In Vitro Antioxidant Properties of Equisetum arvense and Its Effects on Serum Lipid Levels in Mice Fed a High-Fat Diet

Abstract

This study analyzed the antioxidant properties of Equisetum arvense and its effects on serum factor levels in mice fed a high-fat diet. The aim was to establish a new effective resource for biologically active materials. E. arvense stem and root extracts were obtained using deionized water at <TEX>$95^{\circ}C$</TEX>, and 70.5% ethanol at <TEX>$85^{\circ}C$</TEX>. These extracts were used to analyze the total phenolic compounds and antioxidant (ABTS, DDPH, and FRAP) activities. The effects of prepared ground samples were evaluated by feeding them to mice. E. arvense extracts showed strong antioxidant effects. The caffeic acid content was highest in the 70.5% ethanol extract of the vegetative stem, as determined by high-performance liquid chromatography. The blood concentrations of insulin and leptin were significantly lower in mice fed a high-fat diet supplemented with extracts of the root, reproductive stem, and vegetative stem of E. arvense than in mice fed only a high-fat diet. These results suggest that the polyphenolic compounds in E. arvense extracts exert various antioxidant effects. The stems and root of E. arvense can lower the blood levels of insulin and leptin, even after consumption of a high-fat diet.