High ß-Glucan Barley Supplementation Improves Glucose Tolerance by Increasing GLP-1 Secretion in Diet-Induced Obesity Mice.

The aim of this study was to investigate the underlying mechanism for the improvement of glucose tolerance following intake of high ß-glucan barley (HGB) in terms of intestinal metabolism. C57BL/6J male mice were fed a fatty diet supplemented with HGB corresponding to 5% of dietary fiber for 83 days. An oral glucose tolerance test was performed at the end of the experimental period. The concentration of short-chain fatty acids (SCFAs) in the cecum was analyzed by GC-MS (gas chromatography-mass spectrometry). The mRNA expression levels related to L cell function in the ileum were measured by real-time PCR. Glucagon-like peptide-1 (GLP-1) levels in the portal vein and cecal content were assessed by enzyme-linked immunosorbent assay. GLP-1-producing L cells of the ileum were quantified by immunohistochemistry. HGB intake improved glucose tolerance and increased the cecal levels of SCFAs, acetate, and propionate. The number of GLP-1-positive L cells in the HGB group was significantly higher than in the control group. GLP-1 levels in the portal vein and cecal GLP-1 pool size in the HGB group were significantly higher than the control group. In conclusion, we report improved glucose tolerance after HGB intake induced by an increase in L cell number and subsequent rise in GLP-1 secretion.

Coleus forskohlii Extract Attenuated the Beneficial Effect of Diet-Treatment on NASH in Mouse Model.

Obesity is one of the main causes of non-alcoholic steatohepatitis (NASH), which is associated with impaired liver functions including drug metabolism. Coleus forskohlii extract (CFE) is a popular ingredient of weight loss dietary supplements in Japan. In this study, we examined the effect of CFE on the treatment of NASH. C57BL/6 mice (male, 10-wk-old) were fed a NASH diet (high-fat, low-methionine, and choline-deficient diet) for 12 wk to establish NASH. Then, we examined the effect of 0.5% (w/w) CFE in diet during diet-treatment (change to control diet) and/or treadmill-exercise (45 min at 20 m/min, 5 d/wk) to improve NASH for 3 wk. After experimental period, lipids profiles and liver functional markers in the blood, and hepatic lipid content and major CYP subtype mRNA expression and activity in liver were measured. Diet-treatment, but not exercise decreased liver weight and hepatic lipid contents in NASH induced mice. CFE attenuated the effects of diet-treatment which reduced liver weight, even though body weight and adipose tissue weight were reduced. Further, CFE significantly increased liver microsomal CYP1A1, CYP1A2, CYP2C, and CYP3A activities in each condition, and CYP inductions were greater in diet-treatment group compared to those in exercise group. These results suggest that taking CFE should be avoided during diet-treatment of NASH, especially in patients under medication.

Diet-induced non-alcoholic fatty liver disease affects expression of major cytochrome P450 genes in a mouse model.

OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) is associated with impaired liver function, and resveratrol could suppress NAFLD progression. This study examined the effects of NAFLD on the expression of major cytochrome P450 (CYP) subtypes in the liver and whether the expression could be attenuated by resveratrol. METHODS: C57BL/6 mice (male, 10 weeks of age) were fed a high-fat and high-sucrose (HFHS) diet to induce NAFLD. Major Cyp subtype mRNA expression in the liver was measured by real-time RT-PCR. KEY FINDINGS: Body and liver weights at 4 and 12 weeks were significantly higher in mice fed the HFHS diet compared with control. The HFHS diet significantly increased the accumulation of cholesterol and triglycerides at 12 weeks. Under this condition, the HFHS diet increased the expression of Cyp1a2 and decreased that of Cyp3a11 at 1 week and thereafter. On the other hand, Cyp1a1, 2b10 and 2c29 mRNA expression levels in the liver were significantly increased at 12 weeks only. Resveratrol (0.05% (w/w) in diet) slightly suppressed lipid accumulation in the liver, but failed to recover impaired Cyp gene expression levels in NAFLD. CONCLUSIONS: Drug metabolism may be impaired in NAFLD, and each Cyp subtype is regulated in a different manner.

Evaluation of Methionine Content in a High-Fat and Choline-Deficient Diet on Body Weight Gain and the Development of Non-Alcoholic Steatohepatitis in Mice.

