Bacopa monnieri extracts prevent hydrogen peroxide-induced oxidative damage in a cellular model of neuroblastoma IMR32 cells / 中国天然药物

Neurodegenerative diseases are the consequences of imbalance between the production of oxidative stress and its nullification by cellular defense mechanisms. Hydrogen peroxide (HO), a precursor of deleterious reactive oxygen species, elicits oxidative stress, resulting in severe brain injuries. Bacopa monnieri is well known for its nerve relaxing and memory enhancing properties. The present study was designed to evaluate the protective effects of extracts from Bacopa monnieri against HO induced oxidative stress using a cellular model, neuroblastoma IMR32 cell line. The protective potential of methanolic, ethanolic, and water extracts of B. monnieri (BM-MEx, BM-EEx, and BM-WEx) was evaluated using MTT assay. Although, all the B. monnieri extracts were found to protect cells against HO-mediated stress but BM-MEx showed significantly greater protection. UPLC analysis of BM-MEx revealed various polyphenols, including quercetin, catechin, umbelliferone, and caffeic acid predominance. Further, BM-MEx was found to possess considerable greater neuroprotective potential in comparison to the standard polyphenols such as quercetin, catechin, umbelliferone, and caffeic acid. The levels of antioxidant enzymes were significantly elevated after the pretreatment of BM-MEx and quercetin. The expression levels of oxidative stress markers, such as NF200, HSP70, and mortalin, were significantly alleviated after the pretreatment of BM-MEx as shown by immunofluorescence and RT-PCR. In conclusion, the present study demonstrated the protective effects of BM-MEx, suggesting that it could be a candidate for the development of neuropathological therapeutics.

Expression of Mortalin in human hepatoma-derived cell lines and its role in epithelial-mesenchymal transition / 中华肝胆外科杂志

Objective To detect the expression of Mortalin in human hepatoma-derived cell lines and explore its effect on epithelial-mesenchymal transition in hepatocellular carcinoma (HCC) cell lines.Methods Six HCC cell lines and 1 normal liver cell line (L02) were chosen.The expression of Mortalin was detected using Western blot and real-time quantitative PCR (qPCR).The endogenous gene expression of Mortalin was inhibited by RNA interference (shRNA).Cell viability was detected using MTT assay and flow cytometry.The expression of Mortalin,E-cadherin and Vimentin were detected by Western blot and qPCR.The experiment was divided into three groups; blank,control,and shRNA.Results Mortalin was detected in Hep3B,MHCC97H,HepG2,and HCCLM3,but not in MHCC97L and L02.After 24 h transfection,GFP fluorescence showed that plasmid Mortalin shRNA was successfully transfected into MHCC97H cells.MTT assay indicated that cytotoxicity was 0％,2.5％,and 3.5％ in the blank,control,and shRNA group respectively.Similarly,flow cytometric showed that early apoptosis rates were 0.8％,4.5％,and 9.2％ in the blank,control,and shRNA group respectively.These results indicated that transfection did not cause severe cell damage.After 48 h of interference,Western blot and qPCR analysis showed that shRNA significantly inhibited the expression of Mortalin.Moreover,cells were collected after 24 h,48 h,72 h and 96 h of interference and analyzed for the relationship between Mortalin,E-cadherin and Vimentin by Western blot and qPCR.It was found that decreased expression of Mortalin was accompanied by elevated E-cadherin expression and reduced Vimentin expression.Conclusion Overexpression of Mortalin correlated with the metastatic phenotype of HCC cells and could promote epithelial-mesenchymal transition.

Mortalin promotes ovarian cancer cell growth through MAPK-ERK signal pathway / 解剖学报

Objective By constructing mortalin stably expressing ovarian cancer cell lines in A 2780 and A2780/cis, we demonstrate the role of mortalin in the ovarian cancer cell growth .Methods CCK-8 assay was used to measure cell viability in the overexpression mortalin group compared with the control group .The flow cytometry analysis was used to understand the effect of upregulated mortalin on the ovarian cancer cell cycle .Western blotting was used to determine the expression and phosphorylation level of MAPK /ERK and JNK/SAPK signal pathways .Results The results showed that increased expression of mortalin could accelerate ovarian cancer cell proliferation and promote G 1 transition, leading to a faster restoration of normal distribution of cell cycle .We found that mortalin overexpression significantly activated p-Raf and p-ERK1/2, but not p-JNK.Conclusion The results demonstrate that mortalin effect on the ovarian cancer cell proliferation contributes to active the MAPK-ERK signaling pathway .

Neuroprotective Effect of Convolvulus pluricaulis Methanol Extract on Hydrogen Peroxide Induced Oxidative Stress in Human IMR32 Neuroblastoma Cell Line.

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.