Mechanisms of cardiovascular remodeling in hyperhomocysteinemia

Homocysteine contributes to atherogenic transformation of the aorta in rabbits in the absence of hypercholesterolemia

Atherosclerosis, the leading cause of cardiovascular disease, cannot be sufficiently explained by established risk factors, including cholesterol. Elevated plasma homocysteine (Hcy) is an independent risk factor for atherosclerosis and is closely linked to cardiovascular mortality. However, its role in atherosclerosis has not been fully clarified yet. We have previously shown that rabbits fed a diet deficient in B vitamins and choline (VCDD), which are required for Hcy degradation, exhibit an accumulation of macrophages and lipids in the aorta, aortic stiffening and disorganization of aortic collagen in the absence of hypercholesterolemia, and an aggravation of atherosclerosis in its presence. In the current study, plasma Hcy levels were increased by intravenous injections of Hcy into balloon-injured rabbits fed VCDD (VCDD+Hcy) in the absence of hypercholesterolemia. While this treatment did not lead to thickening of aortic wall, intravenous injections of Hcy into rabbits fed VCDD led to massive accumulation of VLDL-triglycerides as well as significant impairment of vascular reactivity of the aorta compared to VCDD alone. In the aorta intravenous Hcy injections into VCDD-fed rabbits led to fragmentation of aortic elastin, accumulation of elastin-specific electron-dense inclusions, collagen disorganization, lipid degradation, and autophagolysosome formation. Furthermore, rabbits from the VCDD+Hcy group exhibited a massive decrease of total protein methylated arginine in blood cells and decreased creatine in blood cells, serum and liver compared to rabbits from the VCDD group. Altogether, we conclude that Hcy contributes to atherogenic transformation of the aorta not only in the presence but also in the absence of hypercholesterolemia.

Nicotinamide N-Methyltransferase (NNMT): A New Hope for Treating Aging and Age-Related Conditions

The complex process of aging leads to a gradual deterioration in the function of cells, tissues, and the entire organism, thereby increasing the risk of disease and death. Nicotinamide N-methyltransferase (NNMT) has attracted attention as a potential target for combating aging and its related pathologies. Studies have shown that NNMT activity increases over time, which is closely associated with the onset and progression of age-related diseases. NNMT uses S-adenosylmethionine (SAM) as a methyl donor to facilitate the methylation of nicotinamide (NAM), converting NAM into S-adenosyl-L-homocysteine (SAH) and methylnicotinamide (MNA). This enzymatic action depletes NAM, a precursor of nicotinamide adenine dinucleotide (NAD+), and generates SAH, a precursor of homocysteine (Hcy). The reduction in the NAD+ levels and the increase in the Hcy levels are considered important factors in the aging process and age-related diseases. The efficacy of RNA interference (RNAi) therapies and small-molecule inhibitors targeting NNMT demonstrates the potential of NNMT as a therapeutic target. Despite these advances, the exact mechanisms by which NNMT influences aging and age-related diseases remain unclear, and there is a lack of clinical trials involving NNMT inhibitors and RNAi drugs. Therefore, more in-depth research is needed to elucidate the precise functions of NNMT in aging and promote the development of targeted pharmaceutical interventions. This paper aims to explore the specific role of NNMT in aging, and to evaluate its potential as a therapeutic target.

Is There a Connection between Hyperhomocysteinemia and the Cardiometabolic Syndrome?

This study investigates the distribution of hyperhomocysteinemia and cardiovascular metabolic syndrome (SM) among participants, shedding light on their prevalence and co-occurrence within the study cohort. Through an analysis of demographic characteristics and health parameters, including age, gender, and body mass index (BMI), alongside nutritional data, correlations between these factors and health risks are explored. Results reveal a notable prevalence of hyperhomocysteinemia, with 45.3% of participants exhibiting this condition. Furthermore, 31.4% of the cohort does not present hyperhomocysteinemia or SM, while 23.3% shows SM without hyperhomocysteinemia. The study underscores gender-specific dietary recommendations due to significant variations in nutrient intake patterns. Additionally, inverse correlations between health risks like obesity, hypertension, and hypercholesterolemia and nutrient requirements highlight the need for tailored dietary interventions. Age-related changes in nutrient needs and the positive correlation between physical activity levels and certain nutrient demands further emphasize the importance of personalized dietary strategies. Variations in nutrient intake by gender, inverse correlations with health risks, and age-related changes underscore the need for tailored dietary strategies. These findings provide valuable insights for healthcare professionals in developing targeted nutritional interventions to mitigate disease risk and promote overall health and well-being.

Infection with Helicobacter pylori may predispose to atherosclerosis: role of inflammation and thickening of intima-media of carotid arteries

Atherosclerosis is a major instigator of cardiovascular disease (CVD) and a main cause of global morbidity and mortality. The high prevalence of CVD calls for urgent attention to possible preventive measures in order to curb its incidence. Traditional risk factors of atherosclerosis, like age, smoking, diabetes mellitus, dyslipidemia, hypertension and chronic inflammation, are under extensive investigation. However, these only account for around 50% of the etiology of atherosclerosis, mandating a search for different or overlooked risk factors. In this regard, chronic infections, by Helicobacter pylori for instance, are a primary candidate. H. pylori colonizes the gut and contributes to several gastrointestinal diseases, but, recently, the potential involvement of this bacterium in extra-gastric diseases including CVD has been under the spotlight. Indeed, H. pylori infection appears to stimulate foam cell formation as well as chronic immune responses that could upregulate key inflammatory mediators including cytokines, C-reactive protein, and lipoproteins. These factors are involved in the thickening of intima-media of carotid arteries (CIMT), a hallmark of atherosclerosis. Interestingly, H. pylori infection was found to increase (CIMT), which along with other evidence, could implicate H. pylori in the pathogenesis of atherosclerosis. Nevertheless, the involvement of H. pylori in CVD and atherosclerosis remains controversial as several studies report no connection between H. pylori and atherosclerosis. This review examines and critically discusses the evidence that argues for a potential role of this bacterium in atherogenesis. However, additional basic and clinical research studies are warranted to convincingly establish the association between H. pylori and atherosclerosis.

Application of homocysteine as a non-invasive and effort-free measurements for risk assessment of patients with pulmonary hypertension

BACKGROUND

Current guideline-recommended multiparameters used to assess the risk levels of pulmonary arterial hypertension (PAH) are invasive hemodynamic measurements or effort-dependent exercise tests. Serum natriuretic peptide is only one kind of effort-free biomarker that has been adopted for risk assessment. This study aimed to investigate the application of homocysteine as a non-invasive and effort-free measurement for the risk assessment of patients with PAH.

METHODS

Samples of 50 patients diagnosed with PAH via right heart catheterization were obtained, and the patients were divided into low-, intermediate- and high-risk groups for further analysis. Additionally, serum N-terminal prohormone of B-type natriuretic peptide (NT-proBNP) and homocysteine levels of monocrotaline (MCT)-induced PAH rats were analyzed at each week with progressed severity of PAH, and they were sacrificed on day 28 with pathology being assessed.

RESULTS

Hyperhomocysteinemia was an independent predictor (odds ratio [OR]: 1.256; 95% confidence interval [CI]: 1.002-1.574) and showed a linear correlation with NT-proBNP. Hyperhomocysteinemia could discriminate between low/intermediate and high-risk levels in PAH with a cut-off value in 12 μmol/L. Moreover, the elevated homocysteine levels by weeks in MCT rats also demonstrated the association between homocysteine and the severity of PAH.

CONCLUSIONS

Homocysteine can be a non-invasive and effort-free risk assessment for patients with pulmonary hypertension. Homocysteine level had a linear correlation with NT-proBNP level, and patients with hyperhomocysteinemia had a higher risk level, higher NT-proBNP level, and decreased lower diffusing capacity for carbon monoxide. The correlation between homocysteine level and PAH severity was also demonstrated in MCT rats.

