Homocysteine and coronary atherosclerosis: from folate fortification to the recent clinical trials

Association between H-type Hypertension and Asymptomatic Extracranial Artery Stenosis

Asymptomatic extracranial artery stenosis (ECAS) is a well-known risk factor for stroke and H-type hypertension, which is defined as hypertension with hyperhomocysteinemia, is associated with cardio-cerebrovascular diseases. However, the impact of H-type hypertension on ECAS is mostly unknown. We designed this study to investigate the association between H-type hypertension and prevalence of ECAS. We included 2330 participants in this study and classified them into four groups: the control group without hypertension or hyperhomocysteinemia, isolated hypertension group, isolated hyperhomocysteinemia group and H-type hypertension group. We measured the baseline plasma total homocysteine levels and assessed ECAS by carotid duplex sonography twice at baseline and during follow up. We used a Cox regression model to analyse the association between H-type hypertension and ECAS. At baseline, 608 subjects suffered from H-type hypertension. Within two years of follow-up, asymptomatic ECAS occurred in 250 (10.73%) participants. After adjusting for relevant risk factors, we found H-type hypertension to be an independent risk factor for asymptomatic ECAS (relative risk (RR) 3.16, 95% confidence interval (95% CI) 2.00-5.00). Our findings provide direct evidence for the importance of H-type hypertension in the occurrence of ECAS and as a potential therapeutic target for carotid atherosclerosis.

The association between plasma homocysteine and ambulatory blood pressure variability in patients with untreated hypertension

BACKGROUND

Both homocysteine (Hcy) and blood pressure variability (BPV) are independent predictors of stroke, however, their relationship is rarely evaluated before. This study aimed to investigate the association Hcy and ambulatory BPV in subjects with untreated primary hypertension.

METHODS

A total of 252 eligible patients were recruited. Plasma Hcy was measured and 24-h ambulatory blood pressure monitoring was performed for each subject. The systolic and diastolic BPV values were calculated as the SD of individual blood pressure values during 24h, daytime and nighttime, and then stratified by the tertiles of Hcy concentration (T1 to T3). Univariate and multivariate linear regression models were used to assess the relationships between Hcy tertiles and BPV variables.

RESULTS

The mean values of Hcy from T1 to T3 were 7.51±1.21μmol/l, 11.09±1.07μmol/l and 19.14±6.26μmol/l, respectively. Systolic and diastolic mean blood pressures were similar among subjects with different Hcy tertiles. However, both systolic and diastolic BPV variables, no matter in 24-h, daytime or nighttime, were increasing significantly along with the rises in Hcy tertiles (all p<0.05 for linear trends analysis). Multivariate linear regression analysis indicated that Hcy tertiles were significantly associated with BPV variables, independently of mean blood pressures other confounding factors. In subgroup analysis, the associations between Hcy tertiles and BPV variables were enhanced by the increased risk stratification of hypertension.

CONCLUSIONS

Plasma Hcy was positively and independently associated with ambulatory BPV in patients with untreated hypertension.

Correlation of Maternal Serum Homocysteine in the First Trimester with the Development of Gestational Hypertension and Preeclampsia

Background

This study investigated the relationship of serum homocysteine in early pregnancy with the risk of gestational hypertension (GH) and preeclampsia (PE) and with the severity of preeclampsia.

Material/Methods

In a retrospective cohort study, we identified 147 confirmed cases of preeclampsia (103 with mild PE and 44 with severe PE) and 147 confirmed cases of GH; 4418 women who remained normotensive and nonproteinuric throughout pregnancy served as controls. Maternal blood samples were collected at between 11 and 13 weeks of gestation to test serum concentrations of homocysteine (Hcy), folic acid, and VitB12. A logistic regression model was used to calculate adjusted odds ratios (aORs) and 95% confidence intervals (CIs).

Results

Women who subsequently developed GH and PE were older and had higher body mass indexes (BMIs) than those in the control group. Compared with the control group, women who developed PE were less educated (P=0.031), and more of those who developed GH were primiparas (P=0.012). The serum levels of Hcy in severe PE were significantly higher than those in the control group (median: 8.50 μmol/L vs. 7.33 μmol/L, P<0.001). After logistic regression analyses for potential confounding factors, the adjusted odds ratios (aORs) of Hcy was 1.12 for severe PE (95% CI 1.06–1.20). The serum concentrations of folic acid and VitB12 in those with GH and PE were not significantly different from controls.

Conclusions

A high level of Hcy in the first trimester is an independent risk factor for severe PE, although it is not a useful marker for the subsequent development of GH and mild PE.

Folic Acid Supplementation for Stroke Prevention in Patients With Cardiovascular Disease

BACKGROUND

Controversy remains regarding the efficacy of folic acid supplementation in reducing the risk of stroke. This study aimed to evaluate the effect of folic acid supplementation on stroke prevention in patients with cardiovascular disease (CVD).

MATERIALS AND METHODS

We searched the PubMed, EMBASE and Cochrane Library databases through October 2016 to identify randomized clinical trials of folic acid supplementation to prevent stroke in patients with CVD. Relative risks (RRs) with 95% CIs were used to examine the association between folic acid supplementation and the risk of stroke with a fixed-effect model. Stratified analyses were performed according to modifiers that may affect the efficacy of folic acid supplementation.

RESULTS

Eleven studies with a total of 65,790 participants were included. Folic acid supplementation was associated with a significant benefit in reducing the risk of stroke in patients with CVD (RR = 0.90; 95% CI: 0.84-0.97; P = 0.005). In the stratified analysis, greater beneficial effects were observed in participants with a decrease in homocysteine concentrations of 25% or greater (RR = 0.85; 95% CI: 0.74-0.97; P = 0.03), those with a daily folate dose of less than 2mg (RR = 0.78; 95% CI: 0.68-0.89; P = 0.01), and populations in regions with no or partly fortified grain (RR = 0.87; 95% CI: 0.81-0.94; P = 0.04).

CONCLUSIONS

Our meta-analysis demonstrated that folic acid supplementation is effective in stroke prevention in patients with CVD.

Homocysteine in non-valvular atrial fibrillation: Role and clinical implications

Atrial fibrillation (AF), the most common sustained arrhythmia, is associated with a series of adverse complications that cause so-called AF socioeconomic burden. Apart from the classical risk factors, it seems to be novel factors that increase the risk of AF and AF-related stroke. Recently, more and more evidence has well documented the close relationships between homocysteine (Hcy) and AF. As a well-known marker for pro-oxidation and pro-inflammation, Hcy plays an important role in a number of vascular diseases having strong association with AF. This review will discuss the expression of Hcy and its association with ischemic stroke in AF patients especially for elderly patients, and the role and clinical implications of Hcy in the thromboembolic events and rhythm outcome in AF patients. The possible mechanisms linking elevated Hcy and cardiovascular events in AF patients will also be addressed, including oxidative stress, inflammatory response, atrial remodeling, etc.

EFFECT OF PROBIOTIC FERMENTED MILK (KEFIR) ON SERUM LEVEL OF INSULIN AND HOMOCYSTEINE IN TYPE 2 DIABETES PATIENTS

BACKGROUND

Probiotic fermented milk is one of the most beneficial foods. The main purpose of this study was to investigate the effect of probiotic fermented milk on the serum level of insulin and homocysteine in the type 2 diabetes patients.

METHODS

This study was done in 60 patients with type 2 diabetes. The intervention group received 600 mL of probiotic fermented milk (kefir) daily and control group received 600 mL of conventional fermented milk daily for 8 weeks. Food intake, anthropometric indices, serum parameters were assessed at the beginning and at the end of the study. The statistical analysis was done by the use of SPSS software (Ver.13).

