Journal of nutritional science and vitaminology最新文献

Bitterness and astringency are the aversive tastes in mammals. In humans, aversion to bitterness and astringency may be reduced depending on the eating experience. However, the cellular and molecular mechanisms underlying plasticity in preference to bitter and astringent tastants remain unknown. This study aimed to investigate the preference plasticity to bitter and astringent tea polyphenols, including catechins and tannic acids, in the model animal Caenorhabditis elegans. C. elegans showed avoidance behavior against epigallocatechin gallate (EGCG), tannic acid, and theaflavin. However, they displayed diminishing avoidance against EGCG depending on their EGCG-feeding regime at larval stages. Additionally, the behavioral plasticity in avoiding EGCG required the transcription factor DAF-16/FOXO. Isoform-specific deletion mutant analysis and cell-specific rescue analysis revealed that the function of daf-16 isoform b in AIY interneurons is necessary for experience-dependent behavioral plasticity to EGCG.

This randomized controlled clinical study aimed to assess the effectiveness of a nutrition intervention program for non-pregnant female workers in Vietnam. A total of 500 female workers were randomly assigned to the intervention and control groups. Participants in the intervention group were provided nutrition education, personalized specific dietary, and received oral nutrition supplements (ONS)-which contained multi-minerals and vitamins according to recommendations for adults for a duration of 12 wk, while participants in the control group received only nutrition education. The result shows the percentage of malnutrition by BMI in the control group rose from 15.6% to 21.3% after 12 wk; the figure for counterpart experienced a remain unchanged (p<0.05). Additionally, the mean of serum zinc in the intervention group significantly increased from 49.0±21.2 μg/dL to 53.6±19.5 μg/dL after 12 wk. Moreover, the intervention group demonstrated significant increases in serum iron and total serum calcium levels (p<0.05), with from 13.9±5.6 μmol/L to 15.3±5.8 μmol/L, and from 2.36±0.15 mmol/L to 2.4±0.09 mmol/L, respectively. The participants of the intervention group were more likely to have higher total serum calcium (Coef=0.04, p<0.05), serum iron (Coef=1.99, p<0.05), and serum zinc (Coef=18.9, p<0.05), which presents a reduce micronutrient deficiency. In conclusion, workplace nutrition interventions effectively mitigate micronutrient deficiencies and improve the nutritional status of female workers.

Pyridoxamine (PM) is one of the natural vitamins B6 (VB6) and functions as an endogenous inhibitor for the formation of AGEs (advanced glycation end products). The AGEs are implicated in aging, diabetes, and various neuropsychiatric disease, including schizophrenia, Alzheimer's disease, and Parkinson's disease. However, it is unclear whether the absence of PM per se accumulates AGEs in vivo and causes behavioral dysfunctions. To address these points, we raised PM-deficient fruit flies, Drosophila melanogaster, with the sterilized defined medium. Flies reared in a PM-deficient medium accumulated AGEs and reduced lifespan, impaired gustatory response, sleep, courtship behavior, and olfactory learning. These results suggest that PM suppresses AGE accumulation in vivo and is required for regulating innate and empirical behaviors.

Since propionate exerts several physiological effects, maintenance of its normal colonic fermentation is essential. To investigate whether vitamin B₁₂ (VB₁₂) is essential for normal propionate fermentation by colonic bacteria, via the succinate pathway, we examined if high-amylose cornstarch (HACS) feeding activated such a pathway, if high HACS feeding impaired propionate fermentation, and if oral VB₁₂ supplementation normalized propionate fermentation. Male rats were given control, 20% HACS or 3% fucose diets (Expt. 1); a VB₁₂-free control diet or one supplemented with 5-30% HACS (Expt. 2); and the 20% HACS diet supplemented with 0.025-25 mg/kg of VB₁₂ (Expt. 3), for 14 d. HACS feeding significantly increased cecal succinate concentration, activating the succinate pathway (Expt. 1). Cecal cobalamin concentration in 20% and 30% HACS groups was about 75% of that in the control group (Expt. 2). Cecal succinate and propionate concentrations significantly increased and decreased in 30% HACS groups, respectively, compared with the control group. Although HACS group supplemented with 0.025 mg/kg of VB₁₂ had a low concentration of cecal propionate, adding high amounts of VB₁₂ to HACS diets provided sufficient amounts of VB₁₂ to rat ceca and increased cecal propionate concentration (Expt. 3). Compared with the non-HACS group, the relative abundance of Akkermansia muciniphila, but not Bacteroides/Phocaeicola, was lower in the HACS counterpart and showed improvement with increased VB₁₂ doses. To summarize, feeding high HACS decreased and increased cecal VB₁₂ and succinate concentrations, respectively. Furthermore, colonic delivery of sufficient amounts of VB₁₂ to rats likely reduced accumulation of succinate and normalized propionate fermentation.

The composition of gut microbiota is determined not only by genetic factors but also by environmental factors, such as diet, exercise, and disease conditions. Among these factors, diet is crucial in changing the gut microbial composition. Dietary lipids composed of different fatty acids not only alter host metabolism but also have a significant impact on the composition of gut microbiota. However, the molecular mechanisms underlying the relationship between these host effects and their impact on gut microbiota remain unclear. Here, we demonstrated that intake of different dietary lipids improved glucose tolerance by modulating gut microbiota. The results of our analysis show that the taxa of bacteria that increase in number as a result of dietary lipid intake play an important role in glucose metabolism. Thus, we have identified a new mechanism underlying the function of dietary lipids in regulating glucose homeostasis. Our findings contribute to possible new methods to prevent and treat metabolic disorders by modifying the composition of gut microbiota.

