Ethanol extract of dendrobium chrysotoxum Lindl. On the amelioration of diabetic retinopathy and its engaged mechanism / 国际药学研究杂志

ABSTRACT

Objective To observe the ethanol extract from Dendrobium chrysotoxum Lindl. (DC) on the amelioration of diabetic retinopathy (DR) in mice induced by streptozotocin (STZ), and further investigate the engaged mechanism. Methods Diabetes was induced by STZ injection in C57 mice and then the diabetic mice were orally given with DC. The retinal neovascularization was evaluated by staining with cluster of differentiation 31 (CD31) and histological assessment of retinas by hematoxylin-eosin (HE) staining. The mRNA expression of signals involved in vascular endothelial growth factor (VEGF) signaling pathway was detected by realtime PCR assay. The amount of VEGF in serum and vitreous bodies was detected by enzyme-linked immunosorbent assay (ELISA). Results DC (50 and 200 mg/kg) reduced the increased retinal vessels in STZ-induced diabetic mice. Results of real-time PCR showed that DC reduced the increased mRNA expression of retinal hypoxia inducible factor-1α (HIF-1α), VEGF and its receptors including VEGFR1 and VEGFR2 in STZ- induced diabetic mice. ELISA results further demonstrated that DC reduced the increased VEGF level in serum and vitreous bodies of STZ-induced diabetic mice. Conclusions DC ameliorates DR via inhibiting retinal angiogenesis by reducing the expression of VEGF and VEGF-regulated signaling pathway.