Toshiya Toda

Adlercreutzia equolifaciens gen. nov., sp. nov., an equol-producing bacterium isolated from human faeces, and emended description of the genus Eggerthella.

Nine strains capable of metabolizing isoflavones to equol were isolated from human faeces. Four of the strains were characterized by determining phenotypic and biochemical features and their phylogenetic position based on 16S rRNA gene sequence analysis. These strains were related to Eggerthella sinensis HKU14T with about 93 % 16S rRNA gene sequence similarity; they were asaccharolytic, obligately anaerobic, non-spore-forming, non-motile and Gram-positive coccobacilli. In enzyme activity tests, arginine dihydrolase, arginine and leucine arylamidases were positive but nitrate reduction, urease and beta-glucosidase were negative. The major menaquinone was DMMK-6 (dimethylmenaquinone-6), while that of members of the genus Eggerthella was MMK-6 (methylmenaquinone-6). Furthermore, the cell-wall peptidoglycan type of these strains was A1gamma, while that of members of the genus Eggerthella was A4gamma. On the basis of these data, a new genus, Adlercreutzia gen. nov., is proposed with one species, Adlercreutzia equolifaciens sp. nov. The type strain of Adlercreutzia equolifaciens is FJC-B9T (=JCM 14793T =DSM 19450T =CCUG 54925T).

Characterisation of proanthocyanidins from black soybeans: Isolation and characterisation of proanthocyanidin oligomers from black soybean seed coats

Proanthocyanidin oligomers (dimers to tetramers) were isolated from black soybean seed coats, using Sephadex LH-20 column chromatography and reversed-phase preparative HPLC. The isolated oligomers consisted of only (-)-epicatechin units, which were linked through either 4β→8 or 4β→6 (B-type) bonds. Procyanidin B2, procyanidin C1, and cinnamtannin A2 were identified as the main compounds of the proanthocyanidin dimers, trimers, and tetramers, respectively.

Procyanidin Promotes Translocation of Glucose Transporter 4 in Muscle of Mice through Activation of Insulin and AMPK Signaling Pathways.

Procyanidins are the oligomeric or polymeric forms of epicatechin and catechin. In this study, we isolated and purified dimer to tetramer procyanidins from black soybean seed coat and investigated the anti-hyperglycemic effects by focusing on glucose transporter 4 (GLUT4) translocation and the underlying molecular mechanism in skeletal muscle of mice. The anti-hyperglycemic effects of procyanidins were also compared with those of monomer (−)-epicatechin (EC) and major anthocyanin, cyanidin-3-O-β-glucoside (C3G). To investigate GLUT4 translocation and its related signaling pathways, ICR mice were orally given procyanidins, EC and C3G in water at 10 μg/kg body weight. The mice were sacrificed 60 min after the dose of polyphenols, and soleus muscle was extracted from the hind legs. The results showed that trimeric and tetrameric procyanidins activated both insulin- and AMPK-signaling pathways to induce GLUT4 translocation in muscle of ICR mice. We confirmed that procyanidins suppressed acute hyperglycemia with an oral glucose tolerance test in a dose-dependent manner. Of these beneficial effects, cinnamtannin A2, one of the tetramers, was the most effective. In conclusion, procyanidins, especially cinnamtannin A2, significantly ameliorate postprandial hyperglycemia at least in part by promoting GLUT4 translocation to the plasma membrane by activating both insulin- and AMPK-signaling pathways.

Identification of Human Intestinal Microbiota of 92 Men by Data Mining for 5 Characteristics, i.e., Age, BMI, Smoking Habit, Cessation Period of Previous Smokers and Drinking Habit

