Plamen Penev, M.D., Ph.D.

Intergration of Human Sleep, Fuel and Energy Metabolism

Research Summary

Individual susceptibility to type 2 diabetes is markedly increased in the setting of sedentary living and excessive weight gain. Lifestyle modification combining weight control and regular physical activity can significantly reduce the incidence of type 2 diabetes in high-risk groups. Therefore, the identification of modifiable factors that can interfere with or promote weight maintenance and regular physical activity may facilitate the development of improved strategies for the prevention of type 2 diabetes. Driven by the demands and opportunities of modern life, reduced sleep times are reported by a growing number of Americans and several large epidemiological studies reveal that short or inadequate sleep is associated with obesity and increased incidence of type 2 diabetes. Ongoing experiments in our laboratory also suggest that men and women who gain weight due to overeating and physical inactivity may develop more pronounced abnormalities of glucose metabolism in the presence of recurrent sleep loss. The long-term goal of this line of research is to test the hypothesis that sleep loss has a significant adverse impact on key metabolic and behavioral predictors of type 2 diabetes risk, such as impaired insulin secretion and action, and undesirable changes in the balance between human food intake and energy expenditure.

Selected Papers

Spiegel K, Tasali E, Penev P, Van Cauter E.  Sleep curtailment in healthy young men is associated with decreased leptin levels, elevated ghrelin levels, and increased hunger and appetite. Annals of Internal Medicine, 2004; 141(11): 846-850.

Penev P, Spiegel K, Marcinkowski T, Van Cauter E. Impact of carbohydrate-rich meals on plasma epinephrine levels: dysregulation with aging. Journal of Clinical Endocrinology and Metabolism, 2005; 90(11): 6198-6206.

Penev P. Association between sleep and morning testosterone levels in older men. Sleep, 2007; 30(4): 427-432.

Nedeltcheva A, Kilkus J, Imperial J, Kasza K, Schoeller D, Penev P. Sleep curtailment is accompanied by increased intake of calories from snacks. American Journal of Clinical Nutrition, 2009; 89(1): 126-133.

Nedeltcheva A, Kessler L, Imperial J, Penev P. Exposure to recurrent sleep restriction in the setting of high caloric intake and physical inactivity results in increased insulin resistance and reduced glucose tolerance. Journal of Clinical Endocrinology and Metabolism, 2009; 94(9): 3242-3250. Epub 2009 Jun 30.