Electrophysiological Impact of SARS-CoV-2 Envelope Protein in U251 Human Glioblastoma Cells: Possible Implications in Gliomagenesis?

SARS-CoV-2 is the causative agent of the COVID-19 pandemic, the acute respiratory disease which, so far, has led to over 7 million deaths. There are several symptoms associated with SARS-CoV-2 infections which include neurological and psychiatric disorders, at least in the case of pre-Omicron variants. SARS-CoV-2 infection can also promote the onset of glioblastoma in patients without prior malignancies. In this study, we focused on the Envelope protein codified by the virus genome, which acts as viroporin and that is reported to be central for virus propagation. In particular, we characterized the electrophysiological profile of E-protein transfected U251 and HEK293 cells through the patch-clamp technique and FURA-2 measurements. Specifically, we observed an increase in the voltage-dependent (Kv) and calcium-dependent (KCa) potassium currents in HEK293 and U251 cell lines, respectively. Interestingly, in both cellular models, we observed a depolarization of the mitochondrial membrane potential in accordance with an alteration of U251 cell growth. We, therefore, investigated the transcriptional effect of E protein on the signaling pathways and found several gene alterations associated with apoptosis, cytokines and WNT pathways. The electrophysiological and transcriptional changes observed after E protein expression could explain the impact of SARS-CoV-2 infection on gliomagenesis.

Electro-Metabolic Coupling of Cumulus-Oocyte Complex.

Oocyte-cumulus cell interaction is essential for oocyte maturation and competence. The bidirectional crosstalk network mediated by gap junctions is fundamental for the metabolic cooperation between these cells. As cumulus cells exhibit a more glycolytic phenotype, they can provide metabolic substrates that the oocyte can use to produce ATP via oxidative phosphorylation. The impairment of mitochondrial activity plays a crucial role in ovarian aging and, thus, in fertility, determining the success or failure of assisted reproductive techniques. This review aims to deepen the knowledge about the electro-metabolic coupling of the cumulus-oocyte complex and to hypothesize a putative role of potassium channel modulators in order to improve fertility, promote intracellular Ca2+ influx, and increase the mitochondrial biogenesis and resulting ATP levels in cumulus cells.

Focus on the Use of Resveratrol in Bladder Cancer.

Bladder cancer is the most common tumor of the urinary system, with a high incidence in the male population. Surgery and intravesical instillations can eradicate it, although recurrences are very common, with possible progression. For this reason, adjuvant therapy should be considered in all patients. Resveratrol displays a biphasic dose response both in vitro and in vivo (intravesical application) with an antiproliferative effect at high concentrations and antiangiogenic action in vivo (intraperitoneal application) at a low concentration, suggesting a potential role for it in clinical management as an adjuvant to conventional therapy. In this review, we examine the standard therapeutical approach to bladder cancer and the preclinical studies that have investigated resveratrol in xenotransplantation models of bladder cancer. Molecular signals are also discussed, with a particular focus on the STAT3 pathway and angiogenic growth factor modulation.

Weight is an independent predictor of vascular injury in healthy volunteers with aspartate allele.

BACKGROUND: Endothelial dysfunction and carotid intima-media thickeness (IMT) are currently considered key early events in atherogenesis and markers of arterial damage. We investigated whether endothelial nitric oxide synthase (eNOS) glutamate (Glu)298-aspartate (Asp) polymorphism may influence the vascular response to weight, as measured by BMI, in young, healthy individuals. METHODS: One hundred young (30.6 ±â€Š5.9 years) healthy individuals, without concomitant traditional cardiovascular risk factors took part in the study. Brachial artery endothelial function was assessed by vascular response to reactive hyperemia [flow-mediated dilation (FMD) and sublingual nitroglycerin (GTN)-mediated dilation] using high-resolution ultrasound. Carotid IMT was also measured. RESULTS: Participants were grouped as Glu-homozygotes (n = 38) and Asp-carriers (n = 62). On univariate analysis, a higher response to GTN was associated with lower brachial baseline diameter (P < 0.001) and increasing value of high-density lipoprotein cholesterol (P = 0.04) in Asp-carriers, but not in Glu-homozygotes. Higher FMD correlated with lower brachial baseline diameter (P < 0.001), BMI (P = 0.03) and SBP (P = 0.03) in the Asp-carriers, but not in Glu-homozygotes. Higher IMT showed a similar Asp-genotype-dependent association with higher BMI (P = 0.001), SBP (P = 0.006) and DBP (P = 0.001). In individuals with Asp-alleles, the multivariate analysis showed that BMI was the only independent predictor of IMT. CONCLUSION: Weight is independently associated with impaired arterial structure in healthy and genetically predisposed young individuals. The allelic variation (Asp298) of the eNOS gene polymorphism makes individuals vulnerable to the impact of weight on the development of atherosclerosis.

