Genome-wide association study of osteoporosis identifies genetic risk and interactions with DASH diet and sugar sweetened beverages in a Hispanic cohort of older adults.

BACKGROUND: Osteoporosis (OP) and low bone mass can be debilitating and costly conditions if not acted on quickly. This disease is also difficult to diagnose as symptoms develop unnoticed until fracture occurs. Therefore, gaining understanding of the genetic risk associated with these conditions could be beneficial for healthcare professionals in early detection and prevention. METHODS: The Boston Puerto Rican Osteoporosis (BPROS) study, an ancillary study to the Boston Puerto Rican Health Study (BPRHS), collected information regarding bone and bone health. All bone measurements were taken during regular BPROS visits using dual-energy x-ray absorptiometry. Osteoporosis was defined as T-score ≤ -2.5 (2.5 SD or more below peak bone mass). Dietary variables were collected at the second wave of the BPRHS via food frequency questionnaire. We conducted genome-wide associations with bone outcomes including bone mineral density (BMD) and OP for 978 participants. We also examined interactions with dietary quality on the relationships between genotype and bone outcomes. We further tested if candidate genetic variants described in previous GWAS on OP and BMD contribute to OP risk in this population. RESULTS: Four variants were associated with OP: rs114829316 (IQCJ), rs76603051, rs12214684 (MCHR2), and rs77303493 (RIN2), and two variants with BMD of lumbar spine (rs11855618, CGNL1) and hip (rs73480593, NTRK2), reaching the genome-wide significance threshold of P ≤ 5E-08. In a gene-diet interaction analysis, we found that one SNP showed a significant interaction with the overall DASH score, and 7 SNPs with sugar-sweeten beverages, a major contributor to the DASH score. CONCLUSION: This study identifies new genetic markers related to osteoporosis and BMD in older Hispanic adults. Additionally, we uncovered unique genetic markers that interact with dietary quality, specifically sugar-sweetened beverages, in relation to bone health. These findings may be useful to guide early detection and preventative care.

Sex-specific differences in intestinal microbiota associated with cardiovascular diseases.

BACKGROUND: Cardiovascular diseases (CVD), including coronary heart disease (CHD), display a higher prevalence in men than women. This study aims to evaluate the variations in the intestinal microbiota between men and women afflicted with CHD and delineate these against a non-CVD control group for each sex. METHODS: Our research was conducted in the framework of the CORDIOPREV study, a clinical trial which involved 837 men and 165 women with CHD. We contrasted our findings with a reference group of 375 individuals (270 men, 105 women) without CVD. The intestinal microbiota was examined through 16S metagenomics on the Illumina MiSeq platform and the data processed with Quiime2 software. RESULTS: Our results showed a sex-specific variation (beta diversity) in the intestinal microbiota, while alpha-biodiversity remained consistent across both sexes. Linear discriminant analysis effect size (LEfSe) analysis revealed sex-centric alterations in the intestinal microbiota linked to CVD. Moreover, using random forest (RF) methodology, we identified seven bacterial taxa-g_UBA1819 (Ruminococcaceae), g_Bilophila, g_Subdoligranulum, g_Phascolarctobacterium, f_Barnesiellaceae, g_Ruminococcus, and an unknown genus from the Ruminococcaceae family (Ruminococcaceae incertae sedis)-as key discriminators between men and women diagnosed with CHD. The same taxa also emerged as critical discriminators between CHD-afflicted and non-CVD individuals, when analyzed separately by sex. CONCLUSION: Our findings suggest a sex-specific dysbiosis in the intestinal microbiota linked to CHD, potentially contributing to the sex disparity observed in CVD incidence. Trial registration Clinical Trials.gov.Identifier NCT00924937.

The frequency with which cardiovascular diseases occur differs in men and women as it appears with greater frequency in men. Moreover, it has been known for years that the community of bacteria living in our intestine, also known as the gut microbiota, influences the development of these diseases. Indeed, nowadays it known the influence of the intestinal microbiota in the development of atherosclerosis, the pathological process which is responsible for the three main causes of cardiovascular diseases: coronary heart disease, cerebrovascular disease and peripheral arterial disease. This study shows the differences in the community of bacteria living in the gut of men and those living in the gut of women, so that these differences could explain, at least in part, the differences in the frequency with which cardiovascular diseases appear between men and women. Our results suggest that the dysbiosis of the intestinal microbiota associated with CHD seems to be partially sex-specific, which may influence the sexual dimorphism in its incidence. Moreover, the identification of the mechanisms responsible for sexual dimorphism in the incidence of metabolic and cardiovascular disease is of particular importance when developing effective strategies and therapies aimed at reducing their incidence and recurrence. Indeed, the strategies and therapies used to treat the dysbiosis of the gut microbiota should be sex-specific.

