33-1
Physiological Function of Highly Purified Soy Proteins (Part III)
Reiko URADE*1 and Mitsutaka KOHNO2
1Laboratory of Food Design and Development, Division of Agronomy and Horticultural Science,
Graduate School of Agriculture, Kyoto University, Kyoto 611-0011
2 Food Science Institute, Fuji Oil Co., LTD., Osaka 598-8540
ABSTRACT
Soy protein isolate is known to have several beneficial effects on human health,
such as lowering the cholesterol and triacylglycerol levels in the serum. Soy protein
isolate is composed of the major seed storage proteins glycinin and β-conglycinin,
and lipophilic proteins (LP), to which a large amount of phospholipids is adsorbed.
In this study, the effects of untreated LP and delipidated LP (DLP) on serum
cholesterol and triacylglycerol levels were determined. Young male Wistar rats
(6-week-old) were fed high cholesterol diets containing 22.5% casein (casein diet),
11.25% casein and 11.25% LP (LP diet), or 11.25% casein and 11.25% DLP (DLP diet)
for 14 days. The serum triacylglycerol and cholesterol levels were significantly
lower in the DLP diet group than in the casein diet group, but not in the LP diet
group. The fecal excretion of triacylglycerol or cholesterol was significantly higher
in the DLP diet group than in the casein diet and/or LP diet groups.
Soy Protein
Research, Japan 15, 1-5, 2012.
Key words : lipophilic proteins, phospholipids, serum triacylglycerol, serum
cholesterol, rat
33-2
Prospective Study of the Preventive Effect of Intensive Dietary Soy Intake on Atherosclerosis in an Urban General Population (PartII)
Yoshihiro KOKUBO*1, Yoko HURUKAWA2 and Mariko BANNO3
1Department of Preventive Cardiology, National Cerebral
and Cardiovascular Center, Osaka 565-0873
2 Faculty of Health Science, Kyoto Koka Women's University, Kyoto 615-0882
33Shcool of Human Environmental Sciences, Department of Food Science and Nutrition, Mukogawa Women's University, Nishinomiya 663-8558
ABSTRACT
Background and Purpose: Soybean has been found to improve dyslipidemia, but
there is no study on the association between dietary intake of soybean and the
incidence of dyslipidemia in a general population. Using the subjects of the Suita
study, the relation of the incidence of life-style-related disease risk to soy product
categories was examined. Methods: Among the subjects who participated in the
Suita study, 2,953 men and women (mean age: 57.8 years old) underwent medical
examination between January, 1994 and December, 1996. A food frequency
questionnaire and a lifestyle questionnaire were conducted. Hypertension was
defi ned as blood pressure >140/90 mmHg or antihypertensive drug use. Diabetes
was defined as fasting or occasional blood glucose >126 mg/100mL or >200
mg/100mL, respectively, or use of anti-diabetic medication. Dyslipidemia was
defined as non-HDL cholesterol (=[total cholesterol]-[HDL cholesterol]) >170
mg/100mL. The risk of incident hypertension, diabetes, and dyslipidemia was
analyzed by the Cox proportional-hazards model with respect to soy products
categories. Results: Multivariable-adjusted hazard ratios (95% confi dence intervals
[CIs]) of hypertension and diabetes mellitus were 0.78 (0.61-0.99) and 0.60 (0.36-0.98)
respectively in subjects with daily intake of miso soup, compared with those seldom
consuming miso soup. Adjusted hazard ratios (95% CIs) of dyslipidemia were 0.80(0.66-0.97), 0.77 (0.62-0.96), and 0.71 (0.53-0.94) in subjects with intakes of natto of 1
to 2 times per week, 3 to 4 times per week, and daily respectively, compared with
those seldom consuming natto. Conclusions: In an urban general population, daily
miso soup intake may prevent hypertension and diabetes mellitus. Increase of natto
intake may prevent dyslipidemia for a dose response.
Soy Protein Research, Japan 15,
6-12, 2012.
Key words : Soy, miso soup, natto, hypertension, diabetes mellitus, dyslipidemia,
prospective study
33-3
Study of the Molecular Targets of Metabolic Improvement Caused by Soy Protein Intake (PartI)
Ryuichiro SATO*1, Makoto SHIMIZU1, Hiroyasu INOUE2 and Rieko NAKATA2
1Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657
2Department of Food Science and Nutrition, Nara Women's University, Nara 630-8506
ABSTRACT
In the current experiments we used β-conglycinin or lipophilic proteins (LP) as
a dietary protein source in comparison to casein. When Syrian hamsters were
fed a LP diet containing high fat and 2% cholesterol for 4 weeks, its supposed
serum cholesterol-lowering effect was not observed. In contrast, the β-conglycinin
diet significantly reduced weight gain as compared with the casein diet. When
C57BL/6N mice were fed a high-fat diet containing either casein or β-conglycinin
for 9 weeks, the β-conglycinin diet lowered serum glucose, cholesterol, and insulin
concentrations, and weight gain. The β-conglycinin diet produced positive changes
in hepatic gene expression as reported previously. When these diets were fed to
PPARα-deficient mice, most effects of the β-conglycinin diet were not abolished,
suggesting that β-conglycinin may exert its beneficial effects without involving
PPARα. We found a novel gene that was weakly induced by the β-conglycinin
diet, and have been focusing on its functions by which carbohydrate and lipid
metabolism are regulated in response to β-conglycinin feeding.
Soy Protein Research,
Japan 15, 13-16, 2012.
Key words : β-conglycinin, lipophilic proteins, PPARα, cholesterol
33-4
Isolation and Functional Characterization of Potent Receptors Involved in Insect-Derived Elicitor Recognition in Soybean Cells
Gen-ichiro ARIMURA1, 2, Abdelaziz RAMADAN1, 2, 3, Keiichiro NEMOTO3,
Hiroyuki TAKEDA3, Rika OZAWA1, Massimo MAFFEI4 and Tatsuya SAWASAKI3
1Center for Ecological Research, Kyoto University, Otsu 520-2113
2Graduate School of Science, Kyoto University, Kyoto 606-8502
3Cell-free Science and Technology Research Center, Ehime University, Matsuyama 790-8577
4The University of Torino, Torino, Italy 10124
ABSTRACT
Upon herbivore attack, plants respond to two initial, herbivore-derived factors (physical damage and chemical elicitors included in their saliva). In plants,
immunity is initiated through pattern recognition receptors in response to several
biotic stresses to provide the fi rst line of inducible defense. Despite the numerous
elicitors perceived by plants, however, none of the pattern recognition receptors
for insect salivary elicitors have so far been identified so far. As oligosaccharides
are predicted to be one of the insect salivary elicitors and a receptor kinase
CERK1 (Chitin Elicitor Receptor Kinase) has been identified as critical receptors for
oligosaccharide signaling in rice and Arabidopsis, in the current study we screened
the characteristics of soybean CERK1-homogous (receptor-like kinase [RLK]) genes
which enabled an interation with a component in the regurgitant of Spodoptera
litura . Eight members of CERK1 homologues synthesized by in vitro transcription
and cell-free protein synthesis exhibited auto-phosphorylation activity. Therefore,
the synthesized proteins were analyzed with the biacore system that enables
finding the ability of the biomolecule of elicitors to interact with a specific binding
protein. Our preliminary analysis showed that one of the nine CERK1-homologous
proteins interacted with regurgitant component(s) from S. litura . In future research,
we intend to assess the characteristic of this receptor, characterize the specific elicitor, and mine other sets of potent receptors involved in elicitor recognition in
plant cells.
