atrial-natriuretic-factor and Inflammation

Natriuretic peptide receptor A (NPR-A) is the receptor for atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP). NPR-A plays critical physiological and pathophysiological roles in several target cell and tissue system processes, such as cell growth, apoptosis, proliferation, and inflammation. Accumulating data demonstrate that NPR-A is involved in immune and inflammatory reactions and is a potential target in inflammation treatment. It is expressed in various cancer cells and is important for tumor growth. A recent study indicated that NPR-A signaling can regulate stem cell recruitment and angiogenesis. This signaling can serve as a model for studying the linkage between inflammation and tumorigenesis. In this review we highlight the mechanisms by which NPR-A affects signaling pathways involved in inflammation and cancer, and we discuss its potential as a novel target in inflammation, cancer, and cancer-related inflammation.

Topics: Apoptosis; Atrial Natriuretic Factor; Carcinogenesis; Cell Proliferation; Humans; Inflammation; Natriuretic Peptide, Brain; Neoplasms; Neovascularization, Pathologic; Receptors, Atrial Natriuretic Factor; Signal Transduction

The endocrine heart produces the polypeptide hormones Atrial Natriuretic Factor (ANF or ANP) and Brain Natriuretic Peptide (BNP). Through the peripheral actions of these hormones the heart contributes to the regulation of the cardiac preload and afterload. More recently, new functions for these hormones have been described including the modulation of the immune response. Plasma levels of BNP but not those of ANF, increase following an acute rejection episode of a cardiac allotransplant but return to levels pre-rejection with successful treatment. This observation constitutes the first observation leading to characterizing the interactions of BNP with the immune response. Several other pathologies with an inflammatory component are now known to be associated with an increase in the production of BNP. Such an increase is due to an increase in the transcriptional activity of the BNP gene induced by cytokines and related substances. In vitro investigations have shown that an increase in BNP directly modulates immunological activity. Inflammation and hemodynamic changes co-exist in several cardiovascular diseases and therefore it may be beneficial to measure circulating levels of both ANF and BNP as biomarkers of changes in intravascular volume and of changes in intravascular volume plus inflammation, respectively. Changes in plasma ANF, that are relatively larger than those of BNP, might be an indication of hemodynamic deterioration while important changes in circulating BNP could indicate a worsening of the inflammatory process.

Topics: Animals; Atrial Natriuretic Factor; Biomedical Research; Hemodynamics; Humans; Inflammation; Myocarditis; Myocytes, Cardiac; Natriuretic Peptide, Brain; Sepsis

As a continuation of "Postmortem Chemistry Update Part I," Part II deals with molecules linked to liver and cardiac functions, alcohol intake and alcohol misuse, myocardial ischemia, inflammation, sepsis, anaphylaxis, and hormonal disturbances. A very important array of new material concerning these situations had appeared in the forensic literature over the last two decades. Some molecules, such as procalcitonin and C-reactive protein, are currently researched in cases of suspected sepsis and inflammation, whereas many other analytes are not integrated into routine casework. As in part I, a literature review concerning a large panel of molecules of forensic interest is presented, as well as the results of our own observations, where possible.

Topics: Alcohol Drinking; Alcoholism; Anaphylaxis; Atrial Natriuretic Factor; Biomarkers; C-Reactive Protein; Calcitonin; Calcitonin Gene-Related Peptide; Forensic Pathology; Glucuronates; Heart Diseases; Heart Function Tests; Hormones; Humans; Inflammation; Liver; Liver Function Tests; Postmortem Changes; Protein Precursors; Sepsis; Sulfuric Acid Esters; Transferrin

Biomarkers have been intensively studied in community-acquired pneumonia (CAP) in recent years. In the context of the CAPNETZ study we had the unique opportunity to evaluate old and new biomarkers in a multicentre study with a high number of patients.. In several substudies we found the following results: procalcitonin, CRP and leukocytes show highest values in patients with typical bacterial etiology of CAP, but do not allow individual prediction of etiology. Patients without antibiotic pre-treatment show higher values of biomarkers compared to patients with antibiotic pre-treatment. New cardiovascular biomarkers are good predictors for short- and long-term mortality in CAP, superior to the inflammatory markers procalcitonin, CRP and leukocytes and at least comparable to the clinical CRB-65 score. Pro-Adrenomedullin is among the new biomarkers the one with the best prognostic value.. Biomarkers correlate with the severity of CAP but do not allow individual prediction of etiology. New cardiovascular biomarkers are suitable for the evaluation of short- and long-term prognosis in CAP. The combination of several biomarkers reflecting different pathophysiological pathways has the potential to improve management of CAP in the future.

Topics: Adolescent; Adrenomedullin; Adult; Age Distribution; Aged; Aged, 80 and over; Atrial Natriuretic Factor; Biomarkers; Blood Pressure; C-Reactive Protein; Calcitonin; Calcitonin Gene-Related Peptide; Cardiovascular Diseases; Community-Acquired Infections; Comorbidity; Endothelin-1; Female; Germany; Humans; Inflammation; Leukocyte Count; Male; Middle Aged; Pneumonia; Predictive Value of Tests; Protein Precursors; Respiratory Rate; Survival Analysis; Vasopressins; Young Adult

The natriuretic peptide system includes three known peptides: atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and C-type natriuretic peptide (CNP). They contribute to the regulation of cardiovascular homeostasis through diuretic, natriuretic, and vasodilatory properties. Among them, ANP has received particular attention because of its effects on blood pressure regulation and cardiac function. Although the potential for its therapeutic application in the treatment of hypertension and heart failure has been evaluated in several experimental and clinical investigations, no pharmacological approach directly targeted at modulation of ANP levels has ever reached the stage of being incorporated into clinical practice. Recently, ANP has also received attention as being a possible cardiovascular risk factor, particularly in the context of hypertension, stroke, obesity, and metabolic syndrome. Abnormalities in either peptide levels or peptide structure are thought to underlie its implied role in mediating cardiovascular diseases. Meanwhile, BNP has emerged as a relevant marker of left ventricular (LV) dysfunction and as a useful predictor of future outcome in patients with heart failure. This review deals with the major relevant findings related to the cardiovascular and metabolic effects of natriuretic peptides, to their potential therapeutic use, and to their role in mediating cardiovascular diseases.

Topics: Atrial Natriuretic Factor; Biomarkers; Blood Pressure; Blood Vessels; Cardiovascular Diseases; Fibrosis; Humans; Inflammation; Insulin Resistance; Lipid Metabolism; Myocardium; Natriuretic Peptide, Brain; Natriuretic Peptide, C-Type; Natriuretic Peptides; Risk Factors; Ventricular Dysfunction, Left; Ventricular Remodeling

Atrial natriuretic peptide (ANP) is a hormone predominately produced by the heart atria which regulates the water and salt balance as well as blood pressure homeostasis. Being expressed in various parts of the immune system a link of the peptide to the immune system has been proposed. In fact, this review focus on effects of ANP in the immune system and reports about the role of the peptide in innate immune functions as well as in the adaptive immune response.

Topics: Animals; Atrial Natriuretic Factor; Cell Adhesion; Cyclooxygenase 2; Humans; Immune System; Inflammation; Membrane Proteins; Models, Biological; NF-kappa B; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Prostaglandin-Endoperoxide Synthases; Tumor Necrosis Factor-alpha

Previous results have shown that inhibition of the renin-angiotensin system (RAS) either with an angiotensin II (Ang II), type 1 receptor blocker (losartan) or with an angiotensin converting enzyme inhibitor (ACEI, enalapril) has a protective effect on cardiovascular, renal, hepatic and cerebral structure and function during aging. The present study has analyzed the effect of chronic administration of a newly developed compound, omapatrilat, on clinical, histological and biochemical changes due to aging. Omapatrilat combines the action of an ACEI and of an inhibitor of a neutral endopeptidase involved in the metabolism of the atrial natriuretic peptide. The final effect is a decrease of a vasoconstrictor and proinflammatory mechanism like the RAS and the potentiation of two vasodilating compounds like bradykinin and the atrial natriuretic peptide. Based on these actions, its protective effect might be greater than formerly used pharmacological agents. Determinations have been performed on young adults (6 months old), adults (12 months old) or senile (18 months old) rats. Omapatrilat (35 mg/kg/day during 6 months and 20 mg/kg/day thereafter) was administered in the drinking water since weaning until sacrifice. Cardiovascular, renal, and cerebral structure as well as cognitive behavior, cardiovascular and renal function has been analyzed. The biochemical analysis has also established whether the beneficial action of Ang II inhibition is related to an increased activity of the nitric oxide synthase as observed in previous studies. Moreover, this study has tried to determine the relationship between the protective effect of these drugs and the levels of antioxidant defenses present in the blood and/or in the tissues. Hence, enzymatic and non-enzymatic antioxidants have been evaluated.

Topics: Aging; Angiotensin II; Angiotensin-Converting Enzyme Inhibitors; Animals; Antioxidants; Atrial Natriuretic Factor; Cardiovascular System; Cognition; Inflammation; Kidney; Nitric Oxide Synthase; Protease Inhibitors; Pyridines; Rats; Renin-Angiotensin System; Thiazepines; Vasoconstriction; Vasodilation

We have demonstrated that an increased peak serum C-reactive protein (CRP) level after acute myocardial infarction (AMI) was a major predictor of left ventricular (LV) remodeling. We sought to clarify the effect of aging on the postinfarction inflammatory response and LV remodeling.. We studied 102 patients who underwent primary angioplasty for a first anterior Q-wave AMI. Serum CRP levels, plasma neurohormones and interleukin-6 (IL-6) levels, and LV volume by left ventriculography were serially measured. Patients were divided into two groups according to their age (>or=70 years, n=33; <70 years, n=69).. There was no difference in use of cardiovascular drugs and coronary angiographic findings. Older patients had a greater increase in LV end-diastolic volume during 2 weeks after AMI (p=0.0007) and a higher peak CRP level (12.4+/-7.3 vs. 5.5+/-4.2 mg/dl, p<0.0001), although peak CK level was comparable between the two groups. Plasma atrial natriuretic peptide, brain natriuretic peptide and IL-6 levels were higher in older patients at 2 weeks and 6 months after AMI.. Augmented and prolonged activation of the inflammatory system after AMI was observed in older patients, in association with exaggerated LV remodeling. Aging may adversely affect LV remodeling through modification of the inflammatory response after AMI.

Topics: Aged; Aging; Atrial Natriuretic Factor; C-Reactive Protein; Coronary Angiography; Creatine Kinase; Electrocardiography; Humans; Inflammation; Interleukin-6; Myocardial Infarction; Myocardial Reperfusion; Natriuretic Peptide, Brain; Prospective Studies; Regression Analysis; Ventricular Function; Ventricular Remodeling

Metabolic syndrome (MetS) is a cluster of factors that increase the risk of developing diabetes, stroke, and heart failure. The pathophysiology of injury by ischemia/reperfusion (I/R) is highly complex and the inflammatory condition plays an important role by increasing matrix remodeling and cardiac apoptosis. Natriuretic peptides (NPs) are cardiac hormones with numerous beneficial effects mainly mediated by a cell surface receptor named atrial natriuretic peptide receptor (ANPr). Although NPs are powerful clinical markers of cardiac failure, their role in I/R is still controversial. Peroxisome proliferator-activated receptor α agonists exert cardiovascular therapeutic actions; however, their effect on the NPs' signaling pathway has not been extensively studied. Our study provides important insight into the regulation of both ANP and ANPr in the hearts of MetS rats and their association with the inflammatory conditions caused by damage from I/R. Moreover, we show that pre-treatment with clofibrate was able to decrease the inflammatory response that, in turn, decreases myocardial fibrosis, the expression of metalloprotease 2 and apoptosis. Treatment with clofibrate is also associated with a decrease in ANP and ANPr expression.

Topics: Animals; Arrhythmias, Cardiac; Atrial Natriuretic Factor; Clofibrate; Inflammation; Ischemia; Metabolic Syndrome; Natriuretic Peptides; PPAR alpha; Rats; Receptors, Atrial Natriuretic Factor; Reperfusion Injury

Ginkgolides are terpenoids peculiar to Ginkgo biloba, which have protective properties against cardiac diseases. This study aims to explore whether ginkgolide A (GA) could improve cardiac dysfunction of MI mice, and whether it could alleviate cardiac remodeling via binding to matrix metalloproteinase-9 (MMP9) to attenuate inflammation. Cardiac remodeling in mice induced by left coronary artery ligation were used in the in vivo model, and angiotensin (Ang) II-induced cardiac fibroblasts (NRCFs) and cardiomyocytes (NRCMs) isolated from neonatal rats were used in in vitro fibrosis and hypertrophy models, respectively. Cardiac dysfunction and fibrosis in MI mice were alleviated by GA treatment. Upregulations of collagen I (Col I), collagen III (Col III) and fibronectin in NRCFs, and enhanced levels of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and beta-myosin heavy chain (β-MHC) in NRCMs were inhibited by GA treatment. A total of 100 potential targets were found in 5 databases (TCMSP, BATMAN-TCM, PharmMapper, ETCM and SWISS Target). According to Protein Data Bank database GA could form hydrogen bonds between LYS65, GLU157, ASN17, ARG109, ARG106 of MMP9 protein, a target of GA. The regulatory role of GA in downregulating Col I, Col III, fibronectin in NRCFs, and enhancing levels of ANP, BNP and β-MHC in NRCMs were reversed by MMP9 overexpression, so as the downregulation of IL-1β, IL-6 and TNF-α in Ang II-induced NRCFs and NRCMs. GA could alleviate cardiac dysfunction and remodeling via binding to MMP9 to attenuate inflammation. Therefore, GA is a potential drug for cardiac remodeling therapy.

