Pimozide Alleviates Hyperglycemia in Diet-Induced Obesity by Inhibiting Skeletal Muscle Ketone Oxidation

• DOI: 10.1016/j.cmet.2020.03.017
• Publication Date: 2020-04-09T14:31:12Z
• Authors: Rami Al Batran; Keshav Gopal; Megan E. Capozzi; Jadin J. Chahade; Bruno Saleme; S. Amirhossein Ta...; Amanda A. Greenwell; Jingjing Niu; Malak Almutairi; Nikole J. Byrne; Grant Masson; Ryekjang Kim; Farah Eaton; Erin E. Mulvihill; Léa Garneau; Andrea R. Masters; Zeruesenay Desta; Carlos A. Velázqu...; Céline Aguer; Peter A. Crawford; Gopinath Sutendra; Jonathan E. Campbell; Jason R.B. Dyck; John R. Ussher
• Keywords: Pimozide

Perturbations in carbohydrate, lipid, and protein metabolism contribute to obesity-induced type 2 diabetes (T2D), though whether alterations in ketone body metabolism influence T2D pathology is unknown. We report here that activity of the rate-limiting enzyme for ketone body oxidation, succinyl-CoA:3-ketoacid-CoA transferase (SCOT/Oxct1), is increased in muscles of obese mice. We also found that the diphenylbutylpiperidine pimozide, which is approved to suppress tics in individuals with Tourette syndrome, is a SCOT antagonist. Pimozide treatment reversed obesity-induced hyperglycemia in mice, which was phenocopied in mice with muscle-specific Oxct1/SCOT deficiency. These actions were dependent on pyruvate dehydrogenase (PDH/Pdha1) activity, the rate-limiting enzyme of glucose oxidation, as pimozide failed to alleviate hyperglycemia in obese mice with a muscle-specific Pdha1/PDH deficiency. This work defines a fundamental contribution of enhanced ketone body oxidation to the pathology of obesity-induced T2D, while suggesting pharmacological SCOT inhibition as a new class of anti-diabetes therapy.