Global DNA Hypomethylation Is Associated with High Serum-Persistent Organic Pollutants in Greenlandic Inuit

Background

Persistent organic pollutants (POPs) may influence epigenetic mechanisms; therefore, they could affect chromosomal stability and gene expression. DNA methylation, an epigenetic mechanism, has been associated with cancer initiation and progression. Greenlandic Inuit have some of the highest reported POP levels worldwide.

Objective

Our aim in this study was to evaluate the relationship between plasma POPs concentrations and global DNA methylation (percent 5-methylcytosine) in DNA extracted from blood samples from 70 Greenlandic Inuit. Blood samples were collected under the Arctic Monitoring and Assessment Program and previously analyzed for a battery of POPs.

Methods

We used pyrosequencing to estimate global DNA methylation via Alu and LINE-1 assays of bisulfite-treated DNA. We investigated correlations between plasma POP concentrations and global DNA methylation via correlation coefficients and linear regression analyses.

Results

We found inverse correlations between percents methylcytosine and many of the POP concentrations measured. Linear regressions, adjusting for age and cigarette smoking, showed statistically significant inverse linear relationships mainly for the Alu assay for p,p′-DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane; β = −0.26), p,p′-DDE [1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene; β = −0.38], β-hexachlorocyclohexane (β = −0.48), oxychlordane (β = −0.32), α-chlordane (β = −0.75), mirex (β = −0.27), sum of polychlorinated biphenyls (β = −0.56), and sum of all POPs (β = −0.48). Linear regressions for the LINE-1 assay showed β estimates of similar magnitudes to those using the Alu assay, however, none was statistically significant.

Conclusions

This is the first study to investigate environmental exposure to POPs and DNA methylation levels in a human population. Global methylation levels were inversely associated with blood plasma levels for several POPs and merit further investigation.     

Association of Testosterone-Related Dietary Pattern with Testicular Function among Adult Men: A Cross-Sectional Health Screening Study in Taiwan

Diets could play an important role in testicular function, but studies on how adherence to the dietary patterns influences human testicular function in Asian countries are scarce. Herein, we examined the association between testosterone-related dietary patterns and testicular function among adult men in Taiwan. This cross-sectional study recruited 3283 men who attended a private medical screening program from 2009 to 2015. Testosterone-related dietary pattern was generated by the reduced rank regression (RRR) method. The association between adherence to quartile of dietary pattern scores with sex hormones (testosterone, follicle-stimulating hormone (FSH), luteinizing hormone (LH), and estradiol (E2)) and sperm quality (sperm concentration (SC), total sperm motility (TSM), progressive motility (PRM), and normal sperm morphology (NSM)) were examined by multivariable linear regression. Hemoglobin (β = 0.57, p < 0.001), hematocrit (β = 0.17, p = 0.002), triglyceride (β = −0.84, p < 0.001), HDL-cholesterol (β = 3.58, p < 0.001), total cholesterol to HDL-cholesterol ratio (β = −0.78, p < 0.001), and uric acid (β = −10.77, p < 0.001) were highly correlated with testosterone levels. Therefore, these biomarkers were used to construct a testosterone-related dietary pattern. Highest adherence (Q4) to dietary pattern scores were negatively associated with lower testosterone in the pooled analysis (β = −0.89, p = 0.037) and normal-weight men (β = −1.48, p = 0.019). Likewise, men in the Q4 of the dietary pattern had lower SC (β = −5.55, p = 0.001) and NSM (β = −2.22, p = 0.007) regardless of their nutritional status. Our study suggesting that testosterone-related dietary pattern (rich in preserved vegetables or processed meat or fish, deep-fried foods, innards organs, rice or flour products cooked in oil, and dipping sauce, but low in milk, dairy products, legumes, or beans, and dark or leafy vegetables) was associated with a poor testicular function.     

