Growth Hormone Replacement Therapy Prevents Sarcopenia by a Dual Mechanism: Improvement of Protein Balance and of Antioxidant Defenses

Abstract

The aim of our study was to elucidate the role of growth hormone (GH) replacement therapy in three of the main mechanisms involved in sarcopenia: alterations in mitochondrial biogenesis, increase in oxidative stress, and alterations in protein balance. We used young and old Wistar rats that received either placebo or low doses of GH to reach normal insulin-like growth factor-1 values observed in the young group. We found an increase in lean body mass and plasma and hepatic insulin-like growth factor-1 levels in the old animals treated with GH. We also found a lowering of age-associated oxidative damage and an induction of antioxidant enzymes in the skeletal muscle of the treated animals. GH replacement therapy resulted in an increase in the skeletal muscle protein synthesis and mitochondrial biogenesis pathways. This was paralleled by a lowering of inhibitory factors in skeletal muscle regeneration and in protein degradation. GH replacement therapy prevents sarcopenia by acting as a double-edged sword, antioxidant and hypertrophic.

Effect of growth hormone replacement therapy on plasma diacron-reactive oxygen metabolites and endothelial function in Japanese patients: The GREAT clinical study

“…GH replacement therapy is known to act as an antioxidant because it upregulates the expression of important intracellular antioxidant enzymes, such as catalase, glutathione peroxidase, and glucose-6-phosphate dehydrogenase [28]. It has been shown that IGF-1 reduces oxidative Correlation of d-ROMs with RHI in GHD stress and atherosclerosis.…”

The pathogenetic bases of sarcopenia

“…Additionally, the levels of growth hormone (GH) and their relevant regulators (Insulinlike Growth Factor-IGF family) are usually lower in the elderly subjects, and these situation could further explain skeletal muscle mass wasting. In a recent in vivo study, Briosche et al (45) proved that GH supplementation in old mice determined an increase in lean body mass, with an elevated synthesis rate of skeletal muscle protein and mitochondrial biogenesis pathways. Moreover, they registered a lowering of age-associated oxidative damage, an increase of plasma and hepatic IGF-1 levels, and an induction of antioxidant enzymes in the skeletal muscle of the treated animals.…”

Effect of beta-hydroxy-beta-methylbutyrate supplementation on muscle loss in older adults: A systematic review and meta-analysis

“…Multiple strategies have been proposed to reduce muscle loss, including exercise training (Montero-Fernandez & Serra-Rexach, 2013), nutritional supplements (Karelis, Messier, Suppere, Briand, & Rabasa-Lhoret, 2015;Malafarina, Uriz-Otano, Iniesta, & GilGuerrero, 2013), and hormone replacement (Brioche et al, 2013). Among these, nutritional supplementation is considered an efficient and a safe method.…”