The effects of resveratrol on mitochondrial biogenesis dysfunction induced by fluoride in human neuroblastoma SH-SY5Y cells / 中华劳动卫生职业病杂志

Objective@#To explore the role of mitochondrial biogenesis and the neuroprotective mechanism of resveratrol in fluoride neurotoxicity.@*Methods@#SH-SY5Y cells in exponential phase were treated with different concentrations (20, 40, 60 mg/L) of sodium fluoride (NaF) for 24 h. Co-treatment with 60 mg/L NaF, 20 μmol/L resveratrol (RSV) was administrated in the resveratrol intervene trial. Western blotting was used to determine the expression levels of mitochondrial biogenesis key regulating factor of peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α) , nuclear respiratory factor 1 (NRF1) and mitochondrial transcription factor A (TFAM) in SH-SY5Y cells. The mRNA levels of PGC-1α, NRF1 and TFAM were determined by Quantitative Real-time PCR in SH-SY5Y cells, as well as the relative mitochondrial DNA (mtDNA) contents and mRNA expression of mitochondrial respiratory chain complexes subunit CO1 and ATP8. Flow cytometry was used to determine mitochondrial membrane potential in SH-SY5Y cells.@*Results@#Both the protein and mRNA levels of PGC-1α, NRF1 and TFAM were decresed after 60 mg/L NaF treatment in SH-SY5Y cells (P<0.05) . The relative mtDNA contents and mRNA expression of complexes subunit CO1 and ATP8 were also significantly decreased compared with control (P<0.05) . Mitochondrial membrane potential were also significantly decreased after 60 mg/L NaF treatment in SH-SY5Y cells (P<0.05) . Compared with 60 mg/L NaF group, the protein and mRNA levels of PGC-1α, NRF1 and TFAM in 20 μmol/L RSV+60 mg/L NaF group were significantly increased (P<0.05) . The relative mtDNA contents, mitochondrial membrane potential and mRNA levels of complexes subunit CO1 and ATP8 in 20 μmol/L RSV+60 mg/L NaF group were also significantly higher than that in 60 mg/L NaF group (P<0.05) .@*Conclusion@#Resveratrol may alleviate the fluoride-induced mitochondrial biogenesis dysfunction in SH-SY5Y cells.

Enhancement of Arsenic Trioxide (As2O3)-Mediated Apoptosis Using Berberine in Human Neuroblastoma SH-SY5Y Cells

OBJECTIVE: Arsenic trioxide (As2O3) has been used as an anticancer agent in traditional Chinese medicine for thousand years and berberine is an isoquinoline alkaloid present that has indicated significant antimicrobial activity. We have examined the combined anticancer effects of As2O3 and berberine against the human neuroblastoma (HNB) SH-SY5Y cells in vitro, and to elucidate underlying molecular mechanism. METHODS: HNB SH-SY5Y cells were treated with 2 microM As2O3 and 75 microgram/ml berberine, and their survival, cell death mechanism as well as synergistic cytotoxic effects were estimated by using MTT assay, DAPI staining, agarose gel electrophoresis, flow cytometric analysis, and western blot analysis. RESULTS: The combined treatment of two drugs also markedly decreased cell viability. The cytotoxic effects of two drugs were revealed as apoptosis characterized by chromatin condensation, DNA fragmentation, and the loss of mitochondrial membrane potential. The apoptotic cytotoxicity was accompanied by activation of caspase-3 protease as well as decreased the expression of Bcl-2, Bid, and Bcl-x/L. In addition, the cells treated with combination of two drugs also showed significantly increased intracellular reactive oxygen species levels and lipid peroxidation compared to cells As2O3 or berberine only. CONCLUSION: Combined treatment of As2O3 with berberine induced activation of apoptotic signaling pathways in HNB SH-SY5Y cells. These results suggest that the possibility of the combined treatment of two chemotherapeutic agents with low concentration improving cytotoxic effect for cancer cells with minimal side effects.

The c-myc expression on the opioid tolerance in human neuroblastoma SH-SY5Y cells

The mechanisms underlying opiate tolerance and dependence are not fully understood. We used human neuroblastoma SH-SY5Y cells as a model system for studying effects of morphine tolerance and withdrawal on c-myc induction and cAMP levels. It has been reported that regulation of c-fos by acute and chronic morphine withdrawal is mediated through alterations in CREB transcription factor. In this study, we examined the effects of morphine tolerance on c-myc expression and cAMP concentrations. The activation of opiate receptors by an acute morphine administration resulted in an increase in c-myc mRNA and a decrease in cAMP concentrations in a dose-dependent manner (5, 10, 15, and 20 muM). On the other hand, the chronic treatment of morphine (10 muM for six days) did not induce the elevated expression of c-myc mRNA. The c-myc expression was slightly inhibited in comparison with that of the acute morphine response. However, cAMP concentrations were increased with regard to morphine withdrawal response. These results suggest that the alterations in c-myc expression might imply a significant opiate regulation relating to morphine tolerance. This observation differs from increased expression of c-fos via regulation of cAMP pathway.