[Homeostatic non-shivering thermogenesis in man: facts and speculations]

Abstract

In this review it is considered up-to date researches of different forms of non-shivering thermogenesis that related to thermoregulatory and substrate homeostasis. Term "homeostatic non-shivering thermogenesis (HNST)" is proposed for explanation of facultative heat production stimulated by cold exposure, food intake and accumulation of lactate during intensive muscle load. There are common and different features of physiological activity displayed in three HNST types. Existence of these common points gets a probability to propose general physiological mechanisms of HNST realization. Between other candidates for HNST location brown adipose tissue (BAT) has real unquestionable advantage for this specific function. There is close relationship between thermogenic function in cold environment and diet-induced thermogenesis that allows to link two HNST types and BAT activity together. Here we present data indirectly confirming BAT functioning in processes of homeostatic normalization not due to cold acclimation or food intake. Also we give consideration to new data about BAT functional activity, its topographic body location, mechanisms of uncoupled respiration in different tissues in adult humans and methods of BAT diagnostics which include molecular marker using. We adduce a number of facts confirming our suggestion about BAT activity can be related to homeostatic normalization after physical load. At last, we bring forward experimental research program for examination of our hypothesis about BAT universal homeostatic function in humans.