Dietary Fibre Intake in Type 2 and New-Onset Prediabetes/Diabetes after Acute Pancreatitis: A Nested Cross-Sectional Study

The association between intake of dietary fibre and glucose metabolism has been extensively investigated in numerous metabolic disorders. However, little is known about this association in individuals after an attack of acute pancreatitis (AP). The aim was to investigate the associations between intake of dietary fibre and markers of glucose metabolism in individuals with new-onset prediabetes or diabetes after acute pancreatitis (NODAP), pre-exiting type 2 prediabetes or diabetes, and normoglycaemia after acute pancreatitis. This cross-sectional study was nested within the parent prospective longitudinal cohort study. The studied markers of glucose metabolism were fasting plasma glucose and glycated haemoglobin. Habitual intake of dietary fibre was determined using the EPIC-Norfolk food frequency questionnaire. Multivariable linear regression analyses were conducted. The study included a total of 108 individuals after AP. In the NODAP group, increased intakes of total fibre (β = −0.154, p = 0.006), insoluble fibre (β = −0.133, p = 0.01), and soluble fibre (β = −0.13, p = 0.02) were significantly associated with a reduction in fasting plasma glucose. Increased intakes of vegetables (β = −0.069, p = 0.004) and nuts (β = −0.039, p = 0.038) were significantly associated with a reduction in fasting plasma glucose. Increased intake of nuts (β = −0.054, p = 0.001) was also significantly associated with a reduction in glycated haemoglobin. None of the above associations were significant in the other study groups. Habitual intake of dietary fibre was inversely associated with fasting plasma glucose in individuals with NODAP. Individuals after an attack of AP may benefit from increasing their intake of dietary fibre (specifically, vegetables and nuts) with a view to preventing NODAP.     

Genetic and Non-genetic Predictors of LINE-1 Methylation in Leukocyte DNA

Background: Altered DNA methylation has been associated with various diseases.Objective: We evaluated the association between levels of methylation in leukocyte DNA at long interspersed nuclear element 1 (LINE-1) and genetic and non-genetic characteristics of 892 control participants from the Spanish Bladder Cancer/EPICURO study.Methods: We determined LINE-1 methylation levels by pyrosequencing. Individual data included demographics, smoking status, nutrient intake, toenail concentrations of 12 trace elements, xenobiotic metabolism gene variants, and 515 polymorphisms among 24 genes in the one-carbon metabolism pathway. To assess the association between LINE-1 methylation levels (percentage of methylated cytosines) and potential determinants, we estimated beta coefficients (βs) by robust linear regression.Results: Women had lower levels of LINE-1 methylation than men (β = –0.7, p = 0.02). Persons who smoked blond tobacco showed lower methylation than nonsmokers (β = –0.7, p = 0.03). Arsenic toenail concentration was inversely associated with LINE-1 methylation (β = –3.6, p = 0.003). By contrast, iron (β = 0.002, p = 0.009) and nickel (β = 0.02, p = 0.004) were positively associated with LINE-1 methylation. Single nucleotide polymorphisms (SNPs) in DNMT3A (rs7581217-per allele, β = 0.3, p = 0.002), TCN2 (rs9606756-GG, β = 1.9, p = 0.008; rs4820887-AA, β = 4.0, p = 4.8 × 10^–7; rs9621049-TT, β = 4.2, p = 4.7 × 10^–9), AS3MT (rs7085104-GG, β = 0.7, p = 0.001), SLC19A1 (rs914238, TC vs. TT: β = 0.5 and CC vs. TT: β = –0.3, global p = 0.0007) and MTHFS (rs1380642, CT vs. CC: β = 0.3 and TT vs. CC; β = –0.8, global p = 0.05) were associated with LINE-1 methylation.Conclusions: We identified several characteristics, environmental factors, and common genetic variants that predicted DNA methylation among study participants.     

Role of Phytoestrogen-Rich Bioactive Substances (Linum usitatissimum L., Glycine max L., Trifolium pratense L.) in Cardiovascular Disease Prevention in Postmenopausal Women: A Systematic Review and Meta-Analysis