Plasma homocysteine levels and associated factors in community-dwelling adolescents: the EVA-TYROL study

Background

Homocysteine (Hcy) has been associated with an adverse cardiovascular risk profile in adolescents. Assessment of the association between plasma Hcy levels and clinical/laboratory factors might improve our understanding of the pathogenesis of cardiovascular disease.

Methods

Hcy was measured in 1,900 14- to 19-year-old participants of prospective population-based EVA-TYROL Study (44.3% males, mean age 16.4 years) between 2015 and 2018. Factors associated with Hcy were assessed by physical examination, standardized interviews, and fasting blood analysis.

Results

Mean plasma Hcy was 11.3 ± 4.5 µmol/L. Distribution of Hcy was characterized by extreme right skew. Males exhibited higher Hcy and sex differences increased with increasing age. Univariate associations with Hcy emerged for age, sex, body mass index, high-density lipoprotein cholesterol, and for factors pertaining to blood pressure, glucose metabolism, renal function, and diet quality, whereas the most important multivariate predictors of Hcy were sex and creatinine.

Discussion

Clinical and laboratory factors associated with Hcy in adolescents were manifold, with sex and high creatinine identified as strongest independent determinants. These results may aid when interpreting future studies investigating the vascular risk of homocysteine.

Integrating transcriptomics and metabolomics to analyze the mechanism of hypertension-induced hippocampal injury

Objective

Hypertension is a public health challenge worldwide due to its high prevalence and multiple complications. Hypertension-induced damage to the hippocampus leads to behavioral changes and various brain diseases. Despite the multifaceted effects of hypertension on the hippocampus, the mechanisms underlying hippocampal lesions are still unclear.

Methods

The 32-week-old spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats were selected as the study subjects. Behavioral experiments such as an open field test (OFT), an elevated plus maze (EPM) test, and the Morris water maze (MWM) test were performed to show the behavioral characteristics of the rats. A comprehensive transcriptomic and metabolomic analysis was performed to understand the changes in the hippocampus at the metabolic and genetic levels.

Results

Behavioral tests showed that, compared to WKY rats, SHR showed not only reduced memory capacity but more hyperactive and impulsive behavior. In addition, transcriptomic analysis screened for 103 differentially expressed genes. Metabolomic analysis screened 56 metabolites with significant differences, including various amino acids and their related metabolites.

Conclusion

Comprehensive analysis showed that hypertension-induced hippocampal lesions are closely associated with differential metabolites and differential genes detected in this study. The results provide a basis for analyzing the mechanisms of hypertension-induced hippocampal damage.

The relationship between hyperhomocysteinemia and total coronary artery occlusion: a cross-sectional study from Southwest China

BACKGROUND

Increasing evidence points to hyperhomocysteinemia as an independent risk factor for coronary artery disease in addition to traditional cardiovascular risks, but few have studied the association between hyperhomocysteinemia and total coronary artery occlusion (TCAO). To understand the risk factors for TCAO, we investigated the potential relationship between hyperhomocysteinemia and TCAO, and the interactions between cardiovascular risk factors and hyperhomocysteinemia.

METHODS

A total of 890 adult patients from Southwest China participated in this cross-sectional study between February 2018 and February 2021. TCAO was defined as complete occlusion of more than one of the 15 coronary segments. Hyperhomocysteinemia was defined as serum homocysteine levels ≥15 μmol/L. Multivariable logistic regression models were used to determine the relationship between hyperhomocysteinemia and TCAO. The relationship between homocysteine as a continuous variable and TCAO was also analyzed. Subgroup analyses by sex, age, weight, smoking, hypertension, diabetes, and dyslipidemia were done, and interactions between subgroup variables and hyperhomocysteinemia were performed.

RESULTS

Individuals with hyperhomocysteinemia showed an increased risk for TCAO. The adjusted odds ratio for TCAO in individuals with hyperhomocysteinemia was 1.74 (95% confidence interval, 1.28-2.36). When analyzed as a continuous variable, homocysteine was associated with an increased risk for TCAO. Subgroup analysis showed that the association between hyperhomocysteinemia and TCAO was statistically significant in men, elderly, overweight, smokers, and non-diabetic people. Interaction analysis showed no significant interactions between hyperhomocysteinemia and group variables.

CONCLUSIONS

In Southwest China, hyperhomocysteinemia was significantly associated with TCAO. This association was particularly significant in men, elderly, overweight, smokers, and non-diabetic people.

MTHFR c.665C>T and c.1298A>C Polymorphisms in Tailoring Personalized Anti-TNF-α Therapy for Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an inflammatory autoimmune disease with a prevalence of 1%. Currently, RA treatment aims to achieve low disease activity or remission. Failure to achieve this goal causes disease progression with a poor prognosis. When treatment with first-line drugs fails, treatment with tumor necrosis factor-α (TNF-α) inhibitors may be prescribed to which many patients do not respond adequately, making the identification of response markers urgent. This study investigated the association of two RA-related genetic polymorphisms, c.665C>T (historically referred to as C677T) and c.1298A>C, in the MTHFR gene as response markers to an anti-TNF-α therapy. A total of 81 patients were enrolled, 60% of whom responded to the therapy. Analyses showed that both polymorphisms were associated with a response to therapy in an allele dose-dependent manner. The association for c.665C>T was significant for a rare genotype (p = 0.01). However, the observed opposite trend of association for c.1298A>C was not significant. An analysis revealed that c.1298A>C, unlike c.665C>T, was also significantly associated with the drug type (p = 0.032). Our preliminary results showed that the genetic polymorphisms in the MTHFR gene were associated with a response to anti-TNF-α therapy, with a potential significance for the anti-TNF-α drug type. This evidence suggests a role for one-carbon metabolism in anti-TNF-α drug efficacy and contributes to further personalized RA interventions.

Sulfide regulation of cardiovascular function in health and disease

Hydrogen sulfide (H2S) has emerged as a gaseous signalling molecule with crucial implications for cardiovascular health. H2S is involved in many biological functions, including interactions with nitric oxide, activation of molecular signalling cascades, post-translational modifications and redox regulation. Various preclinical and clinical studies have shown that H2S and its synthesizing enzymes - cystathionine γ-lyase, cystathionine β-synthase and 3-mercaptosulfotransferase - can protect against cardiovascular pathologies, including arrhythmias, atherosclerosis, heart failure, myocardial infarction and ischaemia-reperfusion injury. The bioavailability of H2S and its metabolites, such as hydropersulfides and polysulfides, is substantially reduced in cardiovascular disease and has been associated with single-nucleotide polymorphisms in H2S synthesis enzymes. In this Review, we highlight the role of H2S, its synthesizing enzymes and metabolites, their roles in the cardiovascular system, and their involvement in cardiovascular disease and associated pathologies. We also discuss the latest clinical findings from the field and outline areas for future study.

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

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

Circulating homocysteine and folate concentrations and risk of type 2 diabetes: A retrospective observational study in Chinese adults and a Mendelian randomization analysis

Background

The relation between circulating homocysteine (hcy) and folate concentrations and risk of type 2 diabetes mellitus (T2DM) has been evaluated in several observational studies with inconsistent results; and it is unclear about their causal relationships. Our aim was to assess the causality association between circulating hcy or folate concentrations and the development of T2DM using Mendelian randomization (MR) analysis, based on results of an observational study in Chinese adults.

Methods

We conducted an observational study of 370 patients with T2DM and 402 controls after routine physical examination who consulted at the Zhongnan Hospital of Wuhan University between March 2021 and December 2021. Correlations between hcy and folate and the incidence of T2DM were quantified using logistic regression models. Two-sample MR analysis was conducted using summary statistics of genetic variants gained from 2 genome-wide association studies (GWAS) on circulating hcy and folate concentrations in individuals of European ancestry and from an independent GWAS study based on DIAMANTE meta-analysis.

