Resveratrol, EGCG and Vitamins Modulate Activated T Lymphocytes.

Vitamins and bioactives, which are constituents of the food chain, modulate T lymphocyte proliferation and differentiation, antibody production, and prevent inflammation and autoimmunity. We investigated the effects of vitamins (vitamin A (VA), D (VD), E (VE)) and bioactives (i.e., resveratrol (Res), epigallocatechin-3-gallate (EGCG)) on the adaptive immune response, as well as their synergistic or antagonistic interactions. Freshly isolated T lymphocytes from healthy individuals were activated with anti-CD3/CD28 antibodies for 4-5 days in the presence of bioactives and were analyzed by cytofluorometry. Interleukins, cytokines, and chemokines were measured by multiple ELISA. Gene expression was measured by quantitative RT-PCR. Res and EGCG increased CD4 surface intensity. EGCG led to an increased proportion of CD8+ lymphocytes. Anti-CD3/CD28 activation induced exuberant secretion of interleukins and cytokines by T lymphocyte subsets. VD strongly enhanced Th2 cytokines (e.g., IL-5, IL-13), whereas Res and EGCG favored secretion of Th1 cytokines (e.g., IL-2, INF-γ). Res and VD mutually influenced cytokine production, but VD dominated the cytokine secretion pattern. The substances changed gene expression of interleukins and cytokines in a similar way as they did secretion. Collectively, VD strongly modulated cytokine and interleukin production and favored Th2 functions. Resveratrol and EGCG promoted the Th1 response. VA and VE had only a marginal effect, but they altered both Th1 and Th2 response. In vivo, bioactives might therefore interact with vitamins and support the outcome and extent of the adaptive immune response.

Effect of regioisomers of hydroxystearic acids as peroxisomal proliferator-activated receptor agonists to boost the anti-ageing potential of retinoids.

INTRODUCTION: We report on the in vitro and ex vivo effects of chiral (R)-10-hydroxystearic acid (10-HSA) compared with other mono-hydroxystearic acid regioisomers and stearic acid (SA) together with its benefit when combined with retinol. METHODS: Following treatment with hydroxystearic acids peroxisomal proliferator-activated receptor alpha (PPARα) activity was determined in a luciferase reporter gene assay, collagen type I was assessed in primary human dermal fibroblasts by immunohistochemistry, modification of the intracellular fibroblast collagen proteome was studied by mass-spectrometry-based proteomics and collagen type III was assessed by immunohistochemistry on human ex vivo skin. RESULTS: 10-HSA was the most effective PPARα agonist (15.7× induction; p < 0.001), followed by 9-HSA (10.1× induction) and then 12-HSA (4.9× induction) with 17-HSA (1.7× induction) being similar to the effects of stearic acid (1.8× induction). Collagen type I levels were increased in primary human fibroblasts by 2.12× and 1.56× for 10-HSA and 9-HSA, respectively, in vitro with the10-HSA being significant (p < 0.05), whereas 12-HSA and SA had no statistical effect over the untreated control. 10-HSA and 12-HSA modified the intracellular fibroblast collagen proteome slightly with significant increases in collagen alpha-1 (VI) and alpha-3 (VI) proteins but only 10-HSA increased levels of collagen alpha-2 (V), alpha-1 (III), alpha-1 (I) and alpha-2 (I) (all p < 0.05) with the increases being significantly different between 10-HSA and 12-HSA for collagen alpha-1 (I), collagen-3 (VI) and collagen alpha-2 (I) (p < 0.01). Collagen type III in ex vivo skin was increased +47% (p < 0.05) by 0.05% (1.7 mM) retinol, +70% (p < 0.01) by 0.01% (0.33 mM) 10-HSA and the combination increased levels by +240% (p < 0.01 for either ingredient). CONCLUSION: Chiral (R)-10-HSA has been shown to be superior to 9, 12 and 17-HSA as a PPARα agonist. Moreover, 10-HSA stimulated collagen synthesis in monolayer fibroblast culture as assessed by proteomics and immunohistochemically. Furthermore, we also show the synergistic effects of 10-HSA with retinol on collagen III synthesis in skin explants. These results further highlight the efficacy of 10-HSA as a cosmetically acceptable PPARα agonist and anti-ageing ingredient.