Topics: Angiotensin II; Animals; Atrial Natriuretic Factor; Cardiomegaly; Cardiotonic Agents; Fibronectins; Fibrosis; Ginkgolides; Heart Diseases; Inflammation; Lactones; Matrix Metalloproteinase 9; Mice; Myocardial Infarction; Myocytes, Cardiac; Rats; Ventricular Remodeling

Diabetic cardiomyopathy (DCM) is a chronic complication of diabetes that emphasizes the urgency of developing new drug therapies. With an illustrious history in traditional medicine to improve diabetes, cinnamon has been shown to possess blood lipids lowering effects and antioxidative and anti-inflammatory properties. However, the extent to which it protects the diabetic heart has yet to be determined. Forty-eight rats were administered in the study and grouped as: control; diabetic; diabetic rats given 100, 200, or 400 mg/kg cinnamon extract, metformin (300 mg/kg), valsartan (30 mg/kg), or met/val (combination of both drugs), via gavage for six weeks. Fasting blood sugar (FBS) and markers of cardiac injury including creatine kinase-muscle/brain (CK-MB), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) were evaluated in blood samples. Malondialdehyde (MDA) levels, the total contents of thiol, superoxide dismutase (SOD), and catalase (CAT) activities were measured. Histopathology study and gene expression measurement of angiotensin II type 1 receptor (AT1), atrial natriuretic peptide (ANP), beta-myosin heavy chain (β-MHC), and brain natriuretic peptide (BNP) were done on cardiac tissue. FBS and cardiac enzyme indicators were reduced in all treated groups. A reduction in MDA level and enhancement in thiol content alongside with increase of SOD and CAT activities were observed in extract groups. The decrease of inflammation and fibrosis was obvious in treated groups, notably in the high-dose extract group. Furthermore, all treated diabetic groups showed a lowering trend in AT1, ANP, β-MHC, and BNP gene expression. Cinnamon extract, in addition to its hypoglycemic and antioxidant properties, can prevent diabetic heart damage by alleviating cardiac inflammation and fibrosis. PRACTICAL APPLICATIONS: This study found that cinnamon extract might protect diabetic heart damage by reducing inflammation and fibrosis in cardiac tissue, in addition to lowering blood glucose levels and increasing antioxidant activity. Our data imply that including cinnamon in diabetic participants' diets may help to reduce risk factors of cardiovascular diseases.

Topics: Animals; Antioxidants; Atrial Natriuretic Factor; Cinnamomum zeylanicum; Diabetes Mellitus, Experimental; Diabetic Cardiomyopathies; Fibrosis; Heart Injuries; Humans; Hypertrophy; Inflammation; Plant Extracts; Rats; Sulfhydryl Compounds; Superoxide Dismutase

Inflammation, by inducing a tumor-promoting microenvironment, is a hallmark for prostate cancer (PCa) progression. NOD-like receptor protein 3 (NLRP3)-inflammasome activation, interleukin-1β (IL-1β) secretion, and cancer cell-released extracellular vesicles (EVs) contribute to the establishment of tumor microenvironment. We have shown that PC3-derived EVs (PC3-EVs) activate inflammasome cascade in non-cancerous PNT2 cells. It is known that the endogenous biomolecules and Natriuretic Peptides (NPs), such as ANP and BNP, inhibit inflammasome activation in immune cells. Here we investigated whether ANP and BNP modify PCa inflammatory phenotype in vitro. By using PNT2, LNCaP, and PC3 cell lines, which model different PCa progression stages, we analyzed inflammasome activation and the related pathways by Western blot and IL-1β secretion by ELISA. We found that tumor progression is characterized by constitutive inflammasome activation, increased IL-1β secretion, and reduced endogenous NPs expression. The administration of exogenous ANP and BNP, via p38-MAPK or ERK1/2-MAPK, by inducing NLRP3 phosphorylation, counteract inflammasome activation and IL-1β maturation in PC3 and PC3-EVs-treated PNT2 cells, respectively. Our results demonstrate that NPs, by interfering with cell-specific signaling pathways, exert pleiotropic anti-inflammatory effects converging toward inflammasome phosphorylation and suggest that NPs can be included in a drug repurposing process for PCa.

Topics: Antineoplastic Agents; Atrial Natriuretic Factor; Cell Line, Tumor; Humans; Inflammation; Male; MAP Kinase Signaling System; Natriuretic Peptide, Brain; Neoplasm Proteins; Prostatic Neoplasms

Post-traumatic stress disorder (PTSD) is related with myocardial injury and cardiac dysfunction, while the molecular mechanism has not been clear. This study investigated whether TLR4/MyD88/NF-κB-mediated inflammation involved in myocardial injury of PTSD. Adult male Wistar rats were exposed to single-prolonged stress (SPS), which was used broadly as a animal model of PTSD. Morris Water Maze (MWM) test and forced swimming test (FST) was carried out for behavioral testing. The protein expression of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) in the left ventricular of heart and TLR4/MyD88/NF-κB-mediated inflammation were examined. Our results showed that there were obvious increased in the protein expression of ANP and BNP in heart after exposure to SPS, SPS also significantly enhanced the serum level of IL-1β and TNF-α, and meanwhile, the TLR4/MyD88/NF-κB pathway were activated. These results demonstrated that the TLR4/MyD88/NF-κB pathway were involved in the myocardial injury of PTSD, which might be one of possible molecular mechanism contributed to the pathogenesis of cardiac dysfunction in PTSD.

Topics: Animals; Atrial Natriuretic Factor; Depression; Heart; Heart Ventricles; Inflammation; Interleukin-1beta; Learning; Male; Memory; Myeloid Differentiation Factor 88; Natriuretic Peptide, Brain; NF-kappa B; Rats, Wistar; Signal Transduction; Stress Disorders, Post-Traumatic; Toll-Like Receptor 4; Tumor Necrosis Factor-alpha; Up-Regulation; Vascular Remodeling

Topics: Animals; Atrial Natriuretic Factor; Bacterial Proteins; Bacterial Toxins; Caco-2 Cells; Cardiovascular Diseases; Cell Line, Tumor; Cells, Cultured; Clostridioides difficile; Clostridium Infections; Cytokines; Disease Models, Animal; Enterotoxins; Human Umbilical Vein Endothelial Cells; Humans; Inflammation; Intestines; Natriuretic Peptide, Brain; Neutrophils; Serum Albumin, Human; Vascular Endothelial Growth Factor A; Zebrafish

Current critical shortage of donor organs has increased the use of donation after circulatory death (DCD) livers for transplantation, despite higher risk for primary nonfunction or ischemic cholangiopathy. Human atrial natriuretic peptide (hANP) is a cardiovascular hormone that possesses protective action to vascular endothelia. We aimed to clarify the therapeutic potential of hANP in cold storage of DCD livers.. Male Wistar rats were exposed to 30-minute warm ischemia in situ. Livers were then retrieved and cold-preserved for 6 hours with or without hANP supplementation. Functional and morphological integrity of the livers was evaluated by oxygenated ex vivo reperfusion at 37°C.. hANP supplementation resulted in significant reduction of portal venous pressure (12.2 ± 0.5 versus 22.5 ± 3.5 mm Hg, P < 0.001). As underlying mechanisms, hANP supplementation significantly increased tissue adenosine concentration (P = 0.008), resulting in significant upregulation of endothelial nitric oxide synthase and significant downregulation of endothelin-1 (P = 0.01 and P = 0.004 vs. the controls, respectively). Consequently, hANP significantly decreased transaminase release (P < 0.001) and increased bile production (96.2 ± 18.2 versus 36.2 ± 15.2 μL/g-liver/h, P < 0.001). Morphologically, hepatocytes and sinusoidal endothelia were both better maintained by hANP (P = 0.021). Electron microscopy also revealed that sinusoidal ultrastructures and microvilli formation in bile canaliculi were both better preserved by hANP supplementation. Silver staining also demonstrated that hANP significantly preserved reticulin fibers in Disse space (P = 0.017), representing significant protection of sinusoidal frameworks/architectures.. Supplementation of hANP during cold storage significantly attenuated cold ischemia/warm reperfusion injury of DCD livers.

Topics: Adenosine Triphosphate; Animals; Anti-Inflammatory Agents; Atrial Natriuretic Factor; Bile; Bile Duct Diseases; Disease Models, Animal; Endothelium, Vascular; Humans; Inflammation; Liver; Male; Microscopy, Electron; Organ Preservation; Oxidative Stress; Oxygen; Oxygen Consumption; Perfusion; Rats; Rats, Wistar; Risk; Tissue and Organ Procurement; Warm Ischemia

We previously reported that atrial natriuretic peptide (ANP) reduces serum amylase and intrapancreatic trypsinogen activation in the onset of acute pancreatitis whereas secretin increases them. In the present work, we sought to establish the effect of ANP and secretin on the inflammatory response and cell death in experimental acute pancreatitis.. The expression and activity of key inflammatory mediators and apoptosis were evaluated in the presence or absence of the atrial peptide, secretin or both in cerulein-induced acute pancreatitis in rats. Also, ultrastructural changes in pancreatic acinar cells were assessed by transmission electron microscopy.. ANP significantly reduced NF-κB activation and TNF-α intrapancreatic levels. Furthermore, it decreased inducible nitric oxide synthase and cyclooxygenase 2 expression and activity while it diminished myeloperoxidase activity. ANP also stimulated apoptosis as shown by caspase-3 expression and activation as well as TUNEL assay. These findings correlated well with the ultrastructural changes observed in the exocrine pancreas. Although secretin reduced various inflammatory markers, it also diminished caspase-3 activation and the overall response was the aggravation of the disease as reflected by the ultrastructural alterations of pancreatic acinar cells. In the presence of ANP, various effects evoked by secretin were antagonized.. Present findings show that ANP significantly attenuated the severity of acute pancreatitis in the rat by inducing apoptosis and reducing the inflammatory response and further suggest that ANP may have eventual therapeutic implications in the disease and/or in medical interventions at risk of its developing like endoscopic retrograde cholangiopancreatography.

Topics: Animals; Apoptosis; Atrial Natriuretic Factor; Female; Inflammation; Pancreatitis; Rats; Rats, Sprague-Dawley; Secretin

BACKGROUND The aim of this study was to investigate the effects of sulforaphane (SFN), a natural isothiocyanate compound, in a rabbit ascending aortic cerclage model of chronic heart failure (CHF). MATERIAL AND METHODS Thirty New Zealand White rabbits were divided into the sham operation group (n=10), the CHF group (n=10), and the CHF + SFN group (n=10) treated with subcutaneous SFN (0.5 mg/kg) for five days per week for 12 weeks. After 12 weeks, echocardiography and biometric analysis were performed, followed by the examination of the rabbit hearts. Enzyme-linked immunosorbent assay (ELISA) and Western blot were used to detect levels of inflammatory cytokines, superoxide dismutase (SOD), and malondialdehyde (MDA). RESULTS In the CHF group, compared with the sham operation group, there was an increase in the heart weight to body weight ratio (HW/BW), the left ventricular weight to body weight ratio (LVW/BW), the left ventricular end diastolic diameter (LVEDD), the left ventricular end systolic diameter (LVESD), plasma brain natriuretic peptide (BNP) and atrial natriuretic peptide (ANP) levels, the cardiac collagen volume fraction (CVF), apoptotic index, expression levels of collagen I, collagen III, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and malondialdehyde (MDA) in the myocardial tissue, and a decrease in the left ventricular shortening fraction (LVFS) and left ventricular ejection fraction (LVEF), and cardiac superoxide dismutase (SOD) activity. These changes were corrected in the SFN-treated group. CONCLUSIONS In a rabbit model of CHF, treatment with SFN improved cardiac function and remodeling by inhibiting oxidative stress and inflammation.

Topics: Animals; Apoptosis; Atrial Natriuretic Factor; Chronic Disease; Collagen; Cytokines; Female; Fibrosis; Heart Failure; Heart Function Tests; Hemodynamics; Inflammation; Isothiocyanates; Male; Myocytes, Cardiac; Natriuretic Peptide, Brain; Oxidative Stress; Rabbits; RNA, Messenger; Sulfoxides

The effect of intratracheal lipopolysaccharide (LPS) instillation on right ventricular dysfunction in rats was studied with the aim of exploring underlying mechanisms.. A single dose of LPS (10 mg/kg) or an equal volume of saline was instilled intratracheally and lung injury evaluated using histopathologic scoring and wet/dry (W/D) weight ratio at 6 or 12 h post-administration. Besides, serum atrial natriuretic peptide (ANP) was detected using an enzyme-linked immunosorbent assay (ELISA) and right ventricle β-myosin heavy chain (β-MHC) presence was examined using reverse transcription polymerase chain reaction (RT-PCR). Echocardiography examined pulmonary artery acceleration time (PAAT), right ventricular free wall thickness (RVFWT), tricuspid annular plane systolic excursion (TAPSE), and right ventricular end-diastolic diameter (RVEDD). In addition, right ventricular TUNEL staining and Western blots of Bax and Bcl-2 were performed. Right ventricle and left ventricle caspases-3, -8, and -9 activity were examined using fluorometric assay. Finally, right ventricle myeloperoxidase (MPO) neutrophil staining, and right ventricle and plasma cytokines TNF-α, IL-1β, IL-6 detection was performed.. Histopathologic lung injury and increased W/D weight ratio was seen at 6 h after LPS intratracheal instillation, along with increased ANP, but not β-MHC. Pulmonary hypertension was indicated by decreased PAAT at 6 h post-exposure. Right ventricular systolic dysfunction and dilation were observed at 12 h post-exposure, as indicated by a significant decrease of TAPSE and increase of RVEDD. Of note, the procedure led to an increased right ventricle TUNEL positive cardiomyocytes, an increased Bax/Bcl-2 ratio, and increased right and left ventricle caspases-3, -8, and -9 activity as early as 6 h post-exposure, which was paralleled by increased right ventricle MPO staining and increased expression of right ventricle and serum cytokines TNF-α, IL-1β, and IL-6.. As well as acute lung injury, a single dose of LPS intratracheally instilled can induce pulmonary hypertension at 6 h post-exposure, with obvious right ventricular systolic dysfunction and right ventricular dilation present at 12 h post-exposure, possibly via cardiomyocytes apoptosis and inflammation.

Topics: Acute Lung Injury; Animals; Apoptosis; Atrial Natriuretic Factor; bcl-2-Associated X Protein; Caspases; Cytokines; Disease Models, Animal; Heart Ventricles; Inflammation; Lipopolysaccharides; Male; Myocytes, Cardiac; Neutrophils; Rats, Sprague-Dawley; Up-Regulation; Ventricular Dysfunction, Right

We aimed to investigate the effect of etanercept, a tumor necrosis factor-α (TNF-α) inhibitor, on rat cardiomyocyte hypertrophy and its underlying mechanism. Primary neonatal rat cardiomyocytes were isolated from Sprague-Dawley rats. The model of rat cardiomyocyte hypertrophy was induced by endothelin, and then treated with different concentrations of etanercept (1, 10, and 50 μM). After treatment, cell counts, viability and cell apoptosis were evaluated. The mRNA levels of myocardial hypertrophy marker genes, including atrial natriuretic factor (ANF), matrix metalloproteinase (MMP)-9 and MMP-13, were detected by qRT-PCR, and the expressions of apoptosis-related proteins (Bcl-2 and Bax) were measured by western blotting. The protein levels of transforming growth factor-β1 (TGF-β1), interleukin (IL)-1β, IL-6, leukemia inhibitory factor (LIF) and cardiotrophin-1 (CT-1) were determined using enzyme linked immunosorbent assay (ELISA) kits. In the present study, TNF-α level in cardiomyocytes with hypertrophy was significantly enhanced (P<0.05). Compared to the model group, cell number and viability were significantly increased and ratio of apoptotic cells was reduced by etanercept (P<0.05, P<0.01, or P<0.001). In addition, etanercept remarkably reduced the mRNA levels of ANF, MMP-9 and MMP-13, inhibited the expression of Bax, and increased the expression of Bcl-2 compared to the model group (P<0.05). ELISA results further showed that etanercept lowered the levels of IL-1β, IL-6, LIF and CT-1 but not TGF-β1 compared to the model group (P<0.05). Etanercept may protect rat cardiomyocytes from hypertrophy by inhibiting inflammatory cytokines secretion and cell apoptosis.

