Therapeutic Effect And Mechanism Of Bionic Tiger Bone Powder On Mice With Collagen-Induced Arthritis

Objective: Rheumatoid arthritis(RA)is a common immune-mediated chronic inflammatory disease that can lead to irreversible joint deformities and functional impairments.Chronic inflammation and bone erosion are the two core pathogenic events of RA.Tiger bone,as a precious and rare traditional Chinese medicine,has a long history of application in bone and joint diseases such as osteoporosis,RA,and osteoarthritis.However,its substitute biomimetic formula,bionic tiger bone powder,has only been widely used in clinical practice to treat osteoporosis.In order to explore the potential application of bionic tiger bone powder in the treatment of RA,this study used collagen-induced arthritis(CIA)mice as an animal model to simulate the development of RA,observed the effect of bionic tiger bone powder on chronic inflammation and bone erosion in CIA mice,and explored its potential mechanisms of action.Methods: A CIA mouse model was constructed using bovine type II collagen immunization.The mice were randomly divided into CIA model group,positive control group(MTX),low-dose bionic tiger bone powder group(JTG-L),medium-dose bionic tiger bone powder group(JTG-M),high-dose bionic tiger bone powder group(JTG-H),and normal group(Normal)as control,with 10 mice in each group.The positive control group was treated with methotrexate,while the low,medium,and high-dose bionic tiger bone powder group were administered by gavage with the corresponding dose and frequency.During the medication period,the general condition,joint arthritis score,and body weight changes of each group of mice were observed and recorded.After 3 weeks of administration,the mice were euthanized to collect blood and ankle joint specimens.The levels of pro-inflammatory cytokines,tumor necrosis factor-alpha(TNF-α),interleukin-6(IL-6),matrix metalloproteinase-2(MMP-2),and MMP-9 in mouse serum were detected by ELISA.The ankle joint slices of the mice were prepared and observed using H&E and Safranin O-fast green staining to evaluate the degree of inflammation,cartilage,and bone damage.Immunohistochemistry staining staining was used to observe the expression levels of TNF-α,osteopontin(OPN),nuclear factor kappa B(NF-κB),and NF-κB receptor activator ligand(RANKL)in ankle joint tissues.Results:1.The CIA model group of mice exhibited significant swelling and congestion of the ankle joint,sustained weight loss,and increased arthritis score.Compared to the CIA model group,the bionic tiger bone powder treatment groups of mice showed improvement in weight loss and a significant decrease in arthritis score(P<0.001).2.H&E staining of the ankle joint revealed that the bionic tiger bone powder treatment groups of mice had significantly improved synovial inflammation cell infiltration and proliferation compared to the CIA model group,with a significant reduction in pathological inflammation scores observed in the medium and high dose groups(P<0.005 or P<0.001).The results of Safranin O-Fast Green staining showed that the bionic tiger bone powder treatment groups of mice exhibited a significant reduction in cartilage damage,with a significant decrease in Mankin’s scores observed in the medium and high dose groups(P<0.001).3.Immunohistochemistry staining showed that the expression levels of TNF-α in the synovium of the ankle joint in the bionic tiger bone powder treatment groups of mice were significantly downregulated(P<0.01 or P<0.001).The expression levels of RANKL and OPN in the ankle joint of mice were significantly reduced in the medium-and high-dose bionic tiger bone powder group(P<0.005 or P<0.001).The expression levels of NF-κb in the ankle joint of mice were significantly reduced in the high-dose bionic tiger bone powder group(P<0.001).4.The levels of serum TNF-α,IL-6,MMP-2,and MMP-9 in the bionic tiger bone powder treatment groups were decreased to varying degrees compared to the CIA model group,with a significant effect on the down-regulation of IL-6,TNF-α,MMP-9,and MMP-2 in the high-dose bionic tiger bone powder group(P<0.005 or P<0.001).Conclusion:1.Bionic tiger bone powder effectively inhibits CIA-induced joint inflammation in mice by reducing levels of pro-inflammatory cytokines IL-6,TNF-α,MMP-9 and MMP2 in mouse serum,downregulating TNF-α and OPN expression levels in synovial tissue,and relieving synovial inflammation and hyperplasia.2.Bionic tiger bone powder can effectively improve cartilage damage and bone destruction in CIA mice,possibly through the inhibition of the RANKL/NF-κB pathway.3.Bionic tiger bone powder has a certain therapeutic effect on CIA mice and may become a potential treatment for RA.