Alanyl-glutamine and glutamine plus alanine supplements improve skeletal redox status in trained rats: Involvement of heat shock protein pathways

We hypothesized that oral l-glutamine supplementations could attenuate muscle damage and oxidative stress, mediated by glutathione (GSH) in high-intensity aerobic exercise by increasing the 70-kDa heat shock proteins (HSP70) and heat shock factor 1 (HSF1). Adult male Wistar rats were 8-week trained (60-min/day, 5days/week) on a treadmill. During the last 21days, the animals were supplemented with either l-alanyl-l-glutamine dipeptide (1.5g/kg, DIP) or a solution containing the amino acids l-glutamine (1g/kg) and l-alanine (0.67g/kg) in their free form (GLN+ALA) or water (controls). Plasma from both DIP- and GLN+ALA-treated animals showed higher l-glutamine concentrations and reduced ammonium, malondialdehyde, myoglobin and creatine kinase activity. In the soleus and gastrocnemius muscle of both supplemented groups, l-glutamine and GSH contents were increased and GSH disulfide (GSSG) to GSH ratio was attenuated (p