International Journal for Vitamin and Nutrition Research最新文献

Background: It is now becoming increasingly recognized that the effects of vitamin D supplementation may vary by several factors including vitamin D deficiency status, ethnicity, and/or the presence of genetic variants, which affect individual responses to supplementation. This study investigates the interaction between metabolic traits and circulating 25-hydroxyvitamin-D (25OHD) concentration with 4 polymorphisms of vitamin D receptor (VDR) including BsmI, ApaI, TaqI, FokI, and vitamin D supplementation. Methods: A systematic review and meta-analysis of papers until August 2021 on PubMed, The Cochrane Library, Scopus, Web of Science, Google Scholar, ProQuest, Science Direct, and Embase about the association between functionally relevant VDR variants and vitamin D supplementation on circulating 25OHD and metabolic traits. Results: A total of 2994 cases from 16 randomized controlled trial (RCT) studies were included in meta-analyses. There were no significant changes in the serum concentrations of 25OHD and metabolic traits after vitamin D supplementation in different variants of BsmI, ApaI, TaqI, and FokI polymorphism in the VDR gene in the overall analysis (p>0.05). However, the results showed there is significant interaction between these above VDR polymorphisms and vitamin D supplement on serum 25OHD level after subgroup analyses based on the study duration, gender, age, BMI, health status, Hardy-Weinberg Equilibrium, PCR, and race (p<0.05). Conclusions: The present meta-analysis demonstrates that the effect of vitamin D supplementation on serum 25OHD and metabolic traits is independent of genetic variants of the VDR gene (BsmI, ApaI, TaqI, and FokI). However, future trials should consider inter-individual differences and, in particular, should aim to clarify whether certain subgroups of individuals may benefit from vitamin D supplementation in the context of metabolic health.

Objective(s): Cardio-metabolic risk factors are becoming a global health concern. To address this problem, one of the proposed ways is to focus on phytochemical-rich foods consumption. Therefore, we aimed to summarize the results of observational studies (cohorts, case-control, and cross-sectional) that investigated the association between dietary phytochemical index (PI) as a new index for evaluating phytochemical-rich food intake and various risk factors of cardio-metabolic disorders. Methods: We conducted a comprehensive systematic review through PubMed, Scopus, and Web of Science databases. The literature search was performed up to August 2021 with no publication year restriction on observational studies investigating the association between PI and cardiometabolic risk factors on adults and children. A random-effect meta-analysis was used. Results: Overall, 16 articles (cross-sectional, case-control, cohort) were eligible for this systematic review and 8 studies with 99771 participants were included in the meta-analysis. Random effect meta-analysis showed that adherence to higher dietary PI decrease the odds of abdominal obesity (OR: 0.73, 95% CI: 0.58, 0.88, I²: 84.90), generalized obesity (OR: 0.84, 95% CI: 0.69, 0.98, I²: 68.10), hypertriglyceridemia (OR: 0.81, 95% CI: 0.73, 0.89, I²: 0.00), hypertension (OR: 0.86, 95% CI: 0.73, 0.99, I²: 7.02), and MetS (OR: 0.79, 95% CI: 0.69, 0.88, I²: 84.90). However, results considering the associations between dietary PI with glycemic indices, and low high-density lipoprotein cholesterol (HDL-C) were not significant (p<0.05). Conclusion: Evidence showed adverse associations between dietary PI and some cardio-metabolic risk factors such as obesity, hypertriglyceridemia, hypertension and metabolic syndrome.

Background: Despite advances in prevention and treatment, colorectal cancer remains the second most common cause of cancer death. To date, little is known about the role of prediagnostic selenium intake in colorectal cancer survival. Objective: The purpose of the study was to verify whether selenium intake in habitual diet before diagnosis is associated with survival in colorectal cancer patients. Study design: This was a prospective observation of patients primarily recruited for a case-control study between 2000 and 2012 in Cracow, Poland. A group of 671 incident cases of colorectal cancer was included. Habitual diet was assessed using a validated 148-item food questionnaire. 338 deaths were identified throughout 2017 by the Polish National Vital Registry. To evaluate the impact of dietary selenium on survival, the multivariable Cox regression model was used. Results: After standardization for several potential confounders (including key determinants, such as radical surgery, chemotherapy, tumor stage, and dietary factors), a decrease in the risk of death from colorectal cancer was observed in the group with higher dietary selenium intake (≥48.8 μg/day, group mean: 63.9 μg/day) compared to the group with lower dietary selenium intake (<48.8 μg/day, mean: 38.5 μg/day) (HR=0.73; 95% CI: 0.54-0.98) (the median was used for categorization). Conclusion: Our study suggests selenium as an additional dietary factor which may be associated with survival among colorectal cancer patients referred to surgery. Due to the observational nature of the study, the results should be taken with caution. These preliminary findings, however, provide the basis for well-structured clinical trials.

