-inflammatory and antioxidative effects, we designed this study to investigate the cardioprotective effect and possible mechanism of FTZ in diabetic cardiomyopathy (DCM) mice. METHODS: FTZ was administered to diabetic mice by oral gavage daily at a dose of 1.2 g/kg or 2.4 g/kg bodyweight for 8 weeks. Doppler echocardiography, H&E, and WGA staining were used to evaluate cardiac function and structure in the mice. The levels of proinflammatory cytokines and lipids in serum were detected with corresponding commercial kits. Immunofluorescence staining and flow cytometry were used to detect oxidation damage and pyroptosis in myocardial cells. RT-PCR and western blotting were used to analyze the protein and mRNA expression levels of NLRP3 inflammasome-related genes. RESULTS: Our study indicated that FTZ improved cardiac function, attenuated heart hypertrophy, improved serum lipid and proinflammatory cytokine levels, and restrained oxidative stress and NLRP3 inflammasome-induced inflammatory activities in diabetic mouse hearts. The in vitro data suggested that FTZ suppressed intercellular lipid accumulation as well as palmitic acid (PA)-induced oxidative stress and NLRP3 inflammasome-dependent pyroptosis in cardiomyocytes. CONCLUSION: Our present findings indicate that FTZ inhibits DCM by inhibiting both oxidative stress and NLRP3 inflammasome activation induced by cardiac lipotoxicity.