[Experimental osteoarthritis and its course when treated with S-adenosyl-L-methionine]

Degenerative arthropathy was experimentally induced in the right knee of 24 rabbits. The animals were randomly divided in 3 groups of 8 rabbits each. S-Adenosyl-L-Methionine (SAMe) was administered intramuscularly to 2 groups. One group received 30 and 60 mg/kg/day i.m. The remaining group was a control and received only a diluent. After 12 weeks of therapy rabbits were sacrificed and tibial and femoral cartilage specimens of both knees were taken. The latter was stained with hematoxylin -eosine, Masson's trichromic and Safranine 0 stains and was microscopically studied. The thickness and cell density of the lesioned cartilages were significantly greater in both groups treated with SAMe than the group control (p less than 0.001). Statistical differences (p less than 0.05) were found within 60 and 30 mg/kg/day of SAMe. A greater concentration of proteoglycans in the cartilage matrix was found in animals treated were as, a severe reduction was found in controls. The severity of the lesions, based on the histologic-histochemical analysis, was significantly lower in rabbits receiving SAMe (p less than 0.0005). These differences were correlated with the administration of SAMe and the possible mechanisms of action are discussed.