Effect of Fengshi Qutong Capsules on synovial angiogenesis in rats with type Ⅱ collagen induced arthritis / 中国中药杂志

ABSTRACT

To observe the effect of Fengshi Qutong Capsules(FSQTC) on angiogenesis of rat aortarings and in knee joint synovium of type Ⅱ collagen-induced arthritis(CIA) rats. The blood vessel of aorta rings of normal SD rats were induced by vascular endothelial growth factor(VEGF) 20 μg·L~(-1 )in vitro, and were treated with FSQTC(0.02, 0.1 and 0.5 μg·L~(-1)) continuously for 9 days. The number, length and area of neovascularization of the vascular ring were measured. SD rats were immunized to establish collagen-induced arthritis. CIA rats were treated with FSQTC(0.25, 0.5, 1 g·kg~(-1)·d~(-1)) and methotrexate(0.2 mg·kg~(-1)·d~(-1)) daily for 19 days. Histopathological examination(HE) was performed to observe the vascular morphology and vascular density in the synovial membrane of the inflamed joint. Immunohistochemistry was performed to observe the expression of platelets-endothelial cell adhesion molecule(CD31), VEGF and VEGF receptor 2(VEGFR_2)in the synovium. Immunofluorescence was performed to observe the expression of CD31 and α smooth muscle actin(αSMA) in synovial membrane.TGF-β, PDGF and VEGFR_2 in serum were detected by enzyme-linked immunosorbent assay. The number, branch length and area of blood vessels of aorta rings were significantly increased induced by VEGF, and FSQTC could significantly reduce the number, branch length and area of blood vessels. Compared with the normal group, the vascular density, CD31 positive expression, CD31~+/αSMA~- immature and total vascular positive expression in the synovial membrane of the model group were significantly increased, and so as VEGF and VEGFR_2 in the synovium. The VEGFR_2, TGF-β and PDGF in sera were also significantly increased in model group. FSQTC reduced the synovial vascular density and inhibited the positive expression of CD31, CD31~+/αSMA~- immature blood vessels and total vascular. FSQTC has no significant effect on CD31~+/αSMA~+mature blood vessels. FSQTC also negatively inhibited the expression of VEGF, VEGFR_2, TGF-β and PDGF in synovial membrane and/or sera. The effect of methotrexate is similar with to the high dose group. Our results demonstrated that FSQTC could inhibit the angiogenesis of synovial tissue in CIA rats and of aortaring in rats, which is related to the reduction of angiogenesis regulatory factor.