10 research outputs found

    CIDEA Regulates De Novo Fatty Acid Synthesis in Bovine Mammary Epithelial Cells by Targeting the AMPK/PPAR╬│ Axis and Regulating SREBP1

    No full text
    Cell-death-inducing DNA fragmentation factor-╬▒-like effector A (CIDEA) is a lipid-droplet-associated protein that helps to promote lipid metabolism in adipocytes of mice and humans. However, studies on the regulatory mechanism of CIDEA on lipid metabolism in the mammary glands of dairy cows are rare. Therefore, the role of CIDEA in bovine mammary epithelial cells (bMECs) was investigated in this study. The CIDEA expression levels in the mammary glands of high-fat-milk-producing cows were significantly higher compared to those in low-fat-milk-producing cows. Results of in vitro studies in bMECs showed that the inhibition of CIDEA inhibited the expression of fatty acid synthesis-related genes and triglyceride (TAG) synthesis-related genes. Conversely, the overexpression of CIDEA leads to an increase in the content of TAG and fatty acid. The results of mechanistic studies indicated that the overexpression of CIDEA inhibits AMP-activated protein kinase (AMPK) activity, which enhances the expression of peroxisome proliferator-activated receptor-╬│ (PPAR╬│) and consequently increases the TAG content. Furthermore, the overexpression of CIDEA promoted the nuclear translocation of sterol regulatory element-binding protein 1 (SREBP1). Therefore, a theoretical framework is provided by this study for the regulation of lipid metabolism in dairy cows by means of nutrition and the hormone targeting of CIDEA

    Acetic acid activates the AMP-activated protein kinase signaling pathway to regulate lipid metabolism in bovine hepatocytes.

    Get PDF
    <p>Acetic acid is metabolized to acetyl-CoA with consumption of ATP in bovine hepatocytes, resulting in a significant elevation of the AMP/ATP ratio and the phosphorylation and activation of AMPK╬▒. Activated AMPK╬▒ increases the expression and transcriptional activity of PPAR╬▒, thereby increasing the expression of lipolytic genes, including ACO, CPT1, CPT2, and L-FABP. AMPK╬▒ activation inhibits the expression and transcriptional activity of SREBP-1c and ChREBP, thereby reducing the expression of lipogenic genes, including ACC1, FAS, and SCD-1. In addition, activated AMPK╬▒ directly phosphorylates and inhibits ACC1. Consequently, acetic acid increases lipolysis and reduces lipid synthesis in bovine hepatocytes.</p

    Acetic acid activates the AMPK╬▒ signaling pathway.

    No full text
    <p>Hepatocytes were treated with acetate and BML-275 and were divided into a control group (0 mM acetate), a low-dose acetate treatment group (1.8 mM acetate), a medium-dose acetate treatment group (3.6 mM acetate), a high-dose acetate treatment group (7.2 mM acetate), a BML-275 group (10 ╬╝M BML-275), and a BML-275+acetate group (10 ╬╝M BML-275+3.6 mM acetate). Acetate (sodium acetate) was used in the form of neutralized acetic acid to avoid changing the pH of the medium. A: AMP content. B: ATP content. C: AMP/ATP ratio. D: Western blotting results for SIRT1, LKB1, p-AMPK╬▒, and AMPK╬▒. E: The protein levels of SIRT1. F: The protein levels of LKB1. G: The phosphorylation level of AMPK╬▒ (p-AMPK╬▒/AMPK╬▒). H: AMPK╬▒ activity. * <i>p</i><0.05, ** <i>p</i><0.01 versus the control group.</p

    Transcriptional activity of PPAR╬▒, SREBP-1c, and ChREBP in hepatocytes.

    No full text
    <p>Hepatocytes were treated with acetate and BML-275 and divided into a control group (0 mM acetate), a low-dose acetate treatment group (1.8 mM acetate), a medium-dose acetate treatment group (3.6 mM acetate), a high-dose acetate treatment group (7.2 mM acetate), a BML-275 group (10 ╬╝M BML-275), and a BML-275+acetate group (10 ╬╝M BML-275+3.6 mM acetate). Acetate (sodium acetate) was used in the form of neutralized acetic acid to avoid changing the pH of the medium. A and B: EMSA results for PPAR╬▒. C and D: EMSA results for SREBP-1c. E and F: EMSA results for ChREBP. * <i>p</i><0.05, ** <i>p</i><0.01 versus the control group.</p

    The phosphorylation level and enzyme activity of ACC1.

    No full text
    <p>Hepatocytes were treated with acetate and BML-275 and divided into a control group (0 mM acetate), a low-dose acetate treatment group (1.8 mM acetate), a medium-dose acetate treatment group (3.6 mM acetate), a high-dose acetate treatment group (7.2 mM acetate), a BML-275 group (10 ╬╝M BML-275), and a BML-275+acetate group (10 ╬╝M BML-275+3.6 mM acetate). Acetate (sodium acetate) was used in the form of neutralized acetic acid to avoid changing the pH of the medium. A: Western blotting results for p-ACC1 and ACC1. B: The phosphorylation level of ACC1. C: Enzyme activity of ACC1. * <i>p</i><0.05, ** <i>p</i><0.01 versus the control group.</p

    The mRNA and protein expression levels of PPAR╬▒, SREBP-1c, and ChREBP in the hepatocytes.

    No full text
    <p>Hepatocytes were treated with acetate and BML-275 and divided into a control group (0 mM acetate), a low-dose acetate treatment group (1.8 mM acetate), a medium-dose acetate treatment group (3.6 mM acetate), a high-dose acetate treatment group (7.2 mM acetate), a BML-275 group (10 ╬╝M BML-275), and a BML-275+acetate group (10 ╬╝M BML-275+3.6 mM acetate). Acetate (sodium acetate) was used in the form of neutralized acetic acid to avoid changing the pH of the medium. A: Western blotting results of PPAR╬▒, SREBP-1c, and ChREBP. B and C: mRNA and protein levels of PPAR╬▒. D and E: mRNA and protein levels of SREBP-1c. F and G: mRNA and protein levels of ChREBP. * <i>p</i><0.05, ** <i>p</i><0.01 versus the control group.</p

    The mRNA expression levels of PPAR╬▒, SREBP-1c, and ChREBP target genes in hepatocytes.

    No full text
    <p>Hepatocytes were treated with acetate and BML-275 and divided into a control group (0 mM acetate), a low-dose acetate treatment group (1.8 mM acetate), a medium-dose acetate treatment group (3.6 mM acetate), a high-dose acetate treatment group (7.2 mM acetate), a BML-275 group (10 ╬╝M BML-275), and a BML-275+acetate group (10 ╬╝M BML-275+3.6 mM acetate). Acetate (sodium acetate) was used in the form of neutralized acetic acid to avoid changing the pH of the medium. A-D: mRNA expression levels of ACO, CPT1, L-FABP, and CPT2, respectively. E-G: mRNA expression levels of ACC1, FAS, and SCD-1, respectively. * <i>p</i><0.05, ** <i>p</i><0.01 versus the control group.</p

    Effect of the duration of acetic acid treatment on AMPK╬▒ phosphorylation and activity in hepatocytes.

    No full text
    <p>Hepatocytes were treated with 3.6 mM acetate (neutralized acetic acid) for 0, 1, 3, 6, 10 16, and 24 h. A: Western blotting results of p-AMPK╬▒ and AMPK╬▒. B: The phosphorylation level of AMPK╬▒ (p-AMPK╬▒/AMPK╬▒). C: AMPK╬▒ activity. * <i>p</i><0.05, ** <i>p</i><0.01 versus the control group.</p
    corecore