Results

In the observational study, after logistic regression with multiple adjustment, lower hcy and higher folate levels were identified to be associated with the risk of T2DM, with OR (95% CI) for hcy of 1.032 (1.003–1.060); while 0.909 (0.840–0.983) for folate. In the MR analysis, the OR for T2DM was 1.08 (95% CI: 0.95, 1.21; P = 0.249) for each SD unit increase in genetically predicted homocysteinemia and the OR for T2DM per SD increase in genetically predicted folate elevation was 0.80 (95% CI: 0.60, 1.00, P = 0.026).

Conclusions

We discovered that high circulating hcy and low folate concentrations were related with an increased risk of developing T2DM in Chinese adults. Moreover, MR analysis provided genetic evidence for a possible causal relationship between serum folate and the risk of T2DM.

The Role of Amino Acids in Endothelial Biology and Function

The vascular endothelium acts as an important component of the vascular system. It is a barrier between the blood and vessel wall. It plays an important role in regulating blood vessel tone, permeability, angiogenesis, and platelet functions. Several studies have shown that amino acids (AA) are key regulators in maintaining vascular homeostasis by modulating endothelial cell (EC) proliferation, migration, survival, and function. This review summarizes the metabolic and signaling pathways of AAs in ECs and discusses the importance of AA homeostasis in the functioning of ECs and vascular homeostasis. It also discusses the challenges in understanding the role of AA in the development of cardiovascular pathophysiology and possible directions for future research.

The Potential of Dietary Bioactive Compounds against SARS-CoV-2 and COVID-19-Induced Endothelial Dysfunction

COVID-19 is an endothelial disease. All the major comorbidities that increase the risk for severe SARS-CoV-2 infection and severe COVID-19 including old age, obesity, diabetes, hypertension, respiratory disease, compromised immune system, coronary artery disease or heart failure are associated with dysfunctional endothelium. Genetics and environmental factors (epigenetics) are major risk factors for endothelial dysfunction. Individuals with metabolic syndrome are at increased risk for severe SARS-CoV-2 infection and poor COVID-19 outcomes and higher risk of mortality. Old age is a non-modifiable risk factor. All other risk factors are modifiable. This review also identifies dietary risk factors for endothelial dysfunction. Potential dietary preventions that address endothelial dysfunction and its sequelae may have an important role in preventing SARS-CoV-2 infection severity and are key factors for future research to address. This review presents some dietary bioactives with demonstrated efficacy against dysfunctional endothelial cells. This review also covers dietary bioactives with efficacy against SARS-CoV-2 infection. Dietary bioactive compounds that prevent endothelial dysfunction and its sequelae, especially in the gastrointestinal tract, will result in more effective prevention of SARS-CoV-2 variant infection severity and are key factors for future food research to address.

The Biological Role of Vitamins in Athletes’ Muscle, Heart and Microbiota

Physical activity, combined with adequate nutrition, is considered a protective factor against cardiovascular disease, musculoskeletal disorders, and intestinal dysbiosis. Achieving optimal performance requires a significantly high energy expenditure, which must be correctly supplied to avoid the occurrence of diseases such as muscle injuries, oxidative stress, and heart pathologies, and a decrease in physical performance during competition. Moreover, in sports activities, the replenishment of water, vitamins, and minerals consumed during training is essential for safeguarding athletes’ health. In this scenario, vitamins play a pivotal role in numerous metabolic reactions and some muscle biochemical adaptation processes induced by sports activity. Vitamins are introduced to the diet because the human body is unable to produce these micronutrients. The aim of this review is to highlight the fundamental role of vitamin supplementation in physical activity. Above all, we focus on the roles of vitamins A, B6, D, E, and K in the prevention and treatment of cardiovascular disorders, muscle injuries, and regulation of the microbiome.

Combined Effect of Homocysteine and Uric Acid to Identify Patients With High Risk for Subclinical Atrial Fibrillation

Background

Subclinical atrial fibrillation (SCAF) is often asymptomatic nonetheless harmful. In patients with cardiac implantable electronic devices, we evaluated the combined performance of homocysteine and uric acid (UA) biomarkers to discriminate high‐risk patients for SCAF.

Methods and Results

We enrolled 1224 consecutive patients for evaluation of SCAF in patients with cardiac implantable electronic devices in Dalian, China, between January 2013 and December 2019. Clinical data and blood samples were obtained from patients selected according to the absence or presence of atrial high‐rate episodes >6 minutes. Blood samples were obtained, and homocysteine and UA biomarkers were tested in all patients to distinguish their prognostic performance for SCAF. Homocysteine and UA biomarkers were significantly different in SCAF versus no SCAF. On multivariable Cox regression analysis with potential confounders, elevated homocysteine and UA biomarkers were significantly associated with an increased risk of SCAF. A rise of 1 SD in homocysteine (5.7 μmol/L) was associated with an increased risk of SCAF in men and women regardless of their UA levels. Similarly, a 1‐SD increase in UA (91 μmol/L) was associated with an increased risk of SCAF among the patients with high levels of homocysteine in men (hazard ratio, 1.81; 95% CI, 1.43–2.30) and women (hazard ratio, 2.11; 95% CI, 1.69–2.62). The addition of homocysteine and UA to the atrial fibrillation risk factors recommended by the 2020 European Society of Cardiology Guidelines significantly improved risk discrimination for SCAF.

Conclusions

Homocysteine and UA biomarkers were strongly associated with SCAF. The prediction performance of the European Society of Cardiology model for SCAF was increased by the addition of the selected biomarkers.

Registration

URL: https://www.chictr.org.cn; Unique identifier: Chi‐CTR200003837.

Correlation among cystatin C, homocysteine and arteriosclerosis indexes in patients with chronic kidney disease

OBJECTIVES

Chronic kidney disease (CKD) has become an important public health problem in the world. The occurrence of cardiovascular events is the main cause of death in patients with CKD, and arteriosclerosis is an important pathophysiological basis for cardiovascular diseases. Nowadays, brachial-ankle pulse wave velocity (baPWV) and ankle-brachial index (ABI) are clinically important indicators to reflect early atherosclerosis. Cystatin C (Cys C)and homocysteine (Hcy) are related to arteriosclerosis in healthy, hypertensive, and diabetic people, while there are few studies on the correlation among Hcy, CysC and arteriosclerosis in patients with CKD. This study aims to investigate the relationship between Cys C, Hcy and atherosclerosis in patients with CKD.

METHODS

A total of 611 individuals, who met the diagnostic criteria for CKD and underwent physical examination in the Health Management Center of Third Xiangya Hospital, Central South University from June 2019 to June 2020, were selected as the research subjects. Height, weight, systolic blood pressure (SBP), and diastolic blood pressure (DBP) were measured and recorded, and body mass index (BMI) was calculated. Blood samples (5 mL) were collected and Cys C, Hcy, fasting blood glucose (FBG), total cholesterol (TC), serum creatinine (SCr), and other blood indexes were tested. Urine was collected to detect microalbumin and creatinine, and the albumin/creatinine ratio (UACR) was calculated. baPWV and ABI were measured by automatic arteriosclerosis detector. The quartiles of Cys C and Hcy were divided into groups, and the proportion of baPWV and ABI abnormalities among groups was compared pairwise. The correlation between Cys C, Hcy, and baPWV was analyzed by Pearson correlation analysis. Univariate and multivariate logistic regression were used to analyze the effects of Cys C and Hcy on ABI and baPWV.

RESULTS

Among 611 patients with CKD, 435 (71.19%) had abnormal baPWV and 48 (7.86%) had abnormal ABI. With the increase of Cys C and Hcy levels, the proportion of baPWV and ABI abnormalities were gradually increased. BaPWV was positively correlated with Cys C (r=0.32) and Hcy (r=0.20). After adjusting for confounding factors such as gender, BMI, and FBG, Cys C (OR=6.54, 95% CI 1.93 to 22.14, P<0.01) and Hcy (OR=1.08, 95% CI 1.01 to 1.16, P=0.02) were independent risk factors for abnormal baPWV. Also, after adjusting for confounding factors such as age, sex, BMI, and FBG, Cys C (OR=9.95, 95% CI 2.84 to 34.92, P<0.01) and Hcy (OR=1.06, 95% CI 1.01 to 1.11, P=0.02) were independent risk factors for abnormal ABI.