INTRODUCTION: Nous rapportons les effets in vitro et ex vivo de l'acide chiral (R)-10-hydroxystéarique (10-HSA) par rapport à d'autres régioisomères d'acide mono-hydroxystéarique et à l'acide stéarique (SA) ainsi que ses avantages lorsqu'il est associé au rétinol. MÉTHODES: Après un traitement avec des acides hydroxystéariques, l'activité du récepteur alpha activé par les proliférateurs peroxysomaux (PPARα) a été déterminée dans un test du gène rapporteur de la luciférase, le collagène de type I a été évalué dans les fibroblastes dermiques humains primaires par immunohistochimie, la modification du protéome du collagène des fibroblastes intracellulaires a été étudiée par spectrométrie de masse. La protéomique et le collagène de type III ont été évalués par immunohistochimie sur la peau humaine ex vivo. RÉSULTATS: la 10-HSA était l'agoniste PPARα le plus efficace (induction 15,7X ; p<0,001), suivi de la 9-HSA (induction 10,1X) puis de la 12-HSA (induction 4,9X) avec la 17-HSA (induction 1,7X) étant similaire aux effets de l'acide stéarique (induction 1,8X). Les niveaux de collagène de type I ont été augmentés dans les fibroblastes humains primaires de 2,12X et 1,56X pour la 10-HSA et la 9-HSA respectivement in vitro, la 10-HSA étant significative (p<0,05) : alors que la 12-HSA et la SA n'ont eu aucun effet statistique sur le témoin non traité. La 10-HSA et la 12-HSA ont légèrement modifié le protéome du collagène des fibroblastes intracellulaires avec des augmentations significatives des protéines de collagène alpha-1 (VI) et alpha-3 (VI), mais seule la 10-HSA a augmenté les niveaux de collagène alpha-2 (V), alpha -1 (III), alpha-1 (I) et alpha-2 (I) (tous p<0,05) avec des augmentations significativement différentes entre 10-HSA et 12-HSA pour le collagène alpha-1 (I), le collagène- 3 (VI) et Collagène alpha-2 (I) (p<0,01). Le collagène de type III dans la peau ex vivo a augmenté de +47 % (p<0,05) de 0,05 % (1,7 mM) de rétinol, de +70 % (p<0,01) de 0,01 % (0,33 mM) de 10-HSA et la combinaison a augmenté les niveaux de +240 % (p<0,01 pour chaque ingrédient). CONCLUSION: La chiral (R)-10-HSA s'est avérée supérieure à 9, 12 et 17-HSA en tant qu'agoniste de PPARα. De plus, la 10-HSA a stimulé la synthèse de collagène dans la culture de fibroblastes monocouche telle qu'évaluée par protéomique et immunohistochimique. De plus, nous montrons également les effets synergiques de la 10-HSA avec le rétinol sur la synthèse du collagène III dans les explants de peau. Ces résultats soulignent en outre l'efficacité de la 10-HSA en tant qu'agoniste de PPARα et ingrédient anti-âge cosmétiquement acceptable.

Supplemental 25-Hydroxycholecalciferol Is More Effective than Cholecalciferol in Raising Serum 25-Hydroxyvitamin D Concentrations in Older Adults.

BACKGROUND: There are few studies directly comparing the pharmacokinetics of 25-hydroxycholecalciferol [25(OH)D3] to cholecalciferol (D3). OBJECTIVES: The primary objectives were to compare the effectiveness of D3 and 25(OH)D3 in raising 25-hydroxyvitamin D [25(OH)D] serum concentrations and achieving steady state. METHODS: This was a randomized, double-blind, active comparator trial of 91 participants (53 females, 38 males), aged 63.3 ± 7.9 y. 25(OH)D3 (10, 15, and 20 µg) and D3 (20 µg) were dosed daily for 6 mo followed by 6 mo of washout. Frequent measurements of serum 25(OH)D were performed. Pharmacokinetic parameters were fitted for each individual and the treatment average was modeled with linear regression using the individual baseline level, sex, and gender as covariates. RESULTS: Mean baseline 25(OH)D was similar in all groups (47.1-49.5 nmol/L). Increases in 25(OH)D to steady state were higher in the 25(OH)D3 groups than in the D3 group [least squares (LS) means (95% CI): 50.1 (43.3-58.0), 72.5 (64.3-81.7), 97.4 (86.6-109.6) nmol/L in 10, 15, and 20 µg/d and 38.7 (33.1-45.2) nmol/L in the D3 group; P = 0.0173, P < 0.0001, P < 0.0001]. The rate to reach steady state was similar in all groups, but the time to reach 25(OH)D concentrations of 75 nmol/L was faster in the higher-dosed 25(OH)D3 groups than in the D3 group (7 and 10 d compared with 40 d, P < 0.0001 and P < 0.0001 for 15 and 20 µg/d). The rate of elimination was 59-109% higher in the 25(OH)D3 groups than in the D3 group. The area under the curve (AUC)/µg dose demonstrated that 25(OH)D3 was 3 times as effective as D3 at raising 25(OH)D concentrations. CONCLUSIONS: 25(OH)D3 is ∼3 times as effective as D3 at raising 25(OH)D concentrations. Once supplementation is discontinued, the elimination rate of 25(OH)D3 is faster than D3. This trial was registered at clinicaltrials.gov as NCT02333682.

