RESUMO
Protein expression profiling in the serum is used to identify novel biomarkers and investigate the signaling pathways in various diseases. The aim of the present study was to evaluate serum biomarkers associated with coronary artery stenosis resulting from atherosclerosis. The study included 4 groups of subjects: group A and B with and without coronary lesions, respectively, were selected from a previously reported cohort study on coronary atherosclerosis, control group C comprised of asymptomatic subjects and group D was used for independent validation of the microarray data by ELISA. Labeled serum proteins were profiled by an Explorer antibody array, which included 656 specific antibodies in two replicates (FullMoon Biosystems, USA). Cadherin-P, interleukin-5, glutathione S-transferase Mu, and neuronal nitric oxide synthase were sex-independently increased in Group A compared with those in group B. The microarray data on cadherin-P were externally validated in an independent group D using ELISA. Fibroblast growth factor-1, FGF-2, collagen II, granulocyte-macrophage colony-stimulating factor, IL-1 alpha, angiopoietin-2, granulocyte colony-stimulating factor, lymphocyte cell-specific protein tyrosine kinase, and IkappaB kinase b were increase in men in group A compared with group B. Cyclin-dependent kinase 1, DNA fragmentation factor subunit alpha DFF45/ICAD, adenovirus type 2 E1A, calponin, ADP-ribosylation factor-6, muscle-specific actin, thyroid hormone receptor alpha, and alpha-methylacyl-CoA racemase were specifically increased in women in Group A compared with group B. Alterations in the levels of specific proteins may point to the signaling pathways contributing to coronary atherosclerosis, and these proteins will be useful biomarkers for the progression of cardiovascular diseases.
Assuntos
Doença da Artéria Coronariana , Estenose Coronária , Fatores de Ribosilação do ADP , Actinas , Angiopoietina-2 , Anticorpos , Biomarcadores , Proteína Quinase CDC2 , Caderinas , Estudos de Coortes , Feminino , Fator 1 de Crescimento de Fibroblastos , Fator 2 de Crescimento de Fibroblastos , Glutationa Transferase , Fator Estimulador de Colônias de Granulócitos , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Humanos , Quinase I-kappa B , Interleucina-1alfa , Interleucina-5 , Masculino , Óxido Nítrico Sintase Tipo I , Proteínas Tirosina Quinases , Receptores dos Hormônios TireóideosRESUMO
BACKGROUND: Nitric oxide (NO) is one of the key regulators of vascular function. Abnormal NO signalling is linked to various cardiovascular diseases. We studied associations between circulating levels of NO metabolites, nitrite and nitrate (NOx) and total and cardiovascular mortality in a prospective 8-year follow-up cohort study in 1869 patients aged over 55 years. MATERIALS AND METHODS: The Cox proportional hazard ratio (HR) regression models were adjusted for multiple risk-related variables. Post hoc Kaplan-Meier survival curves were compared by the Log-rank test. RESULTS: Proportional Cox regression analysis demonstrated that high serum levels of NOx over 70 µmol/L were associated with elevated total mortality (HR 1.4; 95% CI: 1.06-1.80; P = 0.02) and cardiovascular mortality (HR 1.4; 95% CI: 0.98-1.98; P = 0.03) when HR was adjusted for age, sex, smoking and urinary creatinine. Additional adjustments for various mortality-associated baseline comorbidities did not influence associations of elevated NOx with total and cardiovascular mortality. Association of elevated NOx with total mortality persisted in the multivariate regression model combining a number of other characteristics while association of NOx with cardiovascular mortality became non-significant in the multivariate model. Specific subset of patients contributing to these associations was determined by Kaplan-Meier survival analysis indicating that cardiovascular and total mortality were increased in men with high serum levels of NOx over 70 µmol/L (Log-rank test P = 0.01). These associations were not observed in women. CONCLUSION: Elevated concentrations of serum NOx over 70 µmol/L can be used to predict mortality in men over 55 years of age.
