No abstract

Bioactive compounds in plant-based food have protective effects against metabolic alterations, including non-alcoholic fatty liver disease (NAFLD). Bean leaves are widely cultivated in the world and are a source of dietary fiber and polyphenols. High fat/high fructose diet animal models promote deleterious effects in adipose and non-adipose tissues (lipotoxicity), leading to obesity and its comorbidities. Short-term supplementation of bean leaves exhibited anti-diabetic, anti-hyperlipidemic, and anti-obesity effects in high-fat/high-fructose diet animal models. This study aimed to evaluate the effect of bean leaves supplementation in the prevention of lipotoxicity in NAFLD and contribute to elucidating the possible mechanism involved for a longer period of time. During thirteen weeks, male Wistar rats (n = 9/group) were fed with: (1) S: Rodent Laboratory Chow 5001® (RLC); (2) SBL: 90% RLC+ 10% dry bean leaves; (3) H: high-fat/high-fructose diet; (4) HBL: H+ 10% of dry bean leaves. Overall, a HBL diet enhanced impaired glucose tolerance and ameliorated obesity, risk factors in NAFLD development. Additionally, bean leaves exerted antioxidant (↑serum GSH) and anti-inflammatory (↓mRNA TNFα in the liver) effects, prevented hepatic fat accumulation by enhanced ↑mRNA PPARα (β oxidation), and enhanced lipid peroxidation (↓liver MDA). These findings suggest that bean leaves ameliorated hepatic lipotoxicity derived from the consumption of a deleterious diet.

High-fat/high-fructose diets promote early metabolic disorders in weight, lipid and glucose metabolism. Bioactive compounds such as polyphenols and fiber present in plant-based food prevent metabolic disorders development. The objective of the present study was to evaluate the effect of bean leaves on early metabolic alterations in Wistar male rats fed with high-fat/high-fructose diet. After proximate and chemical analysis of bean leaves, thirty-six Wistar male rats (ethical approval 06FCN2019 and 77FCN2019) were randomly assigned into one of four groups: 1) Standard diet (S) fed with Rodent Laboratory Chow 5001®, 2) Standard diet + 10% of dry bean leaves (SBL), 3) high fat (lard) and fructose diet (H) and 4) high-fat/high-fructose diet + 10% of dry bean leaves (HBL). The study was carried out for 6 weeks. Group H exhibited early metabolic alterations compared to S, final weight gain (↑15%), abdominal fat accumulation (↑11% waist circumference), triglycerides (↑30%), glucose (↑16%), insulin resistance (↑HOMA-IR 32%), fecal triglycerides (↑284%) and decreased total short chain fatty acid (↓SFCA, 17%). Bean leaves supplementation (HBL) compared to group H prevented body weight gain (↓12%), abdominal fat accumulation (waist circumference, ↓10%), early insulin resistance (glucose area under the curve, ↓6%). Probably mediated by the fiber and polyphenols present in the leaves, supplementary bean leaves-diet increased SFCA production (↑54%). Therefore, bean leaves are a low-cost alternative for human nutritional care and prevention of early metabolic alterations.