Associations of vitamin D status with dietary intakes and physical activity levels among adults from seven European countries: the Food4Me study.

PURPOSE: To report the vitamin D status in adults from seven European countries and to identify behavioural correlates. METHODS: In total, 1075 eligible adult men and women from Ireland, Netherlands, Spain, Greece, UK, Poland and Germany, were included in the study. RESULTS: Vitamin D deficiency and insufficiency, defined as 25-hydroxy vitamin D3 (25-OHD3) concentration of <30 and 30-49.9 nmol/L, respectively, were observed in 3.3 and 30.6% of the participants. The highest prevalence of vitamin D deficiency was found in the UK and the lowest in the Netherlands (8.2 vs. 1.1%, P < 0.05). In addition, the prevalence of vitamin D insufficiency was higher in females compared with males (36.6 vs. 22.6%, P < 0.001), in winter compared with summer months (39.3 vs. 25.0%, P < 0.05) and in younger compared with older participants (36.0 vs. 24.4%, P < 0.05). Positive dose-response associations were also observed between 25-OHD3 concentrations and dietary vitamin D intake from foods and supplements, as well as with physical activity (PA) levels. Vitamin D intakes of ≥5 µg/day from foods and ≥5 µg/day from supplements, as well as engagement in ≥30 min/day of moderate- and vigorous-intensity PA were associated with higher odds (P < 0.05) for maintaining sufficient (≥50 nmol/L) 25-OHD3 concentrations. CONCLUSIONS: The prevalence of vitamin D deficiency varied considerably among European adults. Dietary intakes of ≥10 µg/day of vitamin D from foods and/or supplements and at least 30 min/day of moderate- and vigorous-intensity PA were the minimum thresholds associated with vitamin D sufficiency.

Effect of a combination of genistein, polyunsaturated fatty acids and vitamins D3 and K1 on bone mineral density in postmenopausal women: a randomized, placebo-controlled, double-blind pilot study.

PURPOSE: Many postmenopausal women desire non-pharmaceutical alternatives to hormone therapy for protection against osteoporosis. Soybean isoflavones, especially genistein, are being studied for this purpose. This study examined the effects of synthetic genistein in combination with other potential bone-protective dietary molecules on bone mineral density (BMD) in early postmenopausal women. METHODS: In this 6-month double-blind pilot study, 70 subjects were randomized to receive daily either calcium only or the geniVida™ bone blend (GBB), which consisted of genistein (30 mg/days), vitamin D3 (800 IU/days), vitamin K1 (150 µg/days) and polyunsaturated fatty acids (1 g polyunsaturated fatty acids as ethyl ester: eicosapentaenoic acid/docosahexaenoic acid ratio = ~2/1). Markers of bone resorption and formation and BMD at the femoral neck, lumbar spine, Ward's triangle, trochanter and intertrochanter, total hip and whole body were assessed. RESULTS: Subjects supplemented with the GBB (n = 30) maintained femoral neck BMD, whereas in the placebo group (n = 28), BMD significantly decreased (p = 0.007). There was also a significant difference (p < 0.05) in BMD between the groups at Ward's triangle in favor of the GBB group. Bone-specific alkaline phosphatase and N-telopeptide significantly increased in the GBB group in comparison with those in baseline and in the placebo group. The GBB was well tolerated, and there were no significant differences in adverse events between groups. CONCLUSIONS: The GBB may help to prevent osteoporosis and reduce fracture risk, at least at the hip, in postmenopausal women. Larger and longer-term clinical trials are warranted.

Infants' Folate Markers and Postnatal Growth in the First 4 Months of Life in Relation to Breastmilk and Maternal Plasma Folate.

