The effects of amphotericin B on angiogenesis in chick chorioallantoic membrane

Amphotericin B (AmB) is widely used as a mainstay in the treatment of sight-threatening fungal endophthalmitis. From the time that itraconazole was discovered to have a previously unknown anti-angiogenic activity, we have suspected that AmB may have possible effects on ocular angiogenesis. The purpose of this study was to evaluate the in vivo anti-angiogenic effect of AmB in the chick chorioallantoic membrane (CAM) model.

Atak-S type fertilized eggs obtained from the Poultry Institution were used. The eggs were kept under 37 °C at 85-90% relative humidity throughout the experiment. Amphotericin B was prepared in two different concentrations (AmB 125 μg/1 mL and 0.125 μg/1 mL). The CAMs treated with sterile distilled water was specified as controls. About 0.1 mL of each containing 12.5 and 0.0125 µg of AmB, respectively, were dropped to CAM surface. Thirteen eggs were used for each group. The results were evaluated at the 48th hour of the administration of the drugs and recorded by digital camera.

A reduction of angiogenesis in CAM area which treated with 125 μg/1 mL of AmB was appreciable macroscopically. The affected areas showed impaired radial arrangement of small vessels with the presence of avascular zone at periphery. The dose of 0.125 μg/1 mL AmB did not show any visible anti-angiogenic effect. Numerous blood vessels with a radially arranged pattern developed toward the periphery after 48 h of treatment. In the CAMs that treated with distilled water, physiological angiogenesis was observed in allantoic vessels. Vessel formation seems to be similar in CAMs treated with 0.125 μg/1 mL AmB with the presence of visibly non-malformed alive embryos.

The present study gives the impression that AmB has the capacity to serve as an anti-angiogenic treatment. As it is a preliminary CAM study only, further studies on both animals and humans are required.