Topics: Animals; Animals, Newborn; Anti-Inflammatory Agents, Non-Steroidal; Apoptosis; Atrial Natriuretic Factor; Cardiomegaly; Cell Proliferation; Cell Survival; Cells, Cultured; Cytokines; Disease Models, Animal; Etanercept; Inflammation; Matrix Metalloproteinase 13; Matrix Metalloproteinase 9; Myocytes, Cardiac; Protective Agents; Rats, Sprague-Dawley; Tumor Necrosis Factor-alpha

Atrial natriuretic peptide (ANP) is an hormone/paracrine/autocrine factor regulating cardiovascular homeostasis by guanylyl cyclase natriuretic peptide receptor (NPR-1). ANP plays an important role also in regulating inflammatory and immune systems by altering macrophages functions and cytokines secretion. Interleukin-1β (IL-1β) is a potent pro-inflammatory cytokine involved in a wide range of biological responses, including the immunological one. Unlike other cytokines, IL-1β production is rigorously controlled. Primarily, NF-kB activation is required to produce pro-IL-1β; subsequently, NALP3 inflammasome/caspase-1 activation is required to cleave pro-IL-1β into the active secreted protein. NALP3 is a molecular platform capable of sensing a large variety of signals and a major player in innate immune defense. Due to their pleiotropism, IL-1β and NALP3 dysregulation is a common feature of a wide range of diseases. Therefore, identifying molecules regulating IL-1β/NALP3/caspase-1 expression is an important step in the development of new potential therapeutic agents. The aim of our study was to evaluate the effect of ANP on IL-1β/NALP3/caspase-1 expression in LPS/ATP-stimulated human THP1 monocytes. We provided new evidence of the direct involvement of ANP/NPR-1/cGMP axis on NF-kB/NALP3/caspase-1-mediated IL-1β release and NF-kB-mediated pro-IL-1β production. In particular, ANP inhibited both NF-kB and NALP3/caspase-1 activation leading to pro- and mature IL-1β down-regulation. Our data, pointing out a modulatory role of this endogenous peptide on IL-1β release and on NF-kB/NALP3/caspase-1 activation, indicate an important anti-inflammatory and immunomodulatory effect of ANP via these mechanisms. We suggest a possible employment of ANP for the treatment of inflammatory/immune-related diseases and IL-1β/NALP3-associated disorders, affecting millions of people worldwide.

Topics: Adenosine Triphosphate; Apoptosis; Atrial Natriuretic Factor; Carrier Proteins; Caspase 1; Cell Line; Humans; Immunity, Innate; Immunomodulation; Inflammasomes; Inflammation; Interleukin-1beta; Lipopolysaccharides; Monocytes; NF-kappa B; NLR Family, Pyrin Domain-Containing 3 Protein

In patients after acute myocardial infarction (AMI), the initial extent of necrosis and inflammation determine clinical outcome. One early event in AMI is the increased cardiac expression of atrial natriuretic peptide (NP) and B-type NP, with their plasma levels correlating with severity of ischemia. It was shown that NPs, via their cGMP-forming guanylyl cyclase-A (GC-A) receptor and cGMP-dependent kinase I (cGKI), strengthen systemic endothelial barrier properties in acute inflammation.. We studied whether endothelial actions of local NPs modulate myocardial injury and early inflammation after AMI.. Necrosis and inflammation after experimental AMI were compared between control mice and littermates with endothelial-restricted inactivation of GC-A (knockout mice with endothelial GC-A deletion) or cGKI (knockout mice with endothelial cGKI deletion). Unexpectedly, myocardial infarct size and neutrophil infiltration/activity 2 days after AMI were attenuated in knockout mice with endothelial GC-A deletion and unaltered in knockout mice with endothelial cGKI deletion. Molecular studies revealed that hypoxia and tumor necrosis factor-α, conditions accompanying AMI, reduce the endothelial expression of cGKI and enhance cGMP-stimulated phosphodiesterase 2A (PDE2A) levels. Real-time cAMP measurements in endothelial microdomains using a novel fluorescence resonance energy transfer biosensor revealed that PDE2 mediates NP/cGMP-driven decreases of submembrane cAMP levels. Finally, intravital microscopy studies of the mouse cremaster microcirculation showed that tumor necrosis factor-α-induced endothelial NP/GC-A/cGMP/PDE2 signaling impairs endothelial barrier functions.. Hypoxia and cytokines, such as tumor necrosis factor-α, modify the endothelial postreceptor signaling pathways of NPs, with downregulation of cGKI, induction of PDE2A, and altered cGMP/cAMP cross talk. Increased expression of PDE2 can mediate hyperpermeability effects of paracrine endothelial NP/GC-A/cGMP signaling and facilitate neutrophil extravasation during the early phase after MI.

Topics: Animals; Atrial Natriuretic Factor; Endothelium, Vascular; Human Umbilical Vein Endothelial Cells; Humans; Inflammation; Inflammation Mediators; Mice; Mice, Knockout; Mice, Transgenic; Myocardial Infarction; Tumor Necrosis Factor-alpha

The Goto-Kakizaki (GK) rat, a non-obese model of type 2 diabetes mellitus (T2DM), was generated by the selective inbreeding of glucose-intolerant Wistar rats. This is a convenient model for studying diabetes-induced cardiomyopathy independently from the effects of the metabolic syndrome. We investigated the myocardial functional and structural changes and underlying molecular pathomechanisms of short-term and mild T2DM. The presence of DM was confirmed by an impaired oral glucose tolerance in the GK rats compared with the age-matched nondiabetic Wistar rats. Data from cardiac catheterization showed that in GK rats, although the systolic indexes were not altered, the diastolic stiffness was increased compared with nondiabetics (end-diastolic-pressure-volume-relationship: 0.12 ± 0.04 vs. 0.05 ± 0.01 mmHg/μl, P < 0.05). Additionally, DM was associated with left-ventricular hypertrophy and histological evidence of increased myocardial fibrosis. The plasma pro-B-type natriuretic peptide, the cardiac troponin-T, glucose, and the urinary glucose concentrations were significantly higher in GK rats. Among the 125 genes surveyed using PCR arrays, DM significantly altered the expression of five genes [upregulation of natriuretic peptide precursor-A and connective tissue growth factor, downregulation of c-reactive protein, interleukin-1β, and tumor necrosis factor (TNF)-α mRNA-level]. Of the altered genes, which were evaluated by Western blot, only TNF-α protein expression was significantly decreased. The ECG recordings revealed no significant differences. In conclusion, while systolic dysfunction, myocardial inflammation, and abnormal electrical conduction remain absent, short-term and mild T2DM induce the alteration of cardiac TNF-α at both the mRNA and protein levels. Further assessments are required to reveal if TNF-α plays a role in the early stage of diabetic cardiomyopathy development.

Topics: Animals; Apoptosis; Atrial Natriuretic Factor; Blood Glucose; C-Reactive Protein; Connective Tissue Growth Factor; Diabetes Mellitus, Type 2; Down-Regulation; Echocardiography; Electrocardiography; Fibrosis; Glucose Tolerance Test; Glycosuria; Hypertrophy, Left Ventricular; Immunohistochemistry; In Situ Nick-End Labeling; Inflammation; Interleukin-1beta; Male; Myocardium; Natriuretic Peptide, Brain; Oxidative Stress; Peptide Fragments; Polymerase Chain Reaction; Rats; Rats, Wistar; RNA, Messenger; Signal Transduction; Troponin T; Tumor Necrosis Factor-alpha; Tyrosine; Up-Regulation; Ventricular Dysfunction, Left; Ventricular Function, Left; Ventricular Pressure

Most patients suffering from cancer die of metastatic disease. Surgical removal of solid tumors is performed as an initial attempt to cure patients; however, surgery is often accompanied with trauma, which can promote early recurrence by provoking detachment of tumor cells into the blood stream or inducing systemic inflammation or both. We have previously reported that administration of atrial natriuretic peptide (ANP) during the perioperative period reduces inflammatory response and has a prophylactic effect on postoperative cardiopulmonary complications in lung cancer surgery. Here we demonstrate that cancer recurrence after curative surgery was significantly lower in ANP-treated patients than in control patients (surgery alone). ANP is known to bind specifically to NPR1 [also called guanylyl cyclase-A (GC-A) receptor]. In mouse models, we found that metastasis of GC-A-nonexpressing tumor cells (i.e., B16 mouse melanoma cells) to the lung was increased in vascular endothelium-specific GC-A knockout mice and decreased in vascular endothelium-specific GC-A transgenic mice compared with control mice. We examined the effect of ANP on tumor metastasis in mice treated with lipopolysaccharide, which mimics systemic inflammation induced by surgical stress. ANP inhibited the adhesion of cancer cells to pulmonary arterial and micro-vascular endothelial cells by suppressing the E-selectin expression that is promoted by inflammation. These results suggest that ANP prevents cancer metastasis by inhibiting the adhesion of tumor cells to inflamed endothelial cells.

Topics: Animals; Atrial Natriuretic Factor; Cell Adhesion; Cell Line, Tumor; Disease-Free Survival; Endothelial Cells; Green Fluorescent Proteins; Humans; Inflammation; Kaplan-Meier Estimate; Lung Neoplasms; Melanoma, Experimental; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Knockout; Neoplasm Metastasis; Neoplasm Recurrence, Local; Neoplasms; Retrospective Studies

Subjects carrying the T2238C ANP gene variant have a higher risk to suffer a stroke or myocardial infarction. The mechanisms through which T2238C/αANP exerts detrimental vascular effects need to be fully clarified. In the present work we aimed at exploring the impact of C2238/αANP (mutant form) on atherosclerosis-related pathways. As a first step, an atherosclerosis gene expression macroarray analysis was performed in vascular smooth muscle cells (VSMCs) exposed to either T2238/αANP (wild type) or C2238/αANP. The major finding was that apolipoprotein E (ApoE) gene expression was significantly downregulated by C2238/αANP and it was upregulated by T2238/αANP. We subsequently found that C2238/αANP induces ApoE downregulation through type C natriuretic peptide receptor (NPR-C)-dependent mechanisms involving the upregulation of miR199a-3p and miR199a-5p and the downregulation of DNAJA4. In fact, NPR-C knockdown rescued ApoE level. Upregulation of miR199a by NPR-C was mediated by a reactive oxygen species-dependent increase of the early growth response protein-1 (Egr-1) transcription factor. In fact, Egr-1 knockdown abolished the impact of C2238/αANP on ApoE and miR199a. Of note, downregulation of ApoE by C2238/αANP was associated with a significant increase in inflammation, apoptosis and necrosis that was completely rescued by the exogenous administration of recombinant ApoE. In conclusion, our study dissected a novel mechanism of vascular damage exerted by C2238/αANP that is mediated by ApoE downregulation. We provide the first demonstration that C2238/αANP downregulates ApoE in VSMCs through NPR-C-dependent activation of Egr-1 and the consequent upregulation of miR199a. Restoring ApoE levels could represent a potential therapeutic strategy to counteract the harmful effects of C2238/αANP.

Topics: Apolipoproteins E; Apoptosis; Atherosclerosis; Atrial Natriuretic Factor; Biomarkers; Cell Survival; Coronary Vessels; Early Growth Response Protein 1; Humans; Inflammation; MicroRNAs; Models, Biological; Muscle, Smooth, Vascular; Mutation; Myocytes, Smooth Muscle; Necrosis; Reactive Oxygen Species; Real-Time Polymerase Chain Reaction; Receptors, Atrial Natriuretic Factor; RNA, Messenger; Umbilical Veins; Up-Regulation

The growing incidence of chronic kidney disease remains a global health problem. Obesity is a major risk factor for type-2 diabetes and renal impairment. Perirenal adiposity, by virtue of its anatomical proximity to the kidneys may cause kidney disease through paracrine mechanisms that include increased production of inflammatory cytokines. Although heme-oxygenase (HO) is cytoprotective, its effects on perirenal adiposity and diabetic nephropathy in Zucker-diabetic fatty rats (ZDFs) remains largely unclear. Upregulating the HO-system with hemin normalised glycemia, reduced perirenal adiposity and suppressed several pro-inflammatory/oxidative mediators in perirenal fat including macrophage-inflammatory-protein-1α (MIP-1α), endothelin (ET-1), 8-isoprostane, TNF-α, IL-6 and IL-1β. Furthermore, hemin reduced ED1, a marker of pro-inflammatory macrophage-M1-phenotype, but interestingly, enhanced markers associated with anti-inflammatory M2-phenotype such as ED2, CD206 and IL-10, suggesting that hemin selectively modulates macrophage polarization towards the anti-inflammatory M2-phenotype. These effects were accompanied by increased adiponectin, HO-1, HO-activity, atrial-natriuretic peptide (ANP), and its surrogate marker, urinary-cGMP. Furthermore, hemin reduced renal histological lesions and abated pro-fibrotic/extracellular-matrix proteins like collagen and fibronectin that deplete nephrin, an important transmembrane protein which forms the scaffolding of the podocyte slit-diaphragm allowing ions to filter but not massive excretion of proteins, hence proteinuria. Correspondingly, hemin increased nephrin expression in ZDFs, reduced markers of renal damage including, albuminuria/proteinuria, but increased creatinine-clearance, suggesting improved renal function. Conversely, the HO-blocker, stannous-mesoporphyrin nullified the hemin effects, aggravating glucose metabolism, and exacerbating renal injury and function. The hemin effects were less-pronounced in Zucker-lean controls with healthy status, suggesting greater selectivity of HO in ZDFs with disease. We conclude that the concomitant reduction of pro-inflammatory/oxidative mediators, macrophage infiltration and profibrotic/extracellular-matrix proteins, coupled to increased nephrin, adiponectin, ANP, cGMP and creatinine clearance may account for improved renal function in hemin-treated ZDFs. These findings suggest that HO-inducers like hemin may be explored against the co-morbidity of perirenal adiposity an