BACKGROUND: Human milk is the sole source of folate in exclusively breastfed infants. We investigated whether human milk folate or maternal plasma folate are associated with infants' folate status and postnatal growth in the first 4 months of life. METHODS: Exclusively breastfed infants (n = 120) were recruited at age < 1 month (baseline). Blood samples were available at baseline and at the age of 4 months. Plasma and breastmilk samples were available from the mothers at 8 weeks postpartum. The concentrations of (6S)-5-methyltetrahydrofolate (5-MTHF) and different folate status markers were measured in samples of the infants and their mothers. The z-scores of weight, height, and head circumference of the infants were measured five times between baseline and 4 months. RESULTS: Women with 5-MTHF concentrations in breastmilk <39.9 nmol/L (median) had higher plasma 5-MTHF compared to those with milk 5-MTHF concentrations >39.9 nmol/L (mean (SD) plasma 5-MTHF = 23.3 (16.5) vs. 16.6 (11.9) nmol/L; p = 0.015). At the age of 4 months, infants of women who were higher suppliers of 5-MTHF in breastmilk had higher plasma folate than those of low-supplier women (39.2 (16.1) vs. 37.4 (22.4) nmol/L; adjusted p = 0.049). The concentrations of breastmilk 5-MTHF and maternal plasma folate were not associated with infants' longitudinal anthropometric measurements between baseline and 4 months. CONCLUSIONS: Higher 5-MTHF in breastmilk was associated with higher folate status in the infants and the depletion of folate in maternal circulation. No associations were seen between maternal or breastmilk folate and infants' anthropometrics. Adaptive mechanisms might counteract the effect of low milk folate on infant development.

Infant blood concentrations of folate markers and catabolites are modified by 5,10-methylenetetrahydrofolate reductase C677T genotype and dietary folate source.

BACKGROUND: Folate intake and polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene may affect folate metabolism in infants. OBJECTIVES: We investigated the association between infant's MTHFR C677T genotype, the dietary folate source, and concentrations of folate markers in the blood. METHODS: We studied 110 breastfed infants (reference) and 182 infants who were randomly assigned to receive infant formulas enriched with either 78 µg folic acid or 81 µg (6S)-5-methyltetrahydrofolate (5-MTHF) per 100 g milk powder for 12 wk. The blood samples were available at the ages of <1 mo (baseline) and 16 wk. MTHFR genotype and concentrations of folate markers and catabolites [i.e., para-aminobenzoylglutamate (pABG)] were analyzed. RESULTS: At baseline, carriers of the TT genotype (vs. CC) had lower mean (SD) concentrations (all in nmol/L) of red blood cell (RBC) folate [1194 (507) vs. 1440 (521), P = 0.033) and plasma pABG [5.7 (4.9) vs. 12.5 (8.1), P < 0.001] but higher plasma 5-MTHF [33.9 (16.8) vs. 24.0 (12.6), P < 0.001]. Irrespective of the genotype, infant formula with 5-MTHF (vs. folic acid) caused a significant increase in RBC folate concentration [1278 (466) vs. 947 (552), P < 0.001]. In breastfed infants, plasma concentrations of 5-MTHF and pABG increased significantly by 7.7 (20.5) and 6.4 (10.5), respectively, from baseline to 16 wk. Infant formula that complies with the present EU legislation for folate intake increased RBC folate and plasma pABG concentrations at 16 wk (P < 0.001) than formula-fed infants. At 16 wk, plasma pABG concentrations remained ∼50% lower in carriers of the TT (vs. the CC) genotype among all feeding groups. CONCLUSIONS: Folate intake from infant formula according to the present EU legislation increased RBC folate and plasma pABG concentrations in infants to a greater extent than breastfeeding, particularly in carriers of the TT genotype. However, this intake did not completely abolish the between-genotype differences in pABG. Whether these differences have any clinical relevance, however, remains unclear. This trial was registered at clinicaltrials.gov as NCT02437721.

Circulating and adipose tissue immune cells in tissue-specific insulin resistance in humans with overweight and obesity.

OBJECTIVE: A proinflammatory adipose tissue (AT) microenvironment and systemic low-grade inflammation may differentially affect tissue-specific insulin sensitivity. This study investigated the relationships of abdominal subcutaneous AT (aSAT) and circulating immune cells, aSAT gene expression, and circulating inflammatory markers with liver and skeletal muscle insulin sensitivity in people with overweight and obesity. METHODS: Individuals with overweight and obesity from the PERSonalized Glucose Optimization Through Nutritional Intervention (PERSON) Study (n = 219) and the Maastricht Study (replication cohort; n = 1256) underwent a seven-point oral glucose tolerance test to assess liver and muscle insulin sensitivity, and circulating inflammatory markers were determined. In subgroups, flow cytometry was performed to identify circulating and aSAT immune cells, and aSAT gene expression was evaluated. RESULTS: The relative abundances of circulating T cells, nonclassical monocytes, and CD56dim CD16+ natural killer cells were inversely associated with liver, but not muscle, insulin sensitivity in the PERSON Study. The inverse association between circulating (classical) monocytes and liver insulin sensitivity was confirmed in the Maastricht Study. In aSAT, immune cell populations were not related to insulin sensitivity. Furthermore, aSAT gene expression of interleukin 6 and CD14 was positively associated with muscle, but not liver, insulin sensitivity. CONCLUSIONS: The present findings demonstrate that circulating immune cell populations and inflammatory gene expression in aSAT show distinct associations with liver and muscle insulin sensitivity.

