Journal Article

Identification of Novel Regulatory Cholesterol Metabolite, 5-Cholesten, 3β,25-Diol, Disulfate

Kakiyama, Genta, Ning, Yanxia, Min, Hae-Ki, Pandak, William M., Ren, Shunlin, Rodriguez-Agudo, Daniel, Kim, Jin Koung

2014

Overview

Oxysterol sulfation plays an important role in regulation of lipid metabolism and inflammatory responses. In the present study, we report the discovery of a novel regulatory sulfated oxysterol in nuclei of primary rat hepatocytes after overexpression of the gene encoding mitochondrial cholesterol delivery protein (StarD1). Forty-eight hours after infection of the hepatocytes with recombinant StarD1 adenovirus, a water-soluble oxysterol product was isolated and purified by chemical extraction and reverse-phase HPLC. Tandem mass spectrometry analysis identified the oxysterol as 5-cholesten-3β, 25-diol, disulfate (25HCDS), and confirmed the structure by comparing with a chemically synthesized compound. Administration of 25HCDS to human THP-1-derived macrophages or HepG2 cells significantly inhibited cholesterol synthesis and markedly decreased lipid levels in vivo in NAFLD mouse models. RT-PCR showed that 25HCDS significantly decreased SREBP-1/2 activities by suppressing expression of their responding genes, including ACC, FAS, and HMG-CoA reductase. Analysis of lipid profiles in the liver tissues showed that administration of 25HCDS significantly decreased cholesterol, free fatty acids, and triglycerides by 30, 25, and 20%, respectively. The results suggest that 25HCDS inhibits lipid biosynthesis via blocking SREBP signaling. We conclude that 25HCDS is a potent regulator of lipid metabolism and propose its biosynthetic pathway.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Acetyl-CoA Carboxylase - genetics / Acetyl-CoA Carboxylase - metabolism / Adenoviridae - metabolism / Animal models / Animals / Bile / Biology and Life Sciences / Biosynthesis / Cells, Cultured / Chemical extraction / Cholesterol / Cholesterol - analysis / Cholesterol - biosynthesis / Cholesterol - metabolism / Cholesterol Esters - analysis / Cholesterol Esters - chemical synthesis / Cholesterol Esters - pharmacology / Disease Models, Animal / Fatty Acid Synthases - genetics / Fatty Acid Synthases - metabolism / Fatty acids / Female / Gene expression / Hep G2 Cells / Hepatocytes / Hepatocytes - cytology / Hepatocytes - metabolism / High-performance liquid chromatography / Humans / Hydroxycholesterols - analysis / Hydroxycholesterols - chemical synthesis / Hydroxycholesterols - pharmacology / Hydroxymethylglutaryl CoA Reductases - genetics / Hydroxymethylglutaryl CoA Reductases - metabolism / Hydroxymethylglutaryl-CoA reductase / Inflammation / Lipid metabolism / Lipid Metabolism - drug effects / Lipids / Liquid chromatography / Liver / Macrophages / Mass spectrometry / Mass spectroscopy / Medicine and Health Sciences / Metabolism / Metabolites / Mice, Inbred C57BL / Mitochondria / Non-alcoholic Fatty Liver Disease - metabolism / Non-alcoholic Fatty Liver Disease - pathology / Nuclei / Polymerase chain reaction / Rats / Rodents / Signal Transduction - drug effects / Signaling / Sterol Regulatory Element Binding Protein 1 - metabolism / Sterol Regulatory Element Binding Protein 2 - metabolism / Sterol regulatory element-binding protein / Sulfation / Tissues / Triglycerides / Viral Proteins - genetics / Viral Proteins - metabolism / Water purification