Telomere Maintenance Is Associated with Type 2 Diabetes Remission in Response to a Long-Term Dietary Intervention without Non-Weight Loss in Patients with Coronary Heart Disease: From the CORDIOPREV Randomized Controlled Trial.

In order to evaluate whether telomere maintenance is associated with type 2 diabetes remission, newly diagnosed type 2 diabetes patients without glucose-lowering treatment (183 out of 1002) from the CORDIOPREV study (NCT00924937) were randomized to consume a Mediterranean or low-fat diet. Patients were classified as Responders, those who reverted from type 2 diabetes during the 5 years of dietary intervention (n = 69), and Non-Responders, who did not achieve diabetes remission by the end of the follow-up period (n = 104). We found no differences in diabetes remission between the two diets, and we determined telomere length (TL) by measuring qPCR, telomerase activity using the TRAP assay, and direct redox balance based on the ratio of reduced glutathione (GSH) to oxidized glutathione (GSSH) via colorimetric assay. Responders exhibited higher baseline TL in comparison with Non-Responders (p = 0.040), and a higher TL at baseline significantly predicted a higher probability of type 2 diabetes remission (OR 2.13; 95% CI, 1.03 to 4.41). After the dietary intervention, Non-Responders showed significant telomere shortening (-0.19, 95% CI -0.32 to 0.57; p = 0.005). Telomere shortening was significantly pronounced in type 2 diabetes patients with a worse profile of insulin resistance and/or beta-cell functionality: high hepatic insulin resistance fasting, a high disposition index (-0.35; 95% CI, -0.54 to -0.16; p < 0.001), and a low disposition index (-0.25; 95% CI, -0.47 to -0.01; p = 0.037). In addition, changes in TL were correlated to the GSH/GSSG ratio. Responders also showed increased telomerase activity compared with baseline (p = 0.048), from 0.16 (95% CI, 0.08 to 0.23) to 0.28 (95% CI, 0.15 to 0.40), with a more marked increase after the dietary intervention compared with Non-Responders (+0.07; 95% CI, -0.06-0.20; p = 0.049). To conclude, telomere maintenance may play a key role in the molecular mechanisms underlying type 2 diabetes remission in newly diagnosed patients. However, further larger-scale prospective studies are necessary to corroborate our findings.

Dietary antioxidant intake reduces carotid intima-media thickness in coronary heart disease patients: From the CORDIOPREV study.

BACKGROUND: Atherosclerosis is the leading underlying cause of coronary heart disease (CHD). In patients with CHD, intima-media thickness of common carotid arteries (IMT-CC) is a reliable, validated, and non-invasive marker of the progression of atherosclerosis. Dietary intervention may affect IMT-CC evolution through different pathways. There is a lack of clinical trials evaluating the effect of total dietary antioxidant content of diets on IMT-CC, especially in patients with CHD. OBJECTIVE: We evaluated the correlation between the diet's total antioxidant content and the changes in IMT-CC produced after 5 years of dietary intervention following two healthy diet models (Mediterranean diet and low-fat diet). We also evaluated whether the diet's total antioxidant content was related to the total redox capacity of the participants. METHODS: From the total participants of the CORDIOPREV study (clinical trial register NCT00924937), 805 participants completed the IMT-CC measurement and the dietary antioxidant evaluation at baseline and after 5 years of dietary intervention. IMT-CC was carried out by ultrasound and the dietary antioxidant evaluation was performed by the Dietary Antioxidant Index (DAI). Additionally, direct redox balance was evaluated in a subset of population by the ratio of reduced glutathione (GSH) to oxidized glutathione (GSSH) by colorimetric assay. RESULTS: We observed an inverse correlation between evolution of DAI and IMT-CC after 5-years of dietary intervention. The mean of the DAI index augmented in the Mediterranean Diet group, whereas it decreased in the Low-fat group. DAI was correlated to the GSH/GSSG ratio, supporting DAI as an adequate estimator of diet's antioxidant content. When looking for individual components of the DAI that were associated to the changes in IMT-CC, an inverse correlation was found for carotenoids, vitamin E, vitamin C, and zinc and the IMT-CC. CONCLUSIONS: Our study indicates that, after five years of dietary intervention, changes in DAI inversely correlate with changes in IMT-CC in patients with CHD. Overall effect of Mediterranean diet resulted in an increase of DAI, conversely to low-fat. Specific elements included in the DAI index were inversely correlated with IMT-CC.

