Antioxidant, Anti-inflammatory and Hypolipidemic Properties of Apple Flavonols

Abstract

Obesity is considered an underlying risk factor for metabolic disease including cardiovascular disease (CVD) and diabetes. The fractions containing flavonols from apple peel were evaluated for their antioxidant, anti-inflammatory, and hypolipidemic properties using in vitro and in vivo experimental model systems. The fractionated polyphenolics from apple peels showed a strong antioxidant property protecting against heat-induced oxidation of polyunsaturated fatty acids present in fish oil. Apple flavonols (AF), eicosapentaenoic acid (EPA) and the isoquercitrin-EPA ester (QE) significantly reduced serum triacylglycerols and elevated the high density lipoprotein (HDL)-cholesterol compared to the high fat control group. C-reactive protein and interleukin-6 were also reduced compared to the high fat control group and inflammation induced by lipopolysaccharides. Serum adiponectin and interferon-? concentrations were significantly altered by QE treatment. Overall, AF and QE exhibited anti-inflammatory and hypolipidemic effects under in vivo conditions. These beneficial physiological properties and mode of action of AF and QE need to be further investigated.