Assuntos
Doenças Cardiovasculares/mortalidade , Nitratos/metabolismo , Óxido Nítrico/metabolismo , Nitritos/metabolismo , Idoso , Doenças Cardiovasculares/sangue , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Moscou/epidemiologia , Estudos Prospectivos , Fatores de RiscoRESUMO
OBJECTIVE: PBR characterizes penetration of red blood cells inside glycocalyx and its thickness can have profound impact on microcirculation and other vascular parameters. The goal of our study was to reliably quantify PBR and assess its potential use as a new marker of cardiovascular pathology. METHODS: The study included 208 patients (123 men and 85 women from 40 to 65 years of age) with various grades of cardiovascular SCORE risk index and IHD. PBR was quantified by sidestream dark field capillaroscopy with green light excitation. Cutaneous microcirculation was evaluated with laser Doppler fluorometry. RESULTS: Elevated PBR values over 2 mm were associated with morphological and functional lesions of arterial wall and microcirculation and lowered levels of ApoA1 lipoprotein. Moreover, elevated PBR values were associated with 2.07-fold increase in prevalence of cerebral atherosclerosis (P = .015) and 2.42-fold increase in prevalence of IHD (P = .024). Increase in PBR was associated with elevated systolic blood pressure. CONCLUSIONS: Thus, PBR can be considered a new highly reproducible and promising marker candidate for non-invasive diagnostics of IHD and cerebral atherosclerosis suggesting important role of microcirculation in development and progression of cardiovascular diseases.
Assuntos
Endotélio Vascular/patologia , Glicocálix/patologia , Microvasos/patologia , Isquemia Miocárdica/diagnóstico , Adulto , Idoso , Doenças Cardiovasculares/fisiopatologia , Feminino , Humanos , Arteriosclerose Intracraniana/diagnóstico , Masculino , Microcirculação , Pessoa de Meia-Idade , PrevalênciaRESUMO
OBJECTIVE: Noninvasive diagnostics of early stages of coronary artery disease and discrimination between various extents of vascular lesions in patients is an important clinical problem especially considering wide spread use of cholesterol lowering drugs that affect lipid and lipoprotein profiling. The main goal of our study was to evaluate applicability of new combinations of noninvasive biomarkers such as leptin to insulin and adiponectin to endothelin ratios, for detection of early stages of coronary atherosclerosis versus later stages of the disease. PATIENTS AND METHODS: A number of previously validated serum biomarkers were tested in a group of 500 patients with coronary artery disease and examined for their association with severity of coronary lesion according to Gensini score determined by coronary angiography. RESULTS: Lowest extent of coronary lesions was associated with significant increase in apoA-I levels and with significantly increased ratios of adiponectin to endothelin and leptin to insulin. In male but not in female patients, adiponectin to endothelin ratio below 7.0 was associated with Gensini score representing early to high coronary lesions (p = 0.02). In female but not in male patients, leptin to insulin ratio below 3.5 was associated with Gensini score representing early to high coronary lesions (p = 0.013). CONCLUSION: Leptin to insulin and adiponectin to endothelin ratios are novel derived biomarkers useful for noninvasive diagnostics of initial stages of coronary lesions in patients with coronary artery disease.
Assuntos
Adiponectina/sangue , Doença da Artéria Coronariana/diagnóstico , Endotelinas/sangue , Insulina/sangue , Leptina/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/patologia , Diagnóstico Precoce , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Fatores SexuaisRESUMO
Supraphysiological mechanical stretching in smooth muscle results in decreased contractile activity. However, the mechanism is unclear. Previous studies indicated that intestinal motility dysfunction after edema development is associated with increased smooth muscle stress and decreased myosin light chain (MLC) phosphorylation in vivo, providing an ideal model for studying mechanical stress-mediated decrease in smooth muscle contraction. Primary human intestinal smooth muscle cells (hISMCs) were subjected to either control cyclical stretch (CCS) or edema (increasing) cyclical stretch (ECS), mimicking the biophysical forces in non-edematous and edematous intestinal smooth muscle in vivo. ECS induced significant decreases in phosphorylation of MLC and MLC phosphatase targeting subunit (MYPT1) and a significant increase in p21-activated kinase (PAK) activity compared with CCS. PAK regulated MLC phosphorylation in an activity-dependent biphasic manner. PAK activation increased MLC and MYPT1 phosphorylation in CCS but decreased MLC and MYPT1 phosphorylation in hISMCs subjected to ECS. PAK inhibition had the opposite results. siRNA studies showed that PAK1 plays a critical role in regulating MLC phosphorylation in hISMCs. PAK1 enhanced MLC phosphorylation via phosphorylating MYPT1 on Thr-696, whereas PAK1 inhibited MLC phosphorylation via decreasing MYPT1 on both Thr-696 and Thr-853. Importantly, in vivo data indicated that PAK activity increased in edematous tissue, and inhibition of PAK in edematous intestine improved intestinal motility. We conclude that PAK1 positively regulates MLC phosphorylation in intestinal smooth muscle through increasing inhibitory phosphorylation of MYPT1 under physiologic conditions, whereas PAK1 negatively regulates MLC phosphorylation via inhibiting MYPT1 phosphorylation when PAK activity is increased under pathologic conditions.