Corrigendum: APOE4 allele-specific associations between diet, multimodal biomarkers, and cognition among Puerto Rican adults in Massachusetts.

[This corrects the article DOI: 10.3389/fnagi.2023.1285333.].

Associations between the New DNA-Methylation-Based Telomere Length Estimator, the Mediterranean Diet and Genetics in a Spanish Population at High Cardiovascular Risk.

Biological aging is a relevant risk factor for chronic diseases, and several indicators for measuring this factor have been proposed, with telomere length (TL) among the most studied. Oxidative stress may regulate telomere shortening, which is implicated in the increased risk. Using a novel estimator for TL, we examined whether adherence to the Mediterranean diet (MedDiet), a highly antioxidant-rich dietary pattern, is associated with longer TL. We determined TL using DNA methylation algorithms (DNAmTL) in 414 subjects at high cardiovascular risk from Spain. Adherence to the MedDiet was assessed by a validated score, and genetic variants in candidate genes and at the genome-wide level were analyzed. We observed several significant associations (p < 0.05) between DNAmTL and candidate genes (TERT, TERF2, RTEL1, and DCAF4), contributing to the validity of DNAmTL as a biomarker in this population. Higher adherence to the MedDiet was associated with lower odds of having a shorter TL in the whole sample (OR = 0.93; 95% CI: 0.85-0.99; p = 0.049 after fully multivariate adjustment). Nevertheless, this association was stronger in women than in men. Likewise, in women, we observed a direct association between adherence to the MedDiet score and DNAmTL as a continuous variable (beta = 0.015; SE: 0.005; p = 0.003), indicating that a one-point increase in adherence was related to an average increase of 0.015 ± 0.005 kb in TL. Upon examination of specific dietary items within the global score, we found that fruits, fish, "sofrito", and whole grains exhibited the strongest associations in women. The novel score combining these items was significantly associated in the whole population. In the genome-wide association study (GWAS), we identified ten polymorphisms at the suggestive level of significance (p < 1 × 10-5) for DNAmTL (intergenics, in the IQSEC1, NCAPG2, and ABI3BP genes) and detected some gene-MedDiet modulations on DNAmTL. As this is the first study analyzing the DNAmTL estimator, genetics, and modulation by the MedDiet, more studies are needed to confirm these findings.

Therapeutic potential of plant-derived extracellular vesicles as nanocarriers for exogenous miRNAs.

Cell-to-cell communication strategies include extracellular vesicles (EVs) in plants and animals. The bioactive molecules in a diet rich in vegetables and fruits are associated with disease-preventive effects. Plant-derived EVs (PDEVs) are biogenetically and morphologically comparable to mammalian EVs and transport bioactive molecules, including miRNAs. However, the biological functions of PDEVs are not fully understood, and standard isolation protocols are lacking. Here, PDEVs were isolated from four foods with a combination of ultracentrifugation and size exclusion chromatography, and evaluated as vehicles for enhanced transport of synthetic miRNAs. In addition, the role of food-derived EVs as carriers of dietary (poly)phenols and other secondary metabolites was investigated. EVs from broccoli, pomegranate, apple, and orange were efficiently isolated and characterized. In all four sources, 4 miRNA families were present in tissues and EVs. miRNAs present in broccoli and fruit-derived EVs showed a reduced RNase degradation and were ferried inside exposed cells. EVs transfected with a combination of ath-miR159a, ath-miR162a-3p, ath-miR166b-3p, and ath-miR396b-5p showed toxic effects on human cells, as did natural broccoli EVs alone. PDEVs transport trace amounts of phytochemicals, including flavonoids, anthocyanidins, phenolic acids, or glucosinolates. Thus, PDEVs can act as nanocarriers for functional miRNAs that could be used in RNA-based therapy.

APOE4 allele-specific associations between diet, multimodal biomarkers, and cognition among Puerto Rican adults in Massachusetts.

