Effects of drynaria total flavonoids on serum levels of leptin,interleukin 6, prostaglandin E2 and expression of bone β2-adrenergic receptor in ovariectomized osteoporosis rats

AIM: To investigate the effects of drynaria total flavonoids on serum levels of leptin (LEP), interleukin 6(IL-6), prostaglandin E₂(PGE₂) and the expression of bone β₂-adrenergic receptor (ADRB2) in a rat model of ovariectomized osteoporosis(OP). METHODS: The osteoporosis model was established by ovariectomy. Twelve weeks after modeling,bone mineral density (BMD) was determined by dual-energy X-ray absorptiometry to verify successful modeling.Enzyme-linked immunosorbent assay was applied to detect the concentrations of LEP, IL-6 and PGE₂ in serum. The expression of ADRB2 was determined by immunohistochemical technique. RESULTS: Compared with sham group,BMD of the rats in model group significantly decreased in multiple regions 12 weeks after modeling(P<0.01). The serum levels of LEP, IL-6 and PGE₂ in model group were significantly higher than those in sham group(P<0.05). The levels of LEP, IL-6 and PGE₂ in drynaria total flavonoids group were significantly lower than those in model group(P<0.01). No significant difference of PGE₂ between these 2 groups was observed. The ADRB2 expression in sham group and treatment group was significantly different from that in model group, and no significant difference between sham group and treatment group was found. CONCLUSION: The serum levels of LEP, IL-6 and PGE₂ and the expression of bone ADRB2 increased in OP rats.Drynaria total flavonoids reduce the production of LEP, IL-6 and the expression of ADRB2, and suppress the bone absorption, which may be one of the mechanisms in treating OP.