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Sulfur-containing amino acids are integral part of molecular mechanisms which underlie many aspects of cellular function and homeostasis, facilitated by reversible changes in oxidation states of sulfur atoms. Dysregulation of these pathways is associated with diverse pathologies, notably of the cardiovascular system, which are typically characterized by inappropriate plasma levels of sulfur-containing amino acids. The aim of this study was to assess the acute, direct effects of sulfur-containing amino acids and inorganic NaHS, as H2S donor, on cardiodynamic parameters in homocysteine treated rats. Moderate hyperhomocysteinemia did not cause significant decrease in myocardial contractility, but our findings suggest that NaHS and L-methionine cause negative effects on cardiac function in hearts of the rats treated with homocysteine, even in a single administration. Further investigations need to be carried out with purpose of better understanding and highlightening the impact of Hcy and sulphur amino acids on cardiac function.

Background/Aim. Previous studies have confirmed a positive correlation between homocysteine levels and a greater risk for acute coronary syndrome and stroke, but there are no available data to support an association between homo-cysteine and inflammatory markers and the severity of coronary artery disease according to the clinical SYNTAX score in patients with stable angina. The aim was to determine the association between homocysteine and inflammatory biomarker levels: interleukin (IL)-6, high sensitive C-reactive protein (hs-CRP), fibrinogen, erythrocyte sedimentation rate (ESR) and the severity of coronary artery disease according to clinical SYNTAX score. Methods. Eighty-two patients with stable angina pectoris (average age 65 ? 8 years, 28.9% females) underwent coronary angiography and were divided into three groups according to the clinical SYNTAX score: the group I < 22 (39 patients), the group II 23?32 (16 patients), the group III > 33 (27 patients). The severity and complexity of coronary artery disease were calculated by clinical SYNTAX score, multiplying the SYN-TAX score with the modified ACEF score, based on the patients? left ventricular ejection fraction, age and creatinine clearance (derived with Cockcroft?Gault equation). Results. Homocysteine levels were significantly higher in patients with high clinical SYNTAX score [the group I: median (interquartile range ? IQR): 10.20 (3.97), the group II: 10.45 (5.77), the group III: 14.70 (7.50), p = 0.005]. Patients in the group III had significantly higher homocysteine levels compared to the group I (p = 0.001). We also found a posi-tive association between inflammatory biomarkers (IL-6, hsCRP, fibrinogen, ESR) and the severity of coronary artery disease according to the clinical SYNTAX score (p = 0.017, 0.001, 0.032, 0.049 respectively). We detected significantly lower plasma levels of vitamin B12 in the group III and group II in comparison with the group I (the group I: median (IQR): 238 (160), the group II: 171 (160), the group III: 172 (102), p = 0.022), which indicates its important role in homocysteine metabolism. Conclusion. The elevated plasma levels of homocysteine, IL-6, hsCRP, fibrinogen, ESR were detected in patients with high clinical SYNTAX score (> 33). Our results showed that hyperhomocysteinemia and some inflammatory biomarkers can predict more severe and extensive coronary artery disease in stable angina patients.

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Heart failure (HF) is one of the major cardiovascular causes of death worldwide. In this study, we explored the effects of folic acid (FA) on cardiometabolic, oxidative stress biomarker changes, and the activity of proliferation marker Ki67 in monocrotaline-induced HF. The research was conducted during a 4 week period using five experimental groups (eight animals per group): blank solution exposed controls (C1: 1 mL/kg physiological saline, 1 day; C2: 1 mL/kg physiological saline, 28 days), monocrotaline (MCT) induced HF (50 mg/kg MCT), FA (5 mg·kg−1·day−1FA), and MCT+FA (50 mg/kg MCT, 5 mg·kg−1·day−1FA). Superoxide dismutase and glutathione peroxidase activities together with total glutathione and parameters of oxidative damage of proteins were determined in cardiac tissue as well as cardiometabolic parameters in plasma or serum. The total glutathionylation was determined by Western blot and proliferation marker Ki67 was assessed by immunohistochemistry. The right ventricular (RV) wall hypertrophy and Ki67 positivity, accompanied by a significant increase of troponin T, has been shown in MCT-induced HF. The antioxidant effect of FA was reflected through superoxide dismutase activity, reduced Ki67 positivity in the RV wall, and a slightly decreased total glutathionylation level.