Assuntos
Motilidade Gastrointestinal , Intestinos/fisiologia , Músculo Liso/fisiologia , Cadeias Leves de Miosina/metabolismo , Quinases Ativadas por p21/metabolismo , Animais , Células Cultivadas , Humanos , Masculino , Contração Muscular , Fosforilação , Ratos , Ratos Sprague-DawleyRESUMO
Malignant glioma is the most common and deadly brain tumor. A marked reduction in the levels of sGC (soluble guanylyl cyclase) transcript in the human glioma specimens has been revealed in our previous studies. In the present study, restoring the expression of sGCß1 alone repressed the aggressive course of glioma. The antitumor effect of sGCß1 was not associated with enzymatic activity of sGC since overexpression of sGCß1 alone did not influence the level of cyclic GMP. Additionally, sGCß1-induced inhibition of the growth of glioma cells was not influenced by treatment with sGC stimulators or inhibitors. The present study is the first to reveal that sGCß1 migrated into the nucleus and interacted with the promoter of the TP53 gene. Transcriptional responses induced by sGCß1 caused the G0 cell cycle arrest of glioblastoma cells and inhibition of tumor aggressiveness. sGCß1 overexpression impacted signaling in glioblastoma multiforme, including the promotion of nuclear accumulation of p53, a marked reduction in CDK6, and a significant decrease in integrin α6. These anticancer targets of sGCß1 may represent clinically important regulatory pathways that contribute to the development of a therapeutic strategy for cancer treatment.
RESUMO
The present case-control study aimed to assess associations of routine and experimental biomarkers with risk for cardiovascular death and acute myocardial infarction (AMI) in a cohort recruited from the multicenter study "Cardiovascular Epidemiology in Russian Federation" (ESSE-RF) to identify experimental biomarkers potentially suitable for expanded evaluation. A total of 222 subjects included cardiovascular death (N = 48) and AMI cases (N = 63) during 6.5-year follow up and matched healthy controls. Seven routine and eight experimental biomarkers were assayed to analyze associations with outcomes using logistic and Cox proportional hazard regressions. Elevated levels of cardiac troponin I (cTnI), C-reactive protein (CRP), and nitric oxide metabolites (NOx) were independently associated (P < 0.001) with higher risk of cardiovascular death (estimated hazard ratio (eHR) = 1.83-3.74). Elevated levels of NOx and cTnI were independently (P < 0.001) associated with higher risk of nonfatal AMI (eHRs = 1.78-2.67). Elevated levels of angiopoietin-like protein 3 (ANGPTL3) were independently associated (P < 0.001) with lower risk of cardiovascular death (eHRs 0.09-0.16) and higher risk of nonfatal AMI (eHR = 2.07; P = 0.01). These results indicated that subsequent expanded validation should focus on predictive impact of cTnI, NOx, CRP, and ANGPTL3 to develop nationwide recommendations for individual stratification of patients with cardiovascular risks.
Assuntos
Infarto do Miocárdio , Óxido Nítrico , Humanos , Seguimentos , Infarto do Miocárdio/epidemiologia , Troponina I , Biomarcadores , Prognóstico , Estudos de Casos e Controles , Proteína C-Reativa/metabolismo , Proteínas Semelhantes a AngiopoietinaRESUMO
The NO and cGMP signaling pathways are of broad physiological and pathological significance. We compared the NO/soluble guanylyl cyclase (sGC)/cGMP pathway in human glioma tissues and cell lines with that of healthy control samples and demonstrated that sGC expression is significantly lower in glioma preparations. Our analysis of GEO databases (National Cancer Institute) further revealed a statistically significant reduction of sGC transcript levels in human glioma specimens. On the other hand, the expression levels of particulate (membrane) guanylyl cyclases (pGC) and cGMP-specific phosphodiesterase (PDE) were intact in the glioma cells that we have tested. Pharmacologically manipulating endogenous cGMP generation in glioma cells through either stimulating pGC by ANP/BNP, or blocking PDE by 3-isobutyl-1-methylxanthine/zaprinast caused significant inhibition of proliferation and colony formation of glioma cells. Genetically restoring sGC expression also correlated inversely with glioma cells growth. Orthotopic implantation of glioma cells transfected with an active mutant form of sGC (sGCα1ß1(Cys105)) in athymic mice increased the survival time by 4-fold over the control. Histological analysis of xenografts overexpressing α1ß1(Cys105) sGC revealed changes in cellular architecture that resemble the morphology of normal cells. In addition, a decrease in angiogenesis contributed to glioma inhibition by sGC/cGMP therapy. Our study proposes the new concept that suppressed expression of sGC, a key enzyme in the NO/cGMP pathway, may be associated with an aggressive course of glioma. The sGC/cGMP signaling-targeted therapy may be a favorable alternative to chemotherapy and radiotherapy for glioma and perhaps other tumors.
