Homocysteine, B vitamins, and cardiovascular disease: a Mendelian randomization study

Astrocyte modulation in cerebral ischemia-reperfusion injury: A promising therapeutic strategy

Cerebral ischemia-reperfusion injury (CIRI) poses significant challenges for drug development due to its complex pathogenesis. Astrocyte involvement in CIRI pathogenesis has led to the development of novel astrocyte-targeting drug strategies. To comprehensively review the current literature, we conducted a thorough analysis from January 2012 to December 2023, identifying 82 drugs aimed at preventing and treating CIRI. These drugs target astrocytes to exert potential benefits in CIRI, and their primary actions include modulation of relevant signaling pathways to inhibit neuroinflammation and oxidative stress, reduce cerebral edema, restore blood-brain barrier integrity, suppress excitotoxicity, and regulate autophagy. Notably, active components from traditional Chinese medicines (TCM) such as Salvia miltiorrhiza, Ginkgo, and Ginseng exhibit these important pharmacological properties and show promise in the treatment of CIRI. This review highlights the potential of astrocyte-targeted drugs to ameliorate CIRI and categorizes them based on their mechanisms of action, underscoring their therapeutic potential in targeting astrocytes.

Causal Associations of Environmental Pollution and Cardiovascular Disease: A Two-Sample Mendelian Randomization Study

Background

There is growing evidence that concentrations of environmental pollutants are previously associated with cardiovascular disease; however, it is unclear whether this association reflects a causal relationship.

Methods

We utilized a two-sample Mendelian randomization (MR) approach to investigate how environmental pollution affects the likelihood of developing cardiovascular disease. We primarily employed the inverse variance weighted (IVW) method. Additionally, to ensure the robustness of our findings, we conducted several sensitivity analyses using alternative methodologies. These included maximum likelihood, MR-Egger regression, weighted median method and weighted model methods.

Results

Inverse variance weighted estimates suggested that an SD increase in PM2.5 exposure increased the risk of heart failure (OR = 1.40, 95% CI 1.02-1.93, p = 0.0386). We found that an SD increase in PM10 exposure increased the risk of hypertension (OR = 1.45, 95% CI 1.02-2.05, p = 0.03598) and atrial fibrillation (OR = 1.41, 95% CI 1.03-1.94, p = 0.03461). Exposure to chemical or other fumes in a workplace was found to increase the risk of hypertension (OR = 3.08, 95% CI 1.40-6.78, p = 0.005218), coronary artery disease (OR = 1.81, 95% CI 1.00-3.26, p = 0.04861), coronary heart disease (OR = 3.15, 95% CI 1.21-8.16, p = 0.0183) and myocardial infarction (OR = 3.03, 95% CI 1.13-8.17, p = 0.02802).

Conclusion

This study reveals the causal relationship between air pollutants and cardiovascular diseases, providing new insights into the protection of cardiovascular diseases.

Cathepsins and Parkinson's disease: insights from Mendelian randomization analyses

Background

Parkinson's disease (PD), the second most prevalent neurodegenerative condition, has a multifaceted etiology. Cathepsin-cysteine proteases situated within lysosomes participate in a range of physiological and pathological processes, including the degradation of harmful proteins. Prior research has pointed towards a potential link between cathepsins and PD; however, the precise causal relationship between the cathepsin family and PD remains unclear.

Methods

This study employed univariate and multivariate Mendelian randomization (MR) analyses to explore the causal relationship between the nine cathepsins and Parkinson's disease (PD) risk. For the primary analysis, genome-wide association study (GWAS) summary statistics for the plasma levels of the nine cathepsins and PD was obtained from the INTERVAL study and the International Parkinson's Disease Genomics Consortium. GWAS for PD replication analysis were obtained from the FinnGen consortium, and a meta-analysis was performed for the primary and replication analyses to evaluate the association between genetically predicted cathepsin plasma levels and PD risk. After identifying significant MR estimates, genetic co-localization analyses were conducted to determine whether shared or distinct causal variants influenced both cathepsins and PD.

Results

Elevated cathepsin B levels were associated with a decreased risk of PD in univariate MR analysis (odds ratio [OR] = 0.890, 95% confidence interval [CI]: 0.831-0.954, pFDR = 0.009). However, there was no indication that PD affected cathepsin B levels (OR = 0.965, 95% CI: 0.858-1.087, p = 0.852). In addition, after adjusting for the remaining cathepsins, cathepsin B levels independently and significantly contributed to the reduced risk of PD in multivariate MR analysis (OR = 0.887, 95% CI: 0.823-0.957, p = 0.002). The results of the replication MR analysis with the FinnGen GWAS for PD (OR = 0.921, 95% CI: 0.860-0.987, p = 0.020) and meta-analysis (OR = 0.905, 95% CI: 0.862-0.951, p < 0.001) were consistent with those of the primary analysis. Colocalization analysis did not provide any evidence of a shared causal variant between cathepsins and PD (PP.H4.abf = 0.005).

Conclusion

This genetic investigation supports the hypothesis that cathepsin B exerts a protective effect against PD. The quantification of cathepsin B levels could potentially serve as a predictive biomarker for susceptibility to PD, providing new insights into the pathomechanisms of the disease and possible interventions.

Associations of total homocysteine and kidney function with all-cause and cause-specific mortality in hypertensive patients: a mediation and joint analysis

Plasma total homocysteine (tHcy) and kidney function are both associated with mortality risk, but the degree to which kidney function modifies the impact of tHcy on mortality remains unknown. This prospective cohort study included a total of 14,225 hypertensive adults. Cox proportional hazard regression was used to analyze the separate and combined association of tHcy and estimated glomerular filtration rate (eGFR) with all-cause and cause-specific mortality. Mediation analysis was conducted to explore the mediating effect of eGFR. During a median follow-up of 4.0 years, 805 deaths were identified, including 397 deaths from cardiovascular disease (CVD). There were significant, positive relationships of tHcy with all-cause mortality (per 5 μmol/L; HR: 1.09; 95% CI: 1.07, 1.11), CVD mortality (HR: 1.11; 95% CI: 1.08, 1.13), and non-CVD mortality (HR: 1.07; 95% CI: 1.04, 1.10). The proportions of eGFR mediating these relationships were 39.1%, 35.7%, and 49.7%, respectively. There were additive interactions between tHcy and eGFR. Compared with those with low tHcy (<15 μmol/L) and high eGFR (≥90 mL·min-1·1.73 m-2), participants with high tHcy (≥20 μmol/L) and low eGFR (<60 mL·min-1·1.73 m-2) had the highest risk of all-cause mortality (HR: 4.89; 95% CI: 3.81, 6.28), CVD mortality (HR: 5.80; 95% CI: 4.01, 8.40), and non-CVD mortality (HR: 4.25; 95% CI: 3.02, 5.97). In conclusion, among Chinese hypertensive adults, high tHcy and impaired kidney function were independently and jointly associated with higher risks of all-cause and cause-specific mortality. Importantly, kidney function explained most (nearly 40%) of the increased risk of mortality conferred by high tHcy.

Dietary vitamin B6 intake and stroke are negatively associated in adults: A cross-sectional study from the NHANES

Background

The relationship between dietary vitamin B6 and stroke risk is controversial; thus, we analyzed their correlation using data from the National Health and Nutrition Examination Survey (NHANES).

Method

Data from 2005 to 2018 were collected from the NHANES database. Two 24-h dietary recalls and a standard questionnaire were used to evaluate vitamin B6 intake and stroke prevalence. We used logistic regression models to estimate the association between dietary vitamin B6 intake and stroke risk and investigated the nonlinear relationship between them using a restricted cubic spline (RCS). Sensitivity analysis was conducted using propensity score matching (PSM).

Results

Among 24,214 participants, 921 were patients diagnosed with stroke, while 23,293 were without stroke. The multivariate logistic regression model revealed that individuals in the highest quartile of vitamin B6 consumption had a significantly lower stroke risk than those in the lowest quartile under the fully adjusted model (OR: 0.48, 95 % CI: 0.35-0.66, P < 0.001). Subgroup analyses showed that dietary intake of vitamin B6 was a significant protective factor against stroke risk in different populations, with the most pronounced effect in the population engaging in moderate-intensity physical activity (OR: 0.34, 95%CI: 0.20-0.57). The RCS models revealed a non-linear L-shaped relationship (P for nonlinearity = 0.006) between stroke and dietary intake of vitamin B6.

Conclusions

Our study shows that an increased intake of vitamin B6 could be an effective strategy in reducing the risk of stroke.

Association of c.+677 C>T (rs1801133) and c.+1298 A>C (rs1801131) MTHFR genetic variants with cardiometabolic and disease risk in systemic lupus erythematosus patients: A cross-sectional study

Systemic lupus erythematosus (SLE) patients present a high prevalence of cardiometabolic risk, associated with worse clinical manifestations and mortality. Folate, an essential micronutrient that participates in vital immune cellular functions, could positively affect the cardiometabolic and disease risk in SLE, through the methylenetetrahydrofolate reductase (MTHFR) enzyme, which participates in the folate metabolism, where single nucleotide variants (SNVs) have been described as a potential genetic risk factor for SLE. The aim of this study was to determine the association of the c.+677 C>T (rs1801133) and c.+1298 A>C (rs1801131) MTHFR genetic variants with cardiometabolic risk and clinical disease variables in SLE patients. A case-control study was conducted on 394 unrelated Mexican-mestizo women: 199 with SLE according to the 1997 SLE-ACR criteria and 196 control subjects (CS). Folic acid and homocysteine levels were evaluated by immunoassays. Genotyping of MTHFR genetic variants was carried out by allelic discrimination. No significant differences were found for folic acid (p = .15) and homocysteine serum levels (p = .59) between groups. According to the CC c.+677 MTHFR genotype, this was associated with low cardiovascular disease (CVD) risk by the Castelli index (OR = 0.42; p = .03) in SLE patients. The TC (OR = 1.3; p = .03) and the TA (OR = 1.6; p < .01) haplotypes from c.+677 C>T plus c.+1298 MTHFR were associated with SLE risk, while the CC MTHFR haplotype (OR = 0.5; p = .01) was found as a non-risk factor for the disease. In conclusion, the TC and the TA MTHFR haplotypes are associated with disease risk; meanwhile, the CC c.+677 MTHFR genotype confers lower cardiometabolic risk in Mexican-mestizo SLE patients.

