ABSTRACT
Aims: The present study aimed to evaluate and ascertain the protective role of methanolic/ethanolic/water extracts of Convolvulus pluricaulis against H2O2 induced cytotoxicity in IMR32 Neuroblastoma cell line as model system and identify the factor responsible for the protective effect. Study Design: Experimental study. Place and Duration of Study: Department of Molecular Biology and Biochemistry, Guru Nanak Dev University, Amritsar & Department of Biotechnology, DAV College, Amritsar, PuCPab, between August 2010 and March 2012. Methodology: Firstly, cytotoxic dose of H2O2 and non-toxic dose of methanolic, ethanolic and water extracts of C. pluricaulis (CP-MEx, CP-EEx and CP-WEx respectively) was determined by MTT assay. Protective effect of CP-MEx, CP-EEx and CP-WEx was determined using quercetin as a positive control. The expression of IMR32 cytoskeletal marker, Neurofilament (NF-200) and stress markers, Heat shock protein (HSP70) and (glucose regulated protein 75, Grp75) Mortalin studied by immunofluorescence and RTPCR results. The level of antioxidant enzymes catalase, superoxide dismutase, glutathione peroxidase, direct scavenger of free radicals, Glutathione and lipid peroxidation were analysed by their standard procedures. Results: The results showed that quercetin, CP-MEx, CP-EEx and CP-WEx displayed cytoprotective activity in IMR32 cells. Out of tested extracts CP-MEx significantly decreased hydrogen peroxide-induced cell death. Significant decrease in NF-200, HSP70 and Mortalin expression was observed in CP-MEx+H2O2 treated cultures as compared to H2O2 treated. Catalase, superoxide dismutase, glutathione peroxidase, Glutathione levels significantly increased in Quercetin and CP-MEx treated cultures. Lipid peroxidation was significantly decreased in both Quercetin and CP-MEx treated cultures. Conclusions: The present work establishes the protective effect of CP-MEx on IMR 32 Human Neuroblastoma cell line which is as much as by quercetin. The cytoprotective effect of CP-MEx was due to induction of antioxidant machinery of the cell hence holds therapeutic value in the treatment and/or prevention of neurodegenerative disorders of oxidative stress.