RESULTS

The mean of serum insulin level did not reduce significantly after the intervention in probiotic fermented milk group, and there was no significant difference between the two groups. The mean of HOMA-IR decreased significantly in probiotic fermented milk group after intervention and there was a significant difference between the two groups after intervention. The mean of quickie increased in probiotic fermented milk group, but this increase was not significant. Also, there was not significant difference between the two groups after intervention. The mean of homocysteine level decresead significantly in patients with probiotic fermented milk and conventional fermented milk consumption.

CONCLUSIONS

By considering the effect of probiotic fermented milk on some risk factors of cardiovascular disease in diabetic patients, probiotic foods may be useful as an adjuvant therapy in diabetic patients.

The Impact of Supplementation with Folic Acid on Homocysteine Concentration and Selected Lipoprotein Parameters in Patients with Primary Hypertension

The aim of the study was the assessment of the impact of supplementation with folic acid on the concentration of homocysteine, total cholesterol (TC), HDL- and LDL-cholesterol, triglycerides (TG), apoprotein AI (apoAI) and apoprotein B (apoB) in patients suffering from primary hypertension. The examined group comprised 42 patients suffering from primary hypertension. All examined patients underwent laboratory tests as follows: concentration of homocysteine, folic acid, TC, LDL-cholesterol, HDL-cholesterol, TG, apoAI and apoB. All patients were orally administered with 15 mg of folic acid per day for 45 d. After this period, all laboratory tests were repeated. Homocysteine concentration was measured by the FPIA method, concentrations of apoAI and apoB were measured by the nephelometric method, and other parameters with routine methods. After administration of 15 mg of folic acid to patients with primary hypertension, a considerable decrease in the concentration of homocysteine was observed in parallel with a substantive growth of HDL-cholesterol, as well as apoprotein AI concentrations and a reduction of the apoprotein B concentration. Results of statistical analysis indicated a significant correlation between the decline in homocysteine concentration and the increase in HDL-cholesterol concentration, as well as between the increase of folic acid concentration and the increase in apoAI concentration in patients following the intake of folic acid. The drop in homocysteine concentration through the supplementation with folic acid can cause quantitative changes in the lipid and lipoprotein parameters which, in consequence, may lead to the mitigation of risk concerning the development of atherosclerosis.

Activation of PERK branch of ER stress mediates homocysteine-induced BKCa channel dysfunction in coronary artery via FoxO3a-dependent regulation of atrogin-1

The molecular mechanism of endoplasmic reticulum (ER) stress in vascular pathophysiology remains inadequately understood. We studied the role of ER stress in homocysteine-induced impairment of coronary dilator function, with uncovering the molecular basis of the effect of ER stress on smooth muscle large-conductance Ca²⁺-activated K⁺ (BK_Ca) channels. The vasodilatory function of BK_Ca channels was studied in a myograph using endothelium-denuded porcine small coronary arteries. Primary cultured porcine coronary artery smooth muscle cells were used for mRNA and protein measurements and current recording of BK_Ca channels. Homocysteine inhibited vasorelaxant response to the BK_Cachannel opener NS1619, lowered BK_Ca β1 subunit protein level and suppressed BK_Ca current. Inhibition of ER stress restored BK_Ca β1 protein level and NS1619-evoked vasorelaxation. Selective blockade of the PKR-like ER kinase (PERK) yielded similarly efficient restoration of BK_Ca β1, preserving BK_Ca current and BK_Ca-mediated vasorelaxation. The restoration of BK_Ca β1 by PERK inhibition was associated with reduced atrogin-1 expression and decreased nuclear localization of forkhead box O transcription factor 3a (FoxO3a). Silencing of atrogin-1 prevented homocysteine-induced BK_Ca β1 loss and silencing of FoxO3a prevented atrogin-1 upregulation induced by homocysteine, accompanied by preservation of BK_Ca β1 protein level and BK_Ca current. ER stress mediates homocysteine-induced BK_Ca channel inhibition in coronary arteries. Activation of FoxO3a by PERK branch underlies the ER stress-mediated BK_Ca inhibition through a mechanism involving ubiquitin ligase-enhanced degradation of the channel β1 subunit.

Association between plasma homocysteine concentration and the risk of all-cause death in adults with diastolic dysfunction in a community: A 13-year cohort study

Hyperhomocysteinemia (HHCYS) has been associated with systolic heart failure. However, it is still unknown that serum homocycsteine level was useful in predicting the outcome in patients with diastolic dysfunction. We conducted a cohort study to determine if HHCYS was associated with poor prognosis in diastolic dysfunction patients. The Chin-Shan Community Cardiovascular Cohort (CCCC) study was designated to investigate the trends of cardiovascular morbidity and mortality in a community. Individuals who were 35 years and above were enrolled. Participants were categorized by homocysteine concentration quartiles. We used multivariate Cox proportional hazards models to calculate the hazard ratio (HR) of the 4th quartiles versus the 1st quartile. Area under the receiver-operating characteristic (ROC) curve was to compare prediction measures. A total of 2020 participants had completed the echocardiography examination, and 231 individuals were diagnosed as diastolic dysfunction. A total 75 participants had died during follow-up period. HHCYS was found to be significantly associated with poor prognosis. The adjusted HR for homocysteine level was 1.07 (95% confidence interval [CI], 1.01-1.14). Participants in the highest quartile had a 1.90 (95% CI, 0.88-4.12, P for trend, .026) fold risk for all cause death, compared with those in the lowest quartiles. The HR was 1.88 (95% CI, 1.07-3.29) using 11.11 μmol/L as cut point for hyperhomocysteine. HHCYS was significantly associated with poor prognosis in diastolic dysfunction participants in the community.

Relationship between plasma homocysteine level and lipid profiles in a community-based Chinese population

Background

Previous studies established a possible link among hyperhomocysteinemia (HHcy), dyslipidemia, and atherosclerosis. However, there was limited epidemic data concerning the relation between HHcy and lipid profiles, especially in community-based Chinese populations. This study aim to investigate the association of plasma homocysteine (Hcy) level with lipid profiles in a Chinese community-based population without lipid-lowering treatment.

Method

A total of 4660 Chinese subjects from a cohort of the Shijingshan district in Beijing were included in the analysis. Plasma total Hcy, serum lipid files including total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) as well as relevant metabolic risk factors were measured. Multivariate regression models adjusting for age, gender, smoking, drinking, physical activity, vitamin B supplement, body mass index, fasting blood glucose level, serum creatinine, systolic and diastolic blood pressure were used to evaluate associations of Hcy and lipid profiles.

Result

Subjects were 56.75 ± 8.91 years old, and 38.15% were male. Median (IQR) Hcy was 11.98 (10.00–14.93) μmol/L, and 24.4% had HHcy (defined as Hcy ≥ 15 μmol/L). Mean (SD) baseline TC was 5.34 ± 0.98 mmol/L, LDL-C was 3.27 ± 0.81 mmol/L, and HDL-C was 1.43 ± 0.38 mmol/L. Median (IQR) of TG was 1.28 (0.91–1.85) mmol/L. In multivariable linear-regression analyses, lnHcy (ln transformation for Hcy) level was positively associated with lnTG (adjusted β = 0.075, SE = 0.021, P = 0.001). Using Hcy < 15 μmol/L as a reference, HHcy was independently associated with both lnTG (adjusted β = 0.056, SE = 0.020, P = 0.004) and lnHDL (adjusted β = −0.018, SE = 0.009, P = 0.038). In multivariable logistic-regression analyses, HHcy was associated with increasing risk of low HDL-C (HDL-C < 1.04 mmol/L; adjusted odds ratio [OR] =1.406, 95% confidence interval [CI]: 1.143 – 1.728, P = 0.001) and hypertriglyceridemia (TG ≥ 1.7 mmol/L; adjusted OR = 1.293, 95% CI: 1.096–1.524, P = 0.002) after adjusting the confounders. However, there were no significant associations between Hcy and TC or LDL-C.

