Chronic C75 treatment of diet-induced obese mice increases fat oxidation and reduces food intake to reduce adipose mass

Departments of 1 Pathology, 2 Neuroscience, 3 Psychiatry, 4 Neurology, 5 Oncology, and 6 Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 Submitted 12 June 2003 ; accepted in final form 16 January 2004 Obesity and its attendant disorders, such as type 2 diabetes, are global health problems. We previously reported that C75, an inhibitor of fatty acid synthase (FAS) and stimulator of carnitine palmitoyltransferase I (CPT I), caused anorexia and profound weight loss in lean and genetically obese mice. To approximate human obesity, we utilized a chronic C75 treatment model for diet-induced obese (DIO) mice. Chronic C75 treatment decreased food consumption and increased energy expenditure due to increased fatty acid oxidation in both DIO and lean mice. There was a substantial loss of adipose tissue and resolution of hepatic steatosis in C75-treated DIO mice. Analysis of changes in the expression of hypothalamic neuropeptides demonstrated that the reduced food consumption in C75-treated DIO mice was accompanied by an increase in cocaine and amphetamine-related transcript expression but not by changes in neuropeptide Y such as seen with acute C75 treatment of lean mice. Inhibition of FAS and stimulation of CPT I provide a means to achieve stable, sustained weight loss in DIO mice. fatty acid synthase; carnitine palmitoyltransferase I; neuropeptide Y Address for reprint requests and other correspondence: F. P. Kuhajda, Johns Hopkins Univ. School of Medicine, Bldg. AA, Rm. 154A, 4940 Eastern Ave., Baltimore, MD 21224 (E-mail: fkuhajda{at}jhmi.edu ).