Soy Protein Research, Japan 15, 17-20, 2012.
Key words : elicitors, herbivore, oligosaccharide, receptor-like kinase, soybean
33-5
Basic Analysis of Defenses Against Nematode Infection in Plants
Shinichiro SAWA*
Graduate school of Science and Technology, Kumamoto University, Kumamoto 860-8555
ABSTRACT
Because of their agricultural importance, the soybean cyst nematode Heterodera
glycines , which infects soybean (Glycine max ), and Meloidogyne incognita , which
infects many crops, have emerged as good research models to understand the
signaling, perception, and response events during plant-nematode interactions. The
recent advances in our understanding of the cellular, physiological, and molecular
bases of legume-nematode interactions are merging at the crossroads of plantmicrobe
interactions and plant developmental biology. On the one hand, the CLE
peptide hormone is the molecule responsible for the control of plant meristem
activity, and CLE genes are conserved in many plants. On the other hand, in
the animal kingdom, only nematodes that are infective of plants have the CLE
gene. This CLE gene of nematodes is likely to be functional in the plants. Once
nematodes infect roots, they redifferentiate root cells into multinucleated giant cells,
as source of nutrition, by injection of various eff ector proteins including the CLE
peptides of nematodes. In this study, to elucidate the molecular mechanism of the
infection process of nematodes, nematode infection experiments with Arabidospsis
mutant and marker transgenic plants were performed. The rate of nematode
infection suggests that genes related to dedifferentiation, redifferentiation, the auxin
signaling pathway and the cyclin signaling pathway are required for nematodes to
infect plants.
Soy Protein Research, Japan 15, 21-25, 2012.
Key words : nematode, Arabidopsis, CLE, peptide, molecular mechanism
33-6
Metabolome Quantitative Locus Analysis in Soybean
Yuji SAWADA*
RIKEN Plant Science Center, Yokohama 230-0045
ABSTRACT
Metabolite quantitative trait locus (mQTL) analysis has great potential for
discovering the associations involving diverse plant genes and metabolites. As a
practical metabolic phenotyping, we have established widely targeted metabolomics
using automated optimization of selected reaction monitoring (SRM) in 700 standard
compounds. To detect the un-known metabolites, we also established a large-scale
SRM assay system for thousands of un-targeted MS/MS tags (MS2Ts) obtained
by plant extracts. As the populations for linkage based QTL mapping, soybean
recombinant inbred lines (RILs) have been constructed from Glycine max (cultivated
species) and Glycine soja (wild type accession). G. soja is expected to be a useful
genetic resource for molecular breeding of soybean. Using our metabolomics
platform, a total of 16 SRMs derived from 4 standard compounds and 12 MS2Ts
were significantly associated with the four major mQTLs (LOD values > 10) in
TK780 (G. max) x B01167 (G. soja) RILs, which were distributed from NBRP (Legume
Base). The annotations of associated SRMs were flavonoids, phenolic compounds
and unknown metabolites, which were highly accumulated in G. soja . Unfortunately,
no significant mQTL was found in G. max x G. max RILs. These results suggested
that the genetic resources of G. soja are useful for epoch-making metabolic
engineering in soybean.
Soy Protein Research, Japan 15, 26-30, 2012.
Key words : Metabolomics, large-scale SRM assay system, QTL, G. soja
33-7
Functional Analyses of cGMP/NO Signaling and MYB Transcription Factor Regulating Gene Expression of Soybean isoflavone-biosynthetic Enzymes
Hamad Abu ZAHRA, Moeko DOI and Hiroshi YAMAGATA*
Division of Applied Chemistry in Bioscience, Graduate School of Agricultural Science, Kobe University, Kobe 657-8501
ABSTRACT
Expression of several genes encoding flavonoid-biosynthetic enzymes and the level
of isoflavone and anthocyanine in soybean (Glycine max L.) are regulated by cyclic
guanosine 3', 5'-monophosphate (cGMP) and nitric oxide (NO). Chalcone synthases,
GmCHS7 and GmCHS8, are key enzymes controlling the isoflavonoid level in
the seeds, and GmMYB176 regulating GmCHS8 expression affects isoflavonoid
synthesis. Here we analyzed the functional relationship between cGMP signaling
and GmMYB176 on the activation of GmCHS8 promoter. Quantitative RT-PCR
analysis showed that the transcript level of GmCHS8 was increased 9.5-fold with
cGMP, and the cycloheximide did not inhibit the induction of GmCHS8 by cGMP,
indicating de novo synthesis of protein is not necessary for this effect. The level of
GmMYB176 transcript was not increased by cGMP. Both cGMP and GmMYB176
could trans-activate GmCHS8 promoter in transient gene expression assay using
protoplast of soybean SB-P cells. Also it was found that cGMP activated Unit I
sequence but not MYB176 binding sequence in the GmCHS8 promoter. We have
previously reported the Unit I-independent activation of gene expression by cGMP
for soybean chalcone reductase (CHR), suggesting that cGMP responsible cis -
elements in the promoters of genes encoding flavonoid-biosynthetic enzymes are
diverse. DNA microarray analysis using the Arabidopsis T87 suspension culture
showed that the expression of many genes were enhanced or repressed by cGMP
and/or NO. cGMP/NO responsible sequences in the promoters of genes encoding
ferritin1 and nicotianamine synthase1 were determined and compared to each other.
Soy Protein Research, Japan 15, 31-37, 2012.
Key words : flavonoid, isoflavone, gene expression, cGMP, MYB transcription factor
33-8
Bioactive Substances Contained in Discharges Generated during Soybean Oil Refi nement-A Search for Weight-Loss Promoting Compounds-
Nagao TOTANI*
Department of Nutritional Physiology, Faculty of Nutrition,
Kobe-Gakuin University, Kobe 651-2180
ABSTRACT
The number of over-weight Japanese, especially men between 20-60 years old, has
been increasing. Proper diet and physical exercise have long been recommended to
reduce obesity, but these are often not easy to maintain in daily life. We reported
previously that soybean oil heated with soybean protein under reduced pressure
followed by fi ltration (Soy Oil) showed weight-loss promoting effects in rats, and
that ferulic and gallic acids contained in vegetable have a much more pronounced
effect when esterifi ed. In the present study, the weight-loss promoting substances
were found to exist in the polar fraction of Soy Oil. In addition, the existence of
the these substances in crude soybean and clay-adsorbed oils was investigated by
instrumental analyses as the method for Soy Oil preparation is partly similar to
the process used in manufacturing commercial soybean oil. Results show that the
crude soybean oil polar fraction contained acylglycerols, phenolic compounds and
fatty acids similar to those in the Soy Oil polar fraction. The clay-adsorbed oil polar
fraction consisted of acylglycerols as main components and phenolic compounds in
addition to aldehydes: remarkable decreases in double bond signals and aldehydes
are due to oxidation. Further study is expected because crude soybean oil should
be a source of weight-loss promoting substances, although the chemical structures
of the substances were not identified.