A novel LMNA mutation (R189W) in familial dilated cardiomyopathy: evidence for a 'hot spot' region at exon 3: a case report.

We describe a case of a patient with idiopathic dilated cardiomyopathy and cardiac conduction abnormalities who presented a strong family history of sudden cardiac death. Genetic screening of lamin A/C gene revealed in proband the presence of a novel missense mutation (R189W), near the most prevalent lamin A/C mutation (R190W), suggesting a "hot spot" region at exon 3.

Glutathione S-transferase T1- and M1-null genotypes and coronary artery disease risk in patients with Type 2 diabetes mellitus.

INTRODUCTION: Since long-term exposure to oxidative stress is strongly implicated in the pathogenesis of diabetic complications, polymorphic genes of detoxifying enzymes must be involved in the development of coronary artery disease (CAD). We assessed the potential glutathione S-transferase (GST) gene-gene (GSTM1(null)-GSTT1(null)) and gene-smoking interactions on the development of CAD in patients with Type 2 diabetes. MATERIALS & METHODS: In a case-only design, we enrolled 231 patients with Type 2 diabetes (147 male, 66.1 +/- 9.7 years) referred to our institute for coronary angiography investigation. CAD was diagnosed if there was over 50% obstruction of one or more major vessels. RESULTS: Coronary angiography revealed significant CAD in 184 patients (80%). Male gender (p < 0.001), smoking habits (p = 0.003) and GSTT1(null) genotype (p = 0.003) were significantly correlated with the increasing extent of the coronary atherosclerosis. Case-only analysis revealed that patients with both M(null)-T(null) genotypes had the highest risk for 3-vessel CAD compared with patients who express both GST genes (odds ratio: 3.1; 95% confidence interval: 1.0-10.3, p = 0.04). A nearly threefold interaction existed between cigarette smoking and M(null)-T(null) genotypes (odds ratio: 2.9, 95% confidence interval: 1.7-7.8, p = 0.03). A significant interaction between M(null)-T(null) genotypes and smoking was also observed on the increasing number of coronary vessels that were diseased (chi(2) = 14.0; p = 0.03). CONCLUSION: These data suggest that polymorphisms in GSTM1 and GSTT1 genes are risk factors for CAD in Type 2 diabetic patients, especially among smokers. These genetic markers may permit the targeting of preventive and early intervention on high-risk patients to reduce their cardiovascular risk.

Biological features (inflammation and neoangiogenesis) and atherosclerotic risk factors in carotid plaques and calcified aortic valve stenosis: two different sites of the same disease?

Neoangiogenesis and inflammation have a pivotal role in atherosclerosis. Observations support the hypothesis that calcified aortic valve stenosis is an inflammatory process, similar to atherosclerosis in tissue features and risk factors. We studied 2 groups of cases: 47 were affected by hemodynamic atherosclerotic carotid plaque (group 1) and 35 by severe calcified aortic valve stenosis (group 2). We compared the groups for atherosclerosis risk factors, morphologic features, and immunohistochemical phenotypes. In both groups, men, smokers, and hypertensive subjects prevailed, and histologic analysis showed an elevated score for T-lymphocyte infiltrates, neoangiogenesis, calcium, and sclerosis. Adhesion molecule expression was present in both lesions. Expression of intercellular adhesion molecule 1 correlated with inflammatory infiltrates (group 1, P = .0007; group 2, P = .06). Neoangiogenesis also correlated with inflammatory infiltrates (group 1, P = .035; group 2, P = .045). In valves, neoangiogenesis correlated with calcium (P = .048). Carotid plaque and calcified valve stenosis showed common risk factors and biologic hallmarks of a chronic inflammatory process. Inflammation and neoangiogenesis have a crucial role in plaque evolution and in the progression of aortic valve stenosis.

