Serum total homocysteine concentrations in the third National Health and Nutrition Examination Survey (1991-1994): population reference ranges and contribution of vitamin status to high serum concentrations

Health Patterns across Adulthood: An Age-Based Investigation of the Nutritional Status, Homocysteine, and CoQ10 of Bank Staff

BACKGROUND

This study aimed to evaluate age-specific variations in the blood levels of micronutrients, homocysteine, and CoQ10, along with physical activity (PA) patterns, among 123 Austrian adult bankers in operational and frontline roles (mean age: 43 years; 50% female).

METHODS

Blood analysis was conducted to assess micronutrients and the serum concentrations of homocysteine and CoQ10. The micronutrient values in whole blood were compared to sex-specific reference ranges and categorized as below, within, or above them. The Global Physical Activity Questionnaire was utilized to assess PA patterns. Participants were classified as young adults (18-34 years), middle-aged adults (35-49 years), and older adults (50-64 years).

RESULTS

Significant age-based differences were found in participants' mean homocysteine levels (p = 0.039) and homocysteine categories (p = 0.034), indicating an increasing prevalence of hyperhomocysteinemia with age. No significant difference between age categories was observed for sex, BMI, diet types, PA levels, sedentary behavior, and CoQ10 (p > 0.05). There was no significant age-based difference in the blood concentrations of most minerals and vitamins (p > 0.05), except for magnesium among females (p = 0.008) and copper among males (p = 0.042).

CONCLUSION

The findings offer initial evidence of the age-related differences in the health status of adult bankers, providing insights for customized approaches to occupational health that support the importance of metabolic health and overall well-being across adulthood.

Impact of Statin or Fibrate Therapy on Homocysteine Concentrations: A Systematic Review and Meta-analysis

INTRODUCTION

Statins and fibrates are two lipid-lowering drugs used in patients with dyslipidemia. This systematic review and meta-analysis were conducted to determine the magnitude of the effect of statin and fibrate therapy on serum homocysteine levels.

METHODS

A search was undertaken of the PubMed, Scopus, Web of Science, Embase, and Google Scholar electronic databases up to 15 July 2022. Primary endpoints focused on plasma homocysteine levels. Data were quantitatively analyzed using fixed or random- effect models, as appropriate. Subgroup analyses were conducted based on the drugs and hydrophilic-lipophilic balance of statins.

RESULTS

After screening 1134 papers, 52 studies with a total of 20651 participants were included in the meta-analysis. The analysis showed a significant decrease in plasma homocysteine levels after statin therapy (WMD: -1.388 μmol/L, 95% CI: [-2.184, -0.592], p = 0.001; I2 = 95%). However, fibrate therapy significantly increased plasma homocysteine levels (WMD: 3.459 μmol/L, 95% CI: [2.849, 4.069], p < 0.001; I2 = 98%). The effect of atorvastatin and simvastatin depended on the dose and duration of treatment (atorvastatin [coefficient: 0.075 [0.0132, 0.137]; p = 0.017, coefficient: 0.103 [0.004, 0.202]; p = 0.040, respectively] and simvastatin [coefficient: -0.047 [-0.063, -0.031]; p < 0.001, coefficient: 0.046 [0.016, 0.078]; p = 0.004]), whereas the effect of fenofibrate persisted over time (coefficient: 0.007 [-0.011, 0.026]; p = 0.442) and was not altered by a change in dosage (coefficient: -0.004 [-0.031, 0.024]; p = 0.798). In addition, the greater homocysteine- lowering effect of statins was associated with higher baseline plasma homocysteine concentrations (coefficient: -0.224 [-0.340, -0.109]; p < 0.001).

CONCLUSION

Fibrates significantly increased homocysteine levels, whereas statins significantly decreased them.

Poor ovarian response in assisted reproductive technology cycles is associated with anti-ovarian antibody and pro-inflammatory immune responses

Anti-ovarian antibody (AOA) could be considered an independent marker for autoimmune ovarian disease and predicting future premature ovarian failure (POF). This study aims to investigate if AOA is associated with poor ovarian response (POR) and pro-inflammatory immune responses in women undergoing assisted reproductive technology (ART) cycles. Two hundred forty-eight women undergoing ART cycles were divided into four groups based on AOA test results and the presence of POR: POR(-)/AOA(-) group (N = 148), POR(+)/AOA(-) group (N = 34), POR (-)/AOA(+) group (N = 44), POR(+)/AOA(+) group (N = 22). The POR patients have a significantly higher prevalence of AOA than non-POR patients (P < 0.05). Peripheral blood CD56 + natural killer (NK) cell level (%), NK cytotoxicity, CD19 +CD5 + B-1 cell level (%), and IFN-γ/IL-10 producing T helper (Th) 1/Th2 cell ratios were significantly higher in POR(+)/AOA(+) group than those of other groups (P < 0.001, P < 0.005, P < 0.01, P < 0.05, respectively). TNF-α/IL-10 producing Th1/Th2 cell ratio of POR(+)/AOA(+) group was significantly higher than those of POR(+)/AOA(-) and POR(-)/AOA(-) groups (P < 0.05, respectively). Homocysteine and vitamin D levels of the POR(+)/AOA(+) group were significantly lower than those of other groups (P < 0.005, respectively). Plasminogen activator inhibiter-1 (PAI-1) level of POR(+)/AOA(+) group was significantly higher than that of POR(-)/AOA(-) group (P < 0.05). In the POR(+)/AOA(+) group, the prevalence of antiphospholipid antibodies was significantly higher than that of the POR(+)/AOA(-) group (P = 0.005). Women with autoimmune POR (POR(+)/AOA(+)) have dysregulated pro-inflammatory immune responses and metabolic factors. The diagnostic and therapeutic approaches for autoimmune POR should be differentiated from those for non-autoimmune POR.

Targeting Homocysteine and Hydrogen Sulfide Balance as Future Therapeutics in Cancer Treatment

A high level of homocysteine (Hcy) is associated with oxidative/ER stress, apoptosis, and impairment of angiogenesis, whereas hydrogen sulfide (H2S) has been found to reverse this condition. Recent studies have shown that cancer cells need to produce a high level of endogenous H2S to maintain cell proliferation, growth, viability, and migration. However, any novel mechanism that targets this balance of Hcy and H2S production has yet to be discovered or exploited. Cells require homocysteine metabolism via the methionine cycle for nucleotide synthesis, methylation, and reductive metabolism, and this pathway supports the high proliferative rate of cancer cells. Although the methionine cycle favors cancer cells for their survival and growth, this metabolism produces a massive amount of toxic Hcy that somehow cancer cells handle very well. Recently, research showed specific pathways important for balancing the antioxidative defense through H2S production in cancer cells. This review discusses the relationship between Hcy metabolism and the antiapoptotic, antioxidative, anti-inflammatory, and angiogenic effects of H2S in different cancer types. It also summarizes the historical understanding of targeting antioxidative defense systems, angiogenesis, and other protective mechanisms of cancer cells and the role of H2S production in the genesis, progression, and metastasis of cancer. This review defines a nexus of diet and precision medicine in targeting the delicate antioxidative system of cancer and explores possible future therapeutics that could exploit the Hcy and H2S balance.

Differential impact of environmental factors on systemic and localized autoimmunity

The influence of environmental factors on the development of autoimmune disease is being broadly investigated to better understand the multifactorial nature of autoimmune pathogenesis and to identify potential areas of intervention. Areas of particular interest include the influence of lifestyle, nutrition, and vitamin deficiencies on autoimmunity and chronic inflammation. In this review, we discuss how particular lifestyles and dietary patterns may contribute to or modulate autoimmunity. We explored this concept through a spectrum of several autoimmune diseases including Multiple Sclerosis (MS), Systemic Lupus Erythematosus (SLE) and Alopecia Areata (AA) affecting the central nervous system, whole body, and the hair follicles, respectively. A clear commonality between the autoimmune conditions of interest here is low Vitamin D, a well-researched hormone in the context of autoimmunity with pleiotropic immunomodulatory and anti-inflammatory effects. While low levels are often correlated with disease activity and progression in MS and AA, the relationship is less clear in SLE. Despite strong associations with autoimmunity, we lack conclusive evidence which elucidates its role in contributing to pathogenesis or simply as a result of chronic inflammation. In a similar vein, other vitamins impacting the development and course of these diseases are explored in this review, and overall diet and lifestyle. Recent work exploring the effects of dietary interventions on MS showed that a balanced diet was linked to improvement in clinical parameters, comorbid conditions, and overall quality of life for patients. In patients with MS, SLE and AA, certain diets and supplements are linked to lower incidence and improved symptoms. Conversely, obesity during adolescence was linked with higher incidence of MS while in SLE it was associated with organ damage. Autoimmunity is thought to emerge from the complex interplay between environmental factors and genetic background. Although the scope of this review focuses on environmental factors, it is imperative to elaborate the interaction between genetic susceptibility and environment due to the multifactorial origin of these disease. Here, we offer a comprehensive review about the influence of recent environmental and lifestyle factors on these autoimmune diseases and potential translation into therapeutic interventions.