Resveratrol and ω-3 PUFAs Promote Human Macrophage Differentiation and Function.

Monocytes differentiate into M1 and M2 macrophages, which are classically activated by microbial products such as LPS or IFN-γ and interleukins (e.g., the anti-inflammatory and Th2 promoting IL-4), respectively. The contribution of nutrients or nutrient-based substances such as ω-3 polyunsaturated fatty acids (ω-3 PUFAs) and resveratrol (Res) on the differentiation and function of M1 and M2 macrophages was evaluated. THP-1 cells and peripheral blood mononuclear cells (PBMCs) were differentiated into M1 and M2 cells and activated with LPS/IFN-γ or IL-4/IL-13. Macrophage lineage specific surface determinants (e.g., CD11b, CD11c, CD14, CD206, CD209, CD274, HLA-DR, CCR7, CCR2) were analysed by cytofluorometry. Res and ω-3 PUFAs altered CD14, CD206, CD274 and HL-DR surface expression patterns in M1 and M2 macrophages differentiated from PBMC. LPS/IFN-γ or IL-14/IL-13 activated macrophages subpopulations, which secreted cytokines and chemokines as measured by multiplex ELISA. Res and ω-3 PUFA reduced IL-1ß, IL-6, TNF-α, CXCL10/IP-10, CCL13/MCP-4 and CCL20/MIP-3α in LPS/IFN-γ activated human leukaemia THP-1 cells, which is indicative of a dampening effect on M1 macrophages. However, Res increased M1 prototypic cytokines such as IL-1ß or IL-6 in macrophages derived from PBMCs and also modified the expression of IL-12p70. Collectively, Res and ω-3 PUFAs distinctly promoted the differentiation and function of M1 and M2 macrophages. We conclude that these substances strengthen the macrophage-mediated effects on the innate and adaptive immune response.

Transcriptome-Wide Profile of 25-Hydroxyvitamin D3 in Primary Immune Cells from Human Peripheral Blood.

Vitamin D3 is an essential micronutrient mediating pleiotropic effects in multiple tissues and cell types via its metabolite 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3), which activates the transcription factor vitamin D receptor. In this study, we used peripheral blood mononuclear cells (PBMCs) obtained from five healthy adults and investigated transcriptome-wide, whether the precursor of 1,25(OH)2D3, 25-hydroxyvitamin D3 (25(OH)D3), has gene regulatory potential on its own. Applying thresholds of >2 in fold change of gene expression and <0.05 as a false discovery rate, in this ex vivo approach the maximal physiological concentration of 25(OH)D3 (250 nM (nmol/L)) none of the study participants had a significant effect on their PBMC transcriptome. In contrast, 1000 and 10,000 nM 25(OH)D3 regulated 398 and 477 genes, respectively, which is comparable to the 625 genes responding to 10 nM 1,25(OH)2D3. The majority of these genes displayed specificity to the tested individuals, but not to the vitamin D metabolite. Interestingly, the genes MYLIP (myosin regulatory light chain interacting protein) and ABCG1 (ATP binding cassette subfamily G member 1) showed to be specific targets of 10,000 nM 25(OH)D3. In conclusion, 100- and 1000-fold higher 25(OH)D3 concentrations than the reference 10 nM 1,25(OH)2D3 are able to affect the transcriptome of PBMCs with a profile comparable to that of 1,25(OH)2D3.

Common and personal target genes of the micronutrient vitamin D in primary immune cells from human peripheral blood.

Vitamin D is essential for the function of the immune system. In this study, we treated peripheral blood mononuclear cells (PBMCs) of healthy adults with the biologically active form of vitamin D3, 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) using two different approaches: single repeats with PBMCs obtained from a cohort of 12 individuals and personalized analysis based on triplicates of five study participants. This identified 877 (cohort approach) and 3951 (personalized approach) genes that significantly (p < 0.05) changed their expression 24 h after 1,25(OH)2D3 stimulation. From these, 333 and 1232 were classified as supertargets, a third of which were identified as novel. Individuals differed largely in their vitamin D response not only by the magnitude of expression change but also by their personal selection of (super)target genes. Functional analysis of the target genes suggested the overarching role of vitamin D in the regulation of metabolism, proliferation and differentiation, but in particular in the control of functions mediated by the innate and adaptive immune system, such as responses to infectious diseases and chronic inflammatory disorders. In conclusion, immune cells are an important target of vitamin D and common genes may serve as biomarkers for personal responses to the micronutrient.

The effects of polyphenol supplementation on adipose tissue morphology and gene expression in overweight and obese humans.