ET-1 Lys198Asn and ET(A) receptor H323H polymorphisms in heart failure. A case-control study.

BACKGROUND: The endothelin (ET) system plays a central role in the control of myocardial function and its pathophysiology. The aim of the present study was to explore whether genetic variations of ET-1 (G/T substitution that predicts an Lys/Asn change at codon 198) and its receptor ET(A) (T/C in exon 6, H323H) could predispose carriers to heart failure (HF). METHODS: Genotyping at these two loci was done in 122 patients with HF [echocardiographic left ventricular ejection fraction (LVEF) < or =40%] and 216 age-matched subjects without HF. Causes of HF included ischemic (n = 96) and idiopathic cardiomyopathies (n = 26). RESULTS: The ET-1 Lys198Asn was significantly associated with the occurrence of HF (p = 0.005). The risk of HF was independently increased among Asn/Asn in comparison to Lys carriers (OR = 3.2, p = 0.03). Moreover, homozygous carriers of both ET-1 and ET(A) variants showed a marked increase in the risk of HF (adjusted OR = 8.6, p = 0.005), displayed significantly lower LVEF (p = 0.002) and higher left ventricular end-diastolic (p = 0.03) and end-systolic diameters (p = 0.04; for Asn/Asn and TT vs. Lys and C carriers of the ET-1 and ET(A )polymorphisms, respectively). Furthermore, the extent of coronary artery disease (r = -0.62, p < 0.0001) and the Asn/Asn and TT double genotype (r = -0.30, p = 0.0001) were the only significant and independent predictors of LVEF by multivariate analysis. CONCLUSIONS: The ET-1 Lys198Asn and ET(A) receptor H323H polymorphisms seem to act synergistically to increase the risk of HF.

Platelet activation predicts recurrent ischemic events after percutaneous coronary angioplasty: a 6 months prospective study.

INTRODUCTION: An increasing amount of evidence indicates that platelet reactivity, despite a standard anti-thrombotic therapy, is a potential risk factor for recurrent myocardial ischemia in patients with coronary artery disease. We now hypothesize that this condition, measured by collagen-epinephrine (CEPI) or collagen-ADP (CADP) closure times (CT) by Platelet Function Analyzer (PFA-100), may predict the recurrence of coronary events after percutaneous coronary intervention (PCI). MATERIALS AND METHODS: CEPI and CADP-CT were measured 30+/-8 h after PCI in 175 consecutive patients admitted with a diagnosis of stable angina (n=94) or acute coronary syndromes (n=81) and prospectively followed up for a mean period of 6 months. We stratified the patients in accordance to both the CEPI-CT ( 190 s), reflecting the intensity of cycloxygenase inhibition by aspirin and the distribution into quartiles for CADP-CT. RESULTS: CEPI-CT<190 s as well as CADP-CT<82 s were associated with a higher rate of clinical recurrence (hazard ratio 8.5, p<0.001 and 22.9, p<0.001, respectively). Multivariate analysis after adjustment for other risk factors confirmed that the lowest CADP-CT quartile significantly correlates with the risk of recurrent coronary events (hazard ratio 36.5, p<0.01), as well as CEPI-CT<190 s (hazard ratio 6.7, p=0.01). CONCLUSIONS: An enhanced platelet function after PCI when measured under high shear rates by PFA-100 is an independent predictor of a worst clinical outcome, even during a short term follow-up and may help in patients risk stratification.

AMPD1 (C34T) polymorphism and clinical outcomes in patients undergoing myocardial revascularization.

BACKGROUND: C34T variant of adenosine monophosphate deaminase 1 (AMPD1) gene has been associated with a prolonged survival in heart failure and coronary artery disease, hypothetically linked to an enhanced production of adenosine. DESIGN: Since adenosine administration is a promising approach for the prevention of the ischemia-reperfusion in myocardial revascularization, the aim of this study was to investigate whether the AMPD1 (-) allele is associated with a favorable prognosis after coronary revascularization. In addition, we assessed the association between AMPD1 polymorphism and plasma adenosine levels. METHODS: We investigated a total of 161 patients receiving coronary revascularization (70 percutaneous transluminal coronary angioplasty and 91 coronary artery bypass graft). They were investigated for a composite endpoint including recurrent angina, non-fatal MI, target vessel revascularization, heart failure and cardiac death. Plasma adenosine was also measured by high-performance liquid chromatography methods on a subset of 25 patients. RESULTS: During the follow-up period (7.0+/-0.3 months), the overall combined endpoint accounted for 17 events (10 cardiac-related deaths, 6 revascularization procedures and 1 congestive heart failure). The composite endpoint was 9.8% for AMPD1 (-) allele carriers vs. 11.5% for non-carriers (log-rank statistic, p=n.s.). In the logistic analysis only low (

Diabetes and chronic nitrate therapy as co-determinants of somatic DNA damage in patients with coronary artery disease.

