Exercise-Induced Hyperhomocysteinemia Is Not Related to Oxidative Damage or Impaired Vascular Function in Amateur Middle-Aged Runners under Controlled Nutritional Intake

To determine the influence of different doses of maximal acute exercise on the kinetics of plasma homocysteine (tHcy) and its relationship with oxidative status and vascular function, nine recreational runners completed a 10 km race (10K) and a marathon (M). Blood samples were collected before (Basal), immediately post-exercise (Post0), and after 24 h (Post24). Nutritional intake was controlled at each sample point. A significant increase in tHcy was observed after both races, higher after M. Basal levels were recovered at Post24 after 10K, but remained elevated at Post 24 for M. A significant decrease in GSH/GSSG ratio was observed in Post0, especially marked after M. Furthermore, this increase in pro-oxidant status remained at Post24 only after M. Other oxidative status markers failed to confirm this exercise-induced pro-oxidant status except glutathione peroxidase activity that was lower in Post24 compared to Basal in 10K and in Post0 and Post24 in M. No statistical correlation was found between oxidative markers and tHcy. No significant changes were observed in the concentration of endothelial cell adhesion molecules (VCAM-1 and E-Selectin) and VEGF. In conclusion, tHcy increases in an exercise–dose–response fashion but is not related to endothelial dysfunction mediated by oxidative stress mechanisms.

A holistic approach to healthy ageing: how can people live longer, healthier lives?

BACKGROUND

Although lifespan is increasing, there is no evidence to suggest that older people are experiencing better health in their later years than previous generations. Nutrition, at all stages of life, plays an important role in determining health and wellbeing.

METHODS

A roundtable meeting of UK experts on nutrition and ageing considered key aspects of the diet-ageing relationship and developed a consensus position on the main priorities for research and public health actions that are required to help people live healthier lives as they age.

RESULTS

The group consensus highlighted the requirement for a life course approach, recognising the multifactorial nature of the impact of ageing. Environmental and lifestyle influences at any life stage are modified by genetic factors and early development. The response to the environment at each stage of life can determine the impact of lifestyle later on. There are no key factors that act in isolation to determine patterns of ageing and it is a combination of environmental and social factors that drives healthy or unhealthy ageing. Too little is known about how contemporary dietary patterns and sedentary lifestyles will impact upon healthy ageing in future generations and this is a priority for future research.

CONCLUSIONS

There is good evidence to support change to lifestyle (i.e. diet, nutrition and physical) activity in relation to maintaining or improving body composition, cognitive health and emotional intelligence, immune function and vascular health. Lifestyle change at any stage of life may extend healthy lifespan, although the impact of early changes appears to be greatest.

Muscular contraction frequency does not affect plasma homocysteine concentration in response to energy expenditure- and intensity-matched acute exercise in sedentary males

Acute exercise seems to increase total plasma homocysteine (tHcy); since this variable associated with cardiovascular risk, it is important to understand the determinants of its response to all types of exercise. The aim of this study was to examine the impact of cycling at 2 different rates of muscle contraction on the complete tHcy kinetics. Eight young sedentary males were required to complete 2 isocaloric (400 kcal) acute exercise trials at 50% peak oxygen uptake on separate occasions at 50 or 80 rpm. Blood samples were drawn at different points before (4 h before exercise and immediately before exercise), during (10, 20, 30, 45, and 60 min during exercise), and after exercise (immediately and 19 h after exercise). Dietary and lifestyle factors were controlled during the research. Maximum tHcy occurred during exercise for both conditions (50 rpm: 11.4 ± 2.7 μmol·L^-1; 80 rpm: 10.8 ± 3.2 μmol·L^-1). From this point onwards tHcy declined until the cessation of exercise and continued descending below pre-exercise values at 19 h postexercise (p < 0.05). No hyperhomocysteinemia were observed at any sampling point in both trials. In conclusion, the different muscular contraction frequency during exercise has no impact on tHcy during an acute bout of exercise in sedentary individuals, when at least 400 kcal are spent during exercise and the nutritional status for folate, B₁₂, and B₆ is adequate. This information is relevant to further inform healthy exercise prescription, not only in terms of duration and intensity of exercise, but also taking into account frequency of contraction.

