Objective To observe the effects of moxibustion on p53

cystine/glutamate antiporter solute carrier family 7 member 11(SLC7 A11)

and glutathione peroxidase 4(GPX4) in synovial tissues of rats with adjuvant arthritis(AA)

so as to explore the mechanism of moxibustion in alleviating rheumatoid arthritis. Methods Eighty rats were randomly divided into normal

model

moxibustion

and medication groups(n=20 in each group). The AA model was established by exposure to wind

cold

and damp environmental factors combined with injection of complete Freund's adjuvant. Rats in the moxibustion group received suspended moxibustion at “Shenshu”(BL23) and “Zusanli”(ST36) alternately

while those in the medication group were treated with tripterygium glycoside tablet suspension(8 mg/kg) by gavage

once a day

for 15 successive days. The pathological change in synovial tissue of rat right knee joint was observed by HE staining. The protein and mRNA expression levels of p53

SLC7 A11

and GPX4 in the synovial tissue were detected by Western blot and quantitative real-time PCR

respectively. The se-rum glutathione(GSH) and reactive oxygen species(ROS) contents were measured by colorimetry and fluorescence probe me-thod. Results Compared with the normal group

the model group exhibited synovial hyperplasia of the right knee joint

massive inflammatory cell infiltration

up-regulated mRNA and protein expression of p53 in synovial tissue

elevated serum ROS content(P<0.01)

down-regulated mRNA and protein expression of SLC7 A11 and GPX4 in synovial tissue

and lowered serum GSH content(P<0.01). Comparison with the model group showed that the synovial injuries in the moxibustion and medication groups were obviously alleviated. The mRNA and protein expression levels of p53 in the synovial tissues and the serum ROS content declined significantly(P<0.01)

while the mRNA and protein expression of SLC7 A11 and GPX4 in the synovial tissues and the se-rum GSH content increased(P<0.01). There was no significant difference in histopathological change of synovial tissue between the moxibustion group and medication group. However

the p53 protein expression in the synovial tissue and the level of serum ROS were significantly higher in the medication group than in the moxibustion group(P<0.05)

while the GPX4 protein expression and serum GSH content were down-regulated(P<0.05). Conclusion Moxibustion improves the inflammatory response in synovial tissue of AA model rats

which may be closely related to its regulation of the expression of ferroptosis-related factors.