Soy Protein Research, Japan 15, 38-45, 2012.
Key words : weight-loss promoting compound, soybean oil, polar fraction, crude oil
33-9
Study of the Mechanisms of Yeast Glycogen Accumulation Caused by Soy Peptides
Shingo IZAWA*
Laboratory of Microbial Engineering, Department of Applied Biology,
Graduate School of Scientifi c Technology, Kyoto Institute of Technology, Kyoto 606-8585
ABSTRACT
We have previously reported that the cultivation of yeast cells in media containing
soy peptides improves the tolerance against freeze-thaw stress and prevents the
formation of lipid bodies in Sacchaomyces cerevisiae. Additionally, we found that
soy peptides increase the level of cellular glycogen. DNA microarray analysis
indicated that the up-regulation of glycogen biosynthesis system was caused by
the cultivation with soy peptides. Compared with yeast cells cultured with casein
peptone, cells cultured with soy peptides showed an increase in the levels of
cellular glycogen. The cultivation with soy peptides caused activation of general
stress responsive transcription factors Msn2/Msn4 and subsequently resulted
in the increased levels of the glycogen synthases (Gsy1 and Gsy2) and branching
enzyme (Glc3). Additionally, expression of various heat shock proteins such as
Hsp30 was also induced by soy peptides. These results suggest that cultivation
with soy peptides is likely a kind of stress condition for yeast cells, and that it is
possible to induce the accumulation of glycogen by the combination of soy peptides
and other stresses.
Soy Protein Research, Japan 15, 46-49, 2012.
Key words : soy peptides, baker's yeast, glycogen, heat shock proteins
33-10
Effect of Dietary Soy Protein on Gastrointestinal Hormones that Cause an Increase in the Amount of Insulin Secretion
Mina FUJINO1, Fumikazu HAYASHI1, Ayaka IKATA1, Akemi HOSODA1, 2,
Azumi YAMAGISHI1, 3, Tomoe FUKUMURA1, Dong-Ho KIM1 and Shigeru SAEKI*1
1Department of Food and Human Health Sciences, Graduate School of Human Life Science,
Osaka City University, Osaka 558-8585
2Faculty of Healthcare, Tokyo Healthcare University, Tokyo 154-8568
3Faculty of Education, Art and Science, Yamagata University, Yamagata 990-8560
ABSTRACT
The present study was undertaken to elucidate whether dietary proteins would
affect type 2 diabetes symptoms. Otsuka Long-Evans Tokushima Fatty (OLETF)
rats, a model for type 2 diabetes, and Long-Evans Tokushima Otsuka (LETO)
rats, a genetic control for OLETF, were fed a casein- or soy protein isolate (SPI)-containing diet with or without 30% lard for 9 weeks. Glucose tolerance and
insulin resistance (HOMA-IR) in LETO rats were unaffected by dietary protein
and fat content. Glucose tolerance and insulin resistance in OLETF rats were
spontaneously impaired, which condition was aggravated by a high-fat diet
containing casein, but not by that containing SPI. Plasma levels of active glucagonlike
peptide 1 (GLP-1) in LETO rats were unaffected by dietary protein and fat
content. Plasma levels of active GLP-1 in OLETF rats were significantly increased
by a high-fat diet containing SPI, but not by that containing casein, irrespective of
plasma insulin levels. These results indicate that SPI will be effective in stimulating
GLP-1 secretion and improving glucose tolerance and insulin resistance in type 2
diabetes.
Soy Protein Research, Japan 15, 50-54, 2012.
Key words : type 2 diabetes, incretin hormone, insulin
33-11
Transcriptome Analysis of the Effect of Soy Protein on Improvement of Magnesium-deficient Diet-induced Disorder in Rats
Tomoko ISHIJIMA*, Shogo YONEMITSU, Toshiaki NAKAMURA,
Yuji NAKAI and Keiko ABE
ILSI Japan-Endowed Chair of Functional Food Science and Nutrigenomics, Graduate School of
Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657
ABSTRACT
The dietary protein sources, casein and soy protein isolate (SPI), differed from each
other in terms of the effect of dietary Mg-deficiency on the metabolism of rats. In
detail, 4-week-old male Wistar rats were fed 4 formulas with different dietary Mg
levels and protein sources for 4 weeks. As a result, the serum non-esterifi ed fatty
acid level was significantly decreased when rats were fed the Mg-deficient SPI diet.
Hepatic DNA microarray analysis was conducted, with the result that, in dietary
Mg deficiency, casein feeding significantly changed the expression of 660 genes,
while SPI feeding changed that of 419 genes. The significantly changed genes
in rats fed the Mg-deficient diet included transcription factor sterol regulatory
element binding transcription factor 1 (Srebf1) and genes involved in cholesterol
metabolism. These two changes differ between the dietary protein sources.
Soy Protein Research, Japan 15, 55-60, 2012.
Key words : soy protein isolate, Mg deficiency, lipid metabolism, DNA microarray,
rat
33-12
Effects of Soy Protein Isolate on the Phylogenetic Composition of Gut Microflora
Fumito TANI*1, 2, Ho Le Quynh CHAU2, 3, Natsumi KAWAGUCHI1,
Masahiro NAKAMOTO1, 4 and Tetsuya MASUDA1, 2
1Laboratory of Food Environmental Science, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502
2Laboratory of Global Food Science, Department of Natural Resources, Graduate School of Global Environmental Studies, Kyoto University, Kyoto 606-8502
3Present address: Faculty of Animal Sciences, Hue University of Agriculture and Forestry, Hue City, Vietnam
4Present address: Food Safety and Consumer Affairs Bureau, Ministry of Agriculture, Forestry and Fisheries, Tokyo 100-8950
ABSTRACT
Numerous gut microflora reside in the gastrointestinal tract to form mutualistic
symbiosis with host animals. However, it remains unknown about how food
composition affects mutualistic symbiosis of gut microfl ora and also how changes in
gut microfl ora control the activity of mucosal immunity. To address these problems,
we compared the changes in the phylogenetic composition of gut microfl ora in mice
fed three different kinds of diets: a 60 kcal% high-fat (HF) diet, a 45 kcal% HF diet,
and a carbohydrate-rich control diet (10 kcal% fat). C57BL/6 mice fed HF diets after
weaning gained body weight more rapidly compared to those fed the control diet.
Quantitative analyses of blood plasma showed a significant increase in the level of
total cholesterol and triglycerides in groups fed HF diets. Quantitative real-time
PCR revealed that the ratio of the Firmicutes phylum to eubacteria increased in the
60 kcal% HF diet group, but not in the 45 kcal% HF diet group, despite the fact that
mice of both groups had almost the same body weights at 20 weeks of age. On the
other hand, the ratio of the Bacteroides genus decreased in all three diet groups.
