The effect of DDB on dystrophic hamsters: an in vivo and in vitro study.

Dimethyl-4, 4'-dimethoxy-5, 6, 5'-6'-dimethylenedioxybiphenyl-2, 2'-dicarboxylate (DDB) is a synthetic analogue of Schizandrin C, an active compound isolated from a Chinese herb, Fructus schizandrae. We administered this compound to dystrophic hamsters in vivo for 31 days. This led to a 61% reduction of the calcium content, an 86% reduction of the area of calcium deposits, and a 52% reduction of the area of necrosis of cardiac muscle. However, skeletal muscle necrosis was not significantly improved. No clear change in plasma creatine kinase (CK) was observed. In an in vitro incubation study, the rate of CK release and tetanus tension of the extensor digitorum longus muscle of dystrophic hamsters were not substantially changed by the addition of DDB. This study suggests that DDB has some effect on cardiac necrosis, and that it might be useful for treatment of the cardiac involvement in patients with muscular dystrophy or other conditions with accompaning Ca accumulation.