Hypocaloric diet and physical activity improved insulin sensitivity and inflammation obese



Hypocaloric diet and increased physical activity improved insulin sensitivity and reduced low-grade inflammation in severely obese subjects.

According to a study from Denmark, "Obesity is associated with low-grade inflammation, insulin resistance, type 2 diabetes, and cardiovascular disease. This study investigated the effect of a 15-wk lifestyle intervention (hypocaloric diet and daily exercise) on inflammatory markers in plasma, adipose tissue (AT), and skeletal muscle (SM) in 27 severely obese subjects (mean body mass index: 45.8 kg/m2)."

J.M. Bruun and colleagues working with Aarhus University Hospital explained, "Plasma samples, subcutaneous abdominal AT biopsies, and vastus lateralis SM biopsies were obtained before and after the intervention and analyzed by ELISA and RT-PCR."

They found, "The intervention reduced body weight (p<0.001) and increased insulin sensitivity (homeostasis model assessment; p<0.05). Plasma adiponectin (p<0.001) increased, and C-reactive protein (p<0.05), IL-6 (p<0.01), IL-8 (p<0.05), and monocyte chemoattractant protein-1 (p<0.01) decreased. AT inflammation was reduced, determined from an increased mRNA expression of adiponectin (p<0.001) and a decreased expression of macrophage-specific markers (CD14, CD68), IL-6, IL-8, and tumor necrosis factor-alpha (p<0.01).

"After adjusting for macrophage infiltration in AT, only IL-6 mRNA was decreased (p<0.05). Only very low levels of inflammatory markers were found in SM. The intervention had no effect on adiponectin receptor 1 and 2 mRNA in AT or SM."

The researchers concluded, "Thus hypocaloric diet and increased physical activity improved insulin sensitivity and reduced low-grade inflammation. Markers of inflammation were particularly reduced in AT, whereas SM does not contribute to this attenuation of whole body inflammation."

Bruun and colleagues published the results of their research in American Journal of Physiology - Endocrinology and Metabolism (Diet and exercise reduce low-grade inflammation and macrophage infiltration in adipose tissue but not in skeletal muscle in severely obese subjects. Am J Physiol Endocrinol Metab, 2006;290(5):E961-E967).

For additional information, contact J.M. Bruun, Aarhus University Hospital, Dept. Endocrinol & Metab C, Aarhus Sygehus, DK-8000 Aarhus C, Denmark.

The publisher of the American Journal of Physiology - Endocrinology and Metabolism can be contacted at: American Physiological Society, 9650 Rockville Pike, Bethesda, MD 20814, USA.

Keywords: Aarhus C, Denmark, Adipokines, Adiponectin, Adipose Tissue, Angiology, Cardiology, Cardiovascular, Cardiovascular Disease, Diabetes, Diet And Nutrition, Endocrinology, Exercise, Gastroenterology, Insulin, Insulin Resistance, Macrophages, Metabolism, Obesity, Physical Fitness, Type 2 Diabetes, Vascular Disease, Weight Loss. This article was prepared by Obesity & Diabetes Week editors from staff and other reports.