Conclusion

The present study showed that HHcy was independently associated with hypertriglyceridemia and low levels of HDL-C, which provides evidence that Hcy levels might affect HDL-C and TG metabolism.

What people with Down Syndrome can teach us about cardiopulmonary disease

Down syndrome is the most common chromosomal abnormality among live-born infants. Through full or partial trisomy of chromosome 21, Down syndrome is associated with cognitive impairment, congenital malformations (particularly cardiovascular) and dysmorphic features. Immune disturbances in Down syndrome account for an enormous disease burden ranging from quality-of-life issues (autoimmune alopecia) to more serious health issues (autoimmune thyroiditis) and life-threatening issues (leukaemia, respiratory tract infections and pulmonary hypertension). Cardiovascular and pulmonary diseases account for ∼75% of the mortality seen in persons with Down syndrome. This review summarises the cardiovascular, respiratory and immune challenges faced by individuals with Down syndrome, and the genetic underpinnings of their pathobiology. We strongly advocate increased comparative studies of cardiopulmonary disease in persons with and without Down syndrome, as we believe these will lead to new strategies to prevent and treat diseases affecting millions of people worldwide.

Abdominal aortic aneurysm-an independent disease to atherosclerosis?

Atherosclerosis and abdominal aortic aneurysms (AAAs) are multifactorial and polygenic diseases with known environmental and genetic risk factors that contribute toward disease development. Atherosclerosis represents an important independent risk factor for AAA, as people with AAA often have atherosclerosis. Studies have shown that comorbidity is usually between ~25% and 55%, but it is still not fully known whether this association is causal or a result of common shared risk profiles. Most recent epidemiological, clinical, and biological evidence suggests that the two pathologies are more distinct than traditionally thought. For instance diabetes mellitus, hypercholesterolemia, and obesity are high risk for atherosclerosis development but are not as pronounced in AAA, whereas smoking, gender, and ethnicity are particularly high risk for AAA but less so for atherosclerosis. In addition, genetic and epigenetic studies have identified independent risk loci involved in AAA susceptibility that are not associated with other cardiovascular diseases, and research on important common cardiovascular biomarkers has illustrated discrepancies in those with AAA.

Serum high concentrations of homocysteine and low levels of folic acid and vitamin B12 are significantly correlated with the categories of coronary artery diseases

Background

Homocysteine (Hcy) has been considered as an independent risk factor for coronary artery disease (CAD). Folic acid and vitamin B₁₂ are two vital regulators in Hcy metabolic process. We evaluated the correlations between serum Hcy, folic acid and vitamin B₁₂ with the categories of CAD.

Methods

Serum Hcy, folic acid and vitamin B₁₂ from 292 CAD patients, including 73 acute myocardial infarction (AMI), 116 unstable angina pectoris (UAP), 103 stable angina pectoris (SAP), and 100 controls with chest pain patients were measured, and the data were analyzed by SPSS software.

Results

Compared to SAP patients, patients with AMI and UAP had higher Hcy levels with approximately average elevated (4-5) μmol/L, while SAP patients were approximately higher 8 μmol/L than controls. However, the levels of folic acid and vitamin B₁₂ had opposite results, which in AMI group was the lowest, while in controls was the highest. CAD categories were positively correlated with Hcy (r = 0.286, p < 0.001), and negatively correlated with folic acid (r = -0.297, p < 0.001) and vitamin B₁₂ (r = -0.208, p < 0.001). There were significant trend toward increase in the prevalence of high Hcy, low folic acid and vitamin B₁₂ from controls, to SAP, to UAP, and to AMI.

Conclusions

The present study provide the valuable evidence that high concentrations of Hcy and low levels of folic acid and vitamin B₁₂ are significantly correlated with CAD categories.

Hyperhomocysteinemia causes ER stress and impaired autophagy that is reversed by Vitamin B supplementation

Hyperhomocysteinemia (HHcy) is a well-known risk factor for stroke; however, its underlying molecular mechanism remains unclear. Using both mouse and cell culture models, we have provided evidence that impairment of autophagy has a central role in HHcy-induced cellular injury in the mouse brain. We observed accumulation of LC3B-II and p62 that was associated with increased MTOR signaling in human and mouse primary astrocyte cell cultures as well as a diet-induced mouse model of HHcy, HHcy decreased lysosomal membrane protein LAMP2, vacuolar ATPase (ATP6V0A2), and protease cathepsin D, suggesting that lysosomal dysfunction also contributed to the autophagic defect. Moreover, HHcy increased unfolded protein response. Interestingly, Vitamin B supplementation restored autophagic flux, alleviated ER stress, and reversed lysosomal dysfunction due to HHCy. Furthermore, the autophagy inducer, rapamycin was able to relieve ER stress and reverse lysosomal dysfunction caused by HHcy in vitro. Inhibition of autophagy by HHcy exacerbated cellular injury during oxygen and glucose deprivation and reperfusion (OGD/R), and oxidative stress. These effects were prevented by Vitamin B co-treatment, suggesting that it may be helpful in relieving detrimental effects of HHcy in ischemia/reperfusion or oxidative stress. Collectively, these findings show that Vitamin B therapy can reverse defects in cellular autophagy and ER stress due to HHcy; and thus may be a potential treatment to reduce ischemic damage caused by stroke in patients with HHcy.

Relationship between cardio-ankle vascular index and homocysteine in hypertension subjects with hyperhomocysteinemia

BACKGROUND

Arteriosclerosis evaluated by arterial stiffness is the basic pathophysiological change during the development of hypertension. Cardio-ankle vascular index (CAVI) is an index of arterial stiffness. Hyperhomocysteinemia (HHcy) is an independent risk factor for vascular diseases. However, there was little research about the relationship between CAVI and homocysteine (Hcy) in hypertension subjects with HHcy.

METHODS

A total of 330 subjects (M/F 133/197) from Vascular Medicine of Peking University Shougang Hospital were divided into four groups: control group (group 1, normotensive with normal Hcy, n = 149), hypertension group (group 2, n = 113), HHcy group (group 3, n = 30), and hypertension with HHcy group (group 4, n = 38). CAVI was measured by VS-1000 apparatus.

RESULTS

Our results showed that CAVI was significantly higher in group 4 than in group 1 and group 2 (8.41 ± 1.08 vs. 7.79 ± 1.14; 8.41 ± 1.08 vs. 7.87 ± 1.02, both p < 0.05, respectively). Positive correlation between CAVI and Hcy was found in the entire study group (r = 0.109, p = 0.049) and hypertension subjects (group 2 + group 4; r = 0.202, p = 0.014). Multivariate analysis showed that Hcy was an independent associating factor of CAVI in all subjects (β = 0.251, p = 0.034).

CONCLUSIONS

The present study showed that CAVI was significantly higher in hypertension subjects with HHcy compared to hypertension group. There was significant correlation between CAVI and Hcy, indicating the relationship between arterial stiffness and biomarkers in vascular-related diseases.

Clinical significance of hyperhomocysteinemia in infective endocarditis: A case-control study

Blood coagulation plays a key role in the pathogenesis of infective endocarditis (IE). Conditions associated with thrombophilia could enhance IE vegetation formation and promote embolic complications.In this study, we assessed prevalence, correlates, and clinical consequences of hyper-homocysteinemia (h-Hcy) in IE.Homocysteine (Hcy) plasma levels were studied in 246 IE patients and 258 valvular heart disease (VHD) patients, as well as in 106 healthy controls.IE patients showed Hcy levels comparable to VHD patients (14.9 [3-81] vs 16 [5-50] μmol/L, respectively; P = 0.08). H-Hcy was observed in 48.8% of IE patients and 55.8% of VHD (P = 0.13). Vegetation size and major embolic complications were not related to Hcy levels. IE patients with h-Hcy had a higher prevalence of chronic kidney disease and a higher 1-year mortality (19.6% vs 9.9% in those without h-Hcy; OR 2.21 [1.00-4.89], P = 0.05). However, at logistic regression analysis, h-Hcy was not an independent predictor of 1-year mortality (OR 1.87 [95% CI 0.8-4.2]; P = 0.13).Our data suggest h-Hcy in IE is common, is related to a worse renal function, and may be a marker of cardiac dysfunction rather than infection. H-Hcy does not appear to favor IE vegetation formation or its symptomatic embolic complications.

