[Protective effect of LR-90 on articular cartilage in rabbit model of osteoarthritis].

OBJECTIVE

To investigate the protective effect of LR-90 on articular cartilage in rabbit model of osteoarthritis.

METHODS

The cultured rabbits chondrocytes were assigned to be treated with IL-1β (10ng/ml) or IL-1β (10ng/ml)+LR-90 (50 mg/L). The mRNA expression of MMP-13, ADAMTS-5, aggrecan and collagen II in chondrocytes were assessed by real-time quantitative reverse transcription polymerase chain reaction (RT-PCR). Twenty male New Zealand white rabbits underwent bilateral anterior cruciate ligament transection (ACLT) to establish a animal model of osteoarthritis. Four weeks after model established, on the basis of randomization one knee of each rabbit was treated with 50 mg/L LR-90 in normal saline (NS) (experimental group) and the other knee was treated with same volume of NS (control group), 1/week × 5. Nine weeks after ACLT all rabbits were sacrificed and the knee joints were evaluated by gross morphology and histology. The mRNA expression of IL-1β, MMP-13, ADAMTS-5, aggrecan and collagen Ⅱ in articular cartilage was analyzed by RT-PCR.

RESULTS

Gross morphology and Mankin histological evaluation showed that the extent and grade of cartilage damage in the experimental group were less severe than those in the control group.Compared to IL-1β group, LR-90 treatment suppressed the mRNA expression of MMP-13 and ADAMTS-5, and enhanced aggrecan and collagen Ⅱ mRNA expression. Consistent with the in vitro results, the intraarticular LR-90 administration suppressed the mRNA expression of IL-1β,MMP-13 and ADAMTS-5 (all P<0.01), while enhanced mRNA expression of aggrecan and collagen Ⅱ in cartilage (all P<0.01).

CONCLUSION

LR-90 protects against cartilage degradation and inhibits the progression of osteoarthritis in rabbit mode1 of osteoarthritis, which is associated with the suppressing IL-1β, MMP-13, ADAMTS-5 and promoting aggrecan and collagen Ⅱ mRNA expression in cartilage.