Based On The TLR4/MyD88/NF-κB Signaling Pathway, The Mechanism Of Oral Administration Of Zhuifeng Tougu Capsules To Reduce Cartilage Degeneration In Rabbit Knee Osteoarthritis Model Was Investigated

Objective:To observe the effect of oral administration of Zhuifeng Tougu capsule on the expression of TLR4/MyD88/NF-κB signaling pathway and related inflammatory factors in the articular cartilage tissue of rabbit knee osteoarthritis model,To explore the possible mechanism of oral administration of ZhuifengTougu capsule to slow down the degeneration of articular cartilage in rabbit knee osteoarthritis model.Methods:Using 506-month-old male New Zealand rabbits,10 were randomly selected as the normal group using a random number table method,and the remaining 40 were KO A group,The modified Videman modeling method was used to immobilize the left lower limb of the rabbit in KOA model group with an extended position for 6 weeks to prepare a rabbit KOA model.After successful validation of KOA model,they were randomly regrouped,the random method is the same as before,six rabbit were randomly selected from the remaining normal group as the blank group(groupA),thirty rabbits were randomly selected from the remaining KOA model group and then randomly divided into model group(groupB),Glucosamine sulfate group(groupC),ZhuifengTougu capsule low-dose group(group D),ZhuifengTougu capsule middle dose group(groupE),Zhuifeng Tougu capsule high-dose group(groupF),Six in each group.Start the administration on the second day after the completion of the second grouping,group A and group B were given distilled water by gavage,group C was given Glucosamine Sulfate Suspension by gavage,Group D,E and F were given the corresponding dose of ZhuifengTougu capsule suspension by intragastric administration,the course of treatment was 6 weeks.After administration,rabbits were killed by air embolization and samples were collected.Gross and HE staining were performed to observe the cartilage of knee joint on the modeling side of rabbits,Pelletier’s score and Mankin’s score were used for evaluation.The knee joint cartilage on the modeling side was taken as the specimen,the expressions of TLR4、MyD88 and NF-κB were detected by Western Blot,the mRNA expression of TLR4,MyD88and NF-κB was detected by RT-qPCR,the levels of IL-1β,IL-6 and TNF-α were determined by immunohistochemistry.Results:Compared with the blank group,the cartilage of the knee joint in the model group was obviously damaged,Pelletier’s score and Mankin’s score are all increased(P<0.01),mRNA and protein expression levels of TLR4,MyD88 and NF-κB in cartilage were all up-regulated(P<0.01),The levels of IL-1β,IL-6 and TNF-ain cartilage were all increased(P<0.01).Compared with the model group,The degree of cartilage damage in the low、middle and high-dose groups of ZhuifengTougu capsules and the glucosamine sulfate group was mild,the Pelletier’s scores of cartilage were all reduced,Mankin’s scores decreased(P<0.01),mRNA and protein expression levels of TLR4,MyD88 and NF-κB in cartilage were all down-regulated(P<0.01),the levels of IL-1β,IL-6 and TNF-α in cartilage are all decreased(P<0.01),Among them,the Pelletier’s score of cartilage in the ZhuifengTougu capsule high-dose group was significantly reduced(P<0.0 5),The difference is statistically significant.Conclusion:ZhuifengTougu capsules taken orallycan can delay the degeneration of articular cartilage in rabbit KOA model induced by modified Videman modeling method.The mechanism might be is by down-regulating the mRNA and protein expressions of TLR4,MyD88 and NF-κB in cartilage tissue,decrease the content of activated products IL-1β,IL-6 and TNF-α in cartilage,thereby reducing the inflammatory response.