Influence of maternal folate depletion on Art3 DNA methylation in the murine adult brain; potential consequences for brain and neurocognitive health

The developmental origins of health and disease hypothesis suggest early-life environment impacts health outcomes throughout the life course. In particular, epigenetic marks, including DNA methylation, are thought to be key mechanisms through which environmental exposures programme later-life health. Adequate maternal folate status before and during pregnancy is essential in the protection against neural tube defects, but data are emerging that suggest early-life folate exposures may also influence neurocognitive outcomes in childhood and, potentially, thereafter. Since folate is key to the supply of methyl donors for DNA methylation, we hypothesize that DNA methylation may be a mediating mechanism through which maternal folate influences neurocognitive outcomes. Using bisulphite sequencing, we measured DNA methylation of five genes (Art3, Rsp16, Tspo, Wnt16, and Pcdhb6) in the brain tissue of adult offspring of dams who were depleted of folate (n = 5, 0.4 mg folic acid/kg diet) during pregnancy (~19-21 days) and lactation (mean 22 days) compared with controls (n = 6, 2 mg folic acid/kg diet). Genes were selected as methylation of their promoters had previously been found to be altered by maternal folate intake in mice and humans across the life course, and because they have potential associations with neurocognitive outcomes. Maternal folate depletion was significantly associated with Art3 gene hypomethylation in subcortical brain tissue of adult mice at 28 weeks of age (mean decrease 6.2%, P = .03). For the other genes, no statistically significant differences were found between folate depleted and control groups. Given its association with neurocognitive outcomes, we suggest Art3 warrants further study in the context of lifecourse brain health. We have uncovered a potential biomarker that, once validated in accessible biospecimens and human context, may be useful to track the impact of early-life folate exposure on later-life neurocognitive health, and potentially be used to develop and monitor the effects of interventions.

Prevalence and determinants of micronutrient deficiencies in malnourished older hospitalized patients

BACKGROUND AND OBJECTIVE

Malnutrition and micronutrient deficiencies represent significant concerns in geriatric care, leading to adverse health outcomes in older adults. The study aimed to investigate the prevalence and determinants of micronutrient deficiencies in malnourished older hospitalized patients.

DESIGN AND SETTING

This prospective, observational study was conducted in a geriatric acute care unit.

PARTICIPANTS

The study included 156 malnourished older adults.

MEASUREMENTS

Malnutrition was identified using the Mini Nutritional Assessment-Short Form. Micronutrient status was assessed through serum analysis of vitamins (A, B1, B6, B12, C, D, E, H, K, folic acid) and minerals (iron, zinc, copper, selenium) within 24 h post-admission.

RESULTS

The average patient age was 82.3 ± 7.5 years, with 69% female. The results revealed a high prevalence of micronutrient deficiencies, with 90% of patients exhibiting deficiencies in three or more micronutrients. Notably, every patient presented at least one micronutrient deficiency. Common deficiencies were found in vitamins C (75%), D (65%), H (61%), and K (45%), as well as folic acid (37%), iron (31%), zinc (36%) and selenium (35%). In binary regression analysis, the amount of previous weight loss was significantly associated with a higher prevalence of multiple (>2) micronutrient deficiencies (P = 0.045). Other variables such age (P = 0.449), gender (P = 0.252), BMI (P = 0.265) and MNA-SF score (P = 0.200) did not show any significant association with the prevalence multiple micronutrient deficiencies.

CONCLUSION

The high prevalence of micronutrient deficiencies in malnourished older hospitalized patients underscore the urgent need for targeted interventions to address micronutrient deficiencies in this population, promoting their health status.

The effect of diet-induced weight loss on circulating homocysteine levels in people with obesity and type 2 diabetes

BACKGROUND/AIMS

Having type 2 diabetes (T2D) in combination with being overweight results in an additional increase in cardiovascular disease (CVD) risk. In addition, T2D and obesity are associated with increased levels of total homocysteine (tHcy), possibly contributing to the CVD risk. Weight loss dieting has positive effects on several CVD risk factors, but whether it affects tHcy remains unclear. Therefore, the aim of this study was to determine the effect of a calorie restricted diet on tHcy in overweight people with T2D.

METHODS

In this post-hoc analysis of the POWER study, adults with T2D and a BMI greater than 27 kg/m² were included from the outpatient diabetes clinic of the Erasmus Medical Center, Rotterdam. The patients were subjected to a very low-calorie diet with fortified meal replacements for 20 weeks. Before and after this intervention, blood samples were collected to measure tHcy and other CVD risk factors like glycaemic and lipid parameters.

RESULTS

161 overweight participants with T2D were included, with a mean age of 54 years (range 26-74), mean weight of 104.6 ± 19.9 kg and mean HbA1c of 62.7 ± 14.3 mmol/mol. At baseline, men displayed higher tHcy than women, and tHcy level was positively correlated with body weight and triglyceride levels, while it was negatively correlated with renal function and HDL cholesterol. During the intervention, bodyweight was reduced by a mean of 9.7% (from 104.6 ± 19.9 to 94.5 ± 18.1 kg p < 0.001), and all measured glycaemic and lipid blood parameters improved significantly. However, tHcy remained unchanged (from 12.1 ± 4.1 to 12.1 ± 4.2 umol/L, p = 0.880). The change in tHcy during the intervention was negatively associated with the change in weight and BMI (p = 0.01 and p = 0.008, respectively). People who lost < 10 kg (n = 92) had a mean tHcy change of -0.47 umol/L, while people who lost more than ≥ 10 kg (n = 69) had a mean tHcy change of 0.60 umol/L (p = 0.021).

CONCLUSION

In conclusion, our data show that a calorie restricted diet does not affect tHcy in people with T2D and obesity, despite the use of meal replacements fortified with folic acid and vitamin B12. Our data showed a negative correlation between change in tHcy levels and weight loss, suggesting that people who lost more weight (> 10 kg) showed an increase in tHcy. Future studies should explore the potential increase in tHcy induced by weight loss dieting and target the question if tHcy reduction strategies during weight loss could be clinically beneficial.

MTHFR and risk of stroke and heart disease in a low-folate population: a prospective study of 156 000 Chinese adults

BACKGROUND

The relevance of folic acid for stroke prevention in low-folate populations such as in China is uncertain. Genetic studies of the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism, which increases plasma homocysteine (tHcy) levels, could clarify the causal relevance of elevated tHcy levels for stroke, ischaemic heart disease (IHD) and other diseases in populations without folic acid fortification.

METHODS

In the prospective China Kadoorie Biobank, 156 253 participants were genotyped for MTHFR and 12 240 developed a stroke during the 12-year follow-up. Logistic regression was used to estimate region-specific odds ratios (ORs) for total stroke and stroke types, IHD and other diseases comparing TT genotype for MTHFR C677T (two thymine alleles at position 677 of MTHFR C677T polymorphism) vs CC (two cytosine alleles) after adjustment for age and sex, and these were combined using inverse-variance weighting.

RESULTS

Overall, 21% of participants had TT genotypes, but this varied from 5% to 41% across the 10 study regions. Individuals with TT genotypes had 13% (adjusted OR 1.13, 95% CI 1.09-1.17) higher risks of any stroke [with a 2-fold stronger association with intracerebral haemorrhage (1.24, 1.17-1.32) than for ischaemic stroke (1.11, 1.07-1.15)] than the reference CC genotype. In contrast, MTHFR C677T was unrelated to risk of IHD or any other non-vascular diseases, including cancer, diabetes and chronic obstructive lung disease.

CONCLUSIONS

In Chinese adults, the MTHFR C677T polymorphism was associated with higher risks of stroke. The findings warrant corroboration by further trials of folic acid and implementation of mandatory folic acid fortification programmes for stroke prevention in low-folate populations.

Label-free detection of vitamin B by two-step enhanced Raman technique using dynamic borohydride-reduced silver nanoparticles

A creatively designed novel two-step enhancement technique is presented in which B vitamin molecules are dynamically adsorbed onto the surface of silver nanoparticles by sodium borohydride, followed by local plasmon resonance in the presence of cations (calcium ions), ultimately achieving synergistic chemical and physical enhancement on the same molecule and constructing a "surface hot spots" two-step enhancement platform for vitamin detection. The Raman signal of the promoted vitamin molecule is enhanced by nine orders of magnitude. In a subsequent study it was observed that the vitamin B2 molecules were in a near-vertical image on the surface of the silver nanoparticles, which may also contribute to the Raman signal enhancement. Combined with deep learning techniques, the method has been successfully applied to the detection of B vitamins in body fluids. As an accurate, rapid, reproducible, non-invasive, and versatile assay platform, it holds great promise for the intelligent identification of trace B molecules in food, pharmaceuticals, and the human body.

Intakes of folate, vitamin B6, and vitamin B12 and cardiovascular disease risk: a national population-based cross-sectional study

Background

Only a few studies that investigated dietary intakes of folate, vitamin B6, and vitamin B12 in relation to cariovascular disease (CVD). This study aimed to assess the association of dietary folate, vitamin B6, and vitamin B12 with CVD in the United States population.

Methods

A cross-sectional analysis of 65,322 adults aged ≥ 20 years who participated in the Third National Health and Nutrition Examination Survey (NHANES III) and NHANES 1999-2018. Before 2003, dietary intake data were assessed using a 24-hour dietary call, and two 24-hour dietary calls were used during 2003 and 2018. Odds ratios and 95% confidence intervals (CIs) for CVD associated with dietary folate, vitamin B6, and vitamin B12 were estimated using multivariate logistic regression models.

Results

Dietary vitamin B6 intake were inversely associated with the odds of CVD. In males, the multivariable OR for the highest vs. lowest quartiles of vitamin B6 was 0.77 (95%CI: 0.61-0.97, Ptrend = 0.013) for the odds of CVD. In females, the adjusted OR for the highest quartile of vitamin B6 compared with the lowest quartile was 0.73 (95%CI: 0.56-0.95, Ptrend = 0.038) for the odds of CVD. No significant association was observed between dietary folate and vitamin B12 intakes and the odds of CVD.

Conclusions

Our findings indicate that higher intake of dietary vitamin B6 may be associated with lower prevalence of CVD, suggesting that dietary vitamin B6 has major public health implications in the prevention of CVD in the United States population.

Causal effects of genetically vitamins and sepsis risk: a two-sample Mendelian randomization study

BACKGROUND

In recent years, observational studies have been conducted to investigate the potential impact of vitamins on sepsis. However, many of these studies have produced inconsistent results. Our Mendelian randomization (MR) study aims to evaluate the causality between vitamins and sepsis from a genetic perspective.

