A novel natural tracer method to measure complex carbohydrate metabolism.

ABSTRACT: While the triple tracer isotope dilution method has enabled accurate estimation of carbohydrate turnover after a mixed meal, use of the simple carbohydrate glucose as the carbohydrate source limits its translational applicability to everyday meals that typically contain complex carbohydrates. Hence, utilizing the natural enrichment of [13C]polysaccharide in commercially available grains, we devised a novel tracer method to measure postprandial complex carbohydrate turnover and indices of insulin action and ?-cell function and compared the parameters to those obtained after a simple carbohydrate containing mixed meal. We studied healthy volunteers after either rice (n = 8) or sorghum (n = 8) and glucose (n = 16) containing mixed meals and modified the triple tracer technique to calculate carbohydrate turnover. All meals were matched for calories and macronutrient composition. Rates of meal glucose appearance (2,658?±?736 vs. 4,487?±?909 ?M·kg-1·2 h-1), endogenous glucose production (-835?±?283 vs. -1,123?± 323 ?M·kg-1·2 h-1) and glucose disappearance (1,829?±?807 vs. 3,606?±?839 ?M·kg-1·2 h-1) differed (P < 0.01) between complex and simple carbohydrate containing meals, respectively. Interestingly, there were significant increase in indices of insulin sensitivity (32.5?±?3.5 vs. 25.6?±?3.2 10-5 (dl·kg-1·min-2)/pM, P = 0.006) and ?-cell responsivity (disposition index: 1,817?±?234 vs. 1,236?±?159 10-14 (dl·kg-1·min-2)/pM, P < 0.005) with complex than simple carbohydrate meals. We present a novel triple tracer approach to estimate postprandial turnover of complex carbohydrate containing mixed meals. We also report higher insulin sensitivity and ?-cell responsivity with complex than with simple carbohydrates in mixed meals of identical calorie and macronutrient compositions in healthy adults.

SUBMITTER: Basu R 

PROVIDER: S-EPMC6766609 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature