Flaxseed and quercetin improve anti-inflammatory cytokine level and insulin sensitivity in animal model of metabolic syndrome, the fructose-fed rats

Abstract

The purpose of this study is to assess the beneficial effect of quercetin, flaxseed and/or in combination as synergetic in an animal model of metabolic syndrome (MtS), high fructose (HF)-fed rats. Fifty male Sprague–Dawley rats, 3-month old and weighing between 110 and 120g were randomly divided into 2 groups. Rats were given drinking water (−ve control rats) or 10% fructose in drinking water (HF; fructose-fed rats) with standard chow for 8weeks. After 4weeks of fructose feeding, HF-fed rats were further divided into matched 4 subgroups. Different groups of animals (n−10, each group) were administered; 10% HF (5mg/kg, +ve control), flaxseed (F; 50mg/kg), quercetin (Q; 50mg/kg), flaxseed+quercetin, (FQ; 25mg/kg of each), respectively. All ingredients were given orally once daily and subsequent 4weeks. Serum glucose, insulin, lipids profile, leptin, and adiponectin were estimated. After 4weeks of feeding, a significant increase in blood glucose level was observed in HF fed rats compared to normal rats, but this increase was significantly decreased after administration of F, Q and FQ. The raised serum insulin level in HF fed rats was significantly decreased after administration of F and FQ groups. Significantly higher concentrations of triacylglycerols (TG), total cholesterol and low density lipoprotein cholesterol (LDL-C) were observed in HF fed rats and these increases were lower after administration of F, Q and FQ. There was a significant increase in serum high density lipoprotein cholesterol (HDL-C) in the FQ group. The increased serum leptin level was decreased significantly in F, Q and FQ groups. Whereas the reduction of serum adiponectin level in HF fed rats was increased in F, Q and FQ groups. These data suggested that protective effect of flaxseed and quercetin consumption as functional foods could reduce risk for people with decreased insulin sensitivity and increased oxidative stress, such as those with the metabolic syndrome or type 2 diabetes.