Assuntos
Antineoplásicos/metabolismo , Regulação Enzimológica da Expressão Gênica , Glioma/enzimologia , Glioma/prevenção & controle , Guanilato Ciclase/biossíntese , Receptores Citoplasmáticos e Nucleares/biossíntese , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Glioma/patologia , Guanilato Ciclase/fisiologia , Humanos , Camundongos , Camundongos Nus , Invasividade Neoplásica/patologia , Invasividade Neoplásica/prevenção & controle , Receptores Citoplasmáticos e Nucleares/fisiologia , Guanilil Ciclase Solúvel , Ensaios Antitumorais Modelo de Xenoenxerto/métodosRESUMO
Acute secretory diarrhea induced by infection with enterotoxigenic strains of Escherichia coli involves binding of stable toxin (STa) to its receptor on the intestinal brush border, guanylyl cyclase type C (GC-C). Intracellular cGMP is elevated, inducing increase in chloride efflux and subsequent accumulation of fluid in the intestinal lumen. We have screened a library of compounds and identified a pyridopyrimidine derivatives {5-(3-bromophenyl)-1,3-dimethyl-5,11-dihydro-1H-indeno[2',1':5,6]pyrido[2,3-d]pyrimidine-2,4,6-trione; BPIPP} as an inhibitor of GC-C that can suppress STa-stimulated cGMP accumulation by decreasing GC-C activation in intact T84 human colorectal carcinoma cells. BPIPP inhibited stimulation of guanylyl cyclases, including types A and B and soluble isoform in various cells. BPIPP suppressed stimulation of adenylyl cyclase and significantly decreased the activities of adenylyl cyclase toxin of Bordetella pertussis and edema toxin of Bacillus anthracis. The effects of BPIPP on cyclic nucleotide synthesis were observed only in intact cells. The mechanism of BPIPP-dependent inhibition appears to be complex and indirect, possibly associated with phospholipase C and tyrosine-specific phosphorylation. BPIPP inhibited chloride-ion transport stimulated by activation of guanylyl or adenylyl cyclases and suppressed STa-induced fluid accumulation in an in vivo rabbit intestinal loop model. Thus, BPIPP may be a promising lead compound for treatment of diarrhea and other diseases.
