Antihypertensive effect of giant embryo brown rice and pre-germinated giant embryo brown rice on spontaneously hypertensive rats

"Shangshida NO.5" is a giant embryo mutant resulting from giant embryo gene (GE) dysfunction in "Chao2-10" rice. Here, we compared the antihypertensive effects of "Chao2-10" brown rice (C2-10), "Shangshida NO.5" brown rice (GER), and pre-germinated "Shangshida NO.5" brown rice (PGER) in spontaneously hypertensive rats (SHR). Male SHR at 6 weeks of age were divided into four groups and were fed with (a) a control diet (control), (b) a 40% C2-10-supplemented diet (C2-10), (c) a 40% GER-supplemented diet (GER), or (d) a 40% PGER-supplemented diet (PGER) for 8 weeks, and their physiological and biochemical parameters were measured. The results showed that the C2-10-, GER-, and PGER-supplemented diets significantly decreased systolic blood pressure (SBP) and diastolic blood pressure (DBP) during the experiment. At the end of the experimental period, the SBP and DBP of the C2-10, GER, and PGER groups were 7.6, 23.3, and 31.1 mmHg and 9.8, 21.1, and 29 mmHg lower than those in the control group, respectively, suggesting the GER and PGER diets were better able to inhibit blood pressure elevation than the C2-10 diet. The serum creatinine levels in the C2-10, GER, and PGER groups and the blood urea nitrogen content in the PGER group were significantly lower than those of the control group, indicating that C2-10-, GER-, and especially PGER-supplemented diets improved renal function. In addition, the antioxidant activity of the C2-10 group and especially of the GER and PGER groups also improved. The above results suggest that "Shangshida NO.5" rice, particularly pre-germinated rice, is a good dietary supplement for preventing the development of hypertension.

Instant White Rice with Pigmented Giant Embryonic Rice Improves Glucose Metabolism and Inhibits Oxidative Stress in High-Fat Diet-Fed Mice

The effects of instant cooked rice made from a combination of white rice and pigmented giant embryonic Keunnunjami rice, in comparison with those of instant regular white or brown rice and instant non-pigmented giant embryonic brown rice, on the glucose metabolism and antioxidant defense status in high-fat diet-fed mice were investigated. 56 male C57BL/6N mice were randomly divided into 7 dietary groups: normal control, high fat (23 %, HF), and HF supplemented with normal white (HF + NW) or brown rice (HF + NB), non-pigmented giant embryonic rice (HF + GB), and white rice with 8 % Keunnunjami (HF + KJ8) and 18 % Keunnunjami (HF + KJ18). After 7 weeks, HF mice showed marked increases in blood glucose (156 mg/dL), plasma insulin (12.1 mg/mL), and lipid peroxidation, and a significant decrease in hepatic glycogen (14.2 mg/g) relative to the control group (p < 0.05). However, addition of instant NB, GB, KJ8, andKJ18) rice suppressed this high-fat diet-induced hyperglycemia and oxidative stress through altering glucose-regulating enzymes (glucokinase, glucose-6-phosphatase, and phosphoenolpyruvate carboxykinase) and activation of antioxidant enzymes (superoxide dismutase, glutathione peroxidase, catalase, glutathione reductase, and paraoxonase). Compared with HF mice, HF + KJ8 and HF + KJ18 groups exhibited significantly lower glucose (139-141 mg/dL), insulin (10.6-10.9 mg/mL), and lipid peroxidation and higher glycogen (15.3-16.4 mg/g) (p < 0.05). The hypoglycemic and antioxidant effects of instant KJ8 and KJ18 rice were generally comparable to those of instant NB and GB rice. These findings illustrate that instant rice made from white rice with 8 % Keunnunjami rice may be useful as a functional food with therapeutic potential against hyperglycemia and oxidative damage.