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.

The aim of this study was to test the hypothesis that subchronic co-application of vitamins B6 and folic acid (FA) could affect heart failure (HF) induced by monocrotaline (MCT), with the modulation of oxidative stress parameters and cardiometabolic biomarkers. Biochemical and histomorphometric analyses were assessed in blank solution-exposed controls (C1 physiological saline 1 mL/kg, 1 day, n = 8; C2 physiological saline 1 mL/kg, 28 days, n = 8), MCT-induced HF (MCT 50 mg/kg, n = 8), B6+FA (vitamin B6 7 mg·kg–1·day–1, FA 5 mg·kg–1·day–1; n = 8), and MCT+B6+FA (MCT 50 mg/kg, vitamin B6 7 mg·kg–1·day–1, FA 5 mg·kg–1·day–1; n = 8) in male Wistar albino rats (body mass 160 g at the start). Superoxide dismutase and glutathione peroxidase activities, thiol-, carbonyl groups, and nitrotyrosine were determined in cardiac tissue. Echocardiography was performed to confirm MCT-induced HF. The right ventricular wall hypertrophy, accompanied with significant increase of troponin T and preserved renal and liver function, has been shown in MCT-induced HF. However, these effects were not related to antioxidant effects of vitamin B6 and FA, since several parameters of oxidative stress were more pronounced after treatment. In this study, co-application of vitamins B6 and FA did not attenuate hypertrophy of the right ventricle wall but aggravated oxidative stress, which is involved in HF pathogenesis.

Diabetes mellitus (DM) is a metabolic disorder that causes severe complications. Thus, the aims of this study were to investigate the influence of DM and folic acid treatment on liver and renal biomarkers, and heart remodeling through evaluation of cardiac matrix metalloproteinase (MMP) activity. There were 4 groups: control (physiological saline 1 mL/kg, i.p., 28 days), DM (streptozotocin [STZ] 100 mg/kg in physiological saline, i.p., 1 day), folic acid (FA; 5 mg/kg, i.p., 28 days), and DM+FA (STZ 100 mg/kg, i.p., 1 day and folic acid 5 mg/kg, i.p., 28 days). Our results demonstrated increased aminotransferase and alkaline phosphatase activity, urea and creatinine concentration, and decreased albumin and fibrinogen concentration in the DM group. MMP-2 relative activity was elevated in the DM and FA groups; MMP-9 was decreased in the DM and increased in the FA group. The folic acid treatment of diabetic rats did not change aminotransferase activity; it alleviated the increase in alkaline phosphatase and the decrease in albumin and fibrinogen concentration, and reduced MMP-2 activity; however, it increased urea and creatinine concentration. In conclusion, folic acid treatment of diabetic rats has cardio- and hepato-protective effects. However, its dosing should be carefully considered because of possible renal damage.

