Martin E. Young, D.Phil.
Assistant Professor of Pediatrics, Baylor College of Medicine
Prior Appointment: Assistant Professor, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center, Houston, TX
E-mail: meyoung@bcm.edu
Research Interests
Research in my laboratory is focused on identifying the role(s) of the circadian clock in both cardiac and skeletal muscle. Circadian clocks are intrinsically maintained molecular mechanisms that condition the cell to changes in its environment. These circadian clocks therefore confer a selective advantage by providing a mechanism for anticipation of change. We have recently characterized fully the circadian clock within both mammalian heart and skeletal muscle. The broad objective of my laboratory is therefore to test the hypothesis that the circadian clock within these muscle types synchronizes responsiveness of cardiac and skeletal muscle to diurnal variations in their environment. Impairment of this molecular mechanism would therefore result in an inability of these muscles to respond appropriately to the onset of such environmental influences (i.e. maladaptation). The primary humoral factors currently under investigation are nutrients, such as glucose and fatty acids. In the latter case, cardiac and skeletal muscle exhibit dramatic diurnal variations in their responsiveness to fatty acids. Failure to respond adequately to increased fatty acid availability will result in accumulation of intramyocellular fatty acid derivatives. The latter may play a significant role in the pathogenesis of insulin resistance, type II diabetes mellitus, and/or cardiomyopathy. To address this line of reasoning, we have recently generated two novel genetically manipulated mouse models in which the circadian clock is specifically impaired within cardiomyocytes or skeletal myocytes.
Representative Publications
Durgan DJ, Moore MWS, Ha NP, Egbejimi O, Fields A, Mbawuike U, Egbejimi A, Shaw CA, Bray MS, Nannegari V, Hickson-Bick DL, Heird WC, Dyck JRB, Chandler MP, Young ME (2007) Circadian rhythms in oleate-induced depression of myocardial contractile function and efficiency. American Journal of Physiology Heart and Circulatory Physiology Epub ahead of print.
Young ME, Bray MS (2007) Potential role for peripheral circadian clock dyssynchrony in the pathogenesis of cardiovascular dysfunction. Sleep Med Epub ahead of print.
Bray MS, Young ME (2007) Circadian Rhythms in the Development of Obesity: Potential Role for the Circadian Clock within the Adipocyte. Obesity Reviews 8: 169-181.
Durgan DJ, Trexler N, Egbejimi O, Bray MS, Hardin PE, Chandler M, Chow CW, Young ME (2006) The Circadian Clock Within the Cardiomyocyte is Essential for Responsiveness of the Heart to Fatty Acids. J. Biol. Chem. 281; 24254-24269.
Young ME (2006) The Circadian Clock Within the Heart: Potential Influence on Myocardial Gene Expression, Metabolism and Function. American Journal of Physiology Heart and Circulatory Physiology 290: H1-H16.
Durgan DJ, Hotze MA, Tomlin TM, Egbejimi O, Graveleau C, Abel ED, Shaw CA, Bray MS, Hardin PE, Young ME (2005) The intrinsic circadian clock within the cardiomyocyte. American Journal of Physiology Heart and Circulatory Physiology 289: H1530-H1541.
Stavinoha MA, RaySpellicy JW, Hart-Sailors ML, Mersmann HJ, Bray MS, Young ME (2004) Diurnal Variations in the Responsiveness of Cardiac and Skeletal Muscle to Fatty Acids. American Journal of Physiology, Endocrinology and Metabolism 287: E878-E887.
Young ME (2003) Circadian Rhythms in Cardiac Gene Expression. Curr Hypertension Reports 5: 445-453.
Young ME, Wilson CR, Razeghi P, Guthrie PH, Taegtmeyer H (2002) Alterations of the circadian clock in the heart by streptozotocin-induced diabetes. J Mol Cell Cardiol 34: 223-231.
Young ME, Razeghi P, Cedars AM, Guthrie PH, Taegtmeyer H (2001) Intrinsic diurnal variations in cardiac metabolism and contractile function. Circ Res 89: 1199-1208.
Young ME, Razeghi P, Taegtmeyer H (2001) Clock genes in the heart: characterization and attenuation with hypertrophy. Circ Res 88: 1142-1150.