The intestinal microbiota compositions of 92 men living in Japan were identified following consumption of identical meals for 3 days. Fecal samples were analyzed by terminal restriction fragment length polymorphism with 4 primer-restriction enzyme systems, and the 120 obtained operational taxonomic units (OTUs) were analyzed by Data mining software focusing on the following 5 characteristics, namely, age, body mass index, present smoking habit, cessation period of previous smokers and drinking habit, according to the answers of the subjects. After performing Data mining analyses with each characteristic, the details of the constructed Decision trees precisely identified the subjects or discriminated them into various suitable groups. Through the pathways to reach the groups, practical roles of the related OTUs and their quantities were clearly recognized. Compared with the other identification methods for OTUs such as bicluster analyses, correlation coefficients and principal component analyses, the clear difference of this Data mining technique was that it set aside most OTUs and emphasized only some closely related ones. For example for a selected characteristic, such as smoking habit, only 7 OTUs out of 120 were able to identify all smokers, and the remaining 113 OTUs were thought of as data noise for smoking. Data mining analyses were affirmed as an effective method of subject discrimination for various physiological constitutions. The species of bacteria that were closely related to heavy smokers, i.e., HaeIII-291, were also discussed.

Comparison of the sympathetic stimulatory abilities of B-type procyanidins based on induction of uncoupling protein-1 in brown adipose tissue (BAT) and increased plasma catecholamine (CA) in mice

Objectives We previously found that elevated energy expenditure following a single oral dose of flavan 3-ols (FL), a mixture of catechins and B type procyanidins, is caused by sympathetic nerve activation. In the present study, we compared the activity of the FL components (-)-epicatechin (EC; monomer), procyanidin B2 (B2; dimer), procyanidin C1 (C1; trimer), cinnamtannin A2 (A2; tetramer), and more than pentamer fraction (P5). Methods Male ICR mice were treated with a single oral dose of FL, EC, B2, C1, A2, or P5. The animals were sacrificed and blood and brown adipose tissue (BAT) sampled. The plasma catecholamine (CA) levels and BAT uncoupling protein (UCP)-1 mRNA expression were determined. Results A single dose of 10 mg/kg FL significantly increased plasma CA and UCP-1 mRNA levels. B2, C1, and A2, but not EC and P5 (all at 1 mg/kg), significantly increased plasma adrenaline levels. Plasma noradrenaline was significantly elevated by B2 and A2, but not by EC, C1, or P5. UCP-1 mRNA levels were significantly increased by C1 and P5. In the dose response study of A2, 10−3 mg/kg A2 increased UCP-1 mRNA levels significantly, but not 10−2 and 10−1 mg/kg A2. In addition, combination treatment with 10−1 mg/kg A2 and yohimbine, an α2 adrenalin blocker, remarkably increased UCP-1 mRNA levels. Conclusion These results suggest that FL and its components, except EC, increase UCP-1 mRNA and plasma CA with varying efficacy.

Single oral administration of flavan 3-ols induces stress responses monitored with stress hormone elevations in the plasma and paraventricular nucleus

We previously confirmed that postprandial alterations in the circulation and metabolism after a single oral dose of flavan 3-ols (mixture of catechin and catechin oligomers) were involved in an increase in sympathetic nervous activity. However, it is well known that, in response to various stresses, activation of the hypothalamic-pituitary-adrenal (HPA) axis occurs together with sympathetic nerve activity, which is associated with activation of the sympathetic-adrenal-medullary (SAM) axis. In this study, we examined whether the HPA axis was activated after a single dose of flavan 3-ols. We administered an oral dose of 10 or 50u202fmg/kg flavan 3-ols to male ICR mice, removed the brains, and fixed them in paraformaldehyde-phosphate buffer. Other animals that were treated similarly were decapitated, and blood was collected. In the paraventricular nucleus (PVN), c-fos mRNA expression increased significantly at 15u202fmin after administration of either 10 or 50u202fmg/kg flavan 3-ols. Corticotropin-releasing hormone (CRH) mRNA expression levels significantly increased at 240u202fmin after administration of 10u202fmg/kg flavan 3-ols, and at 60u202fmin after administration of 50u202fmg/kg flavan 3-ols. Plasma corticosterone levels were also significantly increased at 240u202fmin after ingestion of 50u202fmg/kg flavan 3-ols. In this experiment, we confirmed that the ingestion of flavan 3-ols acted as a stressor in mammals with activation both the SAM and HPA axes.

