Maize which has very high omega-6 fatty acid content has been used as a main feed grain for Hanwoo beef production to increase marbling, and thus omega-6 to omega-3 fatty acids ratio in Hanwoo beef is Show more
Maize which has very high omega-6 fatty acid content has been used as a main feed grain for Hanwoo beef production to increase marbling, and thus omega-6 to omega-3 fatty acids ratio in Hanwoo beef is expected to be biased. To elucidate the current status of omega fatty acids ratio in Hanwoo beef, fatty acid profiles of neutral lipid and phospholipid fraction were analyzed separately using 55 Hanwoo steers' Show less
Retinoid-related orphan receptor (ROR)Ī±4 is the major RORĪ± isoform expressed in adipose tissues and liver. In this study we demonstrate that RORĪ±-deficient staggerer mice (RORĪ±(sg/sg)) fed with a high Show more
Retinoid-related orphan receptor (ROR)Ī±4 is the major RORĪ± isoform expressed in adipose tissues and liver. In this study we demonstrate that RORĪ±-deficient staggerer mice (RORĪ±(sg/sg)) fed with a high-fat diet (HFD) exhibited reduced adiposity and hepatic triglyceride levels compared with wild-type (WT) littermates and were resistant to the development of hepatic steatosis, adipose-associated inflammation, and insulin resistance. Gene expression profiling showed that many genes involved in triglyceride synthesis and storage, including Cidec, Cidea, and Mogat1, were expressed at much lower levels in liver of RORĪ±(sg/sg) mice. In contrast, overexpression of RORĪ± in mouse hepatoma Hepa1-6 cells significantly increased the expression of genes that were repressed in RORĪ±(sg/sg) liver, including Sult1b1, Adfp, Cidea, and ApoA4. ChIP and promoter analysis suggested that several of these genes were regulated directly by RORĪ±. In addition to reduced lipid accumulation, inflammation was greatly diminished in white adipose tissue (WAT) of RORĪ±(sg/sg) mice fed with an HFD. The infiltration of macrophages and the expression of many immune response and proinflammatory genes, including those encoding various chemo/cytokines, Toll-like receptors, and TNF signaling proteins, were significantly reduced in RORĪ±(sg/sg) WAT. Moreover, RORĪ±(sg/sg) mice fed with an HFD were protected from the development of insulin resistance. RORĪ±(sg/sg) mice consumed more oxygen and produced more carbon dioxide, suggesting increased energy expenditure in this genotype. Our study indicates that RORĪ± plays a critical role in the regulation of several aspects of metabolic syndrome. Therefore, RORĪ± may provide a novel therapeutic target in the management of obesity and associated metabolic diseases. Show less