The aim of this report was to determine the impact of flaxseed, soy and red clover, and their bioactive substances on the lipid profile in postmenopausal women in cardiovascular diseases prevention. We used the following databases: MEDLINE (PubMed), EMBASE and the Cochrane Library. Meta-analysis indicates that the intake of flaxseed by postmenopausal women is associated with a statistically significant reduction in total cholesterol (TC) levels (weighted-mean difference (WMD) = −0.26; 95% confidence interval (95% CI): −0.38 to −0.13; p = 0.0001), low-density lipoprotein cholesterol (LDL-C) levels (WMD = −0.19; 95% CI: −0.30 to −0.08; p = 0.0006), and high-density lipoprotein cholesterol (HDL-C) levels (WMD = −0.06; 95% CI: −0.11 to −0.01; p = 0.0150). The effect of soy protein on the lipid profile showed a significant decrease in TC levels: WMD = −0.15; 95% CI: −0.25–0.05; p = 0.0048, LDL-C levels: WMD = −0.15; 95% CI: −0.25–0.05; p = 0.0067, as well as a significant increase in HDL-C levels: WMD = 0.05; 95% CI: 0.02–0.08; p = 0.0034. Changes in the lipid profile showed a significant reduction in TC levels after the use of red clover (WMD = −0.11; 95% CI: −0.18–−0.04; p = 0.0017) and a significant increase in HDL-C levels (WMD = 0.04; 95% CI: 0.01 to 0.07; p = 0.0165). This meta-analysis provides evidence that consuming flaxseed, soy and red clover can have a beneficial effect on lipids in postmenopausal women and suggest a favorable effect in preventing cardiovascular diseases.     

Dietary Glycemic Load and Plasma Amyloid-β Biomarkers of Alzheimer’s Disease

Previous studies have highlighted links between a high-glycemic-load (GL) diet and Alzheimer’s disease in apolipoprotein E ε4 (APOE4) carriers. However, the impact of high-GL diet on plasma amyloid-β (Aβ), an Alzheimer’s disease hallmark that can be detected decades before clinical symptomatology, is unknown. This study examined the association between plasma Aβ peptides (Aβ₄₀, Aβ₄₂ concentration and Aβ₄₂/Aβ₄₀ ratio) and GL. The influence of the GL of four meal types (breakfast, lunch, afternoon snack, and dinner) was also determined. From the prospective Three-City study, 377 participants with plasma Aβ measurements, and who completed the Food Frequency Questionnaire, were selected. The association between plasma Aβ and GL was tested using an adjusted linear regression model. Lunch GL was associated with a lower plasma Aβ₄₂ concentration (β = −2.2 [CI = −4.27, −0.12], p = 0.038) and lower Aβ₄₂/Aβ₄₀ ratio (β = −0.009 [CI = −0.0172, −0.0007], p = 0.034) in the model adjusted for center, age, sex, education level, APOE4 status, energy intake, serum creatinine, total cholesterol, and Mediterranean-like diet. No significant association was found with the GL of the other meal types. These results suggest that dietary GL may independently modulate the plasma Aβ of the APOE4 status. The mechanism underlying diet, metabolic response, and Aβ peptide regulation must be elucidated.     

A Western Dietary Pattern Is Associated with Poor Academic Performance in Australian Adolescents

The aim of this study was to investigate cross-sectional associations between dietary patterns and academic performance among 14-year-old adolescents. Study participants were from the Western Australian Pregnancy Cohort (Raine) Study. A food frequency questionnaire was administered when the adolescents were 14 years old, and from the dietary data, a ‘Healthy’ and a ‘Western’ dietary pattern were identified by factor analysis. The Western Australian Literacy and Numeracy Assessment (WALNA) results from grade nine (age 14) were linked to the Raine Study data by The Western Australian Data Linkage Branch. Associations between the dietary patterns and the WALNA (mathematics, reading and writing scores) were assessed using multivariate linear regression models adjusting for family and socioeconomic characteristics. Complete data on dietary patterns, academic performance and covariates were available for individuals across the different analyses as follows: n = 779 for mathematics, n = 741 for reading and n = 470 for writing. Following adjustment, significant negative associations between the ‘Western’ dietary pattern and test scores for mathematics (β = −13.14; 95% CI: −24.57; −1.76); p = 0.024) and reading (β = −19.16; 95% CI: −29.85; −8.47; p ≤ 0.001) were observed. A similar trend was found with respect to writing (β = −17.28; 95% CI: −35.74; 1.18; p = 0.066). ANOVA showed significant trends in estimated means of academic scores across quartiles for both the Western and Healthy patterns. Higher scores for the ‘Western’ dietary pattern are associated with poorer academic performance in adolescence.     