AIM: Non-alcoholic steatohepatitis (NASH) is a globally recognized liver disease. A methionine- and choline-deficient diet is used to induce NASH in mice; however, this diet also causes severe body weight loss. To resolve this issue, we examined the effects of methionine content in a high-fat and choline-deficient (HFCD) diet on body weight and the development of NASH in mice. METHODS: C57BL/6J mice (male, 10 weeks of age) were fed an L-amino acid rodent (control) diet, high-fat (HF) diet, or HFCD diet containing various amounts of methionine (0.1-0.6% (w/w)) for 12 weeks. Plasma lipid levels, hepatic lipid content and inflammatory marker gene expression were measured, and a pathological analysis was conducted to evaluate NASH. RESULTS: The 0.1% methionine in HFCD diet suppressed body weight gain, which was lower than that with control diet. On the other hand, the 0.2% methionine in HFCD diet yielded similar body weight gains as the control diet, while more than 0.4% methionine showed the same body weight gains as the HF diet. Liver weights and hepatic lipid contents were the greatest with 0.1% methionine and decreased in a methionine dose-dependent manner. Pathological analysis, NAFLD activity scores and gene expression levels in the liver revealed that 0.1% and 0.2% methionine for 12 weeks induced NASH, whereas 0.4% and 0.6% methionine attenuated the induction of NASH by HFCD diet. However, the 0.2% methionine in HFCD diet did not induce insulin resistance, despite the body weight gain. CONCLUSIONS: The 0.2% methionine in HFCD diet for 12 weeks was able to induce NASH without weight loss.

Influence of High-fat and High-cholesterol Diet on Major CYP Activities in the Liver.

We previously reported that a high-fat and high-cholesterol (HFHC) diet for 12 weeks induced non-alcoholic steatohepatitis (NASH) and influenced major CYP subtype gene expression levels and activities in a mouse model. In the present study, we determined the effects of the HFHC diet on CYP expression levels and activities prior to the establishment of NASH. When male C57BL/6J mice were fed the HFHC or a normal chow diet (Control) ad libitum for 4 weeks, body weights were significantly lower, whereas liver weights and hepatic lipid contents were significantly higher in the HFHC group than in the Control group. Under these conditions, hepatic microsomal luciferin-H (human CYP2C9 substrate) hydroxylation activity was significantly lower in the HFHC group than in the Control group. In order to investigate drug efficacy in mice fed the HFHC diet, an intraperitoneal glucose tolerance test was conducted with or without a pretreatment with tolbutamide (a CYP2C substrate) after 4 weeks of feeding. The plasma glucose-lowering effects of tolbutamide were attenuated in the HFHC group even though luciferin-H hydroxylation activity was suppressed in this group. The reason for this discrepancy was attributed to the mRNA expression levels of Cyp2c44 being lower and those of Cyp2c29 and Cyp2c66, which are involved in the metabolism of tolbutamide, being higher in the HFHC group than in the Control group. These results indicate that the expression of Cyp2c in the liver is influenced by the HFHC diet prior to the establishment of NASH and its regulation differed among the subtypes examined.

Factors Associated with Dietary Supplement Use among Preschool Children: Results from a Nationwide Survey in Japan.

This study was performed to reveal factors associated with dietary supplement use among Japanese preschool children in a nationwide survey. A cross-sectional, Internet survey was conducted among 2,058 mothers aged 20-40 y old who had preschool children and were registrants of a Japanese social research company in February 2013. The questionnaires assessed dietary supplement use, lifestyle and eating habits in both children and their mothers, eating awareness among mothers and the mothers' sources of health information. The study employed logistic regression analysis to evaluate the association between dietary supplement use and other variables. Dietary supplements were used by 8.0% of the children. Children who used supplements tended to be older in age, less likely to "get up cheerfully every morning," more likely to skip breakfast, eat out more frequently, and have mothers who used supplements, than children who did not use supplements. Mothers' level of education and household income were not associated with supplement use among their children. It is likely that mothers' anxiety about their children's health or unhealthy eating habits has a striking effect on supplement use among children. However, the actual dietary balance and daily rhythms of child supplement users were not irregular or unhealthy. It is necessary to give more accurate information on children's dietary habits and health to address mothers' anxiety.

Trans-Resveratrol Enhances the Anticoagulant Activity of Warfarin in a Mouse Model.

AIM: Resveratrol is a popular ingredient in dietary supplements. Some patients concomitantly use dietary supplements and medicines in Japan. In the present study, we determined whether trans-resveratrol and melinjo (Gnetum gnemon L.) seed extract (MSE), which contains resveratrol dimers, interacted with drugs using a mouse model. METHODS: Male C57BL/6J mice were fed experimental diets containing 0.005%, 0.05%, or 0.5% (w/w) trans-resveratrol or MSE for 1 or 12 weeks. The expression of liver cytochrome P-450 (CYP) mRNA and activity of liver microsomal CYP were measured. To determine the influence of resveratrol or MSE on drug efficacy, the anticoagulant activity of warfarin was examined in mice that were fed diets containing trans-resveratrol or MSE for 12 weeks. RESULTS: When the mice were fed experimental diets for 1 week, none of the doses of trans-resveratrol and MSE affected body weight, liver weight, or plasma AST and ALT levels. Trans-resveratrol also did not affect CYP1A1, CYP1A2, CYP2C, or CYP3A activities. In contrast, 0.5% MSE slightly increased CYP1A1 activity. When the mice were fed experimental diets for 12 weeks, 0.05% trans-resveratrol increased CYP1A1, CYP2C, and CYP3A activities, whereas 0.5% MSE suppressed CYP3A activity. Under these conditions, 0.5% trans-resveratrol enhanced the anticoagulant activity of warfarin, although CYP2C activity increased. However, MSE did not affect the anticoagulant activity of warfarin. CONCLUSION: The 0.05% trans-resveratrol did not interact with warfarin in a mouse model, whereas 0.5% trans-resveratrol may have enhanced the anticoagulant activity of warfarin.

