Nutrition and Obesity Prevention 

Biography

Biography: Ajmila Islam

Abstract

Dietary interventions that reduce accumulation of body fat are of great interest. Consumption of viscous dietary fibres causes well-known positive metabolic effects, such as reductions in the postprandial glucose and insulin concentrations. However, their effect on body composition and fuel utilization has not been previously studied. To examine this, rats were fed a viscous non-fermentable dietary fibre, Hydroxypropyl Methylcellulose (HPMC), for 6 weeks. Body composition was measured by Dual-energy X-ray Absorptiometry (DXA) and fat pad weight. Plasma adipokines, AMP kinase activation and enzyme and mRNA analysis of key regulators of energetics in liver and soleus muscle were measured. The HPMC diet significantly lowered per cent body fat mass and increased per cent lean body mass, compared to a cellulose-containing diet (no viscosity). Fasting leptin was reduced by 42% and resistin 28% in the HPMC group compared to the cellulose group. Rats fed HPMC had greater activation of AMP kinase in liver and muscle and lower Phosphoenolpyruvate Carboxykinase (PEPCK) expression in liver. mRNA expression in skeletal muscle was significantly increased for Carnitine Palmitoyltransferase 1B (CPT-1B), PPARγ co-activator 1α, PPARδ and Uncoupling Protein 3 (UCP3) were Citrate Synthase (CS) activity, in the HPMC group relative to the cellulose group. These results indicated that viscous dietary fibre preserves lean body mass and reduces adiposity, possibly by increasing mitochondrial biogenesis and fatty acid oxidation in skeletal muscle and thus represents a metabolic effect of viscous fibre not previously described. Thus, the viscous dietary fibre may be a useful dietary component to assist in the reduction of body fat.