The Effect of Resveratrol on Blood Lipid Profile: A Dose-Response Meta-Analysis of Randomized Controlled Trials

(1) Background: The effects of resveratrol on blood lipids are controversial. Whether there is a dose-response of the lipid profile upon resveratrol supplementation is unknown. (2) Methods: This dose-response meta-analysis of randomized controlled trials (RCTs) was performed to explore the effects of resveratrol supplementation on lipid profile. A systematical and comprehensive search of several databases was conducted by 30 June 2022. (3) Results: The results indicated that the intake of resveratrol could significantly decrease the total cholesterol (TC) (mean difference = −10.28; 95%CI: −13.79, −6.76, p < 0.001), triglyceride (TG) (Mean difference = −856; 95%CI: −12.37, −4.75, p < 0.001) and low-density lipoprotein cholesterol (LDL-C) (mean difference = −5.69; 95%CI: −11.07, −0.31, p = 0.038) level, but did not alter the level of high-density lipoprotein cholesterol (HDL-C). In the non-linear dose–response analysis, we observed a significant effect of the supplementation dosage on the level of LDL-C (p-nonlinearity = 0.002). Results from the sub-group analysis showed that the reduction of LDL-C was more significant in the trials with a duration of ≥12 weeks and in subjects with type 2 diabetes mellitus. (4) Conclusion: Findings from this study suggest that resveratrol may be beneficial to reduce TC, TG, and LDL-C levels in the blood. The dosage of the resveratrol intervention is an essential factor that affects the level of LDL-C.     

Energy-Adjusted Dietary Intakes Are Associated with Perceived Barriers to Healthy Eating but Not Food Insecurity or Sports Nutrition Knowledge in a Pilot Study of ROTC Cadets

Military service is inherently demanding and, due to the nature of these demands, the term “tactical athlete” has been coined to capture the physical requirements of the profession. Reserve Officers’ Training Corps (ROTC) cadets are a unique subset of the military service community, and the complexity of their training and educational pursuits increases their susceptibility to unhealthy eating patterns. The purpose of this pilot study was to explore the relationship between the perceived barriers to healthy eating, food insecurity, sports nutrition knowledge, and dietary patterns among Army ROTC cadets. The usual dietary intake was gathered from (N = 37) cadets using the General Nutrition Assessment Food Frequency Questionnaire. The perceived barriers to healthy eating were measured using a set of scales consisting of social barriers (6 items, α = 0.86), access barriers (2 items, α = 0.95), and personal barriers (2 items, α = 0.67), with higher-scale scores indicating greater perceived barriers. Spearman correlation coefficients were used to measure the association between the energy-adjusted dietary intakes and the scores on the barriers scales. Energy-adjusted intakes of calcium (ρ = −0.47, p ≤ 0.01), fiber (ρ = −0.35, p = 0.03), vitamin A (ρ = −0.46, p ≤ 0.01), vitamin C (ρ = −0.43, p ≤ 0.01), fruit (ρ = −0.34, p = 0.04), and vegetables (ρ = −0.50, p ≤ 0.01) were negatively correlated with the perceived personal barrier scores. The energy-adjusted intakes of fiber (ρ = −0.36, p = 0.03), vitamin C (ρ = −0.37, p = 0.03), and vitamin E (ρ = −0.45, p ≤.01) were negatively correlated with perceived social barriers, while energy-adjusted vitamin C intake was negatively correlated with perceived access barriers (ρ = −0.40, p = 0.01). Although additional research is needed to better understand the dietary patterns of ROTC cadets, among the participants in this study, greater perceived personal, social, and access barriers were associated with less nutrient-dense eating patterns. Interventions aimed at addressing such barriers may prove beneficial for the improvement of diet quality among ROTC cadets.     