Dietary polyphenols have beneficial effects on adipose tissue mass and function in rodents, but human studies are scarce. In a randomized, placebo-controlled study, 25 (10 women) overweight and obese humans received a combination of the polyphenols epigallocatechin-gallate and resveratrol (282 mg/d, 80 mg/d, respectively, EGCG+RES, n = 11) or placebo (PLA, n = 14) supplementation for 12 weeks. Abdominal subcutaneous adipose tissue (SAT) biopsies were collected for assessment of adipocyte morphology and micro-array analysis. EGCG+RES had no effects on adipocyte size and distribution compared with PLA. However, we identified pathways contributing to adipogenesis, cell cycle and apoptosis were significantly downregulated by EGCG+RES versus PLA. Furthermore, EGCG+RES significantly decreased expression of pathways related to energy metabolism, oxidative stress, inflammation, and immune defense as compared with PLA. In conclusion, the SAT gene expression profile indicates a reduced cell turnover after 12-week EGCG+RES in overweight-obese subjects. It remains to be elucidated whether these alterations translate into long-term metabolic effects.

Large-Scale Screening of Natural Products Transactivating Peroxisome Proliferator-Activated Receptor α Identifies 9S-Hydroxy-10E,12Z,15Z-Octadecatrienoic Acid and Cymarin as Potential Compounds Capable of Increasing Apolipoprotein A-I Transcription in Human Liver Cells.

Increasing apolipoprotein A-I (apoA-I), the predominant protein of high-density lipoprotein (HDL) particles, has favorable effects on atherogenic risk factors. Here, we investigated the effects of peroxisome proliferator-activated receptor α (PPARα) transactivating compounds on apoA-I transcription in HepG2 cells. A transient PPARα agonist transactivation assay was used to screen 2500 natural compounds. To analyze the effects on apoA-I transcription, human hepatocellular liver carcinoma (HepG2) were exposed to 0.1, 1, and 10 µg/mL of the natural PPARα transactivators. ApoA-I mRNA expression was determined by quantitative polymerase chain reaction. Extensive dose-response experiments were performed using compounds that increased apoA-I transcription by minimally 20%. Kelch-like ECH-associated protein 1 (KEAP) and carnitine palmitoyltransferase 1 alpha (CPT1α) expression were used respectively to confirm Bromodomain-containing protein 4 inhibition or PPARα activation. Twenty-eight natural compounds increased PPARα transactivation by at least twofold. Despite the increased CPT1α expression seen after the addition of most PPARα activating compounds, CPT1α expression and PPARα transactivation did not correlate. Addition of 0.05 µg/mL 9S-hydroxy-10E,12Z,15Z-octadecatrienoic acid (9(S)-HOTrE) increased apoA-I mRNA expression by 35%, whereas 10-25 µg/mL of cymarin increased apoA-I transcription by 37%. However, combining cymarin and 9(S)-HOTrE did not result in a synergistic effect, in contrast this combination even decreased apoA-I transcription. ApoA-I transcription involves multiple regulatory players, and PPARα transactivation alone is not sufficient. A search for natural compounds resembling the molecular structure of 9(S)-HOTrE or cymarin could aid to find additional components that increase apoA-I transcription.

Weekday sunlight exposure, but not vitamin D intake, influences the association between vitamin D receptor genotype and circulating concentration 25-hydroxyvitamin D in a pan-European population: the Food4Me study.

SCOPE: Little is known about diet- and environment-gene interactions on 25-hydroxyvitamin D (25(OH)D concentration. This cross-sectional study aimed to investigate (i) predictors of 25(OH)D concentration and relationships with vitamin D genotypes and (ii) whether dietary vitamin D intake and sunlight exposure modified these relationships. METHODS AND RESULTS: Participants from the Food4Me study (n = 1312; age 18-79) were genotyped for vitamin D receptor (VDR) and vitamin D binding protein at baseline and a genetic risk score was calculated. Dried blood spot samples were assayed for 25(OH)D concentration and dietary and lifestyle information collected. Circulating 25(OH)D concentration was lower with increasing genetic risk score, lower in females than males, higher in supplement users than non-users and higher in summer than winter. Carriage of the minor VDR allele was associated with lower 25(OH)D concentration in participants with the least sunlight exposure. Vitamin D genotype did not influence the relationship between vitamin D intake and 25(OH)D concentration. CONCLUSION: Age, sex, dietary vitamin D intake, country, sunlight exposure, season, and vitamin D genetic risk score were associated with circulating 25(OH)D concentration in a pan-European population. The relationship between VDR genotype and 25(OH)D concentration may be influenced by weekday sunlight exposure but not dietary vitamin D intake.

Proposed guidelines to evaluate scientific validity and evidence for genotype-based dietary advice.