Background: Apolipoprotein E (APOE) is the strongest genetic risk factor for sporadic Alzheimer's Disease (AD), and the ε4 allele (APOE4) may interact with lifestyle factors that relate to brain structural changes, underlying the increased risk of AD. However, the exact role of APOE4 in mediating interactions between the peripheral circulatory system and the central nervous system, and how it may link to brain and cognitive aging requires further elucidation. In this analysis, we investigated the association between APOE4 carrier status and multimodal biomarkers (diet, blood markers, clinical diagnosis, brain structure, and cognition) in the context of gene-environment interactions. Methods: Participants were older adults from a longitudinal observational study, the Boston Puerto Rican Health Study (BPRHS), who self-identified as of Puerto Rican descent. Demographics, APOE genotype, diet, blood, and clinical data were collected at baseline and at approximately 12th year, with the addition of multimodal brain magnetic resonance imaging (MRI) (T1-weighted and diffusion) and cognitive testing acquired at 12-year. Measures were compared between APOE4 carriers and non-carriers, and associations between multimodal variables were examined using correlation and multivariate network analyses within each group. Results: A total of 156 BPRHS participants (mean age at imaging = 68 years, 77% female, mean follow-up 12.7 years) with complete multimodal data were included in the current analysis. APOE4 carriers (n = 43) showed reduced medial temporal lobe (MTL) white matter (WM) microstructural integrity and lower mini-mental state examination (MMSE) score than non-carriers (n = 113). This pattern was consistent with an independent sample from the Alzheimer's Disease Neuroimaging Initiative (ADNI) of n = 283 non-Hispanic White adults without dementia (mean age = 75, 40% female). Within BPRHS, carriers showed distinct connectivity patterns between multimodal biomarkers, characterized by stronger direct network connections between baseline diet/blood markers with 12-year blood/clinical measures, and between blood markers (especially lipids and cytokines) and WM. Cardiovascular burden (i.e., hypertension and diabetes status) was associated with WM integrity for both carriers and non-carriers. Conclusion: APOE4 carrier status affects interactions between dietary factors, multimodal blood biomarkers, and MTL WM integrity across ~12 years of follow-up, which may reflect increased peripheral-central systems crosstalk following blood-brain barrier breakdown in carriers.

The Personalized Nutrition Study (POINTS): evaluation of a genetically informed weight loss approach, a Randomized Clinical Trial.

Weight loss (WL) differences between isocaloric high-carbohydrate and high-fat diets are generally small; however, individual WL varies within diet groups. Genotype patterns may modify diet effects, with carbohydrate-responsive genotypes losing more weight on high-carbohydrate diets (and vice versa for fat-responsive genotypes). We investigated whether 12-week WL (kg, primary outcome) differs between genotype-concordant and genotype-discordant diets. In this 12-week single-center WL trial, 145 participants with overweight/obesity were identified a priori as fat-responders or carbohydrate-responders based on their combined genotypes at ten genetic variants and randomized to a high-fat (n = 73) or high-carbohydrate diet (n = 72), yielding 4 groups: (1) fat-responders receiving high-fat diet, (2) fat-responders receiving high-carbohydrate diet, (3) carbohydrate-responders receiving high-fat diet, (4) carbohydrate-responders receiving high-carbohydrate diet. Dietitians delivered the WL intervention via 12 weekly diet-specific small group sessions. Outcome assessors were blind to diet assignment and genotype patterns. We included 122 participants (54.4 [SD:13.2] years, BMI 34.9 [SD:5.1] kg/m2, 84% women) in the analyses. Twelve-week WL did not differ between the genotype-concordant (-5.3 kg [SD:1.0]) and genotype-discordant diets (-4.8 kg [SD:1.1]; adjusted difference: -0.6 kg [95% CI: -2.1,0.9], p = 0.50). With the current ability to genotype participants as fat- or carbohydrate-responders, evidence does not support greater WL on genotype-concordant diets. ClinicalTrials identifier: NCT04145466.

Association between telomere length and intima-media thickness of both common carotid arteries in patients with coronary heart disease: From the CORDIOPREV randomized controlled trial.