A 60-Day Green Tea Extract Supplementation Counteracts the Dysfunction of Adipose Tissue in Overweight Post-Menopausal and Class I Obese Women

Menopause is characterized by weight gain and increased visceral fat, which acts as an endocrine organ secreting proinflammatory adipocytokines, with consequent increased risk of metabolic disorders. The aim of this double-blind, placebo-controlled randomized trial was to evaluate the effects of a 60-day dietary supplementation using Camellia sinensis leaf extract on adipose tissue dysfunction in overweight or class I obese post-menopausal, sedentary women. Primary endpoints were the respiratory quotient (RQ), the percentage of carbohydrates (%CHO), the percentage of fat oxidation (%FAT), and the resting energy expenditure (REE) measured by indirect calorimetry. Secondary endpoints included body composition, by dual x-ray absorptiometry (DXA), glucose profile, lipid profile, inflammatory state, liver and kidney function, hormonal status regarding satiety, and status of catecholamines. Twenty-eight women were randomized into two groups: 14 (BMI 31.1 ± 3.5) were supplemented and 14 (BMI 31.9 ± 2.2) received placebo. In regards to the between-group differences over time (β), a statistically significant difference between the supplemented and placebo group was observed for: RQ (β = −0.04, p = 0.009), % fat oxidation (β = 11.04, p = 0.0006), insulin (β = −1.74, p = 0.009), HOMA (β = −0.31, p = 0.02), waist circumference (β = −1.07, p = 0.007), REE (β = 83.21, p = 0.009), and CRP (β = −0.14, p = 0.02). These results demonstrate that a 60-day green tea extract supplementation counteracts the dysfunction of adipose tissue in overweight post-menopausal and class I obese women.     

Influence of Diet and Levels of Zonulin,Lipopolysaccharide and C-Reactive Protein on Cardiometabolic Risk Factors in Young Subjects

A western diet and increased intestinal permeability may contribute to systemic inflammation and the development of cardio-metabolic alterations. The aim of this study was to assess the relationship between diet, biomarkers of intestinal permeability, and chronic low-grade inflammation on the cardiometabolic profile. A cross-sectional study was carried out in 238 young subjects aged 18–29 years, divided into two groups: with <3 cardiometabolic risk factors (CRF) and ≥3 risk factors. Anthropometric parameters, biochemical profile, and serum levels of zonulin, lipopolysaccharide (LPS), and high-sensitivity C-reactive protein (hs-CRP) were measured, and the macronutrient intake was evaluated. Interaction models showed elevated glucose levels in the presence of high biomarker levels: zonulin ≥51.6 ng/mL plus LPS ≥ 1.35 EU/mL (β = 1.1, p = 0.006), and LPS ≥1.35 EU/mL plus hs-CRP ≥ 4.3 mg/L (β = 1.2, p = 0.007). In addition, triglyceride levels increased in the presence of LPS ≥ 1.35 EU/mL and hs-CRP ≥ 4.3 mg/L (β = 3.9, p = 0.01). Despite having increased biomarker levels, a higher consumption of water (≥2100 mL), polyunsaturated fatty acids (≥6.0 g), or fiber (≥30 g) decreased triglyceride (β = −9.6, p = 0.03), total cholesterol (β = −5.1, p = 0.01), and LDL-C levels (β = −7.7, p = 0.01). These findings suggest that the increased consumption of water, PUFA and fiber may improve lipid profile in subjects with intestinal permeability dysfunction or low-grade systemic inflammation.     

Habitual Dietary Fiber Intake,Fecal Microbiota,and Hemoglobin A1c Level in Chinese Patients with Type 2 Diabetes