METHODS

Our MR study was designed following the STROBE-MR guidelines. Genetic instrumental variables for vitamins including folate, vitamin B12, B6, A (Retinol), C, D, and K were obtained from previous genome-wide association studies (GWAS) and MR studies. Five different sepsis severity levels were included in the analysis. The genetic instrumental variables were screened for potential confounders using PhenoScanner V2. MR analysis was performed using MR-egger, inverse-variance weighted multiplicative random effects (IVW-RE), inverse-variance weighted multiplicative fixed-effects (IVW-FE), and wald ratio methods to assess the relationship between vitamins and sepsis. Sensitivity analysis was performed using the MR-egger_intercept method, and the MR-PRESSO package and Cochran's Q test were used to evaluate the heterogeneity of the instrumental variables.

RESULTS

Our MR study found no statistically significant association between vitamins and sepsis risk, regardless of the type of vitamin (P-value > 0.05). The odds ratios (ORs) for folate, vitamin B6, vitamin B12, vitamin A, vitamin D, vitamin K, and vitamin C were 1.164 (95% CI: 0.895-1.514), 0.987 (95% CI: 0.969-1.005), 0.975 (95% CI: 0.914-1.041), 0.993 (95% CI: 0.797-1.238), 0.861 (95% CI: 0.522-1.42), 0.955 (95% CI: 0.86-1.059), and 1.049 (95% CI: 0.911-1.208), respectively. Similar results were observed in subgroups of different sepsis severity levels.

CONCLUSIONS

Our MR study found no evidence of a causal association between vitamins and sepsis risk from a genetic perspective. Further randomized controlled trials are necessary to confirm these results.

Genetically proxied vitamin B12 and homocysteine in relation to life course adiposity and body composition

OBJECTIVE

Observational studies explore the association between vitamin B12 and obesity. However, causality is not reflected by such observations. We performed a bi-directional Mendelian randomization (MR) study to elucidate the causal relationship of vitamin B12 and homocysteine (Hcy) with life course adiposity and body composition.

METHODS

Two-sample MR analysis was conducted. Independent genetic variants associated with vitamin B12 and Hcy from large-scale genome-wide association studies (GWASs) were utilized as genetic instruments, and their causal effects on five life course adiposity phenotypes (birth weight, body mass index (BMI), childhood BMI, waist circumference, waist-to-hip ratio) and three body compositions (body fat mass, body fat-free mass, body fat percentage) were estimated from UK Biobank, other consortia, and large-scale GWASs. The inverse variance weighting (IVW, main analysis), bi-directional MR, and other six sensitivity MR analyses were performed.

RESULTS

Genetically proxied higher vitamin B12 concentrations were robustly associated with reduced BMI (Beta = -0.01, 95% confidence interval (CI) -0.016 to -0.004, P = 7.60E-04), body fat mass (Beta = -0.012, 95%CI -0.018 to -0.007, P = 1.69E-05), and body fat percentage (Beta = -0.005, 95%CI -0.009 to -0.002, P = 4.12E-03) per SD unit by IVW and other sensitivity analyses. Stratification analysis showed that these results remained significant in females and at different body sites (all P < 0.05 after Bonferroni correction). Bi-directional analyses showed no reverse causation.

CONCLUSIONS

This study provides strong evidence for the causal effect of vitamin B12 on adiposity. This gives novel clues for intervening obesity in public health and nutrition.

Homocysteine Modulates Social Isolation-Induced Depressive-Like Behaviors Through BDNF in Aged Mice

Social isolation is an unpleasant experience associated with an increased risk of mental disorders. Exploring whether these experiences affect behaviors in aged people is particularly important, as the elderly is very likely to suffer from periods of social isolation during their late-life. In this study, we analyzed the depressive-like behaviors, plasma concentrations of homocysteine (Hcy), and brain-derived neurotropic factor (BDNF) levels in aged mice undergoing social isolation. Results showed that depressive-like behavioral performance and decreased BDNF level were correlated with increased Hcy levels that were detected in 2-month isolated mice. Elevated Hcy induced by high methionine diet mimicked the depressive-like behaviors and BDNF downregulation in the same manner as social isolation, while administration of vitamin B complex supplements to reduce Hcy alleviated the depressive-like behaviors and BDNF reduction in socially isolated mice. Altogether, our results indicated that Hcy played a critical role in social isolation-induced depressive-like behaviors and BDNF reduction, suggesting the possibility of Hcy as a potential therapeutic target and vitamin B intake as a potential value in the prevention of stress-induced depression.

Arginine, Transsulfuration, and Folic Acid Pathway Metabolomics in Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis

There is an increasing interest in biomarkers of nitric oxide dysregulation and oxidative stress to guide management and identify new therapeutic targets in patients with chronic obstructive pulmonary disease (COPD). We conducted a systematic review and meta-analysis of the association between circulating metabolites within the arginine (arginine, citrulline, ornithine, asymmetric, ADMA, and symmetric, SDMA dimethylarginine), transsulfuration (methionine, homocysteine, and cysteine) and folic acid (folic acid, vitamin B6, and vitamin B12) metabolic pathways and COPD. We searched electronic databases from inception to 30 June 2023 and assessed the risk of bias and the certainty of evidence. In 21 eligible studies, compared to healthy controls, patients with stable COPD had significantly lower methionine (standardized mean difference, SMD = -0.50, 95% CI -0.95 to -0.05, p = 0.029) and folic acid (SMD = -0.37, 95% CI -0.65 to -0.09, p = 0.009), and higher homocysteine (SMD = 0.78, 95% CI 0.48 to 1.07, p < 0.001) and cysteine concentrations (SMD = 0.34, 95% CI 0.02 to 0.66, p = 0.038). Additionally, COPD was associated with significantly higher ADMA (SMD = 1.27, 95% CI 0.08 to 2.46, p = 0.037), SDMA (SMD = 3.94, 95% CI 0.79 to 7.08, p = 0.014), and ornithine concentrations (SMD = 0.67, 95% CI 0.13 to 1.22, p = 0.015). In subgroup analysis, the SMD of homocysteine was significantly associated with the biological matrix assessed and the forced expiratory volume in the first second to forced vital capacity ratio, but not with age, study location, or analytical method used. Our study suggests that the presence of significant alterations in metabolites within the arginine, transsulfuration, and folic acid pathways can be useful for assessing nitric oxide dysregulation and oxidative stress and identifying novel treatment targets in COPD. (PROSPERO registration number: CRD42023448036.).

High plasma homocysteine level is associated with increased prevalence of the non-remission state in rheumatoid arthritis: Findings from the KURAMA cohort

OBJECTIVES

We aimed to determine the clinical impact of plasma homocysteine levels on disease activity and clinical remission in patients with rheumatoid arthritis (RA).

METHODS

A cross-sectional study was conducted using KURAMA (Kyoto University Rheumatoid Arthritis Management Alliance) database. We enrolled 291 female patients, who were treated in a treat-to-target manner. We measured plasma total homocysteine using a liquid chromatography-tandem mass spectrometry system and collected clinical data including a 28-joint RA disease activity score-erythrocyte sedimentation rate (DAS28-ESR). Clinical remission of disease activity was defined as a DAS28-ESR < 2.6.

RESULTS

In a univariable analysis, the plasma homocysteine concentration was significantly and positively associated with DAS-28-ESR and was higher in the non-remission group than in the remission group. The cutoff value of the plasma homocysteine level was calculated to be 7.9 nmol/mL by the test of the receiver operating characteristic curve analysis. In a multivariable analysis, after adjusting for clinically relevant variables, the high homocysteine level remained a significant positive association for DAS28-ESR (estimate 0.27, P = .0019) and a positive factor for the presence of RA non-remission (odds ratio 2.39, P = .0071).

CONCLUSIONS

Increased plasma homocysteine levels showed a significant positive association with current disease activity and the non-remission state in female patients with RA under treat-to-target treatment. The findings suggest the potential utility of plasma homocysteine as a disease state marker reflecting conditions that are treatment failure and difficult to remission and may provide clinical evidence on the interplay between homocysteine and inflammatory activation in RA.

Effect of vitamin supplementation on polycystic ovary syndrome and key pathways implicated in its development: A Mendelian randomization study

BACKGROUND

Many epidemiologic investigations have explored the relationship between viatmins and polycystic ovary syndrome (PCOS). However, the effectiveness of vitamin, vitamin-like nutrient, or mineral supplementation in reducing the risk of PCOS remains a subject of debate.

AIM

To investigate the impact of plasma levels of vitamins A, B12, D, E, and K on PCOS and key pathways implicated in its development, namely, insulin resistance, hyperlipidemia, and obesity, through Mendelian randomization (MR) analysis.

METHODS

Single nucleotide polymorphisms associated with vitamin levels were selected from genome-wide association studies. The primary analysis was performed using the random-effects inverse-variance-weighted approach. Complementary analyses were conducted using the weighted median, MR-Egger, MR-robust adjusted profile score, and MR-PRESSO approaches.

RESULTS

The results provided suggestive evidence of a decreased risk of PCOS with genetically predicted higher levels of vitamin E (odds ratio [OR] = 0.118; 95% confidence interval [CI]: 0.071-0.226; P < 0.001) and vitamin B12 (OR = 0.753, 95%CI: 0.568-0.998, P = 0.048). An association was observed between vitamin E levels and insulin resistance (OR = 0.977, 95%CI: 0.976-0.978, P < 0.001). Additionally, genetically predicted higher concentrations of vitamins E, D, and A were suggested to be associated with a decreased risk of hyperlipidemia. Increased vitamins K and B12 levels were linked to a lower obesity risk (OR = 0.917, 95%CI: 0.848-0.992, P = 0.031).

CONCLUSION

The findings of this MR study suggest a causal relationship between increased vitamins A, D, E, K, and B12 levels and a reduced risk of PCOS or primary pathways implicated in its development.

