FREE-RADICALS, LIPID PEROXIDES AND ANTIOXIDANTS IN BLOOD OF PATIENTS WITH MYOTONIC-DYSTROPHY

We studied the levels of free radicals, lipid peroxides and antioxidan ts, as well as superoxide dismutase (SOD) activity in the blood of six patients with myotonic dystrophy (MyD) (mean age 52.8, SD 5.0 years) and seven controls (mean age 48.8, SD 6.3 years). Electron spin resona nce was used to assess the free radicals by the spin-trapping method u sing 5,5-dimethyl- 1-pyrroline-1-oxide. The levels of C centre radical (P < 0.05) and H radical (P < 0.05) in blood from the six MyD patient s were significantly higher than those in the seven controls. The SOD activities in red blood cells and serum from the six MyD patients show ed no significant difference from those in the seven controls. The ser um lipid peroxide concentration was increased in five of the MyD patie nts and tended to increase further as the disease progressed. The seru m vitamin E level was low in two patients and in the low normal range in three. Serum coenzyme Q(10) was decreased in four patients. The ser um selenium level was decreased in two patients and that of serum albu min was decreased in three. Therefore we conclude that increased level s of free radicals and lipid peroxides and decreased antioxidant level s play an important role in the pathogenesis of MyD.