β-(1,3)-D-glucan from Pleurotus ostreatus correlates with lower plasma IL-6, IL-1β, HOMA-IR, and higher pancreatic beta cell count in High-Fat and High-Fructose Diet (HFFD) rats

Introduction: The increasing consumption of high-fat and high-fructose foods contributes to the increasing prevalence of global obesity. Low-grade chronic inflammation in obesity is a significant risk factor for insulin resistance and type 2 diabetes. Therefore, this study aimed to determine the effect of β-(1,3)-D-glucan from oyster mushroom (Pleurotus ostreatus) extract on rats fed with a high-fat and high-fructose diet. Design and Methods: This experimental study was conducted on 35 male Sprague-Dawley rats aged eight weeks. The rats were divided into groups given a normal (N) diet, a high-fat and high-fructose diet (HFFD), D1 (HFFD+125 mg/kg BW β-glucan), D2 (HFFD+250 mg/kg BW β glucan), and D3 (HFFD+375 mg/kg BW β-glucan) with an intervention of 14 weeks. IL-6 and IL-1β levels were measured by the ELISA method, while HOMA-IR (Homeostatic Model Assessment for Insulin Resistance) was calculated by the fasting insulin (ng/mL) x fasting blood glucose (mg/dL)/405 formula. Pancreatic beta-cell counts were measured by hematoxylin and eosin (H&E) staining. Results: The results showed no differences in IL-6 and IL-1β between the treatment groups. However, there were significant differences in HOMA-IR and pancreatic beta-cell counts between groups. There were negative correlations between the dose of β-glucan and IL-6, IL-1β, and HOMA-IR levels. Also, there was a positive correlation between the dose of β-glucan and the number of pancreatic beta cells. Conclusions: Administration of β-(1,3)-D-glucan from oyster mushroom (Pleurotus ostreatus) extract prevented hyperglycemia and insulin resistance, also reduced inflammation in rats fed with HFFD regardless of weight gain.