Combined use of amlodipine and folic acid are significantly more efficacious than amlodipine alone in lowering plasma homocysteine and blood pressure among hypertensive patients with hyperhomocysteinemia and intolerance to ACEI: A multicenter, randomized, double-blind, parallel-controlled clinical trial

Hyperhomocysteinemia with hypertension can synergistically increase the risk of stroke. The China stroke primary prevention trial showed that combining 0.8 mg folic acid (FA) with angiotensin-converting enzyme inhibitor (ACEI) can effectively lower plasma total homocysteine (tHcy) and blood pressure (BP); and reduce first stroke risk by additional 21% compared to ACEI alone. However, intolerance to ACEI is common in Asians and amlodipine can be alternative. This is a multicenter, randomized, double-blind, parallel-controlled clinical trial (RCT) which evaluated whether amlodipine combined with FA is more efficacious than amlodipine alone in lowering tHcy and BP among Chinese hypertensive with hyperhomocysteinemia and intolerance to ACEI. 351 Eligible patients were randomly assigned by 1:1:1 ratio to receive amlodipine-FA tablet daily (amlodipine 5 mg/FA 0.4 mg, A group); amlodipine 5 mg/FA 0.8 mg tablet daily (B group); amlodipine 5 mg daily (C group, control group). Follow-up was conducted at 2, 4, 6, and 8 weeks. The primary outcome was efficacy of lowering both tHcy and BP at the end of 8-week treatment. Compared with C group, A group had a significantly higher rate of lowering both tHcy and BP (23.3% vs. 6.0%; Odds Ratio [OR], 8.68; 95% CI, 3.04-24.78, P < .001); B group also had a higher rate of lowering both tHcy and BP (20.3% vs. 6.0%; OR: 5.90; 95% CI, 2.11-16.47, P < .001). This RCT showed amlodipine combined with FA compared with amlodipine alone, each had significantly higher efficacy of lowering both tHcy and BP. No difference was found in BP-lowering and occurrence of adverse events between the three groups.

The Associations of Habitual Intake of Sulfur Amino Acids, Proteins and Diet Quality with Plasma Sulfur Amino Acid Concentrations: The Maastricht Study

BACKGROUND

Plasma sulfur amino acids (SAAs), i.e., methionine, total cysteine (tCys), total homocysteine (tHcy), cystathionine, total glutathione (tGSH), and taurine, are potential risk factors for obesity and cardiometabolic disorders. However, except for plasma tHcy, little is known about how dietary intake modifies plasma SAA concentrations.

OBJECTIVE

To investigate whether the intake of SAAs and proteins or diet quality is associated with plasma SAAs.

METHODS

Data from a cross-sectional subset of The Maastricht Study (n = 1145, 50.5% men, 61 interquartile range: [55, 66] y, 22.5% with prediabetes and 34.3% with type 2 diabetes) were investigated. Dietary intake was assessed using a validated food frequency questionnaire. The intake of SAAs (total, methionine, and cysteine) and proteins (total, animal, and plant) was estimated from the Dutch and Danish food composition tables. Diet quality was assessed using the Dutch Healthy Diet Index, the Mediterranean Diet Score, and the Dietary Approaches to Stop Hypertension score. Fasting plasma SAAs were measured by liquid chromatography (LC) tandem mass spectrometry (MS) (LC/MS-MS). Associations were investigated with multiple linear regressions with tertiles of dietary intake measures (main exposures) and z-standardized plasma SAAs (outcomes).

RESULTS

Intake of total SAAs and total proteins was positively associated with plasma tCys and cystathionine. Associations were stronger in women and in those with normal body weight. Higher intake of cysteine and plant proteins was associated with lower plasma tHcy and higher cystathionine. Higher methionine intake was associated with lower plasma tGSH, whereas cysteine intake was positively associated with tGSH. Higher intake of methionine and animal proteins was associated with higher plasma taurine. Better diet quality was consistently related to lower plasma tHcy concentrations, but it was not associated with the other SAAs.

CONCLUSION

Targeted dietary modifications might be effective in modifying plasma concentrations of tCys, tHcy, and cystathionine, which have been associated with obesity and cardiometabolic disorders.

Correlation Analysis and Diagnostic Value of Serum Homocysteine, Cystatin C and Uric Acid Levels with the Severity of Coronary Artery Stenosis in Patients with Coronary Heart Disease

Background

Coronary angiography (CAG) is an invasive examination with high risks and costs and various complications may occur. It is necessary to find a diagnostic method, non-invasiveness, inexpensive with low risk. This study aims to analyze the correlation between the levels of serum homocysteine (Hcy), cystatin C (Cys C) and uric acid (UA) and Gensini score in patients with coronary heart disease (CHD) and assess their diagnostic value for CHD.

Methods

A retrospective analysis was conducted on 1412 patients underwent CAG from October 2019 to December 2021, and we conducted this study from January to July 2022. A total of 765 patients with CHD confirmed by CAG were selected as the research group, while 647 patients revealed as non-obstructive stenosis by CAG as the control group. The serum Hcy, Cys C and UA levels were detected and the correlation between Gensini score and variables was analyzed. The receiver-operating characteristic (ROC) curve was performed to assess the diagnostic value of the Hcy, Cys C and UA for CHD.

Results

The serum Hcy, Cys C and UA levels in the research group were higher as compared with the control group (p<0.05). Spearman correlation and multivariate linear regression analysis showed that there was a significantly positive correlation between Gensini score and serum Hcy, Cys C and UA levels (p<0.05). The ROC curve analysis presented the combined Hcy and Cys C with UA having the highest specificity of diagnostic value for CHD (area under the curve (AUC)=0.768, 95% CI 0.706-0.823, specificity = 72.34%, sensitivity = 67.88%, Youden Index = 0.4022).

Conclusion

The serum Hcy, Cys C and UA levels in patients with CHD were significantly increased, positive correlation with Gensini score. The combined Hcy and Cys C with UA could be used to assess the severity of coronary artery stenosis and provide predictive and early intervention treatment values for CHD and a new way of diagnosing CHD, which is cheap, safe, effective and deserving of clinical application.

Machine learning-based mRNA signature in early acute myocardial infarction patients: the perspective toward immunological, predictive, and personalized

Patients diagnosed with stable coronary artery disease (CAD) are at continued risk of experiencing acute myocardial infarction (AMI). This study aims to unravel the pivotal biomarkers and dynamic immune cell changes, from an immunological, predictive, and personalized viewpoint, by implementing a machine-learning approach and a composite bioinformatics strategy. Peripheral blood mRNA data from different datasets were analyzed, and CIBERSORT was used for deconvoluting human immune cell subtype expression matrices. Weighted gene co-expression network analysis (WGCNA) in single-cell and bulk transcriptome levels was conducted to explore possible biomarkers for AMI, with a particular emphasis on examining monocytes and their involvement in cell-cell communication. Unsupervised cluster analysis was performed to categorize AMI patients into different subtypes, and machine learning methods were employed to construct a comprehensive diagnostic model to predict the occurrence of early AMI. Finally, RT-qPCR on peripheral blood samples collected from patients validated the clinical utility of the machine learning-based mRNA signature and hub biomarkers. The study identified potential biomarkers for early AMI, including CLEC2D, TCN2, and CCR1, and found that monocytes may play a vital role in AMI samples. Differential analysis revealed that CCR1 and TCN2 exhibited elevated expression levels in early AMI compared to stable CAD. Machine learning methods showed that the glmBoost+Enet [alpha=0.9] model achieved high predictive accuracy in the training set, external validation sets, and clinical samples in our hospital. The study provided comprehensive insights into potential biomarkers and immune cell populations involved in the pathogenesis of early AMI. The identified biomarkers and the constructed comprehensive diagnostic model hold great promise for predicting the occurrence of early AMI and can serve as auxiliary diagnostic or predictive biomarkers.

Association of serum water-soluble vitamin exposures with the risk of metabolic syndrome: results from NHANES 2003-2006

Introduction

Existing evidence suggests an association between certain vitamins and metabolic syndrome (MetS), but few epidemiological studies have focused on the effects of multivitamin co-exposure on MetS. This study aims to investigate the associations of the individual or multiple water-soluble vitamins (i.e., vitamin C (VC), vitamin B9 (VB9), and vitamin B12 (VB12)) with co-exposure to MetS, as well as the dose-response relationships among them.

Methods

A cross-sectional study was conducted by employing the National Health and Examination Surveys (NHANESs) 2003-2006. Multivariate-adjusted logistic regression models were used to explore the association between individual serum water-soluble vitamins and the risk of MetS and its components, including waist circumference, triglyceride, high-density lipoprotein, blood pressure, and fasting plasma glucose. Restricted cubic splines were performed to explore the dose-response relationships among them. The quantile g-computation method was adopted to explore the associations of multiple water-soluble vitamins co-exposure with MetS risk and MetS components.

Results

A total of 8983 subjects were involved in the study, of whom 1443 were diagnosed with MetS. The MetS groups had a higher proportion of participants with age ≥60 years, BMI ≥30 kg/m², and insufficient physical activity. Compared with the lowest quartile, the third (OR=0.67, 95% CI: 0.48, 0.94) and highest quartiles (OR=0.52, 95%CI: 0.35, 0.76) of VC were associated with lower MetS risk. Restricted cubic splines showed negative dose-response relationships among VC, VB9 and VB12, and MetS. Regarding MetS components, higher VC quartiles were associated with lower waist circumference, triglyceride, blood pressure, and fasting plasma glucose, while higher VC and VB9 quartiles were associated with higher high-density lipoprotein (HDL). Co-exposure to VC, VB9, and VB12 was significantly inversely associated with MetS, with ORs (95% CI) of 0.81 (0.74, 0.89) and 0.84 (0.78, 0.90) in the conditional and marginal structural models, respectively. Furthermore, we found that VC, VB9, and VB12 co-exposure were negatively associated with waist circumference and blood pressure, while VC, VB9, and VB12 co-exposure were positively associated with HDL.

Conclusion

This study revealed negative associations of VC, VB9, and VB12 with MetS, while the high water-soluble vitamin co-exposure was associated with a lower MetS risk.

Association between body fat composition and hyperhomocysteinemia in the analysis of the baseline data of the Northwest China Natural Population Cohort: Ningxia Project (CNC-NX)

The authors conducted an observational study to explore the association between body fat composition and the risk of hyperhomocysteinemia (HHcy) and their combined effect on the risk of developing cardiovascular disease (CVD). Adults aged 18-74 years from the Northwest China Natural Population Cohort: Ningxia Project (CNC-NX) were recruited in this study. Association between body fat composition and HHcy was evaluated by logistic regression model. Restricted cubic spline was used to find nonlinear association. The impact of the interaction between HHcy and body fat composition on CVD was evaluated using the addition interaction model and mediation effect model. In total, 16 419 participants were included in this research. Body fat percentage, visceral fat level, and abdominal fat thickness were positively associated with overall HHcy (p for trend < .001). Adjusted odds ratios (ORs) in quarter 4 were 1.181 (95% CI: 1.062, 1.313), 1.202 (95% CI: 1.085, 1.332), and 1.168 (95% CI: 1.055, 1.293) for body fat percentage, visceral fat level, and abdominal fat thickness, respectively, compared with those in quarter 1. Subgroup analysis indicated age, estimated glomerular filtration rate (eGFR), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), and CVD were the interaction factors of body fat percentage, visceral fat level, abdominal fat thickness with HHcy (all p for interaction < .05). ORs of CVD were higher in participants with HHcy and high body fat. Body fat composition was positively associated with HHcy, indicating that reducing body, abdominal, and visceral fat content may lower the risk of HHcy and CVD.

