ABSTRACT
Peroxisome proliferator-activated receptors (PPARs) and liver X receptor alpha are ligand-activated transcription factors that belong to nuclear receptors superfamily and are involved in the regulation of lipid metabolism. PPAR, especially PPAR-alpha, PPAR-gamma agonists and liver X receptor alpha agonists can regulate the expression or biosynthesis of some factors involved in the formation and function of HDL, such as apolipoprotein (apo) A-I and ATP binding cassette transporter A1 (ABCA1). It is well known that HDL plays an important role in the treatment of hyperlipidemia as the carrier of reverse cholesterol transport. In the present study, the anti-hyperlipidemic properties of CM108, a derivative of flavone, 9-Hydroxy-2-mercapto-6-phenyl-2-thioxo-1,3,5-trioxa-2lambda(5)-phospha-cyclopenta[b]naphthalen-8-one, were studied. Through the transactivation assays of in vitro study, it was discovered that CM108 could activate PPAR-alpha PPAR-gamma and liver X receptor alpha at 40-150 microg/ml, which subsequently resulted in activating ABCA1 promoter and enhancing apoA-I and apoA-II production, whereas reducing apoC-III production significantly. Furthermore, after in vivo study that the hyperlipidemic rats were treated with CM108 for 4 weeks, a significant increase was found in HDL cholesterol levels (26.7%, P<0.05) and a significant decrease was also noticed in triglyceride levels (26.3%, P<0.01) at 100 mg/kg CM108 group compared with that of control animals. Meanwhile, the atherogenicity index, represented by total cholesterol/HDL ratio, was significantly reduced (P<0.01). In conclusion, CM108 can effectively elevate HDL levels and lower triglyceride levels in hyperlipidemic rats maybe by regulating a series of genes, receptors and proteins related to HDL.
