Interaction of Ingested Leucine with Glycine on Insulin and Glucose Concentrations. (10th July 2014)

• Record Type: Journal Article
• Authors: Iverson, Jennifer F.; Gannon, Mary C.; Nuttall, Frank Q.
• Other Names: Gietzen Dorothy Academic Editor.
• Is Part Of: Journal of amino acids. Volume 2014(2014)
• Publication Date: 2014-07-10
• Subjects: Amino acids -- Periodicals; Amino Acids; Amino acids; Electronic journals; Periodical; Periodicals; 612.015756
• DOI: 10.1155/2014/521941
• Languages: English
• ISSNs: 2090-0404

Abstract

Abstract : The majority of individual amino acids increase insulin and attenuate the plasma glucose response when ingested with glucose. Objective. To determine whether ingestion of two amino acids simultaneously, with glucose, would result in an additive effect. Leucine (Leu) and glycine (Gly) were chosen because they were two of the most potent glucose-lowering amino acids when given individually. Materials and Methods. Nine subjects received test items on four separate days. The first was a water control, then 25 g glucose, or Leu + Gly (1 mmol/kg fat-free mass each) ±25 g glucose, in random order. Glucose, insulin, and glucagon were measured frequently for 2.5 hours. Net areas were calculated. Results. The glucose area response decreased by 66%. The insulin area response increased by 24% after ingestion of Leu + Gly + glucose compared to ingestion of glucose alone. The decrease in glucose response was not additive; the increase in insulin response was far less than additive when compared to previously published individual amino acid results. The glucagon concentration remained unchanged. Conclusion. There is an interaction between Leu and Gly that results in a markedly attenuated glucose response. This occurred with a very modest increase in insulin response. Changes in glucagon response could not explain the results. The mechanism is unknown.