Increased homocysteine plasma level is associated with shortened prothrombin time in HIV-infected patients

OBJECTIVE

To find factors associated with increased homocysteine plasma level in HIV-infected patients.

METHODS

Cross-sectional study, carried out as a supplementary task to the standard care of HIV-infected patients. The possible association of increased homocysteine plasma level with blood analyses results was assessed with a multiple linear regression analysis, using the automatic linear modeling available in SPSS version 22.

RESULTS

A total of 145 patients were included. Creatinine was higher than normal in 7 patients (5%), prothrombin time was shortened in 36 patients (25%), and a monoclonal gammopathy was detected in 2 patients (1%). In the regression analysis, an association was found between high homocysteine plasma level and the following variables: low prothrombin time (β coefficient -0.286, confidence interval -1.1854 to -0.754, p < 0.001), high creatinine (coefficient 9.926, confidence interval 6.351-15.246, p < 0.001), low folic acid (coefficient -0.331, confidence interval -0-483 to -0.187, p < 0.001), and low vitamin B12 (coefficient -0.007, confidence interval -0.01 to -0.001, p = 0.005).

CONCLUSION

An association was found between increased homocysteine plasma level and shortened prothrombin time.

The relationship between serum paraoxonase levels and carotid atherosclerotic plaque formation in Alzheimer's patients

Low paraoxonase 1 (PON1) activity and carotid atherosclerosis have been suggested to be important risk factors for dementia. However, the studies to date could not fully clarify the relationship between PON1, carotid atherosclerosis and dementia. The present study aimed to measure carotid atherosclerosis and PON1 activity in Alzheimer's Disease and to evaluate the relationship between them. The study included 25 Alzheimer's patients and 25 control subjects, for a total of 50 individuals. The study measured the serum PON1 activity and other biochemical parameters and carotid atherosclerotic plaque values of the participants. The mean paraoxonase activity (31.06±2.31U/L) was significantly lower in the Alzheimer's group compared to the control group (59.05±7.05U/L) (P<0.001). Nonetheless, the carotid plaque values were significantly higher in the patient group (3.02±0.52mm) compared to the control group (1.84±0.45mm) (P<0.001). Furthermore, there was a negative correlation (81.0%) between PON1 activity and carotid plaque in the overall study group (P<0.05). Also serum homocystein level was higher in the patient group (22.15±7.05) compared to the control group (13.30±3.32). In conclusion, our findings show inverse association between PON1 activity and carotid atherosclerosis in Alzheimer patients: the lower the PON1 activity the more progressed the atherosclerotic process in AD.

Potential Risk Factors Associated With Vascular Diseases in Patients Receiving Treatment for Hypertension

Background

Currently, the hypertension (HTN) patients undergo appropriate medical treatment, and traditional risk factors are highly controlled. Therefore, potential risk factors of atherosclerotic vascular diseases (AVD) and venous thromboembolisms (VTE) in HTN should be reconsidered. We investigated thrombophilic genetic mutations and existing biomarkers for AVD or VTE in HTN patients receiving treatment.

Methods

A total of 183 patients were enrolled: AVD with HTN (group A, n=45), VTE with HTN (group B, n=62), and HTN patients without any vascular diseases (group C, n=76). The lipid profile, homocysteine (Hcy) levels, D-dimers, fibrinogen, antithrombin, lupus anticoagulant, and anti-cardiolipin antibody (aCL) were evaluated. Prothrombin G20210A, Factor V G1691A, and methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C were analyzed.

Results

All patients revealed wild type prothrombin G20210A and Factor V G1691A polymorphisms. The frequency of MTHFR polymorphisms was 677CT (n=84, 45.9%); 677TT (n=46, 25.1%); 1298AC (n=46, 25.1%); and 1298CC (n=2, 1.1%). The MTHFR 677TT genotype tended to increase the odds ratio (OR) to AVD events in HTN patients (OR 2.648, confidence interval 0.982-7.143, P=0.05). The group A demonstrated significantly higher Hcy levels (P=0.009), fibrinogen (P=0.004), and platelet counts (P=0.04) than group C. Group B had significantly higher levels of D-dimers (P=0.0001), platelet count (P=0.0002), and aCL (P=0.02) frequency than group C.

Conclusions

The MTHFR 677TT genotype and Hcy level could be potential risk factors associated with development of AVD in HTN patients receiving treatment. D-dimer and aCL might be useful to estimate the occurrence of VTE in them.

Mendelian randomisation study of the associations of vitamin B12 and folate genetic risk scores with blood pressure and fasting serum lipid levels in three Danish population-based studies

BACKGROUND/OBJECTIVES

The aim was to examine the association of genetic risk scores (GRSs) of vitamin B12 and folate-associated variants with blood pressure and lipids.

SUBJECTS/METHODS

The study included 12 532 adults from three population-based studies (Inter99, Health2006 and Dan-MONICA10) conducted in Denmark. GRSs were calculated by summarising the number of vitamin B12 and folate increasing alleles. Weighted GRSs were calculated as the sum of weights for each allele corresponding to genetic effects sizes.

RESULTS

GRSs for serum vitamin B12 and folate were associated with serum vitamin B12 and folate, respectively. The β coefficients (95% confidence interval (CI), P-value) for regression of log-transformed serum B12/folate on the weighted GRSs were 0.57 (0.54, 0.61), P<0.001 and 0.85 (0.70, 1.01), P<0.01. No associations were observed between the vitamin B12 GRSs and any of the blood pressure and lipid-related outcomes in the combined analyses. Increasing number of folate increasing alleles was associated with increased high-density lipoprotein (HDL) cholesterol concentrations (β coefficient (95% CI, P-value) for regression of log-transformed HDL on the weighted GRSs, 0.081 (0.015, 0.148), P=0.017), but not with blood pressure, triglyceride, and low-density lipoprotein and total cholesterol levels.

CONCLUSIONS

GRSs were not associated with blood pressure and lipid levels, except for an association between the GRS for folate and HDL cholesterol. Further studies are needed to determine whether a causal association between folate and HDL cholesterol exists.

Multiple biomarkers for mortality prediction in peripheral arterial disease

Few studies have assessed which biomarkers influence mortality risk among those with peripheral arterial disease (PAD). We analyzed data from 556 individuals identified to have PAD (i.e. ankle–brachial index ⩽0.9) with available measurements of C-reactive protein, the neutrophil-to-lymphocyte ratio (NLR), homocysteine, and the urinary albumin-to-creatinine ratio (UACR) in the 1999–2004 National Health and Nutrition Examination Survey. We investigated whether a combination of these biomarkers improved the prediction of all-cause and cardiovascular mortality beyond conventional risk factors. During follow-up (median, 8.1 years), 277 of 556 participants died; 63 deaths were attributed to cardiovascular disease. After adjusting for conventional risk factors, Cox proportional-hazards models showed the following to be most strongly associated with all-cause mortality (each is followed by the adjusted hazard ratio [HR] per 1 standard deviation increment in the log values): homocysteine (1.31), UACR (1.21), and NLR (1.20). UACR alone significantly predicted cardiovascular mortality (1.53). Persons in the highest quintile of multimarker scores derived from regression coefficients of significant biomarkers had elevated risks of all-cause mortality (adjusted HR, 2.45; 95% CI, 1.66–3.62; p for trend, <0.001) and cardiovascular mortality (adjusted HR, 2.20; 95% CI, 1.02–4.71; p for trend, 0.053) compared to those in the lowest two quintiles. The addition of continuous multimarker scores to conventional risk factors improved risk stratification of all-cause mortality (integrated discrimination improvement [IDI], 0.162; p<0.00001) and cardiovascular mortality (IDI, 0.058; p<0.00001). In conclusion, the addition of a continuous multimarker score to conventional risk factors improved mortality prediction among patients with PAD.

