The Mechanism Of Taurine Attenuated Inflamatory Injury Induced By Streptococcus Uberis

In this study,we used mouse mammary epithelial cells line(EpH4-Ev),mouse immunocyte(T lymphocyte,B lymphocyte)and Streptococcus uberis 0140)(S.uberis 0140J)as the research objects.Then,we utilized S.uberis 0140J to infect EpH4-Ev and mouse immunocyte and investigated the inflammatory injury;on this basis,to reveal the protective effect of taurine on defense mechanism in EpH4-Ev and defensive cells.This research lucubrated and clarified the mechanism of taurine to attenuate inflammatory injury of mouse mammary epithelial cells induced by Streptococcus uberis.The results were as follows:1 Taurine attenuates Streptococcus uberis-induced inflammation changes in mouse mammary epithelial cellsIn order to investigate the cell inflammation changes after EpH4-Ev infected S.uberis and the role of taurine attenuation on inflammation changes.In this study,EpH4-Ev and S.uberis 0140J were chosen as the research objects.Firstly,we detected the cell inflammatory changes after EpH4-Ev incubation with S.uberis 0140J and on this basis to explore the protective effect of taurine on adhesion of S.uberis and cell inflammatory injury.The results showed that S.uberis 0140)could adhere to EpH4-Ev and taurine treatment could reduced the effect of adhension.However,no statistical significance was observed between the different taurine treatment groups.Two hours after EpH4-Ev infected with S.uberis 0140J,the expression levels of TNF-a,IL-lp and IL-6 mRNA and NAGase activity in cell culture supernatants were increased significantly(P<0.01)and the expression level of LF mRNA increased significantly(P<0.01)at 4 hours post-incubation.Pre-treated mouse mammary epithelial cells with 15 mmol/L and 45 mmol/L taurine significantly reduced the expression levels of TNF-a,IL-1β and 1L-6(P<0.01),and 5 mmol/L,15 mmol/L taurine significantly decreased the activity of NAGase(P<0.01).The results showed that,taurine could attenuate the inflammation changes of mouse mammary epithelial cells induced by the S.uberis 0140J.This effect may be related to the reduction of the adhesion of S.uberis 0140J to EpH4-Ev.2 The role of Ca2+ mediated signaling pathways in the effect of taurine againstStreptococcus uberis infectionIn order to investigate the role of Ca2+ mediated signaling pathway in taurine against Streptococcus uberis infection,this research took the EpH4-Ev and S.uberis 0140)as the research objects.Firstly,we detected the expression level of TLR-2 and detected intracellular Ca2+ concentrations by flow cytometry after S.uberis 0140)incubated with EpH4-Ev.Secondly,detected the Ca2+ related protein contents and activities of nuclear transcription factor by enzyme linked immuno sorbent assay and electrophoretic mobility shift assay.Finally,detected the contents of downstream inflammatory factors by protein chips;on these basis to explore the effect of taurine on inflammatory pathway mediated by Ca2+.The results showed that:the expression level of TLR-2 was increased significantly(P<0.01)after EpH4-Ev infected with S.uberis 0140J,and pre-treated with taurine significantly reduced the expression level of TLR-2.The infection of S.uberis 0140J caused intracellular Ca2+ concentrations increased significantly(P<0.01)and pre-treated with taurine significantly decreased the concentrations of Ca2+ After S.uberis 0140J infected EpH4-Ev,the contents of PKC-α and PLC-γ1 protein increased significantly(P<0.01)and pre-treated with taurine significantly decreased(P<0.05).The activities of nuclear transcription factor NF-κB and NFAT levels increased significantly(P<0.01)after S.uberis 0140)infected EpH4-Ev,and pre-treated with taurine significantly decreased the activities of nuclear transcription factor NF-κB and NFAT levels(P<0.05).After S.uberis 0140J infected EpH4-Ev,the fluorescence intensities of G-CSF,IL-6 and MCP-1 increased significantly(P<0.01)in supernatant;the fluorescence intensities of IL-2,TNF-α,IL-1β,KC,FasL,LIX increased significantly(P<0.05),but IL-15.Furthermore,pre-treated with taurine significantly decreased the fluorescence intensity of IL-6(P<0.01);and the fluorescence intensities of IL-2,TNF-α,IL-1β,KC,MCP-1 significantly decreased(P<0.05).The results showed that,taurine could reduce the concentrations of intracellular Ca2+ caused by S.uberis 0140J infected EpH4-Ev,and decreased the contents of Ca2+related protein,the activities of nuclear transcription factor and the fluorescence intensities of inflammatory factors.So the mechanisms of TLR-2 and Ca2+ mediated inflammatory pathways closely related to the effect of taurine against Streptococcus uberis infection.3 The function of TLR-2 on taurine affected changes in Ca2-induced by Streptococcus uberis infection in mice immunocytesLn order to investigate the effects of taurine on changes of Ca2+ induced byStreptococcus uberisinfection in mouse immunocytes.In this study,the T lymphocytes and neutrophils of normal B6 and TLR-2 gene deleted mice and S.uberis 0140)were chosen as the research objects.The intracellular Ca2+ concentrations were detected by flow cytometry after S.uberis 0140)incubated with T lymphocytes and neutrophils.The results showed that,in normal B6 mice,infection of S.uberis 0140)could cause the concentrations of Ca2+increased significantly(P<0.01)both in T lymphocytes and neutrophils.Pre-treated with taurine significantly reduced the concentrations of Ca2+ in T lymphocytes(P<0.01)5 but in neutrophils.In TLR-2 gene deleted mice,infection of S.uberis 0140)caused the concentrations of Ca2+ increased significantly(P<0.05)in T lymphocytes and taurine pre-treated reduced them significantly(P<0.01).This was not find in neutrophils.The results showed that,taurine could reduce the concentrations of Ca2+ both in normal B6 and TLR-2 gene deleted mice immunocytes after infected by S.uberis 0140J.Compared with normal B6 mice,ihe concentrations of Ca2-in TLR-2 gene deleted mice was lower.This indicated that the elevation of concentrations of Ca2+ were related to TLR-2.