Association of low-level blood lead with plasma homocysteine in US children and adolescents

Although research in adults has revealed a positive relationship between blood lead levels (BLLs) and homocysteine (Hcy) levels in adults, few studies have investigated this relationship in children and adolescents. We evaluated the relationship between lowlevel blood lead and Hcy levels in US children and adolescents. A total of 8,313 children and adolescents aged 8-19 participated in this study via the National Health and Nutrition Examination Survey 1999-2006. Multivariable linear regression analyses were performed to examine the association between continuous BLLs and Hcy levels. The dose-dependent relationship between continuous BLLs and Hcy levels was analyzed using smooth curve fitting. The average age of participants was 14.1 ± 3.3 years (50.3% male). The mean values of BLLs and Hcy levels were 1.45 μg/dL and 5.77 μmol/L, respectively. In a multivariable adjusted model, an increase in 1.0 μg/dL of BLLs was associated with an elevation of 0.06 μmol/L in Hcy levels (β = 0.06, 95%CI:0.02-0.10, P = 0.001). A linear relationship between BLLs and Hcy levels was discovered using smooth curve fitting (P non-linearity = 0.464). The relationship between low-level blood lead and Hcy levels was stronger on participants with lower serum folate levels (P for interaction = 0.002). Low BLLs were positively associated with plasma Hcy levels in children and adolescents, which varies depending on the levels of folate, vitamin B, and dietary supplements involved in Hcy metabolism.

Relationship between hyperhomocysteinemia and coexisting obesity with low skeletal muscle mass in asymptomatic adult population

The relationship between hyperhomocysteinemia (HHcy) and obesity with low skeletal muscle mass (LMM) has not been established. We aim to assess the association between HHcy and the coexistence of obesity and LMM in asymptomatic adult population. We conducted a population-based cross-sectional study among asymptomatic individuals who underwent measurements of plasma homocysteine and body composition analysis. HHcy was defined as > 15 umol/L, obesity as body mass index ≥ 25 (kg/m²), and LMM as skeletal muscle index less than 2 SD below the sex-specific mean of young adults. The participants were classified into ‘control’, ‘obesity alone’, ‘LMM alone’, and ‘obesity with LMM’. Among 113,805 participants, the prevalence of HHcy was 8.3% in control, 8.7% in obesity alone, 10.0% in LMM alone, and 13.0% in obesity with LMM (p for trend < 0.001). In a multivariable logistic regression analysis, the associations showed a positive trend for HHcy along the groups from obesity alone, to LMM alone, and to obesity with LMM. HHcy was independently associated with the presence of LMM alone (adjusted odds ratio 1.186 [95% confidence interval 1.117–1.259]) and obesity with LMM (1.424 [1.134–1.788]), respectively. This study demonstrated that HHcys was more strongly associated with coexistence of obesity and LMM than either condition alone in the adult population.

Vitamin B-12 Intake from Dairy but Not Meat Is Associated with Decreased Risk of Low Vitamin B-12 Status and Deficiency in Older Adults from Quebec, Canada

BACKGROUND

Vitamin B-12 deficiency can result in irreversible neurologic damages. It is most prevalent among older adults (∼5%-15%), mainly due to impaired absorption. Vitamin B-12 bioavailability varies between food sources, so their importance in preventing deficiency may also vary.

OBJECTIVES

Using the NuAge Database and Biobank, we examined the associations between vitamin B-12 intake (total and by specific food groups) and low vitamin B-12 status and deficiency in older adults.

METHODS

NuAge-the Quebec Longitudinal Study on Nutrition and Successful Aging-included 1753 adults aged 67-84 y who were followed 4 y. Analytic samples comprised 1230-1463 individuals. Dietary vitamin B-12 intake was assessed annually using three 24-h dietary recalls. Vitamin B-12 status was assessed annually as low serum vitamin B-12 (<221 pmol/L), elevated urinary methylmalonic acid (MMA)/creatinine ratio (>2 μmol/mmol), and a combination of both (deficiency). Vitamin B-12 supplement users were excluded. Multilevel logistic regressions, adjusted for relevant confounders, were used.

RESULTS

Across all study years, 21.8%-32.5% of participants had low serum vitamin B-12, 12.5%-17.0% had elevated urine MMA/creatinine, and 10.1%-12.7% had deficiency. Median (IQR) total vitamin B-12 intake was 3.19 μg/d (2.31-4.37). Main sources were "dairy" and "meat, poultry, and organ meats." The ORs (95% CIs) in the fifth quintile compared with the first of total vitamin B-12 intake were as follows: for low serum vitamin B-12, 0.52 (0.37, 0.75; P-trend < 0.0001); for elevated urine MMA/creatinine, 0.63 (0.37, 1.08; P-trend = 0.091); and for vitamin B-12 deficiency, 0.38 (0.18, 0.79; P-trend = 0.006). Similarly, ORs (95% CIs) in the fourth quartile compared with the first of dairy-derived vitamin B-12 intake were 0.46 (0.32, 0.66; P-trend < 0.0001), 0.51 (0.30, 0.87; P-trend = 0.006), and 0.35 (0.17, 0.73; P-trend = 0.003), respectively. No associations were observed with vitamin B-12 from "meat, poultry, and organ meats."

CONCLUSIONS

Higher dietary vitamin B-12 intake, especially from dairy, was associated with decreased risk of low vitamin B-12 status and deficiency in older adults. Food groups might contribute differently at reducing risk of deficiency in older populations.

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.

Vitamin B12 and Plant-Predominant Diets

Vitamin B12 deficiencies are common in individuals consuming plant-predominant diets, including those who consume diary and/or eggs. Deficiencies can lead to megaloblastic anemia and peripheral neuropathy, among other multi-system manifestations. The prevalence, assessment and prevention of vitamin B12 deficiency in patients following plant-predominant diets will be discussed.

Prevalence of hyperhomocysteinemia (HHcy) and its major determinants among hypertensive patients over 35 years of age

OBJECTIVE

Hyperhomocysteinemia (HHcy) and hypertension are associated with cardiovascular events. However, effects of Hcy-lowing interventions on cardiovascular outcome were conflicting. Serum folate level was proposed to be a possible determinant of efficacy of extra folate supplementation on cardiovascular outcome. The aims of the present study were to describe representative information on the levels of serum homocysteine and folate in hypertensive patients, and to explore the major determinants of HHcy.

METHODS

11,007 participants with hypertension were analyzed in this cross-sectional study. Blood pressure and serum levels of biochemical indicators were measured. Multivariate logistic regression model was used to assess the associated factors of HHcy.

RESULTS

Geometric mean of serum total homocysteine was 14.1 (95% CI: 13.9, 14.4) μmol/L and prevalence of HHcy was 36.1 (95% CI: 34.0, 38.1) % in hypertensive patients. HHcy was strongly associated with factors including male sex, older age, elevated serum creatinine (SCr), lower serum folate and vitamin B12, and uncontrolled blood pressure in hypertensive patients. Elevated SCr attributed to HHcy with the etiologic fraction of 0.29. The change of the odds ratio of HHcy associated with folate was significantly higher in patients with elevated SCr compared with that of patients with normal SCr.

CONCLUSION

The results suggested the protection of female sex and higher levels of folate and vitamin B12 from HHcy and attribution of older age and elevated SCr to HHcy. Restoring renal function deserved attention for hypertensive patients to benefit from Hcy-lowing measures.

Managing folate deficiency implies filling the gap between laboratory and clinical assessment

The characterization of folate status in subjects at risk of deficiency and with altered vitamin homeostasis is crucial to endorse preventive intervention health policies, especially in developed countries. Several physiological changes (i.e. pregnancy), clinical situations and diseases have been associated to increased requirement, impaired intake and absorption of folate. However clinical practice guidelines (CPG) endorse folic acid supplementation generally discarding the use of its determination in serum to assess the risk of deficiency and/or its concentration at baseline. Poor confidence on the diagnostic accuracy of serum folate assays still persists in the current CPGs although recent standardization efforts have greatly improved inter-method variability and precision. In this review we critically appraise the methodological issues concerning laboratory folate determination and the evidence on the potential adverse effects of folic acid exposure. The final aim is to build a sound background to promote serum folate-based cost-effective health care policies by optimizing folic acid supplementation in subjects at risk of deficiency and with altered folate homeostasis. Our first result was to adjust in relation to current serum folate assays the thresholds reported by CPGs as index of folate status, defined on the association with metabolic and hematologic indicators. We identify a statistically significant difference between the estimated thresholds and accordingly show that the assessment of folate status actually changes in relation to the assay employed. The use of the method-dependent thresholds here reported may pragmatically endorse the stewardship of folic acid supplementation in clinical practice and increase the cost-effectiveness of health care policies.