Oxidative stress and early atherosclerosis: novel antioxidant treatment

Atherosclerotic lesions initiate in regions characterized by low shear stress and reduced activity of endothelial atheroprotective molecules such as nitric oxide, which is the key molecule managing vascular homeostasis. The generation of reactive oxygen species from the vascular endothelium is strongly related to various enzymes, such as xanthine oxidase, endothelial nitric oxide synthase and nicotinamide-adenine dinucleotide phosphate oxidase. Several pharmaceutical agents, including angiotensin converting enzyme inhibitors, angiotensin receptors blockers and statins, along with a variety of other agents, have demonstrated additional antioxidant properties beyond their principal role. Reports regarding the antioxidant role of vitamins present controversial results, especially those based on large scale studies. In addition, there is growing interest on the role of dietary flavonoids and their potential to improve endothelial function by modifying the oxidative stress status. However, the vascular-protective role of flavonoids and especially their antioxidant properties are still under investigation. Indeed, further research is required to establish the impact of the proposed new therapeutic strategies in atherosclerosis.

Oral N-acetylcysteine reduces plasma homocysteine concentrations regardless of lipid or smoking status

BACKGROUND

Elevated total plasma homocysteine (tHcy) is considered to be an independent cardiovascular disease risk factor, although tHcy lowering by B-vitamins improves only certain clinical endpoints. N-acetylcysteine (NAC), a thiol-containing antioxidant, acutely lowers tHcy and possibly also blood pressure. However, to our knowledge, at present no conclusive long-term evaluation exists that controls for factors such as hyperlipidemia, smoking, medication, and disease stage, all of which affect the thiol redox state, including tHcy.

OBJECTIVE

We reanalyzed 2 double-blind, placebo-controlled trials in unmedicated middle-aged men, one in a hyperlipidemic group (HYL group; n = 40) and one in a normolipidemic group (NOL group; n = 42), each stratified for smokers and nonsmokers.

DESIGN

We evaluated the effect of 4 wk of oral NAC (1.8 g/d) on tHcy (primary endpoint), plasma thiol (cysteine), and intracellular glutathione concentrations as well as on blood pressure. The HYL group had total cholesterol >220 mg/dL or triglycerides >150 mg/dL.

RESULTS

NAC treatment significantly (P = 0.001, multivariate analysis of variance for repeated measures) lowered postabsorptive plasma concentrations of tHcy by -11.7% ± 3.0% (placebo: 4.1% ± 3.6%) while increasing those of cysteine by 28.1% ± 5.7% (placebo: 4.0% ± 3.4%) with no significant impact of hyperlipidemia or smoking. Moreover, NAC significantly decreased systolic (P = 0.003) and diastolic (P = 0.017) blood pressure within all subjects with a significant reduction in diastolic pressure in the HYL group (P = 0.008) but not in the NOL group. An explorative stepwise multiple regression analysis identified 1) post-treatment cysteine as well as 2) pretreatment tHcy and 3) albumin plasma concentrations as being significant contributors to tHcy reduction.

CONCLUSIONS

Four weeks of oral NAC treatment significantly decreased plasma tHcy concentrations, irrespective of lipid or smoking status, and lowered systolic blood pressure in both normolipidemic and hyperlipidemic men, with significant diastolic blood pressure reductions in the HYL group only. Increased oral intake of cysteine may therefore be considered for primary or secondary prevention of vascular events with regard to the 2 independent risk factors of hyperhomocysteinemia and arterial hypertension.

Egg Consumption and Human Cardio-Metabolic Health in People with and without Diabetes

The guidelines for dietary cholesterol and/or egg intake for both the general population and those at higher risk of cardiovascular disease (for example, people with type 2 diabetes mellitus (T2DM)) differ between countries, and even for different specialist societies in a country. The disparity between these guidelines is at least in part related to the conflicting evidence as to the effects of eggs in the general population and in those with T2DM. This review addresses the effect of eggs on cardiovascular disease (CVD) risk from both epidemiological research and controlled prospective studies, in people with and without cardio-metabolic disease. It also examines the nutritional qualities of eggs and whether they may offer protection against chronic disease. The evidence suggests that a diet including more eggs than is recommended (at least in some countries) may be used safely as part of a healthy diet in both the general population and for those at high risk of cardiovascular disease, those with established coronary heart disease, and those with T2DM. In conclusion, an approach focused on a person's entire dietary intake as opposed to specific foods or nutrients should be the heart of population nutrition guidelines.

Associations between plasma total homocysteine, blood pressure stages and pulse wave velocity in Chinese rural community population

The aim of the study was to examine the associations among plasma total homocysteine (tHcy) and blood pressure (BP) stages and brachial-ankle pulse wave velocity (ba-PWV) in a Chinese rural community population. In this cross-sectional study, 2148 rural community subjects with normotension and mild hypertension (HTN) were classified into four groups according to ba-PWV level. Multivariate regression showed that ba-PWV was significantly and independently correlated with tHcy (β = 5.32, p < 0.001) in the entire study population. Moreover, ba-PWV showed a significant increase with increasing plasma tHcy level in subjects with both high normal BP and grade 1 HTN (p < 0.05). Compared with optimal BP stage, ba-PWV was significantly associated with high normal BP stage (β = 193, p < 0.001) and grade 1 HTN (β = 413, p < 0.001).There was a statistical interaction effect between high normal BP stage and optimal BP stage (p = 0.045). The similar result was found between subjects with optimal BP and those with grade 1 HTN (p = 0.037). In conclusion, tHcy was independently correlated with ba-PWV in subjects with high normal BP and grade 1 HTN. High normal BP and grade 1 HTN may worsen the impact of tHcy on arterial stiffness in a Chinese rural community population.

Early life lipid profile and metabolic programming in very young children

BACKGROUND AND AIMS

Lipid derangements during early postnatal life may induce stable epigenetic changes and alter metabolic programming. We investigated associations between serum lipid profiles in very young children and DNA methylation of tumor necrosis factor-alpha (TNFα) and leptin (LEP). Secondly, we explored if the maternal serum lipid profile modifies DNA methylation in the child.

METHODS AND RESULTS

In 120 healthy children at 17 months of age, DNA methylation of TNFα and LEP was measured in DNA derived from whole blood. Linear mixed models were used to calculate exposure-specific differences and associations. Total cholesterol in children was associated with decreased methylation of TNFα (-5.8%, p = 0.036), and HDL-cholesterol was associated with decreased methylation of both TNFα (-6.9%, p = 0.013) and LEP (-3.4%, p = 0.021). Additional adjustment for gestational age at birth, birth weight, sex, breastfeeding and educational level attenuated the effects, TNFα (-6.1%, p = 0.058) and LEP (-3.1%, p = 0.041). In mothers, HDL-cholesterol only was associated with decreased methylation of TNFα in the child (-8.7%, p = 0.001).

CONCLUSION

Our data support the developmental origin of health and disease hypothesis by showing that total cholesterol and HDL-cholesterol levels in very young children are associated with epigenetic metabolic programming, which may affect their vulnerability for developing cardiovascular diseases in later life.