Topics: Adiposity; Animals; Atrial Natriuretic Factor; Blood Glucose; Chemokine CCL3; Diabetic Nephropathies; Dinoprost; Endothelin-1; Extracellular Matrix Proteins; Heme Oxygenase (Decyclizing); Hemin; Inflammation; Interleukins; Kidney; Macrophages; Male; Rats; Rats, Zucker; Tumor Necrosis Factor-alpha

Topics: Animals; Atrial Natriuretic Factor; Humans; Inflammation; Myocytes, Cardiac; Natriuretic Peptide, Brain

Topics: Animals; Atrial Natriuretic Factor; Humans; Inflammation; Myocytes, Cardiac; Natriuretic Peptide, Brain

Endurance athletes have an increased risk of atrial fibrillation. We performed a longitudinal study on elite runners of the 2010 Jungfrau Marathon, a Swiss mountain marathon, to determine acute effects of long-distance running on the atrial myocardium. Ten healthy male athletes were included and examined 9 to 1 week prior to the race, immediately after, and 1, 5, and 8 days after the race. Mean age was 34.9 ± 4.2 years, and maximum oxygen consumption was 66.8 ± 5.8 mL/kg*min. Mean race time was 243.9 ± 17.7 min. Electrocardiographic-determined signal-averaged P-wave duration (SAPWD) increased significantly after the race and returned to baseline levels during follow-up (128.7 ± 10.9 vs. 137.6 ± 9.8 vs. 131.5 ± 8.6 ms; P < 0.001). Left and right atrial volumes showed no significant differences over time, and there were no correlations of atrial volumes and SAPWD. Prolongation of the SAPWD was accompanied by a transient increase in levels of high-sensitivity C-reactive protein, proinflammatory cytokines, total leucocytes, neutrophil granulocytes, pro atrial natriuretic peptide and high-sensitivity troponin. In conclusion, marathon running was associated with a transient conduction delay in the atria, acute inflammation and increased atrial wall tension. This may reflect exercise-induced atrial myocardial edema and may contribute to atrial remodeling over time, generating a substrate for atrial arrhythmias.

Topics: Adult; Atrial Natriuretic Factor; Atrial Remodeling; C-Reactive Protein; Electrocardiography; Heart Atria; Humans; Inflammation; Interleukin-6; Leukocyte Count; Longitudinal Studies; Male; Neutrophils; Prospective Studies; Running; Troponin; Tumor Necrosis Factor-alpha; Ultrasonography

Trypanosoma cruzi, the causative agent of Chagas' disease, induces multiple responses in the heart, a critical organ of infection and pathology in the host. Among diverse factors, eicosanoids and the vasoactive peptide endothelin-1 (ET-1) have been implicated in the pathogenesis of chronic chagasic cardiomyopathy. In the present study, we found that T. cruzi infection in mice induces myocardial gene expression of cyclooxygenase-2 (Cox2) and thromboxane synthase (Tbxas1) as well as endothelin-1 (Edn1) and atrial natriuretic peptide (Nppa). T. cruzi infection and ET-1 cooperatively activated the Ca(2+)/calcineurin (Cn)/nuclear factor of activated T cells (NFAT) signaling pathway in atrial myocytes, leading to COX-2 protein expression and increased eicosanoid (prostaglandins E(2) and F(2α), thromboxane A(2)) release. Moreover, T. cruzi infection of ET-1-stimulated cardiomyocytes resulted in significantly enhanced production of atrial natriuretic peptide (ANP), a prognostic marker for impairment in cardiac function of chagasic patients. Our findings support an important role for the Ca(2+)/Cn/NFAT cascade in T. cruzi-mediated myocardial production of inflammatory mediators and may help define novel therapeutic targets.

Topics: Animals; Atrial Natriuretic Factor; Calcineurin; Calcium; Cyclooxygenase 2; Endothelin-1; Gene Expression Profiling; Inflammation; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Monocytes; Myocytes, Cardiac; Natriuretic Peptide, C-Type; NFATC Transcription Factors; Protein Precursors; Signal Transduction; Thromboxane-A Synthase; Trypanosoma cruzi

An inflammatory response leading to organ dysfunction and failure continues to be a major problem after injury in many clinical conditions such as sepsis, severe burns, and trauma. It is increasingly recognized that atrial natriuretic peptide (ANP) possesses a broad range of biological activities, including effects on endothelial function and inflammation. A recent study has revealed that ANP exerts anti-inflammatory effects. In this study we tested the effects of human ANP (hANP) on lung injury in a model of oleic acid (OA)-induced acute lung injury (ALI) in rats.. Rats were randomly assigned to three groups (n = 6 in each group). Rats in the control group received a 0.9% solution of NaCl (1 ml × kg(-1) × h(-1)) by continuous intravenous infusion, after 30 minutes a 0.9% solution of NaCl (1 ml/kg) was injected intravenously, and then the 0.9% NaCl infusion was restarted. Rats in the ALI group received a 0.9% NaCl solution (1 ml × kg(-1) × h(-1)) intravenous infusion, after 30 minutes OA was injected intravenously (0.1 ml/kg), and then the 0.9% NaCl infusion was restarted. Rats in the hANP-treated ALI group received a hANP (0.1 µg × kg(-1) × min(-1)) infusion, after 30 minutes OA was injected intravenously (0.1 ml/kg), and then the hANP infusion was restarted. The anti-inflammation effects of hANP were evaluated by histological examination and determination of serum cytokine levels.. Serum interleukin (IL)-1β, IL-6, IL-10 and tumor necrosis factor (TNF) α were increased in the ALI group at six hours. The levels of all factors were significantly lower in the hANP treated rats (P < 0.005). Similarly, levels of IL-1β, IL-6, IL-10 and TNF-α were higher in the lung tissue in the ALI group at six hours. hANP treatment significantly reduced the levels of these factors in the lungs (P < 0.005). Histological examination revealed marked reduction in interstitial congestion, edema, and inflammation.. hANP can attenuate inflammation in an OA-induced lung injury in rat model.

Topics: Acute Lung Injury; Animals; Atrial Natriuretic Factor; Disease Models, Animal; Inflammation; Male; Oleic Acid; Rats; Rats, Wistar

Ischemia-reperfusion injury (IRI) is a major cause of cardiac damage following various pathological processes. Gaseous hydrogen sulfide (H2S) is protective during IRI by inducing a hypometabolic state in mice which is associated with anti-apoptotic, anti-inflammatory and antioxidant properties. We investigated whether gaseous H2S administration is protective in cardiac IRI and whether non-hypometabolic concentrations of H2S have similar protective properties.. Male C57BL/6 mice received a 0, 10, or 100 ppm H2S-N2 mixture starting 30 minutes prior to ischemia until 5 minutes pre-reperfusion. IRI was inflicted by temporary ligation of the left coronary artery for 30 minutes. High-resolution respirometry equipment was used to assess CO2-production and blood pressure was measured using internal transmitters. The effects of H2S were assessed by histological and molecular analysis.. Treatment with 100 ppm H2S decreased CO2-production by 72%, blood pressure by 14% and heart rate by 25%, while treatment with 10 ppm H2S had no effects. At day 1 of reperfusion 10 ppm H2S showed no effect on necrosis, while treatment with 100 ppm H2S reduced necrosis by 62% (p<0.05). Seven days post-reperfusion, both 10 ppm (p<0.01) and 100 ppm (p<0.05) H2S showed a reduction in fibrosis compared to IRI animals. Both 10 ppm and 100 ppm H2S reduced granulocyte-influx by 43% (p<0.05) and 60% (p<0.001), respectively. At 7 days post-reperfusion both 10 and 100 ppm H2S reduced expression of fibronectin by 63% (p<0.05) and 67% (p<0.01) and ANP by 84% and 63% (p<0.05), respectively.. Gaseous administration of H2S is protective when administered during a cardiac ischemic insult. Although hypometabolism is restricted to small animals, we now showed that low non-hypometabolic concentrations of H2S also have protective properties in IRI. Since IRI is a frequent cause of myocardial damage during percutaneous coronary intervention and cardiac transplantation, H2S treatment might lead to novel therapeutical modalities.

Topics: Animals; Atrial Natriuretic Factor; Blood Pressure; Carbon Dioxide; Cell Line; Disease Models, Animal; Gene Expression; Heart Rate; Hydrogen Sulfide; Inflammation; Male; Membrane Glycoproteins; Mice; Myoblasts, Cardiac; Myocardial Reperfusion Injury; Myocardium; NADPH Oxidase 2; NADPH Oxidase 4; NADPH Oxidases; Oxidative Stress; Rats

We have previously demonstrated that catheter-based renal sympathetic denervation (RSD) could suppress atrial fibrillation (AF) in canines with short-time rapid right atrial pacing (RAP). However, the role of renal denervation on atrial remodeling is unclear. The aim of the present study was to explore the long-term effect of RSD on the atrial remodeling during prolonged RAP. Twenty mongrel dogs were implanted with a high-frequency cardiac pacemaker with a transvenous lead inserted into the right atrial appendage. The dogs were divided into three groups: a sham-operated group (n = 6), the chronic RAP (CRAP) group (n = 7), and the CRAP+RSD group (n = 7). In the CRAP+RSD group, a pacemaker was implanted 6 weeks after RSD was performed bilaterally for recovery. RAP was maintained for 5 weeks in CRAP group and CRAP+RSD group. The plasma levels of Angiotensin II and aldosterone were significantly increased in CRAP group compared with sham-operated group, but the increasing trend was inhibited in CRAP+RSD group compared with CRAP group (P<0.05). Similarly, RSD suppressed the increasing trend that prolonged RAP produced in the left atrial levels of ANP, TNF-α and IL-6. Compared with the sham-operated group, the CRAP group had significantly increased levels of caspase-3, bax and Cx40 whereas the level of Bcl-2 decreased (P<0.05). RSD markedly reduced the upregulation of caspase-3, bax and Cx40 and the downregulation of Bcl-2 expression compared with the CRAP group (P<0.05). Picric acid-sirius red staining study suggested that RSD could markedly alleviate the lesion degree of cardic fibrosis induced by CRAP (P<0.05). Immunohistochemistry results showed that the densities of TH- and GAP43- positive nerves were significantly elevated in the CRAP group compared with the sham-operated group, while RSD operation signicantly inhibited the these changes produced by CRAP. These findings suggest that renal denervation could suppress the atrial remodeling after prolonged RAP in ambulatory canines.

Topics: Aldosterone; Angiotensin II; Animals; Apoptosis; Atrial Fibrillation; Atrial Natriuretic Factor; Atrial Remodeling; Blood Pressure; Cardiac Pacing, Artificial; Dogs; Fibrosis; Gap Junctions; GAP-43 Protein; Heart Atria; Inflammation; Interleukin-6; Kidney; Myocytes, Cardiac; Sympathectomy; Tumor Necrosis Factor-alpha

Postoperative-fluid retention is a severe complication frequently reported in patients undergoing major surgical procedures. The complex network of molecules involved in such a severe surgery-induced condition remains poorly understood. Inflammation has been proposed among the various causes of fluid retention. Since TNF-α is one of the main proinflammatory cytokine initially released after major surgery, it is reasonable to assume its involvement in fluid overload. Here, we showed that TNF-α selectively regulates key molecules involved in fluids balance, such as natriuretic peptides (NPs) and aquaporins, in human bronchial epithelial cells BEAS-2B. In particular, we found that TNF-α induced a decrease of arial natriuretic peptide, natriuretic peptide receptor-1, aquaporin-1 and aquaporin-5 and an increase of brain natriuretic peptide with a different involvement of nuclear factor-κB and mitogen-activated protein kinases signaling pathway activation. Moreover, the observed changes in NPs expression, demonstrate inflammation as an additional cause of brain natriuretic peptide elevation, adding an important piece of information in the novel area of study regarding NPs and inflammation. Finally, we suggest that inflammation is one of the mechanisms of Aquaporin-1 and aquaporin-5 expression regulation. Therefore, in this exploratory study, we speculate that TNF-α might be involved in postoperative-fluid retention related to major surgery.

Topics: Aquaporin 1; Aquaporin 5; Atrial Natriuretic Factor; Bronchi; Cell Line; Cell Survival; Culture Media; Dexamethasone; Epithelial Cells; Gene Expression Profiling; Gene Expression Regulation; Hemodynamics; Homeostasis; Humans; Inflammation; Natriuretic Peptide, Brain; NF-kappa B; Polymerase Chain Reaction; Receptors, Atrial Natriuretic Factor; Signal Transduction; Tumor Necrosis Factor-alpha

Although many obese individuals are normoglycemic and asymptomatic of cardiometabolic complications, this apparent healthy state may be a misnomer. Since heart failure is a major cause of mortality in obesity, we investigated the effects of heme-oxygenase (HO) on heart failure and cardiometabolic complications in obese normoglycemic Zucker-fatty rats (ZFs). Treatment with the HO-inducer, hemin, reduced markers of heart failure, such as osteopontin and osteoprotegerin, abated left-ventricular (LV) hypertrophy/fibrosis, extracellular matrix/profibrotic proteins including collagen IV, fibronectin, TGF-β1, and reduced cardiac lesions. Furthermore, hemin suppressed inflammation by abating macrophage chemoattractant protein-1, macrophage-inflammatory protein-1 alpha, TNF-α, IL-6, and IL-1β but enhanced adiponectin, atrial-natriuretic peptide (ANP), HO activity, insulin sensitivity, and glucose metabolism. Correspondingly, hemin improved several hemodynamic/echocardiographic parameters including LV-diastolic wall thickness, LV-systolic wall thickness, mean-arterial pressure, arterial-systolic pressure, arterial-diastolic pressure, LV-developed pressure, +dP/dt, and cardiac output. Contrarily, the HO-inhibitor, stannous mesoporphyrin nullified the hemin effect, exacerbating inflammatory/oxidative insults and aggravated insulin resistance (HOMA-index). We conclude that perturbations in insulin signaling and cardiac function may be forerunners to overt hyperglycemia and heart failure in obesity. Importantly, hemin improves cardiac function by suppressing markers of heart failure, LV hypertrophy, cardiac lesions, extracellular matrix/profibrotic proteins, and inflammatory/oxidative mediators, while concomitantly enhancing the HO-adiponectin-ANP axis.

