The effects of dietary β-guanidinopropionic acid on growth and muscle fiber development in juvenile red porgy, Pagrus pagrus

Abstract

β-guandinopropionic acid (β-GPA) has been used in mammalian models to reduce intracellular phosphocreatine (PCr) concentration, which in turn lowers the energetic state of cells. This leads to changes in signaling pathways that attempt to re-establish energetic homeostasis. Changes in those pathways elicit effects similar to those of exercise such as changes in body and muscle growth, metabolism, endurance and health. Generally, exercise effects are beneficial to fish health and aquaculture, but inducing exercise in fishes can be impractical. Therefore, this study evaluated the potential use of supplemental β-GPA to induce exercise-like effects in a rapidly growing juvenile teleost, the red porgy (Pagrus pagrus). We demonstrate for the first time that β-GPA can be transported into teleost muscle fibers and is phosphorylated, and that this perturbs the intracellular energetic state of the cells, although to a lesser degree than typically seen in mammals. β-GPA did not affect whole animal growth, nor did it influence skeletal muscle fiber size or myonuclear recruitment. There was, however, an increase in mitochondrial volume within myofibers in treated fish. GC/MS metabolomic analysis revealed shifts in amino acid composition of the musculature, putatively reflecting increases in connective tissue and decreases in protein synthesis that are associated with β-GPA treatment. These results suggest that β-GPA modestly affects fish muscle in a manner similar to that observed in mammals, and that β-GPA may have application to aquaculture by providing a more practical means of generating some of the beneficial effects of exercise in fishes.

Effects of hydroxyproline supplementation in low fish meal diets on collagen synthesis, myofiber development and muscular texture of juvenile Pacific white shrimp (Litopenaeus vannamei)

“…The taste of muscle is not only influenced by its flavor but also by the characteristics and type of muscle fiber. Hypertrophy of myofiber defined by an augment in the diameter or size of the myofiber and myofiber hyperplasia defined by an augment in the number of myofibers are two processes associated with myofiber growth ( White et al., 2018 ). In general, an increase in myofiber density and a decrease in myofiber diameter are among the reasons that lead to an increase in muscle chewiness, thereby improving muscle quality ( Dunajski, 1980 ; Espe, 2008 ; Johnston et al., 2000 ; Lin et al., 2009 ).…”

Implications of vitamin D for flesh quality of grass carp (Ctenopharyngodon idella): antioxidant ability, nutritional value, sensory quality, and myofiber characteristics

“…Myocyte enhancer factors (MEFs) cooperate with myogenic regulatory factors (MRFs) to activate muscle-related gene expression, playing an important role in all stages of the differentiation process [ 23 ]. Meanwhile, myotube formation increases myofiber diameter and abundance, thus reflecting the importance of maintaining an optimal balance between protein synthesis and degradation [ 24 ]. In rats, vitamin D deficiency depressed growth and protein turnover in skeletal muscle [ 25 ], indicating an important role in myofiber development.…”

Selenium deficiency-induced high concentration of reactive oxygen species restricts hypertrophic growth of skeletal muscle in juvenile zebrafish by suppressing TORC1-mediated protein synthesis

“…These processes are much sensitive to body nutritional state. Increasing evidence suggests that they can be widely influenced by both the quantity and quality of various nutrients, including protein (2,3) , lipid (4,5) , carbohydrates (4,6) , amino acids (7)(8)(9) , amino acid derivatives (10) , nucleotides (11) and vitamins (12,13) , etc. However, limited information is available on the effects of mineral nutrients.…”