Abstract

EFFECT OF NATURAL POLYPHENOL EXTRACTS ON HIGH-FRUCTOSE-INDUCED METABOLIC DYSREGULATION

Abiodun V. Y.*, Okunola O. J., Akinmoyero A. B., Olanrewaju I. O., Owolabi S. S., Adesanya E. O., Idowu E. B.

ABSTRACT

High-fructose consumption has been implicated in the development of metabolic disorders characterized by obesity, insulin resistance, dyslipidemia, oxidative stress, inflammation, and hepatic dysfunction. This study evaluated the protective effects of natural polyphenol extracts against high-fructose-induced metabolic dysregulation in experimental Wistar albino rats. Twenty adult male rats were randomly assigned into five experimental groups: normal control, high-fructose control, high-fructose plus grape seed polyphenol extract, high-fructose plus green tea polyphenol extract, and high-fructose plus hibiscus polyphenol extract. Metabolic dysregulation was induced through high-fructose feeding, while polyphenol extracts were administered orally throughout the treatment period. Biochemical analyses included fasting blood glucose, insulin, HOMA-IR, lipid profile, hepatic triglycerides, oxidative stress biomarkers (MDA, SOD, CAT, and GSH), inflammatory cytokines (TNF-α and IL-6), liver function enzymes (ALT and AST), glucose tolerance test, and histopathological examination of liver tissues. Data were analyzed using one-way Analysis of Variance (ANOVA) followed by Tukey's post hoc test at a significance level of p < 0.05. The results showed that high-fructose feeding significantly increased body weight, blood glucose, insulin resistance, total cholesterol, triglycerides, LDL-cholesterol, hepatic triglycerides, malondialdehyde, inflammatory cytokines, liver enzymes, liver index, and histopathological damage, while significantly reducing HDL-cholesterol and antioxidant enzyme activities. Treatment with grape seed, green tea, and hibiscus polyphenol extracts significantly ameliorated these alterations by improving glucose metabolism, restoring antioxidant defenses, reducing oxidative stress and inflammatory responses, improving lipid metabolism, protecting liver architecture, and enhancing glucose tolerance. Among the treatment groups, green tea polyphenol extract demonstrated the greatest protective effect across most biochemical parameters. The study concludes that natural polyphenol extracts possess significant hypoglycemic, hypolipidemic, antioxidant, anti-inflammatory, and hepatoprotective properties, suggesting their potential as promising therapeutic agents for the prevention and management of diet-induced metabolic disorders.

Keywords: Natural polyphenols, High-fructose diet, Metabolic dysregulation, Oxidative stress, Inflammation, Dyslipidemia, Hepatoprotection, Wistar rats.