## 4 Discussion  
This study was conducted to investigate the effects of fermented rice germ extracts on hyperglycemia and hepatic glucose metabolism in T2 DM mice. The db/db mice were used as a T2 DM model, as they develop obesity and dyslipidemia due to a mutated leptin receptor gene. Further, the db/db mouse is the most popular animal model used for the study of blood glucose, diabetes, and obesity. Currently, db/db mice are widely employed in T2 DM research [4; 8; 9; 22; 23]. Previous studies have reported that ferulic acid and fermented rice germ extracts affect hyperglycemia and hepatic glucose metabolism in patients with diabetes. In particular,  
Figure 5: The effects of fermented rice germ extracts on hepatic glycolysis and gluconeogenesis in db/+ mice and db/db mice. (**a**) Relative mRNA expression of glucokinase (_Gk_); (**b**) Relative mRNA expression of glucose-6-phosphatase; and (**c**) Relative mRNA expression of phosphoenolpyruvate carboxykinase (_Pepck_). db/+, C57 BL/6 KsJ-db/+ mice and normal diet; db/db, C57 BL/6 KsJ-db/+ mice and normal diet with RG_30E, C57 BL/6 KsJ-db/+ mice and modified diet with RG_50E, RG_50E, C57 BL/6 KsJ-db/+ mice and modified diet with RG_50E; FA, C57 BL/6 KsJ-db/+ mice and modified diet with ferulic acid. Data with letters are significantly different (_p_ < 0.05) according to [PERSON]’s multiple range test. ferulic acid, a compound abundant in rice germ, was shown to regulate glucose metabolism in the liver [24; 25]. Rice contains a variety of phenols, which are often metabolized and not bioavailable. Fermentation using _L. plantarum_ increases the amount of physiologically active compounds such as ferulic acid, \(\alpha\)-tocopherol, and \(\gamma\)-oryzanol in rice, improving its antioxidant activity [11; 12; 26]. In addition, ethanol can effectively extract phytochemicals or phenolic compounds from plants when used with water. This is related to polarity, as the use of an ethanol-water mixture lowers polarity, creating an environment where low-polarity phenol chemicals can be dissolved [27; 28]. In this study, fermented rice germ was extracted with two different ethanol:water ratios to determine the more effective one with regard to glucose metabolism. Diabetic mice fed diets with ferulic acid or other modified diets did not lose weight compared to the db/db controls. However, the significant decrease in food intake and liver weight observed in FA, RG_30E, and RG_50E mice indicated that ferulic acid and fermented rice germ extracts could regulate the diabetes-associated increase in food intake and liver weight. Epididymal adipose tissue weight was not significantly different between groups but showed a tendency to decrease in FA, RG_30E, and RG_50E mice (Table 2). The intake of fermented rice germ, which is a rich source of minerals, vitamins, and phytochemicals, has been reported to reduce body weight, liver weight, and fat as a result of lower food intake [29; 30]. Dyslipidemia, a condition characterized by elevated TG, very low-density lipoprotein (VLDL) cholesterol, and TC and decreased high-density lipoprotein (HDL) levels is a frequent symptom of T2 DM patients [23]. RG_30E and RG_50E mice had lower hepatic TG and TC levels than those in the FA group. Further, RG_50E mice exhibited lower hepatic TC levels than their RG_30E counterparts (Figure 3). Fermented rice was previously shown to reduce TC levels [31]. Lowering TG and TC levels can reduce the risk of developing cardiovascular disease in T2 DM patients [32; 33]. To confirm the effect of fermented rice germ extracts on hyperglycemia, blood glucose levels in the fasting state (Figure 1) and OGTT (Figure 2) were assessed. Lower blood glucose levels were observed in RG_30E and RG_50E mice than in those of the FA group. In particular, blood glucose levels were significantly lowered at 3, 5, and 8 weeks after RG_50E intake. Further, RG_50E significantly reduced the AUC value following oral glucose administration.