Effects of a Vespa amino acid mixture identical to hornet larval saliva on the blood biochemical indices of running rats

Abstract

A unique amino acid mixture identical in composition to that of larval saliva of the hornet, referred to as a Vespa amino acid mixture (VAAM) was prepared; the effect of VAAM on the blood biochemical indices and plasma amino acid composition of running rats was studied. Thirty min before running exercise, VAAM, a reference amino acid mixture with a composition identical to that of bovine casein (casein amino acid mixture, CAAM), or distilled water was orally administered to the rats. The blood glucose value in the animals given VAAM did not fall after 45 min of running, the value being significantly higher than that in the rats given CAAM or water (P<0.05). There was no significant change in the blood lactate value for those rats given VAAM, whereas the value in the rats given CAAM or water had significantly increased after 45 min of running (P<0.05). The plasma NEFA value for the VAAM group was significantly higher than that for the CAAM group after 45 min of running (P<0.05). Thirty min after the administration of VAAM or CAAM, the increase in the plasma concentration of amino acids reflected the composition of the amino acid mixture. However, after 45 min of running, the concentration of total plasma amino acid in rats given VAAM was maintained at a higher level than that in the rats given CAAM (3.57±0.30 vs 2.96±0.14 μM/l); the plasma concentrations of Gly, Thr, Tyr and Pro in the rats given VAAM were significantly higher than those in the rats given CAAM. These findings suggest that some amino acids in ingested VAAM were used for gluconeogenesis or as energy sources for muscles during exercise. In addition, a promotive effect of VAAM on the utilization of body fat as an energy source could have been involved in the changes of blood biochemical indices.