Abstract

Oxidative stress induced by chronic administration of Efavirenz on the intracranial visual relay centers of adult Wistar rats

JO Adjene, JA Avbunudiogba, PS Igbigbi

The biochemical effects of chronic administration of efavirenz commonly used as part of highly active antiretroviral therapy (HAART) for the treatment of Human Immunodeficiency Virus (HIV) type-1 on the intracranial visual relay centres (namely superior colliculus and lateral geniculate body) of adult Wistar rats were carefully studied. The rats of both sexes (n=30), with an average weight of 200g were randomly assigned into treatment (n=15) and control (n=15) groups. The rats in the treatment group received the recommended dose of 600mg/70kg body weight of efavirenz dissolved in distilled water daily for 30 days (thirty days) through the orogastric tube. The control group received equal volume of distilled water daily for 30 days through the same route. The rats were fed with growerâ????s mash obtained from Edo Feeds and Flour Mill Limited, Ewu, Edo state, Nigeria and given water liberally. The rats were sacrificed by cervical dislocation method on the thirty-first day of the experiment and the superior colliculus and lateral geniculate body were carefully dissected out, weighed using the Mettler Toledo weighing balance and homogenized. The homogenates were centrifuged at 3500rpm for 5 minutes and the clear supernatants were collected using a micropipette which was then transferred into an empty specimen container and refrigerated till needed for the biochemical assays. The findings indicated that the Malonyldialdehyde (MDA) and Superoxide Dismutase (SOD) were consistent. MDA as a non-enzyme biomarker of oxidative stress is higher on the treated tissues, with statistically significant (P<0.05) difference observed. SOD is consistently lower in the treated tissues with statistical significant (P<0.05) difference as compared with the control group in this experiment. Chronic administration of efavirenz may therefore have an adverse effect on the visual sensibilities by affecting the superior colliculus and lateral geniculate body of adult Wistar rats.