Neuroprotective Effect of Total and Sequential Extract of Scrophularia striata Boiss. in Rat Cerebellar Granule Neurons Following Glutamate- Induced Neurotoxicity: An In-vitro Study

Abstract

Neuroprotective effect of the extract from aerial parts of Scrophularia striata Boiss(Scrophulariaceae) was investigated against glutamate-induced neurotoxicity on cultured rat pupsCerebellar Granule Neurons (CGNs). CGNs from 8 days old Sprague-Dawley rat were preparedand cultured. The experiments were performed after 8 days in culture. The plant was collected fromthe northeastern part (Ruin region) of Iran and air-dried at room temperature. The total extract wasprepared with maceration of prepared powder in ethanol 80% for three times. Sequential extractswere obtained using dried and powdered aerial parts with increasingly polar solvents: petroleumether, chloroform, ethyl acetate and methanol 80% solution. Cultured cells were exposed to 125μM of glutamate for 12 h following a 24 h of incubation with test fractions at concentrationof 10 mcg/mL. Morphological assay was performed using invert light microscope after fixationand staining with haematoxylin. Neuronal viability was measured using MTT assay. Statisticalanalysis was done using SPSS software. One way analysis of variance (ANOVA) was performedby Tukey post-hoc test. Values were considered statistically significant when p-value ≤ 0.05.Results of this study showed a significant neuroprotective activity of high polarity methanolicfraction of aerial parts of Scrophularia striata against glutamate-induced neurotoxicity in a dosedependentmanner. Treatment with 10 mcg/mL of the fractions showed the best result.