Résumé
Interferon alpha [IFN-alpha] therapy is used considerably in Egypt because of a high prevalence rate of chronic hepatitis C virus infection. Alpha-Lipoic acid [ALA] has been found to play a neuroprotective role in many insults. The aim of this study is to observe the histological structure of the topic nerve of rats after an injection of IFN-alpha and to determine the role of ALA supplementation. Forty adult male albino rats were divided equally into four groups. Group I served as the control group. Group II included rats that received ALA alone [100mg/kg/day, intraperitoneally]. Group III included rats that received IFN-alpha alone [100000 IU/kg/three times/week, intraperitoneally]. Group IV included rats that received both IFN-alpha and ALA. After 8 weeks, the optic nerves were extirpated and processed for light and electron microscope examination. Optic nerves of the group that received IFN-alpha showed nerved damage manifested as axonal damage and changes in the myelin sheath. Neuroglia showed vacuolation in their cytoplasm and heterochromatic nuclei. Morphometric and statistical analyses showed a significant increase in the surface area of positive glial fibrillary acidic protein astrocytes, indicating reactive astrogliosis. Blood capillaries were distorted with ill-defined walls and protrusion of the endothelial cells into their lumina. These changes were limited by concomitant ALA supplementation with IFN-alpha. IFN-alpha exerted a deleterious effect on the histological structure of the optic nerve in rats and ALA supplementation minimized these effects