CONCLUSIONS

In patients with CKD, baPWV and ABI are significantly correlated with Cys C and Hcy levels. Detection of Cys C and Hcy levels is helpful for the early diagnosis of arteriosclerosis.

Synergistic association of hyperuricemia and hyperhomocysteinemia with chronic kidney disease in middle-aged adults and the elderly population

Chronic kidney disease (CKD) is a major global public health issue. Both hyperhomocysteinemia (HHcy) and hyperuricemia are independent risk factors for CKD. In this study, we evaluated the association of HHcy and hyperuricemia with CKD in the middle-aged and elderly populations in Taiwan.In this cross-sectional study, we collected the data of 5910 patients aged ≥50 years after their self-paid health examination at a single medical center. Homocysteine (Hcy) levels were divided into 4 quartiles (Q1, <8.2; Q2, 8.2-9.8; Q3, 9.9-11.7; and Q4, >11.7 μM/L). Renal function was determined using the Chronic Kidney Disease Epidemiology Collaboration equation. Patients were considered to have CKD if their estimated glomerular filtration rate was < 60 mL/min/1.73 m2.The prevalence of CKD significantly increased with the quartiles of uric acid (UA) and Hcy. In multiple logistic regression analysis, the odds ratios (ORs) of CKD increased with the quartiles of Hcy, independent of UA. There was 22.9 in Q4 in the normal serum UA group and 18.3 in the hyperuricemia group compared with Q1 of Hcy. Both hyperuricemia (OR 2.9) and Q4 of Hcy (OR 8.1) were significant independent risk factors for CKD. Furthermore, hyperuricemia and HHcy had significant synergistic association (synergy index, 1.7) with CKD.The ORs of CKD increased with the quartiles of Hcy, independent of hyperuricemia. Hyperuricemia and HHcy had synergistic association with CKD.

Value of neutrophil-to-lymphocyte ratio as a marker of renal damage in patients with H-type hypertension

Aim: To explore the relationship between the neutrophil-to-lymphocyte ratio (NLR) and renal damage in patients with H-type hypertension. Materials & methods: A total of 618 patients between 2017 and 2019 were analyzed retrospectively. Results: NLR was significantly correlated with renal damage in hypertension patients. Appropriate cut-off value for NLR (2.247) was determined by receiver operating characteristic curve; linear regression analysis showed that NLR and estimated glomerular filtration rate, blood urea nitrogen/creatinine has a significant negative correlation in H-type hypertension group (p < 0.05); logistic regression analysis showed that the risk of renal damage increased by 10% for each 1 umol/l increase of homocysteine, and 51% for each 1.0 increase of NLR in H-type hypertension patients. Conclusion: NLR worth popularizing in prediction of renal damage in patients with H-type hypertension.

Current progress on the mechanisms of hyperhomocysteinemia-induced vascular injury and use of natural polyphenol compounds

Cardiovascular disease is one of the most common diseases in the elderly population, and its incidence has rapidly increased with the prolongation of life expectancy. Hyperhomocysteinemia is an independent risk factor for various cardiovascular diseases, including atherosclerosis, and damage to vascular function plays an initial role in its pathogenesis. This review presents the latest knowledge on the mechanisms of vascular injury caused by hyperhomocysteinemia, including oxidative stress, endoplasmic reticulum stress, protein N-homocysteinization, and epigenetic modification, and discusses the therapeutic targets of natural polyphenols. Studies have shown that natural polyphenols in plants can reduce homocysteine levels and regulate DNA methylation by acting on oxidative stress and endoplasmic reticulum stress-related signaling pathways, thus improving hyperhomocysteinemia-induced vascular injury. Natural polyphenols obtained via daily diet are safer and have more practical significance in the prevention and treatment of chronic diseases than traditional drugs.

Effect of Vitamin D Status on Vascular Function of the Aorta in a Rat Model of PCOS

Polycystic ovary syndrome (PCOS) is associated with elevated cardiovascular risk. Early vascular dysfunction may lead to the development of cardiovascular disease in PCOS. Vitamin D deficiency (VDD) is a common comorbidity of PCOS that contributes to the pathogenesis of the disease and its complications. Both PCOS and VDD are accompanied by increased oxidative stress that may be involved in the arising vascular dysfunction. We aimed to investigate the role of vitamin D status on aortic function. PCOS was induced by an 8-week-long transdermal testosterone treatment of female rats, and low and adequate vitamin D status was achieved by dietary means. Contraction and relaxation abilities of isolated aortic segments were measured by myograph. Resorcin-fuchsin staining and immunohistochemical labeling of 3-nitrotyrosine were performed. No difference was shown in the norepinephrine-induced contraction of the aortas of different groups, whereas we detected reduced acetylcholine- and insulin-evoked relaxation in VDD groups. A lower level of resorcin-fuchsin staining and elevated 3-nitrotyrosine immunostaining was observed in VDD. In our study, we demonstrated early endothelial dysfunction in VDD PCOS rat model. Vitamin D supplementation could prevent vascular disturbances, while VDD itself damaged endothelium-dependent vasorelaxation and induced nitrative stress.

Hyperhomocysteinemia-induced Nrf2/HO-1 pathway suppression aggravates cardiac remodeling of hypertensive rats

ABJECTIVE

Interaction of hypertension and hyperhomocysteinemia (HHcy) leads to enhanced cardiac remodeling in hypertensive heart disease. However, the mechanism of collagen accumulation and cardiac remodeling remains unclear. In this study, we attempted to evaluate the relationship between hypertension and HHcy in the context of cardiac remodeling and to explore its mechanism of action.

METHODS

Wistar Kyoto (WKY) and spontaneous hypertension rats (SHR) were randomly divided into four groups, namely WKY group, WKY + HHcy group, SHR group and SHR + HHcy group. We measured blood pressure (BP), plasma homocysteine (Hcy), serum superoxide dismutase (SOD) and serum malondialdehyde (MDA). We also examined cardiac histopathology and gene and protein expression levels of Nrf2 and HO-1.

RESULTS

Compared with the WKY group, myocardial interstitial and perivascular collagen deposition in the WKY + HHcy group, the SHR group and the SHR + HHcy group increased successively, indicating that cardiac remodeling gradually increased, and HHcy aggravated cardiac remodeling was more serious in hypertensive rats. SOD decreased gradually in the four groups, while MDA was on the contrary. WKY + HHcy and SHR + HHcy groups both suppressed Nrf2 and HO-1 expression and inhibited the translocation of Nrf2 from cytoplasm to nucleus compared with their control groups, and the SHR + HHcy group had a stronger inhibitory effect.

CONCLUSION

HHcy enhanced cardiac remodeling in rats by enhancing oxidative stress, suppressing the Nrf2/HO-1 pathway and Nrf2 nuclear transport, and this inhibitory effect was stronger in the context of hypertension.

Distribution Pattern of Atherosclerosis in the Abdomen and Lower Extremities and Its Association with Clinical and Hematological Factors

PURPOSE

Abdominal arteries differ from the arteries located at the extremities in histological composition and clinical features. This study investigated the distributional pattern of atherosclerosis in arteries of the abdomen and lower extremities and its association with clinical and hematologic factors.

PATIENTS AND METHODS

This retrospective study included 227 patients with atherosclerosis who underwent computed tomography angiography (CTA) of the abdomen and lower extremities. The distributional pattern of atherosclerosis was categorized into type 1 (suprainguinal elastic), type 2 (infrainguinal muscular), and type 3 (both arterial involvement). Chi-square tests, Mann-Whitney U-tests, and logistic regression analysis were used to investigate the data.

