Study on the Molecular Mechanism of Matrine in Improving Rheumatoid Arthritis by Targeting the NAV2-Wnt3a/β-catenin Axis to Coordinately Regulate the Inflammatory-Osteolytic Loop

Qianyu GuoMeie LiangZhen LiJie LiKe XuLiyun Zhang^*

• Third Hospital of Shanxi Medical University, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences，Tongji Shanxi Hospital，  Taiyuan, 030032, China, Taiyuan, China

Background: The occurrence and development of rheumatoid arthritis (RA) is closely related to bone erosion caused by abnormal activation of Wnt3a/β-catenin signaling pathway. However, it is unclear how the natural product matrine (MAT) targets and regulates this pathway at the molecular mechanism level. This study focuses on the role of NAV2, a novel neuronal guidance protein, in RA, and systematically analyzes the immunomodulatory mechanism of MAT. Methods: the collagen type II-nduced arthritis (CIA) model in Wistar rats was established by the combined induction of bovine collagen type II and Freund's adjuvant. Twenty-four rats were randomly divided into four groups: normal control group (NOR), model group (CIA), methotrexate treatment group (MTX) and matrine treatment group (MAT). Four weeks of in vivo administration. The arthritis index (AI) and paw swelling degree were dynamically monitored, and the changes of ankle joint bone quality related indicators and serum cytokines were detected. Mic-CT was used to measure the destruction of articular bone, HE staining and O-fast green staining were used to evaluate synovial inflammation and articular cartilage damage. Liver and kidney toxicity markers were detected to evaluate drug safety. qRT-PCR and Western blotting were used to detect the mRNA and protein expression levels of NAV2, Wnt3a and β-Catenin in rat joints, respectively. In addition, immunohistochemical techniques were used for localization analysis. Results: MAT could significantly reduce the arthritis index of CIA rats (P < 0.01), reduce the level of pro-inflammatory cytokines (P < 0.05), significantly increase the level of anti-inflammatory cytokines, and effectively improve the indicators of joint bone erosion, while there was no significant difference in liver and kidney function indicators between mat group and healthy control group. Mat significantly inhibited the mRNA and protein expression of NAV2, Wnt3a and β-catenin in rat joints (all P < 0.05). After the intervention with mat, the positive areas of these three molecules decreased significantly (p<0.01). Conclusion: MAT plays a dual regulatory role by inhibiting NAV2-wnt3a/ β-Catenin signal transduction pathway, restoring the balance of inflammatory cytokine network, and has drug safety. Mat may become a new candidate drug for the treatment of RA.