Nutrigenetic research examines the effects of inter-individual differences in genotype on responses to nutrients and other food components, in the context of health and of nutrient requirements. A practical application of nutrigenetics is the use of personal genetic information to guide recommendations for dietary choices that are more efficacious at the individual or genetic subgroup level relative to generic dietary advice. Nutrigenetics is unregulated, with no defined standards, beyond some commercially adopted codes of practice. Only a few official nutrition-related professional bodies have embraced the subject, and, consequently, there is a lack of educational resources or guidance for implementation of the outcomes of nutrigenetic research. To avoid misuse and to protect the public, personalised nutrigenetic advice and information should be based on clear evidence of validity grounded in a careful and defensible interpretation of outcomes from nutrigenetic research studies. Evidence requirements are clearly stated and assessed within the context of state-of-the-art 'evidence-based nutrition'. We have developed and present here a draft framework that can be used to assess the strength of the evidence for scientific validity of nutrigenetic knowledge and whether 'actionable'. In addition, we propose that this framework be used as the basis for developing transparent and scientifically sound advice to the public based on nutrigenetic tests. We feel that although this area is still in its infancy, minimal guidelines are required. Though these guidelines are based on semi-quantitative data, they should stimulate debate on their utility. This framework will be revised biennially, as knowledge on the subject increases.

Combined epigallocatechin-3-gallate and resveratrol supplementation for 12 wk increases mitochondrial capacity and fat oxidation, but not insulin sensitivity, in obese humans: a randomized controlled trial.

BACKGROUND: The obese insulin-resistant state is characterized by impairments in lipid metabolism. We previously showed that 3-d supplementation of combined epigallocatechin-3-gallate and resveratrol (EGCG+RES) increased energy expenditure and improved the capacity to switch from fat toward carbohydrate oxidation with a high-fat mixed meal (HFMM) test in men. OBJECTIVE: The present study aimed to investigate the longer-term effect of EGCG+RES supplementation on metabolic profile, mitochondrial capacity, fat oxidation, lipolysis, and tissue-specific insulin sensitivity. DESIGN: In this randomized double-blind study, 38 overweight and obese subjects [18 men; aged 38 ± 2 y; body mass index (kg/m(2)): 29.7 ± 0.5] received either EGCG+RES (282 and 80 mg/d, respectively) or placebo for 12 wk. Before and after the intervention, oxidative capacity and gene expression were assessed in skeletal muscle. Fasting and postprandial (HFMM) lipid metabolism was assessed by using indirect calorimetry, blood sampling, and microdialysis. Tissue-specific insulin sensitivity was assessed by a hyperinsulinemic-euglycemic clamp with [6,6-(2)H2]-glucose infusion. RESULTS: EGCG+RES supplementation did not affect the fasting plasma metabolic profile. Although whole-body fat mass was not affected, visceral adipose tissue mass tended to decrease after the intervention compared with placebo (P-time × treatment = 0.09). EGCG+RES supplementation significantly increased oxidative capacity in permeabilized muscle fibers (P-time × treatment < 0.05, P-EGCG+RES < 0.05). Moreover, EGCG+RES reduced fasting (P-time × treatment = 0.03) and postprandial respiratory quotient (P-time × treatment = 0.01) compared with placebo. Fasting and postprandial fat oxidation was not significantly affected by EGCG+RES (P-EGCG+RES = 0.46 and 0.38, respectively) but declined after placebo (P-placebo = 0.05 and 0.03, respectively). Energy expenditure was not altered (P-time × treatment = 0.96). Furthermore, EGCG+RES supplementation attenuated the increase in plasma triacylglycerol concentrations during the HFMM test that was observed after placebo (P-time × treatment = 0.04, P-placebo = 0.01). Finally, EGCG+RES had no effect on insulin-stimulated glucose disposal, suppression of endogenous glucose production, or lipolysis. CONCLUSION: Twelve weeks of EGCG+RES supplementation increased mitochondrial capacity and stimulated fat oxidation compared with placebo, but this did not translate into increased tissue-specific insulin sensitivity in overweight and obese subjects. This trial was registered at clinicaltrials.gov as NCT02381145.

Phytanic acid, a natural peroxisome proliferator-activated receptor (PPAR) agonist, regulates glucose metabolism in rat primary hepatocytes.