Topics: Adiponectin; Animals; Atrial Natriuretic Factor; Blood Glucose; Chemokine CCL2; Dinoprost; Endothelin-1; Heart Failure; Heart Function Tests; Heart Ventricles; Heme Oxygenase (Decyclizing); Hemin; Hemodynamics; Inflammation; Insulin; Insulin Resistance; Macrophage Inflammatory Proteins; Macrophages; Metalloporphyrins; Myocytes, Cardiac; Obesity; Rats; Rats, Zucker; Risk Factors; Tumor Necrosis Factor-alpha; Ultrasonography; Up-Regulation

We aimed to investigate whether atrial natriuretic peptide (ANP) attenuates angiotensin II (Ang II)-induced myocardial remodeling and to clarify the possible molecular mechanisms involved. Thirty-five 8-week-old male Wistar-Kyoto rats were divided into control, Ang II, Ang II + ANP, and ANP groups. The Ang II and Ang II + ANP rats received 1 μg/kg/min Ang II for 14 days. The Ang II + ANP and ANP rats also received 0.1 μg/kg/min ANP intravenously. The Ang II and Ang II + ANP rats showed comparable blood pressure. Left ventricular fractional shortening and ejection fraction were lower in the Ang II rats than in controls; these indices were higher (P < 0.001) in the Ang II + ANP rats than in the Ang II rats. In the Ang II rats, the peak velocity of mitral early inflow and its ratio to atrial contraction-related peak flow velocity were lower, and the deceleration time of mitral early inflow was significantly prolonged; these changes were decreased by ANP. Percent fibrosis was higher (P < 0.001) and average myocyte diameters greater (P < 0.01) in the Ang II rats than in controls. ANP decreased both myocardial fibrosis (P < 0.01) and myocyte hypertrophy (P < 0.01). Macrophage infiltration, expression of mRNA levels of collagen types I and III, monocyte chemotactic protein-1, and a profibrotic/proinflammatory molecule, tenascin-C (TN-C) were increased in the Ang II rats; ANP significantly decreased these changes. In vitro, Ang II increased expression of TN-C and endothelin-1 (ET-1) in cardiac fibroblasts, which were reduced by ANP. ET-1 upregulated TN-C expression via endothelin type A receptor. These results suggest that ANP may protect the heart from Ang II-induced remodeling by attenuating inflammation, at least partly through endothelin 1/endothelin receptor A cascade.

Topics: Angiotensin II; Animals; Anti-Inflammatory Agents; Atrial Natriuretic Factor; Cardiomegaly; Cells, Cultured; Disease Models, Animal; Endothelin-1; Fibrillar Collagens; Fibroblasts; Fibrosis; Heart Diseases; Inflammation; Inflammation Mediators; Infusions, Intravenous; Macrophages; Male; Mitral Valve; Myocardial Contraction; Myocardium; Rats; Rats, Inbred WKY; Receptor, Endothelin A; Signal Transduction; Stroke Volume; Time Factors; Ventricular Function, Left; Ventricular Remodeling

We investigated the expression and secretion of the natriuretic peptides (NPs) ANF and BNP in lipopolysaccharide (LPS)-induced sepsis and its association with cytokines and other biologically active substances. LPS treatment increased plasma levels of ANF and BNP. The latter increase was larger than the increase in plasma ANF. LPS also increased cardiac content and gene expression of BNP but not of ANF. LPS treatment significantly increased gene expression cytokines, chemokines and proteases, which significantly correlated with BNP gene expression. SB203580, a p38 MAP kinase inhibitor, inhibited the elevation of BNP in plasma. The present work suggests that during inflammation, BNP gene expression and secretion is uniquely related to changes in gene expression in the absence of hemodynamic changes and hence differentiates ANF and BNP as biomarkers of cardiac disease.

Topics: Animals; Atrial Natriuretic Factor; Biomarkers; Cytokines; Dose-Response Relationship, Drug; Enzyme Inhibitors; Gene Expression Regulation; Imidazoles; Inflammation; Lipopolysaccharides; Myocardium; Natriuretic Peptide, Brain; p38 Mitogen-Activated Protein Kinases; Pyridines; Rats; Rats, Sprague-Dawley; Sepsis; Signal Transduction

Doxorubicin [(DOX) Adriamycin] is an effective anticancer agent whose major limiting side effect is cardiotoxicity. This cardiotoxicity is predicted only by the cumulative dose of DOX where the clinical situation involves chronic drug administration. Therefore, we investigate the effect of chronic DOX cardiotoxicity on expression of the cardiac cytochrome P450 (P450) enzymes and arachidonic acid (AA) metabolism in male Sprague-Dawley (SD) rats. The chronic toxicity was induced by multiple intraperitoneal injections for a cumulative dose of 15 mg/kg divided into six injections within 2 weeks. After 14 days of the last injection, the heart, liver, and kidney were harvested, and the expression of different genes was determined by real-time polymerase chain reaction. In addition, microsomal protein from the heart was prepared and incubated with AA. Thereafter, different AA metabolites were analyzed by liquid chromatography-electrospray ionization-mass spectrometry. The chronic DOX cardiotoxicity significantly induced gene expression of hypertrophic markers, apoptotic markers, CYP2E1, CYP4A3, CYP4F1, CYP4F5, and soluble epoxide hydrolase (sEH) enzyme, which was accompanied by an increase in the activity of P450 ω-hydroxylases and sEH. In addition, both the sEH inhibitor, trans-4-[4-(3-adamantan-1-yl-ureido)-cyclohexyloxy]-benzoic acid, and the ω-hydroxylase inhibitor, N-hydroxy-N'-(4-butyl-2-methylphenyl)-formamidine (HET0016), significantly prevented the DOX-mediated induction of the hypertrophic markers in the cardiac-derived H9c2 cells, which further confirms the role of these enzymes in DOX cardiotoxicity. Furthermore, gene expression of P450 and sEH was altered in an organ-specific manner. As a result, the chronic DOX administration leads to an imbalance between P450-mediated cardiotoxic and cardioprotective pathways. Therefore, P450 ω-hydroxylases and sEH might be considered as novel targets to prevent and/or treat DOX cardiotoxicity.

Topics: Animals; Apoptosis; Arachidonic Acid; Atrial Natriuretic Factor; Biomarkers; Cardiomyopathy, Hypertrophic; Cells, Cultured; Cytochrome P-450 CYP4A; Cytochrome P-450 Enzyme System; Doxorubicin; Epoxide Hydrolases; Gene Expression; Heart; Inflammation; Kidney; Liver; Male; Microsomes; Myocardium; Natriuretic Peptide, Brain; Rats; Rats, Sprague-Dawley; RNA, Messenger

Inflammation involves the cooperation of various cells and biologically active molecules. An important intracellular messenger molecule participating in the regulation of the process is cyclic GMP (cGMP), which is synthesized by guanylyl cyclases (GCs). The GC family comprises cytosolic (soluble) and membrane-bound (particulate) enzymes. The aim of this study was to determine whether and how the synthesis of cGMP by various forms of GC affects the expression of inflammatory cytokines depending on the activity of the transcription factors NF-κB (nuclear factor-κB) and AP-1 (activator protein-1). We established that in rat peripheral blood mononuclear cells (PBMCs), synthesis of cGMP was elevated by sodium nitroprusside (SNP), the activator of soluble GC, and by atrial natriuretic peptide (ANP) and C-type natriuretic peptide (CNP), the activators of particulate GC-A and GC-B, respectively. Stimulation of various GCs differently affected the expressions of the cytokines IL-1β, IL-6, and TNF-α in control cells and in cells activated by bacterial endotoxin (LPS). In control PBMCs their expression was elevated by stimulation of soluble, but not particulate, GC. SNP caused an increase in NF-κB activity, but had no influence on the activity of AP-1. The cells treated with LPS decreased the expressions of IL-1β, IL-6, and TNF-α in response to stimulation of particulate GC-A, but not other guanylyl cyclases. This inhibitory effect was a result of suppression of the activities of NF-κB and AP-1. Both effects that of SNP and of ANP, were cGMP dependent, as shown using its membrane-permeable analog 8-Br-cGMP. The implementation of specific inhibitors showed that the stimulatory effect of SNP was mediated by soluble GC and cGMP-dependent protein kinase (PKG-I). However, PKG-I was not involved in the inhibition of NF-κB and AP-1 activities by ANP in LPS-activated cells. Taken together, these results for the first time indicate that various GCs and various cGMP-dependent signaling pathways can modulate the activity of AP-1 and/or NF-κB and thus affect the expressions of IL-1β, IL-6, and TNF-α, which play important roles in the development of inflammation.

Topics: Animals; Atrial Natriuretic Factor; Blotting, Western; Cyclic GMP; Cyclic GMP-Dependent Protein Kinase Type I; Cyclic GMP-Dependent Protein Kinases; Cytokines; Electrophoretic Mobility Shift Assay; Gene Expression Regulation; Guanylate Cyclase; Inflammation; Leukocytes, Mononuclear; Lipopolysaccharides; Natriuretic Peptide, C-Type; Nitroprusside; Rats; Reverse Transcriptase Polymerase Chain Reaction; Signal Transduction; Solubility; Transcription Factor AP-1

Atrial natriuretic peptide (ANP) is widely distributed throughout the heart, skin, gastrointestinal and genital tracts, and nervous and immune systems. ANP acts to mediate vasodilation and induces mast cell activation in both human and rats in vitro. However, the mechanisms of ANP-induced mast cell activation, the extent to which ANP can induce tissue swelling, mast cell degranulation, and granulocyte infiltration in mouse skin are not fully understood. This issue was investigated by treatment with ANP in rat peritoneal mast cells (RPMCs) and mouse peritoneal mast cells (MPMCs) in vitro and by injection of ANP into the skin of congenic normal WBB6F1/J-Kit+/Kit+ +/+, genetically mast cell-deficient WBB6F1/J-Kit(W)/Kit(W-v) (W/W(v)) and mast cell-engrafted W/W(v) (BMCMC→W/W(v)) mice in vivo. ANP induced the release of histamine and TNF-α from RPMCs and enhanced serotonin release from MPMCs, in a dose-dependent fashion, as well as reduced cAMP level of RPMCs in vitro. In +/+ mice, ANP induced significant tissue swelling, mast cell degranulation, and granulocyte infiltration in a dose-dependent manner, whereas not in genetically mast cell-deficient W/W(v) mice. However, ANP-induced cutaneous inflammation has been restored in BMCMC→W/W(v) mice. These data indicate that mast cells play a key role in the ANP-induced cutaneous inflammation.

Topics: Administration, Cutaneous; Animals; Atrial Natriuretic Factor; Cell Degranulation; Dose-Response Relationship, Immunologic; Granulocytes; Histamine; Humans; Inflammation; Male; Mast Cells; Mice; Mice, Inbred C57BL; Mice, Transgenic; Neutrophil Infiltration; Peritoneum; Rats; Serotonin; Skin; Transplants; Tumor Necrosis Factor-alpha; Vasodilation

We have previously reported protective effects of atrial natriuretic peptide (ANP) against endothelial cell (EC) permeability induced by thrombin via suppression of Rho GTPase pathway of barrier dysfunction by protein kinase A and Epac-Rap1-Tiam1-Rac signaling cascades. This study tested effects of ANP on EC barrier dysfunction induced by inflammatory mediators lipopolysaccharide (LPS) and TNFalpha and linked them with activation of mitogen-activated protein kinase (MAPK) and NFkappaB signaling cascades known to promote EC hyperpermeability in the models of lung inflammation and sepsis. LPS and TNFalpha increased permeability in human pulmonary EC monitored by measurements of transendothelial electrical resistance, and caused disruption of EC monolayer integrity monitored by immunofluorescence staining for adherens junction marker protein VE-cadherin. Both disruptive effects were markedly attenuated by ANP. Both LPS and TNFalpha caused sustained activation of p38 and ERK1/2 MAP kinases, increased phosphorylation and degradation of negative regulator of NFkappaB signaling IkBalpha, and increased Rho-kinase mediated phosphorylation of myosin phosphatase MYPT1 leading to accumulation of phosphorylated myosin light chains. Consistent with protective effects on EC permeability and monolayer integrity, ANP dramatically attenuated activation of inflammatory signaling by LPS and TNFalpha in pulmonary EC. These results strongly suggest inhibitory effects of ANP on the LPS and TNFalpha induced inflammatory signaling as additional mechanism of EC barrier preservation in the models of acute lung injury and sepsis.

Topics: Adherens Junctions; Antigens, CD; Atrial Natriuretic Factor; Cadherins; Capillary Permeability; Cells, Cultured; Electric Impedance; Endothelial Cells; Enzyme Activation; Fluorescent Antibody Technique; Humans; I-kappa B Proteins; Inflammation; Inflammation Mediators; Lipopolysaccharides; Lung; Mitogen-Activated Protein Kinases; Myosin-Light-Chain Phosphatase; NF-kappa B; NF-KappaB Inhibitor alpha; Phosphorylation; rho-Associated Kinases; Signal Transduction; Time Factors; Tumor Necrosis Factor-alpha

Adiponectin is an adipose tissue-derived adipokine abundant in human plasma. Increasing evidence from experimental studies suggests that adiponectin plays a protective role in the cardiovascular system. However, epidemiological studies revealed that high levels of adiponectin were associated with increased mortality and severity of congestive heart failure. Furthermore, several prospective studies indicated that high levels of adiponectin were positively correlated with increased total and cardiovascular disease mortality in the elderly. These results are completely opposite to our expectation based on the beneficial effects of adiponectin. Clinical observations demonstrated that plasma adiponectin levels were positively associated with B-type natriuretic peptide levels. Clinical and experimental studies indicated that the administration of atrial natriuretic peptide enhanced adiponectin production. It is still controversial whether increased adiponectin production is a bystander or a key mediator in the development of heart failure. However, recent investigations strongly suggest that increased adiponectin production in patients with heart failure is a part of compensatory mechanisms against oxidative stress and inflammation. In addition, complicated "adiponectin resistance" will accelerate a counter-regulatory increase in adiponectin in patients with advanced heart failure, although direct evidence that patients with heart failure have "adiponectin resistance" is still lacking. Increased adiponectin production might contribute, at least in part, to the metabolic and structural remodeling of the failing heart via activation of AMP-activated protein kinase and induction of cyclooxygenase-2. Further investigation is needed to clarify the exact role of increased adiponectin production under pathophysiological conditions.