Folic Acid Is Related to Muscle Strength and Vitamin A Is Related to Health-Related Quality of Life: Results of the Korea National Health and Nutrition Examination Survey (KNHANES VII 2016-2018)

This study investigated how folic acid affects muscle strength and the effects of vitamin A on quality of life in adults. Baseline data from the Korea National Health and Nutrition Examination Survey (KNHANES VII 2016–2018) was used to find 6112 adults (ages 19–80) meeting study criteria. The participants were divided into three groups: young adults (ages 19–39), middle-aged (ages 40–64), and elderly (≥65 years). Muscle strength was measured using a digital grip strength dynamometer. The EuroQol five-dimension questionnaire measured quality of life. Associations were assessed using multivariate regression and logistic regression. Vitamins and handgrip strength were divided into low and high groups based on the mean. Although vitamin A and folate levels were related to handgrip strength in all subjects, regression demonstrated a significant association between folate and handgrip strength in the elderly. The odds ratios (OR) of higher handgrip strength were statistically significant for elderly participants with high levels of folate compared to those with low levels (OR: 1.55). Vitamin A was associated with quality of life, especially in the self-care dimension for the elderly. Further longitudinal research is needed to examine the relationship between vitamins and muscle strength, as well as vitamins and quality of life.

A comprehensive study of the genotoxic and anti-genotoxic effects of homocysteine in HUVECs and mouse bone marrow cells

Elevated Homocysteine (Hcy) is associated with increased risk of vascular disease, but whether it induces genotoxicity to vascular endothelial cells remains unknown. Here, we conducted a comprehensive study of the genotoxicity, and unexpected anti-genotoxicity, of Hcy by cytokinesis-blocked micronucleus assay in HUVECs and erythrocyte micronucleus test in mouse bone marrow cells. Our experiments led to several important findings. First, while supraphysiological Hcy (SP-Hcy) exhibited remarkable genotoxicity, physiologically-relevant Hcy (PR-Hcy) reduced the basal genotoxicity. Second, among the metabolites of Hcy, cysteine phenocopied the anti-genotoxicity of PR-Hcy and, methionine, S-adenosylhomocysteine and H₂S phenocopied the genotoxicity of SP-Hcy. Third, the genotoxicity of SP-Hcy was mitigated by vitamin B₆, Fe²⁺ and Cu²⁺, but was exacerbated by N-acetylcysteine. Fourth, under pre-, co- or post-treatment protocol, both SP-Hcy and PR-Hcy attenuated the genotoxicity of cisplatin, mitomycin-C, nocodazole or deoxycholate. Finally, 100 and 250 mg/kg Hcy ameliorated cisplatin-induced genotoxicity in bone marrow cells of CF-1 and Kunming mice. Our results suggest that genotoxicity may be one mechanism through which Hcy confers an increased risk for vascular disease, but more importantly, they challenge the long-standing paradigm that Hcy is always harmful to human health. Our study calls for a more systematic effort in understanding the molecular mechanisms underlying the anti-genotoxicity of Hcy.

Hyperhomocysteinemia is an emerging comorbidity in ischemic stroke

Hyperhomocysteinemia or systemic elevation of the amino acid homocysteine is a common metabolic disorder that is considered to be a risk factor for ischemic stroke. However, it is still unclear whether predisposition to hyperhomocysteinemia could contribute to the severity of stroke outcome. This review highlights the advantages and limitations of the current rodent models of hyperhomocysteinemia, describes the consequence of mild hyperhomocysteinemia on the severity of ischemic brain damage in preclinical studies and summarizes the mechanisms involved in homocysteine induced neurotoxicity. The findings provide the premise for establishing hyperhomocysteinemia as a comorbidity for ischemic stroke and should be taken into consideration while developing potential therapeutic agents for stroke treatment.

Nutritional Status Associated with Molecular Biomarkers, Physiological Indices, and Clinical Severity in Parkinson's Disease Patients

This study is intended to explore the associations between nutritional status and molecular biomarkers and the clinical severity of Parkinson's disease (PD), as well as to examine the differences in related factors between PD patients with normal nutrition and those with at risk for malnutrition. A cross-sectional assessment of 82 consecutive outpatients with PD was conducted using the mini nutritional assessment (MNA), Unified Parkinson's Disease Rating Scale (UPDRS), and the Hoehn and Yahr scale to determine the nutritional status, the clinical severity of PD, and the stage of the disease. Recordings of blood samples collected after 12 h of overnight fasting were also assessed in terms of serum levels of glycated hemoglobin (HbA1c), blood urea nitrogen (BUN), creatinine, cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), hemoglobin (Hgb), folate, and vitamin B12. All participants were divided into normal nutrition and malnutrition risk groups via the MNA scores to compare the above-mentioned parameters. The results showed that the total MNA score was significantly correlated with some parts of the UPDRS scale (e.g., Sections 1 and 2) and the levels of HbAlc in PD patients and those with risk for malnutrition, with significantly lower weight and body mass index (BMI), and with lower levels of Hgb and HDL. Higher levels of cholesterol were observed in the malnutrition risk group as compared with the normal nutrition group. The findings suggest that the clinical severity of PD is associated with nutritional status. Body weight, BMI, and the levels of Hgb, cholesterol, and HDL could be, at least partially, important biological markers to monitor malnutrition and the progression of the disease.

Biochemical and Hematological Correlates of Elevated Homocysteine in National Surveys and a Longitudinal Study of Urban Adults

Elevated blood homocysteine (Hcy) among middle-aged adults can increase age-related disease risk, possibly through other biochemical and hematological markers. We selected markers for hyperhomocysteinemia among middle-aged adults, studied time-dependent Hcy-marker associations and computed highly predictive indices of hyperhomocysteinemia, with cross-sectional and longitudinal validations. We used data from the National Health and Nutrition Examination Survey (NHANES III, phase 2, n_max = 4000), the NHANES 1999–2006 (n_max = 10,151) and pooled NHANES (cross-sectional validation). Longitudinal validation consisted of mixed-effects linear regression models (Hcy predicting markers’ annual rates of change), applied to the Healthy Aging in Neighborhoods of Diversity Across the Life Span (HANDLS, n = 227–244 participants, k = 2.4 repeats/participant, Age_base: 30–65 years) data. Machine learning detected nine independent markers for Hcy > 14 µmol/L (NHANES III, phase 2): older age; lower folate and B-12 status; higher serum levels of creatinine, uric acid, alkaline phosphatase, and cotinine; mean cell hemoglobin and red cell distribution widths (RDW); results replicated in the 1999–2006 NHANES [AUC = 0.60–0.80]. Indices combining binary markers increased elevated Hcy odds by 6.9–7.5-fold. In HANDLS, first-visit Hcy predicted annual increase in creatinine, RDW and alkaline phosphatase, with third-visit index (2013–2018) directly predicting Hcy (2004–2009). We provide evidence of the internal and external validity of indices composed of several biomarkers that are strongly associated with elevated Hcy.

The determinants of maternal homocysteine in pregnancy: findings from the Ottawa and Kingston Birth Cohort

OBJECTIVE

Observational studies have linked elevated homocysteine to vascular conditions. Folate intake has been associated with lower homocysteine concentration, although randomised controlled trials of folic acid supplementation to decrease the incidence of vascular conditions have been inconclusive. We investigated determinants of maternal homocysteine during pregnancy, particularly in a folic acid-fortified population.

DESIGN

Data were from the Ottawa and Kingston Birth Cohort of 8085 participants. We used multivariable regression analyses to identify factors associated with maternal homocysteine, adjusted for gestational age at bloodwork. Continuous factors were modelled using restricted cubic splines. A subgroup analysis examined the modifying effect of MTHFR 677C>T genotype on folate, in determining homocysteine concentration.

SETTING

Participants were recruited in Ottawa and Kingston, Canada, from 2002 to 2009.

PARTICIPANTS

Women were recruited when presenting for prenatal care in the early second trimester.

RESULTS

In 7587 participants, factors significantly associated with higher homocysteine concentration were nulliparous, smoking and chronic hypertension, while factors significantly associated with lower homocysteine concentration were non-Caucasian race, history of a placenta-mediated complication and folic acid supplementation. Maternal age and BMI demonstrated U-shaped associations. Folic acid supplementation of >1 mg/d during pregnancy did not substantially increase folate concentration. In the subgroup analysis, MTHFR 677C>T modified the effect of folate status on homocysteine concentration.

CONCLUSIONS

We identified determinants of maternal homocysteine relevant to the lowering of homocysteine in the post-folic acid fortification era, characterised by folate-replete populations. A focus on periconceptional folic acid supplementation and improving health status may form an effective approach to lower homocysteine.