BACKGROUND AND AIMS: A critical telomere length (TL) is associated with cardiovascular mortality. Dietary habits have been demonstrated to affect cardiovascular risk. However, it remains unclear how exactly TL determines the response to specific dietary approaches in the reduction of arterial injury. We aimed to evaluate whether TL was associated with the progression of arterial injury (assessed by intima-media thickness of both common carotid arteries: IMT-CC), after long-term consumption of two healthy dietary models in patients with coronary heart disease (CHD). METHODS: From the 1002 CHD patients of the CORDIOPREV study, 903 completed IMT-CC and TL evaluation at baseline and were randomized to follow a Mediterranean diet or a low-fat diet for 5 years. RESULTS: Patients at risk of short TL (TL < 20th percentile) presented an elevated IMT-CC, (0.79 ± 0.17 vs patients at non-risk 0.74 ± 0.17 p < 0.001). TL and IMT-CC showed an inverse association (ß = -0.035, p = 0.002). Patients who consumed a Mediterranean diet, regardless of the risk of short TL, showed a significant decrease in IMT-CC, with a higher reduction in those patients with risk of short TL (-0.03 ± 0.11, p = 0.036). TL (ß = 0.019, p = 0.024), age (ß = -0.001, p = 0.031), energy intake (ß = -0.000, p = 0.036), use of statins (ß = -0.027, p = 0.028) and allocation into the Mediterranean diet (vs low-fat diet) (ß = -0.024, p = 0.003) were significant contributors to changes in IMT-CC. CONCLUSIONS: Patients who had a reduced TL exhibited a greater decrease in IMT-CC after consuming a Mediterranean diet.

Rate-Limiting Enzymes in Cardiometabolic Health and Aging in Humans.

INTRODUCTION: Rate-limiting enzymes (RLEs) are innate slow points in metabolic pathways, and many function in bio-processes related to nutrient sensing. Many RLEs carry causal mutations relevant to inherited metabolic disorders. Because the activity of RLEs in cardiovascular health is poorly characterized, our objective was to assess their involvement in cardiometabolic health and disease and where altered biophysical and biochemical functions can promote disease. METHODS: A dataset of 380 human RLEs was compared to protein and gene datasets for factors likely to contribute to cardiometabolic disease, including proteins showing significant age-related altered expression in blood and genetic loci with variants that associate with common cardiometabolic phenotypes. The biochemical reactions catalyzed by RLEs were evaluated for metabolites enriched in RLE subsets associating with various cardiometabolic phenotypes. Most significance tests were based on Z-score enrichment converted to p values with a normal distribution function. RESULTS: Of 380 RLEs analyzed, 112 function in mitochondria, and 53 are assigned to inherited metabolic disorders. There was a depletion of RLE proteins known as aging biomarkers. At the gene level, RLEs were assessed for common genetic variants that associated with important cardiometabolic traits of LDL-cholesterol or any of the five outcomes pertinent to metabolic syndrome. This revealed several RLEs with links to cardiometabolic traits, from a minimum of 26 for HDL-cholesterol to a maximum of 45 for plasma glucose. Analysis of these GWAS-linked RLEs for enrichment of the molecular constituents of the catalyzed reactions disclosed a number of significant phenotype-metabolite links. These included blood pressure with acetate (p = 2.2 × 10-4) and NADP+ (p = 0.0091), plasma HDL-cholesterol and triglyceride with diacylglycerol (p = 2.6 × 10-5, 6.4 × 10-5, respectively) and diolein (p = 2.2 × 10-6, 5.9 × 10-6), and waist circumference with d-glucosamine-6-phosphate (p = 1.8 × 10-4). CONCLUSION: In the context of cardiometabolic health, aging, and disease, these results highlight key diet-derived metabolites that are central to specific rate-limited processes that are linked to cardiometabolic health. These metabolites include acetate and diacylglycerol, pertinent to blood pressure and triglycerides, respectively, as well as diacylglycerol and HDL-cholesterol.

Characterisation of Fasting and Postprandial NMR Metabolites: Insights from the ZOE PREDICT 1 Study.