The aim of this study was to examine the effects of folic acid administration on the antioxidant enzyme (superoxide dismutase (SOD) and catalase (CAT)) activities, lactate and malate dehydrogenase (LDH and MDH) activities, and certain LDH and MDH isoform distribution in the cardiac tissue of diabetic Wistar male rats. Diabetes mellitus (DM) was induced by streptozotocin (STZ). There were five groups: C1—control (physiological saline 1 ml/kg, i.p. one day), C2—control with daily physiological saline treatment (1 ml/kg, i.p. 28 days), DM—diabetes mellitus (STZ 100 mg/kg in physiological saline, i.p. one day), FA—folic acid (5 mg/kg in physiological saline, i.p. 28 days), and DM+FA—diabetes mellitus and folic acid group (STZ 100 mg/kg in physiological saline, i.p. one day, and folic acid 5 mg/kg in physiological saline, i.p. 28 days). After four weeks, animal hearts were isolated for measurement of enzyme activities, as well as for histomorphometry analyses. An elevated glucose level and a decreased insulin level were obtained in the DM group. SOD, CAT, and MDH activities were elevated in the DM group, while there was no difference in LDH activity among the groups. In all tested groups, four LDH and three MDH isoforms were detected in the heart tissue, but with differences in their relative activities among the groups. Left ventricular cardiomyocyte transversal diameters were significantly smaller in both diabetic groups. Folic acid treatment of diabetic rats induced a reduced glucose level and reduced CAT, SOD, and MDH activities and alleviated the decrease in cardiomyocyte diameters. In conclusion, increased activities of antioxidant enzymes and MDH may be the consequence of oxidative stress caused by DM. Administration of the folic acid has a protective effect since it leads to reduction in glycemia and activities of the certain examined enzymes in the rats with experimentally induced DM.

Inflammation is a marker of arterial disease stemming from cholesterol-dependent to -independent molecular mechanisms. In recent years, the role of inflammation in atherogenesis has been underpinned by pharmacological approaches targeting systemic inflammation that have led to a significant reduction in cardiovascular disease (CVD) risk. Although the use of nutraceuticals to prevent CVD has largely focused on lipid-lowering (e.g, red-yeast rice and omega-3 fatty acids), there is growing interest and need, especially now in the time of coronavirus pandemic, in the use of nutraceuticals to reduce inflammatory markers, and potentially the inflammatory CVD burden, however, there is still not enough evidence to confirm this. Indeed, diet is an important lifestyle determinant of health and can influence both systemic and vascular inflammation, to varying extents, according to the individual nutraceutical constituents. Thus, the aim of this Position Paper is to provide the first attempt at recommendations on the use of nutraceuticals with effective anti-inflammatory properties.

Glioblastoma multiforme and anaplastic astrocytoma represent one of the most frequently occurring primary brain tumors with dismal survival rates. The aim of our study was to investigate whether values of homocysteine, folates and vitamin B12 can be prognostic markers in relapse diagnosis, treatment and monitoring of adult patients with malignant brain tumors.Twenty-seven patients from the Neurosurgical Clinic, Clinical Center of Serbia with diagnosed malignant brain tumors (anaplastic astrocytoma GR III and glioblastoma multiforme GR IV), were included in the study. The patients were divided in two groups according to the progression of disease, 15 with and 12 without progression.Mean values of homocysteine were significantly higher in the group with progression compared to the group without malignant tumor progression, at the baseline point and after six months. Mean values of folate were similar across groups in all measurements, except in the 3rd month after surgery. Results regarding vitamin B12 were similar to folate, without any significance in group comparisons in the examined time points, as well as in vitamin B12 values change.Our results pointed out that total homocysteine in blood circulation appears to be a tumor marker for monitoring primary malignant brain tumor patients before and after surgery. The association of hyperhomocysteinemia with folate deficiency, also provides strong support for viewing hyperhomocysteinemia as a predictive marker for carcinogenesis. It is hoped that future research will continue to explore the clinical relevance of homocysteine as a tumor marker and a risk factor for astrocytoma and glioblastoma.

