cytochrome-c-t and dioscin

The anti-cancer effects of dioscin have been widely reported. However, its effect on laryngeal cancer remains unknown. In the present paper, our results showed that dioscin markedly caused cell apoptosis and DNA damage, increased reactive oxygen species (ROS) level, induced S-phase arrest, and inhibited invasion of human laryngeal cancer HEp-2 and TU212 cells. Mechanism investigation showed that dioscin markedly up-regulated p53 level, and down-regulated cyclin-dependent kinase 2 (CDK2) and Cyclin A levels. In addition, dioscin significantly down-regulated the levels of p-ERK, Bcl-2, up-regulated the levels of p-JNK, p-p38, Bax, cleaved caspase-3/-9, and caused Cytochrome c release. Furthermore, U0126, an ERK1/2 inhibitor, markedly down-regulated Bcl-2 level, up-regulated the levels of Bax, cleaved caspase-3/9, and enhanced Cytochrome c release inducted by dioscin. While, SP600125 (one JNK inhibitor) and SB203580 (one p38 inhibitor) markedly up-regulated Bcl-2 level, down-regulated the levels of Bax, cleaved caspase-3/9, and obviously boosted Cytochrome c release induced by dioscin. Interestingly, dioscin also markedly down-regulated the levels of MMP2 and MMP9 associated with tumor invasion. Taken together, our study indicated that dioscin suppressed laryngeal cancer cells growth via inducting cell-cycle arrest, MAPK-mediated mitochondrial- derived apoptosis and inhibiting tumor invasion, which could be used as one potential candidate for the treatment of laryngeal cancer in the future.

Topics: Antineoplastic Agents; Apoptosis; Caspase 3; Cell Cycle Checkpoints; Cell Line, Tumor; Cell Movement; Cell Proliferation; Cell Survival; Cytochromes c; Diosgenin; DNA Damage; Humans; Laryngeal Neoplasms; MAP Kinase Signaling System; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Mitochondria; Mitogen-Activated Protein Kinases; Neoplasm Invasiveness; Protein Kinase Inhibitors; Reactive Oxygen Species

To determine if dioscin protects cardiac cells from ischemia/reperfusion (I/R) injury by preventing apoptosis.Cardiac H9c2 cells were subjected to simulated I/R. Cell viability was evaluated by the methyl thiazolyl tetrazolium (MTT) colorimetry assay. Reactive oxygen species (ROS) were detected with dichlorodihydrofluorescein (DCF). Apoptosis was evaluated with flow cytometric assay. Rhodamine 123 (Rho123) was used to measure mitochondrial membrane potential (ΔΨm). ELISA was used to detect cytochrome c (Cyt-c) release from mitochondria to the cytosol. Bax and Bcl-2 mRNA expressions were measured with RT-PCR.Dioscin reduced cell death and lactate dehydrogenase (LDH) release in cells subjected to I/R. I/R induced apoptosis and cytochrome c release from mitochondria to the cytosol and this was prevented by dioscin. In support, dioscin decreased Bax but increased Bcl-2 mRNA expression. Dioscin prevented I/R induced dissipation of ΔΨm. Finally, dioscin increased superoxide dismutase (SOD) expression but reduced intracellular ROS and malondialdehyde (MDA) levels.Dioscin protects H9c2 cells from H/R injury by modulating the mitochondrial apoptotic pathway through attenuation of oxidative stress.

