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Physiol. Res. 55: 123-131, 2006
MINIREVIEW
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Steroids and Thermogenesis
R. HAMPL, L. STÁRKA, L. JANSKÝ1
Institute of Endocrinology, Prague and 1Faculty of Biology, University of
South Bohemia, Ceské Budejovice, Czech Republic
Received January 31, 2005
Accepted March 21, 2005
On-line available
Summary
Apart from thyroid hormones, as the main hormonal regulators of obligatory
thermogenesis, and catecholamines, as major hormonal regulators of
facultative thermogenesis, production of heat in homeotherms can also be
influenced by steroids. Generally, hormones can influence heat production
by regulating the activity of various enzymes of oxidative metabolism, by
modulating membrane protein carriers and other membrane or nuclear protein
factors. Proton carriers in the inner mitochondrial membrane, known as
uncoupling proteins, play the key role in heat dissipation to the detriment
of the formation of energy-rich phosphates. In this minireview we have
focused on the effects of steroids and thyroid hormones on heat production
in brown adipose tissues and in skeletal muscles, with particular respect
to their effect on uncoupling protein expression. Apart from hormonal
steroids, dehydroepiandrosterone, an important precursor in the metabolic
pathway leading to hormonal steroids which possess many, mostly beneficial
effects on human health, modulates metabolic pathways which may lead to
increased heat production. Recent studies demonstrate that
7-oxo-dehydroepiandrosterone, one of its 7-oxygenated metabolites, is even
more effective than dehydroepiandrosterone. Recent findings of various
actions of these steroids support the view that they may also participate
in modulating thermogenic effects.
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