Somatic DNA damage has been linked to coronary artery disease (CAD). However, whether genetic instability is linked to CAD per se or to concomitant potentially genotoxic metabolic and pharmacological factors remains still unclear. The aim of this study was to evaluate the determinants of somatic DNA damage in a large population of patients undergoing coronary angiography. A total of 278 in-hospital patients (215 men, age 61.8+/-0.7 years) were studied by using micronucleus assay (MN) in human lymphocytes, which is one of the most commonly used biomarker for somatic DNA damage. Significant CAD (>50% diameter stenosis) was present in 210 patients (179 men, age 62.3+/-0.7 years). Normal coronary arteries were observed in 68 patients (35 men, age 60.2+/-1.7 years). There were no significant differences between patients with and without CAD, but patients with multivessel disease had the highest MN levels (P=0.01). MN frequency was also found significantly higher in presence of type 2 diabetes (P<0.0001), dyslipidemia (P=0.048) and nitrate therapy (P=0.0002). A significant additive effect was also observed between diabetes and nitrate therapy (P=0.02). On multivariate logistic regression analysis, diabetes [odds ratio=6.8 (95% confidence interval, 3.2-14.5), P<0.0001] and nitrate therapy [odds ratio=2.4 (95% confidence interval, 1.3-4.7), P=0.01] remained the only significant determinants for the 50th percentile of MN (>12 per thousand). These results indicated that diabetes and, to a lesser extent, chronic nitrate therapy are major determinants of somatic DNA instability in patients with CAD. DNA damage might represent an additional pathogenetic dimension and a possible therapeutic target in the still challenging management of coronary artery disease concerning diabetics.

Detection of mtDNA with 4977 bp deletion in blood cells and atherosclerotic lesions of patients with coronary artery disease.

Recent evidence suggests that somatic mutations in nuclear and mitochondrial DNA accumulated during aging, may significantly contribute to the pathogenesis of chronic-degenerative illness such as coronary artery disease (CAD). Mitochondrial DNA with 4977 bp deletion mutation (mtDNA4977) is a common type of mtDNA alteration in humans. However, little attempt has been made to detect the presence of mtDNA4977 deletion in cells and tissues of cardiovascular patients. This study investigated the presence of mtDNA4977 in blood samples of 65 cardiovascular patients and 23 atherosclerotic plaques of human coronaries with severe atherosclerosis. Moreover, the presence of the deletion has been investigated in blood cells from 22 healthy age-matched subjects. The detection of mtDNA4977 has been performed by using a nested polymerase chain reaction (PCR) protocol and normalized to wild-type mtDNA. A significant higher incidence of mtDNA4977 was observed in CAD patients with respect to healthy subjects (26.2% versus 4.5%; P=0.03). Furthermore, the relative amount of the deletion was significantly higher in the patients compared to the control group (P=0.02). The mtDNA4977 was detected in 17 of the 65 patients blood samples (26.2%) and deletion levels ranged from 0.18 to 0.46% of the total mtDNA (mean: 0.34+/-0.02%). For what concerns atherosclerotic lesions, 5 patients (21.7%) showed the deletion ranging from 0.13 to 0.45% of the total mtDNA (mean: 0.35+/-0.06%). In both samples from patients, the incidence and the relative amount of mtDNA4977 was not significantly influenced by atherogenic risk factors and clinical parameters. The obtained results may suggest that the increase of oxidative stress in cardiovascular disease may be responsible for the accumulation of mtDNA damage in coronary artery disease patients.

C677T polymorphism of the methylenetetrahydrofolate reductase gene is a risk factor of adverse events after coronary revascularization.

