Low-level sodium arsenite induces apoptosis through inhibiting TrxR activity in pancreatic β-cells.

In our previous study, we reported that sodium arsenite induced ROS-dependent apoptosis through lysosomal-mitochondrial pathway in pancreatic β-cells. Since the thioredoxin (Trx) system is the key antioxidant factor in mammalian cells, we investigate whether the inhibition of Trx system contributes to sodium arsenite-induced apoptosis in this study. After treatment with low-level (0.

Sodium arsenite induces ROS-dependent autophagic cell death in pancreatic β-cells.

Inorganic arsenic is a worldwide environmental pollutant. Inorganic arsenic's positive relationship with the incidence of type 2 diabetes mellitus arouses concerns associated with its etiology in diabetes among the general human population. In this study, the inhibitor of autophagosome formation, 3-methyladenine, protected the cells against sodium arsenite cytotoxicity, and the autophagy stimulator rapamycin further decreased the cell viability of sodium arsenite-treated INS-1 cells.

Perfluorooctane sulfonate blocked autophagy flux and induced lysosome membrane permeabilization in HepG2 cells.

Perfluorooctane sulfonate (PFOS) is an emerging persistent organic pollutant widely distributed in the environment, wildlife and human. In this study, as observed under the transmission electron microscope, PFOS increased autophagosome numbers in HepG2 cells, and it was confirmed by elevated LC3-II levels in Western blot analysis. PFOS increased P62 level and chloroquine failed to further increase the expression of LC3-II after PFOS treatment, indicating that the accumulation of autophagosome was due to impaired degradation rather than increased formation.

The role of oxidative stress in citreoviridin-induced DNA damage in human liver-derived HepG2 cells.

We hypothesize that citreoviridin (CIT) induces DNA damage in human liver-derived HepG2 cells through an oxidative stress mechanism and that N-acetyl-l-cysteine (NAC) protects against CIT-induced DNA damage in HepG2 cells. CIT-induced DNA damage in HepG2 cells was evaluated by alkaline single-cell gel electrophoresis assay. To elucidate the genotoxicity mechanisms, the level of oxidative DNA damage was tested by immunoperoxidase staining for 8-hydroxydeoxyguanosine (8-OHdG); the intracellular generation of reactive oxygen species (ROS) and reduced glutathione (GSH) were examined; mitochondrial membrane potential and lysosomal membranes' permeability were detected; furthermore, protective effects of NAC on CIT-induced ROS formation and CIT-induced DNA damage were evaluated in HepG2 cells.

Genotoxic effects induced by zearalenone in a human embryonic kidney cell line.

Mycotoxins are considered to be significant contaminants of food and animal feed. Zearalenone (ZEA) is a hepatotoxic mycotoxin with estrogenic and anabolic activity found in cereal grains worldwide. ZEA affects hematological and immunological parameters in humans and rodents.

[Mechanism of the apoptosis of rat pancreas islet β cell strain (INS-1 cells) induced by sodium arsenite].

Objective: To study mechanism of the apoptosis of rat pancreas islet β cell strain (INS-1 cells) induced by sodium arsenite.

Methods: INS-1 cells were exposed to sodium arsenite at the different concentrations. MTT assay was used to detect the viability of INS-1 cells.

β-Elemene radiosensitizes lung cancer A549 cells by enhancing DNA damage and inhibiting DNA repair.

β-Elemene is a broad-spectrum antitumor agent. In China, several studies have indicated that β-elemene enhances the cytotoxic effect of radiation in vitro and in vivo. In this study, the alkaline comet assay and neutral comet assay were used to measure both DNA strand breaks and DNA repair activity in A549 cells exposed to β-elemene, irradiation or combination treatment.

Lysosomal membrane permeabilization contributes to elemene emulsion-induced apoptosis in A549 cells.

Elemene is a broad-spectrum antitumor agent. In the present study, lysosomal membrane permeabilization (LMP) was detected after short elemene emulsion--exposure (12 h) that preceded a decrease of the mitochondrial membrane potential and DNA damage (24 h) in A549 cells. At later time points (36 h) elemene emulsion caused the appearance of A549 cells with apoptotic features, including apoptotic morphology, phosphatidylserine exposure, and caspase-3 activation.

Patulin-induced oxidative DNA damage and p53 modulation in HepG2 cells.

Patulin (PAT) is a mycotoxin produced by certain species of Penicillium and Aspergillus. The aim of this study was to assess PAT-induced DNA damage and to clarify the mechanisms, using human hepatoma G2 (HepG2) cells. PAT caused significant increase of DNA migration in single cell gel electrophoresis assay.

Patulin-induced genotoxicity and modulation of glutathione in HepG2 cells.

Patulin (PAT), a mycotoxin produced by certain species of Penicillium, Aspergillus and Byssochlamys, is mainly found in ripe apple and apple products. In our present study, a significant increase of the micronuclei frequency induced by PAT was found in human hepatoma HepG2 cells. To elucidate the role of glutathione (GSH) in the effect, the intracellular GSH level was modulated by pre-treatment with buthionine-(S, R)-sulfoximine (BSO), a specific GSH synthesis inhibitor, and by pre-treatment with N-acetylcysteine (NAC), a GSH precursor.

Curcumin attenuates acrylamide-induced cytotoxicity and genotoxicity in HepG2 cells by ROS scavenging.

Acrylamide (AA), a proven rodent carcinogen, has recently been discovered in foods heated at high temperatures. This finding raises public health concerns. In our previous study, we found that AA caused DNA fragments and increase of reactive oxygen species (ROS) formation and induced genotoxicity and weak cytotoxicity in HepG2 cells.

Curcumin induces apoptosis through mitochondrial hyperpolarization and mtDNA damage in human hepatoma G2 cells.

Curcumin, a major pigment of turmeric, is a natural antioxidant possessing a variety of pharmacological activities and therapeutic properties. But its mechanisms are unknown. In our previous study, we found that a 2-h exposure to curcumin induced DNA damage to both the mitochondrial DNA (mtDNA) and the nuclear DNA (nDNA) in HepG2 cells and that mtDNA damage was more extensive than nDNA damage.

Curcumin-induced genotoxicity and antigenotoxicity in HepG2 cells.

Curcumin, a polyphenolic yellow pigment found in turmeric, is commonly used as a coloring agent in foods, drugs, and cosmetics. In our previous study, we found that low levels of curcumin did not increase the reactive oxygen species (ROS) formation and caused no damage to DNA in human hepatoma G2 (HepG2) cells, but at high doses, curcumin imposed oxidative stress and damaged DNA. In the present study, we are determined to investigate the genotoxic and antigenotoxic effects of curcumin using HepG2 cell line, a relevant in vitro model to detect the cytoprotective, antigenotoxic, and cogenotoxic agents.

Mitochondrial and nuclear DNA damage induced by curcumin in human hepatoma G2 cells.

Curcumin is extensively used as a spice and pigment and has anticarcinogenic effects that could be linked to its antioxidant properties. However, some studies suggest that this natural compound possesses both pro- and antioxidative effects. In this study, we found that curcumin induced DNA damage to both the mitochondrial and nuclear genomes in human hepatoma G2 cells.