Green tea extract decreases muscle pathology and NF-κB immunostaining in regenerating muscle fibers of mdx mice

SummaryBackground & aimsDuchenne muscular dystrophy is a debilitating genetic disorder characterized by severe muscle wasting and early death in afflicted boys. The primary cause of this disease is mutations in the dystrophin gene resulting in massive muscle degeneration and inflammation. The purpose of this study was to determine if dystrophic muscle pathology and inflammation were decreased by pre-natal and early dietary intervention with green tea extract.MethodsMdx breeder mice and pups were fed diets containing 0.25% or 0.5% green tea extract and compared to untreated mdx and C57BL/6J mice. Serum creatine kinase was assessed as a systemic indicator of muscle damage. Quantitative histopathological and immunohistochemical techniques were used to determine muscle pathology, macrophage infiltration, and NF-κB localization.ResultsEarly treatment of mdx mice with green tea extract significantly decreased serum creatine kinase by ∼85% at age 42 days (P ≤ 0.05). In these mice, the area of normal fiber morphology was increased by as much as ∼32% (P ≤ 0.05). The primary histopathological change was a ∼21% decrease in the area of regenerating fibers (P ≤ 0.05). NF-κB staining in regenerating muscle fibers was also significantly decreased in green tea extract-treated mdx mice when compared to untreated mdx mice (P ≤ 0.05).ConclusionEarly treatment with green tea extract decreases dystrophic muscle pathology potentially by regulating NF-κB activity in regenerating muscle fibers.