RESULTS

Of the 227 patients, 132 (58%) had type 1 and 95 (42%) had type 3 atherosclerosis. None had type 2. Older age, heavier smoking, and higher levels of HbA1c and homocysteine were the significant risk factors for type 3 atherosclerosis (odds ratio: 1.076, 1.023, 1.426, and 1.130, respectively). Patients with type 3 showed significantly lower right and left ankle and toe brachial indices compared to type 1 (P: 0.029, 0.023, 0.003, and <0.001, respectively).

CONCLUSION

In arteries of the abdomen and lower extremities, atherosclerosis may occur initially at suprainguinal elastic arteries. In addition, the significant risk factors for type 3 atherosclerosis may contribute to the development of atherosclerosis at infrainguinal muscular arteries and deteriorate the peripheral arterial circulation. Therefore, if atherosclerotic lesions are found at the suprainguinal elastic arteries on CTA, to prevent atherosclerosis at infrainguinal muscular arteries and subsequent peripheral arterial ischemic disease, cessation of smoking and control of blood glucose and homocysteine may be recommended, especially in elderly patients.

Association of Severity and Prognosis With Elevated Homocysteine Levels in Patients With Intracerebral Hemorrhage

Background: Intracerebral hemorrhage (ICH) has high mortality and morbidity rates in the world. Homocysteine (Hcy) has been demonstrated to be an independent risk factor and could predict the prognosis and recurrence of ischemic stroke. In our study, we aimed to find out the relationship between Hcy levels and the severity and prognosis of patients with ICH.

Methods: Patients' basic characteristics and laboratory examination results, including the concentration of homocysteine, were taken at baseline from January 2014 to September 2016, and a 1 year follow-up, including the modified Rankin Scale and living status, was taken for all the patients. Logistic regression and Kaplan–Meier survival method were used to analyze the relationship between different Hcy levels and clinical outcome.

Results: A total of 551 patients with acute ICH from 13 hospitals in Beijing were enrolled in our study. High Hcy was detected in 284 patients (51.5%). Percentage of male, smoking, drinking, and concentration of hemoglobin A1c and triglyceride levels showed a significant difference between different Hcy level groups (all P-values <0.05). In the logistic regression analysis, high Hcy level is an independent risk factor for the prevalence of 3 month poor prognosis [odd ratio (95% confidence interval) = 1.601 (1.063–2.412), P = 0.0242], especially in female subgroup. In the 1 year follow-up period, high Hcy level patients had a significantly higher rate of fatal incidence compared to normal Hcy level patients (P = 0.0023).

Conclusions: High Hcy level was independently associated with poorer 3 month prognosis and a lower survival rate within 1 year in patients with ICH.

Vitamin D Deficiency Induces Elevated Oxidative and Biomechanical Damage in Coronary Arterioles in Male Rats

Background: Several reports prove interconnection between vitamin D (VD) deficiency and increased cardiovascular risk. Our aim was to investigate the effects of VD status on biomechanical and oxidative–nitrative (O–N) stress parameters of coronary arterioles in rats. Methods: 4-week-old male Wistar rats were divided into a control group (11 animals) with optimal VD supply (300 IU/kgbw/day) and a VD-deficient group (11 animals, <5 IU/kg/day). After 8 weeks, coronary arteriole segments were prepared. Geometrical, elastic, and biomechanical characteristics were measured by in vitro arteriography. O–N stress markers were investigated by immunohistochemistry. Results: Inner radius decreased; wall thickness and wall-thickness/lumen diameter ratio increased; tangential wall stress and elastic modulus were reduced in VD-deficient group. No difference could be found in wall-cross-sectional area, intima-media area %. While the elastic elements of the vessel wall decreased, the α-smooth muscle actin (α-SMA) immunostaining intensity showed no changes. Significant elevation was found in the lipid peroxidation marker of 4-hidroxy-2-nonenal (HNE), while other O–N stress markers staining intensity (poly(ADP)ribose, 3-nitrotyrosine) did not change. Conclusions: Inward eutrophic remodeling has developed. The potential background of these impairments may involve the initial change in oxidative damage markers (HNE). These mechanisms can contribute to the increased incidence of the cardiovascular diseases in VD deficiency.

Serum Homocysteine, Folate, and Vitamin B12 Levels in Patients with Systemic Lupus Erythematosus: A Meta-Analysis and Meta-Regression

BACKGROUND

Patients with systemic lupus erythematosus (SLE) have elevated cardiovascular risk. Hyperhomocysteinemia may be one of the contributing factors to this phenomenon. This study therefore aimed to compare the serum homocysteine levels and the levels of folate and vitamin B12, cofactors for homocysteine metabolism, between individuals with and without SLE.

METHODS

A literature search was performed in PubMed, Embase, and the Cochrane library (from inception to March 31, 2019). Studies comparing serum homocysteine, folate or vitamin B₁₂ levels between individuals with and without SLE were selected. Of the 1040 screened studies, 50 studies met the inclusion criteria.

RESULTS

A total of 50 studies involving 4396 patients with SLE were included. Patients with SLE had a significantly higher serum level of homocysteine (standardized mean difference [SMD], 1.134; 95% CI, 0.795-1.474) and lower level of vitamin B₁₂ (SMD, -0.359; 95% CI, -0.638 to -0.080) than controls. The folate level didn't differ markedly between SLE patients and the control group (SMD, -0.276; 95% CI, -0.674-0.123). Subgroup analysis showed consistent results in adult SLE patients. A random effects meta-regression analysis revealed a significantly inverse correlation between the SMD of homocysteine levels and C3 levels (coefficient, -0.0356, 95% CI, -0.054 to -0.0171; P < .001) and C4 levels (coefficient, -0.0876, 95% CI, -0.1407 to -0.0345; P = .0012).

CONCLUSIONS

Serum homocysteine levels were higher and vitamin B₁₂ levels were lower among individuals with SLE than those without SLE. Physicians are encouraged to monitor these parameters and offer timely interventions for patients with SLE.

Plasma Homocysteine and Autonomic Nervous Dysfunction: Association and Clinical Relevance in OSAS

Objective

Elevated plasma homocysteine (Hcy) is an independent risk factor for cardiovascular diseases, but the precise mechanism of Hcy in cardiovascular disease remains elusive. This study is aimed at evaluating the association between Hcy levels and autonomic nervous system and at investigating their clinical relevance in obstructive sleep apnea syndrome (OSAS).

Methods

A total of 191 subjects with OSAS were enrolled for this cross-sectional study. Heart rate variability (HRV) represents the status of the autonomic nervous system and is a well-known index that allows studying the autonomic modulation. HRV and polysomnography parameters were collected based on Holter monitors and polysomnography system. The software computed all the basic HRV parameters including SDANN, SDNN and pNN50. Correlation analyses between Hcy and HRV parameters and echocardiographic parameters were performed.

Results

Compared with the mild-moderate OSAS group, the prevalence of male and smoking and Hcy levels were considerably higher in the severe OSAS group (P = 0.01, P = 0.02, and P = 0.01, respectively). Also, there were significant linear relationships between Hcy quartiles with the proportion of severe OSAS (P = 0.01 for the trend). Interesting, there is a negative linear correlation between SDANN and Hcy quartiles (P = 0.02 for the trend). Spearman's correlation analysis showed a significant negative correlation between SDANN and Hcy levels (r = -0.17, P = 0.02). Interestingly, the relationship of it remains significant after adjustment for clinical covariates (r = -0.15, P = 0.04). However, echocardiographic parameters were not significantly correlated with Hcy or HRV parameters (all P > 0.05).

Conclusions

Elevated plasma Hcy level is linearly correlated with cardiac autonomic nervous function disorders in patients with OSAS.

