STUDY OF POTENTIAL NEUROTOXIC EFFECTS OF ACRYLAMIDE ON THE CEREBELLUM IN ADULT ALBINO RATS

Abstract

Background: Acrylamide (ACR) is an industrial pollutant, an exposure to acrylamide via different routes causes selective neurotoxicity. Aim of the Work: This work was performed to study potential neurotoxic effects of acrylamide on the cerebellum in adult albino rats by evaluation of neurobehavioral functional observational tests (gait score, landing hind limb foot splay), histopathological and immunhistochemichal testing of cerebellum. Materials and Methods: This study was carried out on 48 adult male albino rats which divided into 4 equal groups; GroupI (negative control group), Group II (positive control group) GroupIII (low dose acrylamide): Subdivided into two equal subgroups( III a& IIIb ) : each rat was gavaged orally with daily dose of 8.5mg/kg acrylamide for 4 & 8 weeks respectively. Group IV (high dose acrylamide): Subdivided into two equal subgroups( IV a& IV b ) : each rat was gavaged orally with daily dose of 17 mg/kg acrylamide for 4 & 8 weeks respectively. Results: There was a significant increase in both mean rank and mean values of gait scores and landing hind limb foot splay of both treated groups as compared to those of control groups. There was a strong positive correlation between foot splay and gait score, Microscopic examination of H&E stained of cerebellum of both treated groups showed loss of purkinjie cells, ACR affections were dose and time dependent . Silver stained cerebellar sections of rats received low dose for 4 weeks showed loss of some Purkinje cells, other rats received low dose for 8 weeks or high dose showed loss of most Purkinjie cells and the fibers of the white matter were seen with progressive fragmentation. Immunolocalization of Glial Fibrillary Acidic Protein (GFAP) in the cerebellum of treated groups showed progressive distribution of GFAP-positive astrocytes which was dose and time dependent. There was a strong positive correlation between area percentage and landing hind limb foot splay, a moderate positive correlation between area percentage and gait score. Conclusion: Acrylamide has a neurotoxic effect clarified by impairment of gait score and increase in landing hind limb foot splay. The abnormal neurobehavioral functional observational tests were associated to cerebellar histopathological changes in the form of selective loss of purkinjie cell, axonapathy and gliosis. Recommendation: it is recommended to increase public awareness about the health impact of exposure to acrylamide.