Assuntos
Inibidores de Adenilil Ciclases , Antidiarreicos/química , Antidiarreicos/farmacologia , Diarreia/tratamento farmacológico , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Guanilato Ciclase/antagonistas & inibidores , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Animais , Antidiarreicos/uso terapêutico , Toxinas Bacterianas/farmacologia , Linhagem Celular , Cricetinae , AMP Cíclico/antagonistas & inibidores , AMP Cíclico/biossíntese , GMP Cíclico/antagonistas & inibidores , GMP Cíclico/biossíntese , Diarreia/enzimologia , Enterotoxinas/farmacologia , Inibidores Enzimáticos/uso terapêutico , Proteínas de Escherichia coli , Compostos Heterocíclicos de 4 ou mais Anéis/uso terapêutico , Humanos , Ratos , Bibliotecas de Moléculas PequenasRESUMO
Nitric oxide (NO) is involved in number of physiological and pathological events. Our previous studies demonstrated a differential expression of NO signaling components in mouse and human ES cells. Here, we demonstrate the effect of NO donors and soluble guanylyl cyclase (sGC) activators in differentiation of ES cells into myocardial cells. Our results with mouse and human ES cells demonstrate an increase in Nkx2.5 and myosin light chain (MLC2) mRNA expression on exposure of cells to NO donors and a decrease in mRNA expression of both cardiac-specific genes with nonspecific NOS inhibitor and a concomitant increase and decrease in the mRNA levels of sGC alpha(1) subunit. Although sGC activators alone exhibited an increase in mRNA expression of cardiac genes (MLC2 and Nkx2.5), robust inductions of mRNA and protein expression of marker genes were observed when NO donors and sGC activators were combined. Measurement of NO metabolites revealed an increase in the nitrite levels in the conditioned media and cell lysates on exposure of cells to the different concentrations of NO donors. cGMP analysis in undifferentiated stem cells revealed a lack of stimulation with NO donors. Differentiated cells however, acquired the ability to be stimulated by NO donors. Although, 3-(4-amino-5-cyclopropylpyrimidin-2-yl)-1-(2-fluorobenzyl)-1H-pyrazolo [3,4-b]pyridine (BAY 41-2272) alone was able to stimulate cGMP accumulation, the combination of NO donors and BAY 41-2272 stimulated cGMP levels more than either of the agents separately. These studies demonstrate that cGMP-mediated NO signaling plays an important role in the differentiation of ES cells into myocardial cells.
Assuntos
Diferenciação Celular/fisiologia , Células-Tronco Embrionárias/fisiologia , Miócitos Cardíacos/fisiologia , Óxido Nítrico/metabolismo , Transdução de Sinais/fisiologia , Animais , Linhagem Celular , GMP Cíclico/metabolismo , Células-Tronco Embrionárias/citologia , Guanilato Ciclase/metabolismo , Humanos , Camundongos , Miócitos Cardíacos/citologia , NG-Nitroarginina Metil Éster/metabolismo , Doadores de Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Compostos Nitrosos/metabolismo , Pirazóis/metabolismo , Piridinas/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Guanilil Ciclase SolúvelRESUMO
Our previous studies demonstrate a differential expression of nitric oxide (NO) signaling components in ES cells and our recent study demonstrated an enhanced differentiation of ES cells into myocardial cells with NO donors and soluble guanylyl cyclase (sGC) activators. Since NO-cGMP pathway exhibits a diverse role in cancer, we were interested in evaluating the role of the NO-receptor sGC and other components of the pathway in regulation of the tumor cell proliferation. Our results demonstrate a differential expression of the sGC subunits, NOS-1 and PKG mRNA and protein levels in various human cancer models. In contrast to sGC alpha(1), robust levels of sGC beta(1) were observed in OVCAR-3 (ovarian) and MDA-MB-468 (breast) cancer cells which correlated well with the sGC activity and a marked increase in cGMP levels upon exposure to the combination of a NO donor and a sGC activator. NOC-18 (DETA NONOate; NO donor), BAY41-2272 (3-(4-amino-5-cyclopropylpyrimidin-2-yl)-1-(2-fluorobenzyl)-1H-pyrazolo[3,4-b]pyridine); sGC activator), NOC-18+BAY41-2272, IBMX (3-isobutyl-1-methylxanthine; phosphodiesterase inhibitor) and 8-bromo-cGMP (cGMP analog) caused growth inhibition and apoptosis in various cancer cell lines. To elucidate the molecular mechanisms involved in growth inhibition, we evaluated the effect of activators/inhibitors on ERK phosphorylation. Our studies indicate that BAY41-2272 or the combination NOC-18+BAY41-2272 caused inhibition of the basal ERK1/2 phosphorylation in OVCAR-3 (high sGC activity), SK-OV-3 and SK-Br-3 (low sGC activity) cell lines and in some cases the inhibition was rescued by the sGC inhibitor ODQ (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one). These studies suggest that the effects of activators/inhibitors of NO-sGC-cGMP in tumor cell proliferation is mediated by both cGMP-dependent and independent mechanisms.
