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Updated: Jun 19, 2025

Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures
Published on: November 11, 2016
Hormonal basis of seasonal metabolic changes in mammalian species
1Department for Experimental Physiology and Pharmacology, Almazov National Medical Research Centre, St. Petersburg, Russia.
Abstract:
Seasonal changes in external conditions (photoperiod, meteorological conditions, diet) cause adaptive changes in both energy and substrate metabolism in the animals of mammalian species. In summer, long days and a rich diet contribute to relative elevation in the levels of thyroid hormones (TH), but warmer weather lowers their levels. In winter, short days and a poor diet inhibit TH synthesis, but low temperatures increase their secretion. In addition, the results of our meta-analyses revealed a significant role of atmospheric pressure in circannual fluctuations of metabolic parameters in humans. The changes in photoperiod are generally viewed as a major factor contributing to seasonal rhythm regulation However, numerous data show that season-dependent metabolic changes in mammals could be also accounted for by meteorological factors and diet.
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