Neurological Implications of Vitamin B12 Deficiency in Diet: A Systematic Review and Meta-Analysis

Background: Vitamin B12 is one of the most important B-Vitamins that the human body needs on a daily basis, the lack of which can precipitate several neurological issues. Objectives: This systematic aimed to investigate the neurological implications of Vitamin B12 deficiency and the effects when B12 levels were corrected in susceptible individuals. Methods: The databases PubMed-MEDLINE, Web of Science, Cochrane, and Scopus were all searched using pertinent keywords, reference searches, and citation searches. The terms used to access the database were “Cognition”, “Dietary patterns”, “Neurology”, “Nutritional profile”, and “Vitamin B12”. Results: Vitamin B12 was shown to noticeably improve cognition and other neurological parameters in the short term in older adults and the short-to-medium term in children; however, there was no perceived increase/improvement when the Vitamin was administered in the longer term, either alone or in conjunction with other similar nutritional interventions. Conclusion: Vitamin B12’s role in the improvement of neurological functions over a long-term period remains somewhat inconclusive to date, as the majority of our selected control trials did not display much correlation between the two factors. However, Vitamin B12 did improve cognition levels in both children and older adults over a short course of administration.

Folate, vitamin B6, and vitamin B12 intakes are negatively associated with the prevalence of hypertension: A national population-based study

We hypothesized that the prevalence of hypertension is related to B-vitamin intake in the general population, but it has not been sufficiently studied. This study aimed to investigate the intakes of dietary folate, vitamin B₆, and vitamin B₁₂ concerning hypertension in US adults. A total of 55 569 adults from National Health and Nutrition Examination Survey III and 1999-2014 were included in this study. Nutrient intake was collected from subjects through one or two 24-hour dietary reviews. Multiple logistic regression models were used to examine the relationship between these nutrient intakes and hypertension. Among male participants, dietary folate, vitamin B₆, and vitamin B₁₂ intakes were significantly and negatively associated with the prevalence of hypertension, with multivariate-adjusted odds ratios (ORs) of 0.61 (95% confidence interval [CI], 0.55-0.68), 0.65 (95% CI, 0.59-0.72), and 0.84 (95% CI, 0.75-0.95) for the highest quartile group compared with the lowest group. Results were similar for female participants, with multivariate-adjusted ORs of 0.63 (95% CI, 0.57-0.71), 0.60 (95% CI, 0.53-0.66), and 0.87 (95% CI, 0.77-0.98) for the highest quartile group. Moreover, there was a linear trend (P_trend < .001) in both men and women that the prevalence of hypertension tended to decrease with increased intake of folate, vitamin B₆, and vitamin B₁₂; however, the decreases above the third quartile were negligible. Dietary folate, vitamin B₆, and vitamin B₁₂ were significantly associated negatively with hypertension, indicating that these nutrients might have a protective effect against hypertension in United States adults.

Associations of Serum Folate and Homocysteine Concentrations with All-Cause, Cardiovascular Disease, and Cancer Mortality in Men and Women in Korea: the Cardiovascular Disease Association Study

BACKGROUND

Evidence on the association of serum folate and homocysteine concentrations with risk of mortality in the general population is unclear.

OBJECTIVES

This study aimed to examine the associations of serum folate and homocysteine concentrations with all-cause, CVD, and cancer mortality risk in Korean men and women aged ≥40 y.

METHODS

In this population-based prospective cohort study, serum folate and homocysteine concentrations were measured in a subset of participants enrolled between 2005 and 2012. A total of 21,260 participants were linked to mortality data from the survey date to 31 December 2019. Cox proportional hazards models and restricted cubic splines were used to identify the associations of serum folate and homocysteine concentrations with mortality.

RESULTS

During a median follow-up of 12.3 y, 2501, 549, and 842 deaths were attributed to all-cause, CVD, and cancer, respectively. The prevalence of folate deficiency and hyperhomocysteinemia were higher in men than in women. In men, a nonlinear inverse association was observed between serum folate concentrations and all-cause mortality. Men in the third quartile of serum folate concentrations exhibited a lower risk of all-cause mortality (HR: 0.85; 95% CI: 0.73, 0.99) than those in the lowest quartile. Serum homocysteine concentration was positively associated with all-cause and CVD mortality. Men and women in the highest compared with those in the lowest serum homocysteine quartile showed a higher risk of CVD mortality (HR: 1.60; 95% CI: 1.07, 2.39; and HR: 1.79; 95% CI: 1.11, 2.89, respectively). Hyperhomocysteinemia combined with folate deficiency was associated with increased all-cause, CVD, and cancer-related mortality rates.

CONCLUSIONS

Higher serum homocysteine and lower serum folate concentrations were associated with an increased risk of all-cause, CVD, and cancer-related mortality in Korean adults. The finding of a nonlinear inverse relationship between serum folate concentration and mortality in men warrants further investigation.

Association between homocysteine and nonalcoholic fatty liver disease: Mendelian randomisation study

BACKGROUND

Many observational studies explore the relationship between homocysteine (Hcy) and nonalcoholic fatty liver disease (NAFLD), whereas the causality of this association remains uncertain, especially in European populations. We performed a bidirectional Mendelian randomisation study to elucidate the causal association between Hcy and NAFLD. Furthermore, we explored the relationship of Hcy with liver enzymes, including alkaline phosphatase (ALP), alanine aminotransferase (ALT) and aspartate aminotransferase (AST).

METHODS

Two-sample Mendelian randomisation study was conducted. Summary statistics for Hcy were obtained from a genome-wide association studies (GWAS) meta-analysis comprising 44,147 subjects. Summary-level data for NAFLD were acquired from a GWAS meta-analysis of 8434 cases and 770,180 noncases and another GWAS meta-analysis of 1483 cases and 17,781 noncases. Summary-level data for three liver enzymes were available from the UK Biobank.

RESULTS

Genetic associations of Hcy concentrations with NAFLD and liver enzymes were observed. Genetically predicted higher Hcy concentrations were consistently associated with an increased NAFLD risk in two data sources. The combined odds ratio of NAFLD was 1.25 (95% confidence interval [CI], 1.05-1.45) per SD increase in Hcy concentrations. Genetically predicted higher Hcy concentrations showed significant association with ALP (Beta .69; 95% CI, 0.04-1.34), ALT (Beta 0.56; 95% CI, 0.15-0.97) and AST levels (Beta .57; 95% CI, 0.10-1.04). Genetic liability to NAFLD was not associated with Hcy concentrations.

CONCLUSIONS

This study has clinical implications as it indicates that increased Hcy concentrations increase the relevant liver enzymes and may play a role in NAFLD risk in European populations.

Rap1A accelerates homocysteine-induced ANA-1 cells inflammation via synergy of FoxO1 and DNMT3a

Abnormal elevation of homocysteine (Hcy) level accelerates atherosclerosis through promote macrophage inflammation, while the precise mechanisms remain to be well elucidated. Previous study revealed that Rap1A is involved in the development of atherosclerosis, but little is known regarding the regulation of macrophage inflammation induced by Hcy and its potential mechanisms. In the present study, we demonstrated that Hcy upregulates Rap1A expression and knockdown of Rap1A inhibited pro-inflammatory cytokines IL-6 and TNF-α levels in ANA-1 cells. Mechanistically, DNMT3a-mediated DNA hypomethylation of Rap1A promoter accelerates Hcy-induced ANA-1 cells inflammation. Furthermore, FoxO1 transcriptionally activate Rap1A by direct binding to its promoter. More importantly, Hcy could enhance FoxO1 interaction with DNMT3a and synergistically promote the expression of Rap1A resulting in accelerate ANA-1 cells inflammation. These data indicate that Rap1A is a novel and important regulator in Hcy-induced ANA-1 cells inflammation.

Plasma homocysteine levels and risk of congestive heart failure or cardiomyopathy: A Mendelian randomization study

Background

Although observational studies have demonstrated associations between elevated plasma homocysteine levels and the risk of cardiovascular diseases, controversy remains.

Objective

This study investigated the causal association of plasma homocysteine levels with congestive heart failure and cardiomyopathy risk.

Methods

We performed a two-sample Mendelian randomization (MR) study of congestive heart failure (n = 218,792), cardiomyopathy (n = 159,811), and non-ischemic cardiomyopathy (n = 187,152). Genetic summary data on the association of single-nucleotide polymorphisms with homocysteine were extracted from the most extensive genome-wide association study of 44,147 individuals. MR analyses, including the random-effect inverse variance-weighted (IVW) meta-analysis, weighted median, simple median, maximum likelihood, penalized weighted median, MR-PRESSO, and MR-Egger regression, were used to estimate the associations between the selected single-nucleotide polymorphisms and congestive heart failure or cardiomyopathy.

Results

The MR analyses revealed no causal role of higher genetically predicted plasma homocysteine levels with congestive heart failure risk (random-effect IVW, odds ratio [OR] per standard deviation (SD) increase in homocysteine levels = 1.753, 95% confidence interval [CI] = 0.674-4.562, P = 0.250), cardiomyopathy (random-effect IVW, OR per SD increase in homocysteine levels = 0.805, 95% CI = 0.583 to 1.020, P = 0.189), or non-ischemic cardiomyopathy (random-effect IVW, OR per SD increase in homocysteine levels = 1.064, 95% CI = 0.927-1.222, P = 0.379). The results were consistent with other analytical methods and sensitivity analyses.

Conclusion

Genetically predicted homocysteine level was not associated with congestive heart failure or cardiomyopathy risk. It is unlikely that homocysteine-lowering therapy decreases the incidence or improves the outcomes of congestive heart failure and cardiomyopathy.

