Objective To observe the effect of moxibustion on the indicators of autophagy and apoptosis in the synovium of toes of rats with adjuvant-induced arthritis(AA)

so as to explore the underlying mechanism of moxibustion in the treatment of rheumatoid arthritis. Methods Forty-five SD rats were randomly divided into the blank control group

model group

moxibustion group

methotrexate group and rapamycin group

with 9 rats in each group. The rat model of AA was established by injecting Freund's complete adjuvant. Rats in the moxibustion group received moxibustion treatment at “Zusanli”(ST36) and “Guanyuan”(CV4) for 20 min

once a day. The methotrexate group was given methotrexate intragastrically(0.35 mg/kg) twice a week. The rapamycin group was given rapamycin by intraperitoneal injection(1 mg/kg)

once every other day. The toe volume of the left hind limb was measured by the toe volume measuring instrument after 3-day modeling and 3-week intervention respectively. The contents of interlukin(IL)-1 and tumor necrosis factor(TNF)-α in serum were detected by ELISA. The autophagosomes of synovial cells of the toe joint were observed under transmission electron microscope. The expressions of mammalian target of rapamycin(mTOR)C1

p-mTORC1

Caspase-3

Fas and FasL in synovial tissue were detected by Western blot. Results Under transmission electron microscope

the model group showed decreased autophagosomes in synovial tissues

but the moxibustion

methotrexate

and rapamycin groups showed increased autophagosomes. Compared with the blank control group

the toe volume

the contents of IL-1 and TNF-α in serum and the expression of p-mTORC1 protein in synovial tissue were significantly increased(P<0.01

P<0.001)

while the expressions of Caspase-3

Fas and FasL proteins in synovial tissue were significantly decreased(P<0.05

P<0.01) in the model group. Compared with the model group

the toe volume

the contents of IL-1 and TNF-α in the serum

and expression of p-mTORC1 protein were significantly decreased(P<0.05

P<0.01

P<0.001) in the moxibustion group and the methotrexate group

while the expression of Caspase-3

Fas and FasL proteins in synovial tissue in the moxibustion group and the methotrexate group

the expression of Caspase-3 in the rapamycin group were significantly increased(P<0.05). Conclusion Moxibustion can improve joint swelling in AA rats and decrease the contents of serum IL-1 and TNF-α. The mechanism may be related to regulating the expressions of p-mTORC1

Caspase-3

Fas and FasL proteins

and promoting autophagy and apoptosis of synovial cells.