Cystathionine-β-Synthase: Molecular Regulation and Pharmacological Inhibition

Cystathionine-β-synthase (CBS), the first (and rate-limiting) enzyme in the transsulfuration pathway, is an important mammalian enzyme in health and disease. Its biochemical functions under physiological conditions include the metabolism of homocysteine (a cytotoxic molecule and cardiovascular risk factor) and the generation of hydrogen sulfide (H2S), a gaseous biological mediator with multiple regulatory roles in the vascular, nervous, and immune system. CBS is up-regulated in several diseases, including Down syndrome and many forms of cancer; in these conditions, the preclinical data indicate that inhibition or inactivation of CBS exerts beneficial effects. This article overviews the current information on the expression, tissue distribution, physiological roles, and biochemistry of CBS, followed by a comprehensive overview of direct and indirect approaches to inhibit the enzyme. Among the small-molecule CBS inhibitors, the review highlights the specificity and selectivity problems related to many of the commonly used "CBS inhibitors" (e.g., aminooxyacetic acid) and provides a comprehensive review of their pharmacological actions under physiological conditions and in various disease models.

Inhibition of S-Adenosylhomocysteine Hydrolase Induces Endothelial Dysfunction via Epigenetic Regulation of p66shc-Mediated Oxidative Stress Pathway

BACKGROUND

Elevated levels of S-adenosylhomocysteine (SAH), the precursor of homocysteine, are positively associated with the risk of cardiovascular disease and with the development and progression of atherosclerosis. However, the role of SAH in endothelial dysfunction is unclear.

METHODS

Apolipoprotein E-deficient ( apoE^-/-) mice received dietary supplementation with the SAH hydrolase (SAHH) inhibitor adenosine dialdehyde or were intravenously injected with a retrovirus expressing SAHH shRNA. These 2 approaches, along with the heterozygous SAHH gene knockout ( SAHH^+/-) mouse model, were used to elevate plasma SAH levels and to examine the role of SAH in aortic endothelial dysfunction. The relationship between plasma SAH levels and endothelial dysfunction was also investigated in human patients with coronary artery disease and healthy control subjects.

RESULTS

Plasma SAH levels were increased in SAHH^+/- mice and in apoE^-/- mice after dietary administration of adenosine dialdehyde or intravenous injection with SAHH shRNA. SAHH^+/- mice or apoE^-/- mice with SAHH inhibition showed impaired endothelium-dependent vascular relaxation and decreased nitric oxide bioavailability after treatment with acetylcholine; this was completely abolished by the administration of the endothelial nitric oxide synthase inhibitor N^G-nitro-l-arginine methyl ester. Furthermore, SAHH inhibition induced production of reactive oxygen species and p66shc expression in the mouse aorta and human aortic endothelial cells. Antioxidants and p66shc siRNA prevented SAHH inhibition-induced generation of reactive oxygen species and attenuated the impaired endothelial vasomotor responses in high-SAH mice. Moreover, inhibition of SAHH induced hypomethylation in the p66shc gene promoter and inhibited expression of DNA methyltransferase 1. Overexpression of DNA methyltransferase 1, induced by transduction of an adenovirus, was sufficient to abrogate SAHH inhibition-induced upregulation of p66shc expression. Finally, plasma SAH levels were inversely associated with flow-mediated dilation and hypomethylation of the p66shc gene promoter and positively associated with oxidative stress levels in patients with coronary artery disease and healthy control subjects.

CONCLUSIONS

Our findings indicate that inhibition of SAHH results in elevated plasma SAH levels and induces endothelial dysfunction via epigenetic upregulation of the p66shc-mediated oxidative stress pathway. Our study provides novel molecular insight into mechanisms of SAH-associated endothelial injury that may contribute to the development of atherosclerosis.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov . Unique identifier: NCT03345927.

Modification of Platelet Count on the Association between Homocysteine and Blood Pressure: A Moderation Analysis in Chinese Hypertensive Patients

Background

Platelet consumption followed by homocysteine-induced endothelial injury suggests a crosstalk between platelet activation and homocysteine on hypertension. Platelet count has been found to modify the effect of folic acid on vascular health. However, whether platelet count could modify the contribution of homocysteine to blood pressure (BP) remains unclear.

Methods

Leveraging a community-based cross-sectional survey in 30,369 Chinese hypertensive patients (mean age 62 years, 52% female), we examined the moderation of platelet count on the association between serum homocysteine and BP by constructing hierarchical multiple regression models, adjusting for conventional risk factors. If adding the interaction term of homocysteine and platelet count could explain more variance in BP and the interaction is significant, then we believe that moderation is occurring.

Results

The association between serum homocysteine and diastolic BP was significantly stronger (β = 0.092 vs. 0.035, P = 0.004) in participants with low platelet count (<210 × 10⁹/L) than in those with high platelet count (≥210 × 10⁹/L). Adding the interaction term of homocysteine and platelet count additionally explained 0.05% of the variance in diastolic BP (P = 0.004) in participants with low platelet count (<210 × 10⁹/L) than in those with high platelet count (≥210 × 10⁹/L). Adding the interaction term of homocysteine and platelet count additionally explained 0.05% of the variance in diastolic BP (β = 0.092 vs. 0.035, P = 0.004) in participants with low platelet count (<210 × 10⁹/L) than in those with high platelet count (≥210 × 10⁹/L). Adding the interaction term of homocysteine and platelet count additionally explained 0.05% of the variance in diastolic BP (

Conclusions

The association between homocysteine and BP was significantly stronger in participants with low vs. high platelet count and was partially moderated by platelet count. These results indicate that platelet count may be useful in the identification of individuals who are most beneficial to reducing-homocysteine treatments but this usefullness still needs further investigation.

Serum/plasma homocysteine levels in patients with systemic lupus erythematosus: a systematic review and meta-analysis

Published studies have shown contradictory results in the association of serum/plasma levels of homocysteine (HCY) with systemic lupus erythematosus (SLE). This study is to systematically evaluate the association of serum/plasma HCY levels in SLE. A search was done using PubMed, Embase, Web of Science, and ScienceDirect databases up to 7 April 2019. Thirty-six articles including 2919 SLE patients and 3120 healthy controls were finally included in this meta-analysis. The HCY levels were significantly higher in SLE patients than in healthy controls (P < 0.001). The subgroup analysis revealed that Asian, African, Arab, Mixed, White and others as well as ages (< 35 and ≥ 35) had significant higher HCY levels in SLE patients than in the healthy controls. The study indicated that patients with disease activity index scores < 8 (P < 0.001) and ≥ 8 (P = 0.003) of SLE had significant higher HCY levels as compared with the healthy controls. It was also revealed that disease duration in SLE patients for < 10 and ≥ 10 years (P < 0.001) had significant higher HCY levels as compared with the healthy controls. A significant higher HCY level for body mass index (< 23 and ≥ 23) was found as well as measurement type in SLE patients than healthy controls. This meta-analysis demonstrated higher HCY levels in patients with SLE than healthy controls, suggesting a possible role of HCY in the disease.Key Points• Homocysteine (HCY) is closely related to the mechanisms of systemic lupus erythematosus (SLE).• This study reveals a significant correlation between HCY levels and the various indexes of disease activity.• This study reveals that medication may influence HCY levels in SLE.• This study also discovers that the subgroup analysis of all the factors influences the HCY levels in SLE patients.

Early Programming of Adult Systemic Essential Hypertension

Cardiovascular diseases are being included in the study of developmental origins of health and disease (DOHaD) and essential systemic hypertension has also been added to this field. Epigenetic modifications are one of the main mechanisms leading to early programming of disease. Different environmental factors occurring during critical windows in the early stages of life may leave epigenetic cues, which may be involved in the programming of hypertension when individuals reach adulthood. Such environmental factors include pre-term birth, low weight at birth, altered programming of different organs such as the blood vessels and the kidney, and living in disadvantageous conditions in the programming of hypertension. Mechanisms behind these factors that impact on the programming include undernutrition, oxidative stress, inflammation, emotional stress, and changes in the microbiota. These factors and their underlying causes acting at the vascular level will be discussed in this paper. We also explore the establishment of epigenetic cues that may lead to hypertension at the vascular level such as DNA methylation, histone modifications (methylation and acetylation), and the role of microRNAs in the endothelial cells and blood vessel smooth muscle which participate in hypertension. Since epigenetic changes are reversible, the knowledge of this type of markers could be useful in the field of prevention, diagnosis or epigenetic drugs as a therapeutic approach to hypertension.

