Green tea extract decreases muscle necrosis in mdx mice and protects against reactive oxygen species.
BACKGROUND
Duchenne muscular dystrophy is a severe X-linked congenital disorder characterized by lethal muscle wasting caused by the absence of the structural protein dystrophin.


OBJECTIVE
Because generation of reactive oxygen species appears to play an important role in the pathogenesis of this disease, we tested whether antioxidant green tea extract could diminish muscle necrosis in the mdx mouse dystrophy model.


METHODS
A diet supplemented with 0.01% or 0.05% green tea extract was fed to dams and neonates for 4 wk beginning on the day of birth. Muscle necrosis and regeneration were determined in stained cryosections of soleus and elongator digitorum longus muscles. Radical scavenging by green tea extract was determined in differentiated cultured C2C12 cells treated with tert-butylhydroperoxide, with the use of 2',7'-dichlorofluorescin diacetate as a radical detector.


RESULTS
This feeding regimen significantly and dose-dependently reduced necrosis in the fast-twitch muscle elongator digitorum longus but at the doses tested had no effect on the slow-twitch soleus muscle. Green tea extract concentration-dependently decreased oxidative stress induced by tert-butylhydroperoxide treatment of cultured mouse C2C12 myotubes. The lower effective dose tested in mdx mice corresponds to approximately equal to 1.4 L (7 cups) green tea/d in humans.


CONCLUSIONS
Green tea extract may improve muscle health by reducing or delaying necrosis in mdx mice by an antioxidant mechanism.
Buetler
Timo M
TM
Pharmacology Group, School of Pharmacy, University of Lausanne, Switzerland.
Renard
Mathilde
M
Offord
Elizabeth A
EA
Schneider
Heinz
H
Ruegg
Urs T
UT
D000818:Animals; D000975:Antioxidants / Q000627:therapeutic use*; D002478:Cells, Cultured; D004032:Diet; D051379:Mice; D018482:Muscle, Skeletal / Q000187:drug effects / Q000473:pathology*; D020388:Muscular Dystrophy, Duchenne / Q000517:prevention & control*; D009336:Necrosis; D010936:Plant Extracts / Q000627:therapeutic use*; D017382:Reactive Oxygen Species; D013662:Tea
D000975:Antioxidants; D010936:Plant Extracts; D017382:Reactive Oxygen Species; D013662:Tea