Effect of lipopolysaccharide on lactose metabolism of dairy cow mammary epithelial cells and its mechanism
10.13200/j.cnki.cjb.004018
- VernacularTitle:脂多糖对奶牛乳腺上皮细胞乳糖代谢的影响及其作用机制
- Author:
LIU Xiuzhi
- Publication Type:Journal Article
- Keywords:
Dairy cows;
Mammary epithelial cells;
Lipopolysaccharide(LPS);
Lactose;
Glucose;
Glycolysis
- From:
Chinese Journal of Biologicals
2025;38(03):291-296+311
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the effect of lipopolysaccharide(LPS) on the lactose metabolism in mammary epithelial cells of dairy cows(MAC-T) and its mechanism,so as to provide a new idea for the selection of a more reasonable immune metabolism regulation scheme to ensure the health of mammary glands of dairy cows.Methods MAC-T cells were treated with 10 μg/mL LPS for 0,3,6,12 and 24 h,which was detected for the activities of glycolytic enzymes(hexokinase,phosphofructokinase,pyruvate kinase) and the contents of lactic acid,glucose and lactose by ultraviolet light spectrophotometry,for the expression and phosphorylation of hypoxia-inducible factor-1α(FIF-1α) and protein kinase B(also known as AKT) by Western blot and for the transcription levels of HIF-1α,AKT and glucose transporter 1(GLUT1) by fluorescence quantitative RT-PCR. Results Compared with 0 h,the activities of hexokinase and phosphofructokinase reached the peak at3 h(F=4.197 and 6.941,respectively,each P <0.01),and then decreased gradually;The hexoki-nase activity decreased significantly at 24 h(F=4.987,P <0.01) while the phosphofructokinase activity maintained at a relatively high level within24 h;The activity of pyruvate kinase increased significantly in the first 6 h,then increased very significantly,and increased to 27 times of that at 0 h after treatment for 24 h(F=26.95,P <0.001).During 24 h treatment with LPS,the lactose content decreased significantly;Glucose content increased significantly at 3 h(t=4.294,P <0.001),then showed a significant downward trend,and decreased significantly at 24 h(t=5.218,P <0.001);The lactic acid content increased significantly at 12 and 24 h.The expression levels of HIF-1α mRNA and protein increased significantly 6 h after LPS treatment(F=5.355 and 5.466,respectively,P<0.001),and then decreased gradually;The expression level of total AKT mRNA and protein and p-AKT(Ser473) protein all increased significantly 24 h after LPS treatment(F=6.207,6.368 and 6.253,respectively,each P <0.01);The mRNA transcription level of GLUT1 increased significantly at 3,6 and 12 h after LPS stimulation(F=6.549,5.821 and 5.553,respectively,each P <0.01).Conclusion LPS treatment results in increased glucose uptake by MAC-T cells,and the glucose intake has shifted from mostly for lactose synthesis to mostly for glycolytic metabolism and inflammatory response,leading to significant decrease of lactose synthesis in cells.
