OBJECTIVE To investigate the application of Psammosilenes Radix(a commonly used traditional Chinese medicinal herb in Yunnan folk medicine for treating rheumatic arthralgia) in modern treatment of rheumatoid arthritis(RA), and to explore the mechanism of action of its ethanol extract.

METHODS  collagen-induced RA mouse model was used, and the dosage of each administration group was continuously administered for 21 d. Foot swelling and arthritis scores, histopathological staining, and ELISA were used to detect the tumor necrosis factor-α(TNF-α) content in mouse serum. Western blotting was used to determine the expression of activator of transcription factor 6(ATF-6), glucose-regulated protein 78(GRP78), and C/EBP homologous protein(CHOP) proteins in mouse ankle joints; real-time fluorescence quantitative nucleic acid amplification detected the mRNA expression of ATF-6, GRP78, and CHOP in cells.

RESULTS  Each administration group significantly reduced foot swelling, arthritis scores, and serum pro-inflammatory factor TNF-α content in collagen-induced RA mice(P<0.01), histopathological examination results showed that each administration group improved the joint damage of collagen-induced RA mice, reduced knee arthritic cell infiltration, and the expression of ATF-6 and GRP78 protein and mRNA in the ankle joint Significantly reduced(P<0.01), CHOP protein and mRNA expression significantly increased(P<0.05).

CONCLUSION  It is suggested that reducing the inflammatory response in RA mice by regulating the endoplasmic reticulum stress pathway may be the potential of Psammosilenes Radix to improve RA synovial inflammation mechanism.