Concomitant use of dietary supplements and medicines in patients due to miscommunication with physicians in Japan.

We previously reported that some patients used dietary supplements with their medication without consulting with physicians. Dietary supplements and medicines may interact with each other when used concomitantly, resulting in health problems. An Internet survey was conducted on 2109 people who concomitantly took dietary supplements and medicines in order to address dietary supplement usage in people who regularly take medicines in Japan. A total of 1508 patients (two admitted patients and 1506 ambulatory patients) and 601 non-patients, who were not consulting with physicians, participated in this study. Purpose for dietary supplement use was different among ages. Dietary supplements were used to treat diseases in 4.0% of non-patients and 11.9% of patients, while 10.8% of patients used dietary supplements to treat the same diseases as their medication. However, 70.3% of patients did not declare dietary supplement use to their physicians or pharmacists because they considered the concomitant use of dietary supplements and medicines to be safe. A total of 8.4% of all subjects realized the potential for adverse effects associated with dietary supplements. The incidence of adverse events was higher in patients who used dietary supplements to treat their disease. Communication between patients and physicians is important for avoiding the adverse effects associated with the concomitant use of dietary supplements and medicines.

Resveratrol Partially Suppresses Inflammatory Events but Does not Affect Stroke Onset in Stroke-Prone Spontaneously Hypertensive Rats.

AIM: Resveratrol has been shown to mimic the beneficial effects of dietary restriction (DR). We previously reported that DR delays stroke onset and extends the lifespan in Stroke-Prone Spontaneously Hypertensive rats (SHRSP). Therefore, we examined whether resveratrol mimics DR and delays stroke onset in SHRSP. METHODS: Cerebrovascular endothelial cells (CVECs) from SHRSP were treated with resveratrol, and the inflammatory gene expression levels and NFκB protein levels were measured. In order to address the effects of resveratrol in vivo, SHRSP (male, 10 weeks of age) were fed an experimental diet containing several doses of resveratrol (0 - 0.05% (w/w)), after which we measured the plasma cytokine levels and examined the stroke onset and lifespan. RESULTS: Treatment with resveratrol (100 µM, 24 hours) in CVECs from SHRSP significantly decreased the interleukin (IL)-1ß-induced monocyte chemoattractant protein-1 (MCP-1) mRNA expression levels and p50 and p65 protein levels in the nuclear fraction. When the SHRSP were fed a diet containing resveratrol for one week, the resveratrol treatment did not affect the plasma lipid and glucose levels, body weight or weight of each tissue. Resveratrol slightly, but not significantly, decreased the plasma levels of IL-1ß and MCP-1 compared with that observed in the control group. In addition, resveratrol decreased the IL-1ß and MCP-1 mRNA expression levels in the brain versus the control animals. However, no doses of resveratrol delayed stroke onset or extended the lifespan in SHRSP. CONCLUSIONS: In this study, resveratrol did not delay stroke onset in SHRSP, although it partially suppressed systemic and cerebral inflammation. These results suggest that resveratrol does not mimic the beneficial effects of DR on stroke in vivo.

Inappropriate usage of dietary supplements in patients by miscommunication with physicians in Japan.

Recently, people have used dietary supplements not only for nutritional supplementation, but also for treatment of their diseases. However, use of dietary supplements to treat diseases, especially with medications, may cause health problems in patients. In this study, we investigated use of dietary supplements in patients in Japan. This survey was conducted from January to December 2012, and was completed by 2732 people, including 599 admitted patients, 1154 ambulatory patients, and 979 healthy subjects who attended a seminar about dietary supplements. At the time of the questionnaire, 20.4% of admitted patients, 39.1% of ambulatory patients, and 30.7% of healthy subjects were using dietary supplements, which including vitamin/mineral supplements, herbal extracts, its ingredients, or food for specified health uses. The primary purpose for use in all groups was health maintenance, whereas 3.7% of healthy subjects, 10.0% of ambulatory patients, and 13.2% of admitted patients used dietary supplements to treat diseases. In addition, 17.7% of admitted patients and 36.8% of ambulatory patients were using dietary supplements concomitantly with their medications. However, among both admitted patients and ambulatory patients, almost 70% did not mention dietary supplement use to their physicians. Overall, 3.3% of all subjects realized adverse effects associated with dietary supplements. Communication between patients and physicians is important to avoid health problems associated with the use of dietary supplements.