L-glutamine Supplementations Enhance Liver Glutamine-Glutathione Axis and Heat Shock Factor-1 Expression in Endurance-Exercise Trained Rats

Autor(es)

Petry, Eder Ricardo ^[1] ; Cruzat, Vinicius Fernandes ^{[1, 2]} ; Heck, Thiago Gomes ^[3] ; Homem de Bittencourt, Jr., Paulo Ivo ^[4] ; Tirapegui, Julio ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Fac Pharmaceut Sci, Dept Food Sci & Expt Nutr, Sao Paulo - Brazil

^[2] Curtin Univ, Biosci Res Precinct, CHIRI, Sch Biomed Sci, Perth, WA 6845 - Australia

^[3] Univ Northwest Rio Grande Sul State, Ijui, RS - Brazil

^[4] Univ Fed Rio Grande do Sul, Inst Basic Hlth Sci, Dept Physiol, Porto Alegre, RS - Brazil

• Tipo de documento: Artigo Científico
• Fonte: INTERNATIONAL JOURNAL OF SPORT NUTRITION AND EXERCISE METABOLISM; v. 25, n. 2, p. 188-197, APR 2015.
• Citações Web of Science: 12

Resumo

Liver L-glutamine is an important vehicle for the transport of ammonia and intermediary metabolism of amino acids between tissues, particularly under catabolic situations, such as high-intensity exercise. Hence, the aim of this study was to investigate the effects of oral supplementations with L-glutamine in its free or dipeptide forms (with L-alanine) on liver glutamine-glutathione (GSH) axis, and 70 kDa heat shock proteins (HSP70)/heat shock transcription factor 1 (HSF1) expressions. Adult male Wistar rats were 8-week trained (60 min/day, 5 days/week) on a treadmill. During the last 21 days, the animals were daily supplemented with 1 g of L-glutamine/kg body weight per day in either 1-alanyl-L-glutamine dipeptide (DIP) form or a solution containing L-glutamine and 1-alanine in their free forms (GLN+ALA) or water (controls). Exercise training increased cytosolic and nuclear HSF1 and HSP70 expression, as compared with sedentary animals. However, both DIP and GLN+ALA supplements enhanced HSF1 expression (in both cytosolic and nuclear fractions) in relation to exercised controls. Interestingly, HSF1 rises were not followed by enhanced HSP70 expression. DIP and GLN+ALA supplements increased plasma glutamine concentrations (by 62% and 59%, respectively) and glutamine to glutamate plasma ratio in relation to trained controls. This was in parallel with a decrease in plasma ammonium levels. Supplementations increased liver GSH (by 90%), attenuating the glutathione disulfide (GSSG) to GSH ratio, suggesting a redox state protection. In conclusion, oral administration with DIP and GLN+ALA supplements in endurance-trained rats improve liver glutamine-GSH axis and modulate HSF1 pathway. (AU)

• Processo FAPESP: 07/58222-8 - Efeito da suplementação com L-alanil-L-glutamina sobre parâmetros de lesão muscular, sistema antioxidante e expressão gênica de HSP-72 e HSF-1 em ratos submetidos a treinamento aeróbio intenso
• Beneficiário: Julio Orlando Tirapegui Toledo
• Modalidade de apoio: Auxílio à Pesquisa - Regular