Homocysteine and Hyperhomocysteinaemia

Homocysteine (Hcy) is a thiol group containing the amino acid, which naturally occurs in all humans. Hcy is degraded in the body through two metabolic pathways, while a minor part is excreted through kidneys. The chemical reactions that are necessary for degradation of Hcy require the presence of folic acid, vitamins B6 and B12. Consequently, the level of the total Hcy in the serum is influenced by the presence or absence of these vitamins. An elevated level of the Hcy, hyperhomocysteinemia (HHcy) and homocystinuria is connected with occlusive artery disease, especially in the brain, the heart, and the kidney, in addition to venous thrombosis, chronic renal failure, megaloblastic anemia, osteoporosis, depression, Alzheimer's disease, pregnancy problems, and others. Elevated Hcy levels are connected with various pathologies both in adult and child population. Causes of HHcy include genetic mutations and enzyme deficiencies in 5, 10-methylenetetrahydrofolate reductase (MTHFR) methionine synthase (MS), and cystathionine β-synthase (CβS). HHcy can be caused by deficiencies in the folate, vitamin B12 and to a lesser extent, deficiency in B6 vitamin what influences methionine metabolism. Additionally, HHcy can be caused by the rich diet and renal impairment. This review presents literature data from recent research related to Hcy metabolism and the etiology of the Hcy blood level disorder. In addition, we also described various pathological mechanisms induced by hereditary disturbances or nutritional influences and their association with HHcy induced pathology in adults and children and treatment of these metabolic disorders.

T-cell-derived extracellular vesicles regulate B-cell IgG production via pyruvate kinase muscle isozyme 2

Intercellular communication between lymphocytes plays a fundamental role in numerous immune responses. Previously, we demonstrated that hyperhomocysteinemia (HHcy) induced T cell intracellular glycolytic-lipogenic reprogramming and IFN-γ secretion via pyruvate kinase muscle isozyme 2 (PKM2) to accelerate atherosclerosis. Usually, B cells partially obtain help from T cells in antibody responses. However, whether PKM2 activation in T cells regulates B cell antibody production is unknown. Extracellular vesicles (EVs) are important cellular communication vehicles. Here, we found that PKM2 activator TEPP46-stimulated T-cell-derived EVs promoted B-cell IgG secretion. Conversely, EVs secreted from PKM2-null T cells were internalized into B cells and markedly inhibited B-cell mitochondrial programming, activation, and IgG production. Mechanistically, lipidomics analyses showed that increased ceramides in PKM2-activated T-cell EVs were mainly responsible for enhanced B cell IgG secretion induced by these EVs. Finally, quantum dots (QDs) were packaged with PKM2-null T cell EVs and anti-CD19 antibody to exert B-cell targeting and inhibit IgG production, eventually ameliorating HHcy-accelerated atherosclerosis in vivo. Thus, PKM2-mediated EV ceramides in T cells may be an important cargo for T-cell-regulated B cell IgG production, and QD-CD19-PKM2-null T cell EVs hold high potential to treat B cell overactivation-related diseases.-Yang, J., Dang, G., Lü, S., Liu, H., Ma, X., Han, L., Deng, J., Miao, Y., Li, X., Shao, F., Jiang, C., Xu, Q., Wang, X., Feng, J. T-cell-derived extracellular vesicles regulate B-cell IgG production via pyruvate kinase muscle isozyme 2.

Putative Nox2 inhibitors worsen homocysteine-induced impaired acetylcholine-mediated relaxation

BACKGROUND AND AIM

Increased homocysteine (Hcy) is associated with coronary artery disease (CAD). Hcy increases reactive oxygen species (ROS) via NADPH oxidases (Nox), reducing acetylcholine-mediated vasorelaxation. We aimed to determine if putative Nox2 inhibitors prevent Hcy-impaired acetylcholine-mediated vasorelaxation.

METHODS AND RESULTS

New Zealand White rabbit and wild-type (C57BL/6) and Nox2^-/- (NOX) mice aortic rings were mounted in organ baths. Rabbit rings were incubated with either apocynin (10 μM), gp91ds-tat (GP, 1 μM) or PhoxI2 (1 μM) and mice rings GP (1 μM) only. Some rabbit rings were incubated with 3 mM Hcy, before pre-contraction, followed by dose-response relaxation to acetylcholine (ACh; 0.01μM-10μM). In rabbit rings treated with Hcy and GP, O₂‾ donor pyrogallol (1 μM) or Akt activator SC79 (1 μM) was added 5 min before ACh. Mice rings were used to compare Nox2 deletion to normal acetylcholine-mediated relaxation. In rabbits, Hcy reduced acetylcholine-mediated relaxation vs. control (p < 0.0001). Treatment + Hcy reduced relaxation compared with treatment alone (p < 0.0001). Pyrogallol and SC79 reversed the response of GP + Hcy (p = 0.0001). In mice, Nox2 deletion reduced acetylcholine-mediated vasorelaxation. Rabbit tissue analysis revealed that Hcy reduced eNOS phosphorylation at Thr⁴⁹⁵ and increased eNOS phosphorylation at Ser¹¹⁷⁷; no further alteration at Thr⁴⁹⁵ was observed with GP. In contrast, GP prevented increased phosphorylation at Ser¹¹⁷⁷.

CONCLUSIONS

Apocynin, GP and PhoxI2 worsens acetylcholine-mediated vascular relaxation in rabbit aorta, which is supported by results from mouse Nox2 deletion data. These inhibitors worsen Hcy-induced vascular dysfunction, suggesting that current putative Nox2 inhibitors might not be useful in treating HHcy.

Cardiovascular risk factors in noise-exposed workers in china: Small area study

Introduction:

The aim of the present study was to evaluate whether there are changes in cardiovascular risk factors among noise-exposed workers and to explore the possible mechanisms of a long-term noise exposure leading to cardiovascular disease and the sex differences of cardiovascular risk factors in this population.

Materials and Methods:

Two hundred workers engaged in noise-related work, and a control group of 200 nonnoise-exposed workers hospitalized for occupational health examination were assigned into the study. All workers underwent a medical examination, electrocardiogram recording, blood pressure test, other blood tests, and audiometry. The collected blood was used to detect homocysteine (HCY), renin, angiotensin II, and other markers of cardiovascular risk factors.

Results:

Our study suggests that the type of work with long-term exposure to noise might pose a cardiovascular risk, as evidenced by associated increases in plasma HCY levels, incidence of type 2 diabetes, and incidence of hypertension.

Discussion:

Our research also reveals that among male workers, the levels of triglycerides, uric acid, HCY, renin activity, and the incidence of hypertension are higher than female, while high-density lipoprotein cholesterol is lower than female workers had. Additionally, the study emphasizes again the importance of weight control for reducing cardiovascular risk.

Conclusion:

Our study suggests that noise is a cardiovascular risk factor. Interventions in the work environment could be a preventable and controllable manner for reducing the incidence of cardiovascular disease.

Possible Role of N-Methyl-D-Aspartate Receptors in Physiology and Pathophysiology of Cardiovascular System

N-methyl-D-aspartate (NMDA) receptors belong to ionotropic glutamate receptor family, together with α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, kainite receptors and δ-receptors. All of these receptors are tetramers composed of four subunits. NMDA receptors have several unique features in relation to other ionotropic glutamate receptors: requirement for simultaneous action of two coagonists, glutamate and glycine; dual control of receptor activation, ligand-dependent (by glutamate and glycine) and voltage-dependent (Mg2+ block) control; and influx of considerable amounts of Ca2+ following receptor activation. Increasing number of researches deals with physiological and pathophysiological roles of NMDA receptors outside of nerve tissues, especially in the cardiovascular system. NMDA receptors are found in all cell types represented in cardiovascular system, and their overstimulation in pathological conditions, such as hyperhomocysteinemia, is related to a range of cardiovascular disorders. On the other hand we demonstrated that blockade of NMDA receptors depresses heart function. There is a need for the intensive study of NMDA receptor in cardiovascular system as potential theraputical target both in prevention and treatment of cardiovascular disorders.

