Taurine Resisted The Disfunction Of Mouse Mammary Epithelial Cells Caused Bylps

In this study, primary culture of mouse mammary epithelial cells was first established. The immuno defense of mammary epithelial cells and the damage induced by LPS on mammary epithelial cells were evaluated by co-incubation with LPS. On the base of these, the resistances of taurine on LPS-induced disfunction to mouse mammary epithelial cells were observed.1Establishment and characterization of primary mouse mammary epithelial cellsNormal mouse mammary tissue was taken, and the tissue was digested by collagenase type Ⅰ and Hyaluronidase. The basic medium is DMEM/F12, and10%fetal bovine serum (FBS), insulin(5μg/mL), EGF(10ng/mL), hydrocortisone(1μg/mL), penicillin(100IU/mL) and streptomycin(100IU/mL) were added. The major morphology of epithelial cells appear to be characteristic polygon and cobblestone. The western blot and immunofluorescence showed that the cultured cell is mammary epithelial cell, and it has a function that secretes β-casein. Our results indicate that the mouse mammary epithelial cell still forms functional secretory structures in vitro.2The effect of LPS on mouse mammary epithelial cellsCultured primary mouse mammary epithelial cells were equilibrated to culture conditions for24h. Cells were then stimulated with0μg、5μg、10μg or20μg of LPS per mL for24h before supernatants and cells were collected. The resulted demonstrated that5μg/mL、10μg/mL、20μg/mL LPS dramatically enhanced the activity of N-Acety1-β-D-glucosaminidase (NAGase), the concentrations of nitric oxide(NO) and the levels of mRNA expression of tumor necrosis factor-α (TNF-α), interleukin-1β(IL-1β), interleukin-6(IL-6)and LF(P<0.01).10μg/mL、20μg/mL LPS significantly increased the concentration of tumor necrosis factor-α (TNF-α), interleukin-1β(IL-1β)and interleukin-8(IL-8)(P＜0.05). And there was a significant decrease in the secretion of β-casein in the presence of20μg/mL LPS(P<0.05). Furthermore, cell survival was significantly inhibited by treatment with20μg/mL LPS, however,5μg/ml、10μg/mL LPS had no pronounced effect on cell survival. The result showed that10μg/mL LPS induced the disfunction to mouse mammary epithelial cells without adversely affecting cell survival.3Taurine resisted the disfunction of mouse mammary epithelial cells caused by LPSMouse mammary epithelial cells were pre-cultured on culture flask for3days, before being treated with taurine for3h followed by LPS(10μg/mL)for24h. Supernatants and cells were left. The resulted demonstrated that the activity of N-Acetyl-β-D-glucosaminidase (NAGase)、the concentrations of nitric oxide(NO), the levels of mRNA expression and the concentrations of tumor necrosis factor-a (TNF-a)、 interleukin-1β(IL-1β)and interleukin-6(IL-6)were significantly increased in LPS-treated mammary epithelial cells. The increased activity of N-Acetyl-β-D-glucosaminidase (NAGase)and the concentrations of nitric oxide(NO)were marked reduced by5mmol/L,15mmol/L,45mmol/L taurine. And significant decrease was observed in the expression and the concentrations of TNF-α、IL-1β、IL-6in both15mmol/L and45mmol/L taurine. Our in vitro study showed that Adding taurine to the medium significantly inhibited LPS-induced the release of inflammatory factors from the mammary epithelial cells, thereby providing a novel explanation for the resisitant potential proposed for taurine in the prevention of LPS-induced disfunction in mammary epithelial cells.