L-glutamine supplementations enhance liver glutamine-glutathione axis and heat shock factor-1 expression in endurance-exercise trained rats
MetadataShow full item record
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 l-alanyl-L-glutamine dipeptide (DIP) form or a solution containing L-glutamine and l-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.
Showing items related by title, author, creator and subject.
L-glutamine and L-alanine supplementation increase glutamine-glutathione axis and muscle HSP-27 in rats trained using a progressive high-intensity resistance exerciseLeite, J.; Raizel, R.; Hypólito, T.; Dos Santos Rosa, T.; Cruzat, Vinicius; Tirapegui, J. (2016)In this study we investigated the chronic effects of oral L-glutamine and L-alanine supplementation, either in their free or dipeptide form, on glutamine-glutathione (GLN-GSH) axis and cytoprotection mediated by HSP-27 ...
Oral free and dipeptide forms of glutamine supplementation attenuate oxidative stress and inflammation induced by endotoxemiaCruzat, Vinicius; Bittencourt, A.; Scomazzon, S.; Leite, J.; de Bittencourt Jr, P.; Tirapegui, J. (2014)Objective: The aim of the present study was to determine the effects of oral supplementation with L-glutamine plus L-alanine (GLN+ALA), both in the free form and L-alanyl-L-glutamine dipeptide (DIP) in endotoxemic mice. ...
Effects of oral supplementation with glutamine and alanyl-glutamine on glutamine, glutamate, and glutathione status in trained rats and subjected to long-duration exerciseCruzat, Vinicius; Tirapegui, J. (2009)Objective: We investigated the effect of supplementation with the dipeptide L-alanyl-L-glutamine (DIP) and a solution containing L-glutamine and L-alanine, both in the free form, on the plasma and tissue concentrations ...