Flow cytometric analyses demonstrated that the frequency of CD3+ T cells and CD103+ dendritic cells in mesenteric lymph nodes significantly decreased with the
increase in fat concentration in the diets. When soy peptide Hi-nute AM was given
at the concentration of 5% in drinking water, the ratio of the Bacteroides genus in
60 kcal% HF diet group rapidly dropped even at 8 weeks of age, suggesting the
possible control of phylogenetic components of gut microfl ora by soy peptide.
Soy Protein Research, Japan 15, 61-67, 2012.
Key words : Bacteroides, dendritic cells, Firmicutes, gut microflora, high-fat diet, mucosal immunity, mutualistic symbiosis, soy peptide Hi-nute AM
33-13
Soybean β-conglycinin Improves Lipid Metabolism in Wistar Rats
Nao INOUE, Yuka FUJIWARA, Asuwa FUNAYAMA, Masaki KATO and Ikuo IKEDA*
Laboratory of Food Science, Graduate School of Agricultural Science, Tohoku University, Sendai 981-8555
ABSTRACT
The effects of dietary soybean β-conglycinin on lipid and energy metabolism were
studied in male Wistar adult rats. Male Wistar rats (19 weeks old) were fed an
AIN-93G diet containing casein or β-conglycinin for 4 weeks. At the 3-week feeding,
carbohydrate consumption was higher and fat consumption was lower in the β-conglycinin-fed rats than in the casein-fed rats. Total energy consumption was
the same for the two groups. Final body weight was significantly lower in the β-conglycinin-fed rats than in the casein-fed rats. Serum adiponectin was higher in
the β-conglycinin-fed rats than in the casein-fed rats. Serum triacylglycerol (TAG)
concentration in the β-conglycinin-fed rats was significantly lower than in the
casein-fed rats. The activities of hepatic enzymes related to fatty acid synthesis was
lower and the activity of hepatic carnitine palmitoyltransferase were higher in theβ-conglycinin-fed rats than in the casein-fed rats. The VLDL-TAG secretion rate
from the liver after the administration of Tyloxapol, an inhibitor of lipolysis, was
significantly lower in the β-conglycinin-fed rats than in the casein-fed rats. These
results suggest that β-conglycinin improves carbohydrate metabolism through
an increase of adiponectin production and exerts serum TAG-lowering activity
through a suppression of VLDL-TAG secretion from the liver.
Soy Protein Research, Japan 15, 68-71, 2012.
Key words : β-conglycinin, Wistar rats, triacylglycerol, energy metabolism, lipid
metabolism
33-14
Effect of Digested Peptides Derived from β-conglycinin on Myocellular Glucose Uptake
Keisuke SAWADA, Yoko YAMASHITA and Hitoshi ASHIDA*
Department of Agrobioscience, Graduate School of Agricultural Science,
Kobe University, Kobe 657-8501
ABSTRACT
It has been suggested that dietary intake of soy protein is potentially beneficial
for prevention of obesity and hyperglycemia. β-Conglycinin, one of the major soy
proteins, has been reported to lower the blood glucose and insulin levels with an
increasing adiponectin level and decreasing plasma lipids levels in animal studies.
However, the underlying molecular mechanism is not yet fully understood. In this
study, we investigated the effect of digested peptide mixtures derived from β-conglycinin on myocellular glucose uptake and its molecular mechanism. Two
peptide mixtures (peptide mixtures-A and -B) were prepared by treating β-conglycinin with an artifi cial digestive juice and the enzymes from microorganisms,
respectively. When L6 myotubes were treated with these mixtures, both of them
increased glucose uptake dose-dependently. Mixture-A had a stronger effect than
mixture-B. Although we could not identify the active peptide in mixture-A, peptides
with hydrophilic properties contribute to the stimulation of glucose uptake.
Next, we investigated whether glucose uptake stimulation is accompanied by
translocation of the glucose transporter 4 (GLUT4) to the plasma membrane, which
is an insulin-responsive transporter and is distributed in adipose tissue and skeletal
and cardiac muscles specifically; we found that the peptide mixture-A stimulated
translocation of GLUT4 without altering its expression level. We also found that
AMP-activated kinase (AMPK) was phosphorylated but Akt did not, indicating that
translocation of GLUT4 by the peptides derived from β-conglycinin was dependent
on the AMPK-pathway. In an animal study using type-2 diabetes mellitus model, GK rats, we confirmed activation of AMPK and downstream GLUT4 translocation
and UCP-3 expression in soleus muscle. In conclusion, intake of β-conglycinin will
prevent hyperglycemia by stimulating GLUT4 translocation followed by glucose
uptake in muscle.
Soy Protein Research, Japan 15, 72-78, 2012.
Key words : β-conglycinin, peptide, anti-hyperglycemia, glucose transporter 4
(GLUT4), muscle
33-15
Administration of a Soy-Enriched Dipeptide Efficiently Increases Tyrosine Content in the Brain and Serum of Mice
Shigeki FURUYA*1, 2, 3 and Kayoko ESAKI2, 4
1Division of Systems Biology, Department of Bioscience and Biotechnology, Fukuoka 812-8581
2Division of Functional Biomaterials Design, Department of Innovative Science & Technology for Bio-industry, Graduate School of Bioresource and Bioenvironmental Sciences, Fukuoka 812-8581
3Bioarchitecture center, Kyushu University, Fukuoka 812-8581
4RIKEN Brain Science Institute, Wako, Saitama 351-0198
ABSTRACT
The aim of this study was to assess the neurochemical effects produced by oral
administration of dipeptide Ser-Tyr in genetic serine-deficiency model mice that
were created using a gene-targeting technique. Amino acid analysis demonstrated
that in the cerebral cortex and hippocampus forced oral administration of Ser-Tyr
dipeptide increased free L-Tyr content more effi ciently than that of sole L-Tyr at
the same intake dose. In contrast, free L-Ser content in these brain regions did
not differ significantly between Ser-Tyr dipeptide- and sole L-Ser-administered
groups. Additionally, Ser-Tyr dipeptide administration caused a greater increase in
L-Tyr concentration in serum than sole L-Tyr administration. The present findings
indicate that intake of dipeptide Ser-Tyr efficiently enhance free L-Tyr levels in
brain and systemic circulation.
Soy Protein Research, Japan 15, 79-84, 2012.
Key words : tyrosine, serine, branched chain amino acids, soy peptide, brain
33-16
The Basic Study of Efficient Use of Soybean Components to Maintain Geriatric Muscle Function
Hisanori KATO*1 and Shinya AOYAMA2
1Organization for Interdisciplinary Research Projects, The University of Tokyo, Tokyo 113-8657
2Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657
ABSTRACT
The result of our previous study has revealed that dietary protein modulates
the phosphorylation of insulin receptor substrates (IRSs). In addition, we found in
diabetic model mice that the expression of the gene for Atrogin-1, a component
of the muscle atrophy-related pathway, was reduced by dietary supplementation
of a soy Isoflavone, genistein. Considering the importance of prevention of skeletal
muscle atrophy in the elderly, effective use of soy components is worth exploring.
