Metabolic and functional effects of beta-hydroxy-beta-methylbutyrate (HMB) supplementation in skeletal muscle

Autor(es)

da Justa Pinheiro, Carlos Hermano ^[1] ; Gerlinger-Romero, Frederico ^[1] ; Guimaraes-Ferreira, Lucas ^[1] ; de Souza-Jr, Alcione Lescano ^[2] ; Vitzel, Kaio Fernando ^[2] ; Nachbar, Renato Tadeu ^[2] ; Nunes, Maria Tereza ^[2] ; Curi, Rui ^[2]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Physiol & Biophys, Inst Biomed Sci, BR-05508900 Sao Paulo - Brazil

^[2] de Souza-Jr, Jr., Alcione Lescano, Univ Sao Paulo, Dept Physiol & Biophys, Inst Biomed Sci, BR-05508900 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY; v. 112, n. 7, p. 2531-2537, JUL 2012.
• Citações Web of Science: 38

Resumo

Beta-hydroxy-beta-methylbutyrate (HMB) is a metabolite derived from leucine. The anti-catabolic effect of HMB is well documented but its effect upon skeletal muscle strength and fatigue is still uncertain. In the present study, male Wistar rats were supplemented with HMB (320 mg/kg per day) for 4 weeks. Placebo group received saline solution only. Muscle strength (twitch and tetanic force) and resistance to acute muscle fatigue of the gastrocnemius muscle were evaluated by direct electrical stimulation of the sciatic nerve. The content of ATP and glycogen in red and white portions of gastrocnemius muscle were also evaluated. The effect of HMB on citrate synthase (CS) activity was also investigated. Muscle tetanic force was increased by HMB supplementation. No change was observed in time to peak of contraction and relaxation time. Resistance to acute muscle fatigue during intense contractile activity was also improved after HMB supplementation. Glycogen content was increased in both white (by fivefold) and red (by fourfold) portions of gastrocnemius muscle. HMB supplementation also increased the ATP content in red (by twofold) and white (1.2-fold) portions of gastrocnemius muscle. CS activity was increased by twofold in red portion of gastrocnemius muscle. These results support the proposition that HMB supplementation have marked change in oxidative metabolism improving muscle strength generation and performance during intense contractions. (AU)

• Processo FAPESP: 08/54693-9 - Efeito da terapia com células-tronco musculares e células-tronco mesenquimais na regeneração do músculo esquelético: possível modulação por ácido oléico
• Beneficiário: Carlos Hermano da Justa Pinheiro
• Linha de fomento: Bolsas no Brasil - Doutorado