Stress cardiomyopathy: Is it limited to Takotsubo syndrome? Problems of definition

In 2006, Takotsubo syndrome (TTC) was described as a distinct type of stress-induced cardiomyopathy (stress cardiomyopathy). However, when thinking about Takotsubo cardiomyopathy from the viewpoints of the AHA and ESC classifications, 2 possible problems may arise. The first potential problem is that a forecast of disease outcome is lacking in the ESC classification, whereas the AHA only states that 'outcome is favorable with appropriate medical therapy'. However, based on the literature data, one can make a general conclusion that occurrence of myocardial lesions in TTC (i.e., myocardial fibrosis and contraction-band necrosis) causes the same effects as in other diseases with similar levels of myocardial damage and should not be considered to have a lesser impact on mortality. To summarise, TTC can cause not only severe complications such as pulmonary oedema, cardiogenic shock, and dangerous ventricular arrhythmias, but also damage to the myocardium, which can result in the development of potentially fatal conditions even after the disappearance of LV apical ballooning. The second potential problem arises from the definition of TTC as a stress cardiomyopathy in the AHA classification. In fact, the main factors leading to TTC are stress and microvascular anginas, since, as has been already discussed, coronary spasm can cause myocardium stunning, resulting in persistent apical ballooning. Thus, based on this review, 3 distinct types of stress cardiomyopathies exist (variant angina, microvascular angina, and TTC), with poor prognosis. Adding these diseases to the classification of cardiomyopathies will facilitate diagnosis and preventive prolonged treatment, which should include intensive anti-stress therapy.

Positive Association of Plasma Homocysteine Levels with Cardio-Ankle Vascular Index in a Prospective Study of Japanese Men from the General Population

AIM

Observational studies have reported that elevated homocysteine (Hcy) levels are associated with the risk of cardiovascular disease (CVD). However, interventions that lower Hcy do not provide a corresponding risk reduction. Therefore, the causal role of Hcy in CVD remains unclear. This 5-year prospective study investigated the associations of Hcy levels, folate intake, and host factors with arterial stiffness among the general Japanese population.

METHODS

We prospectively recruited 658 participants (40-69 years old) from the general population during regular health checkup examinations. Arterial stiffness was evaluated using the cardio-ankle vascular index (CAVI) at baseline and the 5-year follow-up. Folate intake was estimated using a structured questionnaire. Genotyping was used to evaluate the MTHFR C677T and MS A2756G gene polymorphisms. Ultrafast liquid chromatography was used to measure total plasma Hcy levels. Association between these variables and CAVI values was evaluated using general linear regression and logistic regression models that were adjusted for atherosclerosis-related factors.

RESULTS

Men had higher Hcy levels and CAVI values and lower folate intake than women (all, p＜0.001). At baseline, Hcy, folate intake, and the two genotypes were not associated with CAVI values for both sexes. Among men, Hcy levels were positively associated with CAVI values at the 5-year follow-up (p=0.033). Folate intake and the two genotypes were not associated with the 5-year CAVI values.

CONCLUSION

Plasma Hcy may be involved in arterial stiffness progression, as monitored using CAVI, among men.

Altered one-carbon metabolism in posttraumatic stress disorder

BACKGROUND

Posttraumatic stress disorder (PTSD) is associated with increased morbidity and mortality through somatic conditions, particularly cardiovascular disease. The one-carbon metabolism in connection with the hypothalamic-pituitary-adrenal (HPA)-axis may be an important mediator of this increased cardiovascular risk.

METHODS

In a mixed-gender sample of 49 PTSD patients and 45 healthy controls we therefore investigated: (1) alterations in the one-carbon metabolism as reflected in fasting plasma concentrations of homocysteine, folate, vitamins B6 and B12, and (2) associations of these one-carbon metabolites with the HPA-axis hormones cortisol, dehydroepiandrosterone (DHEA) and its sulfate (DHEA-S).

RESULTS

After correction for confounders, PTSD patients had significantly elevated homocysteine (z = 2.963, p = .003) compared to controls, but normal levels of folate, vitamin B6 and B12. Comorbid depression did not explain the observed higher homocysteine levels. Patients showed increased risk for moderate hyperhomocysteinemia (OR = 7.0, χ(2) = 7.436, p = .006). Additionally, homocysteine was associated with PTSD severity (z = 2.281, p = .005). Moreover, all HPA-axis hormones were associated with folate in both patients and controls (all p's ≤ .011), while DHEA-S influenced folate in patients (z = 2.089, p = .037).