Phytanic acid, a metabolite of the chlorophyll molecule, is part of the human diet and is present in normal human serum at low micromolar concentrations. It was previously shown to be a ligand of the 9-cis-retinoic acid receptor and peroxisome proliferator-activated receptor (PPAR) a. PPAR agonists are widely used in the treatment of type 2 diabetes. Here, we report that phytanic acid is not only a transactivator of PPARa, but it also acts via PPARb and PPARg in CV-1 cells that have been cotransfected with the respective full-length receptor and an acyl-CoA oxidase-PPAR-responsive element-luciferase construct. We observed that, in contrast to other fatty acids, phytanic acid at physiological concentrations enhances uptake of 2-deoxy-D-glucose in rat primary hepatocytes. This result could be explained by the increase in mRNA expression of glucose transporters-1 and -2 and glucokinase, as determined by quantitative real-time reverse transcriptase-polymerase chain reaction. Compared with the PPARg-specific agonist ciglitazone, phytanic acid exerts only minor effects on the differentiation of C3H10T1/2 cells into mature adipocytes. These results clearly demonstrate that phytanic acid acts via different PPAR isoforms to modulate expression of genes involved in glucose metabolism, thus suggesting a potential role of phytanic acid in the management of insulin resistance.

Target Fishing by Cross-Docking to Explain Polypharmacological Effects.

Drugs may have polypharmacological phenomena, that is, in addition to the desired target, they may also bind to many undesired or unknown physiological targets. As a result, they often exert side effects. In some cases, off-target interactions may lead to drug repositioning or to explaining a drug's mode of action. Herein we present an in silico approach for target fishing by cross-docking as a method to identify new drug-protein interactions. As an example and proof of concept, this method predicted the peroxisome proliferator-activated receptor (PPAR)-γ as a target of ethacrynic acid, which may explain the hyperglycemic effect brought on by this molecule. The antagonistic effect of ethacrynic acid on PPAR-γ was validated in a transient transactivation assay using human HEK293 cells. The cross-docking approach also predicted the potential mechanisms of many other drug side effects and discloses new drug repositioning opportunities. These putative interactions are described herein, and can be readily used to discover therapeutically relevant drug effects.

A 3-day EGCG-supplementation reduces interstitial lactate concentration in skeletal muscle of overweight subjects.

Green tea, particularly epigallocatechin-3-gallate (EGCG), may affect body weight and composition, possibly by enhancing fat oxidation. The aim of this double-blind, randomized placebo-controlled cross-over study was to investigate whether 3-day supplementation with EGCG (282 mg/day) stimulates fat oxidation and lipolysis in 24 overweight subjects (age = 30 ± 2 yrs, BMI = 27.7 ± 0.3 kg/m(2)). Energy expenditure, substrate metabolism and circulating metabolites were determined during fasting and postprandial conditions. After 6 h, a fat biopsy was collected to examine gene expression. In 12 subjects, skeletal muscle glycerol, glucose and lactate concentrations were determined using microdialysis. EGCG-supplementation did not alter energy expenditure and substrate oxidation compared to placebo. Although EGCG reduced postprandial circulating glycerol concentrations (P = 0.015), no difference in skeletal muscle lipolysis was observed. Fasting (P = 0.001) and postprandial (P = 0.003) skeletal muscle lactate concentrations were reduced after EGCG-supplementation compared to placebo, despite similar tissue blood flow. Adipose tissue leptin (P = 0.05) and FAT/CD36 expression (P = 0.08) were increased after EGCG compared to placebo. In conclusion, 3-day EGCG-supplementation decreased postprandial plasma glycerol concentrations, but had no significant effects on skeletal muscle lipolysis and whole-body fat oxidation in overweight individuals. Furthermore, EGCG decreased skeletal muscle lactate concentrations, which suggest a shift towards a more oxidative muscle phenotype.

Expression of COX-2 and Wnt pathway genes in adenomas of familial adenomatous polyposis patients treated with meloxicam.

BACKGROUND: Familial adenomatous polyposis (FAP) is an autosomal, dominantly inherited predisposition to colorectal cancer caused by germline mutations within the adenomatous polyposis coli (APC) gene, a key member of the Wnt signalling pathway. A new class of non-steroidal anti-inflammatory drugs (NSAIDs), the specific cyclooxygenase 2 (COX-2) inhibitors, have recently been applied for the treatment of FAP patients. PATIENTS AND METHODS: The expressions of the Wnt members and targets APC, c-myc, cyclin D1 and COX-2, as measured by real-time quantitative RT-PCR, have been evaluated in fresh samples of normal colorectal mucosa and matched adenoma tissue of six unrelated FAP patients before and after treatment with meloxicam. RESULTS: A significant up-regulation of COX-2 in adenomas after treatment with meloxicam was found. Furthermore, in adenomas, a down-regulation of APC after treatment and a tight correlation of the expressions of the two Wnt targets, c-myc and cyclin D1, in both stages of treatment were observed. CONCLUSION: A feedback loop mediated by the peroxisome proliferator-activated receptor (PPAR) gamma is discussed as being responsible for the up-regulation of COX-2