Acute lysine supplementation does not improve hepatic or peripheral insulin sensitivity in older, obese individuals (1161.7)

Abstract

Context: Lysine supplementation may have a positive influence on the regulation of glucose metabolism but it has not been evaluated in older individuals.Objective: We evaluated the impact of acute lysine supplementation using three randomized experimental scenarios: 1) oral glucose alone (control), 2) oral glucose and low‐dose lysine (2 g), and oral glucose and high dose lysine (5 g) lysine in 7 older (66±1 years/age), overweight (BMI = 31±2 kg/m2) individuals.Methods: We utilized a dual tracer technique (ie., [1‐13C] glucose oral ingestion and [6,6‐2H2] glucose infusion) during an oral glucose tolerance test (OGTT) to examine differences in hepatic and peripheral insulin sensitivity under all three scenarios.Results: Plasma glucose and insulin data were not different between the control, 2 g lysine and 5 g of lysine trials. The results of the Matsuda index were also not different between the three trials. As an index of hepatic insulin sensitivity, there were no significant differences in the endogenous glucose rate of appearance (glucose Ra) for control, 2 g lysine and 5 g lysine (1.2±0.1, 1.1±0.1, 1.3±0.1 mg•kg‐1•min‐1), respectively. With respect to peripheral insulin sensitivity, there were no significant differences in the glucose rate of disappearance (glucose Rd) for control, 2 g lysine and 5 g lysine (4.2±0.2, 4.3±0.2, and 4.5±0.4 mg•kg‐1•min‐1), respectively.Conclusions: Previous studies in younger participants have suggested that lysine may have a beneficial effect on glucose metabolism. Unfortunately, acute lysine supplementation in the older population does not facilitate beneficial changes in glucose Ra or glucose Rd.Grant Funding Source: NIH grants 1P30AG028718‐01A2; UL1TR000039 and KL2TR000063