LIMITATIONS

Our clinical sample is relatively small and therefore small-sized effects may have remained undetected.

CONCLUSIONS

Our study indicates that: (1) the one-carbon metabolism is altered in PTSD patients, (2) earlier findings of higher homocysteine in male PTSD patients are generalized to female patients, (3) homocysteine is negatively associated with PTSD severity, and (4) HPA-axis alterations are associated with the one-carbon metabolism. Longitudinal studies are needed to determine whether elevated homocysteine levels reflect preexisting risk factors and/or consequences of psychological trauma.

Transient increase in homocysteine but not hyperhomocysteinemia during acute exercise at different intensities in sedentary individuals

Considering that hyperhomocysteinemia is an independent risk factor for cardiovascular disease, the purpose of this study was to determine the kinetics of serum homocysteine (tHcy) and the vitamins involved in its metabolism (folates, B₁₂, and B₆) in response to acute exercise at different intensities. Eight sedentary males (18–27 yr) took part in the study. Subjects were required to complete two isocaloric (400 kcal) acute exercise trials on separate occasions at 40% (low intensity, LI) and 80% VO_2peak (high intensity, HI). Blood samples were drawn at different points before (pre4 and pre0 h), during (exer10, exer20, exer30, exer45, and exer60 min), and after exercise (post0, post3, and post19 h). Dietary, genetic, and lifestyle factors were controlled. Maximum tHcy occurred during exercise, both at LI (8.6 (8.0–10.1) µmol/L, 9.3% increase from pre0) and HI (9.4 (8.2–10.6) µmol/L, 25.7% increase from pre0), coinciding with an accumulated energy expenditure independent of the exercise intensity. From this point onwards tHcy declined until the cessation of exercise and continued descending. At post19, tHcy was not different from pre-exercise values. No values of hyperhomocysteinemia were observed at any sampling point and intensity. In conclusion, acute exercise in sedentary individuals, even at HI, shows no negative effect on tHcy when at least 400 kcal are spent during exercise and the nutritional status for folate, B₁₂, and B₆ is adequate, since no hyperhomocysteinemia has been observed and basal concentrations were recovered in less than 24 h. This could be relevant for further informing healthy exercise recommendations.

Gene polymorphisms in association with emerging cardiovascular risk markers in adult women

Background

Evidence on the associations of emerging cardiovascular disease risk factors/markers with genes may help identify intermediate pathways of disease susceptibility in the general population. This population-based study is aimed to determine the presence of associations between a wide array of genetic variants and emerging cardiovascular risk markers among adult US women.

Methods

The current analysis was performed among the National Health and Nutrition Examination Survey (NHANES) III phase 2 samples of adult women aged 17 years and older (sample size n = 3409). Fourteen candidate genes within ADRB2, ADRB3, CAT, CRP, F2, F5, FGB, ITGB3, MTHFR, NOS3, PON1, PPARG, TLR4, and TNF were examined for associations with emerging cardiovascular risk markers such as serum C-reactive protein, homocysteine, uric acid, and plasma fibrinogen. Linear regression models were performed using SAS-callable SUDAAN 9.0. The covariates included age, race/ethnicity, education, menopausal status, female hormone use, aspirin use, and lifestyle factors.

Results

In covariate-adjusted models, serum C-reactive protein concentrations were significantly (P value controlling for false-discovery rate ≤ 0.05) associated with polymorphisms in CRP (rs3093058, rs1205), MTHFR (rs1801131), and ADRB3 (rs4994). Serum homocysteine levels were significantly associated with MTHFR (rs1801133).

Conclusion

The significant associations between certain gene variants with concentration variations in serum C-reactive protein and homocysteine among adult women need to be confirmed in further genetic association studies.

Cardiovascular disease in women

Cardiovascular disease (CVD) remains the most important health issue facing women and continues to be their number one cause of morbidity and mortality. Women are disproportionately affected by CVD compared with men. It is diagnosed less often and treated less aggressively in the inpatient and outpatient settings; as a result, women have poorer outcomes. It is therefore imperative that physicians take steps to screen women for the risks associated with CVD and actively education them on primary and secondary prevention.