Homocysteine, the methylenetetrahydrofolate reductase 677C>T polymorphism and hypertension: effect modifiers by lifestyle factors and population subgroups

Evidence linking fasting plasma total homocysteine (tHcy) and methylenetetrahydrofolate reductase (MTHFR) 677C>T genotype with hypertension is inconsistent. Differences in B vitamin status, other lifestyle factors or their consideration in analyses might explain this. We investigated these associations in the absence of mandatory fortification with folic acid and B vitamin supplement use. A cross-sectional study was conducted in 788 adults, aged 18-75 years, randomly selected from three Catalonian town population registers. Fasting plasma folate, cobalamin, tHcy, erythrocyte folate, erythrocyte glutathione reductase activation coefficient (EGRAC, functional riboflavin status indicator; increasing EGRAC indicates worsening riboflavin status), MTHFR 677C>T and solute carrier family 1 (SLC19A1) 80 G>A genotypes were determined. Medical history and lifestyle habits were recorded. Principal tHcy determinants differed between women (age, plasma folate, plasma cobalamin, cigarettes/d) and men (MTHFR 677TT genotype, plasma folate, plasma cobalamin and CT genotype). The MTHFR 677C>T polymorphism-tHcy association (β standardised regression coefficients) was stronger in male smokers (0·52, P < 0·001) compared with non-smokers (0·21, P = 0·001) and weaker in participants aged >50 years (0·19, P = 0·007) compared with ≤50 years (0·31, P < 0·001). Hypertension was more probable in the third tHcy tertile compared with other tertiles (OR 1·9; 95 % CI 1·2, 3·0), and in participants aged ≤50 years, for the MTHFR 677TT genotype compared with the CC genotype (OR 4·1; 95 % CI 1·0, 16·9). EGRAC was associated with increased probability of hypertension in participants aged >50 years (OR 6·2; 95 % CI 1·0, 38·7). In conclusion, moderately elevated tHcy and the MTHFR 677CT genotype were associated with hypertension. The MTHFR 677C>T genotype-hypertension association was confined to adults aged ≤50 years.

Genes and genetics in hyperhomocysteinemia and the "1-carbon metabolism": implications for retinal structure and eye functions

Homocysteine (Hcy), a sulfur-containing nonproteinogenic amino acid, is generated as a metabolic intermediate. Hcy constitutes an important part of the "1-carbon metabolism" during methionine turnover. Elevated levels of Hcy known as hyperhomocysteinemia (HHcy) results from vitamin B deficiency, lack of exercise, smoking, excessive alcohol intake, high-fat and methionine-rich diet, and the underlying genetic defects. These factors directly affect the "1-carbon metabolism (methionine-Hcy-folate)" of a given cell. In fact, the Hcy levels are determined primarily by dietary intake, vitamin status, and the genetic blueprint of the susceptible individual. Although Hcy performs an important role in cellular functions, genetic alterations in any of the key enzymes responsible for the "1-carbon metabolism" could potentially upset the metabolic cycle, thus causing HHcy environment in susceptible people. As such, HHcy relates to several clinical conditions like atherosclerosis, myocardial infarction, stroke, cognitive impairment, dementia, Parkinson's disease, multiple sclerosis, epilepsy, and ocular disorders, among others. This article summarizes the findings from our laboratory and public database regarding genetics of HHcy and its effects on ocular disorders, their respective management during dysregulation of the 1-carbon metabolism.

Efficacy Study of Folic Acid Supplementation on Homocysteine Levels in Adolescent Epileptics Taking Antiepileptic Drugs: A Single Blind Randomized Controlled Clinical Trial

BACKGROUND

Epilepsy is a chronic medical condition that requires long-term therapy with antiepileptic drugs (AEDs). However, long-term employment of AEDs may lead to the onset of hyperhomocysteinemia, which has been found to modulate imperative metabolic mechanisms and induce cardiovascular disorders (CVDs). Therefore, adolescent population that have been diagnosed with epilepsy and utilize AEDs are among the most vulnerable, exhibiting higher risks of developing CVDs.

PURPOSE

The present study was designed to explore the effects of folic acid (FA) supplementation on AED-induced hyperhomocysteinemia and CVD risk factors in adolescent epileptics.

METHODS

The randomized clinical trial included adolescent epileptics (i.e., 10-19 years of age) of either sex, on antiepileptic therapy for > 6 months with high homocysteine levels (i.e., >10.9 µmol/L). At the time of enrolment, their baseline BP, lipid and homocysteine levels were recorded. Participants were randomly assigned to either treatment or placebo groups and received the respective treatments. At the end of the first month, BP, lipid and homocysteine levels were recorded and compared to determine the effect of FA on these parameters.

RESULTS AND CONCLUSION

A significant fall in homocysteine levels was observed with FA supplementation (P < 0.05). However, this fall was significantly high in valproic acid treated epileptic patients. In addition, we observed an improvement in high-density lipoprotein levels, a risk factor for CVDs, but the change was statistically insignificant (P > 0.05). The study results suggest that FA supplementation in epileptic patients receiving AED therapy may minimize AED-induced hyperhomocysteinemia and other CVD risk factors.

Cardiovascular Risk Factors and Their Association with Vitamin D Deficiency in Mexican Women of Reproductive Age

Based on a nationally representative sample of young Mexican women aged 20 to 49 years (n = 3260), we sought to explore whether cardiovascular risk factors and acute myocardial infarction (AMI) were associated with vitamin D deficiency (VDD, defined as 25-OH-D <50 nmol/L). To this end, we obtained sociodemographic, serum and anthropometric data from the 2012 National Health and Nutrition Survey (ENSANUT 2012). Analyses were developed through logistic regression models adjusted for potential confounders. The prevalence of VDD was significantly higher in obese women (42.5%, 95% CI; 37.3–47.9) compared to women with a normal body mass index (29.9%, 95% CI; 23.5–37.1, p = 0.05), in those with high total cholesterol (TC) (45.6% 95% CI; 39.4–51.9) compared to those with normal TC levels (33.9%, 95% CI 30–38.1, p = 0.03), and in those with insulin resistance (IR) (44%, 95% CI; 36.9–51.7) or type 2 diabetes mellitus (T2DM) (58.6%, 95% CI 46.9–69.4) compared to those with normal glycemia (no insulin resistance: 34.7%, 95% CI; 30.9–38.8, p = 0.04 and no T2DM: 34.9%, 95% CI 31.4–38.6, p < 0.001). Utilizing individual models to estimate cardiovascular risk according to VDD, we found that the odds of being obese (odds ratio, OR: 1.53, 95% CI 1.02–2.32, p = 0.05), or having high TC levels (OR: 1.43, 95% CI; 1.05–2.01, p = 0.03), T2DM (OR: 2.64, 95% CI; 1.65–4.03, p < 0.001), or IR (OR: 1.48, 95% CI 1.04–2.10, p = 0.026) were significantly higher in women with VDD (p < 0.05). Odds were not statistically significant for overweight, high blood pressure, sedentarism, AMI, high serum concentration of triglycerides, homocysteine, or C-reactive protein models. In conclusion, our results indicate that young Mexican women with VDD show a higher prevalence of cardiovascular risk factors.

Hyperhomocysteinemia leads to exacerbation of ischemic brain damage: Role of GluN2A NMDA receptors

Hyperhomocysteinemia has been implicated in several neurodegenerative disorders including ischemic stroke. However, the pathological consequences of ischemic insult in individuals predisposed to hyperhomocysteinemia and the associated etiology are unknown. In this study, we evaluated the outcome of transient ischemic stroke in a rodent model of hyperhomocysteinemia, developed by subcutaneous implantation of osmotic pumps containing L-homocysteine into male Wistar rats. Our findings show a 42.3% mortality rate in hyperhomocysteinemic rats as compared to 7.7% in control rats. Magnetic resonance imaging of the brain in the surviving rats shows that mild hyperhomocysteinemia leads to exacerbation of ischemic injury within 24 h, which remains elevated over time. Behavioral studies further demonstrate significant deficit in sensorimotor functions in hyperhomocysteinemic rats compared to control rats. Using pharmacological inhibitors targeting the NMDAR subtypes, the study further demonstrates that inhibition of GluN2A-containing NMDARs significantly reduces ischemic brain damage in hyperhomocysteinemic rats but not in control rats, indicating that hyperhomocysteinemia-mediated exacerbation of ischemic brain injury involves GluN2A-NMDAR signaling. Complementary studies in GluN2A-knockout mice show that in the absence of GluN2A-NMDARs, hyperhomocysteinemia-associated exacerbation of ischemic brain injury is blocked, confirming that GluN2A-NMDAR activation is a critical determinant of the severity of ischemic damage under hyperhomocysteinemic conditions. Furthermore, at the molecular level we observe GluN2A-NMDAR dependent sustained increase in ERK MAPK phosphorylation under hyperhomocysteinemic condition that has been shown to be involved in homocysteine-induced neurotoxicity. Taken together, the findings show that hyperhomocysteinemia triggers a unique signaling pathway that in conjunction with ischemia-induced pathways enhance the pathology of stroke under hyperhomocysteinemic conditions.

Relationship between Homocysteine and Muscle Strength Decline: The Baltimore Longitudinal Study of Aging

Background

Decreased muscle strength is strongly associated with future mobility limitations in older adults. Homocysteine is a risk factor for vascular disease and may exacerbate muscle strength decline. The present study aimed to examine the association between homocysteine levels and muscle strength in adults aged 50 years or older.