Acute Myocardial Infarction in a Young Lady due to Vitamin B12 Deficiency Induced Hyperhomocysteinemia

Hyper-homocysteinemia is a risk factor for coronary artery disease in young patients. A 32 years old female without any conventional risk factors except obesity presented with acute anterior wall myocardial infarction (MI). Her echocardiography showed anterior wall hypokinesia with moderate left ventricular dysfunction. Angiography showed tight stenosis of the proximal left anterior descending (LAD) and borderline lesion in left circumflex coronary artery (LCX). She underwent percutaneous coronary intervention (PCI) to LAD with good result. Her blood tests showed low vitamin B12, folate and serum iron levels and elevated serum homocysteine level. She was given folic acid and vitamin B12 and her homocysteine levels normalized. This case demonstrates that hyperhomocysteinemia caused by nutritional deficiency of vitamin co factors may lead to MI. Hyperhomocysteinemia should be considered in the evalauation of young people with MI, especially those without conventional risk factors.

What is the influence of hormone therapy on homocysteine and crp levels in postmenopausal women?

OBJECTIVE

To evaluate the influence of estrogen therapy and estrogen-progestin therapy on homocysteine and C-reactive protein levels in postmenopausal women.

METHODS

In total, 99 postmenopausal women were included in this double-blind, randomized clinical trial and divided into three groups: Group A used estrogen therapy alone (2.0 mg of 17β-estradiol), Group B received estrogen-progestin therapy (2.0 mg of 17 β-estradiol +1.0 mg of norethisterone acetate) and Group C received a placebo (control). The length of treatment was six months. Serum measurements of homocysteine and C-reactive protein were carried out prior to the onset of treatment and following six months of therapy.

RESULTS

After six months of treatment, there was a 20.7% reduction in homocysteine levels and a 100.5% increase in C-reactive protein levels in the group of women who used estrogen therapy. With respect to the estrogen-progestin group, there was a 12.2% decrease in homocysteine levels and a 93.5% increase in C-reactive protein levels.

CONCLUSION

Our data suggested that hormone therapy (unopposed estrogen or estrogen associated with progestin) may have a positive influence on decreasing cardiovascular risk due to a significant reduction in homocysteine levels.

The role of homocysteine-lowering B-vitamins in the primary prevention of cardiovascular disease

Cardiovascular disease (CVD) is the leading cause of mortality in the Western world. The effort of research should aim at the primary prevention of CVD. Alongside statin therapy, which is maintained to be an effective method of CVD prevention, there are alternative methods such as vitamin B substitution therapy with folic acid (FA), and vitamins B12 and B6 . B-vitamins may inhibit atherogenesis by decreasing the plasma level of homocysteine (Hcy)-a suspected etiological factor for atherosclerosis-and by other mechanisms, primarily through their antioxidant properties. Although Hcy-lowering vitamin trials have failed to demonstrate beneficial effects of B-vitamins in the prevention of CVD, a meta-analysis and stratification of a number of large vitamin trials have suggested their effectiveness in cardiovascular prevention (CVP) in some aspects. Furthermore, interpretation of the results from these large vitamin trials has been troubled by statin/aspirin therapy, which was applied along with the vitamin substitution, and FA fortification, both of which obscured the separate effects of vitamins in CVP. Recent research results have accentuated a new approach to vitamin therapy for CVP. Studies undertaken with the aim of primary prevention have shown that vitamin B substitution may be effective in the primary prevention of CVD and may also be an option in the secondary prevention of disease if statin therapy is accompanied by serious adverse effects. Further investigations are needed to determine the validity of vitamin substitution therapy before its introduction in the protocol of CVD prevention.

Impact of personalized diet and probiotic supplementation on inflammation, nutritional parameters and intestinal microbiota - The "RISTOMED project": Randomized controlled trial in healthy older people

OBJECTIVES

To assess the impact of a personalized diet, with or without addition of VSL#3 preparation, on biomarkers of inflammation, nutrition, oxidative stress and intestinal microbiota in 62 healthy persons aged 65-85 years.

DESIGN

Open label, randomized, multicenter study.

PRIMARY ENDPOINT

High-sensitivity C-reactive protein.

SETTING

Community.

INTERVENTIONS

Eight week web-based dietary advice (RISTOMED platform) alone or with supplementation of VSL#3 (2 capsules per day). The RISTOMED diet was optimized to reduce inflammation and oxidative stress.

MEASUREMENTS

Blood and stool samples were collected on days 1 and 56.

RESULTS

Diet alone reduced ESR (p = 0.02), plasma levels of cholesterol (p < 0.01) and glucose (p = 0.03). Addition of VSL#3 reduced ESR (p = 0.05) and improved folate (p = 0.007), vitamin B12 (p = 0.001) and homocysteine (p < 0.001) plasma levels. Neither intervention demonstrated any further effects on inflammation. Subgroup analysis showed 40 participants without signs of low-grade inflammation (hsCRP<3 mg/l, subgroup 1) and 21 participants with low-grade inflammation at baseline (hsCRP≥3 mg/l, subgroup 2). In subgroup 2 addition of VSL#3 increased bifidobacteria (p = 0.005) in more participants and improved both folate (p = 0.015) and vitamin B12 (p = 0.035) levels compared with subgroup 1. The increases were positively correlated to the change in the bifidobacteria concentration for folate (p = 0.023) and vitamin B12 (p = 0.001). As expected change in homocysteine correlated negatively to change in folate (r = -0.629, p = 0.002) and vitamin B12 (r = -0.482, p = 0.026).

CONCLUSIONS

Addition of VSL#3 increased bifidobacteria and supported adequate folate and vitamin B12 concentrations in subjects with low-grade inflammation. Decrease in homocysteine with VSL#3 was clinically relevant. suggesting protective potentials for aging-associated conditions, e.g. cardiovascular or neurological diseases. ClinicalTrials.gov: NCT01069445-NCT01179789.

The Effect of Vitamin B12 Infusion on Prevention of Nitrous Oxide-induced Homocysteine Increase: A Double-blind Randomized Controlled Trial

OBJECTIVE

Nitrous oxide is a common inhalation anesthetic agent in general anesthesia. While it is widely accepted as a safe anesthetic agent, evidence suggests exposure to this gas, leads to hyperhomocysteinemia. The present study aimed to evaluate the effects of single-dose intravenous infusions of vitamin B12, before and after the induction of nitrous oxide anesthesia on homocysteine levels after the surgery.

METHODS

This double-blind randomized controlled trial was conducted on 60 patients who were scheduled for elective surgery under general anesthesia, presumably lasting for more than two hours. The subjects were randomly allocated to three groups of 20. For the first group, vitamin B12 solution (1 mg/100 ml normal saline) and 100 ml of normal saline (placebo), were infused before and after the induction of anesthesia, respectively. The second group received placebo and vitamin B12 infusion before and after the induction of anesthesia, respectively. The third group received placebo infusions at both times. Homocysteine levels were measured before and 24 hours after the surgery.

RESULTS

The mean homocysteine and vitamin B12 levels were significantly different within the three groups (p<0.001). In patients who had been infused with vitamin B12 before the surgery, homocysteine levels were significantly lower than the other two groups. In the placebo group, homocysteine levels significantly increased after the surgery.

CONCLUSION

Nitrous oxide causes hyperhomocysteinemia after general anesthesia. Since vitamin B12 infusion is a safe and inexpensive method to decrease homocysteine levels in these patients, it may be recommended for patients undergoing nitrous oxide anesthesia to be used before induction of anesthesia.

Hypermethylation of DDAH2 promoter contributes to the dysfunction of endothelial progenitor cells in coronary artery disease patients

Background

Circulating endothelial progenitor cells (EPCs) may be a biomarker for vascular function and cardiovascular risk in patients with coronary artery disease (CAD). Dimethylarginine dimethylaminohydrolase 2 (DDAH2) regulates the function of EPCs. This study aimed to examine whether hypermethylation of DDAH2 promoter contributes to impaired function of EPCs in CAD patients.