To clarify the effects of soy protein isolate (SPI), genistein, and their combination on
skeletal muscle atrophy, male Wistar rats with excised sciatic nerve were used as
a model of atrophy. Intakes of SPI (20%) and the combination of SPI and genistein
(0.05%) for 10 days had no effect on muscle atrophy induced by denervation. While
genistein intake tended to prevent atrophy of soleus, no preventive effect was
observed in gastrocnemius and anterior tibialis. The up-regulations of the genes for
Atrogin-1 and Muscle RING-fi nger protein-1 (MrRF-1) caused by denervation were
attenuated by genistein intake. DNA microarray analysis revealed that 1209 genes
were up-regulated and 353 genes were down-regulated by genistein intake. The
result of transcription factor analysis of the gene expression profi le data suggested
the involvement of the estrogen receptor in the effect of genistein.
Soy Protein Research, Japan 15, 85-89, 2012.
Key words : muscle atrophy, soy protein isolate (SPI), genistein, microarray
33-17
The Functions of Soy Isoflavones on Epigenetic Regulation and Protection of Neuronal Cells
Kaoru NAGAI*
Department of Epigenetic Medicine, Interdisciplinary Graduate School of Medicine
and Engineering, University of Yamanashi, Yamanashi 409-3898
ABSTRACT
Epigenetic regulation, such as DNA methylation and histone modifi cation, is crucial
for brain function. Histone deacetylation is one of the crucial steps for epigenetic
transcriptional regulation. It has been reported that histone deacetylase (Hdac)
inhibitor displays therapeutic effects on dementia-model mice. However, the
molecular mechanisms of the effects have not yet been clarified. Natural products,
such as short-chain fatty acids and some polyphenols show modulating effects
on Hdac families. Thus, soybean ingredients such as isoflavones might have a
modulating function on Hdac activities. Since inhibitors of class I and II Hdacs
and activators of class III Hdacs, called sirtuins, have been reported to show a
therapeutic effect on the neurodegeneration model, we analyzed the effects of the
soy isoflavones genistein, daidzein, and equol on the activities of Hdac families.
We found that daidzein showed class I, II Hdac inhibitory and class III Hdac Sirt1
activation effects. Then, we analyzed whether daidzein shows protective effects on
endoplasmic reticulum (ER) stress induced Neuro2a cell death. Since ER stress is
known to cause considerable neurodegeneration, molecules which protect the cells
from ER stress could be candidates for treating neurodegenerative diseases. The
commonly used Hdac inhibitor sodium butylate showed a protective effect, and
daidzein showed similar effects. The histone acetyltransferase activator CBT also
showed a protective effect, but co-treatment with daidzein with CBT did not show
an additive effect. This suggests that daidzein and CBT protected the cells via
similar pathways, probably an increase in histone acetylation. Our data raise the possibility that consumption of daidzein may reduce the risk of neurodegenerative
diseases such as dementia via modulating epigenetic mechanisms.
Soy Protein Research, Japan 15, 90-95, 2012.
Key words : neurodegenerative disease, histone deacetylase, Sirt1, endoplasmic
reticulum stress, isoflavone
33-18
Growth Inhibition Action of Lactic Acid Bacteria-Metabolic Products on Human Leukemia HL-60 Cells
Yuichi NODAKE*, Masashi FUKASAWA and Ryuzo SAKAKIBARA
Laboratory of Biochemistry, Department of Pharmacy, Faculty of Pharmaceutical Sciences, Nagasaki International University, Nagasaki 859-3298
ABSTRACT
PS-B1 is a fermented product cultured from soybean milk using lactic acid bacteria.
In this study, we found that PS-B1 significantly inhibited the growth of human
leukemia HL-60 cells in dose-dependent manner; we also examined the mechanism
of the anti-proliferation action of PS-B1 on HL-60 cells. Subsequently, several
results suggesting that PS-B1 induced apoptosis in HL-60 cells were obtained from
a pectrophotometrical analyses. In HL-60 cells treated with PS-B1, (1) an increase
in intracellular reactive oxygen species; (2) a reduction of glutathione level and
mitochondrial membrane potential; (3) an increase in caspase activity; and (4) DNA
fragmentation were detected.
Soy Protein Research, Japan 15, 96-102, 2012.
Key words : lactic acid bacteria-metabolic product, PS-B1, growth inhibition action,
apoptosis
33-19
The Effect of Soybean Protein on Urinary Ca Excretion
Sumiko KAMOSHITA1, Bui Thi NHUNG2, Pham Thi Anh THO3,Nguyen Thi THUAN3 and Fumio SHIMURA*1
1Human Life Faculty, Jumonji University, Saitama 352-8510
2National Institute of Nutrition, Hanoi, Vietnam
3Asian Nutrition and Food Culture Research Center, Jumonji University, Saitama 352-8510
ABSTRACT
Although the content of the sulfur amino acids (methionine and cysteine) in soybean
protein is not deficient, it is low compared with food from animal sources, such as
egg, meat, or fi sh. Intakes of sulfur amino acids by Japanese are much higher than
the requirements. High intake of sulfur amino acids produces sulfuric acid which
make the body pH lower than normal. To maintain normal pH, hydroxyapatite
(Ca10(PO4)6(OH)2), which is a constituent of bone is used. This suggests that the
prevention of over-intake of sulfur amino acids may protect against bone Ca loss.
Soybean protein may be useful in preventing the over-intake of sulfur amino acids.
In this study we tried to confi rm this hypothesis. The study was conducted with
cross-over design in Vietnamese female university students (20-day study periods
and 10-day washout period). The subjects were given the same basal diet with about
30 g protein together with 30 g soybean protein or egg white protein. All the urine
during the last 3 days was collected and pH and Ca concentration were measured.
The egg white protein group showed a lower pH and higher Ca concentration in
the urine as compared with the soybean protein group (p <0.01). In conclusion the
results of the study confi rmed our hypothesis that soybean protein maintains normal
body pH and prevents bone Ca loss.
Soy Protein Research, Japan 15, 103-107, 2012.
Key words : methionine, sulfur amino acids, soybean protein, Ca, urinary pH, hydroxyapatite
33-20
Effect of Soy Protein on Blood Lipid Concentration in China: a Randomized Controlled Trial
Kyoko TAKU*1, Meng JIA2, Yong XUE2, De-Fu MA2, Toyonori OMORI3,
Mitsutaka KOHNO4, Fang-Qun HAN5 and Yu-Mei ZHANG2
1Center for International Collaboration and Partnership, National Institute of Health and Nutrition, Tokyo 162-8636
2School of Public Health, Peking University, Beijing
3Department of Health Care Policy and Management, Nagoya City University Graduate School of Medical Sciences, Aichi 467-8601
4Food Science Research Institute, Fuji Oil Co., Ltd., Osaka 598-8540
5Social Community Health Service, Peking University Health Center, Beijing
ABSTRACT
We conducted a randomized controlled trial to verify the serum lipid lowering
effect of ingesting a test food containing β-conglycinin (a constituent of soy protein)
in China. One hundred women aged 40-65 years old with abnormal blood lipid
participated the trial. Participants were randomly allocated to three groups of
placebo (n=34, 4 casein tablets a day), low dose (n=33, 4 tablets containing 2.3 g β -conglycinin) and high dose (n=33, 8 tablets containing 4.6 g) with balanced age,
baseline weight and serum lipids. All participants were instructed to take the test
tablets two times a day and not to change their daily life style, including diet and
sports. The ages, baseline weight and serum lipids of participants did not differ
among the three groups. The serum triacylglycerol (TG) of the low dose group
after 6 weeks (2.76±0.77, mean±SD) significantly decreased, by 0.44 mmol/L
(14.5%) from the baseline (p =0.000), which was also significantly lower than that
of the placebo group (p =0.000); furthermore, the TG of the low dose group after
12 weeks (2.41±0.78) decreased significantly, by 0.78 mmol/L (21.7%) from the
baseline (p =0.000), which was also significantly lower than that of the placebogroup (p =0.001). The TG of the high dose group after 6 weeks (2.77±1.35, mean ±SD) decreased significantly, by 0.46 mmol/L (17.4%) from the baseline (p =0.000),
which was also significantly lower than that of the placebo group (p =0.000);
furthermore, the TG of the high-dose group after 12 weeks (1.99±0.85) decreased
significantly, by 1.25 mmol/L (34.5%) from the baseline (p =0.000), which was also
significantly lower than that of the placebo group (p =0.001). We did not observe
effects of β-conglycinin ingestion (either low dose or high dose) on serum total and
HDL cholesterol. The test food containing β-conglycinin (4.6 g/d) met the present
evaluation criteria of effectiveness for Chinese "health food", and was demonstrated
to decrease serum TG.
