| The aim of this study was to investigate the protective effect of Chlorogenic acid on bovine mammary epithelial cells infected with S.aureus and the effect of Chlorogenic acid on bovine blood neutrophil function and gene expression in vitro.Experiment one:Chlorogenic acid inhibits S.aureus growth and alters its interactions with bovine mammary epithelial cellsGrowth inhibition was examined by adding 0,10,20 and 30 μg/mL Chlorogenic acid to S.aureus in nutrient broth.The results show that before 9 h Chlorogenic acid have no effect on growth of S.aureus at all concentrations,30 μg/mL Chlorogenic acid can inhibit the growth of S.aureus at 9,12 h(P<0.05).10 pg/mL Chlorogenic acid can inhibit the growth of S.aureus at 24 h(P<0.05),and 20,30 μg/mL Chlorogenic acid also can inhibit the growth of S.aureus at 24h(P<0.01).It was also observed that Chlorogenic acid had no effect on preformed biofilms except at a concentration of 20 μg/mL,in which a significant reduction in the measured absorbance was noted(P<0.05).Chlorogenic acid have no cytotoxic effect on bovine mammary epithelial cells at concentrations of 10,20,30 μg/mL,and 20 μg/mL Chlorogenic acid can elevate the viability of bovine mammary epithelial cells infected with S.aureus(P<0.05).Chlorogenic acid had no effect on association of S.aureus to bovine mammary epithelial cells at all concentrations tested,but,Chlorogenic acid was shown to inhibit invasion of S.aureus specifically at concentration of 30 μg/mL(P<0.05).30 μg/mL Chlorogenic acid can reduce the production of Reactive oxygen species(ROS)of bovine mammary epithelial cells infected with S.aureus(P<0.05).Experiment two:Modulation of the inflammatory response of bovine mammary epithelial cells by Chlorogenic acid during Staphylococcus aureus infectionS.aureus strongly induced the mRNA expression of TNF-α,IL-10,IL-6,IL-8,TLR-2 and MyD88.30 μg/mL Chlorogenic acid inhibited the bacterial-induced expression of IL-1β,IL-6,IL-8,TLR-2(P<0.01),but,have no influence on TNF-α,MyD88 mRNA expression.The present study showed that the phosphorylation levels of p38 and JNK were greatly reduced in Chlorogenic acid-treated groups compared with the S.aureus group,have no influence on phosphorylation levels of ERK.Experiment three:The effect of Chlorogenic acid on bovine blood neutrophil function and gene expressionThe objective of this study was to investigate the effect of Chlorogenic acid on bovine blood PMNL chemotaxis and phagocytosis capabilities and sterilization function and the expression of genes involved in inflammatory response in vitro.The results show that Chlorogenic acid have no cytotoxic effect on bovine mammary epithelial cells at concentrations of 10,20,30 μg/mL.10,20,30 μg/mL Chlorogenic acid have no influence on PMNL chemotactic capability.30 μg/mL Chlorogenic acid increased PMNL phagocytosis capability(P<0.01).20 μg/mL Chlorogenic acid elevated the sterilization function of PMNL(P<0.05).The expression of genes involved in the proinflammatory response IL-1β,TLR-2 was primarily downregulated;however,TGF-β,IL-8 production was not altered by Chlorogenic acid when compared with controls. |
PDF Full Text Request