Associations of Dietary Zinc-Vitamin B6 Ratio with All-Cause Mortality and Cardiovascular Disease Mortality Based on National Health and Nutrition Examination Survey 1999-2016

Previous studies have suggested a possible association among dietary zinc and vitamin B6 intake and CVD mortality and all-cause mortality. However, evidence on the association of dietary zinc and vitamin B6 intake and their interactions with CVD mortality and all-cause mortality remains unclear. This prospective study utilized data from the US National Health and Nutrition Examination Survey (NHANES) from 1999 to 2016. After a median follow-up of 10.4 years, 4757 deaths were recorded among 36,081 participants. Higher dietary zinc intake levels (≥9.87 mg/day) were associated with lower CVD mortality (hazard ratio (HR) = 0.85, 95% confidence interval (CI): 0.83−0.87). Vitamin B6 intake levels (≥1.73 mg/day) were associated with lower CVD mortality (HR = 0.91, 95% CI: 0.86−0.96) and all-cause mortality (HR = 0.91, 95% CI: 0.90−0.93). Higher dietary zinc intake and higher vitamin B6 intake were associated with a lower risk of CVD mortality, with an interaction between dietary zinc intake levels and vitamin B intake levels (LZLV group (HR, CI): 1.21,1.12−1.29; LZHV group (HR, CI): 1.42, 1.34−1.50; LZHV group (HR, CI): 1.28, 1.14−1.45; HZHV group (HR, CI): ref). There was also a J-type association (p for nonlinear < 0.001) between the dietary zinc−vitamin B6 ratio and CVD mortality, with a high dietary zinc−vitamin B6 ratio increasing the risk of CVD mortality (HR = 1.27, 95% CI: 1.19−1.35), whereas a moderate dietary zinc−vitamin B6 ratio appeared to be beneficial for CVD mortality. These results suggest that increasing the appropriate proportion of dietary zinc and vitamin B6 intake is associated with a lower risk of CVD mortality. Furthermore, precise and representative studies are needed to verify our findings.

Quanduzhong capsules for the treatment of grade 1 hypertension patients with low-to-moderate risk: A multicenter, randomized, double-blind, placebo-controlled clinical trial

Background: Duzhong [DZ (Eucommia ulmoides Oliv.)] is regarded as a traditional Chinese medicine with a history dating back more than 2000 years. This herb is considered a nourishing herb in China and is commonly used as a tonic to strengthen muscles and bones, nourish the kidneys and liver, and soothe miscarriages. Moreover, there is evidence that DZ is capable of regulating blood pressure (BP), and several compounds isolated from DZ have been shown to have a BP-lowering effect. Quanduzhong capsules contain an extract of DZ [Eucommia ulmoides Oliv. (Eucommiaceae; Eucommiae cortex)] that is effective in treating hypertension. This multicenter, randomized, double-blind, placebo-controlled clinical trial sought to evaluate the clinical efficacy of Quanduzhong capsules in the treatment of low-to-moderate risk grade 1 hypertension patients. Materials and methods: A total of 60 patients from 3 centers with documented low-to-moderate risk grade 1 hypertension were randomly assigned in a 1:1 ratio to the test group or the control group. After a 1 week lead-in period using sham Quanduzhong capsules, all patients who met the entry criteria (29 cases in the test group and 29 cases in the control group) entered the 4 week test period. The test group took Quanduzhong capsules, and the control group continued to take sham Quanduzhong capsules. The primary endpoints [24-h mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) determined via 24-h ambulatory blood pressure monitoring (ABPM); office SBP and DBP] and secondary endpoints [mean arterial pressure; mean pulse; daytime mean SBP and DBP; nocturnal mean SBP and DBP; SBP and DBP load; area under the blood pressure (BP) curve; morning peak BP; early morning SBP and DBP; smoothness index of SBP and DBP; 24 h BP mean coefficient of variation (CV); percentage of patients with circadian restoration in ABPM; home BP; quality of life evaluated by WHO Quality of Life-BREF questionnaire; grading and quantitative evaluation of hypertension symptoms; values of plasmatic renin activity, angiotensin II, aldosterone, β-2 microglobulin and homocysteine] were assessed following the treatment. Drug-related adverse events and adverse drug reactions were also compared. Results: After a 4 week test period, a significant difference in the DBP CV between the two groups was observed (-2.49 ± 4.32 vs. 0.76 ± 4.3; p < .05). Moreover, the mean office SBP change was -7.62 ± 9.32 mmHg, and the mean DBP change was -4.66 ± 6.03 (p < .05). Among the three subjects with abnormal homocysteine levels in the test group, homocysteine levels decreased by 6.23 ± 9.15 μmol/L after treatment. No differences were observed between the two groups in any other indicators. After 4 weeks of treatment, there were no significant differences between the groups in terms of safety indicators (p > .05). No abnormal vital signs (except BP) or severe liver or renal function impairment were observed during the treatment periods; in addition, adverse events and drug reactions were mild. Conclusion: Treatment with Quanduzhong capsules reduced office SBP and DBP as well as DBP CV determined by 24-h ambulatory BP monitoring in patients with grade 1 hypertension at low-to-moderate risk. Clinical Trial Registration: https://www.chictr.org.cn/showproj.aspx?proj=32531, identifier ChiCTR1900021699.

Role of Vitamins in Cardiovascular Health: Know Your Facts - Part 1

Cardiovascular (CV) disease (CVD) is a major cause of morbidity and mortality world-wide, thus it is important to adopt preventive interventions. Observational data demonstrating CV benefits of vitamin supplements, advanced by self-proclaimed experts have resulted in ~50% of Americans reporting the use of multivitamins for health promotion; this practice has led to a multi-billion-dollar business of the multivitamin-industry. However, the data on the extensive use of multivitamins show no consistent benefit for CVD prevention or all-cause mortality, while the use of certain vitamins might prove harmful. Thus, the focus of this two-part review is on the attributes or concerns about specific vitamins on CVD. In Part 1, the CV effects of specific vitamins are discussed, indicating the need for further supportive evidence of potential benefits. Vitamin A preserves CV homeostasis as it participates in many biologic functions, including atherosclerosis. However, supplementation could potentially be harmful. Betacarotene, a pro-vitamin A, conveys pro-oxidant actions that may mitigate any other benefits. Folic acid alone and certain B-vitamins (e.g., B1/B2/B6/B12) may reduce CVD, heart failure, and/or stroke, while niacin might increase mortality. Vitamin C has antioxidant and cardioprotective effects. Vitamin D may confer CV protection, but all the data are not in agreement. Combined vitamin E and C have antiatherogenic effects but clinical evidence is inconsistent. Vitamin K seems neutral. Thus, there are individual vitamin actions with favorable CV impact (certain B-vitamins and vitamins C and D), but other vitamins (β-carotene, niacin) may potentially have deleterious effects, which also holds true for high doses of fat-soluble vitamins (A/D/E/K).

Bi-directional causal effect between vitamin B12 and non-alcoholic fatty liver disease: Inferring from large population data

Objectives

Many observational studies evaluate the association between vitamin B12 and non-alcoholic fatty liver disease (NAFLD). However, the causality of this association remains uncertain, especially in European populations. We conducted a bidirectional Mendelian randomization study to explore the association between vitamin B12 and NAFLD.

Methods

Two-sample Mendelian randomization study was conducted. Summary statistics for vitamin B12 were acquired from a genome-wide association studies (GWAS) meta-analysis including 45,576 subjects. Summary-level data for NAFLD was obtained from a GWAS meta-analysis of 8,434 cases and 770,180 non-cases and another GWAS meta-analysis of 1,483 cases and 17,781 non-cases. Summary-level data for 4 enzymes including alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma glutamyltransferase (GGT), was available from the UK Biobank. Inverse variance weighting (as main analysis), weighted median estimate, robust adjusted profile score, MR-Egger, and MR-PRESSO (sensitivity analyses) were performed to calculate causal estimates.

Results

Genetically predicted higher vitamin B12 concentrations were consistently associated with an increased NAFLD in two sources. The combined odds ratio (OR) of NAFLD was 1.30 (95% confidence interval (CI), 1.13 to 1.48; p < 0.001) per SD-increase in vitamin B12 concentrations. Genetic liability to NAFLD was also positively associated with vitamin B12 concentrations (Beta 0.08, 95%CI, 0.01 to 0.16; p = 0.034). Sensitivity analyses also revealed consistent results. Genetically predicted vitamin B12 concentrations showed no significant association with liver enzymes.

Conclusion

The present study indicates that increased serum vitamin B12 concentrations may play a role in NAFLD risk. NAFLD also has a causal impact on elevated vitamin B12 concentrations in the circulation. Notably, vitamin B12 concentrations imply the levels of vitamin B12 in the circulation, and higher intake of vitamin B12 may not directly lead to higher levels of serum vitamin B12, instead the higher levels of vitamin B12 in the circulation may be caused by the dysregulation of the metabolism of this vitamin in this study. There exist bidirectional causal effects between serum vitamin B12 concentrations and risk of NAFLD in European individuals.

Mendelian randomization study to investigate the causal relationship between plasma homocysteine and chronic obstructive pulmonary disease

BACKGROUND

Several observational studies have shown an association between homocysteine (Hcy) levels and chronic obstructive pulmonary disease (COPD), but causal relationships are not clear. Our study aimed to explore the causal relationship between plasma Hcy and COPD by two-sample Mendelian randomization (MR).

METHODS

A two-sample MR study was performed to infer the causal link. Genetically predicted plasma Hcy was selected as an instrumental variable (IV) from published genome-wide association study (GWAS) meta-analyses. COPD with different etiologies was extracted as outcome variables from other GWAS meta-analyses. The main MR analysis was performed using the inverse-variance weighted (IVW) method. Additional analyses were further performed using Cochran's Q-test and MR-Egger regression to evaluate the heterogeneity or horizontal pleiotropy of our findings.

RESULTS

MR analysis showed no significant association between plasma Hcy and COPD. The results of the groups were consistent with the sensitivity analysis and repeated analysis, without heterogeneity or horizontal pleiotropy. The IVW results showed COPD hospital admissions (odds ratio [OR] 1.06, 95% confidence interval [CI] 0.91-1.24, P=0.42), asthma/COPD (OR 0.97, 95% CI 0.89-1.06, P=0.55), COPD-related chronic infection (OR 1.50, 95% CI 0.57-3.99, P=0.41), COPD/asthma/interstitial lung disease (ILD)-related pneumonia or pneumonia-derived septicemia (OR 0.93, 95% CI 0.86-1.02, P=0.13), and COPD-related respiratory insufficiency (OR 1.00, 95% CI 0.7-1.44, P=0.99).