Topics: Adiponectin; Aging; AMP-Activated Protein Kinases; Atrial Natriuretic Factor; Cardiovascular Diseases; Cyclooxygenase 2; Heart Failure; Humans; Inflammation; Japan; Oxidative Stress; Risk Factors; Signal Transduction

The cardiorenal syndromes (CRS) are composed of five recently defined syndromes which represent common clinical scenarios in which both the heart and the kidney are involved in a bidirectional injury process leading to dysfunction of both organs. Common to each subtype are multiple complex pathogenic factors, a precipitous decline in function and a progressive course. Most pathways that lead to CRS involve acute injury to organs which manifest evidence of chronic disease, suggesting reduced ability to sustain damage, maintain vital functions, and facilitate recovery. Prevention of CRS is an ideal clinical goal, because once initiated, CRS cannot be readily aborted, are not completely reversible, and are associated with serious consequences including hospitalization, complicated procedures, need for renal replacement therapy, and death. Principles of prevention include identification and amelioration of precipitating factors, optimal management of both chronic heart and kidney diseases, and future use of multimodality therapies for end-organ protection at the time of systemic injury. This paper will review the core concepts of prevention of CRS with practical applications to be considered in today's practice.

Topics: Anemia; Atrial Natriuretic Factor; Cardiotonic Agents; Dopamine; Heart Failure; Humans; Inflammation; Infusions, Intravenous; Kidney Diseases; Kidney Failure, Chronic; Myocardial Ischemia; Randomized Controlled Trials as Topic; Renal Circulation; Sleep Apnea, Obstructive; Sodium; Sodium Potassium Chloride Symporter Inhibitors; Syndrome

Mechanisms promoting the transition from hypertensive heart disease to heart failure with preserved ejection fraction are poorly understood. When inappropriate for salt status, mineralocorticoid (deoxycorticosterone acetate) excess causes hypertrophy, fibrosis, and diastolic dysfunction. Because cardiac mineralocorticoid receptors are protected from mineralocorticoid binding by the absence of 11-beta hydroxysteroid dehydrogenase, salt-mineralocorticoid-induced inflammation is postulated to cause oxidative stress and to mediate cardiac effects. Although previous studies have focused on salt/nephrectomy in accelerating mineralocorticoid-induced cardiac effects, we hypothesized that hypertensive heart disease is associated with oxidative stress and sensitizes the heart to mineralocorticoid, accelerating hypertrophy, fibrosis, and diastolic dysfunction.. Cardiac structure and function, oxidative stress, and mineralocorticoid receptor-dependent gene transcription were measured in sham-operated and transverse aortic constriction (studied 2 weeks later) mice without and with deoxycorticosterone acetate administration, all in the setting of normal-salt diet. Compared with sham mice, sham plus deoxycorticosterone acetate mice had mild hypertrophy without fibrosis or diastolic dysfunction. Transverse aortic constriction mice displayed compensated hypertensive heart disease with hypertrophy, increased oxidative stress (osteopontin and NOX4 gene expression), and normal systolic function, filling pressures, and diastolic stiffness. Compared with transverse aortic constriction mice, transverse aortic constriction plus deoxycorticosterone acetate mice had similar left ventricular systolic pressure and fractional shortening but more hypertrophy, fibrosis, and diastolic dysfunction with increased lung weights, consistent with heart failure with preserved ejection fraction. There was progressive activation of markers of oxidative stress across the groups but no evidence of classic mineralocorticoid receptor-dependent gene transcription.. Pressure-overload hypertrophy sensitizes the heart to mineralocorticoid excess, which promotes the transition to heart failure with preserved ejection fraction independently of classic mineralocorticoid receptor-dependent gene transcription.

Topics: Aldosterone; Animals; Atrial Natriuretic Factor; Capillaries; Collagen; Cytochrome b Group; Desoxycorticosterone; Heart Failure; Inflammation; Male; Membrane Glycoproteins; Mice; Mice, Inbred Strains; Mineralocorticoids; NADPH Oxidase 2; NADPH Oxidase 4; NADPH Oxidases; Osteopontin; Oxidative Stress; Reverse Transcriptase Polymerase Chain Reaction; RNA; RNA, Messenger; Stroke Volume; Ventricular Function, Left

Several new biomarkers are related to mortality in community-acquired pneumonia (CAP).. Aim of this study was to compare new biomarkers for the prediction of short- and long-term all-cause mortality in CAP.. We enrolled 728 patients (59.0 ± 18.2 yr) with CAP. Midregional proadrenomedullin (MR-proADM), midregional proatrial natriuretic peptide (MR-proANP), proarginin-vasopressin (copeptin), proendothelin-1 (CT-proET-1), procalcitonin (PCT), C-reactive protein, white blood cell (WBC) count, and clinical confusion, respiratory rate, blood pressure, and age over 65 years (CRB-65) score were determined on admission. Patients were followed up for 180 days.. In patients who died of any cause within 28 and 180 days (2.5 and 5.1%, respectively), MR-proADM, MR-proANP, copeptin, CT-proET-1 and PCT as well as CRB-65 were significantly higher compared with survivors. MR-proADM had the best performance for 28 days (HR 3.67) and 180 days (HR 2.84) survival. The C index of MR-proADM for 28-day survival (0.85) was superior to MR-proANP (0.81), copeptin (0.78), CT-proET-1 (0.79), and CRB-65 (0.72) for the prediction of mortality. For prediction of mortality at 180 days, the C index of MR-proADM (0.78) was higher than that for MR-proANP (0.74), copeptin (0.73), CT-proET-1 (0.76), PCT, C-reactive protein, and white blood cells. MR-proADM was independent of CRB-65, and added prognostic information for short- and long-term mortality. MR-proADM was an independent and strong predictor of short- and long-term mortality.. All new biomarkers were good predictors of short- and long-term all-cause mortality, superior to inflammatory markers, and at least comparable to CRB-65 score. MR-proADM showed the best performance. A combination of CRB-65 with MR-proADM might be the best predictor for mortality.

Topics: Adolescent; Adrenomedullin; Adult; Age Distribution; Aged; Aged, 80 and over; Atrial Natriuretic Factor; Biomarkers; Blood Pressure; C-Reactive Protein; Calcitonin; Calcitonin Gene-Related Peptide; Cardiovascular Diseases; Community-Acquired Infections; Comorbidity; Endothelin-1; Female; Germany; Humans; Inflammation; Leukocyte Count; Male; Middle Aged; Pneumonia; Predictive Value of Tests; Protein Precursors; Respiratory Rate; Survival Analysis; Vasopressins; Young Adult

Clinical studies suggest that intake of omega-3 polyunsaturated fatty acids (omega-3 PUFA) may lower the incidence of heart failure. Dietary supplementation with omega-3 PUFA exerts metabolic and anti-inflammatory effects that could prevent left ventricle (LV) pathology; however, it is unclear whether these effects occur at clinically relevant doses and whether there are differences between omega-3 PUFA from fish [eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)] and vegetable sources [alpha-linolenic acid (ALA)].. We assessed the development of LV remodelling and pathology in rats subjected to aortic banding treated with omega-3 PUFA over a dose range that spanned the intake of humans taking omega-3 PUFA supplements. Rats were fed a standard food or diets supplemented with EPA+DHA or ALA at 0.7, 2.3, or 7% of energy intake. Without supplementation, aortic banding increased LV mass and end-systolic and -diastolic volumes. ALA supplementation had little effect on LV remodelling and dysfunction. In contrast, EPA+DHA dose-dependently increased EPA and DHA, decreased arachidonic acid in cardiac membrane phospholipids, and prevented the increase in LV end-diastolic and -systolic volumes. EPA+DHA resulted in a dose-dependent increase in the anti-inflammatory adipokine adiponectin, and there was a strong correlation between the prevention of LV chamber enlargement and plasma levels of adiponectin (r = -0.78). Supplementation with EPA+DHA had anti-aggregatory and anti-inflammatory effects as evidenced by decreases in urinary thromboxane B(2) and serum tumour necrosis factor-alpha.. Dietary supplementation with omega-3 PUFA derived from fish, but not from vegetable sources, increased plasma adiponectin, suppressed inflammation, and prevented cardiac remodelling and dysfunction under pressure overload conditions.

Topics: Adenylate Kinase; Adiponectin; Animals; Atrial Natriuretic Factor; Dose-Response Relationship, Drug; Fatty Acids, Omega-3; Hypertension; Hypertrophy, Left Ventricular; Inflammation; Linseed Oil; Male; Myocardial Contraction; Myosin Heavy Chains; Phospholipids; Rats; Rats, Wistar; RNA, Messenger; Thromboxane B2; Tumor Necrosis Factor-alpha; Ventricular Function, Left; Ventricular Remodeling

Acute coronary artery occlusion triggers the release of atrial natriuretic peptide (ANP) from the heart. ANP affects vasodilation, natriuresis, and inflammation, but the integrated biological effects of ANP on myocardial infarction are unknown. To elucidate these effects, the left anterior coronary artery was ligated in anesthetized, ANP-deficient (ANP(-/-)) and congenic wild-type (ANP(+/+)) mice. The survival of ANP(-/-) mice was markedly better (56%) at 30 days postinfarction than the survival of ANP(+/+) mice (20%, P < 0.01). Surviving mice were comparable initially, but ANP(-/-) mice developed more cardiac hypertrophy (P < 0.001) and had lower contractility indexes 30 days after infarction (P < 0.05). An analysis 24 h after coronary occlusion showed that ANP(-/-) mice had smaller infarcts than ANP(+/+) mice (62.6 +/- 12.1 vs. 100.8 +/- 3.8%, P < 0.001) adjusted for comparable areas at risk for ischemia. The administration of ANP to ANP(-/-) mice via osmotic minipumps significantly enlarged infarct size to levels comparable with those observed in ANP(+/+) mice (P < 0.05). There was no difference in neutrophil migration into the noninfarcted myocardium of ANP(-/-) mice undergoing actual versus sham-operated coronary occlusion. By comparison, after coronary occlusion, the neutrophil infiltration into the myocardium was enhanced in ANP(+/+) (P < 0.0005) and ANP(-/-) mice administered ANP (P < 0.0005). The expression of P-selectin, a molecule that mediates neutrophil adhesion, was significantly greater after coronary occlusion in the vasculature of ANP(+/+) or ANP(-/-) mice treated with ANP than in ANP(-/-) mice (P < 0.002). Taken together, these results indicate that ANP increases P-selectin, neutrophil infiltration, infarct size, and mortality following experimental coronary occlusion.

Topics: Animals; Atrial Natriuretic Factor; Cardiomegaly; Coronary Occlusion; Disease Models, Animal; Hemodynamics; Inflammation; Infusion Pumps, Implantable; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Myocardial Contraction; Myocardial Infarction; Myocardium; Neutrophil Infiltration; P-Selectin; Time Factors

Hyperhomocysteinemia, neurohormonal activation, inflammation and altered fibrinolysis have been linked to atherothrombosis as well as to myocardial fibrosis and heart failure. Hence, we related a panel of biomarkers representing these pathways to plasma markers of collagen metabolism in a large community-based sample.. We related nine biomarkers representing select biologic pathways (independent variables: C-reactive protein, B-type natriuretic peptide, N-terminal proatrial natriuretic peptide, aldosterone, renin, fibrinogen, D-dimer, plasminogen activator inhibitor-1 and homocysteine) to three plasma markers of collagen turnover [dependent variables, separate models for each: aminoterminal propeptide of type III collagen, tissue inhibitor of metalloproteinases-1 and matrix metalloproteinase-9 (present versus absent)] in 921 Framingham Heart study participants (mean age 57 years; 58% women). Participants were separated a priori into those with left ventricular end-diastolic dimensions and wall thickness below sex-specific median values (referent group) and either measure at least 90th sex-specific percentile ('remodeled' group). We used stepwise multivariable regression analysis adjusting for cardiovascular risk factors to relate the panel of systemic biomarkers to the three biomarkers of collagen metabolism.. Plasma homocysteine was positively related to all three markers of collagen metabolism in the remodeled group and to aminoterminal propeptide of type III collagen and tissue inhibitor of metalloproteinases-1 in the referent group. Plasminogen activator inhibitor-1 was positively related to aminoterminal propeptide of type III collagen and tissue inhibitor of metalloproteinases-1 in both groups, whereas the natriuretic peptides were associated positively with these collagen markers in the referent group.. In our large community-based sample, plasma homocysteine and plasminogen activator inhibitor-1 were positively related to circulating collagen biomarkers, consistent with experimental studies implicating these pathways in cardiovascular collagen turnover.

Topics: Aged; Aldosterone; Atrial Natriuretic Factor; Biomarkers; C-Reactive Protein; Cardiovascular Diseases; Collagen; Collagen Type III; Cross-Sectional Studies; Data Collection; Female; Fibrin Fibrinogen Degradation Products; Fibrinogen; Fibrinolysis; Homocysteine; Humans; Inflammation; Male; Matrix Metalloproteinase 9; Middle Aged; Natriuretic Peptide, Brain; Plasminogen Activator Inhibitor 1; Protein Precursors; Renin; Renin-Angiotensin System; Tissue Inhibitor of Metalloproteinase-1; Ventricular Remodeling

Our objective was to study the effect of the genetic background on the wound healing process after myocardial infarction (MI) in mice.. MI was induced in five different mouse strains (BalbC, C57Bl6, FVB, 129S6, and Swiss). At 3, 14, and 28 days after MI, cardiac dimensions were monitored by echocardiography and histology, whereas cardiac function was determined by direct intraventricular pressure measurements (dP/dt). Furthermore, matrix metalloproteinases were measured by zymography, and mRNA expression by quantitative PCR. Infarct rupture, which typically occurred at 3-6 days post-MI, was most frequent in 129S6 mice (62%), followed by C57Bl6 (36%), FVB (29%), Swiss (23%), and BalbC (5%). The high incidence of infarct rupture in 129S6 mice was associated with high systolic blood pressure and increased influx of inflammatory cells. Cardiac dilatation was most marked in Swiss mice and least prominent in 129S6 mice. The degree of dilatation was associated with a reduced ejection fraction and decreased dP/dt values at 14 and 28 days post-MI. At day 14 and 28 post-MI, secondary thinning of the infarct area was marked in BalbC, FVB, and Swiss, but absent in C57Bl6 and 129S6 mice. In the latter two groups, this was paralleled by the highest number of myofibroblasts at day 14 post-MI.. The outcome of infarct healing in mice strongly depends on genetic background. On the basis of our results, we suggest that for studies on infarct rupture, the 129S6 mouse is the background of choice, whereas BalbC and Swiss mice are the preferred models to study infarct thinning post-MI.

