The aim of this study is to reveal the regulation mechanism of the effect of Semen vaccariae and Taraxacu mogono on the cell-cell adhersion molecule, E-cadherin and b-catenin on the proliferation role and secretion function of bovine mammary epithelial cells cultured in vitro. Firstly, the epithelial character of bovine mammary epithelial cells was authenticated using immunofluorescence, then the cell grow curve was observed and investigated after S. vaccariae and T. mogono treatment. On the effect of S. vaccariae and T. mogono, cell adhesion molecules E-cadherin, b-catenin and CycinD1 mRNA and protein were detected by qRT-PCR and Western blotting, respectively. The results showed that the cellular keratin 18 expressed positively and proliferated vigorously after S. vaccariae and T. mogono treament. The mRNA and protein levels of E-cadherin and CycinD1 were remarkably higher (P<0.05) in 36 h after S. vaccariae and T. mogono treatment. The cell proliferation at 36 h was increased significantly (P<0.05). In conclusion, S. vaccariae and T. mogono have a positive impact on the cell proliferation and an effect on the adhesion molecules E-cadherin, b-catenin and CycinD1 in the Wnt signaling pathway.

Mitosis of mammary epithelial cell is foundation of mammal lactation. We developed a strategy of combined application of generation of longer cDNA fragments from the serial analysis of gene expression (SAGE) tags for gene identification (GLGI) to screen and identify genes influencing lactating ability of mammary epithelial cell in dairy goat. GLGI as a new tag identification technique was brought about with SAGE. Bzw2 was found as a candidate gene related to lactation by screening Long-SAGE library of mammary gland in dairy goat. Bzw2 cDNA was synthesized by switching mechanism at 5´-end of RNA transcript (SMART) technology. The mRNA level of Bzw2 was relatively higher in early lactation than in other development stages of mammary gland. The proliferation of mammary epithelial cell was inhibited by transfecting specific shRNA of Bzw2. The mRNA levels of Stat5, Csn2 and Prlr were also down-regulated, suggesting the lactating ability of mammary epithelial cell was attenuated after Bzw2 RNAi. The reduction of mammary epithelial cell growth and lactation by Bzw2 RNAi was rescued through over-expression of Bzw2. These results revealed that Bzw2 might play an important role in lactation though the molecular mechanism was still unclear.

In previous experiment, we isolated a compound dibutyl phthalate (DBP) from Vaccaria segetalis which had galactopoieticfunction on mammary gland epithelial cells of dairy cow (DCMECs). In this experiment, we ascertained the metabolicregulation function of DBP on DCMECs. Many genes related to lactation including Stat5, AMPK, â-casein, Glut1, SREBP-1,PEPCK, and ACC were detected by real-time PCR. Furthermore, Stat5 and AMPK were detected by Western blot andimmunofluorescence co-localization, respectively. The results showed that DBP stimulates the expression of Stat5 andp-Stat5, thus activates Stat5 cell signal transduction pathway and stimulates â-casein synthesis. DBP also raises theactivities of Glut1 and AMPK to stimulate glucose uptake and glycometabolism and activates the expression of AMPKdownstream target genes PEPCK and ACC and expression of SREBP-1 to stimulate milk fat synthesis. In addition, theactivities of HK, G-6-PDH, ICDH, ATPase, and energy charges were stimulated by DBP to increase the energy metabolismlevel of DCMECs. The results showed DBP stimulates energy metabolism related to galactopoietic function in DCMECs.