Methods

Data were from 1,101 participants of The Baltimore Longitudinal Study of Aging between December 2004 and March 2015. Muscle strength was measured using grip strength. Mixed effects linear regression was used to estimate the association between homocysteine and muscle strength in men and women, separately.

Results

Total mean follow-up time was 4.7 ± 3.1 years, range from 0 to 10.1 years. Baseline mean grip strength was 39.9 kg for men and 25.5 kg for women. Grip strength declined over the follow-up time for both men and women. Among women, there was a significant inverse relationship between homocysteine and grip strength, where grip strength declined as a function of increasing homocysteine over time (β = -0.05, p = .031). Among men, an increase of 1 μmol/L in homocysteine was associated with -0.10 kg decrease in grip strength, though not significantly.

Conclusions

In this study of healthy older adults aged 50 years or older, higher homocysteine was related to lower muscle strength in women. This is the first study to characterize the relationship over a long follow-up period. Future research should focus on assessing homocysteine as a marker of physical function decline and translating the relationship into clinical and public health practice.

Folate and vitamin B12 status and their relation to hematological indices in healthy adults of Iranians: Azar cohort study

BACKGROUND:

Folate and vitamin B₁₂ are essential micronutrients, the deficiency of which can be associated with public health problems worldwide.

AIM:

The aims of this study were to assess the folate and vitamin B₁₂ status of healthy adults and the effect of gender differences on their deficiency using serum folate, vitamin B₁₂ and red blood cell (RBC) folate as biomarkers and their relation to hematological indices.

METHODS:

This study was a part of the Azar cohort study, which is designed as a noncommunicable disease survey in the population of Shabestar, East Azerbaijan, Iran. A total of 95 healthy adults (35 men, 60 women) were chosen according to exclusion criteria and assessed using demographic characteristics and blood sampling.

RESULTS:

Low concentrations of serum folate, vitamin B₁₂ and RBC folate were detected in 16.8%, 61.1% and 40% of all subjects, respectively. Prevalence of low serum folate and vitamin B₁₂ was higher in men than women (25.7% versus 11.7% for serum folate, 77.1% versus 51.7% for serum vitamin B₁₂).A significant positive correlation was found between hemoglobin and serum folate, vitamin B₁₂ and RBC folate concentrations ( r = 0.279, 0.335, 0.228, respectively). No statistically significant correlation between mean corpuscular volume and serum folate, vitamin B₁₂ and RBC folate was seen ( r = -0.049, -0.030, -0.016, respectively).

CONCLUSIONS:

There was a high prevalence of low folate and vitamin B₁₂ concentrations in our community. Regarding the impact of these two vitamins deficiency on overall health, we suggest further investigations with more participants. In addition, monitoring hematological indices could be useful in people with folate and vitamin B₁₂ deficiency.

Approaches to improving micronutrient status assessment at the population level

Optimising micronutrient status globally is a major health priority. Nutritional biomarkers are critical for the identification of nutrient inadequacies in light of the limitations of dietary assessment methods. Early diagnosis and prevention of nutrient inadequacies require sensitive, validated and harmonised methods to determine and monitor micronutrient status in individual healthcare and population-based surveys. Important criteria in the identification, validation and implementation of nutritional biomarkers include the testing of biomarker specificity and sensitivity, and their response to dietary as well as physiologic changes, e.g. age or pregnancy. Nutritional status can be categorised into deficient, suboptimal, adequate and excess status, where appropriate, and provided cut-offs are available. Cut-offs are quantitative measures to reflect health outcomes and are important in validating nutritional surveys, interventions and monitoring of populations. For many biomarkers, available cut-offs have limited interpretability and are most commonly derived in adult populations only. For the comparison of studies from across the globe, the harmonisation of analytical methods is essential and can be realised with the use of internationally available reference material and interlaboratory comparison studies. This narrative review describes current efforts on identifying and validating existing and new biomarkers, the derivation of biomarker cut-offs, and international efforts on harmonisation of laboratory methods for biomarker quantitation and their interpretation, in the example of B-vitamins. Establishing sensitive, reliable and cost-efficient biomarkers and related cut-offs for use in populations across the globe are critical to facilitating the early diagnosis of micronutrient inadequacies on the clinical and community-based level for timely intervention and disease prevention.

Restoration of skeletal muscle homeostasis by hydrogen sulfide during hyperhomocysteinemia-mediated oxidative/ER stress condition 1

Elevated homocysteine (Hcy), i.e., hyperhomocysteinemia (HHcy), causes skeletal muscle myopathy. Among many cellular and metabolic alterations caused by HHcy, oxidative and endoplasmic reticulum (ER) stress are considered the major ones; however, the precise molecular mechanism(s) in this process is unclear. Nevertheless, there is no treatment option available to treat HHcy-mediated muscle injury. Hydrogen sulfide (H₂S) is increasingly recognized as a potent anti-oxidant, anti-apoptotic/necrotic/pyroptotic, and anti-inflammatory compound and also has been shown to improve angiogenesis during ischemic injury. Patients with CBS mutation produce less H₂S, making them vulnerable to Hcy-mediated cellular damage. Many studies have reported bidirectional regulation of ER stress in apoptosis through JNK activation and concomitant attenuation of cell proliferation and protein synthesis via PI3K/AKT axis. Whether H₂S mitigates these detrimental effects of HHcy on muscle remains unexplored. In this review, we discuss molecular mechanisms of HHcy-mediated oxidative/ER stress responses, apoptosis, angiogenesis, and atrophic changes in skeletal muscle and how H₂S can restore skeletal muscle homeostasis during HHcy condition. This review also highlights the molecular mechanisms on how H₂S could be developed as a clinically relevant therapeutic option for chronic conditions that are aggravated by HHcy.

Dietary intake and nutritional status in patients with systemic lupus erythematosus

INTRODUCTION

Systemic lupus erythematosus (SLE) is a chronic inflammatory autoimmune disease. Despite the influence of diet on inflammation, dietary habits in patients with systemic lupus erythematosus (SLE) are not well established. The study objective was to assess dietary intake and nutritional status in SLE patients.

PATIENTS AND METHODS

A cross-sectional study was conducted in 92 patients with SLE. Nutritional status was determined by body mass index (BMI) and energy/nutrient distribution of diet was analyzed and compared to a control group. Dietary reference intakes (DRIs) issued by the Spanish Societies of Nutrition, Feeding and Dietetics (FESNAD) and the Spanish Society of Community Nutrition (SENC) were used as reference.

RESULTS

Body mass index was normal in 53.26% of patients, while 43.48% had excess weight. Energy, protein, and fat intake was significantly lower in the SLE group (p=0.003, p=0.000, and p=0.001 respectively). Protein and fat contribution to total energy was higher, while that of carbohydrate and fiber was lower than recommended. Most patients did not reach the recommended intake for iron (88%), calcium (65.2%), iodine (92.4%), potassium (73.9%), magnesium (65%), folate (72.8%), and vitamins E (87%) and D (82.6%), but exceeded the recommendations for sodium and phosphorus.

CONCLUSIONS

Spanish SLE patients have an unbalanced diet characterized by low carbohydrate/fiber and high protein/fat intakes. Significant deficiencies were seen in micronutrient intake. Dietary counseling to improve nutrition would therefore be advisable in management of SLE.

Association between insulin resistance and total plasma homocysteine levels in type 2 diabetes mellitus patients in south west Nigeria

AIM

To determine the levels of serum homocysteine and its association with insulin resistance among T2DM patients at Obafemi Awolowo University Teaching Hospital, Ile Ife Nigeria.

METHODS

It was a cross sectional study. It involved consecutive recruitment of 100 T2DM subjects with 100 age and sex matched controls. The fasting plasma glucose, serum creatinine, fasting lipid profile, glycosylated haemoglobin levels, fasting serum insulin and plasma homocysteine concentration were done. Insulin resistance was also determined. SPSS version 17.0 was used for data analysis.

RESULTS

The mean age of subjects was not significantly different from controls. (58.9±8.3 vs. 59.0±8.3years, p=0.926 respectively). Mean Homocysteine level (tHcy) was significantly higher among T2DM subjects compared to controls (27.4±12.1 and 8.3±3.2μmol/L respectively, p=0.0001). Hyperhomocystinaemia was commoner among diabetic subjects compared with controls (81% vs. 5%, p<0.0001). T2DM with hyperhomocystinaemia were more likely to have poorer glucose control profile using glycated haemoglobin (7.4±1.9 vs 6.4±1.4%, p=0.04) and fasting blood glucose 8.6±2.2 vs 7.5±2.4mmol/L p=0.047 and insulin resistance (4.4±4.3 vs. 2.0±0.6, p=0.02) compared with T2DM with normohomocystenaemia. There were significant associations between hyperhomocystinaemic T2DM patients and IR, HbA1c, TC, TG and LDL cholesterol.