Methods

Peripheral blood mono-nuclear cells from 25 CAD patients and 15 healthy volunteers were collected and differentiated into EPCs. EPCs were tested for their adhesive capability. DDAH2 mRNA expression was analyzed by real-time PCR, and the methylation of DDAH2 promoter was detected by bisulfite genomic sequencing.

Results

DDAH2 promoter in EPCs from CAD patients was hypermethylated and the methylation level was negatively correlated to DDAH2 mRNA level and adhesion function of EPCs. Homocysteine impaired the adhesion function of EPCs, accompanied by lower DDAH2 expression and higher methylation level of DDAH2 promoter, compared to controls. These effects of homocysteine were reversed by pretreatment with Aza, an inhibitor of DNA methyltransferase.

Conclusion

Hypermethylation in DDAH2 promoter is positively correlated to the dysfunction of EPCs in CAD patients. Homocysteine disrupts EPCs function via inducing the hypermethylation of DDAH2 promoter, suggesting a key role of epigenetic mechanism in the progression of atherosclerosis.

Low-dose B vitamins supplementation ameliorates cardiovascular risk: a double-blind randomized controlled trial in healthy Chinese elderly

PURPOSE

We investigated whether daily supplementation with low-dose B vitamins in the healthy elderly population improves the Framingham risk score (FRS), a predictor of cardiovascular disease risk.

METHODS

Between 2007 and 2012, a double-blind randomized controlled trial was conducted in a rural area of North China. In all, 390 healthy participants aged 60-74 were randomly allocated to receive daily vitamin C (50 mg; control group) or vitamin C plus B vitamins (400 µg folic acid, 2 mg B6, and 10 µg B12; treatment group) for 12 months. FRSs were calculated for all 390 subjects.

RESULTS

Folate and vitamin B12 plasma concentrations in the treatment group increased by 253 and 80%, respectively, after 6 months, stopped increasing with continued supplementation after 12 months and returned to baseline levels 6 months after supplementation cessation. Compared with the control group, there was no significant effect of B vitamin supplementation on FRSs after 6 months (mean difference -0.38; 95% CI -1.06, 0.31; p = 0.279), whereas a significant effect of supplementation was evident after 12 months (reduced magnitude 7.6%; -0.77; 95% CI -1.47, -0.06; p = 0.033). However, this reduction disappeared 6 months after supplementation stopped (-0.07; 95% CI -0.80, 0.66; p = 0.855). The reduction in FRS 12 months after supplementation was more pronounced in individuals with a folate deficiency (10.4%; -1.30; 95% CI -2.54, -0.07; p = 0.039) than in those without (4.1%; -0.38; 95% CI -1.12, 0.36; p = 0.313). B vitamins increased high-density lipoprotein cholesterol by 3.4% after 6 months (0.04; 95% CI -0.02, 0.10; p = 0.155) and by 9.2% after 12 months (0.11; 95 % CI 0.04, 0.18; p = 0.003). Compared with the control group, this change in magnitude decreased to 3.3% (0.04; 95 % CI -0.02, 0.10; p = 0.194) 6 months after supplementation cessation.

CONCLUSIONS

Daily supplementation with a low-dose of B vitamins for 12 months reduced FRS, particularly in healthy elderly subjects with a folate deficiency. These reduced effects declined after supplementation cessation, indicating a need for persistent supplementation to maintain the associated benefits.

Endothelial dysfunction in conduit arteries and in microcirculation. Novel therapeutic approaches

The vascular endothelium not only is a single monolayer of cells between the vessel lumen and the intimal wall, but also plays an important role by controlling vascular function and structure mainly via the production of nitric oxide (NO). The so called "cardiovascular risk factors" are associated with endothelial dysfunction, that reduces NO bioavailability, increases oxidative stress, and promotes inflammation contributing therefore to the development of atherosclerosis. The significant role of endothelial dysfunction in the development of atherosclerosis emphasizes the need for efficient therapeutic interventions. During the last years statins, angiotensin-converting enzyme inhibitors, angiotensin-receptor antagonists, antioxidants, beta-blockers and insulin sensitizers have been evaluated for their ability to restore endothelial function (Briasoulis et al., 2012). As there is not a straightforward relationship between therapeutic interventions and improvement of endothelial function but rather a complicated interrelationship between multiple cellular and sub-cellular targets, research has been focused on the understanding of the underlying mechanisms. Moreover, the development of novel diagnostic invasive and non-invasive methods has allowed the early detection of endothelial dysfunction expanding the role of therapeutic interventions and our knowledge. In the current review we present the available data concerning the contribution of endothelial dysfunction to atherogenesis and review the methods that assess endothelial function with a view to understand the multiple targets of therapeutic interventions. Finally we focus on the classic and novel therapeutic approaches aiming to improve endothelial dysfunction and the underlying mechanisms.

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.

Approach to a successful selection of antihypertensive drugs for the patient with atherosclerosis

Coronary heart disease has become a medical and public health issue associated with multiple risk factors such as age, diet, and sedentary life style. Associations between hypertension and atherosclerosis have been extensively studied, and several trials have demonstrated antiatherosclerotic properties in some of the most widely used antihypertensive agents. Hence, calcium channel blockers, angiotensin-converting enzyme inhibitors, and angiotensin receptor blockers have been the target for a number of controlled randomized trials studying its effect on atherosclerosis progression. Carotid intima-media thickness measurement by ultrasound is used as surrogate of atherosclerosis in most of these controlled trials. This review of the literature aims to summarize the most significant controlled trials involving antihypertensive therapy and atherosclerosis regression based on the carotid intima-media thickness measurement.

Plasma homocysteine is associated with aortic arterial stiffness but not wave reflection in Chinese hypertensive subjects

Objective

Elevated plasma total homocysteine (tHcy) acts synergistically with hypertension to exert a multiplicative effect on cardiovascular diseases risk. The aim of this study was to determine the relationship between tHcy concentration and blood pressure, and to evaluate the role of plasma tHcy in arterial stiffness and wave reflection in hypertension.

Methods

In this cross-sectional study, a community-based sample of 1680 subjects (mean age 61.6 years) was classified into four groups according to tHcy level (<21.6 vs. ≥21.6 µmol/l) and blood pressure (hypertensive vs. normotensive). Levels of plasma tHcy and other biochemical parameters (e.g., lipids, glucose) were determined. Central arterial blood pressure, reflected pressure wave, and carotid-femoral pulse wave velocity (cf-PWV) were assessed by tonometry within 2 days of obtaining the blood specimen.

Results

Neither peripheral nor central blood pressure differed according to tHcy levels in normotensive and hypertensive subjects. Differences in cf-PWV according to tHcy were observed only in hypertensive subjects; differences in cf-PWV in normotensive subjects were not significant after adjusting for confounding factors. Central augmentation index did not differ according to tHcy level in either normotensive or hypertensive subjects. Results of univariate analysis revealed significant correlations between blood pressure parameters and tHcy concentration only among normotensive subjects; however, these correlations were not significant in a partial correlation analysis. Results of multiple regression analysis showed that plasma tHcy levels were independently correlated with cf-PWV in hypertensive subjects (β = 0.713, P = 0.004). The independent relationship between tHcy and central augmentation index was not significant by further multiple analyses in normotensive or hypertensive individuals.

Conclusions

Plasma tHcy level is strongly and independently correlated with arterial stiffness measured as cf-PWV only in hypertensive subjects. Thus, hypertension is a major link between tHcy and aortic arterial stiffness.

