In conclusion, liver targeting, prolonged half-life, enhanced immunostimulatory functions, and reduced hematological toxicity are properties of IA which make this molecule a promising therapy for patients with viral and/or neoplastic diseases affecting the liver. We thank C. Gomar, I. Echeverría, N. Casares, J. Lasarte, and P. Sarobe for AZD1152HQPA advice and technical support. Additional
Supporting Information may be found in the online version of this article. “
“There is increasing evidence that the retinoic acid receptor–related orphan receptor α (RORα) plays an important role in the regulation of metabolic pathways, particularly of fatty acid and cholesterol metabolism; however, the role of RORα in the regulation of hepatic lipogenesis has not been studied. Here, we report that RORα attenuates hepatic steatosis, probably via activation of the adenosine monophosphate (AMP)-activated protein kinase (AMPK) and repression of the liver X receptor α (LXRα). First, RORα and its activator, cholesterol sulfate (CS), induced phosphorylation of AMPK, which was accompanied by the activation of serine–threonine kinase liver kinase B1 (LKB1). Second, the activation of RORα, either by transient
transfection or CS treatment, decreased the Y-27632 mw TO901317-induced transcriptional expression of LXRα and its downstream target genes, such as the sterol regulatory element binding protein-1 (SREBP-1) and fatty acid synthase. RORα interacted physically with LXRα and inhibited the LXRα response element in the promoter of LXRα, indicating that RORα interrupts the autoregulatory activation loop of LXRα. Third, infection with adenovirus encoding RORα suppressed the lipid accumulation that had been induced by a free-fatty–acid mixture in cultured cells. Furthermore, we observed that the level of expression of the RORα protein was decreased in the liver of mice that were fed a high-fat diet. Restoration of RORα via tail-vein injection of adenovirus
(Ad)-RORα decreased the high-fat-diet–induced hepatic steatosis. Finally, we synthesized thiourea derivatives that activated RORα, thereby inducing activation of AMPK and 上海皓元 repression of LXRα. These compounds decreased hepatic triglyceride levels and lipid droplets in the high-fat-diet–fed mice. Conclusion: We found that RORα induced activation of AMPK and inhibition of the lipogenic function of LXRα, which may be key phenomena that provide the beneficial effects of RORα against hepatic steatosis. (HEPATOLOGY 2012;) An increasing number of populations in the world suffer from fatty liver, which is a disease defined as hepatic fat accumulation greater than 5% of the liver wet weight. The major causes of fatty liver are obesity, diabetes, hyperlipidemia, drugs, and metabolic disorders.