Soy Protein Research, Japan 15, 108-116, 2012.
Key words : soy protein isolate, β-conglycinin, serum triacylglycerol, Foods for
specifi ed health uses (FOSHU), health food
33-21
Does Soy Intake Relate to the Prevalence of Metabolic Syndrome ?
Tohru SAKAI*1, Mariko NAKAMOTO1, Emi SHUTO1, Rie TSUTSUMI1, Nanako KATAOKA2, Chisato KOSUGI2, Yukiko BANDO2, Yosuke SHIKAMA2, Yuka KISHUKU2, Yumi KUWAMURA3, Takako MINAMIKAWA3, Takako ICHIHARA3, Ayako TAMURA3 and Makoto FUNAKI2
1Department of Public Health and Applied Nutrition, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8503
2Clinical Research Center for Diabetes, Tokushima University Hospital, Tokushima 770-8503
3Department of Nursing, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8503
ABSTRACT
We conducted a cross-sectional study in a workplace setting in Tokushima
Prefecture. A total of 1,460 Japanese workers (1,076 men and 384 women)
participated in this study. In men, the group that consumed large amount of soy
products also consumed more vegetables, fruits, and seasonings than the group
that consumed small amounts of soy products. However, consumptions of cereals
and meat were smaller in the group that consumed large amounts of soy products.
In women, the group that consumed large amount of soy products consumed more
vegetables and seasonings than the group that consumed small amounts of soy
products. Associations between prevalence of metabolic syndrome and level of soy
intake were assessed with the use of multiple logistic regression models. Of the 1,076
male subjects examined, 207 (19.2%) were diagnosed as the metabolic syndrome
in men. The relative risk of metabolic syndrome in the group that consumed high
levels of soy products was 1.433 (0.930-2.206) when compared to the group that
consumed fewer soy products.
Soy Protein Research, Japan 15, 117-124, 2012.
Key words : soy, legumens, metabolic syndrome
33-22
Study on Cookie-making, less of Beany Flavor, used Soy Protein Isolate
Kazuko HIRAO*
Aikoku Gakuen Junior College, Tokyo 133-8585
ABSTRACT
In order to prepare cookies with less of a beany flavor using soybean protein
isolate (SPI), the cooking process, baking temperature and time, the ratio of
water in the cookie, and the ingredient ratio (using Scheffé's simple lattice design)
were examined by use of physical measurement, sensory evaluation and gas
chromatography analysis. SPI, wheat flour, sugar, shortening and egg and/or water
were used, and the cookies were baked at 140-180℃. To judge by the results, when
water and sugar were added to the cookie dough and the cookies were thoroughly
heated at 160℃, the beany flavor of SPI cookies was reduced and a fragrant
aroma was added. According to analysis of the ingredient ratio by Scheffé's simple
lattice design, the more wheat flour was added, the softer the cookie texture, and
moreover there was also less of a beany flavor. Furthermore, the more sugar was
added, the shorter the cookie texture, and moreover there was also more of a
fragrant scent. The ingredient ratio of lattice point 3 (40% SPI, 0% wheat flour and
60% sugar) was evaluated as the most preferable in the item of taste of sensory
evaluation. Gas chromatography analysis suggests that this is due to a masking
effect by the Malliard reaction. The ingredient ratio of 40% SPI, 15% wheat flour
and 45% sugar in the cookies was evaluated as the most preferable with regard
to hardness, shortness, and overall sensory evaluation. The above results suggest
that cookies made with an ingredient ratio of approximately SPI 25.5%, wheat flour
9.6%, sugar 28.6%, shortening 22.7%, egg and water 13.6% have the most favorable
taste. Moreover, the substitution of butter for shortening and trehalose for sugar
increased the sweet-smelling flavor and reduced the beany flavor in the cookies.
Soy Protein Research, Japan 15, 125-132, 2012.
Key words : beany flavor, soy protein isolate, cookie, Scheffé's simple lattice design,
physical properties, sensory evaluation
33-23
Cooking Possibilities and Taste Acceptability of Soluble OKARA
Masayo KANEDA*1, Eiko MURAI2, Chieko TOYAMA3, Misako HIROTA4, Yoko TAKEDA5, Keiko YANAGISAWA6 and Sayako AOKI7
1Junior College of Kagawa Nutrition University, Tokyo 170-8481
2Marugame Municipal Ayauta Junior High School, Kagawa 761-2406
3Toki Municipal Hida Elementary School, Gifu 509-5115
4Moriyama Municipal Moriyama Elementary School, Shiga 524-0041
5Omihachiman Municipal Aduti Junior High School, Shiga 521-1341
6Omitama Municipal Minori Junior High School, Ibaraki 319-0132
7Katsushika Ward Kitano Elementary School, Tokyo 125-0052
ABSTRACT
The fiber intake of Japanese is much lower than the DRI. The DRI for fiber in
school lunches is 6.0 and 7.5 g for elementary and junior high school children,
respectively. However their average intakes are only 4.6 and 5.9 g, respectively.
During TOFU processing, OKARA (soybean fiber) is mostly wasted. Recently
soluble OKARA (SOF) has been produced and this is expected to help increase
fiber intake. However, the cooking possibilities and acceptability by children are
not known. In this study we tried to incorporate various quantities of OKARA into
some popular foods to find the highest acceptable quantity (Study 1). From the
results of Study 1, it was possible to use about 16 wt% SOF in various foods and in
Study 2, 14 locally produced foods were cooked with about 16 wt% SOF (Study 2).
Twelve of 14 foods were evaluated highly. In conclusion 16 wt% SOF can be easily
integrated into cooking and meets taste requirements.
Soy Protein Research, Japan 15, 133-139, 2012.