A 76-item food frequency questionnaire (FFQ) was developed to investigate nutritional epidemiology in urban residents in Japan. The authors prepared two food models-a life-size three-dimensional model and a life-size two-dimensional photograph-to assess the FFQ portion size. The validity of the FFQ was verified using the two food models by comparing them with 16-d weighted dietary records (WDRs). Validation was conducted by comparing the FFQ1 findings with those obtained with the WDR, which is regarded as the gold standard, and reproducibility was verified by comparing the findings from FFQ2 and FFQ1. After completion of the WDR, the participants were randomized into two groups. In one group, the FFQ was conducted using life-size three-dimensional models (3D-FFQ) to estimate the portion size. In the other group, the FFQ was administered using life-size photo collection (2D-FFQ). Regarding validity, the median values (range) of Pearson's correlation coefficients for the energy and nutrient intake of the 32 items by the WDR and FFQ1 were r=0.53 (0.30-0.68) in the 3D-FFQ and r=0.57 (0.33-0.87) in the 2D-FFQ. When FFQs with 2D or 3D food models and two different portion sizes were compared with regard to the intake of certain food groups, energy, and nutrients, both the 2D-FFQ and 3D-FFQ provided good correlation coefficients with the WDR.

To ascertain whether habitual green tea consumption is associated with sarcopenia among Japanese older adults, using the screening tool for sarcopenia (SARC-F). This cross-sectional study in Mukawa, Hokkaido, Japan, was conducted between June and September 2022 and included 364 Japanese participants older than 65 y. Habitual green tea consumption and energy intake were ascertained using a validated self-administered food frequency questionnaire. Sarcopenia was evaluated using the SARC-F. Multivariable logistic regression analysis was used to estimate the odds ratio (OR) and 95% confidence interval (CI) of sarcopenia risk across participant tertiles of green tea consumption, with adjustments for age, sex, body mass index, living alone, habitual exercise, walking hours, current smoking status, current alcohol consumption status, energy intake, protein intake, vegetable intake, and fruit intake. In this study of 364 participants (154 men and 210 women), the prevalence of sarcopenia risk was 9.3%. The multivariable-adjusted OR [95% CI] of green tea consumption for ≥1 cup/d compared with that of <1 cup/wk of sarcopenia was 0.312 [0.129-0.752]. Higher habitual green tea consumption was inversely associated with sarcopenia among Japanese older adults. Further longitudinal studies are required to confirm these findings.

Dairy products formulated with bioactives are widely distributed in Japan, but it remains to be clear whether a regular consumption of these products would help reduce the risks of incidental functional disability and dementia in older adults. This study aimed to investigate Japanese subjects aged ≥65 y (n=629) that routinely consumed three functional dairy products, a calcium-enriched milk supplemented with Bifidobacterium longum BB536, a yogurt supplemented with lactoferrin, B. longum BB536 and heat-killed Lacticaseibacillus paracasei MCC1849, and a drinkable yogurt supplemented with lactoferrin, B. longum BB536 and heat-killed L. paracasei MCC1849, through a home delivery service. Intake frequency and intake duration of these functional dairy products were compared with the risk scores of incident functional disability and dementia, developed by the Japan Gerontological Evaluation Study. In the participants aged <75 y, the incident functional disability risk was significantly maintained or decreased in the participants with the long intake duration level compared with the short intake duration level (OR, 95% CI: 0.48, 0.25-0.93). In the participants aged ≥75 y, the dementia risk was significantly maintained or decreased in the participants with the high intake frequency level compared with the low intake frequency level (OR, 95% CI: 0.46, 0.22-0.95). A high intake frequency or long term duration of these functional dairy products may be effective in preventing an aging-related increase in the risks of incident functional disability and dementia in older adults, but this warrants further investigation using different products containing different bioactives.

In this study, we investigated the effects of a porcine liver protein hydrolysate (PLH) diet on lipid metabolism in Otsuka Long-Evans Tokushima Fatty (OLETF) rats, a model of type II diabetes. OLETF rats (20-wk-old males) were pair-fed with either a PLH diet containing 20% PLH or a casein diet for 14 wk. Dietary PLH significantly lowered serum cholesterol and phospholipid concentrations, mainly by decreasing low-density lipoprotein and high-density lipoprotein fractions. Fecal cholesterol was significantly increased in the PLH diet group; however, the total bile acid concentration in the feces was not significantly different between the groups. In addition, the PLH diet significantly decreased serum thiobarbituric acid reactive substance concentrations. These results suggest that dietary PLH exerts hyperlipidemic and antioxidant effects, indicating that it is a novel functional food ingredient.

The major characteristic of type 2 diabetes is insulin resistance, which is associated with plasma level of 12-hydroxylated bile acids (BAs) in humans. In this study, we investigated whether the rise of enterohepatic 12-hydroxylated BAs associates with glucose tolerance and/or insulin secretion using rats fed a diet supplemented with cholic acid (CA) at a level of 0.5 g/kg diet. Almost no increase was observed in plasma insulin in response to the intraperitoneal glucose administration in the CA-fed rats despite the significant increase of plasma insulin in control with the same treatment. In contrast, the changes in insulin secretion were observed in both groups and no difference was detected between the groups in the oral glucose tolerance test. Increases were observed in pancreatic expressions of Ins1 and Ins2 although the insulin protein content decreased in the pancreas without any sign in ectopic fat accumulation and histological damage in the CA-fed rats. Our results suggest that enterohepatic 12-hydroxylated BAs modulate insulin secretion in response to intraperitoneal glucose administration. The decrease in insulin store might be responsible for the reduction in the insulin secretion in the CA-fed rats.