BACKGROUND: Postprandial metabolomic profiles and their inter-individual variability are not well characterised. Here, we describe postprandial metabolite changes, their correlations with fasting values and their inter- and intra-individual variability, following a standardised meal in the ZOE PREDICT 1 cohort. METHODS: In the ZOE PREDICT 1 study (n = 1002 (NCT03479866)), 250 metabolites, mainly lipids, were measured by a Nightingale NMR panel in fasting and postprandial (4 and 6 h after a 3.7 MJ mixed nutrient meal, with a second 2.2 MJ mixed nutrient meal at 4 h) serum samples. For each metabolite, inter- and intra-individual variability over time was evaluated using linear mixed modelling and intraclass correlation coefficients (ICC) were calculated. RESULTS: Postprandially, 85% (of 250 metabolites) significantly changed from fasting at 6 h (47% increased, 53% decreased; Kruskal-Wallis), with 37 measures increasing by >25% and 14 increasing by >50%. The largest changes were observed in very large lipoprotein particles and ketone bodies. Seventy-one percent of circulating metabolites were strongly correlated (Spearman's rho >0.80) between fasting and postprandial timepoints, and 5% were weakly correlated (rho <0.50). The median ICC of the 250 metabolites was 0.91 (range 0.08-0.99). The lowest ICCs (ICC <0.40, 4% of measures) were found for glucose, pyruvate, ketone bodies (ß-hydroxybutyrate, acetoacetate, acetate) and lactate. CONCLUSIONS: In this large-scale postprandial metabolomic study, circulating metabolites were highly variable between individuals following sequential mixed meals. Findings suggest that a meal challenge may yield postprandial responses divergent from fasting measures, specifically for glycolysis, essential amino acid, ketone body and lipoprotein size metabolites.

Omega-3 fatty acids and individual variability in plasma triglyceride response: A mini-review.

Cardiovascular disease (CVD) is a leading cause of death worldwide. Supplementation with the marine omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) is associated with lower CVD risk. However, results from randomized controlled trials that examine the effect of omega-3 supplementation on CVD risk are inconsistent. This risk-reducing effect may be mediated by reducing inflammation, oxidative stress and serum triglyceride (TG) levels. However, not all individuals respond by reducing TG levels after omega-3 supplementation. This inter-individual variability in TG response to omega-3 supplementation is not fully understood. Hence, we aim to review the evidence for how interactions between omega-3 fatty acid supplementation and genetic variants, epigenetic and gene expression profiling, gut microbiota and habitual intake of omega-3 fatty acids can explain why the TG response differs between individuals. This may contribute to understanding the current controversies and play a role in defining future personalized guidelines to prevent CVD.

Changes in quantity plant-based protein intake on type 2 diabetes remission in coronary heart disease patients: from the CORDIOPREV study.

PURPOSE: Diabetes remission is a phenomenon described in the context of drastic weight loss due to bariatric surgery or low-calorie diets. Evidence suggests that increasing the intake of plant protein could reduce the risk of type 2 diabetes. We sought for association between changes in plant protein intake in the context of 2 healthy diets without weight loss nor glucose-lowering medication, and diabetes remission in coronary heart disease patients from the CORDIOPREV study. METHODS: Newly diagnosed type 2 diabetes participants without glucose-lowering treatment were randomized to consume a Mediterranean or a low-fat diet. Type 2 diabetes remission was assessed with a median follow-up of 60 months according to the ADA recommendation. Information on patient's dietary intake was collected using food-frequency questionnaires. At first year of intervention, 177 patients were classified according to changes in plant protein consumption into those who increased or decreased its intake, in order to perform an observational analysis on the association between protein intake and diabetes remission. RESULTS: Cox regression showed that patients increasing plant protein intake were more likely to remit from diabetes than those who decreased its intake (HR = 1.71(1.05-2.77)). The remission occurred mainly at first and second year of follow-up with diminished number of patients achieving remission in the third year onwards. The increase in plant protein was associated with lower intake of animal protein, cholesterol, saturated fatty acids, and fat, and with higher intake of whole grains, fibre, carbohydrates, legumes, and tree nuts. CONCLUSION: These results support the need to increase protein intake of vegetal origin as dietary therapy to reverse type 2 diabetes in the context of healthy diets without weight loss.

The impact of alcoholic drinks and dietary factors on epigenetic markers associated with triglyceride levels.