High-fiber diet interventions have been proven to be beneficial for gut microbiota and glycemic control in diabetes patients. However, the effect of a low level of fiber in habitual diets remains unclear. This study aims to examine the associations of habitual dietary fiber intake with gut microbiome profiles among Chinese diabetes patients and identify differential taxa that mediated associations of dietary fiber with HbA1c level. Two cross-sectional studies and one longitudinal study were designed based on two follow-up surveys in a randomized trial conducted during 2015–2017. The study included 356 and 310 participants in the first and second follow-ups, respectively, with 293 participants in common in both surveys. Dietary fiber intake was calculated based on a 3-day 24-h diet recall at each survey and was classified into a lower or a higher group according to the levels taken based on the two surveys using 7.2 g/day as a cut-off value. HbA1c was assayed to assess glycemic status using a cut-off point of 7.0% and 8.0%. Microbiome was profiled by 16S rRNA sequencing. A high habitual dietary fiber intake was associated with a decrease in α-diversity in both the cross-sectional and longitudinal analyses. At the first follow–up, phylum Firmicutes and Fusobacteria were negatively associated with a higher dietary fiber intake (p < 0.05, Q < 0.15); at the second follow-up, genus Adlercreutzia, Prevotella, Ruminococcus, and Desulfovibrio were less abundant in patients taking higher dietary fiber (p < 0.05, Q < 0.15); genus Desulfovibrio and Ruminococcaceae (Unknown), two identified differential taxa by HbA1c level, were negatively associated with dietary fiber intake in both the cross-sectional and longitudinal analyses, and mediated the dietary fiber-HbA1c associations among patients taking dietary fiber ≥ 7.2 g/day (mediation effect β [95%CI]: −0.019 [−0.043, −0.003], p = 0.018 and −0.019 [−0.046, −0.003], p = 0.016). Our results suggest that habitual dietary fiber intake has a beneficial effect on gut microbiota in Chinese diabetes patients. Further studies are needed to confirm our results.     

Efficacy and Safety of Armolipid Plus®: An Updated PRISMA Compliant Systematic Review and Meta-Analysis of Randomized Controlled Clinical Trials

Armolipid Plus^® is a multi-constituent nutraceutical that claims to improve lipid profiles. The aim of this PRISMA compliant systematic review and meta-analysis was to globally evaluate the efficacy and safety of Armolipid Plus^® on the basis of the available randomized, blinded, controlled clinical trials (RCTs). A systematic literature search in several databases was conducted in order to identify RCTs assessing the efficacy and safety of dietary supplementation with Armolipid Plus^®. Two review authors independently identified 12 eligible studies (1050 included subjects overall) and extracted data on study characteristics, methods, and outcomes. Meta-analysis of the data suggested that dietary supplementation with Armolipid Plus^® exerted a significant effect on body mass index (mean difference (MD) = −0.25 kg/m², p = 0.008) and serum levels of total cholesterol (MD = −25.07 mg/dL, p < 0.001), triglycerides (MD = −11.47 mg/dL, p < 0.001), high-density lipoprotein cholesterol (MD = 1.84 mg/dL, p < 0.001), low-density lipoprotein cholesterol (MD = −26.67 mg/dL, p < 0.001), high sensitivity C reactive protein (hs-CRP, MD = −0.61 mg/L, p = 0.022), and fasting glucose (MD = −3.52 mg/dL, p < 0.001). Armolipid Plus^® was well tolerated. This meta-analysis demonstrates that dietary supplementation with Armolipid Plus^® is associated with clinically meaningful improvements in serum lipids, glucose, and hs-CRP. These changes are consistent with improved cardiometabolic health.     

ApoE4 Is Associated with Lower Body Mass,Particularly Fat Mass,in Older Women with Cognitive Impairment

A lower body mass is associated with the progression of Alzheimer’s disease (AD) and the risk of mortality in patients with AD; however, evidence of genetic determinants of decreased body mass in cognitively impaired older adults is limited. We therefore investigated the genetic effect of APOE-ε4 on body composition in older adults with mild cognitive impairment (MCI) and early-to-moderate-stage AD. A total of 1631 outpatients (aged 65–89 years) with MCI and early-to-moderate-stage AD were evaluated for the association between body composition and APOE-ε4 status. After adjusting for covariates, including cognitive function evaluated with the Mini-Mental State Examination, the presence of the APOE-ε4 was associated with lower weight (β = −1.116 ± 0.468 kg per presence, p = 0.017), fat mass (β = −1.196 ± 0.401 kg per presence, p = 0.003), and percentage of body fat (β = −1.700 ± 0.539% per presence, p = 0.002) in women but not in men. Additionally, the impact of APOE-ε4 on measures of body composition in women was more remarkable in MCI than in AD patients. The presence of the APOE-ε4 allele was associated with lower fat mass, particularly in women with MCI, independent of cognitive decline.     

