| First Author | Chen Z | Year | 2008 |
| Journal | Arterioscler Thromb Vasc Biol | Volume | 28 |
| Issue | 10 | Pages | 1738-44 |
| PubMed ID | 18669885 | Mgi Jnum | J:147417 |
| Mgi Id | MGI:3840613 | Doi | 10.1161/ATVBAHA.108.171538 |
| Citation | Chen Z, et al. (2008) Alterations in hepatic metabolism in fld mice reveal a role for lipin 1 in regulating VLDL-triacylglyceride secretion. Arterioscler Thromb Vasc Biol 28(10):1738-44 |
| abstractText | OBJECTIVE: Lipin 1 controls fatty acid metabolism in the nucleus as a transcriptional regulator and in the cytosol as an enzyme catalyzing the penultimate step in phosphoglycerol triacylglyceride (TAG) synthesis. We sought to evaluate the effects of lipin 1 on hepatic TAG synthesis and secretion by gain-of-function and loss-of-function approaches. METHODS AND RESULTS: Rates of TAG synthesis were not impaired in hepatocytes isolated from adult lipin 1-deficient (fld) mice and were actually increased in 14-day-old fld mice. Additionally, compared to littermate controls, VLDL-TAG secretion rates were markedly increased in fld mice of both ages. Lipin 1 overexpression did not alter TAG synthesis rates but significantly suppressed VLDL-TAG secretion. The lipin 1-mediated suppression of VLDL-TAG secretion was linked to the peptide motif mediating its transcriptional-regulatory effects. However, the expression of candidate genes required for VLDL assembly and secretion was unaltered by lipin 1 activation or deficiency. Finally, the hepatic expression of lipin 1 was diminished in obese insulin-resistant mice, whereas adenoviral-mediated overexpression of lipin 1 in liver of these mice inhibits VLDL-TAG secretion and improves hepatic insulin signaling. CONCLUSIONS: Collectively, these studies reveal new and unexpected effects of lipin 1 on hepatic TAG metabolism and obesity-related hepatic insulin resistance. |
