Amino Acid Mixture Identical to Vespa Larval Saliva Increases both Leptin Secretion and Basal Lipolysis in Rat Adipocytes

Abstract

The effect of vespa amino acid mixture solution (VAAM), a unique amino acid mixture identified in the saliva of the larva of a species of hornet endemic to Japan on adipocyte lipolysis was investigated in order to verify the possible mechanisms underlying the regulatory effect of VAAM on in vivo fat metabolism. VAAM significantly increased basal leptin secretion and lipolysis without an increase in cAMP production. However, VAAM failed to amplify either isoproterenol or dibutylyl cAMP-stimulated lipolysis, which is increased intracellular cAMP productions, accompanied by a significant decrease in leptin secretion. These results suggest that VAAM may enhance basal lipolysis independent of cAMP productions, but is dependant on leptin secretion from adipocytes themselves, at least in part.