OBJECTIVETo investigate the effects of Danshen Injection (DSI) on the proliferation of rheumatoid arthritis fibroblast-like synoviocytes (RA FLSs) cultured in RA patients' serum.

METHODSThe RA FLSs harvested from RA patients' synovial fluid were primarily cultured by routines. The cells were cultured with 10% inactivated human serum (the healthy human serum and the RA patients' serum) for 24 h. Then DSI at the final concentration of 0. 4 mg/mL was added in the cells for further 24 h culture. By taking 10% fetal calf serum as the control, the morphological changes were observed under optical microscope. The proliferation was analyzed by MTT. The apoptosis was detected by flow cytometry. The total RNA was extracted and reverse transcription was performed. The Bax mRNA expression was detected by fluorescent quantitative PCR.

RESULTS(1) After human serum was added in the healthy human serum and RA patients' serum, cells could grow adhering to the wall. Compared with the fetal calf serum group (FCS), the cell density was higher in the healthy human serum group than in the fetal calf serum group, with no obvious morphological changes. (2) MTT results showed that, compared with the fetal calf serum group, the absorbance value (OD) obviously increased in the healthy human serum group and the RA patients' serum group, showing statistical difference (P <0.01). After adding DSI at the final concentration of 0.4 mg/mL, cells from different serums were inhibited to various degrees (with OD significantly decreased, P <0.05). The OD value significantly increased more in the healthy human serum group and the RA patients' serum group than in the fetal calf serum group, showing statistical difference (P <0.01). There was statistical difference between the healthy human serum group and the RA patients' serum group (P <0.01). (3) The apoptosis rate in the RA patients' serum group obviously decreased with statistical difference, when compared with the Salvia miltiorrhiza free fetal calf serum group (P >0. 01). The apoptosis rate in the fetal calf serum group and the RA patients' serum group significantly increased after adding 0.4 mg/mL Salvia miltiorrhiza, showing statistical difference when compared with the Salvia miltiorrhiza free fetal calf serum group and the Salvia miltiorrhiza free RA patients' serum group (P <0.05). The FLSs were effected by 0.4 mg/mL Salvia miltiorrhiza, the apoptosis rate significantly decreased in the healthy human serum group and the RA patients' serum group, showing statistical difference when compared with the fetal calf serum group (P <0. 05, P <0.01). (4) The expression of Bax gene significantly increased in the RA patients' serum group and the fetal calf serum group after action of 0.4 mg/mL Salvia miltiorrhiza, showing statistical difference (P <0. 01). When 0.4 mg/mL Salvia miltiorrhiza was added, the expression of Bax mRNA obviously increased in the healthy human serum group and the RA patients' serum group, showing statistical difference when compared with the fetal calf serum group (P <0.01).

CONCLUSIONS(1) Although healthy human serum can be favorable to the growth of RA FLSs, the fetal calf serum could reflect the actual results better in the cyto biological research on specific diseases (if there is no serum from patients with corresponding disease). (2) DSI could inhibit the proliferation of RA FLSs through promoting their apoptosis.