Key words : school lunch, okara, byproduct of tofu, fiber, solublefiber, nutrition
teacher, school children, cook
33-24
Relationship between the Expression of the Ferritin Gene and Iron Contents During Seed Maturation
Taro MASUDA*1, Fumiyuki GOTO2 and Toshihiro YOSHIHARA2
1Laboratory of Food Quality Design and Development, Division of Agronomy and Horticultural Science, Graduate School of Agriculture, Kyoto University, Kyoto 611-0011
2 Biotechnology Sector, Environmental Science Research Laboratory,
Central Research Institute of Electric Power Industry, Chiba 270-1194
ABSTRACT
Soybean seed contains a large amount of iron. It is suggested that the iron storage
protein ferritin contributes to the net iron content in the seed of soybean. We
identified four cDNAs encoding ferritin subunits of soybean (Glycine max Merrill
cv. Kita-no-shiki). The gene expression analysis demonstrated that two of them
(sfer1 and sfer2) were transcribed actively in the seed, especially at an initial
stage of seed maturation, while the expression of sfer3 gene was not detected.
In accordance with the gene expression analysis, accumulation of the ferritin
protein was observed mainly at the initial stage of seed formation. The purified
ferritin protein from the dry seed was composed of two types of subunits, SFER1
and SFER2, which contained approximately 2,500 Fe atoms per ferritin oligomer.
The elementary analysis using Inductively Coupled Plasma Atomic Emission
Spectrometry demonstrated that the iron content was also increased at an initial
stage of seed maturation. These results suggested that ferritin was synthesized
and iron was synchronously accumulated in ferritin at an early stage of the seed
maturation.
Soy Protein Research, Japan 15, 140-144, 2012..
Key words : ferritin, iron content, seed maturation, subunit, elementary analysis
33-25
Preparation of Insoluble Soy Protein Gel Enhancing Hydration with Monosaccharide as a Separation Material
Ryota TAKATA, Hirokazu SETO, Keisuke OHTO and Hidetaka KAWAKITA*
Department of Chemistry and Applied Chemistry, Graduate School of Science and Engineering,
Saga University, Saga 840-8502
ABSTRACT
Insoluble soy protein (Fuji Pro F) was reacted with keto glucose for crosslinking the
inter-proteins by glutaraldehyde to obtain a soy protein gel. Keto glucose-introduced
gel represented the roughness on the surface, resulting in a more heterogeneous
gel. However, keto glucose-introduced gel had the most swelling when immersed in
water and acetone alternatively. After the adsorption of phloxine and hemoglobin,
phloxine had the more effective desorption in acetone solution.
Soy Protein Research, Japan 15, 145-150, 2012.
Key words : separation, gel, soy protein, keto glucose
33-26
Effects of Soy Protein Isolate on Glucose Homeostasis and Kidney Functions of Type II Diabetic Model GK Rats
Masatoshi KUBOTA*1, Risa ITO2, Reiko WATANABE4, Shinobu FUJIMURA1, 2, 3 and Motoni KADOWAKI1, 2, 3
1Center for Transdisciplinary Research, Niigata University, Niigata 950-2181
2Graduate School of Science and Technology, Niigata University, Niigata 950-2181
3Faculty of Agriculture, Niigata University, Niigata 950-2181
4Department of Health and Nutrition, University of Niigata Prefecture, Niigata 950-8680
ABSTRACT
The number of type 2 diabetes mellitus (T2DM) patients is rapidly increasing
and is becoming a serious problem all over the world. T2DM may lead to various
complications such as diabetic retinopathy, neuropathy and nephropathy. In
the therapy of diabetic nephropathy, most people pay attention to the dietary
protein intake, but only a few focus on the effect of protein sources on diabetic
nephropathy. Therefore, we attempted to clarify the effects of different protein
sources on diabetes and diabetic nephropathy. Male non-obese type 2 diabetic Goto-Kakizaki (GK) rats were fed high sucrose diets for 15 wk with 20% casein (C) or
soy protein isolate (SPI). The fasting blood glucose levels and the markers related
to diabetes and kidney functions in the blood and urinary albumin excretion were
determined. Kidney tissue sections were obtained for histological analysis. SPI had
no effects on fasting blood levels of glucose, insulin and adiponectin. However, the
levels of plasma alkaline phosphatase, hematocrit and urinary albumin excretion in
GK rats fed SPI were significantly improved compared with those of the C group.
In addition, renal glomerular damage was significantly suppressed in the SPI group.
These results suggest that SPI has a suppressive effect on progression of diabetic
nephropathy.
Soy Protein Research, Japan 15, 151-155, 2012.
Key words : soy protein isolate, diabetes, diabetic nephropathy, Goto-Kakizaki rat
33-27
Effect of Soy Peptides on the Recombinant Protein Production in Yeast
Keisuke ITO*, Aya HIKIDA and Yasuaki KAWARASAKI
School of Food and Nutritional Sciences, University of Shizuoka, Shizuoka 422-8526
ABSTRACT
Eukaryotic membrane proteins are involved in a wide range of biological functions.
For successful analysis, a large amount of receptor protein production is necessary.
Although the yeast expression system is a useful tool for expression of heterologous
proteins including receptors, the robust cell wall presents an obstacle to extracting
proteins from the cell. Therefore, harvesting the protein in the exponential
growth phase of the yeast, in which a cell has a comparatively thin cell wall, is an
important factor for the protein yield. In this study, production of eight G proteincoupled
receptors was compared using two types of media, one of which contained
soy peptides and the other contained a free amino acids mixture. Yeast cell growth
was improved in the media with the soy peptides, and the expression levels of
six of the receptors were increased during the exponential phase by an average
of 2.3 times over the free amino acids-based media. The enhancement of protein
expression by soy peptides is explained by an alleviation of metabolite stress from
amino acid source depletion caused by heterologous protein expression. These
results suggest that soy peptides are useful for microorganism-mediated protein
production.
Soy Protein Research, Japan 15, 156-159, 2012.
Key words : soy peptides, Saccharomyces cerevisiae , protein expression, exponential growth phase, membrane protein
33-28
Effect of Dietary Soy Isoflavones on Rat Skeletal Muscle Fiber Type
and Muscle Mass
Wataru MIZUNOYA*, Kenta SHIMOMURA, Taiki AKASAKA, Yusuke SATO ,Mako NAKAMURA, Ryuichi TATSUMI and Yoshihide IKEUCHI
Graduate School of Agriculture, Kyushu University, Fukuoka 812-8581
ABSTRACT
Soy isoflavones (daidzein, genistein and glycitein) are thought to be candidates
for peroxisome proliferator-activated receptor (PPAR)δ ligands, which are a
key regulator of skeletal muscle fiber type. We addressed whether dietary soy
Isoflavone intake affects skeletal muscle fiber type via the PPARδ pathway in rats.
Seven-week-old male Wistar rats were fed a diet with or without 0.4% (w/w) crude
soy isoflavones (Soyafl avone HG) for 4 weeks, then blood and tissue samples were
collected. In our previous report, we showed that the muscle mass was significantly
lower in the soy isoflavone-fed group, and the proportion of myosin heavy chain
I (slow type) in EDL muscle was significantly increased in the soy isoflavonefed
group. In this study, we analyzed fiber-type related protein expression with
Western blotting and soy Isoflavone concentration in serum and skeletal muscle.
