Chronic Intermittent Hypobaric Hypoxia Ameliorated Inflammation of Skeletal Muscle via Inhibited NF-kappa B in Rats with Metabolic Syndrome

Abstract

This study was aimed to confirm the hypothesis that Chronic intermittent hypobaric hypoxia (CIHH) could ameliorate inflammation of skeletal muscle in rats with metabolic syndrome (MS). Sprague-Dawley rats (male, 160-180 g) were randomly divided into 4 groups: control group (CON), fructose group (FRUC, 10% fructose in drinking water for 6 weeks), CIHH group (simulated 5,000 m altitude, 6 h per day for 6 weeks), and CIHH plus fructose groups (CIHH-F). Histopathology of skeletal muscle, systolic arterial pressure (SAP), blood biochemical, protein expression of TNFα, MCP-1 and NF-kappa B were measured. The SAP, body weight, and the plasma contents of glucose, insulin, insulin C peptide, triglyceride and total cholesterol were elevated in FRUC rats but not in CIHH-F rats. Meanwhile, the inflammatory response of skeletal muscle was presented in FRUC rats but not in CIHH-F rats, which was demonstrated by the infiltration of circulating mononuclear cells and the up-regulation of TNFα and MCP-1. Finally the protein expression of NF-kappa B in skeletal muscle was correspondingly up-regulated in FRUC rats, but such upregulation was not observed in CIHH-F rats. Our results suggest that CIHH prevents the inflammation of skeletal muscle in rats with MS via inhibiting NF-kappa B signaling. CIHH might be the new strategy for prevention and therapy of MS.