pyloriexposure for 3 hours changed the Bax/Bcl-2 proportion of AGS cells

pyloriexposure for 3 hours changed the Bax/Bcl-2 proportion of AGS cells. epithelial cell apoptosis. As a result, it is possible that DEHP andH. pyloricoexposure might enhance the disruption of the gastric mucosa integrity and potentially promote the pathogenesis of gastric carcinogenesis. == 1. Introduction == Di(2-ethylhexyl)phthalate (DEHP) is the most common plasticizer used to increase the flexibility of polyvinyl chloride (PVC). DEHP is often used for the development of flexible plastics in food-packaging, plastic flooring, carpet material, roofing materials, plastic wall treatments, indoor decorations, wire, cable packaging materials, and children’s toys [1]. DEHP is also used as a cleaner, industrial solvent, wetting agent, and lubricant [2]. Human exposure to DEHP usually occurs through air, water, or skin contact with DEHP-contained plastics [3]; however, the most common source of exposure is due to the ingestion of contaminated packaged foods. Due to its chemical structure, DEHP can readily dissolve and seep from the packaging materials into the food [24]. Phthalate exposure can have many potential health effects in humans. For example, a previous study reported that DEHP and mono-2-ethylhexyl phthalate (MEHP) can SNX-2112 pass through the placenta and shorten the gestational period of a developing fetus [5]. DEHP also delays the development of the SNX-2112 male reproductive system [2]. Recent evidences also show prenatal DEHP exposure is associated with shorter gestation [6], but prenatal DEHP exposure does not affect birth outcomes [7]. Even though oral ingestion of DEHP is one of the most common routes of exposure in humans, the effects of this toxin on gastric epithelial cells have not been fully elucidated. The human gastric pathogen,Helicobacter pylori(H. pylori), is a spiral Gram-negative microaerophilic bacterium, which can selectively colonize the mucus layer of the stomach and can cause severe gastric problems including the development of chronic gastritis, peptic ulcers, and gastric cancer [8].H. pyloriis often transmitted to human through a variety of ways, including oral-oral and fecal-oral routes [9].H. pyloriinfection induces apoptosis, of gastric SNX-2112 epithelial cells, an effect which was reported with both in vivo [10,11] and in vitro studies [1214]. Plastics are widely used in food packaging in Taiwan and the world; however, DEHP exposure is often higher in the Taiwanese population than other countries such as in Germany or the US [15,16].H. pyloriinfection SNX-2112 occurs in approximately 50% of the world’s population. The Taiwanese population has as a 54.4% antibody seropositivity againstH. pylori[17], which is higher than theH. pyloriseropositivity in other countries, such as Ireland [18]. Taken together, these data demonstrate that the high exposure rate of DEHP and high infection rate ofH. pyloriin the Taiwanese people, as well as with the rest of the world, are likely an important health concern; however, the effect of DEHP andH. pyloricoexposure on gastric epithelial cells is not well understood. For this reason, the effect of DEHP andH. pyloricoexposure on gastric epithelial cell apoptosis, as an indicator of reduced epithelial cell integrity, was investigated in this study. == 2. Materials HSPB1 and Methods == == 2.1. Cell Culture == A human gastric epithelial cell line, AGS (gastric adenocarcinoma. BCRC 60102), was purchased from the Cell Bank of the Taiwan National Health Research Institute and was grown in RPMI 1640 medium supplemented with 10% fetal bovine serum, 100 U/mL penicillin, and 100g/mL streptomycin or 0.1% gentamicin (Hyclone, Logan, UT, USA). AGS cells were seeded at densities of 2~2.5 105/35-mm culture dish or 5~5.5 105/25 T flask, incubated for 24 hr, and switched to culture medium containing 0~80M DEHP (CAS number: 117-81-7, Sigma-Aldrich, St. Louis, MO, USA). DEHP has limited solubility in water; a stock solution of DEHP was prepared in DMSO and subsequently diluted to various concentrations with cell culture medium. The final concentration of DMSO in culture medium was approximately 1% and had no significant effect on cell viability. All cultures were grown in a humidified incubator at 37C and in an atmosphere of 95% air-5% CO2. == 2.2.H. pyloriCulture == Due to the role of cytotoxin associated gene A (CagA) and vacuolating cytotoxin A (VacA) genes, genes commonly associated withH. pyloriassociated gastric cell apoptosis [19], the CagA/VacA positiveH. pyloristrain ATCC 43054, purchased.