Vitamin B12 level in peripheral arterial disease

Hyperhomocysteinemia is considered a risk factor for atherosclerosis. Methyltetrahydrofolate reductase (MTHFR) gene mutation and low level of plasma vitamin B12 and folate could take part in the etiology of peripheral arterial disease (PAD). We examined whether plasma vitamin B12 and folate levels and MTHFR-C677T polymorphism are associated with the risk of PAD. The study comprised 293 patients (107 females, 186 males, mean age of 66 ± SEM0.7 years) and 293 sex-matched control subjects (mean age of 62 ± SEM0.8 years). We also determined plasma lipid profile, hs-CRP, creatinine, vitamin B12, folate and total homocysteine (tHcy) for all patients and controls. Odds ratios were non-significant for different genotypes of MTHFR-C677T polymorphism. There was a significant lower level of vitamin B12 in PAD patients. 43 and 25 % of patient and control populations were in the lowest quartile of vitamin B12 (<188 pmol/L), respectively. Plasma level of vitamin B12 in the lowest quartile significantly increased tHcy level in PAD patients, and it was independent of plasma folate level. Low level of plasma vitamin B12 was independently associated with hyperhomocysteinemia in PAD patients. The prevalence of the MTHFR-C677T mutation was not significantly different in patients with PAD compared with controls.

The impact of the lacto-ovo vegetarian diet on the erythrocyte superoxide dismutase activity: a study in the Romanian population

BACKGROUND/OBJECTIVES

Recent studies have shown that vitamin B12 scavenges superoxide anion as effectively as superoxide dismutase (SOD), and has a key role in the defense against oxidative stress. The status of vitamin B12 is suboptimal in a substantial number of vegans and even vegetarians. We therefore evaluated in lacto-ovo vegetarians (LOVs) who did not take vitamin B12 supplements the impact of the duration of this diet on the vitamin B12 status, the erythrocyte SOD activity and the serum malondialdehyde (MDA) concentration.

SUBJECTS/METHODS

The study group included 38 non-vegetarians and 48 LOVs divided, according to the duration of this diet, into two subgroups: LOV1 (2-10 years) and LOV2 (11-29 years). The erythrocyte SOD activity and the serum concentrations of vitamin B12 and MDA were assayed.

RESULTS

In LOVs, the mean serum vitamin B12 concentration, the erythrocyte SOD activity and the mean serum MDA concentration were statistically significantly lower that in non-vegetarians. No significant association between the serum vitamin B12 and MDA concentrations and the duration of the LOV diet were observed. A significant inverse linear correlation between SOD activity and the duration of adherence to LOV diet was observed in LOVs.

CONCLUSIONS

The duration of LOV diet has impact only on SOD activity. Further researches, both in vitro and in vivo, are necessary to understand the underlying molecular mechanism.

Phytoestrogen α-Zearalanol attenuates homocysteine-induced apoptosis in human umbilical vein endothelial cells

Hyperhomocysteinemia is an independent risk factor for cardiovascular diseases. The enhanced nitrative stress plays an important role in homocysteine-induced endothelial dysfunction. Previous studies have showed that phytoestrogen α -zearalanol alleviated endothelial injury in ovariectomized hyperhomocysteinemic rats; however, the underlying mechanism remains to be clarified. This study was to investigate the effects of α -zearalanol on homocysteine-induced endothelial apoptosis in vitro and explore the possible role of nitrative stress in these effects. Results showed that homocysteine (500  μ mol/L, 24 h) induced the apoptosis of human umbilical vein endothelial cells (HUVECs) obviously, and this effect was significantly attenuated by pretreatment with α -zearalanol (10(-8)~10(-6) mol/L). Moreover, α -zearalanol downregulated proapoptotic protein Bax, upregulated antiapoptotic proteins Bcl-2 and Bcl-XL, and decreased the expression and activity of caspase-9. These findings demonstrated that α -zearalanol could effectively alleviate homocysteine-induced endothelial apoptosis, and this antiapoptosis effect might be related to the inhibition of the intrinsic pathway. Western blot indicated an enhanced 3-nitrotyrosine expression in HUVECs when challenged with homocysteine, which was attenuated by pretreatment with α -zearalanol. This result implied that inhibition of nitrative stress might play a role in the protective effect of α -zearalanol on endothelial cells. Such discovery may shed a novel light on the antiatherogenic activities of α -zearalanol in hyperhomocysteinemia.

Association between low-dose folic acid supplementation and blood lipids concentrations in male and female subjects with atherosclerosis risk factors

Background

Folic acid (FA) is one of the B complex vitamins. It is thought that FA deficiency promotes atherosclerosis formation in arterial endothelium. FA, acting through reducing homocysteine (Hcy) levels, may contribute to decreased cholesterol (Ch) synthesis.

The aim of this study was to analyze the association of low-dose folic acid supplementation with blood lipids concentrations in subjects with atherosclerosis risk factors.

Material/Methods

The study enrolled 124 Caucasian individuals (60 M, ages 20–39; and 64 F, ages 19–39) with atherosclerosis risk factors (family history of premature ischemic stroke, arterial hypertension, dyslipidemia, overweight and obesity, cigarette smoking, and low level of physical activity). The participants were asked to take FA at a low dose of 0.4 mg/24 h for 12 weeks.

Results

FA levels increased in females (6.3 vs. 12.5 ng/dL; p=0.001) and males (6.4 vs. 11.4 ng/dL; p=0.001) and Hcy levels decreased (10.6 vs. 8.3 μmol/L; p=0.001 and 11.5 vs. 9.3; p=0.001, respectively). A significant reduction in mean concentration of total cholesterol in females (203.4 vs. 193.1 mg/dL; p=0.001) and in males (209.5 vs. 201.9; p=0.002) was observed. The low-density lipoprotein cholesterol (LDL-C) levels decreased in females and in males (107.4 vs. 99.9 mg/dL; p=0.001 and 121.5 vs. 115.1; p=0.002, respectively). The apoAI concentrations increased in smoking women and in men with BMI ≥25 kg/m² (p=0.032 and p=0.024, respectively).

Conclusions

Low-dose FA supplementation has a beneficial effect on blood lipids through decreasing concentrations of total cholesterol and LDL-C and increasing concentrations of apoAI.

Effect of folic acid supplementation on levels of circulating Monocyte Chemoattractant Protein-1 and the presence of intravascular ultrasound derived virtual histology thin-cap fibroatheromas in patients with stable angina pectoris

BACKGROUND

Virtual Histology Intravascular Ultrasound (VH-IVUS) may be used to detect early signs of unstable coronary artery disease. Monocyte Chemoattractant Protein-1 (MCP-1) is linked with coronary atherosclerosis and plaque instability and could potentially be modified by folic acid treatment.

METHODS

In a randomized, prospective study, 102 patients with stable angina pectoris (SAP) received percutaneous coronary intervention and established medical treatment as well as either homocysteine-lowering folic acid/vitamin B12 (± B6) or placebo (± B6) for 1 year before VH-IVUS was performed. The presence of VH-Thin-Cap Fibroatheroma (VH-TCFA) in non-intervened coronary vessels was registered and serum levels of MCP-1 were measured. The patients were subsequently followed for incident myocardial infarction (MI).

RESULTS

Patients treated with folic acid/vitamin B12 had a geometric mean (SD) MCP-1 level of 79.95 (1.49) versus 86.00 (1.43) pg/mL for patients receiving placebo (p-value 0.34). VH-TCFA lesions were present in 7.8% of patients and did not differ between intervention arms (p-value 0.47). Serum levels of MCP-1 were 1.46 (95% CI 1.12 to 1.92) times higher in patients with VH-TCFA lesions than in those without (p-value 0.005). Afterwards, patients were followed for median 2.1 years and 3.8% experienced a myocardial infarction (MI), which in post-hoc Cox regression analyses was independently predicted by both MCP-1 (P-value 0.006) and VH-TCFA (p-value 0.01).

CONCLUSIONS

In patients with SAP receiving established medical treatment, folic acid supplementation is not associated with either presence of VH-TCFA or levels of MCP-1. MCP-1 is however associated with VH-TCFA, a finding corroborated by increased risk for future MI. ClinicalTrials.gov Identifier: NCT00354081.