OBJECTIVETo investigate expression features and correlation of genes expression on MyD88-dependent signaling pathway in synovial membrane (SM) of progression of knee osteoarthritis (OA).

METHODSSixty Wistar rats were randomly divided into 6 groups, including blank group (N), false surgical group, model groups[2 weeks (2W), 4 weeks (4W), 8 weeks (8W) and 12 weeks (12W)], with 10 rats in each group. The models were established by using Hulth method. Control group was experienced no surgery, while false surgical group was only opened joint cavity and sutured. The SM samples was collected according to the time designed above. The relative expression quantity of MyD88, TLR4 and NF-κB was detected by Real-time PCR after the extraction of the total RNA and reverse transcription. The correlation analysis was obtained by SPSS.

RESULTSThere was no significant difference in each gene mRNA expression between false surgical and blank group(> 0.05), while enhanced expression was found in the model groups(<0.05). The correlation index among MyD88, TLR4 and NF-κB was 0.91 and 0.86 respectively, and had significant difference among them.

CONCLUSIONSPositively relative among MyD88, TLR4 and NF-κB played main role in TLR4/NF-κB signal passway, and could predicate the expression of other genes in the passway. It also could further provide the basis for clarify the pathologic mechanism of knee OA.