Pre-germinated brown rice reduced both blood glucose concentration and body weight in Vietnamese women with impaired glucose tolerance.

We have reported that newly diagnosed type 2 diabetes mellitus (DM) patients in Vietnam have a low body mass index (BMI) of around 23 and that the major factor for this is high white rice (WR) intake. Brown rice (BR) is known to be beneficial in the control of blood glucose levels; however, it has the property of unpleasant palatability. Pre-germinated brown rice (PGBR) is slightly germinated by soaking BR in water as this reduces the hardness of BR and makes it easier to eat. This study was designed to evaluate the effect of a 4-mo PGBR administration on various parameters in Vietnamese women aged 45-65 y with impaired glucose tolerance (IGT). Sixty subjects were divided into a WR or PGBR group. For the first 2 wk, WR was replaced by 50% PGBR, then for 2 wk by 75% PGBR and from the second month 100%. Before the beginning of the study and at the end of the study, 1) anthropometric measurements, 2) a nutrition survey for 3 nonconsecutive days by the 24 h recall method and 3) blood biochemical examinations were conducted. Fasting plasma concentrations of glucose and lipids and the obesity-related measurements and blood pressure were favorably improved only in the PGBR diet group. The present results suggest that replacing WR with PGBR for 4 mo may be useful in controlling body weight as well as blood glucose and lipid levels in Vietnamese women with IGT.

Effects of pre-germinated brown rice on blood glucose and lipid levels in free-living patients with impaired fasting glucose or type 2 diabetes.

White rice (WR) is made by polishing brown rice (BR) and has lost various nutrients; however, most people prefer it to BR, maybe because of the hardness of BR. Pre-germinated brown rice (PGBR) improves the problem of BR. It is made by soaking BR kernels in water to germinate and becomes softer than BR. In this study we compared the effects of WR and PGBR on blood glucose and lipid concentrations in the impaired fasting glucose (IFG) or type 2 diabetes patients. Six men and 5 women with impaired fasting glucose (IFG) or type 2 diabetes were randomly allocated to 6 wk on WR or PGBR diet separated by a 2 wk washout interval in a crossover design. Each subject was instructed to consume 3 packs of cooked WR or PGBR (180 g/pack) daily in each intervention phase. Blood samples were collected 4 times (in study weeks 0, 6, 8 and 14) for biochemical examination. Blood concentrations of fasting blood glucose, fructosamine, serum total cholesterol and triacylglycerol levels were favorably improved on the PGBR diet (p<0.01), but not on the WR diet. The present results suggest that diets including PGBR may be useful to control blood glucose level.

Effects of pre-germinated brown rice on depression-like behavior in mice.

We investigated the antidepressant-like effects of pre-germinated brown rice (PGBR) and polished rice (PR) pellets, respectively, in comparison with control (AIN-93G) pellets in the forced swimming test and the learned helplessness paradigm in mice. Mice were fed respective pellets for 30 days. The immobility time on the 2nd day of the forced swimming test was shorter in mice fed with PR or PGBR pellets than in mice fed with control pellets. In the learned helplessness paradigm, the number of escape failures in mice fed with PGBR pellets was significantly smaller than that in mice fed with control pellets. Compared to the control group, an increase in serotonin (5-HT) levels, but not in 5-hydroxyindoleacetic acid (5-HIAA) levels, and a decrease in the 5-HIAA/5-HT ratio were observed in the frontal cortex of the PGBR group. There were no differences among the three groups in terms of 5-HT and 5-HIAA levels and their ratios in the hippocampus and striatum. The levels of noradrenaline and 3-methoxy-4-hydroxyphenylglycol were not affected by the food pellets in all the brain regions tested. Additionally, we could not detect any differences in the expression of the 5-HT1A receptor and the 5-HT transporter in the frontal cortex of the three groups. These results suggest that the increase of 5-HT levels in the mouse frontal cortex contributes to the antidepressant-like effects of PGBR pellets.

Hypocholesterolemic action of pre-germinated brown rice in hepatoma-bearing rats.

The effect of pre-germinated brown rice (PGBR) on cholesterol metabolism was studied in Donryu rats subcutaneously implanted with the ascites hepatoma cell line AH109A and compared with that of white rice (WR). The effect of brown rice (BR), the source of PGBR, was also studied. Hepatoma-bearing rats fed a WR diet exhibited hypercholesterolemia compared with normal rats fed the same diet. Feeding hepatoma-bearing rats a PGBR or BR diet suppressed hepatoma-induced hypercholesterolemia, and enhanced fecal bile acid excretion and the activity of cholesterol 7alpha-hydroxylase, the rate-limiting enzyme of bile acid biosynthesis, in the microsomal fraction of the liver without affecting cholesterol synthesis in the host liver of hepatoma-bearing rats. These results suggest that PGBR as well as BR suppresses hypercholesterolemia induced by hepatoma growth by up-regulating cholesterol catabolism.

Postprandial blood glucose and insulin responses to pre-germinated brown rice in healthy subjects.

Effects of pre-germinated brown rice (PGBR) on postprandial blood glucose and insulin concentrations were compared with brown rice (BR) and white rice (WR) in two studies. In the first study, we investigated the time course of postprandial blood glucose and insulin concentrations after ingesting 25% (W/V) glucose solution, PGBR, BR or WR in 19 healthy young subjects. In the second study, dose-dependent effect of PGBR on the time course of postprandial blood glucose concentrations was compared among 4 different mixtures of PGBR and WR in 13 healthy young subjects. They were solely PGBR, 2/3 PGBR (PGBR: WR = 2 : 1), 1/3 PGBR (PGBR : WR = 1 : 2) and solely WR. Each sample was studied on a different day. The samples were selected randomly by the subjects. All the rice samples contained 50 g of available carbohydrates. The previous day the subjects ate the assigned dinner by 9:00 pm and then were allowed only water until the examination. The next morning, they ingested each test rice sample with 150 ml of water in 5-10 min. Blood was collected into capillary tubes from finger at 0, 30, 60, 90 and 120 min after the ingestion. The incremental areas under the curve (IAUC) of blood glucose concentrations (IAUC-Glc) for 120 min after the administration of PGBR and BR were lower than those after WR. In contrast the IAUC-Glc of BR and PGBR were not different (Study 1). The higher the ratio of PGBR/WR, the lower the glycemic index became (Study 2). These results suggest that intake of PGBR instead of WR is effective for the control of postprandial blood glucose concentration without increasing the insulin secretion.

Effects of pre-germinated brown rice on beta-amyloid protein-induced learning and memory deficits in mice.

We evaluated the effects of pre-germinated brown rice (hatsuga genmai, PGR) on learning and memory and compared them with those of polished rice or cornstarch. In mice that were fed pellets of polished rice or PGR for two weeks, the learning ability in the Morris water maze test was significantly enhanced compared with mice that were fed cornstarch pellets. In the Y-maze test, the intake of food pellets for two weeks failed to affect spontaneous alternation behavior. Beta-amyloid(25-35) (Abeta(25-35): 3 nmol/mouse, i.c.v.) protein impaired spontaneous alternation behavior in mice that were fed pellets of cornstarch or polished rice. In contrast, PGR pellets prevented the Abeta(25-35)-induced impairment of spontaneous alternation behavior. These results suggest that polished rice and PGR have facilitating effects on spatial learning. In particular, it is surmised that PGR may prevent Alzheimer's disease associated with Abeta.