Crocin Rich Extract of Nyctanthes arbor-tristis Flower Calyx Induces Anti-angiogenic Activity

Crocin is an apocarotenoid present in Nyctanthes arbortrisits (NAT) flower calyx extract in abundant quantity of about 36.7% w/w. The carotenoid rich extract of NAT exhibited dose dependant anti-angiogenic effect in chick-chorioallantoic membrane (CAM) assay. The anti-angiogenic activity of NAT extract (1 mg/ml) was observed to be equivalent to Heparin (1 mg/ml) with the IC50 value of 0.5 mg/ml. The antiangiogenic activity of NAT was further confirmed by in-vivo Matrigel Matrix model of Balb/c mice with VEGF inhibitor, sunitinib malate (1 μM) as the anti-angiogenic control. The in-vivo study revealed significant (P<0.01) reduction in hemoglobin levels and inhibited angiogenesis as compared to angiogenic control viz. VEGF loaded matrigel matrix. The anti-angiogenic activity of NAT calyx ethanolic extract is likely to be due to the presence of Crocin since carotenoids possess inherent strong anti-oxidant potential. Our result brings out a new naturally occurring anti-angiogenic agent which may find its utility in the treatment of conditions like cancer, diabetic retinopathy and cataract.