Hypoglycemic Effect and Mechanism of β-Glucan Degradation Products from Highland Barley in Type 2 Diabetic Mellitus Mice

Objective: To explore the hypoglycemic effect of β-glucan degradation products from highland barley on type 2 diabetes mice and its mechanism. Methods: The mice model of type 2 diabetes mellitus was developed through a high-fat and high-sugar diet, followed by an intraperitoneal injection of streptomycin. The successfully modeled mice were randomly divided into diabetes model group, metformin group, low, medium and high dose HBDP groups, and another normal control group with ten mice in each group, and the mice were gavaged for 5 weeks. Subsequently, fasting blood glucose, insulin related index, lipid metabolism, serum antioxidant and other indicators were measured, and pathological observations were made on the liver tissues of each group of mice. RT-PCR was used to detect the expression levels of related genes. Results: Compared with the model group, the intervention of HBDP alleviated the symptoms of weight loss in diabetes mice and diminished the pathological harm to liver tissue. The fasting blood glucose, insulin levels, triglycerides, total cholesterol, low-density lipoprotein cholesterol, alanine aminotransferase, aspartate aminotransferase levels were significantly reduced (P<0.05), while the content of high-density lipoprotein cholesterol and superoxide dismutase and catalase were considerably increased (P<0.05) in a dose-dependent manner following HBDP treatment. The RT-PCR results showed that HBDP significantly upregulated the expression levels of IRS-1, PI3K, and Akt genes in liver tissue (P<0.05), and exhibited a certain dose-effect relationship. Conclusion: HBDP plays a hypoglycemic role by activating IRS-1/PI3K/Akt signaling pathway, thereby improving insulin resistance, glucose and lipid metabolism in diabetes mice. Therefore, HBDP can be developed and utilized as a hypoglycemic health food.