BACKGROUND: A common point mutation (C677T) in the gene for 5,10-methylenetetrahydrofolate reductase (MTHFR) is associated with hyperhomocysteinemia, an independent risk factor and a strong predictor of mortality in patients with coronary artery disease (CAD). The aim of this study was to investigate whether C677T polymorphism can be a predictor of major adverse cardiac events after myocardial revascularization. METHODS: We determined MTHFR genotype in 159 patients with CAD undergoing myocardial revascularization [72 percutaneous transluminal coronary angioplasty (PTCA) and 87 coronary artery bypass graft (CABG)]. Recurrent angina, nonfatal myocardial infarction (MI), target vessel revascularization, heart failure and cardiac death were considered major adverse cardiac events that occurred after discharge from index hospitalization. RESULTS: During the follow-up (6.9+/-0.3 months, mean+/-S.E.M.), the composite endpoint accounted for 25.9%, 11.4% and 4.3% for TT, CT and CC genotype (log-rank statistic 5.2, p=0.02), respectively. Subjects with mutant TT genotype had a threefold increase of any cardiac event (hazard ratio [HR]=3.0; 95% [CI], 1.1-8.1). In multiple-variable regression Cox, predictors of events were TT genotype (HR=2.8; 95% CI, 1.01-7.62, p=0.047), low-ejection fraction<40% (HR=4.5; 95% CI, 1.62-12.6, p=0.004) and revascularization procedure (HR=6.1; 95% CI, 1.86-20.34, p=0.003). CONCLUSIONS: These data indicate that the TT genotype seems to be significantly associated with major adverse cardiac events after myocardial revascularization in CAD patients, suggesting a potential pathological influence of homocysteine in the clinical outcome.

Neoangiogenesis, T-lymphocyte infiltration, and heat shock protein-60 are biological hallmarks of an immunomediated inflammatory process in end-stage calcified aortic valve stenosis.

OBJECTIVES: We investigated the main biomolecular features in the evolution of aortic stenosis, focusing on advanced lesions. BACKGROUND: "Degenerative" aortic valve stenosis shares risk factors and inflammatory similarities with atherosclerosis. METHODS: We compared nonrheumatic stenotic aortic valves from 26 patients undergoing surgical valve replacement (group A) and 14 surgical control patients (group B). We performed semiquantitative histological and immunohistochemical analyses on valve leaflets to measure inflammation, sclerosis, calcium, neoangiogenesis, and intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) expression. We assessed heat shock protein 60 (hsp60) gene expression as an index of cellular stress and C-reactive protein, erythrocyte sedimentation rate, and fibrinogen as systemic inflammatory markers. RESULTS: In group A valves, we found a prevalence of calcium nodules surrounded by activated inflammatory infiltrates, neovessels, and abundant ICAM-1, VCAM-1, and hsp60 gene expression. Specimens from group B were negative for all of these markers, except 2 of 14 positivity for hsp60. The presence of active inflammatory infiltrates correlated with an abundance of thin neovessels (p < 0.01) and hsp60 gene expression (p = 0.01), whereas neoangiogenesis correlated with inflammation (p = 0.04), calcium (p = 0.01), and hsp60 gene expression (p = 0.04). CONCLUSIONS: "Degenerative" aortic valve stenosis appears to be a chronic inflammatory process associated with atherosclerotic risk factors. The coexistence of neoangiogenesis, T-lymphocyte infiltration, adhesion molecules, and hsp60 gene expression indicates an active immunomediated process in the final phases of the disease.

Endothelial function and carotid intima-media thickness in young healthy subjects among endothelial nitric oxide synthase Glu298-->Asp and T-786-->C polymorphisms.