Topics: Animals; Antioxidants; Apoptosis; bcl-2-Associated X Protein; Cardiovascular Agents; Cell Line; Coloring Agents; Cytochromes c; Diosgenin; Enzyme-Linked Immunosorbent Assay; Flow Cytometry; L-Lactate Dehydrogenase; Malondialdehyde; Membrane Potential, Mitochondrial; Mitochondria; Myocardium; Myocytes, Cardiac; Oxidative Stress; Proto-Oncogene Proteins c-bcl-2; Rats; Reactive Oxygen Species; RNA, Messenger; Superoxide Dismutase; Tetrazolium Salts; Thiazoles

In the present study, the antiproliferative effect of dioscin on human gastric carcinoma SGC-7901 cells was confirmed by 3-(4, 5-dimethylthiahiazo-zyl)-2, 5-dip-henytetrazolium bromide and flow cytometry assays. Through acridine orange-ethidium bromide double fluorescent staining, apoptotic morphology of the cells was observed. Radioimmunoassays showed that the tumor necrosis factor (TNF)-α concentration in cells treated with dioscin significantly increased compared with untreated cells. Several proteins and mRNA related to the mitochondrial and death receptor pathways were investigated. We found that the expression of Bid, bcl-2 and bcl-xl was markedly downregulated, and the expression of Bak and Bax was upregulated. In addition, cytochrome c was released from the mitochondria into the cytosol, which indicates activation of the mitrochondrial pathway by dioscin. Furthermore, upregulation of Fas, FasL (Fas ligand), TNF-α, TNF receptor-1, TNF receptor-associated factor 1 and Fas-associated protein with death domain demonstrated involvement of the death receptor pathway. Increased mRNA expression of p53 was also found in dioscin-treated SGC-7901 cells, and the activation of caspase-3 and -8 was also observed. Consequently, this study clarifies the mechanism underlying the anticancer effect of dioscin, and also indicates that dioscin may be a potential drug treatment for human gastric cancer.

Topics: Antineoplastic Agents; Apoptosis; bcl-2 Homologous Antagonist-Killer Protein; bcl-2-Associated X Protein; BH3 Interacting Domain Death Agonist Protein; Caspase 3; Caspase 8; Cell Line, Tumor; Cell Proliferation; Cytochromes c; Diosgenin; Down-Regulation; Fas Ligand Protein; fas Receptor; Humans; Mitochondria; Radioimmunoassay; RNA, Messenger; Tumor Necrosis Factor-alpha; Tumor Suppressor Protein p53; Up-Regulation

Study of the mechanisms of apoptosis in tumor cells is an important field of tumor therapy and cancer molecular biology. Apoptosis triggered by activation of the mitochondrial-dependent caspase pathway represents the main programmed cell death mechanism. The mitochondrial-dependent apoptosis pathway is activated by various intracellular stresses that induce permeabilization of the mitochondrial membrane, leading to cytochrome C release. This study was to investigate the anti-tumor effects of Dioscin from traditional Chinese anti-snake venom medicine Paris chinensis (PCD) and correlated mechanisms regarding apoptosis in human ovarian cancer SKOV3 cells.. Cell viability was analyzed by the 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyl-tetrazolium bromide (MTT) assay. Cell apoptosis was evaluated by flow cytometry and Laser Scanning Confocal Microscope (LSCM) using Annexin-V/PI staining. Intracellular calcium ions were detected using fluorescence microscopy. The expression of apoptosis-related proteins cytochrome C and caspase-3 was measured by immunohistochemical staining.. PCD had an anti-proliferation effect on human ovarian cancer SKOV3 cells in a dose- and time-dependent manner. After treatment with PCD, the apoptotic rate significantly increased, and accompanied with the increased levels of caspase-3 and cytochrome C protein in SKOV3 cells. Morphological changes typical of apoptosis were also observed with LSCM by Annexin V/PI staining. Moreover, intracellular calcium accumulation occurred in PCD-treated cells.. The molecular determinants of inhibition of cell proliferation as well as apoptosis of PCD may be associated with the activation of Ca2+-related m itochondrion pathway in SKOV3 cells.

Topics: Apoptosis; Calcium; Caspase 3; Cell Line, Tumor; Cell Proliferation; Cell Survival; Cytochromes c; Diosgenin; Drugs, Chinese Herbal; Female; Humans; Mitochondria; Mitochondrial Membranes; Ovarian Neoplasms; Permeability; Trillium