Dehydroandrographolide alleviates rheumatoid arthritis by inhibiting neutrophil activation via LMIR3 in collagen induced arthritis rats

ABSTRACT

Rheumatoid arthritis (RA) is an inflammatory disease which causes severe pain and disability. Neutrophils play essential roles in the onset and progression of RA; thus, inhibition of neutrophil activation is becoming a popular therapeutic strategy. Dehydroandrographolide has provided satisfactory outcomes in inflammatory diseases; however, its therapeutic effects and mechanism in RA are not fully understood. Leukocyte mono-immunoglobulin-like receptor 3 (LMIR3) is a negative regulator highly expressed in neutrophils. To determine whether dehydroandrographolide negatively regulated neutrophils activation via LMIR3, cytokines release and collagen-induced arthritis (CIA) rats were used in vitro and in vivo. Biacore, molecular docking analysis and molecular dynamics simulation were performed to prove the target of dehydroandrographolide. Moreover, the downstream signaling pathways of LMIR3 activation were analyzed by western blotting. Results showed that oral dehydroandrographolide administration of 2 mg/kg/day to CIA rats attenuated synovitis and bone and cartilage damage after the 28-day intervention, revealed using HE sections and micro-CT. Dehydroandrographolide significantly inhibited cytokine release and chemotaxis of LPS/TNF-α-activated neutrophils in vitro. Dehydroandrographolide inhibited neutrophils activation via binding to LMIR3. Moreover, dehydroandrographolide up-regulated the phosphorylation of SHP-1 and SHP-2, which are the essential kinases in the LMIR3 signaling pathways. This study revealed that dehydroandrographolide attenuated collagen-induced arthritis by suppressing neutrophil activation via LMIR3.

KEYWORDS:

• Rheumatoid arthritis
• dehydroandrographolide
• LMIR3

Acknowledgements

We acknowledge M.D. candidates Yutian Lei, Yiwei Zhao and Peng Tian from Department of Bone and Joint Surgery, Xi’an Jiaotong University Second Affiliated Hospital for the assistance in animal experiments. We thank the National Local Joint Engineering Research Center for Precision Surgery & Regenerative Medicine and Shaanxi Province Center for the animal operation room. Regenerative Medicine and Surgery Engineering Research for providing the We acknowledge Editage for language editing.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contributions

KN: Conceptualization, Methodology, Investigation, Software, Writing – Original Draft. GHS: Investigation, Data curation, Writing- Original draft preparation. DXD: Methodology, Investigation. CRM: Visualization, Investigation. LH: Methodology, Investigation. XFZ: Visualization, Investigation. DXS: Investigation, Formal analysis. ZY: Investigation, Data Curation, Software, Validation. ZL: Software. LZY: Software, Validation. TR: Visualization, Validation. LYY: Investigation, Resources. WKZ: Supervision. CDL: Supervision, Writing – Review & Editing. YP: Supervision, Funding acquisition, Project administration, Writing – Review & Editing.

Data availability statement

The datasets generated and/or analyzed during the current study are available from the corresponding author by reasonable request.

Ethical approval

The animal study was reviewed and approved by the Animal Experiment Ethics Committee of Xi’an Jiaotong University, China (No. XJTULAC2020–1370).

Additional information

Funding

This work was supported by Key Project for Science Research and Development of Shaanxi Province (2019ZDLSF03-07).