Background: Many epigenetic loci have been associated with plasma triglyceride (TG) levels, but epigenetic connections between those loci and dietary exposures are largely unknown. This study aimed to characterize the epigenetic links between diet, lifestyle, and TG. Methods: We first conducted an epigenome-wide association study (EWAS) for TG in the Framingham Heart Study Offspring population (FHS, n = 2,264). We then examined relationships between dietary and lifestyle-related variables, collected four times in 13 years, and differential DNA methylation sites (DMSs) associated with the last TG measures. Third, we conducted a mediation analysis to evaluate the causal relationships between diet-related variables and TG. Finally, we replicated three steps to validate identified DMSs associated with alcohol and carbohydrate intake in the Genetics of Lipid-Lowering Drugs and Diet Network (GOLDN) study (n = 993). Results: In the FHS, the EWAS revealed 28 TG-associated DMSs at 19 gene regions. We identified 102 unique associations between these DMSs and one or more dietary and lifestyle-related variables. Alcohol and carbohydrate intake showed the most significant and consistent associations with 11 TG-associated DMSs. Mediation analyses demonstrated that alcohol and carbohydrate intake independently affect TG via DMSs as mediators. Higher alcohol intake was associated with lower methylation at seven DMSs and higher TG. In contrast, increased carbohydrate intake was associated with higher DNA methylation at two DMSs (CPT1A and SLC7A11) and lower TG. Validation in the GOLDN further supports the findings. Conclusion: Our findings imply that TG-associated DMSs reflect dietary intakes, particularly alcoholic drinks, which could affect the current cardiometabolic risk via epigenetic changes. This study illustrates a new method to map epigenetic signatures of environmental factors for disease risk. Identification of epigenetic markers of dietary intake can provide insight into an individual's risk of cardiovascular disease and support the application of precision nutrition. Clinical Trial Registration: www.ClinicalTrials.gov, the Framingham Heart Study (FHS), NCT00005121; the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN), NCT01023750.

DNA-Methylation Signatures of Tobacco Smoking in a High Cardiovascular Risk Population: Modulation by the Mediterranean Diet.

Biomarkers based on DNA methylation are relevant in the field of environmental health for precision health. Although tobacco smoking is one of the factors with a strong and consistent impact on DNA methylation, there are very few studies analyzing its methylation signature in southern European populations and none examining its modulation by the Mediterranean diet at the epigenome-wide level. We examined blood methylation smoking signatures on the EPIC 850 K array in this population (n = 414 high cardiovascular risk subjects). Epigenome-wide methylation studies (EWASs) were performed analyzing differential methylation CpG sites by smoking status (never, former, and current smokers) and the modulation by adherence to a Mediterranean diet score was explored. Gene-set enrichment analysis was performed for biological and functional interpretation. The predictive value of the top differentially methylated CpGs was analyzed using receiver operative curves. We characterized the DNA methylation signature of smoking in this Mediterranean population by identifying 46 differentially methylated CpGs at the EWAS level in the whole population. The strongest association was observed at the cg21566642 (p = 2.2 × 10-32) in the 2q37.1 region. We also detected other CpGs that have been consistently reported in prior research and discovered some novel differentially methylated CpG sites in subgroup analyses. In addition, we found distinct methylation profiles based on the adherence to the Mediterranean diet. Particularly, we obtained a significant interaction between smoking and diet modulating the cg5575921 methylation in the AHRR gene. In conclusion, we have characterized biomarkers of the methylation signature of tobacco smoking in this population, and suggest that the Mediterranean diet can increase methylation of certain hypomethylated sites.

Dietary Responses of Dementia-Related Genes Encoding Metabolic Enzymes.

The age-related loss of the cognitive function is a growing concern for global populations. Many factors that determine cognitive resilience or dementia also have metabolic functions. However, this duality is not universally appreciated when the action of that factor occurs in tissues external to the brain. Thus, we examined a set of genes involved in dementia, i.e., those related to vascular dementia, Alzheimer's disease, Parkinson's disease, and the human metabolism for activity in 12 metabolically active tissues. Mining the Genotype-Tissue Expression (GTEx) data showed that most of these metabolism-dementia (MD) genes (62 of 93, 67%) exhibit a higher median expression in any of the metabolically active tissues than in the brain. After identifying that several MD genes served as blood-based biomarkers of longevity in other studies, we examined the impact of the intake of food, nutrients, and other dietary factors on the expression of MD genes in whole blood in the Framingham Offspring Study (n = 2134). We observed positive correlations between flavonoids and HMOX1, taurine and UQCRC1, broccoli and SLC10A2, and myricetin and SLC9A8 (p < 2.09 × 10-4). In contrast, dairy protein, palmitic acid, and pie were negatively correlated, respectively, with the expression of IGF1R, CSF1R, and SLC9A8, among others (p < 2.92 × 10-4). The results of this investigation underscore the potential contributions of metabolic enzyme activity in non-brain tissues to the risk of dementia. Specific epidemiological or intervention studies could be designed using specific foods and nutrients or even dietary patterns focused on these foods and nutrients that influence the expression of some MD genes to verify the findings presented here.

