James M. Ntambi

Steenbock Professor of Nutritional Sciences
Professor of Biochemistry
B.S. 1975, Makerere University, Kampala Uganda
Msc. 1978, Makerere University Kampala Uganda
Ph.D. 1985, Johns Hopkins University School of Medicine

Emphasis Group:
Biochemical and Molecular Nutrition

Research Interests:
Genetic Regulation of Metabolism Nutrient gene interactions

Research Summary: 
We are interested in the genetic basis of obesity and diabetes and how the metabolism of dietary factors influences these disease states.

In particular we study the regulation of the mammalian stearoyl-CoA desaturase (SCD) genes that encode an enzyme involved in the biosynthesis of monounsaturated fatty acids. We are using these genes as a model to understand nutrient gene interactions.

We have recently genetically engineered mice that are born without the stearoyl-CoA desaturase gene I and found that these mice resist obesity, diabetes, fatty liver disease and other aspects of the metabolic syndrome. Our research is being extended to humans.

Representative Publications

Cohen, P., Ntambi, J. M. and Friedman, J. M.  Stearoyl-CoA desaturase-1 and the metabolic syndrome.  Curr. Drug Targets Immune Endocr. Metabol. Disord. 3, 271-280 (2003).

Dobrzyn, P., Dobrzyn, A., Miyazaki, M., Cohen, P., Asilmaz, E., Hardie, D. G., Friedman, J. M. and Ntambi, J. M.  Stearoyl-CoA desaturase-1 deficiency increases fatty acid oxidation by activating AMP-activated protein kinase in liver.  Proc. Natl. Acad. Sci. USA 101, 6409-6414 (2004). 

Hulver, M. W., Berggren, J. R., Carper, M. J., Miyazaki, M., Ntambi, J. M., Hoffman, E. P., Thyfault, J. P., Stevens, R., Dohm, G. L., Houmard, J. A. and Muoio, D. M.  Elevated stearoyl-CoA desaturase-1 expression in skeletal muscle contributes to abnormal fatty acid partitioning in obese humans.  Cell Metab. 2, 251-261 (2005). 

Ntambi, J. M.  Lipids, genes, and health.  Science 312, 698 (2006). 

Flowers, M. T., Miyazaki, M., Liu, X. and Ntambi, J. M.  Probing the role of stearoyl CoA desaturase-1 in hepatic insulin resistance.  J. Clin. Invest. 116, 1478-1481 (2006). 

Sampath H, Miyazaki M, Dobrzyn A, Ntambi JM.  Stearoyl CoA desaturase-1 mediates the pro-lipogenic effects of dietary saturated fat. J Biol Chem. 282: 2483-93 (2007)