Curcumin ameliorates skeletal muscle atrophy in type I diabetic mice via inhibiting the protein ubiquitination.
Exp Physiol. 2015 May 22. Epub 2015 May 22. PMID: 25998196
Skeletal muscle atrophy develops in patients with diabetes mellitus (DM), especially in type 1 DM, which is associated with chronic inflammation. Curcumin, the active ingredient of turmeric, has various biological actions including anti-inflammatory and anti-oxidative properties. We thus hypothesized that curcumin could ameliorate skeletal muscle atrophy in streptozotocin (STZ)-induced type 1 DM mice. C57BL/6 J mice were injected intraperitoneally with 200 mg/kg of STZ (DM) or vehicle (Control). Each group of mice was randomly divided into 2 groups of 10 mice each and fed a diet with or without curcumin (1500 mg/kg/day) for 2 weeks. There were significant decreases in body weight, skeletal muscle weight, and cellular cross-sectional area of the skeletal muscle in DM mice compared to Controls and they were significantly attenuated in DM+Curcumin without affecting plasma glucose and insulin levels. Ubiquitination of protein was increased in skeletal muscle from DM, and decreased in DM+Curcumin. Gene expressions of muscle-specific ubiquitin E3 ligase Atrogin-1/MAFbx and MuRF1 were increased in DM and inhibited in DM+Curcumin. Moreover, NFκB activation, levels of inflammatory cytokines TNF-α and IL-1β, and oxidative stress were increased in the skeletal muscle from DM and inhibited in DM+Curcumin. Curcumin ameliorated skeletal muscle atrophy in DM mice by inhibiting protein ubiquitination, inflammatory cytokines and oxidative stress. Curcumin may be beneficial for the treatment of muscle atrophy in type 1 DM. This article is protected by copyright. All rights reserved.