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Background: In order to evaluate the regulational role of adiponectin and leptin on obesity, we examined the significance of daily adherence to the Sticky Japanese Diet (SJD) on the preventions of obesity and metabolic syndrome by assessing the fat adiponectin/leptin and plasma leptin levels using normal and high-fat diet (HFD) mice. Methods: Five-week-old male ICR strain mice were placed in individual cages and randomly divided into eight groups based on feeding of SJD or not. At the end of each treatment period, plasma triglyceride, cholesterol, and leptin levels were measured by biochemical analysis. The adiponectin and leptin levels in adipose tissue were measured using RT-PCR. Results: In normal mice, an eight-week treatment of SJD increased adiponectin levels in adipose tissue. However, four weeks after discontinuing the SJD, these levels decreased. Furthermore, continuous feeding of the SJD for eight weeks increased plasma leptin levels but not that of adipose tissue. And then, discontinuing the SJD for more than eight days resulted in a decrease in plasma leptin levels. In HFD mice, an increase in body weight and visceral fat was seen at eight days after discontinuing the SJD which was undertaken for a total of eight weeks. At this time, the plasma leptin levels in these mice were substantially higher than in normal mice, although these levels were getting to be decreased over four weeks. Conclusion: This study revealed that discontinuous adherence to the SJD induced decreases in both adiponectin and leptin levels. Together with our previous publication, this paper suggests that daily adherence to the SJD might be essential for maintaining good health. Keywords: NuruNeba (Sticky Japanese Diet); Washoku (Japanese foods); normal diet; high-fat diet; leptin; adiponectin; obesity; mice Abbreviations: SJD: Sticky Japanese Diet; HFD: High-Fat Diet; CE-2: CLEA Rodent Diet CE-2; TG: Triglyceride; UCP1: Uncoupling Protein-1; BAT: Brown Adipose Tissue

The present study was carried out to find out the protective effects on oxidation disorders in menopausal model rats with chronic kidney disease （CKD） of a diet supplemented with almond paste. Nine-week-old female rats were divided into 3 groups: Control, AL, and Intact groups. The rats in the Control group and the rats in the AL group received 360 mg/kg BW of adenine intragastrically for 4 consecutive days so that they would develop CKD. After 7 days of recovery, the 3 groups of rats received ovariectomies （OVX） under anesthesia. Beginning three days after the OVX, for 8 weeks, the rats were given 13g per day of 20％ casein protein diet supplemented with 0％ almond paste （for the Control group and the Intact group） or 0.5％ almond paste （for AL group）. All the rats were killed under anesthesia and their TBARS in liver and kidney, BAP and dROM in serum, and some biochemical parameters in serum and urine were measured and the values of the AL group and the Control group were compared. Both groups showed 1） no significant differences in body weight changes, organ weights and blood analyses. The AL group showed 2） 22％ lower value in serum creatinine concentration, 3） 28.5％ higher value in creatinine clearance, 4） significantly higher value of TBARS in the liver. And the two groups showed 5） no significant differences in BAP and d-ROM values. From the above results, the authors conclude that the almond paste supplemented diet did not have significant influence on the degrees of the lipid peroxidation, the oxidation stress and the anti-oxidation ability of the menopausal model rats with CKD used in this study. On the other hand, it may be possible to improve renal function in menopausal model rats with CKD using a diet supplemented with almond paste.

The effect of milling and pressing soybeans at high temperatures (50–90C) was examined for laboratory-scale soymilk preparation. Soymilk that was milled and pressed at high temperatures showed more precipitate and a slightly lower protein content. The surface sulfhydryl content and surface hydrophobicity of the soymilk protein increased with milling temperature, which indicates some acceleration of the thermal denaturation of proteins. Ultracentrifugation and laser diffraction particle size analysis of the soymilk showed that milling at 90C resulted in highly dispersed protein aggregates and emulsions. Practical Applications Processing method for soymilk was improved to decrease beany flavor derived from lipoxygenase. Now soybean is milled at high temperatures to inactivate lipoxygenase activity, but there are no useful data on the quality of the resulting soymilk. In this study, milling at 90C showed more disperse soymilk than at 80C by considering droplet size distribution and protein denaturation behavior. These data are useful for estimation of the quality of soymilk beverage and for improvement of soymilk processing for more palatable beverages.

We examined the effects of lactic acid fermentation of soymilk on the lipid profile and lipid metabolism-related gene expression in rat liver. Male Sprague-Dawley rats aged 7 weeks were fed a control diet (AIN-93), soymilk diet, or fermented soymilk diet for 1 week or 5 weeks. The hepatic triglyceride and cholesterol contents in the soymilk (SM) group and the fermented soymilk (FSM) group were significantly lower than those in the control group after 5 weeks, but these changes had not become apparent until after 1 week. The fatty acid synthesis-related genes were more markedly down-regulated after 1 week than after 5 weeks, whereas the cytochrome p450 family 7 subfamily a polypeptide 1 (CYP7al) gene related to cholesterol catabolism was more markedly up-regulated after 5 weeks than after 1 week. This up-regulation was higher in the FSM group than in the SM group. It is assumed that the bioactive components produced by lactic acid fermentation induced the up-regulation of CYP7a1.

It is known that soy protein has the hypolipidemic action on blood and liver. We investigated to clarify physiologically effective concentration of soymilk. Male Sprague-Dawley rats aged 7weeks were fed a control die（t AIN-93G, soy protein free）, or a test diet in which 10.78%（corresponding to soy protein 5%）or 21.55%（corresponding to soy protein 10%）of the diet was replaced with soymilk, respectively. The rats were fed the control diet or the test diet for 5weeks. The administration of soymilk significantly suppressed total cholesterol level in plasma and decreased liver lipid and visceral fat. These effects depended on the concentration of administrated soymilk. It was suggested that soymilk improved the lipid metabolism in rat. Moreover, it was found that the administration of amount of soymilk corresponding to more than 10% soy protein was necessary to obtain a significant physiological effect in a short period.