Topics: Animals; Antihypertensive Agents; Atrial Natriuretic Factor; Blood Pressure; Disease Models, Animal; Echocardiography; Gene Expression Regulation, Enzymologic; Heart Rupture, Post-Infarction; Inflammation; Male; Matrix Metalloproteinases; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Myocardial Infarction; Myocardium; Natriuretic Peptide, Brain; Polymerase Chain Reaction; RNA, Messenger; Species Specificity; Stroke Volume; Time Factors; Ventricular Function, Left; Ventricular Pressure; Wound Healing

Topics: Amyloidosis; Atrial Fibrillation; Atrial Natriuretic Factor; Heart Atria; Humans; Inflammation; Time Factors

Activated neutrophils have been implicated in the development of ischemia/reperfusion (I/R)-induced renal failure. Cytokine-induced neutrophil chemoattractant-1 (CINC-1), a major factor in acute inflammation, is responsible for the activation of neutrophils and for neutrophil chemotaxis to sites of injury. Atrial natriuretic peptide (ANP), a hormone synthesized by the cardiac atria, was shown to possess anti-inflammatory potential due to its potency to inhibit the production of inflammatory mediators. We examined whether the human form of ANP attenuates I/R-induced renal injury by reducing neutrophil activation in a rat model. Male Wistar rats weighing 200-240 g were observed for 24 h after reperfusion following 45-min renal ischemia. Rats were intravenously administered alpha-human ANP (alpha-hANP, 0.2 microg/kg/min) beginning immediately after ischemia and continuing for 2 h after reperfusion. CINC-1 and myeloperoxidase (MPO) concentrations were measured to assess activation of the infiltrating neutrophil. Blood urea nitrogen and serum creatinine and urinary N-acetyl beta-d-glucosaminidase (NAG) were measured as indicators of glomerular function and as a specific indicator of proximal tubular function, respectively. alpha-hANP significantly inhibited I/R-induced increases in renal CINC-1 and MPO concentrations. alpha-hANP also reduced I/R-induced increases in the concentrations of blood urea nitrogen and serum creatinine, and improved histopathologic changes, including acute tubular necrosis. These findings indicate that alpha-hANP attenuates I/R-induced acute renal injury, at least in part by reducing neutrophil activation, and may be useful in surgeries, associated with renal ischemia, as well as in renal transplantation.

Topics: Animals; Atrial Natriuretic Factor; Chemokine CXCL1; Creatinine; Hexosaminidases; Inflammation; Kidney; Male; Models, Biological; Neutrophil Activation; Neutrophils; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

We hypothesized that intracoronary adenoviral-mediated delivery of betaARKct would improve heart failure associated pathophysiologic abnormalities related to exercise capacity, cardiac contractility, systemic inflammation and volume overload.. After aortic banding, a cohort of Sprague-Dawley rats was followed by echocardiography. When an absolute decline of 25% in fractional shortening was detected, animals were randomized to intracoronary delivery of Ad.ssARKct (n=14), Ad.beta-Gal (n=13), or followed without any other further intervention (n=18). Assessment of exercise tolerance and hemodynamic profile and measurement of markers of systemic inflammation and volume overload was performed at 7, 14, and 21 days after gene delivery. Data were analyzed using ANOVA.. Animals receiving Ad.ssARKct showed improved exercise tolerance compared to Ad.Gal-treated animals at 14 days (507+/-26 s vs. 408+/-19 s, P=0.01) and 21 days (526+/-55 s vs. 323+/-19 s, P<0.001) following injection. Animals receiving Ad.ssARKct demonstrated improved +dP/dtmax (mean+/-SD, 5,581+/-960 mmHg/s vs. 3,134+/-438 mmHg/s, P<0.01) and -dP/dtmax (mean+/-SD, -3,494+/-1,269 mmHg/s vs. -1,925+/-638 mmHg/s, P<0.01) compared to Ad.Gal-treated animals at 7 days. These differences were observed up to 21 days following injection. Serum levels of IL-1, IL-6, and TNF-alpha, as well as ANP were also decreased in animals receiving Ad.betaARKct.. Genetic modulation of heart failure using the betaARKct gene was associated with improved exercise capacity and cardiac function as well as amelioration in heart failure-associated profiles of systemic inflammation and volume overload.

Topics: Adenoviridae; Analysis of Variance; Animals; Atrial Natriuretic Factor; Blotting, Western; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Gene Transfer Techniques; Genetic Therapy; Genetic Vectors; Heart Failure; Hemodynamics; Hypertrophy, Left Ventricular; Inflammation; Interleukin-1; Interleukin-6; Male; Myocardial Contraction; Natriuretic Peptides; Peptides; Physical Conditioning, Animal; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Tumor Necrosis Factor-alpha

Natriuretic peptides (NPs) comprise a family of vasoactive hormones that play important roles in the regulation of cardiovascular and renal homeostasis. Along this line, atrial NP (ANP) (international non-proprietary name: carperitide, HANP) is an approved drug for the treatment of acute heart failure. In recent years, evidence has been given that the NP system possesses a far broader biological spectrum than the regulation of blood pressure and volume homeostasis. In fact, a substantial amount of in vitro work indicates that ANP affects important inflammatory processes and signaling pathways. Quite surprisingly, however, no information exists on the in vivo antiinflammatory potential and signaling of ANP. We show here that pretreatment of lipopolysaccharide (Salmonella abortus equi, 2.5 mg/kg)-challenged mice with ANP (5 microg/kg iv, 15 min) rapidly inhibits nuclear factor-kappaB activation via inhibition of phosphorylation and degradation of the IkappaB-alpha protein. ANP also reduces Akt activation upon lipopolysaccharide injection. In ANP-pretreated mice, the increase of TNF-alpha serum concentration is markedly prevented; most importantly, the survival of these animals improved. These findings demonstrate both in vitro and in vivo an antiinflammatory profile of ANP that deserves to be further investigated in a therapeutic perspective.

Topics: Animals; Atrial Natriuretic Factor; I-kappa B Proteins; Inflammation; Inflammation Mediators; Lipopolysaccharides; Male; Mice; Mice, Inbred BALB C; NF-kappa B; NF-KappaB Inhibitor alpha; Proto-Oncogene Proteins c-akt; RNA, Messenger; Survival Rate; Tumor Necrosis Factor-alpha

Increased adipose tissue secretion of adipokines and cytokines has been implicated in the chronic low-grade inflammation state and insulin resistance associated with obesity. We tested here whether the cardiovascular and metabolic hormone atrial natriuretic peptide (ANP) was able to modulate adipose tissue secretion of several adipokines (derived from adipocytes) and cytokines (derived from adipose tissue macrophages).. We used protein array to measure the secretion of adipokines and cytokines after a 24-h culture of human subcutaneous adipose tissue pieces treated or not with a physiological concentration of ANP. The effect of ANP on protein secretion was also directly studied on isolated adipocytes and macrophages. Gene expression was measured by real-time RT-quantitative PCR.. ANP decreased the secretion of the pro-inflammatory cytokines IL-6 and TNF-alpha, of several chemokines, and of the adipokines leptin and retinol-binding protein-4 (RBP-4). The secretion of the anti-inflammatory molecules IL-10 and adiponectin remained unaffected. The cytokines were mainly expressed in macrophages that expressed all components of the ANP-dependent signalling pathway. The adipokines, leptin, adiponectin and RBP-4 were specifically expressed in mature adipocytes. ANP directly inhibited the secretion of IL-6 and monocyte chemoattractant protein-1 by macrophages. The inhibitory effects of ANP on leptin and growth-related oncogene-alpha secretions were not seen under selective hormone-sensitive lipase inhibition.. We suggest that ANP, either by direct action on adipocytes and macrophages or through activation of adipocyte hormone-sensitive lipase, inhibits the secretion of factors involved in inflammation and insulin resistance.

Topics: Abdomen; Adipocytes; Adiponectin; Adipose Tissue; Adult; Atrial Natriuretic Factor; Cells, Cultured; Cytokines; Female; Humans; Inflammation; Insulin Resistance; Macrophages; Middle Aged; Overweight; Polymerase Chain Reaction; RNA

We have previously demonstrated that inflammatory compounds that increase nitric oxide (NO) synthase expression have a biphasic effect on the level of the NO messenger cGMP in astrocytes. In this work, we demonstrate that NO-dependent cGMP formation is involved in the morphological change induced by lipopolysaccharide (LPS) in cultured rat cerebellar astroglia. In agreement with this, dibutyryl-cGMP, a permeable cGMP analogue, and atrial natriuretic peptide, a ligand for particulate guanylyl cyclase, are both able to induce process elongation and branching in astrocytes resulting from a rapid, reversible and concentration-dependent redistribution of glial fibrillary acidic protein (GFAP) and actin filaments without significant change in protein levels. These effects are also observed in astrocytes co-cultured with neurons. The cytoskeleton rearrangement induced by cGMP is prevented by the specific protein kinase G inhibitor Rp-8Br-PET-cGMPS and involves downstream inhibition of RhoA GTPase since is not observed in cells transfected with constitutively active RhoA. Furthermore, dibutyryl-cGMP prevents RhoA-membrane association, a step necessary for its interaction with effectors. Stimulation of the cGMP-protein kinase G pathway also leads to increased astrocyte migration in an in vitro scratch-wound assay resulting in accelerated wound closure, as seen in reactive gliosis following brain injury. These results indicate that cGMP-mediated pathways may regulate physio-pathologically relevant responses in astroglial cells.

Topics: Actins; Animals; Antimetabolites; Astrocytes; Atrial Natriuretic Factor; Blotting, Western; Bromodeoxyuridine; Bucladesine; Cell Movement; Cells, Cultured; Cyclic GMP-Dependent Protein Kinases; Cytoskeleton; Fluorescent Dyes; Glial Fibrillary Acidic Protein; Indoles; Inflammation; Lipopolysaccharides; Neuroglia; Nitric Oxide; Phenotype; Rats; Rats, Sprague-Dawley; rhoA GTP-Binding Protein; Signal Transduction; Transfection; Wounds and Injuries

Endothelial dysfunction is a critical intermediate phenotype in the pathogenesis of cardiovascular disease. We evaluated the relative contributions of distinct biological pathways to interindividual variation in endothelial function by relating prototype biomarkers (representing these pathways) to brachial artery vasodilator function.. We investigated the cross-sectional relations of a panel of 7 biomarkers measured at a routine examination to brachial artery vasodilator function (flow-mediated dilation [FMD] and reactive hyperemia) assessed at a subsequent examination (mean interval, 2.9 years) in 2113 Framingham Heart Study participants (mean age, 61 years; 54% women). We selected biomarkers from 4 biological domains: neurohormonal (N-terminal pro-atrial natriuretic peptide [N-ANP], B-type natriuretic peptide [BNP], renin, aldosterone), hemostatic factors (plasminogen activator inhibitor-1 [PAI-1]), inflammation (C-reactive protein [CRP]), and target organ damage (urine albumin-creatinine ratio). In age- and sex-adjusted models, several biomarkers were related to baseline brachial artery diameter (PAI-1, CRP, urine albumin-creatinine ratio), baseline mean flow (N-ANP, BNP, PAI-1, CRP, aldosterone), FMD (N-ANP, PAI-1, CRP, renin), and reactive hyperemia (BNP, PAI-1, CRP, renin, urine albumin-creatinine ratio). In multivariable analyses relating the 7 biomarkers conjointly to each vascular function measure (adjusting for known risk factors), N-ANP and renin were positively related to FMD (P=0.001 and P=0.04, respectively), and N-ANP was inversely related to baseline mean flow velocity (P=0.01). None of the other biomarkers was significantly related to the vascular function measures studied.. In our large community-based sample, a conservative strategy relating several biomarkers to vascular endothelial function identified plasma N-ANP as a key correlate of mean flow under basal conditions and of FMD in response to forearm cuff occlusion.

Topics: Aged; Atrial Natriuretic Factor; Biomarkers; Brachial Artery; Cross-Sectional Studies; Endothelium, Vascular; Female; Humans; Hyperemia; Inflammation; Male; Middle Aged; Regional Blood Flow; Vasodilation

In patients with congestive heart failure, high serum levels of the proinflammatory cytokine interleukin (IL)-18 were reported. A positive correlation was described between serum IL-18 levels and the disease severity. IL-18 has also been shown to induce atrial natriuretic factor (ANF) gene expression in adult cardiomyocytes. Because re-expression of the fetal gene ANF is mostly associated with hypertrophy, a hallmark of heart failure, we hypothesized that IL-18 induces cardiomyocyte hypertrophy. Treatment of the cardiomyocyte cell line HL-1 with IL-18 induced hypertrophy as characterized by increases in protein synthesis, phosphorylated p70 S6 kinase, and ribosomal S6 protein levels as well as cell surface area. Furthermore, IL-18 induced ANF gene transcription in a time-dependent manner as evidenced by increased ANF secretion and ANF promoter-driven reporter gene activity. Investigation into possible signal transduction pathways mediating IL-18 effects revealed that IL-18 activates phosphoinositide 3-kinase (PI3K), an effect that was blocked by wortmannin and LY-294002. IL-18 induced Akt phosphorylation and stimulated its activity, effects that were abolished by Akt inhibitor or knockdown. IL-18 stimulated GATA4 DNA binding activity and increased transcription of a reporter gene driven by multimerized GATA4-binding DNA elements. Pharmacological inhibition or knockdown studies revealed that IL-18 induced cardiomyocyte hypertrophy and ANF gene transcription via PI3K, PDK1, Akt, and GATA4. Most importantly, IL-18 induced ANF gene transcription and hypertrophy of neonatal rat ventricular myocytes via PI3K-, Akt-, and GATA4-dependent signaling. Together these data provide the first evidence that IL-18 induces cardiomyocyte hypertrophy via PI3K-dependent signaling, defines a mechanism of IL-18-mediated ANF gene transcription, and further supports a role for IL-18 in inflammatory heart diseases including heart failure.

