MINIREVIEW
Steroids and Thermogenesis
R. HAMPL, L. STÁRKA, L. JANSKÝ1
Institute of Endocrinology, Prague and 1Faculty of
Biology, University of South Bohemia, České Budějovice, 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.
Key words
Steroids • Thyroid hormones • Thermogenesis• Uncoupling proteins
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