Assuntos
GMP Cíclico/metabolismo , Guanilato Ciclase/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Transdução de Sinais , 1-Metil-3-Isobutilxantina/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , GMP Cíclico/análogos & derivados , GMP Cíclico/farmacologia , Inibidores Enzimáticos/farmacologia , Humanos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neoplasias/enzimologia , Óxido Nítrico/metabolismo , Compostos Nitrosos/farmacologia , Fosforilação/efeitos dos fármacos , Pirazóis/farmacologia , Piridinas/farmacologia , Guanilil Ciclase Solúvel , Relação Estrutura-AtividadeRESUMO
BACKGROUND: Administration of L-nil, a selective inhibitor of inducible nitric oxide synthase (iNOS), improves ileus in an animal model of resuscitation induced intestinal edema. The purpose of this study was to elucidate the iNOS/nitric oxide (NO) signal transduction pathway in intestinal edema. MATERIALS AND METHODS: Male Sprague Dawley rats were divided into two groups; CONTROL and RESUS+VH (edema, 80 cc/kg normal saline (resuscitation) with mesenteric venous hypertension). iNOS mRNA and protein, iNOS activity, NO tissue levels, soluble guanylyl cyclase (sGC) expression, and cyclic guanosine monophosphate (cGMP) levels were measured. As a functional endpoint, we evaluated intestinal contractile strength and frequency in L-nil treated animals. RESULTS: Edema was associated with increased iNOS mRNA and protein expression without subsequent increases in iNOS activity or tissue NO levels. There was no significant change in sGC expression or increase in cGMP induced by edema. Administration of L-nil did not decrease edema development or preserve contractile strength, but increased contractile frequency. CONCLUSION: Hydrostatic intestinal edema is not associated with increased iNOS activity or tissue NO levels. Administration of L-nil in edema increases intestinal contractile frequency. This may represent a potential mechanism for the amelioration of ileus seen with the administration of L-nil.
Assuntos
GMP Cíclico/metabolismo , Edema/metabolismo , Motilidade Gastrointestinal , Enteropatias/enzimologia , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico/metabolismo , Animais , Guanilato Ciclase/metabolismo , Pressão Hidrostática , Imuno-Histoquímica , Lisina/análogos & derivados , Masculino , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de SinaisRESUMO
OBJECTIVES: Endothelial dysfunction contributes to the onset and progression of cardiovascular diseases. However, direct associations of vasoactive mediators with cardiovascular risk are poorly understood. METHODS: We have determined associations of circulating levels of stable metabolites of nitric oxide, nitrate and nitrite (NOx), endothelin-1, and the endothelin-1/NOx ratio with blood pressure in 177 asymptomatic subjects without signs of coronary atherosclerosis; associations with blood pressure and with presence of coronary lesions were also evaluated in 457 patients suspected to have coronary heart disease with or without coronary lesions confirmed by coronary angiography. All participants were on a low nitrate diet 24 h prior to blood sampling. RESULTS: In men, NOx levels were inversely correlated with blood pressure similar to women with low (0-4%) European Systematic Coronary Risk Estimation (SCORE). However, the correlation was not significant in women with high SCORE (5-8%). High systolic blood pressure over 140 mm Hg was negatively associated with NOx levels in asymptomatic men (p=0.05) but not in women. This association is disrupted in male and female patients with coronary atherosclerosis. In male patients, NOx (p=0.05), endothelin (p=0.01), and the endothelin/NOx ratio (p=0.04) were associated with presence of coronary lesions. CONCLUSIONS: Thus, elevated cardiovascular risk according to SCORE over 4% in asymptomatic women, but not in men, is associated with a shift in markers of endothelial dysfunction. Presence of coronary lesions in patients is associated with significant changes in circulating levels of markers of endothelial dysfunction in men but not in women.
Assuntos
Biomarcadores , Pressão Sanguínea , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/metabolismo , Endotelinas/metabolismo , Endotélio Vascular/metabolismo , Óxido Nítrico/metabolismo , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/fisiopatologia , Angiografia Coronária , Doença da Artéria Coronariana/etiologia , Doença da Artéria Coronariana/metabolismo , Suscetibilidade a Doenças , Europa (Continente) , Feminino , Fatores de Risco de Doenças Cardíacas , Humanos , Masculino , Óxido Nítrico/sangue , Fatores SexuaisRESUMO
A series of pyridopyrimidine derivatives were synthesized and evaluated for their ability to inhibit cyclic nucleotide synthesis in the presence of stable toxin a of Escherichia coli. The structure activity relationships around the basic core structure were examined and examples with better activity and potentially better pharmacological properties are presented.