Topics: Androstadienes; Animals; Atrial Natriuretic Factor; Blotting, Northern; Blotting, Western; Cell Line; Cell Nucleus; Cells, Cultured; Chromones; Cytokines; DNA; DNA-Binding Proteins; Enzyme Activation; Enzyme Inhibitors; GATA4 Transcription Factor; Gene Expression Regulation; Genes, Reporter; Hypertrophy; Inflammation; Interleukin-18; Interleukin-18 Receptor alpha Subunit; Mice; Morpholines; Myocytes, Cardiac; Phenotype; Phosphatidylinositol 3-Kinases; Phosphorylation; Promoter Regions, Genetic; Protein Binding; Protein Serine-Threonine Kinases; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-akt; Rats; Receptors, Interleukin; Receptors, Interleukin-18; Ribosomal Protein S6 Kinases, 70-kDa; Signal Transduction; Time Factors; Transcription Factors; Transcription, Genetic; Transfection; Wortmannin

Cardiac hypertrophy is a complex and nonhomogenous response to various stimuli. In this study, we used high-density oligonucleotide microarray to examine gene expression profiles during physiological hypertrophy, pathological hypertrophy, and heart failure in Dahl salt-sensitive rats. There were changes in 404/3,160 and 874/3,160 genes between physiological and pathological hypertrophy and the transition from hypertrophy to heart failure, respectively. There were increases in stress response genes (e.g., heat shock proteins) and inflammation-related genes (e.g., pancreatitis-associated protein and arachidonate 12-lipoxygenase) in pathological processes but not in physiological hypertrophy. Furthermore, atrial natriuretic factor and brain natriuretic protein showed distinctive changes that are very specific to different conditions. In addition, we used a resampling-based gene score-calculating method to define significantly altered gene clusters, based on Gene Ontology classification. It revealed significant alterations in genes involved in the apoptosis pathway during pathological hypertrophy, suggesting that the apoptosis pathway may play a role during the transition to heart failure. In addition, there were significant changes in glucose/insulin signaling, protein biosynthesis, and epidermal growth factor signaling during physiological hypertrophy but not during pathological hypertrophy.

Topics: Animals; Apoptosis; Atrial Natriuretic Factor; Blotting, Northern; Cardiomegaly; Echocardiography; Epidermal Growth Factor; Gene Expression Profiling; Gene Expression Regulation; Heart Failure; Hypertrophy; Inflammation; Insulin; Natriuretic Peptide, Brain; Oligonucleotide Array Sequence Analysis; Pancreatitis-Associated Proteins; Physical Conditioning, Animal; Rats; Rats, Inbred Dahl; RNA; Signal Transduction

The multifaceted process of immune cell recruitment to sites of tissue injury is key to the development of an inflammatory response and involved in the pathogenesis of numerous cardiovascular disorders. We recently identified C-type natriuretic peptide (CNP) as an important endothelium-derived mediator that regulates vascular tone and protects against myocardial ischemia/reperfusion injury. Herein, we investigated whether CNP inhibits leukocyte recruitment and platelet aggregation and thereby exerts a potential antiinflammatory influence on the blood vessel wall. We assessed the effects of CNP on leukocyte-endothelial cell interactions in mouse mesenteric postcapillary venules in vivo in animals with high basal leukocyte activation (endothelial nitric oxide synthase knockout mice, eNOS(-/-)) or under acute inflammatory conditions (induced by interleukin-1beta or histamine). CNP suppressed basal leukocyte rolling in eNOS(-/-) mice in a rapid, reversible, and concentration-dependent manner. These effects of CNP were mimicked by the selective natriuretic peptide receptor-C agonist cANF(4-23). CNP also suppressed leukocyte rolling induced by IL-1beta or histamine, inhibited platelet-leukocyte interactions, and prevented thrombin-induced platelet aggregation of human blood. Furthermore, analysis of human umbilical vein endothelial cells, leukocytes, and platelets revealed that CNP selectively attenuates expression of P-selectin. Thus, CNP is a modulator of acute inflammation in the blood vessel wall characterized by leukocyte and platelet activation. These antiinflammatory effects appear to be mediated, at least in part, via suppression of P-selectin expression. These observations suggest that endothelial CNP might maintain an anti-atherogenic influence on the blood vessel wall and represent a target for therapeutic intervention in inflammatory cardiovascular disorders.

Topics: Analysis of Variance; Animals; Atrial Natriuretic Factor; Endothelium, Vascular; Flow Cytometry; Gene Expression Regulation; Humans; Inflammation; Leukocytes; Mice; Mice, Knockout; Natriuretic Peptide, C-Type; Nitric Oxide Synthase Type II; Nitric Oxide Synthase Type III; P-Selectin; Peptide Fragments; Platelet Aggregation; Venules

Natriuretic peptides (NPs), which consist of atrial, brain, and C-type natriuretic peptides (ANP, BNP, and CNP, respectively), are characterized as cardiac or vascular hormones that elicit their biological effects by activation of the cGMPcGMP-dependent protein kinase (cGK) pathway. We recently reported that adenoviral gene transfer of CNP into rabbit blood vessels not only suppressed neointimal formation but also accelerated reendothelialization, a required step for endothelium-dependent vasorelaxation and antithrombogenicity. Accordingly, we investigated the therapeutic potential of the NPscGMPcGK pathway for vascular regeneration. In transgenic (Tg) mice that overexpress BNP in response to hindlimb ischemia, neovascularization with appropriate mural cell coating was accelerated without edema or bleeding, and impaired angiogenesis by the suppression of nitric oxide production was effectively rescued. Furthermore, in BNP-Tg mice, inflammatory cell infiltration in ischemic tissue and vascular superoxide production were suppressed compared with control mice. Ischemia-induced angiogenesis was also significantly potentiated in cGK type I Tg mice, but attenuated in cGK type I knockout mice. NPs significantly stimulated capillary network formation of cultured endothelial cells by cGK stimulation and subsequent Erk12 activation. Furthermore, gene transfer of CNP into ischemic muscles effectively accelerated angiogenesis. These findings reveal an action of the NPscGMPcGK pathway to exert multiple vasculoprotective and regenerative actions in the absence of apparent adverse effects, and therefore suggest that NPs as the endogenous cardiovascular hormone can be used as a strategy of therapeutic angiogenesis in patients with tissue ischemia.

Topics: Animals; Atrial Natriuretic Factor; Blood Vessels; Cells, Cultured; Cyclic GMP; Cyclic GMP-Dependent Protein Kinases; Gene Expression; Gene Transfer Techniques; Humans; Inflammation; Ischemia; Mice; Mice, Knockout; Mice, Transgenic; Natriuretic Peptide, Brain; Natriuretic Peptide, C-Type; Neovascularization, Physiologic; Regeneration

Topics: Angioplasty, Balloon, Coronary; Atrial Natriuretic Factor; C-Reactive Protein; Carotid Artery Diseases; Clinical Trials as Topic; Combined Modality Therapy; Coronary Disease; Electrocardiography; Heart Failure; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Inflammation; Myocardial Revascularization; Natriuretic Peptide, Brain; Stents

Topics: Acute Disease; Atrial Natriuretic Factor; Biomarkers; C-Reactive Protein; Coronary Disease; Creatinine; Glycated Hemoglobin; Humans; Inflammation; Kidney Diseases; Natriuretic Peptide, Brain; Predictive Value of Tests; Prognosis; Risk Assessment; Risk Factors; Syndrome

A peripheral 5-HT(2A) receptor-mediated hemodynamic change prompted formation of indole-2,3-dione, an endogenous inhibitor of atrial natriuretic peptide (ANP) receptor binding and G protein-mediated intracellular signaling (IC(50): 0.4 microM). This effect was significantly suppressed by dexamethasone, indomethacin and the 5-HT(2) receptor antagonists, ketanserin or ritanserin. 5-HT(2A) receptor-mediated acute hemodynamic change was not modified significantly by indomethacin, prazosin or propranolol pretreatment. A tyrosine hydroxylase inhibitor, alpha-methyl-p-tyrosine, but not a dopamine beta hydroxylase inhibitor, diethyldithiocarbamate, abolished the 5-HT(2A) receptor-mediated increase in indole-2,3-dione. Exogenous indole-2,3-dione induced a significant increase in plasma catecholamine levels and decrease in urine volume. A 5-HT(2A) receptor-mediated decrease in capillary flow may have caused an inflammatory process and peripheral sympathetic activation via ANP signaling inhibition. 3,4-dihydroxyphenylalanine (DOPA)/dopamine may contribute to the progression of inflammation or the generation of a precursor of indole-2,3-dione. The observation that indole-2,3-dione abolished angiotensin AT(1) receptor-mediated NADPH activation in both human umbilical vein endothelial cells and smooth muscle cells at 20 microM may suggest that sulfhydryl-reactive indole-2,3-dione could influence mitochondrial function and cellular redox states via flavoenzyme inhibition and/or regulation of dehydrogenase-oxidase conversion.

Topics: Adrenergic alpha-Antagonists; alpha-Methyltyrosine; Animals; Atrial Natriuretic Factor; Catecholamines; Cyclooxygenase Inhibitors; Dexamethasone; Ditiocarb; Dopamine beta-Hydroxylase; Dose-Response Relationship, Drug; Endothelium, Vascular; Humans; Indomethacin; Inflammation; Isatin; Ketanserin; Muscle, Smooth; Prazosin; Propranolol; Protein Binding; Rats; Rats, Wistar; Reactive Oxygen Species; Receptor, Angiotensin, Type 1; Receptor, Serotonin, 5-HT2A; Receptors, Angiotensin; Receptors, Serotonin; Reserpine; Ritanserin; Serotonin; Serotonin Receptor Agonists; Tyrosine 3-Monooxygenase; Urination; Vascular Resistance; Yohimbine

We experienced four cases with hyponatremia due to SIADH, which seems to be related to inflammation. The plasma Na concentration decreased when the patients had fever and increased plasma CRP level. In such conditions, plasma vasopressin concentration (PAVP) and the plasma interleukin-6 (IL-6) concentration were increased. There was significant correlation between them. The animal experiments were carried out to investigate the role of interleukin in the development of SIADH. Intravenous administrations of IL-1 beta increased AVP, atrial natriuretic hormone (ANH) and ACTH. The changes in AVP and ACTH were abolished by the pretreatment with an intravenous administration of indomatacin. Moreover, the intracerebroventricular administration (ICV) of IL-1 beta also increased AVP, atrial natriuretic hormone (ANH) and ACTH. The pretreatment of indomatacin attenuated the changes in AVP and ACTH. The intravenous administration of IL-1 beta increased the urinary sodium excretion. The pretreatement of HS142-1, an ANH antagonist, abolished the increase in urinary sodium excretion induced by IL-1 beta. These results suggested that the interleukin play an important role in the development of SIADH associated with inflammation.

Topics: Adrenocorticotropic Hormone; Adult; Aged; Aged, 80 and over; Animals; Atrial Natriuretic Factor; Female; Humans; Hyponatremia; Inappropriate ADH Syndrome; Inflammation; Interleukin-1; Interleukin-6; Male; Rats; Rats, Sprague-Dawley; Vasopressins

Capillary barrier function is subject to changes in Starling forces via hemodynamic status (hydrostatic pressure) or protein milieu of fluids bathing the wall (oncotic pressure). Venular function is sensitive to inflammatory mediators leading to white cell sticking, fluid and formed element extravasation, and flow disruption. Thus, we hypothesized that vasoactive hormones and autocrines alter preferentially the venular-capillary (VC) barrier. Hydraulic conductivity (Lp) of frog mesenteric venular- and true-capillaries (TC) was measured by the modified-Landis technique under control (LpC), then during atrial natriuretic peptide (ANP, 10(-7) to 10(-8) M), bradykinin (BKN, 10(-7) M), acetylcholine (ACh, 10(-6) to 10(-5) M), angiotensin II (AII, 10(-7) M), or norepinephrine (NE, 10(-6) M) perfusion. All agents, except AII or NE, elevated Lp: LpANP/LpC = 2.9 +/- 0.3 (mean +/- SEM; (n = 55), LpBKN/LpC = 3.3 +/- 0.8 (n = 16), LpACh/LpC = 1.6 +/- 0.1 (n = 26), LpAII/LpC = 1.1 +/- 0.2 (n = 8), and LpNE/LpC = 1.1 +/- 0.2 (n = 9). Contrary to our hypothesis, VC and TC responded similarly: 3.0 versus 2.9 for ANP, 3.4 versus 3.2 for BKN, and 1.6 versus 1.6 for ACh, respectively. These data are consistent with putative vasodilators lowering capillary barrier resistance independent from changes in Starling forces.

Topics: Acetylcholine; Angiotensin II; Animals; Atrial Natriuretic Factor; Bradykinin; Capillaries; Humans; Hydrostatic Pressure; In Vitro Techniques; Inflammation; Models, Cardiovascular; Muscle, Smooth, Vascular; Norepinephrine; Pressure; Rana pipiens; Recombinant Proteins; Splanchnic Circulation; Vasoconstriction; Vasodilator Agents; Venules

Serum levels of various cytokines were measured in three patients with cardiac myxomas presenting with and without constitutional symptoms, immunological features and elevated plasma levels of interleukin-6. Interleukin-6 but not other cytokines (interleukin-1, tumour necrosis factor-alpha, interferon-gamma) relate to immunological features of the patients. Circulating levels of atrial natriuretic peptide correspond to haemodynamic changes but not to the tumour-bearing state itself.

Topics: Atrial Natriuretic Factor; Biopterins; Cytokines; Heart Neoplasms; Humans; Inflammation; Interleukin-6; Myxoma; Neopterin

Water immersion induced alterations of plasma atrial natriuretic peptide (ANP), circulating plasma volume (PV), plasma sodium and potassium and mean blood pressure (MAP) were examined in 12 patients with non-inflammatory acute renal failure (ARF) and in 15 healthy subjects. In patients with ARF a significantly elevated basal ANP (139 +/- 13 pg/ml versus 75 +/- 4 pg/ml in normals) and elevated MAP (112 +/- 3.5 mmHg versus 87 +/- 2 mmHg in normals) were found. Water immersion induced a significant increase in plasma ANP in both groups, which was significantly more marked in healthy subjects (152 +/- 13 pg/ml) than in patients with ARF (86 +/- 13 pg/ml). Water immersion was accompanied by a significantly more marked reduction of MAP (23 +/- 3 mmHg) and plasma sodium (6.1 +/- 0.6 mmol/l) in patients with ARF than in normals (12.7 +/- 1.5 mmHg and 4.2 +/- 0.1 mmol/l respectively). In contrast to healthy subjects, in patients with ARF water immersion did not induce enhanced diuresis. In patients with ARF a significantly more marked increase in plasma volume was found than in normals. Data obtained in this study seem to prove preservation of the physiological regulatory mechanism of ANP secretion in ARF patients but reduction of ANP release induced by central volume expansion. The importance of elevated basal plasma values in the maintenance of ARF has not been proven.

Topics: Acute Kidney Injury; Adult; Atrial Natriuretic Factor; Blood Pressure; Diuresis; Female; Humans; Immersion; Inflammation; Male; Plasma Volume; Potassium; Sodium