CONCLUSION

The study showed higher homocysteine levels in T2DM than controls. Homocysteine level is worsened by increasing insulin resistance, dyslipidaemia and poor glucose control. Homocysteine level is a potential cardiovascular risk marker in type 2 diabetic mellitus subjects.

Effect of Combination Folic Acid, Vitamin B6 , and Vitamin B12 Supplementation on Fracture Risk in Women: A Randomized, Controlled Trial

Epidemiologic studies have demonstrated an association of elevated plasma homocysteine levels with greater bone resorption and fracture risk. Vitamins B₁₂ , B₆ , and folic acid are cofactors in homocysteine metabolism, and supplementation with B vitamins is effective in lowering homocysteine levels in humans. However, randomized trials of supplemental B vitamins for reduction of fracture risk have been limited. Therefore, we performed an ancillary study to the Women's Antioxidant and Folic Acid Cardiovascular Study (WAFACS), a large randomized trial of women with preexisting cardiovascular disease or three or more coronary risk factors, to test whether a daily B vitamin intervention including folic acid (2.5 mg/day), vitamin B₆ (50 mg/day), and vitamin B₁₂ (1 mg/day) reduces nonspine fracture risk over 7.3 years of treatment and follow-up. Among 4810 women, we confirmed 349 nonspine fracture cases by centralized review of medical records. In a substudy of 300 women (150 in treatment group and 150 controls) with paired plasma samples at randomization and follow-up (7.3 years later), we measured two bone turnover markers, including C-terminal cross-linking telopeptide of type I collagen (CTX) and intact type I procollagen N-propeptide (P1NP). In Cox proportional hazards models based on intention-to-treat, we found no significant effects of B vitamin supplementation on nonspine fracture risk (relative hazard = 1.08; 95% confidence interval, 0.88 to 1.34). In a nested case-cohort analysis, there were no significant effects of B vitamins on fracture risk among women with elevated plasma homocysteine levels, or low levels of vitamins B₁₂ or B₆ , or folate at baseline. Furthermore, treatment with B vitamins had no effect on change in markers of bone turnover. We found no evidence that daily supplementation with B vitamins reduces fracture risk or rates of bone metabolism in middle-aged and older women at high risk of cardiovascular disease. © 2017 American Society for Bone and Mineral Research.

Dietary B Vitamins and Depression in Persons with Human Immunodeficiency Virus Infection: The Positive Living with HIV (POLH) Study

B vitamins have beneficial roles in mental health functional impairments; however, research on the role of B vitamins in depression among HIV-infected persons is limited. This study assessed the association between dietary B vitamin intake and depressive symptoms in a cohort of HIV-infected persons. A cross-sectional survey was conducted among 314 HIV-infected persons (180 men and 134 women) aged 18 to 60 y residing in the Kathmandu, Nepal. The Beck Depression Inventory-I was used to measure depression, with a cutoff score of 20 or higher. Dietary intake was assessed using two nonconsecutive 24-h dietary recalls. The relationships between B vitamins and depressive symptoms were assessed using multiple logistic regression analysis. Twenty-six percent participants (men: 23%; women: 29%) were depressed. More than two thirds of participants' B vitamins intake were below the estimated average requirements (EAR) level. Low intake of riboflavin was associated with an increased risk of depression in women but not in men. Multivariate OR (95% CI) for depression in the first, second, and third tertiles of riboflavin in total participants were 1 (reference), 0.87 (0.46-1.64), and 0.49 (0.24-0.98), respectively (p for trend=0.048) and in women were 1 (reference), 0.94 (0.36-2.40), and 0.23 (0.07-0.77), respectively (p for trend=0.020). No clear associations were seen between other B vitamins and depressive symptoms in either sex. Low intake of riboflavin was independently associated with an increased risk of depressive symptoms in all participants and in HIV-infected women. Further prospective studies are warranted to confirm the role of vitamin B vitamins in depressive symptoms among HIV-infected persons.

Homocysteine, Alcoholism, and Its Potential Epigenetic Mechanism

Alcohol is the most socially accepted addictive drug. Alcohol consumption is associated with some health problems such as neurological, cognitive, behavioral deficits, cancer, heart, and liver disease. Mechanisms of alcohol-induced toxicity are presently not yet clear. One of the mechanisms underlying alcohol toxicity has to do with its interaction with amino acid homocysteine (Hcy), which has been linked with brain neurotoxicity. Elevated Hcy impairs with various physiological mechanisms in the body, especially metabolic pathways. Hcy metabolism is predominantly controlled by epigenetic regulation such as DNA methylation, histone modifications, and acetylation. An alteration in these processes leads to epigenetic modification. Therefore, in this review, we summarize the role of Hcy metabolism abnormalities in alcohol-induced toxicity with epigenetic adaptation and their influences on cerebrovascular pathology.

Vitamin B12 among Vegetarians: Status, Assessment and Supplementation

Cobalamin is an essential molecule for humans. It acts as a cofactor in one-carbon transfers through methylation and molecular rearrangement. These functions take place in fatty acid, amino acid and nucleic acid metabolic pathways. The deficiency of vitamin B12 is clinically manifested in the blood and nervous system where the cobalamin plays a key role in cell replication and in fatty acid metabolism. Hypovitaminosis arises from inadequate absorption, from genetic defects that alter transport through the body, or from inadequate intake as a result of diet. With the growing adoption of vegetarian eating styles in Western countries, there is growing focus on whether diets that exclude animal foods are adequate. Since food availability in these countries is not a problem, and therefore plant foods are sufficiently adequate, the most delicate issue remains the contribution of cobalamin, which is poorly represented in plants. In this review, we will discuss the status of vitamin B12 among vegetarians, the diagnostic markers for the detection of cobalamin deficiency and appropriate sources for sufficient intake, through the description of the features and functions of vitamin B12 and its absorption mechanism.

Effects of Ready-to-Eat-Cereals on Key Nutritional and Health Outcomes: A Systematic Review

BACKGROUND

In many countries breakfast cereals are an important component of breakfast. This systematic review assesses the contribution of consumption of ready-to eat cereal (RTEC) to the recommended nutrient intake. Furthermore, the effects of RTEC consumption on key health parameters are investigated as well as health promoting properties of RTEC.

METHOD

The Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE and CINAHL have been searched up till 16th of June 2015. Randomized controlled trials were excluded if RTEC were used during hypocaloric diets, if RTEC were eaten at other times than breakfast and if breakfasts included other products than RTEC, milk and fruit. Observational studies were excluded when "breakfast cereals" were not defined or their definition included cooked cereals. From cross-sectional studies only data concerning energy and nutrient intake as well as micronutrient status were used.

RESULTS

From 4727 identified citations 64 publications met the inclusion criteria of which 32 were cross-sectional studies, eight prospective studies and 24 randomized controlled trials. Consumption of RTEC is associated with a healthier dietary pattern, concerning intake of carbohydrates, dietary fiber, fat and micronutrients, however total sugar intake is higher. Persons consuming RTEC frequently (≥ 5 times/week) have a lower risk of inadequate micronutrient intake especially for vitamin A, calcium, folate, vitamin B 6, magnesium and zinc. Evidence from prospective studies suggests that whole grain RTEC may have beneficial effects on hypertension and type 2 diabetes. Consumption of RTEC with soluble fiber helps to reduce LDL cholesterol in hypercholesterolemic men and RTEC fortified with folate can reduce plasma homocysteine.

DISCUSSION

One of the review's strengths is its thorough ex/inclusion of studies. Limitations are that results of observational studies were based on self-reported data and that many studies were funded by food-industry.

CONCLUSION

Consumption of RTEC, especially of fiber-rich or whole grain RTEC, is implicated with several beneficial nutritional and health outcomes. The effect on body weight, intestinal health and cognitive function needs further evaluation. Of concern is the higher total sugar intake associated with frequent RTEC consumption.

Dietary B Vitamins and Serum C-Reactive Protein in Persons With Human Immunodeficiency Virus Infection: The Positive Living With HIV (POLH) Study

BACKGROUND

B vitamins may have beneficial roles in reducing inflammation; however, research on the role of B vitamins in inflammation among HIV-infected persons is lacking.

OBJECTIVE

This study assessed the association between B vitamins and serum C-reactive protein (CRP) concentrations in HIV-infected persons.

METHODS

A cross-sectional survey was conducted among 314 HIV-infected persons (180 men and 134 women) aged 18 to 60 years residing in the Kathmandu, Nepal. High-sensitive and regular serum CRP concentrations were measured by the latex agglutination nephelometry and latex agglutination turbidimetric method, respectively. Dietary intake was assessed using 2 nonconsecutive 24-hour dietary recalls. The relationships between B vitamins and serum CRP concentrations were assessed using multiple regression analysis.

RESULTS

The multivariate-adjusted geometric mean of serum CRP concentrations was significantly decreased with an increasing B vitamins intake across quartiles of niacin (P for trend = .007), pyridoxine (P for trend = .042), and cobalamin (P for trend = .037) in men. In men, the mean serum CRP concentrations in the highest quartiles of niacin, pyridoxine, and cobalamin were 63%, 38%, and 58%, respectively, lower than that in the lowest quartile. In women, the mean serum CRP concentrations in the highest quartiles of riboflavin (P for trend = .084) and pyridoxine (P for trend = .093) were 37% and 47%, respectively, lower than that in the lowest quartile.

