Effect of Differents Cowmilk and Soymilk (soy yogurt) Formulation on Blood Glucose Level and Glut4 Gene Expression in Rats Soleus Muscle.

Abstract

Soy yogurt is fermented soy milk and its nutrient-rich with isoflavones. Soy yogurt decreases blood glucose levels by utilizing the conversion of isoflavones. This study aimed to analyze the effect of soy yogurt on blood glucose level and Glut4 gene expression on rats' soleus muscle. Twenty-five rats (eighteen-weeks old) were divided into 5 groups, e.g., the control (P0), positive control (P1, 100% yogurt) and three treatment groups (P2, 50% soy yogurt+50% yogurt; P3, 75% yogurt+25% soy yogurt and P4, 75% soy yogurt+25% yogurt). All treatment groups were treated with different soy yogurt formula and administered for 12 weeks by gavaging. Under anesthetized, rats were sacrificed, then blood samples and soleus muscle were collected and stored at -80°C until use. RNA was extracted from soleus muscle and run for Glut4 mRNA expression using (RT)-PCR. Data were analyzed using one way ANOVA and followed by post hoc test LSD (Least Significant Differences test). There is no difference in rat body weight among groups after 12 weeks of soy yogurt consumption. Blood glucose levels were decreased at least 25% lower level compared to the control baseline by the various formulation of soy yogurt. Interestingly, there is a distinct pattern of Glut4 mRNA expression level in the soleus muscle, P1 increased the expression but not with other formulations decreased the expression (P2, P3 and P4). Taken together, a different formulation of soymilk and cowmilk effectively reduces blood glucose level and modulates Glut4 mRNA expression. In addition, a specific combination of bacteria type for fermenting soy yogurt could be a key to effectiveness for modulating blood glucose levels.