[Effects of Drynaria total flavonoids on apoptosis of osteoblasts mediated by tumor necrosis factor-α].

OBJECTIVE: To investigate the influence of Drynaria total flavonoids on proliferation and apoptosis of osteoblasts in tumor necrosis factor-α (TNF-α)- mediated medium, so as to explore the mechanism of Drynaria total flavonoids in preventing and treating osteoporosis of rheumatoid arthritis.

METHODS: Twenty Wistar rats with average weight of (200±20) g were randomly divided into two groups: blank control group and Qianggu capsule (Drynaria total flavonoids) group. Rats in Qianggu capsule group were fed with 75 mg Qianggu capsule daily for continuous 3 d. One hour after the last feed, blood samples were collected. The in vitro experiment of four groups was designed: blank control serum group, Drynaria total flavonoids-containing serum group, blank control serum plus TNF-α group and Drynaria total flavonoids-containing serum plus TNF-α group. Methyl thiazolyl tetrazolium method was used to detect the proliferation of osteoblasts. Flow cytometry was used to detect the apoptosis of osteoblasts and real-time fluorescent quantitative polymerase chain reaction to detect the expressions of Bcl-2 and Bax mRNAs in osteoblasts.

RESULTS: Compared with the control serum, Drynaria total flavonoids-containing serum promoted the proliferation and decreased the apoptosis of osteoblasts in TNF-α-mediated inflammatory environment (P<0.05), and increased the ratio of Bcl-2 mRNA to Bax mRNA.

CONCLUSION: In TNF-α-mediated inflammatory environment, Drynaria total flavonoids can promote the proliferation and decrease the apoptosis of osteoblasts by improving the ratio of Bcl-2 mRNA to Bax mRNA, which may be one of the mechanisms of Drynaria total flavonoids in preventing and treating osteoporosis of rheumatoid arthritis.