Abstract
This review examines the molecular mechanisms underlying substrate competition between glucose and lipid in starvation and in insulin-resistant states. We demonstrate that lipid-derived substrates are oxidized in preference to glucose by skeletal muscle in vivo during prolonged starvation. An accelerated and exaggerated lipolytic and ketogenic response to starvation in late pregnancy is associated with more rapid suppression of glucose oxidation by the maternal skeletal-muscle mass. These benign adaptations to changes in lipid availability (which occur secondarily to changes in carbohydrate supply and demand) contrast with the well-documented detrimental effects to health of an inappropriately high supply of dietary lipid. We present results that indicate that the prolonged consumption of a diet high in saturated fat is associated with a stable enhancement of pyruvate dehydrogenase (PDH) kinase activity at least in two oxidative tissues--liver and heart. This long-term enhancement of PDH kinase activity is concomitant with the development of whole-body insulin resistance and adds a new dimension to the potential role of dietary composition in the pathogenesis of insulin resistance.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