Homocysteine lowering interventions for preventing cardiovascular events

BACKGROUND

Cardiovascular disease such as coronary artery disease, stroke and congestive heart failure, is a leading cause of death worldwide. A postulated risk factor is elevated circulating total homocysteine (tHcy) levels which is influenced mainly by blood levels of cyanocobalamin (vitamin B12), folic acid (vitamin B9) and pyridoxine (vitamin B6). There is uncertainty regarding the strength of association between tHcy and the risk of cardiovascular disease.

OBJECTIVES

To assess the clinical effectiveness of homocysteine-lowering interventions (HLI) in people with or without pre-existing cardiovascular disease.

SEARCH STRATEGY

We searched The Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library (issue 3 2008), MEDLINE (1950 to August 2008), EMBASE (1988 to August 2008), and LILACS (1982 to September 2, 2008). We also searched in Allied and Complementary Medicine (AMED; 1985 to August 2008), ISI Web of Science (1993 to August 2008), and the Cochrane Stroke Group Specialised Register (April 2007). We hand searched pertinent journals and the reference lists of included papers. We also contacted researchers in the field. There was no language restriction in the search.

SELECTION CRITERIA

We included randomised clinical trials (RCTs) assessing the effects of HLI for preventing cardiovascular events with a follow-up period of 1 year or longer. We considered myocardial infarction and stroke as the primary outcomes. We excluded studies in patients with end-stage renal disease.

DATA COLLECTION AND ANALYSIS

We independently performed study selection, risk of bias assessment and data extraction. We estimated relative risks (RR) for dichotomous outcomes. We measured statistical heterogeneity using I(2). We used a random-effects model to synthesise the findings.

MAIN RESULTS

We included eight RCTs involving 24,210 participants with a low risk of bias in general terms. HLI did not reduce the risk of non-fatal or fatal myocardial infarction, stroke, or death by any cause (pooled RR 1.03, 95% CI 0.94 to 1.13, I(2) = 0%; pooled RR 0.89, 95% CI 0.73 to 1.08, I(2) = 15%); and pooled RR 1.00 (95% CI 0.92 to 1.09, I(2): 0%), respectively.

AUTHORS' CONCLUSIONS

Results from available published trials suggest that there is no evidence to support the use of HLI to prevent cardiovascular events.

Hyperhomocysteinemia in epileptic patients on new antiepileptic drugs

PURPOSE

Older enzyme-inducing antiepileptic drugs (AEDs) may induce supraphysiologic plasma concentrations of total (t) homocysteine (Hcy). The aim of the present study was to investigate the effect of new AEDs on plasma tHcy levels.

METHODS

Patients 18-50 years of age, on AEDs monotherapy, with no other known cause of hyper-tHcy were enrolled. Plasma tHcy, folate, vitamin B(12), and AEDs levels were determined by standard high-performance liquid chromatography (HPLC) methods. Methylenetetrahydrofolate-reductase (MTHFR) polymorphisms were checked using Puregene genomic DNA purification system (Gentra, Celbio, Italy). A group of healthy volunteers matched for age and sex was taken as control.

RESULTS

Two hundred fifty-nine patients (151 on newer and 108 on older AEDs) and 231 controls were enrolled. Plasma tHcy levels were significantly higher [mean values, standard error (SE) 16.8, 0.4 vs. 9.1, 0.2 microm; physiologic range 5-13 microm] and folate lower (6.3, 0.1 vs. 9.3, 0.1 nm; normal > 6.8 nm) in patients compared to controls. Patients treated with oxcarbazepine, topiramate, carbamazepine, and phenobarbital exhibited mean plasma tHcy levels above the physiologic range [mean values (SE) 16 (0.8), 19.1 (0.8), 20.5 (1.0), and 18.5 (1.5) microm, respectively]. Conversely, normal tHcy concentrations were observed in the lamotrigine and levetiracetam groups [both 11.1 (0.5) microm].

DISCUSSION

Oxcarbazepine and topiramate might cause hyper-tHcy, most likely because of the capacity of these agents to induce the hepatic enzymes. Because literature data suggest that hyper-tHcy may contribute to the development of cerebrovascular diseases and brain atrophy, a supplement of folate can be considered in these patients to normalize plasma tHcy.