A metabolomic signature of the APOE2 allele.

With the goal of identifying metabolites that significantly correlate with the protective e2 allele of the apolipoprotein E (APOE) gene, we established a consortium of five studies of healthy aging and extreme human longevity with 3545 participants. This consortium includes the New England Centenarian Study, the Baltimore Longitudinal Study of Aging, the Arivale study, the Longevity Genes Project/LonGenity studies, and the Long Life Family Study. We analyzed the association between APOE genotype groups E2 (e2e2 and e2e3 genotypes, N = 544), E3 (e3e3 genotypes, N = 2299), and E4 (e3e4 and e4e4 genotypes, N = 702) with metabolite profiles in the five studies and used fixed effect meta-analysis to aggregate the results. Our meta-analysis identified a signature of 19 metabolites that are significantly associated with the E2 genotype group at FDR < 10%. The group includes 10 glycerolipids and 4 glycerophospholipids that were all higher in E2 carriers compared to E3, with fold change ranging from 1.08 to 1.25. The organic acid 6-hydroxyindole sulfate, previously linked to changes in gut microbiome that were reflective of healthy aging and longevity, was also higher in E2 carriers compared to E3 carriers. Three sterol lipids and one sphingolipid species were significantly lower in carriers of the E2 genotype group. For some of these metabolites, the effect of the E2 genotype opposed the age effect. No metabolites reached a statistically significant association with the E4 group. This work confirms and expands previous results connecting the APOE gene to lipid regulation and suggests new links between the e2 allele, lipid metabolism, aging, and the gut-brain axis.

Metabolomic profiling in dogs with dilated cardiomyopathy eating non-traditional or traditional diets and in healthy controls.

Dilated cardiomyopathy (DCM), caused by genetic and environmental factors, usually progresses to heart failure, a major cause of death in elderly people. A diet-associated form of DCM was recently identified in pet dogs eating non-traditional (NT) diets. To identify potential dietary causes, we analyzed metabolomic signatures and gene set/pathway enrichment in (1) all dogs based on disease, diet, and their interactions and (2) dogs with DCM based on diet. Metabolomic analysis was performed in 38 dogs with DCM eating NT diets (DCM-NT), 8 dogs with DCM eating traditional diets, 12 healthy controls eating NT diets, and 17 healthy controls eating traditional diets. Overall, 153 and 63 metabolites differed significantly between dogs with DCM versus healthy controls and dogs eating NT versus traditional diets, respectively, with 12 metabolites overlapping both analyses. Protein-protein interaction networks and gene set enrichment analysis identified 105 significant pathways and gene sets including aging-related pathways (e.g., nuclear factor-kappa B, oxidative damage, inflammation). Seventeen metabolites differed significantly in dogs with DCM eating NT versus traditional diets (e.g., fatty acids, amino acids, legume biomarkers), suggesting different mechanisms for primary versus diet-associated DCM. Our multifaceted metabolomic assessment of DCM in dogs highlighted diet's role in some forms of DCM.

APOE Genotypes Modulate Inflammation Independently of Their Effect on Lipid Metabolism.

The association between APOE genotypes and cardiovascular disease (CVD) is partially mediated by LDL-cholesterol concentration but persists after adjusting for lipid levels and other cardiovascular risk factors. Data from the Aragon Workers Health Study (AWHS) (n = 4159) and the Lipid Unit at the Hospital Universitario Miguel Servet (HUMS) (n = 3705) were used to investigate the relationship between C-reactive protein (CRP) levels and APOE genotype. Lipoprotein particle and GlycA concentrations were analyzed in a subsample from AWHS. APOE genotyping was carried out by the Sanger method in both cohorts. APOE4 carriers had significantly lower levels of CRP than APOE3 carriers. Furthermore, APOE4 carriers had cholesterol-enriched LDL particles compared to APOE2 carriers. APOE4 carriers also had higher concentrations of small, medium, and large LDL particles. CRP levels were not associated with lipoprotein particle number, size, or composition. GlycA levels were not associated with APOE genotypes. However, GlycA levels were significantly associated with the size and the amount of cholesterol contained in HDL, VLDL, and LDL particles. APOE genotype influences CRP concentration regardless of lipid profile. APOE2 carriers showed the highest CRP levels, followed by APOE3 and APOE4. A more atherogenic lipid profile, but not inflammatory markers could partly explain the higher CVD risk observed in APOE4 carriers.