Our result suggests that soy isoflavone existed in serum at concentrations that
could be expected from PPARδ activity. However, UCP3, the representative
target protein of PPARδ, was not upregulated in the soy isoflavone-fed group,
which implied that the change in skeletal muscle property was due to a pathway
independent of PPARδ.
Soy Protein Research, Japan 15, 160-164, 2012.
Key words : soy Isoflavone, skeletal muscle, fiber type, myosin heavy chain, PPARδ
33-29
Mechanism for Equol-Induced Anorectic Effect
-Analysis of Free and Conjugated Equol Concentrations-
Takafumi MIZUSHIGE*, Mina FUJITANI, Yuki YAMASHITA, Yoshiya YAMAUCHI, Satoru MURAKAMI, Taro KISHIDA and Kiyoshi EBIHARA
Laboratory of Nutritional science, Faculty of Agriculture, Ehime University, Matsuyama 790-8566
ABSTRACT
In the previous study, we have shown that an equol, a metabolite of soybean
daidzein with intestinal microorganisms, decreased food intake specifically in female
rats. The equol may be an active substance on the anorectic action. It is well
known that equol metabolizes to glucuronidation and sulfate conjugation in liver
and small intestine. In the present study, to examine a biodistribution of daidzein
and equol after feeding of daidzein diet, we measured daidzein, conjugated and free
equol concentrations in liver, bile, blood, urine and feces when female rats were fed
a daidzein diet. As to the results, equol concentratioins in bile were higher than
those in liver, blood and urine. Free equol concentrarion in bile in female rats was
significantly lower than that in male rats, suggesting that female-specific free equol
in an enterohepatic circulation might be the active substance of the anorectic effect.
We performed a procedure in which bile taken from female donor rats fed the
daidzein diet was infused into the duodenum in other female rats fed the control
diet. The bile infusion significantly decreased food intake in female rats, suggesting
that the enterohepatic circulated equol in bile induced the anorectic effect. In
conclusion, we found that an accumulation of enterohepatic circulated free equol
may down-regulate food intake.
Soy Protein Research, Japan 15, 165-169, 2012.
Key words : soy isoflavone, daidzein, equol, conjugate, bile acid
33-30
Effect of Compounds Contained in Soybean on Macrophage Activation
Yukio FUJIWARA*1, Yoshihiro KOMOHARA1, Koji OHNISHI1,Tsuyoshi IKEDA2 and Motohiro TAKEYA1
1Department of Cell Pathology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto 860-8556
2Department of Natural Medicine, Faculty of Pharmaceutical Sciences of Sojo University, Kumamoto 860-0082
ABSTRACT
Tumor-associated macrophages (TAMs) polarized to the M2 phenotype promote
tumor cell proliferation and are associated with a poor prognosis in patients with
high grade glioma. We previously reported that corosolic acid, a triterpenoid
compound, inhibits the M2 polarization of human monocyte-derived macrophages
(HMDM). In the present study, we examined whether triterpenoid compounds
and flavonoid compounds contained in soybeans also show inhibitory effects on
M2 polarization in HMDM. Soyasapogenol A and B, triterpenoid compounds,
significantly inhibited the expression of CD163, one of the phenotype markers
of M2 macrophages, as well as suppressed the secretion of IL-10, one of the
anti-inflammatory cytokines preferentially produced by M2 macrophages,
thus suggesting that soyasapogenol A and B suppress the M2 polarization of
macrophages. Furthermore, soyasapogenol A and B inhibited the proliferation
of U373 human glioblastoma cells and SaOS2 human osteosarcoma cells, and the
activation of signal transducer and activator of transcription-3 (STAT3) in both
human macrophages and tumor cells. These results indicate that soyasapogenol
A and B regulate macrophage activation and suppress tumor cell proliferation
by inhibiting STAT3 activation. Therefore, soyasapogenol A and B may be a
potentially new agent that can be used for the prevention and treatment of various
malignant tumors, including glioma and ostersarcoma.
Soy Protein Research, Japan 15, 170-175, 2012.
Key words : Macrophage, pSTAT3, Soyasapogenol, osteosarcoma, glioma
33-31
Effect of Tofuyo (Fermented Soybean Food) Extract on Influenza Virus-Infected Animals
Akikazu SAKUDO*1 and Masayasu SESOKO2
1Laboratory of Biometabolic Chemistry, School of Health Sciences, Faculty of Medicine, University of the Ryukyus, Okinawa 903-0215
2RyuKyu-Cement Co., Ltd.
ABSTRACT
This study investigated the possible in vivo activity of Tofuyo (fermented soybean
food) extract against influenza. Tofuyo was diluted with water and subjected to
homogenization, fi ltration and centrifugation. The resultant supernatant was used
as Tofuyo extract. Nude mice (BALB/cSlc-nu /nu ) were given drinking water
supplemented with Tofuyo extract the day before intranasal inoculation with
influenza. In addition, a control group was given water to drink without Tofuyo
extract. Forty percent of the control group was dead within 14 days, while all
the mice drinking Tofuyo extract-containing water survived. Tofuyo contains
proteins, carbohydrates, vitamins and minerals that provide nutritive value and
may contribute to the promotion of good health. We are currently analyzing the
mechanisms by which Tofuyo extract relieves the symptoms of infection with
influenza.
Soy Protein Research, Japan 15, 176-180, 2012.
Key words : Influenza, Kojis, Okinawa, Tofuyo, Virus
33-32
Induction and Suppression of Human Disease-Associated Genes in Cultured Cell Line Cells by Bean-Extract Stimulation
Naoko OKUMURA*, Hitomi YOSHIDA and Satoru MATSUDA
Department of Environmental and Life Sciences, Graduate School of Humanities and Sciences, Nara Women's University, Nara 630-8506
ABSTRACT
The aim of this study was to determine the effects of several bean ingredients
and chemical inhibitors on the expression of presenilin, a molecule involved in γ-secretase activity and the generation of amyloid-β peptide in Alzheimer's
disease, and on the expression of Cip-interacting zinc fi nger protein 1 (Ciz1), which
stimulates DNA replication and has been implicated in tumorigenesis of breast
cancer cells. Western blotting revealed the downregulation of presenilin 1 protein
expression by stimulation with genistein in vitro , while the effects on presenilin
1 gene expression examined by reverse transcriptase-polymerase chain reaction
(RT-PCR) were unaltered in Daudi cells. Genistein likely downregulates presenilin
via the inhibition of ubiquilin 1 expression in lymphoid cells. Our findings provide
new insights that may help to establish preventive strategies against Alzheimer's
disease. In order to investigate the possibility of using medicinal Isoflavone against
breast cancer, we studied whether some isoflavones could affect the expression
of the Ciz1. The in vitro effect of isoflavone treatment on the reduction of Ciz1
expression was detected by reverse transcriptase-polymerase chain reaction (RTPCR).
Western blotting also confi rmed the down-regulation of the protein in dose
dependent manner of the genistein treatment in Daudi lymphoid cell line.
Soy Protein Research, Japan 15, 181-185, 2012.
Key words : soybean, genistein, gene expression
Soy Protein Research (Japan)