Assuntos
Toxinas Bacterianas/metabolismo , GMP Cíclico/biossíntese , Enterotoxinas/metabolismo , Pirimidinas/química , Linhagem Celular Tumoral , Escherichia coli/metabolismo , Proteínas de Escherichia coli , Guanilato Ciclase/antagonistas & inibidores , Guanilato Ciclase/metabolismo , Humanos , Pirimidinas/síntese química , Pirimidinas/farmacologia , Receptores de Enterotoxina , Receptores Acoplados a Guanilato Ciclase , Receptores de Peptídeos/antagonistas & inibidores , Receptores de Peptídeos/metabolismo , Relação Estrutura-AtividadeRESUMO
Here, we review the early studies on cGMP, guanylyl cyclases, and cGMP-dependent protein kinases to facilitate understanding of development of this exciting but complex field of research encompassing pharmacology, biochemistry, physiology, and molecular biology of these important regulatory molecules.
Assuntos
Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Guanilato Ciclase/metabolismo , Animais , GMP Cíclico/história , Proteínas Quinases Dependentes de GMP Cíclico/história , Guanilato Ciclase/história , História do Século XX , Humanos , Conformação Proteica , Isoformas de Proteínas , Transdução de SinaisRESUMO
Adiponectin is encoded by the ADIPOQ gene and participates in the pathogenesis of cardiovascular and metabolic diseases. The goal of the study was to assess associations of rs17300539, rs266729, rs182052, rs2241766, and rs17366743 single nucleotide polymorphisms (SNPs) of the ADIPOQ gene with concentrations of serum adiponectin and with coronary atherosclerosis and type 2 diabetes mellitus in 447 patients (316 men and 131 women) subjected to coronary angiography. SNPs of the ADIPOQ gene of the study participants were genotyped using real-time PCR. Multivariate linear regression adjusted for covariates revealed significant association between rs182052 SNP and serum adiponectin concentration (ß= -0.11; 95% confidence interval (95%CI): -0.19, -0.03; p = 0.016). Regression analysis revealed an increase in prevalence of unstable angina (OR (odds ratio) = 2.55; 95%CI 1.4-4.82; p = 0.018) and coronary artery disease (OR = 1.55; 95%CI 1.15-2.09; p = 0.021) per copy of the rs182052 A allele. Prevalence of type 2 diabetes mellitus was higher in subjects with the rs182052 A allele (OR = 2.29; 95%CI 1.29-4.21; p = 0.024). Regression analysis of rs266729 showed that prevalence of unstable angina was increased (OR = 3.59; 95%CI 1.17-10.01; p = 0.045) in the subjects with the GG genotype and prevalence of coronary artery disease (CAD) was significantly increased (OR = 1.48; 95%CI 1.09-2.03; p = 0.045) per copy of the G allele. Haplotype analysis revealed that the subjects with the GCATT haplotype have lower adiponectin levels (ß= -0.15; p = 0.042) and higher prevalence of unstable angina (OR = 3.597; p = 0.007) compared with reference haplotype carriers. Thus, the results indicate that minor A allele of rs182052 of the ADIPOQ gene is significantly associated with a decrease in serum adiponectin levels, and two SNPs (rs182052 and rs266729) of the ADIPOQ gene are significantly associated with cardiovascular and metabolic diseases.
Assuntos
Adiponectina/metabolismo , Doença da Artéria Coronariana/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Adiponectina/sangue , Adiponectina/genética , Alelos , Estudos de Coortes , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Adiponectin, endothelin and nitric oxide (NO) are major regulators of vascular function. An imbalance of vasoactive factors contributes to the onset and progression of atherosclerosis. Various single nucleotide polymorphisms (SNPs) are considered to be risk factors for coronary heart disease. However, the molecular mechanisms of their associations with the components of endothelial dysfunction are poorly understood. In the present study, rs17366743, rs17300539, rs266729, rs182052 and rs2241766 SNPs of the adiponectin (ADIPOQ) gene and rs2070699, rs1800542 and rs1800543 SNPs of the endothelin-1 (EDN1) gene were genotyped in 477 patients with coronary heart disease who were subjected to coronary angiography, in order to determine the presence or absence of coronary atherosclerosis. The serum levels of adiponectin, endothelin and stable metabolites of NO, (nitrate and nitrite NOx), were assayed and their associations with the SNP genotypes and coronary lesions were calculated. The results indicated that rs17366743 of the ADIPOQ gene and rs2070699 and rs1800543 of the EDN1 gene were associated with the levels of NOx in women, which in turn was associated with cardiovascular mortality. In men, rs182052 and rs266729 of the ADIPOQ gene were associated with adiponectin levels, whereas rs17366743 of the ADIPOQ gene was associated with endothelin levels. Additionally, these SNPs were indirectly associated with the prevalence of coronary lesions in men. Therefore, the tested SNPs can be considered potential risk factors that lead to imbalance of vasoactive mediators in a gender-specific manner and contribute to the development of clinical manifestations of atherosclerosis.
