Biološka važnost pretjerane ekspresije HSP70 i alfa-B kristalina u supstanciji nigri štakora izloženih različitim dozama permetrina

Abstract

The aim of this study was to investigate the possible role of the Heat Shock Protein 70 (HSP70) and Alpha B-crystallin (αBC) in the substantia nigra of rats exposed to permethrin at different doses on the apoptotic cell status. The orogastric gavage method was used to administer the different doses of permethrin (75 mg kg-1 in Group I, 150 mg kg-1 in group II, 300 mg kg-1 in group III) to the rats. Using the Western blot test, all the permethrin-treated groups showed a dose-dependent increase in the expression of HSP70 and αBC when compared to the control group. TUNEL positive apoptotic cells were not detected in the dopaminergic neurons of the substantia nigra after treatment with permethrin; however, upon immunofluorescent staining, intense positive reactions for HSP70 and αBC were observed in all of the treated groups. No immunopositive cells were detected in the tissue sections of the control group. These results suggest that the different administered doses of permethrin did not cause apoptotic cell death in the substantia nigra dopaminergic neurons; however, they did induce an increase in HSP70 and αBC expression. Thus, it appears that HSP70 and αBC could play a neuroprotective role in permethrin-induced neurotoxicitySvrha ove studije bila je istražiti moguću ulogu proteina toplinskog stresa 70 (HSP70) i alfa-B kristalina (αBC) u supstanciji nigri (lat. substantia nigra) štakora izloženih različitim dozama permetrina na apoptotske stanice. Metoda orogastričnog hranjenja upotrijebljena je kako bi se štakorima dale različite doze permetrina (75 mg kg-1 u skupini I, 150 mg kg-1 u skupini II, 300 mg kg-1 u skupini III). Nakon provođenja analize Western blot sve skupine kojima je dan permetrin pokazale su, ovisno o dozi, povećanje ekspresije HSP70 i αBC u usporedbi s kontrolnom skupinom. Apoptotske stanice pozitivne na TUNEL-test nisu otkrivene u dopaminergičkim neuronima supstancije nigre nakon tretmana permetrinom. Međutim nakon imunofl uorescentnog bojenja za HSP70 i αBC primijećene su snažne pozitivne reakcije u svim tretiranim skupinama. U tkivu kontrolne skupine nije bilo imunopozitivnih stanica. Naši rezultati upućuju na to da različite doze permetrina nisu uzrokovale apoptozu dopaminergičkih neurona supstancije nigre, ali su izazvale povećanje ekspresije HSP70 i αBC. Stoga bi HSP70 i αBC mogli imati pozitivan neuroprotektivni učinak pri neurotoksičnosti izazvanoj permetrinom