To access the protective effects of glucosamine hydrochloride capsules (OTL) on articular cartilage in osteoarthritis of rabbit.
Thirty-six New Zealand white rabbits were divided randomly into three groups (n=12): sham group (group A), anterior cruciate ligament transection (ACLT)/normal saline group (group B), and ACLT/OTL group (group C). Rabbits in groups B, C received ACLT on the right knee. Rabbits in group A were not given ACLT as control. Group C received a daily administration of OTL at a dose of 150 mg/kg of body weight for 12 weeks; in contrast, group B received normal saline at the same dose. All rabbits were sacrificed after 12 weeks. The right femoral condyle were removed and observed at pathologic changes with HE staining and graded by Mankin's scale, the expression level of transforming growth factor beta 1 (TGF-beta 1) and interleukin 1 beta (IL-1 beta) were detected by immunohistochemical staining.
All rabbits survived at the end of experiment and incision healed well. The gross observation showed that joint synovia increased and articular surface was smooth and integrity in group A; that ulcer was observed on the articular surface of group B; and that articular surface was smooth and integrity in group C. There were significant differences in articular cartilage scores between 3 groups (P < 0.05). The histological observation showed that the articular cartilage had normal structure and the cells arranged regularly in group A; that the articular cartilage became thin and the cells arranged irregularly in group B; and that the cells arranged with a clear layer and had regular shape in group C. The Mankin scores were 1.04 +/- 0.13, 7.97 +/- 0.12, and 2.81 +/- 0.36 in groups A, B, and C, respectively; showing significant difference between 3 groups (P < 0.05). The result of immunohistochemistry showed that the expressions of TGF-beta 1 were 50.62 +/- 1.51, 24.81 +/- 1.28, and 41.57 +/- 1.69 and the expressions of IL-1 beta were 13.12 +/- 1.21, 62.53 +/- 2.37, and 30.67 +/- 1.28; showing significant differences between 3 groups (P < 0.05).
A daily administration of OTL at a dose of 150 mg/kg for 12 weeks can partially decrease the expression levels of IL-1 beta and increase the expression levels of TGF-beta 1, which delays the development of osteoarthritis.