CONCLUSION

High intake of niacin, pyridoxine, or cobalamin was independently associated with decreased serum CRP concentrations among HIV-infected men. Further prospective studies are warranted to confirm the role of B vitamins in inflammation among HIV-infected persons.

Dietary guanidinoacetic acid increases brain creatine levels in healthy men

OBJECTIVE

Guanidinoacetic acid (GAA) is an experimental dietary additive that might act as a creatine source in tissues with high-energy requirements. In this case study, we evaluated brain levels of creatine in white matter, gray matter, cerebellum, and thalamus during 8 wk oral GAA administration in five healthy men and monitored the prevalence and severity of side effects of the intervention.

METHODS

Volunteers were supplemented daily with 36 mg/kg body weight (BW) of GAA for the first 4 wk of the intervention; afterward GAA dosage was titrated ≤60 mg/kg BW of GAA daily. At baseline, 4, and 8 wk, the participants underwent brain magnetic resonance spectroscopy, clinical chemistry studies, and open-ended questionnaire for side-effect prevalence and severity.

RESULTS

Brain creatine levels increased in similar fashion in cerebellum, and white and gray matter after GAA supplementation, with an initial increase of 10.7% reported after 4 wk, and additional upsurge (7.7%) from the weeks 4 to 8 follow-up (P < 0.05). Thalamus creatine levels decreased after 4 wk for 6.5% (P = 0.02), and increased nonsignificantly after 8 wk for 8% (P = 0.09). GAA induced an increase in N-acetylaspartate levels at 8-wk follow-up in all brain areas evaluated (P < 0.05). No participants reported any neurologic adverse event (e.g., seizures, tingling, convulsions) during the intervention.

CONCLUSIONS

Supplemental GAA led to a region-dependent increase of the creatine pool in the human brain. This might be relevant for restoring cellular bioenergetics in disorders characterized by low brain creatine and functional enzymatic machinery for creatine synthesis, including neurodegenerative diseases, brain tumors, or cerebrovascular disease.

Micronutrients and Risk of Parkinson's Disease: A Systematic Review

Parkinson’s disease (PD) is the second most common neurodegenerative disorder. Although the precise pathogenetic mechanisms of PD remain undetermined, there appears to be both genetic and environmental factors that contribute to the risk of developing PD. With regard to environmental risk factors, there has been significant interest related to the role of diet, nutrition, and nutrients on the onset and progression of PD. As the current treatments are predominantly focused on symptomatic management, efforts must be directed toward prevention of the PD and identification of potentially modifiable risk and preventive factors. This comprehensive review gives an overview of studies examining the role of micronutrients in PD, and provides guidance on the value of the reported outcomes.

Chronic Neck Pain and Cervico-Craniofacial Pain Patients Express Similar Levels of Neck Pain-Related Disability, Pain Catastrophizing, and Cervical Range of Motion

Background. Neck pain (NP) is strongly associated with cervico-craniofacial pain (CCFP). The primary aim of the present study was to compare the neck pain-related disability, pain catastrophizing, and cervical and mandibular ROM between patients with chronic mechanical NP and patients with CCFP, as well as asymptomatic subjects. Methods. A total of 64 participants formed three groups. All participants underwent a clinical examination evaluating the cervical range of motion and maximum mouth opening, neck disability index (NDI), and psychological factor of Pain Catastrophizing Scale (PCS). Results. There were no statistically significant differences between patients with NP and CCFP for NDI and PCS (P > 0.05). One- way ANOVA revealed significant differences for all ROM measurements. The post hoc analysis showed no statistically significant differences in cervical extension and rotation between the two patient groups (P > 0.05). The Pearson correlation analysis shows a moderate positive association between NDI and the PCS for the group of patients with NP and CCFP. Conclusion. The CCFP and NP patient groups have similar neck disability levels and limitation in cervical ROM in extension and rotation. Both groups had positively correlated the NDI with the PCS.

Decreased Brain Levels of Vitamin B12 in Aging, Autism and Schizophrenia

Many studies indicate a crucial role for the vitamin B₁₂ and folate-dependent enzyme methionine synthase (MS) in brain development and function, but vitamin B₁₂ status in the brain across the lifespan has not been previously investigated. Vitamin B₁₂ (cobalamin, Cbl) exists in multiple forms, including methylcobalamin (MeCbl) and adenosylcobalamin (AdoCbl), serving as cofactors for MS and methylmalonylCoA mutase, respectively. We measured levels of five Cbl species in postmortem human frontal cortex of 43 control subjects, from 19 weeks of fetal development through 80 years of age, and 12 autistic and 9 schizophrenic subjects. Total Cbl was significantly lower in older control subjects (> 60 yrs of age), primarily reflecting a >10-fold age-dependent decline in the level of MeCbl. Levels of inactive cyanocobalamin (CNCbl) were remarkably higher in fetal brain samples. In both autistic and schizophrenic subjects MeCbl and AdoCbl levels were more than 3-fold lower than age-matched controls. In autistic subjects lower MeCbl was associated with decreased MS activity and elevated levels of its substrate homocysteine (HCY). Low levels of the antioxidant glutathione (GSH) have been linked to both autism and schizophrenia, and both total Cbl and MeCbl levels were decreased in glutamate-cysteine ligase modulatory subunit knockout (GCLM-KO) mice, which exhibit low GSH levels. Thus our findings reveal a previously unrecognized decrease in brain vitamin B₁₂ status across the lifespan that may reflect an adaptation to increasing antioxidant demand, while accelerated deficits due to GSH deficiency may contribute to neurodevelopmental and neuropsychiatric disorders.

A Randomized Controlled Trial to Examine the Effect of 2-Year Vitamin B12 and Folic Acid Supplementation on Physical Performance, Strength, and Falling: Additional Findings from the B-PROOF Study

Elevated homocysteine concentrations are associated with a decline in physical function in elderly persons. Homocysteine-lowering therapy may slow down this decline. This study aimed to examine the effect of a 2-year intervention of vitamin B12 and folic acid supplementation on physical performance, handgrip strength, and risk of falling in elderly subjects in a double-blind, randomized placebo-controlled trial. Participants aged ≥65 years with elevated plasma homocysteine concentrations [12-50 µmol/L (n = 2919)] were randomly assigned to daily supplementation of 500 µg vitamin B12, 400 µg folic acid, and 600 IU vitamin D3, or to placebo with 600 IU vitamin D3. Physical performance (range 0-12) and handgrip strength (kg) were measured at baseline and after 2 years. Falls were reported prospectively on a research calendar. Intention-to-treat (primary) and per-protocol (secondary) analyses were performed. Physical performance level and handgrip strength significantly decreased during the follow-up period, but this decline did not differ between groups. Moreover, time to first fall was not significantly different (HR: 1.0, 95% CI 0.9-1.2). Secondary analyses on a per-protocol base identified an interaction effect with age on physical performance. In addition, the treatment was associated with higher follow-up scores on the walking test (cumulative OR: 1.3, 95% CI 1.1-1.5). Two-year supplementation of vitamin B12 and folic acid was neither effective in reducing the age-related decline in physical performance and handgrip strength, nor in the prevention of falling in elderly persons. Despite the overall null-effect, the results provide indications for a positive effect of the intervention on gait, as well as on physical performance among compliant persons >80 years. These effects should be further tested in future studies.

Is vitamin B12 deficiency a risk factor for cardiovascular disease in vegetarians?

The goal of this paper is to describe the role of vitamin B12 deficiency in cardiovascular disease development among vegetarians. Vegetarians have a high prevalence of vitamin B12 deficiency. Deficiency of this vitamin is associated with a variety of atherogenic processes that are mainly, but not exclusively, due to vitamin B12 deficiency-induced hyperhomocysteinemia. Each 5-μmol/L increase above 10 μmol/L of serum homocysteine is associated with a 20% increased risk of circulatory health problems. Mean homocysteine concentration >10 μmol/L among vegetarians was reported in 32 of 34 reports. Macrocytosis associated with vitamin B12 deficiency is also associated with fatal and non-fatal coronary disease, myocardial infarction, stroke, and other circulatory health problems. Compared with non-vegetarians, vegetarians have an improved profile of the traditional cardiovascular disease risk factors, including serum lipids, blood pressure, serum glucose concentration, and weight status. However, not all studies that assessed cardiovascular disease incidence among vegetarians reported a protective effect. Among studies that did show a lower prevalence of circulatory health problems, the effect was not as pronounced as expected, which may be a result of poor vitamin B12 status due to a vegetarian diet. Vitamin B12 deficiency may negate the cardiovascular disease prevention benefits of vegetarian diets. In order to further reduce the risk of cardiovascular disease, vegetarians should be advised to use vitamin B12 supplements.

