The effect of intracerebroventricular amyloid beta 1-42 application on cognitive functions in aged rats supplemented with taurine and the change of peroxisomal proteins in this process.

Abstract

Objective: The aim of our study is to investigate the change of peroxisomal proteins in the neurodegenerative and oxidative process caused by the neurotoxicity of A beta 1 & ndash;42 in aged rats supplemented with taurine and to show the possible positive effects of taurine in this process.

Methods: 30 Wistar albino rats were randomly divided into 5 groups as control, sham, A beta 1 & ndash;42, taurine, and A beta 1 & ndash;42+taurine. Taurine administration continued for 6 weeks (1000 mg/kg/day with drinking water). Stereotaxic surgery was applied to all groups (intracerebroventricular per lateral ventricle needle only or 5 mu l, PBS, or A beta 1 & ndash;42). Spatial learning and memory performances of the animals were evaluated with Morris water maze and elevated plus maze. The levels of MDA and GSH were measured as oxidative stress parameters in the cerebral cortex and hippocampus. Expressions of CAT, PEX14, PMP70 of peroxisomal membrane proteins were indicated by Western blot analysis.

Results: Our results showed that injection of A beta 1 & ndash;42 decreased the spatial learning and memory performance, cortex CAT and hippocampus PEX14, PMP70 and GSH levels, and increased cortex and hippocampus MDA levels (p < 0.05). Although the administration of taurine partially ameliorated the adverse effects of A beta 1 & ndash;42 injection, a significant difference was found only at the hippocampus GSH levels (p < 0.05). Also, taurine caused anxiety at this dose (p < 0.05).

Discussion: In conclusion, decreased peroxisomal proteins and antioxidant capacity in neurodegenerative and oxidative processes induced by intracerebroventricular A beta 1 & ndash;42 injection showed that peroxisomes may play a role in this process and taurine supplementation may have positive effects especially in increasing antioxidant capacity.