We aimed to assess the effects of omega fatty acids on time depending on responses of satiety hormones. Sixty adult rats were randomly divided into 4 groups; linoleic acid (LA), α-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) groups. For each fatty acid, the dose of 400 mg/kg was applied by oral gavage. Blood samples were taken after the 15, 30, 60 and 120 minutes. Ghrelin, cholecystokinin (CCK), glucagon-like peptide-1 (GLP-1), peptide YY (PYY), leptin and insulin hormones were analyzed by ELISA. We observed the significant increases (p<0.05) of the levels of CCK between n-3 (ALA, at 60^th min; EPA, at 30^th and 60^th min and DHA, at 60 min) and n-6 (LA) supplemented rats. The highest GLP-1 levels were in ALA (0.70 ng/mL) and DHA (0.67 ng/mL) supplemented groups at 60^th and 120^th min indicating n-3 fatty acids efficiency on satiety compared to LA. It seems that ALA at 60^th min and EPA at 120^th min could provide the highest satiety effect with the highest insulin response, while the efficiency of LA supplementation on insulin-induced satiety diminished. The only significant change in AUC values among all hormones was in the CCK of the ALA group (p=0.004). The level of leptin increased in DHA and EPA supplemented rats (p=0.140). Our results showed that dietary omega fatty acids influenced the releasing of hormones in different ways possibly depending on chain length or saturation degree. Comprehensive studies need to be addressed for each fatty acid on satiety-related peptide hormones.

Gut microbiota and short-chain fatty acids (SCFAs) are recognized as key factors in the pathophysiology of irritable bowel syndrome. Astaxanthin is a carotenoid with strong antioxidant and anti-inflammatory activities. In this study, we examined the effects of astaxanthin on gut microbiota-, SCFAs-, and corticotropin-releasing factor (CRH)-induced intestinal hypermotility. Male Wistar rats (n=12 per group) were fed a diet with or without 0. 02% (w/w) astaxanthin for four weeks and CRH or saline was administered intravenously. The number of fecal pellets was counted 2 h after injection. Then the rats were sacrificed, and the cecal content were collected 3 h after injection. The number of feces was significantly increased by CRH injection in the control group (2.0 vs. 6.5; p=0.028), but not in the astaxanthin group (1.0 vs. 2.2; p=0.229) (n=6 per group). The cecal microbiota in the astaxanthin group was significantly altered compared with that in the control group. The concentrations of acetic acid (81.1 μmol/g vs. 103.9 μmol/g; p=0.015) and butyric acid (13.4 μmol/g vs. 39.2 μmol/g; p<0.001) in the astaxanthin group were significantly lower than that in the control group (n=12 per group). Astaxanthin attenuates CRH-induced intestinal hypermotility and alters the composition of gut microbiota and SCFAs.

Several pre-workout supplements contain niacin, although the exercise performance effects of niacin are poorly understood. The purpose of the present study was to examine the performance effects of niacin versus caffeine as a pre-workout supplement. Twenty-five untrained males were recruited to complete three identical ramped aerobic cycling exercise trials. Participants were administered caffeine (CA) at 5 mg/kg body weight, 1000 mg niacin (NI), or a methylcelluloce placebo (PL) supplement prior to each trial. NI treatment induced significantly higher respiratory exchange ratio (RER) during exercise compared to the CA treatment, but not the PL treatment (PL=0.87±0.08, NI=0.91±0.08, CA=0.87±0.08; p=0.02). Similarly, exercise time to exhaustion (in minutes) was significantly different between the NI treatment and the CA treatment, but not the PL treatment (PL=27.45±4.47, NI=26.30±4.91, CA=28.76±4.86; p<0.01). Habitual caffeine use (p=0.16), habitual aerobic exercise (p=0.60), and habitual resistance exercise (p=0.10) did not significantly affect RER. Similarly, habitual caffeine use (p=0.72), habitual aerobic exercise (p=0.08), and habitual resistance exercise (p=0.39) did not significantly affect total work performed. The elevated RER and decreased time to exhaustion in the NI treatment suggests limited lipid availability during exercise and impaired exercise performance.