Biomarkers of Lead Exposure and DNA Methylation within Retrotransposons

Background

DNA methylation is an epigenetic mark that regulates gene expression. Changes in DNA methylation within white blood cells may result from cumulative exposure to environmental metals such as lead. Bone lead, a marker of cumulative exposure, may therefore better predict DNA methylation than does blood lead.

Objective

In this study we compared associations between lead biomarkers and DNA methylation.

Methods

We measured global methylation in participants of the Normative Aging Study (all men) who had archived DNA samples. We measured patella and tibia lead levels by K-X-Ray fluorescence and blood lead by atomic absorption spectrophotometry. DNA samples from blood were used to determine global methylation averages within CpG islands of long interspersed nuclear elements-1 (LINE-1) and Alu retrotransposons. A mixed-effects model using repeated measures of Alu or LINE-1 as the dependent variable and blood/bone lead (tibia or patella in separate models) as the primary exposure marker was fit to the data.

Results

Overall mean global methylation (± SD) was 26.3 ± 1.0 as measured by Alu and 76.8 ± 1.9 as measured by LINE-1. In the mixed-effects model, patella lead levels were inversely associated with LINE-1 (β = −0.25; p < 0.01) but not Alu (β = −0.03; p = 0.4). Tibia lead and blood lead did not predict global methylation for either Alu or LINE-1.

Conclusion

Patella lead levels predicted reduced global DNA methylation within LINE-1 elements. The association between lead exposure and LINE-1 DNA methylation may have implications for the mechanisms of action of lead on health outcomes, and also suggests that changes in DNA methylation may represent a biomarker of past lead exposure.     

The Personal Food Systems of Pre-Season NCAA Division 1 High-Contact,Low-Contact,and Non-Contact College Athletes

Previous research indicates that dietary habits may differ between athletes of different sports. In this cross-sectional study, we hypothesize meal frequency, food choices, and food preferences will significantly differ between contact types. The participants were athletes (n = 92; men: n = 57, body fat percent (BF%): 14.8 ± 8.4%, body mass index (BMI): 25.5 ± 5.5 kg·m⁻²; women: n = 36, BF%: 26.7 ± 7.3%, BMI: 22.3 ± 2.7 kg·m⁻²) from high-contact (HCS), low-contact (LCS), and non-contact (NCS) sports. Meal frequency, food preference, and food choice questionnaires assessed factors influencing dietary habits. Dual-energy X-ray absorptiometry (DXA) measured lean body mass, fat mass, and body fat. A GLM multivariate analysis was used with significance accepted at p < 0.05. Significant body composition differences were observed between genders (p < 0.001) and among sports (p < 0.001). Dinner (83.7%), lunch (67.4%), and breakfast (55.4%) were the most frequently eaten meals, followed by evening snack (17.8%), afternoon snack (15.2%), and morning snack (8.7%). Greater preferences for starches were observed for HCS (p = 0.04; η² = 0.07) and for a greater preference for vegetables was found for NCS (p = 0.02; η² = 0.09). Significant differences also existed in the importance of health (p = 0.04; η² = 0.07), weight control (p = 0.05; η² = 0.11), natural content (p = 0.04; η² = 0.07), and price (p = 0.04; η² = 0.07). These results support our hypothesis that food choices and food preferences differ between contact types. This may help sports dieticians create more individualized nutrition programs.     

Associations between Dietary Animal and Plant Protein Intake and Cardiometabolic Risk Factors—A Cross-Sectional Study in China Health and Nutrition Survey

Available data investigating the associations between dietary animal and plant protein intakes and cardiometabolic risk factors (CMRFs) among populations with habitual plant-based diets are heterogenous and limited in scope. The current study was to assess the associations between dietary animal and plant protein intakes and CMRFs, including lipid and lipoprotein profiles, glucose homeostasis biomarkers, low-grade chronic inflammatory biomarker and uric acid in Chinese adults. Data of 7886 apparently healthy adults were extracted from the China Health and Nutrition Survey 2009. Dietary protein (total, animal and plant) intakes were assessed with three consecutive 24 h dietary recalls, and CMRFs were measured with standard laboratory methods. Substituting 5% of energy intake from animal protein for carbohydrates was positively associated with total cholesterol, low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (non-HDL-C) and uric acid (all p < 0.05). Substituting 5% of energy intake from plant protein for carbohydrates was inversely associated with non-HDL-C and LDL-C:HDL-C ratio, and positively associated with HDL-C and glycated hemoglobin (all p < 0.05). Some of these associations varied in subgroup analyses by BMI, sex, age or region. There were no significant associations between animal or plant protein intakes and high-sensitivity C-reactive protein. The public health implication of these findings requires further investigation.     

