Anticatabolic activity of alpha-ketoglutaric acid in growing rats

This study evaluated the anti-catabolic effect of alpha-ketoglutaric acid (AKG) in rats. Thirty Sprague Dowley male rats were divided into 3 groups of 10 animals each and fed ad libitum with protein-free diet (PFD) supplemented with 0, 3, and 6 g/kg feed of AKG for 14 consecutive days. The AKG administration had no effect on the growth performance of rats in the global trial period (0-14 d). After 7 d of excreta collection, the losses of endogenous nitrogen (N), both urinary and total, linearly reduced (P<0.05) following the administration of AKG, ranging from 35.00 mg/d to 28.00 mg/d, and from 45.28 mg/d to 36.36 mg/d, respectively. The villi and microvilli heights were lower when animals received 3 g/kg of AKG respecting to other tested AKG levels. Indeed, enterocytes length linearly increased (P<0.05) as the level of AKG increased in the diet by 25.0% (3 g/kg) and 49.0% (6 g/kg). The AKG levels quadratically influenced (P<0.05) the essential amino acids (EAA) concentrations in the blood, being EAA lower for animals treated with 6 g/kg of AKG (-21.6%) compared to the animals fed the control PFD and the PFD with 3 g/kg of AKG. In conclusion, AKG was effective in reducing catabolism and EAA depletion.