Neonatal vitamin A injection promotes cattle muscle growth and increases oxidative muscle fibers

• Published in: Journal of animal science and biotechnology 2018-11, Vol.9 (1), p.82-82, Article 82
• Main Authors: Wang, Bo, Nie, Wei, Fu, Xing, de Avila, Jeanene M, Ma, Yannan, Zhu, Mei-Jun, Maquivar, Martin, Parish, Steven M, Busboom, Jan R, Nelson, Mark L, Du, Min
• Format: Article
• Language: English
• Subjects: Acids; Age; Beef; Beef cattle; Biopsy; Bovidae; Calves; Cattle; Cell density; Cell differentiation; Cells (biology); Dietary fiber; Differentiation (biology); Fibers; Gene expression; Glycerol; Injection; Leukocytes (mononuclear); Metabolism; Metabolites; Morphogenesis; Muscle Fiber type; Muscle growth; Muscles; Musculoskeletal system; MyoD protein; Myogenesis; Myotubes; Neonates; Palmitic acid; PAX7; Regulators; Retinoic acid; Satellite cells; Skeletal muscle; Stem cells; Vitamin A
• ISSN: 1674-9782; 2049-1891; 2049-1891
• DOI: 10.1186/s40104-018-0296-3

Vitamin A and its metabolite, retinoic acid (RA), are important regulators of cell differentiation and organ morphogenesis. Its impact on beef cattle muscle growth remains undefined. Angus steer calves were administrated with 0 (control) or 150,000 IU vitamin A (retinyl palmitate in glycerol, i.m.) per calf at birth and 1 month of age. At 2 months of age, a biopsy of the muscle was obtained to analyze the immediate effects of vitamin A injection on myogenic capacity of muscle cells. The resulting steers were harvested at 14 months of age. Vitamin A administration increased cattle growth at 2 months. At 2 months of age, Vitamin A increased PAX7 positive satellite cells and the expression of myogenic marker genes including , , and . Muscle derived mononuclear cells were further isolated and induced myogenesis in vitro. More myotubes and a higher degree of myogenesis was observed in vitamin A groups. Consistently, vitamin A increased (LD) muscle fiber size at harvest. In addition, vitamin A increased the ratio of oxidative type I and type IIA fibers and reduced the glycolic type IIX fibers. Furthermore, we found that RA, a key bioactive metabolite of vitamin A, activated promoter, which explains the upregulated expression of in skeletal muscle. Vitamin A administration to neonatal calves enhanced postnatal muscle growth by promoting myogenesis and increasing satellite cell density, accompanied with a shift to oxidative muscle fibers.