PNPLA3 Genotype,Arachidonic Acid Intake,and Unsaturated Fat Intake Influences Liver Fibrosis in Hispanic Youth with Obesity

Non-alcoholic fatty liver disease impacts 15.2% of Hispanic adolescents and can progress to a build-up of scared tissue called liver fibrosis. If diagnosed early, liver fibrosis may be reversible, so it is necessary to understand risk factors. The aims of this study in 59 Hispanic adolescents with obesity were to: (1) identify potential biological predictors of liver fibrosis and dietary components that influence liver fibrosis, and (2) determine if the association between dietary components and liver fibrosis differs by PNPLA3 genotype, which is highly prevalent in Hispanic adolescents and associated with elevated liver fat. We examined liver fat and fibrosis, genotyped for PNPLA3 gene, and assessed diet via 24-h diet recalls. The prevalence of increased fibrosis was 20.9% greater in males, whereas participants with the GG genotype showed 23.7% greater prevalence. Arachidonic acid was associated with liver fibrosis after accounting for sex, genotype, and liver fat (β = 0.072, p = 0.033). Intakes of several dietary types of unsaturated fat have different associations with liver fibrosis by PNPLA3 genotype after accounting for sex, caloric intake, and liver fat. These included monounsaturated fat (β_CC/CG = −0.0007, β_GG = 0.03, p-value = 0.004), polyunsaturated fat (β_CC/CG = −0.01, β_GG = 0.02, p-value = 0.01), and omega-6 (β_CC/CG = −0.0102, β_GG = 0.028, p-value = 0.01). Results from this study suggest that reduction of arachidonic acid and polyunsaturated fatty acid intake might be important for the prevention of non-alcoholic fatty liver disease progression, especially among those with PNPLA3 risk alleles.     

Potential Benefits of Selenium Supplementation in Reducing Insulin Resistance in Patients with Cardiometabolic Diseases: A Systematic Review and Meta-Analysis

Background: Selenium is a trace element that has been reported to be effective in regulating glucose and lipid metabolism. However, there is conflicting evidence from different clinical trials of selenium supplementation in treating cardiometabolic diseases (CMDs). Objective: This meta-analysis aimed to identify the effects of selenium supplementation on insulin resistance, glucose homeostasis, and lipid profiles in patients with CMDs. Methods: Randomized controlled trials (RCTs) of selenium supplementation for treating CMDs were screened in five electronic databases. Insulin levels, homeostatic model assessment of insulin resistance (HOMA-IR), fasting plasma glucose (FPG), and glycosylated hemoglobin A1C (HbA1c) were defined as the primary outcome markers, and lipid profiles were considered the secondary outcome markers. Results: Ten studies involving 526 participants were included in the meta-analysis. The results suggested that selenium supplementation significantly reduced serum insulin levels (standardized men difference [SMD]: −0.53; 95% confidence interval [CI] [−0.84, −0.21], p = 0.001, I² = 68%) and HOMA-IR (SMD: −0.50, 95% CI [−0.86, −0.14], p = 0.006, I² = 75%) and increased high-density lipoprotein cholesterol (HDL-C) levels (SMD: 0.97; 95% CI [0.26, 1.68], p = 0.007, I² = 92%), but had no significant effect on FPG, total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and very low-density lipoprotein cholesterol (VLDL-C). Conclusion: Current evidence supports the beneficial effects of selenium supplementation on reducing insulin levels, HOMA-IR, and increasing HDL-C levels. Selenium supplementation may be an effective strategy for reducing insulin resistance in patients with CMDs. However, more high-quality clinical studies are needed to improve the certainty of our estimates.