This study examined the effects of fermented soymilk and okara on lipid metabolism in rats. Fermented soymilk and okara was prepared from a mixture of soymilk and okara blended in a ratio of 2 to 1 on dry basis by lactic acid fermentation using Lactobacillus delbrueckii. Male Sprague-Dawley rats were fed a diet based on the AIN-93 diet（ control diet） or two kinds of test diets in which 20% of a control diet was replaced by unfermented soymilk/okara mixture or fermented soymilk/okara for 7 weeks. We investigated changes in plasma and hepatic lipid levels of rats, and the regulation of gene expression in mesenteric adipose tissue and liver by DNA microarray. Groups of test diet significantly reduced plasma cholesterol levels compared with the control diet. In addition, the hepatic triglyceride in rats fed test diets was significantly lower than that of control diet. DNA microarray analysis indicated that the test diet ingestion down-regulated the expression of genes related to lipid metabolism in mesenteric adipose tissue and liver. These results suggested that a mixture of soymilk and okara has the effect improving lipid metabolism. Especially, fermented soymilk and okara seems to promote the restraint of abdominal visceral fat accumulation in comparison with unfermented soymilk and okara. Therefore, fermented soymilk and okara is a functional food showing effect preventing metabolic syndrome.

Polyamines, putrescine, spermidine and spermine, are important constituents of all mammalian cells and are essentially involved in a variety of regulatory step during normal and malignant cell proliferation. Okara and soymilk fermented with Lactobacillus were combined to form soy yogurt, which is rich in polyamine content. We investigated the effect of soy yogurt on polyamine levels in intestines and blood of rats. The ingestion of soy yogurt induced the increase of mucosal polyamine level in small intestine. Although the polyamine level in cecum was increased by the ingestion of soy yogurt, the polyamine levels in large intestine and blood were not increased. It was found that the ingestion of polyamine-rich soy yogurt could affect the polyamine level in only small intestinal mucosa. The large intestine seems to regulate the polyamine level to prevent own cells from hyperproliferation. It was assumed that blood kept polyamine level constant in spite of the level changes in intestines.

Soymilk-like white opaque liquid was prepared from whole soybean seeds without imbibition by the nama-shibori method. The solid content of the resulting liquid (non-imbibed soymilk) increased with an increase in blender revolutions and milling time, becoming almost equivalent to that of standard soymilk (imbibed soymilk) after milling at 12,000 rpm or more for 8 min. The precipitate obtained from the non-imbibed soymilk was lower than that from imbibed soymilk after milling for 4 min; however, it was higher after milling for 8 min. The non-imbibed soymilk showed bimodal particle size distribution, differing from imbibed soymilk prepared by milling at 12,000 rpm or less, which showed a unimodal distribution. The findings suggest that non-imbibed soymilk is of slightly lower quality than imbibed soymilk prepared from imbibed soybean seeds, but overall the differences were considered minimal.

豆乳を乳酸菌で発酵させた発酵豆乳による脂質代謝改善作用の有効投与量を調べるため，SD系雄性ラットに12.5％または25.0％発酵豆乳含有飼料（飼料中大豆タンパク質5％または10％含有）を5週間投与した．既報では大豆タンパク質8％含有発酵豆乳飼料で肝臓コレステロール濃度については有意な低下が得られているが，肝臓TG濃度では有意な低下は得られていない．本研究では大豆タンパク質10％含有発酵豆乳飼料で肝臓TG濃度についても有意な低下効果が認められた．一方，大豆タンパク質10％含有発酵豆乳飼料で血漿TC濃度の有意な低下が認められた．以上の結果から効果的なラットの脂質代謝改善作用を得るためには，飼料中の大豆タンパク質含有量10％以上となる発酵豆乳飼料の摂取が必要であることが明らかになった．

We examined the effects of lactic acid fermented soymilk, in which part of the soymilk was replaced with okara (soy yogurt), on plasma and hepatic lipid profiles in rats fed a cholesterol-free diet. Additionally, we investigated the effects of soy yogurt on hepatic gene expression in rats using DNA microarray analysis. Male Sprague-Dawley rats aged 5 weeks (n=5/group) were fed a control diet (AIN-93) or a test diet in which 20% of the diet was replaced by soy yogurt for 7 weeks. Soy yogurt consumption did not affect body weight or adipose tissue weight as compared with control diet. In the soy yogurt group, the liver weight and hepatic triglyceride content were significantly lower than the control group, and the level of plasma cholesterol was also lower. Furthermore, DNA microarray analysis indicated that soy yogurt ingestion down-regulated the expression of the SREBP-1 gene and enzymes related to lipogenesis in the rat liver, while expression of beta-oxidation-related genes was up-regulated. These results suggest that soy yogurt is beneficial in preventing hepatic lipid accumulation in rats.

Soymilk was prepared by non-heated squeezing and then heated at various temperatures. For one-step heating, the precipitate produced by heating soymilk increased for heating at 70 and 80°C and was much less at 90°C or higher temperatures, showing that the dispersion stability of soymilk was dependent on the heating temperature. In the case of two-step heating (combinations of 115°C and a lower temperature), soymilk heated at 115°C in the first step and 70 or 80°C in the second step resulted in increased precipitation. Changes in protein surface hydrophobicity were considered to be related to the precipitate formation of soymilk heated at the two different temperatures, indicating the significance of heat denaturation and aggregate formation of proteins on the dispersion stability of soymilk.