Sunphenon Epigallocatechin-Gallate (EGCg) in Duchenne Muscular Dystrophy

Duchenne muscular dystrophy (DMD) is the most frequent neuromuscular condition to occur in childhood and youth. The course of the disease is progressive, and life expectancy is severely curtailed by the participation of the respiratory muscles and/or by progressive cardiomyopathy.

DMD derives from mutations in the DMD gene which leads to a loss of the protein dystrophin. Secondary inflammatory/immunological reactions contribute to the progressive course of the disease (1,2).

No curative therapy yet exists. Administration of steroids is the only established medical treatment. Symptomatic measures are also available, such as orthopaedic operations, the treatment of cardiomyopathy or, in advanced stages, home mechanical ventilation.

In studies involving experiments on cells and animals, Epigallocatechin-Gallate (EGCG, the major polyphenol in green tea) has shown a neuroprotective effect. The neuroprotective mechanism of action is probably based on several factors, including EGCG's modulation of several signal transduction pathways, its influence on the expression of genes regulating cell survival or programmed cell death, as well as its modulation of mitochondrial function.

The mdx mouse is the best-investigated animal model of a dystrophin-negative muscular dystrophy. Administration of EGCG in the mdx mouse led to both a reduction in the proportion of fibre necroses as well as to a less pronounced proliferation of connective tissue in the muscle (3,4), and also to an improvement in clinical symptoms (5,6).