Effect of dietary mannoheptulose on whole body glucose and energy metabolism in adult neutered male Labrador Retrievers

Abstract

The objective of this study was to determine the effect of dietary mannoheptulose (MH) on glucose and energy metabolism in adult male neutered Labrador Retrievers (N = 6, 5.4 y). This study was designed as a cross‐over with each dog receiving both dietary treatments, control (CON) and MH (200 mg/kg), in random order. Fasting and post‐prandial respiratory quotient (RQ) and energy expenditure (EE) were determined by indirect calorimetry (d 16). Glucose kinetics were assessed during fasting and repeated meal feeding using indirect calorimetry and a primed continuous infusion of U‐13C‐glucose (d 18). A fasting biceps femoris muscle sample was obtained (d 21/22) to determine protein content of phosphorylated and total adenosine monophosphate‐activated protein kinase (AMPK) and acetyl CoA carboxylase (ACC). Diet did not affect plasma glucose, insulin, FFA or glucose turnover during fasting or repeated meal feeding. There were no diet‐related differences in glucose oxidation or energy metabolism in the fed state. However, there were trends for MH to increase RQ (p=0.14) and glucose oxidation (p=0.16) and to lower the ratio of phosphorylated to total AMPK protein content (P=0.08) during fasting. These findings suggest daily MH feeding may affect carbohydrate utilization during fasting.Grant Funding Source: Procter and Gamble Pet Care