Effects And Mechanisms Of Apoptosis Induced By Bioactive Peptides Of Neonatal Bovine Brain In Peak Ⅰ On The Human Neuroblastoma SK-NH-SH Cells

In this study, we used NBBP-1, a group of peptides which isolated from acid extracts of neonatal bovine brain, through a CM Sepharose CL-6B column to treat the Human neuroblastoma SK-NH-SH cells. We investigated the biological effects and the antitumor mechanisms of NBBP-1 by the methods of cell biology, immune biology, biochemistry and molecular biology.The results revealed that the proliferation of SK-N-SH cells were inhibited apparently after being treated with 60μg/mL NBBP-1, the growth of cells were inhibited, the cell mitotic index was declined obviously, the cell cycle came into apoptosis. Light microscopy, transmission electron microscopy showed that SK-N-SH cells, which induced with NBBP-1, had lost their original malignant phenotype which were different from those of untreated cells but were similar to those of normal apoptotic cells: the cells, including cell shrinkage, nuclear condensation, compaction and margination of nuclear chromation, and formation apoptotic bodies. Flow cytometry analysis showed NBBP-1 could induce the emergence of the peak of apoptosis. Immunocytochemistry revealed that the expression of Wtp53, Bax, Fas were upregulated significatntly while the products of Bcl-2 proteins were downregulated significantly in the cells treated with NBBP-1.Taken together, the results of the current study showed that NBBP-1 could effectively inhibit the proliferation of the human neuroblastoma SK-N-SH cells, induce DNA-damage, sub-G0/G1 cells and classic apoptosis morpholigical and ultrastructural characteristics. All of this showed NBBP-1 could induce the emergence of the phase of apoptosis. Therefore it indicated that NBBP-1 has an obvious apoptosis inducing effect on the human neuroblastoma cells by regulating the expression of oncogenes and tumor suppressors genes such as bcl-2, wtp53, fas and bax genes.