BACKGROUND AND PURPOSE: To assess the role of the endothelial nitric oxide synthase (eNOS) gene variants as risk factors for early atherosclerosis, we sought to investigate whether two polymorphisms located in the exon 7 (Glu298-->Asp) and in the promoter region (T-786-->C) of the eNOS gene were associated with functional changes in the endothelium and carotid intima-media thickness (IMT). METHODS: Endothelium-dependent flow-mediated brachial artery dilation (FMD), endothelium-independent dilation response to glyceryl trinitrate (GTN), and carotid IMT were assessed by high-resolution ultrasound in 118 healthy young nonsmoker subjects (30.1+/-0.5 years) genotyped for the eNOS Glu298-->Asp and T-786-->C polymorphisms. RESULTS: Carotid IMT was inversely related to FMD by univariate analysis (r=-0.28, P=0.002) and after adjustment for possible confounders in all the subjects (P<0.01). Asp homozygotes had a significantly lower FMD than Glu carriers (Glu/Glu: 15.0%+/-1.0%, Glu/Asp: 13.3%+/-0.7%, Asp/Asp: 9.6%+/-1.6%; P=0.005), whereas FMD was unaffected by the T-786-->C variant. Neither the Glu298-->Asp nor the T-786-->C polymorphisms influenced the GTN-mediated dilation. With respect to Glu carriers, Asp/Asp genotype displayed a significantly greater carotid IMT (Glu/Glu: 0.37+/-0.01 mm, Glu/Asp: 0.35+/-0.01 mm, Asp/Asp: 0.45+/-0.03 mm; P=0.0002) and significant correlations between carotid IMT and FMD (r=-0.48, P=0.04) and between carotid IMT and resting brachial artery diameter (r=0.70, P=0.001). No difference in IMT was found across the T-786-->C genotypes. By multivariate regression analysis, Asp/Asp genotype was the only significant and independent predictor of flow-mediated brachial artery dilation (FMD) (P=0.04) and carotid intima-media thickness (IMT) (P=0.006). CONCLUSIONS: The eNOS Glu298-->Asp polymorphism may be related to early atherogenesis.

Supplemental nitric oxide and its effect on myocardial injury and function in patients undergoing cardiac surgery with extracorporeal circulation.

BACKGROUND: Cardiopulmonary bypass induces a systemic inflammatory response that may contribute to clinical morbidity. Gaseous nitric oxide at relatively low concentrations may elicit peripheral anti-inflammatory effects in addition to a reduction of pulmonary resistances. We examined the effects of 20 ppm of inhaled nitric oxide administered for 8 hours during and after cardiopulmonary bypass. METHODS AND RESULTS: Twenty-nine consecutive patients undergoing aortic valve replacement combined with aortocoronary bypass were randomly allocated to either 20 ppm of inhaled nitric oxide (n = 14) or no additional inhalatory treatment (n = 15). Blood samples for total creatine kinase, creatine kinase MB fraction, and troponin I measurements were collected at 4, 12, 24, and 48 hours postsurgery. In addition, we collected perioperative blood samples for measurements of circulating nitric oxide by-products and brain natriuretic peptide. Soluble P-selectin was analyzed in blood samples withdrawn from the coronary sinus before and after aortic clamping. The area under the curve of creatine kinase MB fraction (P =.03), total creatine kinase (P =.04), and troponin I (P =.04) levels were significantly decreased in the nitric oxide-treated patients. Moreover, in the same group we observed blunted P-selectin and brain natriuretic peptide release (P =.01 and P =.02, respectively). Nitric oxide inhalation consistently enhanced nitric oxide metabolite levels (P =.01). CONCLUSIONS: Nitric oxide, when administered as a gas at low concentration, is able to blunt the release of markers of myocardial injury and to antagonize the left ventricular subclinical dysfunction during and immediately after cardiopulmonary bypass. The organ protection could be mediated, at least in part, by its anti-inflammatory properties.

A possible cardioprotective effect of heat shock proteins during cardiac surgery in pediatric patients.

BACKGROUND: Overexpression of heat shock proteins (Hsps) is associated to myocardial protection and it has been suggested that they could be a marker of cardiac preservation in conditions such as extracorporeal circulation. Aim of this study was to evaluate if cardioplegic arrest can modify the expression of Hsps in the heart and if this alteration is associated to cardiac preservation. METHOD: The levels of Hsp 27, Hsp 60, and both the constitutive and the inducible form of Hsp 70 were measured in the cardiac tissue from right atrium of pediatric patients before and after aortic cross-clamping (ACC) during cardiopulmonary bypass surgery for correction of congenital heart disease (n=20). The quantitative evaluation of Hsps was made by Western blotting analysis after tissue extraction and protein separation. Hsp 72 mRNA expression was also evaluated in pre- and post-ACC samples of eight subjects by semiquantitative RT-PCR. Peripheral levels of Troponin I, Myoglobin, LDH, CK, CK-MB were measured in basal conditions and at 12 and 24h after cardiosurgery as markers of heart damage. RESULTS: The cardioplegic arrest did not significantly modify the mean levels of all the Hsps measured. Hsp 72 levels increased after cardioplegia in the 40% of the patients and all Hsps in the 28% of subjects. The patients whose levels of Hsps are increased after cardioplegia are associated with lower post-surgery concentrations of all the markers of cardiac injury. CONCLUSIONS: This observation suggests a relationship between the increase of Hsps and the reduction of cardiac injury.