Homocysteine-lowering exercise effect is greater in hyperhomocysteinemic people living with HIV: a randomized clinical trial

Elevated concentration of homocysteine has been identified as an independent risk factor for the development of cardiovascular disease and is frequently associated with oxidative stress. Moreover, studies have shown that people living with human immunodeficiency virus (PLHIV) present elevated concentration of homocysteine and oxidative stress compared with people without HIV. Our purpose was to describe blood homocysteine and oxidative stress markers in PLHIV and those without HIV infection, and to examine the effects of a 16-week combined training exercise program (CTE) on oxidative stress and homocysteine concentrations of PLHIV. We included 49 PLHIV (21 men, 28 women) and 33 people without HIV infection (13 men, 20 women). After baseline evaluations, 30 PLHIV were randomized to either CTE (trained group, n = 18) or the control group (n = 12); CTE consisted of aerobic and strength exercise sessions during 16 weeks, 3 times a week. Plasma homocysteine, oxidative damage markers, folate, and vitamin B₁₂ were assessed pre- and post-training and by hyperhomocysteinemia (homocysteine ≥ 15 μmol/L) status. At baseline, PLHIV had higher levels of homocysteine and malondialdehyde, as well as reduced circulating folate when compared with people without HIV infection. CTE resulted in a 32% reduction (p < 0.05) in homocysteine concentration and a reduction in lipid hydroperoxide in PLHIV with hyperhomocysteinemia, which was not observed in those without hyperhomocysteinemia. Hyperhomocysteinemic participants experienced a 5.6 ± 3.2 μmol/L reduction in homocysteine after CTE. In summary, 16 weeks of CTE was able to decrease elevated homocysteine concentration and enhance redox balance of PLHIV with hyperhomocysteinemia, which could improve their cardiovascular risk.

Ganoderma triterpenes Protect Against Hyperhomocysteinemia Induced Endothelial-Mesenchymal Transition via TGF-β Signaling Inhibition

Endothelial dysfunction is one of the most important pathological status in hyperhomocysteinemia (HHcy) related cardiovascular diseases. Whereas, the underlying mechanisms have not been fully elucidated yet, concomitant with the absence of effective treatment. The purpose of this study was to explore the main mechanisms involved in HHcy-induced endothelial injury and identify the protective effect of Ganoderma triterpenes (GT). Bovine aortic endothelial cells (BAECs) were applied as in vitro experimental model. The small molecular inhibitors were used to explore the signalings involved in HHcy-induced endothelial injury. The experimental results provided initial evidence that HHcy led to endothelial-mesenchymal transition (EndMT). Meanwhile, TGF-β/Smad, PI3K/AKT and MAPK pathways were activated in this process, which was demonstrated by pretreatment with TGF-β RI kinase inhibitor VI SB431542, PI3K inhibitor LY294002, p38 inhibitor SB203580, and ERK inhibitor PD98059. Furthermore, it was found that GT restrained the process of HHcy-induced EndMT via reducing oxidative stress and suppressing fore mentioned pathways with further inhibiting the activity of Snail. These results implicate that there is an untapped potential for GT as a novel therapeutic candidate for HHcy-induced EndMT through alleviating oxidative stress and canonical TGF-β/Smad and non-Smad dependent signaling pathways.

Homocysteine and homocysteine-related compounds: an overview of the roles in the pathology of the cardiovascular and nervous systems

Homocysteine, an amino acid containing a sulfhydryl group, is an intermediate product during metabolism of the amino acids methionine and cysteine. Hyperhomocysteinemia is used as a predictive risk factor for cardiovascular disorders, the stroke progression, screening for inborn errors of methionine metabolism, and as a supplementary test for vitamin B₁₂ deficiency. Two organic systems in which homocysteine has the most harmful effects are the cardiovascular and nervous system. The adverse effects of homocysteine are achieved by the action of several different mechanisms, such as overactivation of N-methyl-d-aspartate receptors, activation of Toll-like receptor 4, disturbance in Ca²⁺ handling, increased activity of nicotinamide adenine dinucleotide phosphate-oxidase and subsequent increase of production of reactive oxygen species, increased activity of nitric oxide synthase and nitric oxide synthase uncoupling and consequent impairment in nitric oxide and reactive oxygen species synthesis. Increased production of reactive species during hyperhomocysteinemia is related with increased expression of several proinflammatory cytokines, including IL-1β, IL-6, TNF-α, MCP-1, and intracellular adhesion molecule-1. All these mechanisms contribute to the emergence of diseases like atherosclerosis and related complications such as myocardial infarction, stroke, aortic aneurysm, as well as Alzheimer disease and epilepsy. This review provides evidence that supports the causal role for hyperhomocysteinemia in the development of cardiovascular disease and nervous system disorders.

Influence of age and gender on blood pressure variability and baroreflex sensitivity in a healthy population in the Indian sub-continent

Background The current exploratory study was aimed at estimating measures of blood pressure variability (BPV) and baroreflex sensitivity (BRS) in a healthy population in the Indian sub-continent. Methods One hundred and forty-two healthy subjects were recruited for the study. Blood pressure (BP) was recorded continuously for 15 min using the Finometer (Finapres Medical Systems, The Netherlands). For offline analysis, Nevrokard cardiovascular parameter analysis (CVPA) software (version 2.1.0) was used for BPV analysis. BRS was determined by spectral and sequence methods. One-way ANOVA and Bonferroni's test were used to compare parameters. Pearson's correlation coefficient was employed to look for possible associations between age and other continuous variables. Results Out of 196 screened volunteers, 54 were excluded and 142 subjects were grouped based on ages as 10-19 years (group 1), 20-29 years (group 2), 30-39 years (group 3), 40-49 years (group 4), and 50-59 years (group 5). Within groups, body mass index (BMI, p=0.000) and BP (systolic and diastolic) were significantly different. Post hoc analysis showed mean blood pressure (MBP) and diastolic blood pressure (DBP) differing significantly between groups 1 and 4 (p<0.05 for both) along with other cardiovascular parameters. Age correlated positively with BMI and all parameters of BP. Significant gender differences were observed for stroke volume, cardiac output, up BRS, total BRS, peripheral resistance (PR), and aortic impedance. Conclusions Our study has provided reference values for BPV and BRS in an Indian population. It also indicates age-related neurocardiac imbalance and possible utility of these tests for screening at the start of neurocardiac damage in a healthy population.

ADMA, homocysteine and redox status improvement affected by 7-nitroindazole in spontaneously hypertensive rats

Inhibition of nitric oxide (NO) production can influence blood pressure regulation and increase hypertension. Asymmetric dimethylarginine, ADMA, an analogue of L-arginine, can inhibit NO synthesis, impair endothelial function, and is a risk marker of cardiovascular diseases. Homocysteine (Hcy) level affects oxidative stress production of reactive oxygen species (ROS) in hypertension and also influences changes in signaling and cell damage. The present study was focused on experimental effects of exogenous NOS inhibitors and their effect on ADMA, an endogenous NOS inhibitor, homocysteine and ROS production measured as reactive oxidative metabolites (ROM). We compared effects of the two potential exogenous NO-inhibitors: N^G-nitro L-arginine methyl ester (L-NAME) and 7-nitroindazole (7-NI). Levels of ADMA, Hcy, ROM and total thiols (TTL) were not changed in the L-NAME group. With 7-NI administration, we observed unchanged NOS activity in the left ventricle and a pronounced decrease of ADMA and Hcy levels, accompanied by ROM over-production in plasma. TTL/ROM ratio was more favorable than in the L-NAME group. We observed that 7-NI, an exogenous NOinhibitor, can decrease and improve the levels of ADMA, Hcy, and ROM, and increase TTL/ROM ratio in the plasma of spontaneously hypertensive rats.