Background In most cases coronary artery disease (CAD) and carotid artery disease exist at the same time and both represent the most serious manifestation of systemic atherosclerosis. Chronic coronary syndrome (CSS) includes six different clinical scenarious, and patients with stable angina symptoms and/or dyspnoea were comprised in our study. A previous studies have demonstrated that patients with myocardial infarction have more severe carotid artery disease, but there are no available data regarding association between SYNTAX I score (SS) and carotid intima-media thickness (CIMT) in patients with CSS. SS is known as universal angiographic scoring system, entirely based on coronary anatomy and lesion characteristics. CIMT measurement is a non-invasive tool to diagnose early atherosclerosis. Purpose The aim of this study was to determine the correlation between SS and CIMT in patients with with CSS. Methods A total of 82 CSS patients (average age 61±12 years, 28.9% females) underwent exercise ECG or stress echocardiography. Coronary angiography and ultrasonography of internal carotid artery were performed and patients were divided into three groups according to SS: Group I (33, n=20). We also estimate the severity of CAD according to clinical SYNTAX. Simultaneously, we evaluate whether biomarkers of hemostasis and thrombosis, such as fibrinogen, plasminogen activator inhibitor (PAI-1), D dimer, coagulation factor VIII and von Willebrand factor (VWF), as well as homocysteine and C reactive protein (hs CRP) were associated with CAD complexity. Results There were significant correlation between severity of CAD according to SYNTAX I score and CIMT (Group I: 1.23±0.27, II: 1.56±0.43, III 1.43±0.21, Kruskal Wallis p=0.000). In order to estimate the impact of atherosclerosis burden on CAD complexity, patients were divided into 3 groups according to CIMT: low (0.05). We didn't find positive association between clinical SYNTAX I score and CIMT (p>0.05). Conclusion Patients with chronic coronary syndrome and severe carotid artery disease according to CIMT (≥1.31) had higher SS and more complex CAD. Elevated biomarkers of hemostasis and thrombosis such as fibrinogen, VWF and factor VIII, as well as homocysteine and CRP may be a mutual casual factors for associated polyvascular disease. Correlation between CIMT and SS Funding Acknowledgement Type of funding source: None

As well as the most known role of N-methyl-D-aspartate receptors (NMDARs) in the nervous system, there is a plethora of evidence that NMDARs are also present in the cardiovascular system where they participate in various physiological processes, as well as pathological conditions. The aim of this study was to assess the effects of preconditioning and postconditioning of isolated rat heart with NMDAR agonists and antagonists on heart function and release of oxidative stress biomarkers. The hearts of male Wistar albino rats were subjected to global ischemia for 20 min, followed by 30 min of reperfusion, using the Langendorff technique, and cardiodynamic parameters were determined during the subsequent preconditioning with the NMDAR agonists glutamate (100 &micro, mol/L) and (RS)-(Tetrazol-5-yl)glycine (5 &mu, mol/L) and the NMDAR antagonists memantine (100 &mu, mol/L) and MK-801 (30 &mu, mol/L). In the postconditioning group, the hearts were perfused with the same dose of drugs during the first 3 min of reperfusion. The oxidative stress biomarkers were determined spectrophotometrically in samples of coronary venous effluent. The NMDAR antagonists, especially MK-801, applied in postconditioning had a marked antioxidative effect with a most pronounced protective effect. The results from this study suggest that NMDARs could be a potential therapeutic target in the prevention and treatment of ischemic and reperfusion injury of the heart.

This study was conducted to explore the effects of sulfur containing amino acids on redox status and morphological parameters in the rat ileum tissue. Male Wistar albino rats were randomly divided into the following groups: Group K (saline (1 ml/day, i.p.)), Group M (methionine (0.8 mmol/kg/day, i.p.)), Group C (methionine (0.8 mmol/kg/day) + L-cysteine (7 mg/kg/day), i.p.) and Group N (methionine (0.8 mmol/kg/day) + N-acetyl-L-cysteine (50 mg/kg/day), i.p.). Activities of antioxidant enzymes in the ileum were analyzed to profile oxidative status. Morphometric analysis included measurement of villus height (μm), tunica mucosa thickness (μm), tunica muscularis thickness (μm), the total thickness of the ileal wall (μm) and the number of cells in the lamina propria (per 0.1 mm2 of tissue). Results showed that methionine treatment reduced the activity of antioxidant enzymes (SOD, GPx, CAT) and the GSH content compared to the control group (p > 0.05). The application of methionine reduced the following parameters statistically significant compared to the control group: length of the ileal villi (p < 0.01), tunica mucosa thickness (p < 0.01), and ileal wall thickness (p < 0.01). We concluded that methionine induced the changes in the gut redox status, which implied oxidative stress occurrence. L-cysteine and N-acetyl-L-cysteine both exhibited antioxidant properties.

