| First Author | Stec DE | Year | 2019 |
| Journal | Am J Physiol Regul Integr Comp Physiol | Volume | 317 |
| Issue | 5 | Pages | R733-R745 |
| PubMed ID | 31483154 | Mgi Jnum | J:282037 |
| Mgi Id | MGI:6370253 | Doi | 10.1152/ajpregu.00153.2019 |
| Citation | Stec DE, et al. (2019) Loss of hepatic PPARalpha promotes inflammation and serum hyperlipidemia in diet-induced obesity. Am J Physiol Regul Integr Comp Physiol 317(5):R733-R745 |
| abstractText | Agonists for PPARalpha are used clinically to reduce triglycerides and improve high-density lipoprotein (HDL) cholesterol levels in patients with hyperlipidemia. Whether the mechanism of PPARalpha activation to lower serum lipids occurs in the liver or other tissues is unknown. To determine the function of hepatic PPARalpha on lipid profiles in diet-induced obese mice, we placed hepatocyte-specific peroxisome proliferator-activated receptor-alpha (PPARalpha) knockout (Ppara(HepKO)) and wild-type (Ppara(fl/fl)) mice on high-fat diet (HFD) or normal fat diet (NFD) for 12 wk. There was no significant difference in weight gain, percent body fat mass, or percent body lean mass between the groups of mice in response to HFD or NFD. Interestingly, the Ppara(HepKO) mice on HFD had worsened hepatic inflammation and a significant shift in the proinflammatory M1 macrophage population. These changes were associated with higher hepatic fat mass and decreased hepatic lean mass in the Pparalpha(HepKO) on HFD but not in NFD as measured by Oil Red O and noninvasive EchoMRI analysis (31.1 +/- 2.8 vs. 20.2 +/- 1.5, 66.6 +/- 2.5 vs. 76.4 +/- 1.5%, P < 0.05). We did find that this was related to significantly reduced peroxisomal gene function and lower plasma beta-hydroxybutyrate in the Ppara(HepKO) on HFD, indicative of reduced metabolism of fats in the liver. Together, these provoked higher plasma triglyceride and apolipoprotein B100 levels in the Ppara(HepKO) mice compared with Ppara(fl/fl) on HFD. These data indicate that hepatic PPARalpha functions to control inflammation and liver triglyceride accumulation that prevent hyperlipidemia. |