RESUMO
Nitric oxide (NO) is an important functional regulator that contributes to progression of various cardiovascular diseases. We studied associations between nitric oxide metabolites, nitrite and nitrate (NOx), and cardiovascular mortality in a prospective 3-year follow-up cohort study in 1,869 elderly patients aged over 55 years. The Cox proportional hazard regression model was adjusted for multiple factors including sex, age, risk corresponding to preexisting cardiovascular conditions, and serum inflammatory markers (C-reactive protein, interleukin-6, fibrinogen, and leucocytes count). During the follow-up period, there were a total of 348 deaths including 216 deaths unrelated to cardiovascular events and 132 cardiovascular deaths. Cox regression adjusted for factors related to cardiovascular disease risks and inflammatory markers showed a significant association between high levels of serum nitric oxide metabolites, NOx, and increased cardiovascular mortality (hazard ratio 2.21; 95% confidence interval 1.13-4.31) but there was no association with non-cardiovascular mortality. Analysis of adjusted hazard ratios demonstrates that association of serum nitric oxide metabolites with cardiovascular mortality was independent of levels of inflammatory markers. Thus, elevated concentrations of serum nitric oxide metabolites are a predictor of cardiovascular mortality and may be used as an integral marker of cardiovascular death. © 2016 BioFactors, 43(1):82-89, 2017.
Assuntos
Doenças Cardiovasculares/sangue , Nitratos/sangue , Nitritos/sangue , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/mortalidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de RiscoRESUMO
BACKGROUND: Nitric oxide and its metabolites, nitrate and nitrite, are important regulators linked to various diseases. We studied the association of fasting serum concentrations of nitrate and nitrite, combined as NOx, without special diet, with the prevalence of various chronic diseases. METHODS: Fasting concentrations of NOx were assayed in a cohort of 1087 patients recruited to Stress Aging and Health in Russia study that represents male and female population in Moscow, Russia, over 55 years of age. Chronic diseases were recorded based on anamnesis and additional assays were run to characterize immune status and lipid and carbohydrate metabolism. Odds ratios were calculated to associate NOx concentrations with prevalence of chronic diseases in pooled deciles below or above borderline. RESULTS: NOx over 44.7 µM were associated with increased prevalence of various chronic diseases such as diabetes type II, hyperthyroidism, coronary heart disease, gout and thrombosis/stroke. NOx 65.3 µM and above were associated with lowered prevalence of osteoporosis. NOx levels of 74.6 µM and above were associated with significantly higher number of patients who abstain from consumption of alcoholic beverages. NOx were not associated with cancer. CONCLUSIONS: Thus, fasting concentrations of NOx in serum can be an important diagnostic parameter characteristic for specific chronic diseases.
Assuntos
Doença Crônica/classificação , Doença Crônica/epidemiologia , Nitratos/sangue , Óxido Nítrico/sangue , Nitritos/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Jejum , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias , Estudos Prospectivos , Análise de Regressão , Federação Russa/epidemiologiaRESUMO
The nitric oxide (NO)-cyclic GMP pathway contributes to human stem cell differentiation, but NO free radical production can also damage DNA, necessitating a robust DNA damage response (DDR) to ensure cell survival. How the DDR is affected by differentiation is unclear. Differentiation of stem cells, either inducible pluripotent or embryonic derived, increased residual DNA damage as determined by γ-H2AX and 53BP1 foci, with increased S-phase-specific chromosomal aberration after exposure to DNA-damaging agents, suggesting reduced homologous recombination (HR) repair as supported by the observation of decreased HR-related repair factor foci formation (RAD51 and BRCA1). Differentiated cells also had relatively increased fork stalling and R-loop formation after DNA replication stress. Treatment with NO donor (NOC-18), which causes stem cell differentiation has no effect on double-strand break (DSB) repair by non-homologous end-joining but reduced DSB repair by HR. Present studies suggest that DNA repair by HR is impaired in differentiated cells.