Methamphetamine induces cardiomyopathy by Sigmar1 inhibition-dependent impairment of mitochondrial dynamics and function

Methamphetamine-associated cardiomyopathy is the leading cause of death linked with illicit drug use. Here we show that Sigmar1 is a therapeutic target for methamphetamine-associated cardiomyopathy and defined the molecular mechanisms using autopsy samples of human hearts, and a mouse model of binge and crash methamphetamine administration. Sigmar1 expression is significantly decreased in the hearts of human methamphetamine users and those of binge and crash methamphetamine-treated mice. The hearts of methamphetamine users also show signs of cardiomyopathy, including cellular injury, fibrosis, and enlargement of the heart. In addition, mice expose to binge and crash methamphetamine develop cardiac hypertrophy, fibrotic remodeling, and mitochondrial dysfunction leading to contractile dysfunction. Methamphetamine treatment inhibits Sigmar1, resulting in inactivation of the cAMP response element-binding protein (CREB), decreased expression of mitochondrial fission 1 protein (FIS1), and ultimately alteration of mitochondrial dynamics and function. Therefore, Sigmar1 is a viable therapeutic agent for protection against methamphetamine-associated cardiomyopathy. Chowdhury Abdulla and Richa Aishwarya et al. report that methamphetamine exposure in mice leads to cardiomyopathy via the signaling receptor Sigmar1. They find that methamphetamine inhibits Sigmar1, which alters mitochondrial function, and show that their findings are consistent with observations in hearts from human methamphetamine users.