The Acute Effect of a Novel Miso-Type Sauce, Enhanced with a Carotenoid-Rich Extract from Fruit By-Products, on Postprandial Biomarkers of Oxidative Stress and Inflammation.

Several fruit by-products may exert a beneficial role on oxidative stress and inflammation modulation, providing essential bioactive components, such as polyphenols and carotenoids. Recently, the potential bioactivity of miso has been reported. The aim of this dietary intervention−clinical study was to evaluate the acute effect of a novel, functional miso-type sauce based on legumes, on postprandial biomarkers of oxidative stress and inflammation. In this randomized, cross-over design, intervention−clinical trial, 14 healthy volunteers, aged 20−30 years old, consumed a rice meal rich in fat and carbohydrates (258 g), containing a legume-based sauce. After a 1-week washout period, the same subjects consumed the same meal, containing the novel fermented miso-type sauce, enhanced with 50% carotenoid-rich, fruit peel extract. Differences in postprandial total plasma antioxidant capacity according to the FRAP method, serum lipids, glucose, uric acid levels, and antithrombotic activity in platelet-rich plasma were evaluated before, 30 min, 1.5 h, and 3 h after consumption. The results showed that, in comparison to the control group, consumption of the novel sauce resulted in a significantly increased total plasma antioxidant capacity 3 h after consumption (p < 0.05). In addition, we observed a significant attenuation of triglycerides concentration increase in the last 1.5 h in the functional group (p < 0.05). A significant decrease in serum aggregation was found at 30 min and 3 h after functional sauce intake in comparison with the baseline (p < 0.05). Finally, LDL-cholesterol concentrations were significantly reduced 3 h after the functional meal consumption, in comparison with baseline values (p < 0.05). The remaining biomarkers did not show statistically significant differences (p > 0.05). Further investigation is needed in order to validate the current results.

Superinfection of hepatitis A virus in hepatocytes infected with hepatitis B virus.

Hepatitis A virus (HAV) infection is a major cause of acute hepatitis including acute liver failure. Hepatitis B infection (HBV) occurs worldwide, with the highest rates in Asian and African countries, and there are several reports that HAV infection may have a more severe clinical course in patients with chronic HBV infection. We previously demonstrated that Japanese miso extracts have inhibitory effects on HAV replication. In the present study, we examined the replication of HAV and HBV in a hepatocyte superinfection model and the inhibitory effects of Japanese miso extracts on both viruses. According to the results, HAV infection inhibited HBV replication in superinfected hepatocytes, and Japanese rice-koji miso extracts had inhibitory effects on HAV replication. Our findings provide useful information for clinicians in managing HAV infection in patients with chronic HBV infection.

Miso (Fermented Soybean Paste) Suppresses Visceral Fat Accumulation in Mice, Especially in Combination with Exercise.

We investigated whether the difference in miso consumption between the Japanese diets of 1975 and 2010 has influenced the observed increase in diet-induced obesity. To recreate the 2010 and 1975 Japanese high-fat diets with the corresponding proportions of miso, freeze-dried miso was added to high-fat mouse feed at 1.6% and 2.6%, respectively. When 5-week-old male Institute of Cancer Research (ICR) mice were provided each of these diets ad libitum for 8 weeks, it was found that the white adipose tissue weight and adipocyte area were lower in mice receiving the 1975 diet than in those receiving the 2010 diet. Therefore, high miso consumption is one reason why the 1975 Japanese diet tended to not lead to obesity. Next, the combined effects of treadmill exercise and miso consumption were investigated. The mice were divided into three groups, which were provided either a high-fat diet (group C), a high-fat diet with exercise (group C + E), or a miso-supplemented high-fat diet with exercise (group M + E) for 8 weeks. In this experiment, the white adipose tissue weight and adipocyte area in group M + E were lower than in group C. When the mRNA expression of lipid metabolism-associated genes in adipose tissue was measured, we found that expression of Hsl (lipase, hormone sensitive), which is involved in lipolysis, and Pparγ (peroxisome proliferator activated receptor gamma), which regulates adipocyte differentiation upstream of Hsl, was increased in group M + E. These results clearly demonstrated that lipid accumulation in the adipose tissues is suppressed by miso consumption in combination with exercise.

Inhibitory effect of Japanese rice-koji miso extracts on hepatitis A virus replication in association with the elevation of glucose-regulated protein 78 expression.

Hepatitis A virus (HAV) infection is one of the major causes of acute hepatitis and acute liver failure in developing and developed countries. Although effective vaccines for HAV infection are available, outbreaks of HAV infection still cause deaths, even in developed countries. One approach to control HAV infection is prevention through diet, which can inhibit HAV propagation and replication. Glucose-regulated protein 78 (GRP78) is a member of the heat shock protein 70 family of molecular chaperone required for endoplasmic reticulum stress and stress-induced autophagy. We previously showed that the elevation of GRP78 expression inhibits HAV replication. It has been reported that Japanese miso extracts, which was made from rice-koji, enhance GRP78 expression. In the present study, we used human hepatoma Huh7 cells and human hepatocyte PXB cells to examine the efficacy of Japanese miso extracts as antiviral agents against HAV. Japanese miso extracts enhanced GRP78 expression and inhibited HAV replication in human hepatocytes. Together, these results demonstrate that Japanese miso extracts may partly modulate GRP78 expression and additively or synergistically work as antivirals against HAV infection. Japanese miso extracts can be used as effective dietary supplements for severe hepatitis A.