Triiodothyronine and leptin repletion in humans similarly reverse weight-loss-induced changes in skeletal muscle
| Autor: | Dympna Gallagher, Rochelle L. Goldsmith, Rudolph L. Leibel, Kenneth M. Baldwin, Michael Rosenbaum, Richard M. Smiley, Fadia Haddad |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
0301 basic medicine
Adult Leptin Male medicine.medical_specialty Physiology Endocrinology Diabetes and Metabolism 030209 endocrinology & metabolism Work efficiency Energy homeostasis 03 medical and health sciences Young Adult 0302 clinical medicine Weight loss Physiology (medical) Internal medicine Weight Loss Medicine Humans Single-Blind Method Obesity Muscle Skeletal Triiodothyronine Cross-Over Studies business.industry Thyroid Skeletal muscle 030104 developmental biology medicine.anatomical_structure Endocrinology Thyroid hormones Female medicine.symptom business Energy Metabolism Research Article |
| Zdroj: | American journal of physiology. Endocrinology and metabolism. 315(5) |
| ISSN: | 1522-1555 |
| Popis: | Subjects maintaining a ≥10% dietary weight loss exhibit decreased circulating concentrations of bioactive thyroid hormones and increased skeletal muscle work efficiency largely due to increased expression of more-efficient myosin heavy chain (MHC) isoforms (MHC I) and significantly mediated by the adipocyte-derived hormone leptin. The primary purpose of this study was to examine the effects of triiodothyronine (T3) repletion on energy homeostasis and skeletal muscle physiology in weight-reduced subjects and to compare these results with the effects of leptin repletion. Nine healthy in-patients with obesity were studied at usual weight (Wtinitial) and following a 10% dietary weight loss while receiving 5 wk of a placebo (Wt−10%placebo) or T3 (Wt−10%T3) in a single-blind crossover design. Primary outcome variables were skeletal muscle work efficiency and vastus lateralis muscle mRNA expression. These results were compared with the effects of leptin repletion in a population of 22 subjects, some of whom participated in a previous study. At Wt−10%placebo, skeletal muscle work efficiency and relative expression of the more-efficient/less-efficient MHC I/MHC II isoforms were significantly increased and the ratio of the less-efficient to the more-efficient sarco(endo)plasmic reticulum Ca2+-ATPase isoforms (SERCA1/SERCA2) was significantly decreased. These changes were largely reversed by T3 repletion to a degree similar to the changes that occurred with leptin repletion. These data support the hypothesis that the effects of leptin on energy expenditure in weight-reduced individuals are largely mediated by T3 and suggest that further study of the possible role of thyroid hormone repletion as adjunctive therapy to help sustain weight loss is needed. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|