Nanoemulsification of Rice Bran Wax Policosanol Enhances Its Cardio-protective Effects via Modulation of Hepatic Peroxisome Proliferator-activated Receptor gamma in Hyperlipidemic Rats

Policosanol, a mixture of long-chain alcohols found in animal and plant waxes, has several biological effects including lipid-lowering that have been extensively studied. However, its bioavailability is low. To investigate the effect of nanoemulsified rice bran wax policosanol (NPOL) on plasma homocysteine, heart and liver histology in hyperlipidemic rats, high-fat diet containing 2.5% cholesterol was used to induce hyperlipidemia in Sprague Dawley rats. The hyperlipidemic rats were treated with NPOL and rice bran wax policosanol (POL) in comparison with normal diet (ND), high-cholesterol diet (HCD) and simvastatin-treated rats. Plasma homocysteine, heart and liver histology, and hepatic mRNA expression of peroxisome proliferator-activated receptor gamma (PPARG) were evaluated. The NPOL group, similar to the simvastatin group, showed reduced plasma homocysteine, preserved heart and liver histology, and down-regulated hepatic PPARG mRNA in comparison to the control group, and was better than the POL group. The results suggest that the modest effect of NPOL on homocysteine and preservation of heart and liver histology could be through the regulation of PPARG expression on a background of increased assimilation of rice bran wax policosanol.