The effects of fermented milk containing Lactococcus lactis subsp. cremoris FC on defaecation in healthy young Japanese women: a double-blind, placebo-controlled study

Abstract The objective of this double-blind, placebo-controlled study was to elucidate the effects of fermented milk containing Lactococcus lactis subsp. cremoris FC (FC) on defaecation in healthy young women. We included 31 women (18–31u2009years old) who were randomly selected into two groups. Subjects in the test group consumed fermented milk containing FC, while subjects in the placebo group consumed non-fermented gelled milk. In the test group, defaecation frequency (both in days and times per week) and stool volume significantly increased during the consumption of fermented milk containing FC compared with before consumption. These effects were also observed in subjects with mild constipation. Furthermore, in subjects with mild constipation, stool ammonia concentration was significantly lower in the test group than that in the placebo group after 4 weeks. These results suggest that fermented milk containing FC is beneficial for improving defaecation and faecal properties.

Black soybean seed coat polyphenols prevent AAPH-induced oxidative DNA-damage in HepG2 cells

Black soybean seed coat extract (BE), which contains abundant polyphenols such as procyanidins, cyanidin 3-glucoside, (+)-catechin, and (−)epicatechin, has been reported on health beneficial functions such as antioxidant activity, anti-inflammatory, anti-obesity, and anti-diabetic activities. In this study, we investigated that prevention of BE and its polyphenols on 2,2-azobis(2-methylpropionamide) dihydrochloride (AAPH)-induced oxidative DNA damage, and found that these polyphenols inhibited AAPH-induced formation of 8-hydroxy-2-deoxyguanosine (8-OHdG) as a biomarker for oxidative DNA damage in HepG2 cells. Under the same conditions, these polyphenols also inhibited AAPH-induced accumulation of reactive oxygen species (ROS) in the cells. Inhibition of ROS accumulation was observed in both cytosol and nucleus. It was confirmed that these polyphenols inhibited formation of AAPH radical using oxygen radical absorbance capacity assay under the cell-free conditions. These results indicate that polyphenols in BE inhibit free radical-induced oxidative DNA damages by their potent antioxidant activity. Thus, BE is an effective food material for prevention of oxidative stress and oxidative DNA damages.

Effect of Dietary Soy Protein Supplement in Dyslipidemic South Indian Population: A Randomized, Double-Blind, Placebo Controlled, Parallel-Group Trial

Forty subjects identified as dyslipidemic were assigned randomly to either soy powder (Soy) or red bean powder (Placebo). The soy group received daily a sachet of 18.1 g soy power containing 85 K cal and the placebo group received daily placebo sachet (23.1 g) of red bean powder containing 85.5 K cal in addition to the usual diet for four weeks. Intake of soy/placebo powder was assessed by measurement of 24-hour urinary isoflavone excretions at baseline and at the end of the intervention period. Relative to placebo, soy powder has significant effect over some Cardiovascular Disease (CVD) markers and Metabolic Syndrome (MetS) indices including abdominal circumference, triglycerides, HbA1c and insulin. These data support that the dietary consumption of soy has the property to reduce risk factors for CVD and MetS.

Beneficial Effect of Viscous Fermented Milk on Blood Glucose and Insulin Responses to Carbohydrates in Mice and Healthy Volunteers: Preventive Geriatrics Approach by "Slow Calorie"

WHO-coordinated Cardiovascular Disease and Alimentary Comparison (CARDIAC) Study covering over 61 populations of 25 countries in the world revealed the significant inverse association of the biomarkers of fish and soybean intakes in 24-hour urine with age-adjusted mortality rates of coronary heart diseases (CHD) (Yamori, 2006a; Yamori et al, 2006), indicating high fish and soybean consumptions might contribute to the No.1 average life expectancy of the Japanese with the lowest CHD mortality rates among developed countries (Yamori, 2006b). The mechanisms by which these food factors such as isoflavones and magnesium from soybeans as well as n-3 fatty acids and taurine from seafood could work as nutrients good for longevity have been studied experimentally and epidemiologically (Yamori, 2006c; Yamori, 2009; Yamori et al., 2010).