CONCLUSION

There is no direct causal relationship between plasma Hcy and COPD in our study. As Hcy is known to have deleterious effects on endothelial function and vascular homeostasis, further studies are needed to investigate whether additional factors mediate the association between Hcy and COPD.

Effects of four weeks lasting aerobic physical activity on cardiovascular biomarkers, oxidative stress and histomorphometric changes of heart and aorta in rats with experimentally induced hyperhomocysteinemia

The aim of this study was to examine the effects of hyperhomocysteinemia and aerobic physical activity on changes of cardiovascular biomarkers in sera, oxidative stress in cardiac tissue, and histomorphometric parameters of heart and aorta in rats. Experiments were conducted on male Wistar albino rats organized into four groups (n = 10, per group): C (control group): 0.9% NaCl 0.2 mL/day; H (homocysteine group): homocysteine 0.45 µmol/g b.w./day; CPA (control + physical activity group): 0.9% NaCl 0.2 mL/day and a program of physical activity on a treadmill; and HPA (homocysteine + physical activity group) homocysteine 0.45 µmol/g b.w./day and a program of physical activity on a treadmill. Substances were applied subcutaneously twice a day. Lipid peroxidation and relative activity of Mn-superoxide dismutase isoform were significantly higher in active hyperhomocysteinemic rats in comparison to sedentary animals. Atherosclerotic plaques were detected in aorta samples of active hyperhomocysteinemic rats and also, they had increased left ventricle wall and interventricular septum, and transverse diameter of cardiomyocytes compared to sedentary groups. Aerobic physical activity in the condition of hyperhomocysteinemia can lead to increased oxidative stress in cardiac tissue and changes in histomorphometric parameters of the heart and aorta, as well increased lipid parameters and cardiac damage biomarkers in sera of rats.

Causal effects of physical activity on the risk of overall ovarian cancer: A Mendelian randomization study

Objective

Inconsistent results were reported on the association of physical activity with ovarian cancer. However, given the limitations of confounders and inverse causation, the validity of the association remained unclear. Therefore, we conducted a two-sample Mendelian randomization analysis, which can effectively avoid the aforementioned interference, to evaluate whether physical activity had a protective effect on ovarian cancer.

Methods

The exposure of interest was physical activity (both self-reported moderate-to-vigorous physical activity and accelerometer-measured physical activity). Summary statistics for physical activity traits were recruited from the UK Biobank (n  =  91,084-377,234), whereas ovarian cancer summary genetic data were obtained from a genome-wide association study involving 25,509 cases and 40,941 healthy individuals. The inverse variance weighted approach was used as the primary Mendelian randomization method. Sensitivity analyses using Mendelian randomization-Egger regression, weighted median, and Mendelian randomization pleiotropy residual sum and outlier were also performed.

Results

The Mendelian randomization analyses indicated that there was no effect of moderate-to-vigorous physical activity (odds ratio, 1.11; 95% confidence interval: 0.66-1.85; P  =  0.702), accelerometer-measured "average acceleration" (0.99 [0.91-1.08]; P  =  0.848), and "overall activity" physical activity (0.97 [ 0.48-1.95]; P  =  0.927) on the risk of overall ovarian cancer. However, "overall accelerations" physical activity (0.18 [0.05-0.64]; P  =  0.008) were suggestively related to a lower risk of endometrioid ovarian cancer.

Conclusions

The Mendelian randomization analyses suggested that physical activity may not help to decrease the risk of overall ovarian cancer.

HOMOCYSTEINE AND CARDIOVASCULAR DISEASE - A CURRENT REVIEW

Cardiovascular diseases remain the leading cause of death worldwide for the past 20 years. Of these, ischemic heart disease has the highest mortality rate. In over 98% of cases it is caused by atherosclerosis of the coronary arteries. Homocysteine is an amino acid, containing a sulfhydryl group, which is formed as a result of the metabolism of the amino acids methionine and cysteine, which is supplied with protein-containing foods. A small amount of it is necessary for the proper functioning of the body, however, an increased concentration in blood plasma, which hyperhomocysteinemia, negatively affects blood vessels leading to the development of atherosclerosis and thrombotic com¬plications. The adverse effect on blood vessels results from various mechanisms, such as: excessive activation of Toll-like 4 receptor, activation N-methyl-d-aspartate receptors, increased production of reactive oxygen species, and impairment of nitric oxide synthesis. Elevated levels of reactive oxygen species are associated with increased expression of proinflammatory cytokines such as IL-1β, IL-6, TNF-α (tumor necrosis tumor necrosis factor), MCP-1 and intracellular adhesion molecule-1. Another factor contributing to hyperhomocysteinemia is mutation of the MTHFR gene, which in normal conditions is responsible for maintaining homocysteine levels within the normal range. People with MTHFR mutation are more prone to develop atherosclerosis and the following complications: myocardial infarction, stroke, thrombotic episodes and coronary artery disease. The aim of this paper is to present evidence supporting the role of homocysteine in the development of many cardiovascular diseases.

Evaluating the Bidirectional Causal Association Between Daytime Napping and Alzheimer’s Disease Using Mendelian Randomization

Background: Until now, both cross-sectional and longitudinal studies have identified controversial findings about the association between daytime napping and Alzheimer’s disease (AD) or cognitive decline. Therefore, it remains unclear about the causal association between daytime napping and AD or cognitive decline. Objective: We aim to investigate the causal association between daytime napping and AD. Methods: Here, we conduct a bidirectional Mendelian randomization (MR) analysis to investigate the causal association between daytime napping and AD using large-scale GWAS datasets from daytime napping including 452,633 individuals of European ancestry and AD including 35,274 AD and 59,163 controls of European ancestry. A total of five MR methods are selected including inverse-variance weighted (IVW), weighted median, MR-Egger, MR-PRESSO, and contamination mixture method. Results: MR analysis highlights significant causal association of AD with daytime napping using IVW (beta = -0.006, 95% CI [–0.009, –0.002], p = 2.00E-03), but no significant causal association of daytime napping with AD using IVW (OR = 0.76, 95% CI 0.53-1.10, p = 1.40E-01). Conclusion: Our bidirectional MR analysis demonstrates the causal effect of AD on daytime napping. However, there is no causal effect of daytime napping on AD. Our current findings are consistent with recent evidence from other MR studies that highlight little evidence supporting a causal effect of sleep traits on AD and support the causal effect of AD on sleep traits.

Effect of methylenetetrahydrofolate reductase C677T polymorphism on serum folate but not vitamin B12 levels in patients with H-type hypertension

BACKGROUND

Hyperhomocysteinemia (HHcy) is a common complication in Chinese hypertensive patients and associated with methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism, folate, and vitamin B12 (Vit B12) status. This study evaluated the associations of MTHFR C677T polymorphism, folate, and Vit B12 with H-type hypertension.

METHODS AND RESULTS

887 eligible patients with essential hypertension were included. Patients were divided into two groups according to the Hcy level, the H-type hypertension group and the normal hypertension group. Related risk factors such as MTHFR polymorphism, folate and Vit B12 status were analyzed in the two groups. Age, gender, SBP, DBP, MTHFR C677T genotype, folate and Vit B12 differed significantly between H-type hypertension and normal hypertension groups (P < 0.05). MTHFR 677TT variant, gender, folate, and Vit B12 were independent risk factors for the occurrence of H-type hypertension. The risk for TT carriers was 8 times higher than that of CC and CT carriers [OR (95% CI) 8.248 (5.274-12.899)]. Male patients had almost fivefold higher odds than female patients [OR (95% CI) 4.923 (2.741-8.842)]. Folate level of patients with H-type hypertension decreased with the C to T substitution of MTFHR C677T gene (P < 0.05), while Vit B12 level was not associated with the gene (P > 0.05).

CONCLUSIONS

MTHFR 677TT variant, gender, folate, and Vit B12 were risk factors for the occurrence of H-type hypertension. Folate but not Vit B12 was associated with MTFHR C677T polymorphism in patients with H-type hypertension. Accordingly, the above factors may be considered in the prevention and treatment of hypertension.

Circulating Concentrations of Nutrition-Related Factors Are Not Causally Associated With Atrial Fibrillation: A Mendelian Randomization Study

ABSTRACT

Observational studies reported conflicting results regarding the association between circulating concentrations of nutrition-related factors and atrial fibrillation (AF). The aim of this study was to evaluate the potential causal effect of 8 circulating nutrition-related factors (vitamin B12, vitamin E, folate, retinol, β-carotene, iron, zinc, and copper) on AF risk using mendelian randomization (MR). Summary-level data for the nutrition-related factors and AF were obtained from genome-wide association studies conducted among individuals of European ancestry. The genome-wide association study on AF included 60,620 cases and 970,216 controls. A 2-sample MR design was applied for evaluating the causal association. In the primary MR analyses, the inverse variance-weighted method did not identify any causal effect of circulating concentrations of vitamin B12 [β = 0.000, standard error (SE) = 0.021, P = 0.994], vitamin E (β = 0.080, SE = 0.152, P = 0.600), retinol (β = 0.098, SE = 0.397, P = 0.806), folate (β = -0.006, SE = 0.052, P = 0.901), β-carotene (β = 0.014, SE = 0.025, P = 0.560), iron (β = -0.009, SE = 0.072, P = 0.905), zinc (β = 0.038, SE = 0.032, P = 0.239), and copper (β = -0.012, SE = 0.023, P = 0.589) on AF. The MR-Egger and MR pleiotropy residual sum and outlier (MR-PRESSO) analyses did not suggest the presence of pleiotropy. In addition, the lack of association remained in the leave-one-out analysis. This MR study indicates no causal association of circulating concentrations of vitamin B12, vitamin E, folate, retinol, β-carotene, iron, zinc, and copper with AF.

Genome-Wide Studies in Ischaemic Stroke: Are Genetics Only Useful for Finding Genes?

Ischaemic stroke is a complex disease with some degree of heritability. This means that heritability factors, such as genetics, could be risk factors for ischaemic stroke. The era of genome-wide studies has revealed some of these heritable risk factors, although the data generated by these studies may also be useful in other disciplines. Analysis of these data can be used to understand the biological mechanisms associated with stroke risk and stroke outcome, to determine the causality between stroke and other diseases without the need for expensive clinical trials, or to find potential drug targets with higher success rates than other strategies. In this review we will discuss several of the most relevant studies regarding the genetics of ischaemic stroke and the potential use of the data generated.

