Thyroid hormones are important regulators of mitochondrial metabolism. Due to their complex mechanism of action, the timescale of different responses varies from minutes to days. In this work, we studied selective T3 induction of the inner mitochondrial membrane enzyme-glycerophosphate dehydrogenase (mGPDH) in liver of euthyroid rats. We correlated the kinetics of the T3 level in blood, the mRNA level in liver, the activity and amount of mGPDH in liver mitochondria after a single dose of T3. The T3 level reached maximum after 1 h (80 nmol/l) and subsequently rapidly decreased. mGPDH mRNA increased also relatively fast, reaching a maximum after 12 h and fell to the control level after 72 h. An increase of mGPDH activity could be already found after 6 h and reached a maximum after 24 h in accordance with the increase in mGPDH content (2.4-fold vs. 2.7-fold induction). After 72 h, the mGPDH activity showed a significant 30% decrease. When the rats received three subsequent doses of T3, the increase of mGPDH activity was 2-fold higher than after a single T3 dose. The results demonstrate that mGPDH displays rapid induction as well as decay upon disappearance of a hormonal stimulus, indicating a rather short half-life of this inner mitochondrial membrane enzyme.

Department of Bioenergetics Institute of Physiology Academy of Sciences of the Czech Republic Vídenská 1083 142 20 Prague 4 Czech Republic

Citace poskytuje Crossref.org

Czech Footprints in the Bioenergetics Research

Role of Mitochondrial Glycerol-3-Phosphate Dehydrogenase in Metabolic Adaptations of Prostate Cancer

Pleiotropic Effects of Biguanides on Mitochondrial Reactive Oxygen Species Production

Ubiquinone-binding site mutagenesis reveals the role of mitochondrial complex II in cell death initiation