OBJECTIVE: To probe into the cartilage protective effect and molecular mechanism of icariin（ICA） combined with platelet-rich plasma（PRP） on osteoarthritis（OA） in vitro and in vivo. METHODS:（1） Chondrocytes were treated with interleukin 1β（IL-1β） to establish the OA model in vitro

and were divided into the ICA+PRP group

ICA group

PRP group and IL-1β group. Chondrocyte proliferation（CCK-8） and apoptosis（flow cytometry） were observed. The levels of tumor necrosis factor-α（TNF-α） were detected by enzyme-linked immunosorbent assay.（2） Thirty New Zealand white rabbits were selected

and 6 were selected as the normal group; the New Zealand white rabbit knee joint OA model was established by surgery

and the rabbits were divided into the model group

ICA+PRP group

ICA group and PRP group

with 6 cases in each group. The expressions of Wnt1

β-catenin and glycogen synthase kinase 3β（GSK-3β） were analyzed by western blotting. RESULTS:（1） Compared with the control group

the levels of TNF-α in ICA+PRP group

ICA group and PRP group decreased significantly

the differences were statistically significant（P<0.05）. The proliferation activity of ICA+PRP group was significantly better than that of ICA group and PRP group

and the apoptosis rate of ICA+PRP group was significantly lower than that of ICA group and PRP group

with statistically significant differences（P<0.05）. The proliferation activity and apoptosis rate of ICA group were significantly better than those of PRP group

the differences were statistically significant（P<0.05）.（2） The Osteoarthritis Research Society International（OARSI） score of ICA+PRP group was significantly better than that of ICA group and PRP group

and the differences were statistically significant（P<0.05）. Compared with the normal group

the mRNA and protein expressions of β-catenin and Wnt1 in cartilage of the model group increased

while the mRNA and protein expressions of GSK-3β decreased

with statistically significant differences（P<0.05）. Compared with the model group

the mRNA and protein expressions of Wnt and β-catenin in ICA+PRP group and ICA group decreased significantly

and the mRNA and protein expressions of GSK-3β increased significantly

with statistically significant differences（P<0.05）; and the effect of ICA+PRP group was better than that of ICA group. CONCLUSIONS: ICA combined with PRP can play an anti-OA effect by promoting chondrocyte proliferation

inhibiting inflammatory injury and cell apoptosis

and Wnt/β-catenin signaling pathway is closely involved in this process.