Correlation Analysisbetween P38 MAPK Signaling Pathway Associcated Molecule And Bovine Mastitis

The study foucus on the molecules pathogenesis of bovine mastitis.Milk,blood and tissue samples were collected to measure the protein and mRNA expressions of p38 MAPK and p38 MAPK associated molecules.The study provided evidence that p38 played an important role during bovine mastitis.Section one:To find out the relationship between mastitis and PRR,such as LBP and CD 14,41 Chinese Hesitant cows were chosen,including 20 healthy cows and 21 cows with clinical mastitis.Blood and milk samples were collected to investigate the association among LBP,CD 14,TNF-α and IL-1β protein expressions by ELISA.Somatic cell count(SCC)of milk showed that SCC of healthy cows were below 200000 cells/ml and SCC of cows with clinical mastitis were higher than 50000 cells/ml.Limulus Amoebocyte Lysate kits were used to measure concentrations of LPS in blood.Levels of LPS were increased in milk and blood samples in the clinical mastitis group.Moreover,the protein expression of the LBP,CD 14,TNF-α and IL-1β were increased in the clinical mastitis group than the healthy group.Positive correlation showed among LBP,CD 14,TNF-α and IL-1β in milk and that in blood.The results demonstrate that LBP,CD 14,TNF-α and IL-1β are involved to protect the udders from mastitis in a synergism way.Section two:The p38 mitogen-activated protein kinase(MAPK)singaling pathway is one of the four major signaling pathway in eukaryocyte.It regulates a wide range of inflammatory responses,and it can modulate the expression of TNF-α and IL-1β.In order to understand the role of p38 MAPK in bovine mastitis,we selected 6 hesitant cows from section one.Blood,milk and tissue samples were collected to measure the protein and mRNA expressions of p38 and p38 associated molucules.In our study,HE was used for the histological observation.q-PCR,ELISA and western blot were used to measure the expressions of p38 and p38 associated proteins,LBP,CD14,TLR4,TNF-α and IL-1β.The q-PCR showed that the mRNA expressions ofLBP,CD14,p38,IL-1β and TNF-α increased significantly in mastitis group than the healthy group(P<0.05).ELISA results indicated that LBP,CD14,TNF-α and IL-1β increased significant in mastitis group(P<0.05)though the difference of LBP was not significant between serum samples of the two groups.The western blot results of TLR4,p38 and p-p38 indicated that those protein expressions increased significantly(P<0.05)in clinical mastitis cows than healthy cows.Taken together,our study provide new evidence for better understanding the differential expression and machnisms of the p38 MAPK signaling pathway in Chinese Holstein cattle with mastitis.