Genetic polymorphisms in folate and homocysteine metabolism as risk factors for DNA damage.

Epidemiological studies indicated a role for polymorphisms in genes of folate and homocysteine (Hcy) metabolism in the etiology of neurodegenerative disease, congenital defects and coronary artery disease (CAD). This study investigated the effect of several polymorphisms [C677 T, A1298C of methylenetetrahydrofolate reductase (MTHFR) and A66G of methionine synthase reductase (MTRR) genes] on Hcy levels and DNA damage in 68 patients who underwent coronary angiography. Plasma Hcy concentrations were higher in patients with multivessel disease with respect to monovessel disease and no-CAD patients (19.4+/-2.6 vs 11.6+/-1.2 and 13.7+/-1.4 micromol/l, respectively; P=0.03). 677TT patients had higher Hcy levels than those with 677CC or 677CT genotypes (26.2+/-4.3 vs 13.1+/-1.4 and 13.0+/-1.4 micromol/l, respectively; P=0.0006). No significant associations were found between A1298C and A66G polymorphisms and plasma Hcy levels. Among patients with 677CC genotype, 66GG individuals tended to have higher levels of Hcy than 66AA homozygotes (14.5+/-1.9 vs 8.9+/-0.7 micromol/l, P=0.06). Multivessel disease patients showed an increased frequency of DNA damage, measured by the micronucleus (MN) frequency, as compared to monovessel disease and no-CAD subjects (12.5+/-1.1 vs 8.5+/-0.8 and 8.2+/-0.9, respectively; P=0.006). The MN were positively correlated with Hcy levels (r=0.33, P=0.006) and were significantly higher in subjects with the 677TT genotype compared with the 677CC or 677CT genotypes (14.4+/-2.0 vs 8.8+/-1.2 and 9.5+/-0.7, respectively; P=0.006). A1298C and A66G polymorphisms had no effect on MN frequency. However, among 677TT patients, 66GG subjects tended to have higher levels of MN than those 66AG and 66AA (18.2+/-3.6 vs 13.8+/-4.0 and 10.3+/-1.7, respectively; P=NS). Our results indicate that genetic instability may be associated with increased risk for multiple Hcy-related diseases.

Interactive effect of the glutathione S-transferase genes and cigarette smoking on occurrence and severity of coronary artery risk.

Cardiovascular diseases and cancer are the main causes of death in developed countries. Mortality trends for these diseases suggest that they share common pathogenetic mechanisms. Glutathione S-transferase (GST) is a family of enzymes that detoxify reactive electrophiles, particularly present in tobacco smoke. Glutathione S-transferase null M1 and T1 (GSTM1 and GSTT1) genotypes have often been associated with increased risk of developing cancer. Our hypothesis was that the polymorphic GSTM1 and GSTT1 genes modulate the risk of smoking-coronary artery disease (CAD). We evaluated the distribution of GST genotypes in 430 angiographically defined patients (308 CAD and 122 non-CAD). The frequencies of GST null genotypes did not differ significantly between patients with CAD and without CAD. However, smokers with GSTM1 and GSTT1 null genotypes had a significantly higher risk of CAD than never-smokers with these genotypes present (OR 2.2 and 3.4 for smokers with null GSTM1 and GSTT1 genes, respectively). There was also evidence of multiple interaction between GSTM1 and GSTT1 deleted genotypes and smoking. In nonsmokers carrying both null genotypes the risk of CAD was 0.66. In smokers with both present genotypes the OR was 1.5 and was significantly increased in smokers with concurrent lack for GSTM1 and GSTT1 genes (OR=4.0). Moreover, smokers lacking GST genes had both more stenosed vessels and a higher Duke score than smokers expressing the genes. We also examined the levels of DNA damage in 66 men patients using the micronucleus test, a sensitive assay for evaluating chromosome damage. Micronucleus levels were higher in smokers with null genes than in smokers with present genes. These observations suggest that GST-null genotypes strengthen the effect of smoking on CAD risk by modulating the detoxification of genotoxic atherogens.