Plasma Homocysteine Level Is Independently Associated With Conventional Atherogenic Lipid Profile and Remnant Cholesterol in Adults

Background

Homocysteine (Hcy) is an independent risk factor for cardiovascular disease, while mechanisms are unclear. Despite inconsistent and limited, epidemiological and experimental studies indicated that hyperhomocysteinemia (HHcy) affected lipid metabolism. This study aims to investigate the association of plasma Hcy with traditional lipid profiles and remnant cholesterol (RC) in Chinese adults.

Methods

In total, 7,898 subjects aged 20–79 years who underwent a physical examination at Beijing Chao-Yang Hospital in Beijing were included in this study. Fasting plasma total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), apolipoprotein A1 (ApoA1), apolipoprotein B (ApoB), lipoprotein (a) [Lp(a)], Hcy, and other metabolic risk factors were measured by routine automated laboratory methods. RC was calculated as TC minus HDL-C and LDL-C. The linear regression model and logistic regression model were used to assess the relationship between Hcy and lipids after adjusting potential confounders.

Results

Of the subjects, the median level of plasma Hcy was 13.0 μmol/L and 32.3% had HHcy. Plasma Hcy was negatively associated with HDL-C, ApoA1, and Lp(a) and positively associated with TG levels after adjusting age, sex, body mass index, blood pressure, alanine transaminase, aspartate transaminase, creatinine, uric acid, and glucose. HHcy significantly increased the risk of low HDL-C [odds ratio (OR) 1.26; 95%CI (1.11–1.44); p &lt; 0.001]. The net mediation effects of ApoA1 on the relationship between Hcy and HDL-C before and after adjusting confounders were 46.9 and 30.6%, respectively. More interestingly, the RC level was significantly elevated in subjects with HHcy after adjusting other influencing factors (p = 0.025). Hcy presented a positive correlation with RC levels after adjusting the above confounding factors (β = 0.073, p = 0.004), and the correlation was still significant even after controlling other lipids, including TG, LDL-C, HDL-C, ApoA1, ApoB, and Lp(a).

Conclusion

Our study showed that plasma Hcy was not only significantly associated with conventional atherogenic lipids but also independently correlated with RC levels beyond other lipids after controlling potential confounders. This finding proposes that identifying Hcy-related dyslipidemia risk, both traditional lipids and RC residual risk, is clinically relevant as we usher in a new era of targeting Hcy-lowering therapies to fight against dyslipidemia or even cardiovascular disease.

Effect of statin treatment on homocysteine concentrations: an updated systematic review and meta-analysis with meta-regression

BACKGROUND AND AIMS

Statins might exert atheroprotective effects through lowering the pro-atherogenic amino acid homocysteine. We conducted an updated systematic review and meta-analysis of the effect of statins on circulating homocysteine.

METHODS

A systematic literature search was conducted in PubMed, Web of Science, and Scopus, from inception to July 2021. The risk of bias was assessed using the Joanna Briggs Institute Critical Appraisal Checklist for analytical studies. Certainty of evidence was assessed using GRADE.

RESULTS

In 61 treatment arms in 2,218 patients (mean age 55 years, 52% males), statins significantly reduced homocysteine concentrations (weighted mean difference, WMD = -2.46 µmol/L, 95% CI -3.17 to -1.75 µmol/L, p < 0.001; high certainty of evidence). Similar results were observed in a subgroup of 10 randomized placebo-controlled studies (WMD = -2.45 µmol/L, 95% CI -4.43 to -0.47 µmol/L, p = 0.015). The extreme heterogeneity observed was virtually removed in a subgroup of 10 studies using fluorescence polarization immunoassay for homocysteine measurement. There was no publication bias. In sensitivity analysis, the pooled WMD values were not modified when individual studies were sequentially removed. In meta-regression, the WMD was significantly associated with proportion of males and publication year.

CONCLUSIONS

Statins significantly lower homocysteine concentrations.

Causal effects of homocysteine levels on the components of sarcopenia: A two-sample mendelian randomization study

Background: Currently, it is unclear whether there is a causal association between genetically predicted plasma homocysteine (Hcy) levels and the risk of sarcopenia. We performed a Mendelian randomization (MR) study to assess the association between circulating Hcy levels and the components [grip strength, walking pace, and appendicular lean mass (ALM)] of sarcopenia. Methods: Independent single nucleotide polymorphisms (SNPs) significantly associated with plasma Hcy levels served as instrumental variables. Summary-level data regarding the components of sarcopenia. Were obtained from the UK Biobank. Inverse variance weighted (IVW) as the primary method was used for Mendelian randomization (MR) analysis. We also use four models, weighted median, MR-Egger regression, Maximum likelihood, and Penalised weighted median, as supplementary methods to IVW. The MR-Egger intercept test, Cochran's Q test, and "leave-one-out" sensitivity analysis were performed to evaluate the horizontal pleiotropy, heterogeneities, and stability of the causal association between Hcy levels and the components of sarcopenia. Results: The IVW-MR analysis suggested significant negative associations of increased plasma Hcy levels with grip strength (right: effect = -0.036, SE = 0.032, p = 5.53E-4; left: effect = -0.045, SE = 0.010, p = 1.45E-5), walking pace (effect = -0.038, SE = 0.011, p = 3.18E-4), and ALM (effect = -0.058, 0.013, p = 1.03E-5). However, there were no significant associations of decreased plasma Hcy levels with grip strength (right: effect = 0.005, SE = 0.021, p = 0.82; left: effect = -0.006, SE = 0.014, p = 0.64), walking pace (effect = 0.01, 0.020, p = 0.61), or ALM (effect = -0.034, SE = 0.018, p = 0.06).The accuracy and robustness of these findings were confirmed by sensitivity tests. Conclusion: Increased circulating Hcy levels were associated with lower grip strength, slower walking pace, and decreased ALM.

Cardiometabolic, Lifestyle, and Nutritional Factors in Relation to Varicose Veins: A Mendelian Randomization Study

Background We conducted a 2-sample Mendelian randomization study to assess the associations of cardiometabolic, lifestyle, and nutritional factors with varicose veins. Methods and Results Independent single-nucleotide polymorphisms associated with height (positive control), body mass index, type 2 diabetes, diastolic and systolic blood pressure, smoking, alcohol and coffee consumption, 7 circulating vitamins (A, B6, B9, B12, C, 25-hydroxyvitamin D, and E), and 5 circulating minerals (calcium, iron, magnesium, selenium, and zinc) at the genome-wide significance level were used as instrumental variables. Summary-level data for the genetic associations with varicose veins were obtained from the UK Biobank (8763 cases and 352 431 noncases) and the FinnGen consortium (13 928 cases and 153 951 noncases). Genetically predicted higher height, body mass index, smoking, and circulating iron levels were associated with an increased risk of varicose veins. The odds ratios (ORs) per 1-SD increase in the exposure were 1.34 (95% CI, 1.25-1.43) for height, 1.39 (95% CI, 1.27-1.52) for body mass index, 1.12 (95% CI, 1.04-1.22) for the prevalence of smoking initiation, and 1.24 (95% CI, 1.16-1.33) for iron. Higher genetically predicted systolic blood pressure and circulating calcium and zinc levels were associated with a reduced risk of varicose veins, whereas the association for systolic blood pressure did not persist after adjustment for genetically predicted height. The OR was 0.75 (95% CI, 0.62-0.92) per 1-SD increase in calcium levels and 0.97 (95% CI, 0.95-0.98) for zinc. Conclusions This study identified several modifiable risk factors for varicose veins.

Evaluating the Causal Association Between Educational Attainment and Asthma Using a Mendelian Randomization Design

Asthma is a common chronic respiratory disease. In the past 10 years, genome-wide association study (GWAS) has been widely used to identify the common asthma genetic variants. Importantly, these publicly available asthma GWAS datasets provide important data support to investigate the causal association of kinds of risk factors with asthma by a Mendelian randomization (MR) design. It is known that socioeconomic status is associated with asthma. However, it remains unclear about the causal association between socioeconomic status and asthma. Here, we selected 162 independent educational attainment genetic variants as the potential instruments to evaluate the causal association between educational attainment and asthma using large-scale GWAS datasets of educational attainment (n = 405,072) and asthma (n = 30,810). We conducted a pleiotropy analysis using the MR-Egger intercept test and the MR pleiotropy residual sum and outlier (MR-PRESSO) test. We performed an MR analysis using inverse-variance weighted, weighted median, MR-Egger, and MR-PRESSO. The main analysis method inverse-variance weighted indicated that each 1 standard deviation increase in educational attainment (3.6 years) could reduce 35% asthma risk [odds ratio (OR) = 0.65, 95% confidence interval (CI) 0.51–0.85, P = 0.001]. Importantly, evidence from other MR methods further supported this finding, including weighted median (OR = 0.55, 95% CI 0.38–0.80, P = 0.001), MR-Egger (OR = 0.48, 95% CI 0.16–1.46, P = 0.198), and MR-PRESSO (OR = 0.65, 95% CI 0.51–0.85, P = 0.0015). Meanwhile, we provide evidence to support that educational attainment protects against asthma risk dependently on cognitive performance using multivariable MR analysis. In summary, we highlight the protective role of educational attainment against asthma. Our findings may have public health applications and deserve further investigation.

Mitochondrial Lipid Homeostasis at the Crossroads of Liver and Heart Diseases

The prevalence of NAFLD (non-alcoholic fatty liver disease) is a rapidly increasing problem, affecting a huge population around the globe. However, CVDs (cardiovascular diseases) are the most common cause of mortality in NAFLD patients. Atherogenic dyslipidemia, characterized by plasma hypertriglyceridemia, increased small dense LDL (low-density lipoprotein) particles, and decreased HDL-C (high-density lipoprotein cholesterol) levels, is often observed in NAFLD patients. In this review, we summarize recent genetic evidence, proving the diverse nature of metabolic pathways involved in NAFLD pathogenesis. Analysis of available genetic data suggests that the altered operation of fatty-acid β-oxidation in liver mitochondria is the key process, connecting NAFLD-mediated dyslipidemia and elevated CVD risk. In addition, we discuss several NAFLD-associated genes with documented anti-atherosclerotic or cardioprotective effects, and current pharmaceutical strategies focused on both NAFLD treatment and reduction of CVD risk.