This article presents a systematic approach to defining, applying, evaluating, refining, and revising metrics for students’ soft skills—their abilities like critical thinking, problem solving, lead...

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 B12deficiency. 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.

Methionine is the precursor of homocysteine, a sulfur amino acid intermediate in the methylation and transsulfuration pathways; methionine-rich diets were used to induce hyperhomocysteinemia, and cardiovascular pathology was often observed. Other sulfur amino acids interfere with this metabolism, i.e., L-cysteine (Cys) and N-aceyl-L-cysteine (NAC), and probably also affect cardiovascular system. Their effects are controversial due to their ability to act both as anti- or pro-oxidant. Thus, this study aimed to elucidate their influence on levels of homocysteine, folate and vitamin B12, levels of different haemostatic parameters (fibrinogen, D-dimer, vWF Ag, vWF Ac) in rat serum or plasma as well as their effects on cardiac and aortic tissue histology in subchronically methionine-treated rats. Wistar albino rats were divided into 4 experimental groups: (a) control group (0.9% sodium chloride 0.1-0.2 mL/day) (n = 10) (K); (b) DL-methionine (0.8 mmol/kg/bw/day) (n = 10) (M); (c) DL-methionine (0.8 mmol/kg/bw/day) + L-cysteine (7 mg/kg/bw/day) (n = 8) (C); (d) DL-methionine (0.8 mmol/ kg/bw/day) + N-acetyl-L-cysteine (50 mg/kg/bw/day) (n = 8) (N). All substances were applied i.p., treatment duration 3 weeks. Lower levels of vitamin B12 in all the groups were found. Folate was reduced only in N group. Decreased fibrinogen was noted in C and N groups and increased D-dimer only in C. VWF activity was reduced in M and C groups. Deleterious effects in heart were observed, especially after Cys and NAC application. Aortic tissue remained unchanged. In conclusion, it could be said that sulfur amino acids have the significant impact on cardiovascular system in subchronically methionine-treated rats. This study points out the relevance of their complex interactions and deleterious effects mediated by either direct influence or procoagulant properties.

This research is designed to test the hypothesis that elevated homocysteine (Hcy) levels in vivo, caused by a deficit in vitamin B complex, promote changes in cardiac function and redox status that lead to heart failure. In order to conduct the study, we used adult male Wistar albino rats (n = 30; 4 weeks old; 100 ± 15 g body weight). Hyperhomocysteinaemia (HHcy) in these animals was achieved by dietary manipulation. For 4 weeks, the animals were fed with a standard rodent chow (control, CF), a diet enriched in methionine with no deficiency in B vitamins (i.e., folic acid, B6 and B12) (HMNV) or a diet enriched in methionine and deficient in B vitamins (HMLV). After 28 days of dietary manipulation, all animals were killed. The rat hearts were isolated and retrogradely perfused according to the Langendorff technique at a gradually increasing perfusion pressure. We found a negative correlation between elevated serum Hcy and total body and heart weight. The maximum rate of left ventricular pressure development was significantly increased in the HMNV group compared with in the other groups. Systolic left ventricular pressure was significantly changed in all groups. HHcy induces remodelling of the cardiac tissues, as moderate HHcy is associated with more prominent interstitial and perivascular fibrosis. Our results suggest that a high methionine diet without vitamin B complex causes profound negative effects associated with HHcy.