Objectives: To determine whether SNPs of osteoarthritis (OA)-related genes predict the effect of Chrysanthemum zawadskii var. latilobum (CZ) extract in OA patients with OA. Subjects/methods: To analyze correlations between CZ extract effects in humans and their genotypes, 121 Korean patients with OA were recruited. Patients ingested 600 mg/day of the CZ extract GCWB106 (one tablet daily), including 250-mg CZ, or placebo (one tablet daily) for 12 weeks. Twenty SNPs were genotyped in 11 genes associated with OA pathogenesis, including tumor necrosis factor-alpha (TNF-α) and matrix metalloproteinases (MMPs), and 9 genes involved in OA-related dietary intervention. The Visual Analogue Scale (VAS) and Korean Western Ontario and McMaster Universities (K-WOMAC) were measured as indicators of GCWB106 effect. Statistical comparisons were performed using Kruskal-Wallis tests to identify associations between these scales and genotyped loci in patients with OA. Results: Three SNPs (PPARG rs3856806, MMP13 rs2252070, and ZIP2 rs2234632) were significantly associated with the degree of change in VAS pain score. Homozygous CC genotype carriers of rs3856806, G allele carriers (GA or GG) of rs2252070, and T allele carriers (GT or TT) of rs2234632 showed lower VAS score (i.e., less severe symptoms) in the GCWB106 group (n=53) than the placebo group (n=57) (p=0.026, p=0.009, and p=0.025, respectively). Gene-gene interaction effects on GCWB106-mediated pain relief were then examined, and it was found that the addition of each genotype resulted in a greater decrease in VAS pain score in the GCWB106 group (p=0.0024) but not the placebo group (p=0.7734). Conclusions: These novel predictive markers for the pain-relieving effects of GCWB106 may be used in the personalized treatment of patients with OA.

High dietary sodium and low potassium intake is associated with high blood pressure (BP). The current study aimed to determine if the sodium-to-potassium ratio is more strongly associated with low (130-139/80-89 mm Hg) and high (≥140/90 mm Hg) BP thresholds among US adults than either sodium or potassium alone. A total of 30,776 patients aged ≥20 years with complete blood pressure participated in the National Health and Nutrition Examination Survey (NHANES) from 2003 to 2018. Demographic information and health characteristics were compared between men and women using the chi-square test for categorical variables and independent samples t-test for continuous variables. Logistic regression was performed to investigate the association of the odds ratios (OR) of different levels of sodium, potassium, and sodium-to-potassium ratio. After multivariable adjustment (age, gender, Body mass index, Smoking, education, Race, Alcohol, total energy intake, and physical activity), no relationship has been observed between high versus low sodium-to-potassium ratio and BP threshold of 130-139/80-89 mm Hg (odds ratio [OR]: 1.02, 95% confidence interval [CI]: 0.92-1.12). Higher sodium-to-potassium ratio (OR=1.24; CI: 1.11-1.38) and dietary intake of potassium (OR=0.66; CI: 0.55-0.80) showed significant association in reducing the BP threshold of ≥140/90 mm Hg. In dose-response analysis, higher BP ≥140/90 mm Hg was inversely associated with higher potassium intake. Furthermore, the sodium-to-potassium ratio showed higher odds in predicting the BP of patients aged ≤60 years, underweight, nonsmokers, and non-alcohol users. The study confirms an inverse association between higher potassium intake and higher BP threshold. The Doses-response analyses showed sodium-to-potassium ratio is a better predictor of BP thresholds than sodium or potassium alone.

New evidence suggests that soy products might reduce chronic systemic inflammation. Therefore, we aimed to summarize the effect of soy isoflavones on serum concentration of C-reactive protein (CRP) among participants with chronic inflammatory disorders by conducting this study. Cochrane Library, Scopus, ISI Web of Science, clinicaltrials.gov, and PubMed were searched to identify randomized clinical trials (RCTs) published up to December 2020. The effect size was calculated by the mean change from baseline in concentrations of CRP and its standard deviation for both intervention and comparison groups. DerSimonian and Laird random-effects model was used when the heterogeneity test was statistically significant. In total, thirteen RCTs involving 1213 participants and ten RCTs involving 1052 participants were eligible for our systematic review and meta-analysis respectively. Study duration ranged from 4 to 96 weeks and soy isoflavones dose varied from 33 to 132 mg/day. Overall effect size indicated a non-significant effect on serum concentration of CRP following soy isoflavones intake (weighted mean differences (WMD)=-0.15 mg/L, 95% confidence interval (CI): -0.54, 0.23; p=0.430). Subgroup analysis revealed that soy isoflavones significantly reduced serum concentration of CRP in studies among participants with age >57 years and baseline CRP levels >3.75 mg/L. The present study proposed that soy isoflavones could not significantly reduce serum CRP levels. It seems more RCTs on participants with age more than 57 years and higher levels of CRP is necessary.