Efficacy of Supplementation with B Vitamins for Stroke Prevention: A Network Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Supplementation with B vitamins for stroke prevention has been evaluated over the years, but which combination of B vitamins is optimal for stroke prevention is unclear. We performed a network meta-analysis to assess the impact of different combinations of B vitamins on risk of stroke.

METHODS

A total of 17 trials (86 393 patients) comparing 7 treatment strategies and placebo were included. A network meta-analysis combined all available direct and indirect treatment comparisons to evaluate the efficacy of B vitamin supplementation for all interventions.

RESULTS

B vitamin supplementation was associated with reduced risk of stroke and cerebral hemorrhage. The risk of stroke was lower with folic acid plus vitamin B6 as compared with folic acid plus vitamin B12 and was lower with folic acid plus vitamin B6 plus vitamin B12 as compared with placebo or folic acid plus vitamin B12. The treatments ranked in order of efficacy for stroke, from higher to lower, were folic acid plus vitamin B6 > folic acid > folic acid plus vitamin B6 plus vitamin B12 > vitamin B6 plus vitamin B12 > niacin > vitamin B6 > placebo > folic acid plus vitamin B12.

CONCLUSIONS

B vitamin supplementation was associated with reduced risk of stroke; different B vitamins and their combined treatments had different efficacy on stroke prevention. Folic acid plus vitamin B6 might be the optimal therapy for stroke prevention. Folic acid and vitamin B6 were both valuable for stroke prevention. The efficacy of vitamin B12 remains to be studied.

Effect of daily vitamin B-12 and folic acid supplementation on fracture incidence in elderly individuals with an elevated plasma homocysteine concentration: B-PROOF, a randomized controlled trial

BACKGROUND

Elevated plasma homocysteine concentrations are a risk factor for osteoporotic fractures. Lowering homocysteine with combined vitamin B-12 and folic acid supplementation may reduce fracture risk.

OBJECTIVE

This study [B-vitamins for the PRevention Of Osteoporotic Fractures (B-PROOF)] aimed to determine whether vitamin B-12 and folic acid supplementation reduces osteoporotic fracture incidence in hyperhomocysteinemic elderly individuals.

DESIGN

This was a double-blind, randomized, placebo-controlled trial in 2919 participants aged ≥65 y with elevated homocysteine concentrations (12-50 μmol/L). Participants were assigned to receive daily 500 μg vitamin B-12 plus 400 μg folic acid or placebo supplementation for 2 y. Both intervention and placebo tablets also contained 600 IU vitamin D3. The primary endpoint was time to first osteoporotic fracture. Exploratory prespecified subgroup analyses were performed in men and women and in individuals younger than and older than age 80 y. Data were analyzed according to intention-to-treat and per-protocol principles.

RESULTS

Osteoporotic fractures occurred in 61 persons (4.2%) in the intervention group and 75 persons (5.1%) in the placebo group. Osteoporotic fracture risk was not significantly different between groups in the intention-to-treat analyses (HR: 0.84; 95% CI: 0.58, 1.21) or per-protocol analyses (HR: 0.81; 95% CI: 0.54, 1.21). For persons aged >80 y, in per-protocol analyses, osteoporotic fracture risk was lower in the intervention group than in the placebo group (HR: 0.27; 95% CI: 0.10, 0.74). The total number of adverse events (including mortality) did not differ between groups. However, 63 and 42 participants in the intervention and placebo groups, respectively, reported incident cancer (HR: 1.56; 95% CI: 1.04, 2.31).

CONCLUSIONS

These data show that combined vitamin B-12 and folic acid supplementation had no effect on osteoporotic fracture incidence in this elderly population. Exploratory subgroup analyses suggest a beneficial effect on osteoporotic fracture prevention in compliant persons aged >80 y. However, treatment was also associated with increased incidence of cancer, although the study was not designed for assessing cancer outcomes. Therefore, vitamin B-12 plus folic acid supplementation cannot be recommended at present for fracture prevention in elderly people. The B-PROOF study was registered with the Netherlands Trial Register (trialregister.nl) as NTR1333 and at clinicaltrials.gov as NCT00696414.

Spinal cord infarction in carriers of methylenetetrahydrofolate reductase-polymorphism-like unique risk factor: report of two cases

STUDY DESIGN

A case report.

OBJECTIVE

To present two cases of spinal cord infarction (SCI) in carriers of the C677T methylenetetrahydrofolate reductase (MTHFR) polymorphism.

SETTING

Physical Medicine and Rehabilitation Department, Section for Rehabilitation and Traumatology, Hospital Virgen de las Nieves, Granada, Spain.

METHODS

Two cases are presented, one with SCI at the C7 level American Spinal Injury Association (ASIA) A and one at the C5 level (ASIA A). One patient presented an acute onset of tetraplegia and the other a centromedular syndrome. In both cases the patients were carriers of the MTHFR polymorphism, which is a unique risk factor.

RESULTS

Increased blood levels of homocysteine related to mutation of the MTHFR gene increase the risk of a thrombotic episode, triggering the development of SCI. These two cases increase the limited number reported in the recent literature regarding MTHFR polymorphism carriers suffering from thrombotic SCI.

CONCLUSION

MTHFR mutation can be considered a risk factor for thrombotic SCI, but it is not the sole risk factor. We propose that a consensus regarding the inclusion of anticoagulation treatment after confirmation of the diagnosis in these patients is needed.

Relationship of homocysteine and homocysteine-related vitamins to bone mineral density in Japanese patients with type 2 diabetes

Aims/Introduction:  To estimate nutritional risk factors for osteoporosis in patients with type 2 diabetes, bone mineral density, homocysteine level, and intakes and levels of Hcy‐related vitamins including folate, vitamin B₆ and vitamin B₁₂ were analyzed in a cross‐sectional study.

Materials and Methods:  Lumbar spine and femoral neck bone mineral density, serum concentrations of vitamin B₆, vitamin B₁₂, and folate and plasma homocysteine levels were measured in 125 Japanese patients with type 2 diabetes. Nutrient intake values were evaluated using a food frequency questionnaire.

Results:  Homocysteine was inversely correlated with bone mineral density, and with both dietary intake and serum concentration of folate. Intake of green vegetables was correlated with intake and level of folate and homocysteine levels. When the population was analyzed across the quartiles, bone mineral density, serum folate concentration, folate intake and intake of green vegetables were lowest in the highest homocysteine group.

Conclusions:  In patients with type 2 diabetes, the nutritional status of folate might affect the homocysteine level, a putative risk factor for osteoporosis. (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2010.00088.x, 2011)

Guidelines for the prevention of stroke in patients with stroke and transient ischemic attack: a guideline for healthcare professionals from the American Heart Association/American Stroke Association

The aim of this updated guideline is to provide comprehensive and timely evidence-based recommendations on the prevention of future stroke among survivors of ischemic stroke or transient ischemic attack. The guideline is addressed to all clinicians who manage secondary prevention for these patients. Evidence-based recommendations are provided for control of risk factors, intervention for vascular obstruction, antithrombotic therapy for cardioembolism, and antiplatelet therapy for noncardioembolic stroke. Recommendations are also provided for the prevention of recurrent stroke in a variety of specific circumstances, including aortic arch atherosclerosis, arterial dissection, patent foramen ovale, hyperhomocysteinemia, hypercoagulable states, antiphospholipid antibody syndrome, sickle cell disease, cerebral venous sinus thrombosis, and pregnancy. Special sections address use of antithrombotic and anticoagulation therapy after an intracranial hemorrhage and implementation of guidelines.

Low calcium intake is associated with high plasma homocysteine levels in postmenopausal women

Nutritional interventions targeting homocysteine remain controversial, and further nutritional research is warranted. We thus sought to explore the determinants of plasma homocysteine other than B-group vitamins. This cross-sectional study surveyed the nutritional status of 713 Japanese postmenopausal women using a semiquantitative food frequency questionnaire. Associations between total energy, protein, fat, carbohydrate, and vitamin A and K intakes and homocysteine were insignificant. Mean homocysteine in the second (536.1 ± 34.7 mg/day) and third (712.9 ± 115.6 mg/day) tertiles of calcium intake were lower than in the first tertile (379.6 ± 76.6 mg/day) by -0.57 nmol/mL (95 % confidence interval, -1.10 to-0.04, p = 0.04) and -1.18 nmol/mL (-1.76 to -0.60, p<0.01), respectively, after adjustment for lifestyle and clinical factors (trend p\0.01). Mean homocysteine in those with dietary calcium intake above the median (>536 mg/day) were lower regardless of the folic acid concentration; the differences were -1.59 nmol/mL (-2.33 to -0.85, p = 0.02) and -0.75 nmol/mL (-1.37 to-0.12, p<0.01) for the high (<7.8 ng/mL) and low folic acid groups, respectively. There was no significant association between calcium and folic acid (p = 0.08). In conclusion, further prospective research to confirm our findings is needed for the development of nutritional inventions targeting homocysteine.