title: 14-3-3γ regulates cell viability and milk fat synthesis in lipopolysaccharide-induced dairy cow mammary epithelial cells.
abstract: Our previous study demonstrated that 14-3-3γ overexpression was able to inhibit the production of lipopolysaccharide (LPS)-induced cytokines in dairy cow mammary epithelial cells (DCMECs) by inhibiting the activation of nuclear factor-κB (NF-κB) signaling pathways. However, the association between 14-3-3γ overexpression and milk fat synthesis in LPS-induced DCMECs remains unclear. Therefore, the present study investigated the effect of 14-3-3γ on cell viability and milk fat synthesis in LPS-induced DCMECs. The results of the MTT assay and lactate dehydrogenase activity assay demonstrated that 14-3-3γ overexpression was able to attenuate LPS-induced cytotoxicity in DCMECs, and increase the viability of the cells. In addition, the results of reverse transcription-quantitative polymerase chain reaction suggested that mRNA expression levels of genes associated with milk fat synthesis, including sterol regulatory element binding protein (SREBP1), peroxisome proliferator-activated receptor-γ (PPARG), cluster of differentiation 36, acetyl-coA carboxylase (ACC), fatty acid synthase (FAS) and fatty acid binding protein-3, were significantly upregulated in cells overexpressing the 14-3-3γ protein. In addition, as compared with the LPS-treated group, the activities of FAS and ACC were significantly increased. Furthermore, western blotting demonstrated that 14-3-3γ overexpression enhanced the protein expression levels of phosphorylated SREBP1 and PPARG. These results suggested that high levels of 14-3-3γ protein were able to attenuate LPS-induced cell damage and promote milk fat synthesis in LPS-induced DCMECs by increasing the cell viability and upregulating the expression levels of transcription factors associated with milk fat synthesis.
authors.affiliation: Key Laboratory of Dairy Science of Education Ministry, Northeast Agricultural University, Harbin, Heilongjiang 150030, P.R. China; College of Pharmacy, Jiamusi University, Jiamusi, Heilongjiang 154007, P.R. China.
authors.forename: Lixin
authors.initials: L
authors.lastname: Liu
authors.affiliation: Key Laboratory of Dairy Science of Education Ministry, Northeast Agricultural University, Harbin, Heilongjiang 150030, P.R. China.
authors.forename: L I
authors.initials: LI
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Dairy Science of Education Ministry, Northeast Agricultural University, Harbin, Heilongjiang 150030, P.R. China.
authors.forename: Y E
authors.initials: YE
authors.lastname: Lin
authors.affiliation: Key Laboratory of Dairy Science of Education Ministry, Northeast Agricultural University, Harbin, Heilongjiang 150030, P.R. China.
authors.forename: Yanjie
authors.initials: Y
authors.lastname: Bian
authors.affiliation: Key Laboratory of Dairy Science of Education Ministry, Northeast Agricultural University, Harbin, Heilongjiang 150030, P.R. China.
authors.forename: Xuejun
authors.initials: X
authors.lastname: Gao
authors.affiliation: Key Laboratory of Dairy Science of Education Ministry, Northeast Agricultural University, Harbin, Heilongjiang 150030, P.R. China.
authors.forename: B O
authors.initials: BO
authors.lastname: Qu
authors.affiliation: Key Laboratory of Dairy Science of Education Ministry, Northeast Agricultural University, Harbin, Heilongjiang 150030, P.R. China.
authors.forename: Qingzhang
authors.initials: Q
authors.lastname: Li
keywords: 14-3-3γ; cell viability; dairy cow mammary epithelial cells; lipopolysaccharide; milk fat synthesis