Objective: To investigate the effect of Huangqi Guizhi Wuwutang (HGW) on joint synovial cell apoptosis in rat models with collagen induced arthritis (CIA)

and explore its mechanism of action. Method: The 72 SD rats were randomly divided into 6 groups: normal group (N)

model group (CIA)

HGW low

medium and high dose groups (HGW-L

M

H)

and Tofacitinib group (TFN). The drug doses were 16

32

64 g·mL-1 respectively in HGW-L

HGW-M

HGW-H(16

32

64 g·kg-1) groups equivalent to 3

6

12 times of the dosage for clinical common people; the drug dose of TFN was 15 mg·kg-1; 10 mL·kg-1 distilled water was given daily in normal group and model group. Bovine typeⅡcollagen and Freund's complete adjuvant (FCA) were used to build collagen-induced arthritis rat models

and the ankle pathological morphology in rats was observed under light microscope after 4 weeks treatment by HGW. Then the contents of IL-10 and IL-4 were detected by flow cytometry. The protein expression levels of Bcl-2 and Bax were detected by immunohistochemistry

and terminal dexynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) staining was used to detect the apoptosis of synovial cells. Result: As compared with normal group

the protein expression levels of Bcl-2 in synovium were increased in model group

HGW-L

M

H groups and TFN group (P<0.05); the protein expression levels of Bax were reduced in model group (P<0.05). As compared with model group

Bcl-2 protein expression levels were decreased in HGW-H group and TFN group

while Bax protein expressions were increased (P<0.05).Apoptosis of synovial cells was visible

and as compared with normal group

synovial cells were increased in model group

HGW-L

M

H groups and TFN group

with a decreased apoptosis rate (P<0.05). As compared with model group

the apoptosis rate of synovial cells was increased in HGW-L

M

in H groups and TFN group (P<0.05). As compared with HGW-L group

apoptosis rate of synovial cells was significantly increased in HGW-H group (P<0.01); as compared with HGW-M group

apoptosis rate of synovial cells was increased in HGW-H group (P<0.05). Conclusion: Huangqi Guizhi Wuwutang can promote the apoptosis of synovial cells with abnormal hyperfunction in RA rats.