Acute benzodiazepine administration induces changes in homocysteine metabolism in young healthy volunteers

PURPOSE

High cortisol plasma concentrations have been shown to be associated with increases in homocysteine levels. Here we studied whether decreases in cortisol concentration, induced by an acute oral dose of a benzodiazepine, could decrease homocysteine, and if changes were similar in both genders.

METHODS

This was a double-blind, cross-over design study of acute oral flunitrazepam (1.2 mg) and placebo in young, healthy, male and female (n=21) volunteers. Blood samples were collected 3 h after ingestion (after peak-plasma concentration of flunitrazepam was reached). Various biochemical parameters were analysed, such as plasma homocysteine, cysteine, folate, vitamins B6, B12, and sexual hormones.

RESULTS

Flunitrazepam reduced cortisol (p=0.0011), cysteine (p=0.014) and homocysteine (p=0.028) concentrations, irrespective of gender. No correlations were found between cortisol and other biochemical markers (all r's<0.03). Concentration of cysteine and homocysteine were negatively correlated with plasma flunitrazepam concentration, suggesting that changes in these amino acids might be related to the metabolism of this benzodiazepine.

CONCLUSION

Acute administration of flunitrazepam decreases plasma homocysteine and cysteine by mechanisms that seem unrelated to changes in cortisol. Given the importance of homocysteine as a marker of life-threatening disorders, the mechanisms involved in the decrease of these amino acids are potential targets for clinical application.

Homocysteine and serum lipids concentration in male war veterans with posttraumatic stress disorder

The evidence of increased cardiovascular disease (CVD) risk in posttraumatic stress disorder (PTSD) is accumulating. The present study aimed to determine whether chronic, combat-related PTSD is associated with serum lipid and homocysteine concentrations that could indicate higher CVD risk. The authors tested 66 war veterans with PTSD, 33 war veterans without PTSD, and 42 healthy volunteers for serum concentrations of homocysteine, total cholesterol, high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C) and triglycerides. All the subjects were men and the analyses were adjusted for age, body mass index and smoking. Potential influences of depression, anxiety, and psychotic symptoms on the outcome measures were checked by introducing the scores from the Hamilton Depression Rating Scale (HAM-D-17), the Hamilton Anxiety Scale (HAMA), and the Positive and Negative Syndrome Scale (PANSS) into the overall statistical model. No differences in total cholesterol, LDL-C, HDL-C and triglycerides were found between the groups. Non-smoking PTSD war veterans had higher homocysteine concentrations (mean=10.4 micromol/L, SD=1.7) when compared to non-smoking war veterans without PTSD (mean=8.2 micromol/L, SD=4.0, P=0.014) and both smoking (mean=8.7 micromol/L, SD=2.3, P=0.008) and non-smoking healthy volunteers (mean=8.8 micromol/L, SD=2.2, P=0.021). The results of our cross-sectional study are possibly confounded by many factors, especially behavioral and life-style related which are difficult to control comprehensively and might have influenced serum lipids and homocysteine concentration in a complex manner. An increase in the homocysteine concentration observed in the non-smoking PTSD patients needs further investigation with a carefully designed prospective study to confirm associated, possibly enhanced CVD risk.

Considering the inclusion of metabolic and cardiovascular markers in the Panel Study of Income Dynamics

The inclusion of biomarkers in social surveys such as the Panel Study of Income Dynamics (PSID) has the potential to answer many elusive questions in social science and public health, including the much-studied relationship between socioeconomic status and health. This article reviews the potential inclusion of biomarkers of cardiovascular and metabolic risk in the PSID. We first discuss the considerable analytical benefits of adding these biomarkers to the PSID, including the exploration of life course hypotheses and the potential to test causal relationships between the social environment and biological systems. Next, we review evidence on the reliability of self-reports of cardiovascular and metabolic risk factors, concluding that the potential bias from relying on self-reports may be substantial. Based on evidence of biological importance as well as practical considerations of ease of in-home collection, our first tier of recommended biomarkers includes measured height, weight, waist and hip circumference, diastolic and systolic blood pressure, resting heart rate, total and high-density lipoprotein (HDL) cholesterol, glycosylated hemoglobin (HbA1c), C-reactive protein (CRP), and cystatin C. Additional markers of secondary priority are also discussed.