The purpose of our research is to understand how human energy metabolism and physical activity are regulated, and how they impact diseases such as obesity.
My laboratory focuses on human energy metabolism as it relates to health and disease. We have developed advanced techniques such as the whole-room indirect calorimeters (also called respiration or metabolic chambers) that we use to measure the rate of energy expenditure at the minute-by-minute level and substrate oxidation for several hours or for several days. We can also simultaneously measure movement and physiological parameters in this well-controlled environment to study the impacts of physical activities, diets, medications, and environmental temperatures on energy metabolism, heart rate, and hormonal responses. Currently, my laboratory focuses on the cold-induced thermogenesis, brown adipose tissue, muscle and autonomic nervous system activities, and body and skin temperature in response to subtle changes in environmental temperature in different populations. Another area of interest is the effect of pharmacological and dietary interventions on human energy metabolism and obesity. We are also developing new technologies for measuring energy metabolism, body composition, sleep, and physical activity in humans.
The obesity epidemic has increased the general interests in metabolism, physical activity, sleep, and diet. By studying both normal healthy volunteers, subjects who are obese, and patients who have metabolic conditions, we can better understand how energy balance is regulated. This may lead to better treatment and prevention strategies.
The dynamic responses of energy metabolism under different stimuli are not well understood.
Leitner BP, Huang S, Brychta RJ, Duckworth CJ, Baskin AS, McGehee S, Tal I, Dieckmann W, Gupta G, Kolodny GM, Pacak K, Herscovitch P, Cypess AM, Chen KY. Mapping of human brown adipose tissue in lean and obese young men. Proc Natl Acad Sci U S A. 2017;114(32):8649-8654.
Chen KY, Brychta RJ, Linderman JD, Smith S, Courville A, Dieckmann W, Herscovitch P, Millo CM, Remaley A, Lee P, Celi FS. Brown fat activation mediates cold-induced thermogenesis in adult humans in response to a mild decrease in ambient temperature. J Clin Endocrinol Metab. 2013;98(7):E1218-23.
Lee P, Smith S, Linderman J, Courville AB, Brychta RJ, Dieckmann W, Werner CD, Chen KY, Celi FS. Temperature-acclimated brown adipose tissue modulates insulin sensitivity in humans. Diabetes. 2014;63(11):3686-98.
Chen KY, Cypess AM, Laughlin MR, Haft CR, Hu HH, Bredella MA, Enerbäck S, Kinahan PE, Lichtenbelt Wv, Lin FI, Sunderland JJ, Virtanen KA, Wahl RL. Brown Adipose Reporting Criteria in Imaging STudies (BARCIST 1.0): Recommendations for Standardized FDG-PET/CT Experiments in Humans. Cell Metab. 2016;24(2):210-22.
Chen KY, Muniyappa R, Abel BS, Mullins KP, Staker P, Brychta RJ, Zhao X, Ring M, Psota TL, Cone RD, Panaro BL, Gottesdiener KM, Van der Ploeg LH, Reitman ML, Skarulis MC. RM-493, a melanocortin-4 receptor (MC4R) agonist, increases resting energy expenditure in obese individuals. J Clin Endocrinol Metab. 2015;100(4):1639-45.