atrial-natriuretic-factor and Systemic-Inflammatory-Response-Syndrome

The present review will cover the mechanisms of release and the potential pathophysiological role of different natriuretic peptides in critically ill patients. By focusing on the cardiovascular system, possible implications of natriuretic peptides for diagnosis and treatment will be presented. In critical illness such as sepsis, trauma or major surgery, systemic hypotension and an intrinsic myocardial dysfunction occur. Impairment of the cardiovascular system contributes to poor prognosis in severe human sepsis. Natriuretic peptides have emerged as valuable marker substances to detect left ventricular dysfunction in congestive heart failure of different origins. Increased plasma levels of circulating natriuretic peptides, atrial natriuretic peptide, N-terminal pro-atrial natriuretic peptide, brain natriuretic peptide and its N-terminal moiety N-terminal pro-brain natriuretic peptide have also been found in critically ill patients. All of these peptides have been reported to reflect left ventricular dysfunction in these patients. The increased wall stress of the cardiac atria and ventricles is followed by the release of these natriuretic peptides. Furthermore, the release of atrial natriuretic peptide and brain natriuretic peptide might be triggered by members of the IL-6-related family and endotoxin in the critically ill. Apart from the vasoactive actions of circulating natriuretic peptides and their broad effects on the renal system, anti-ischemic properties and immunological functions have been reported for atrial natriuretic peptide. The early onset and rapid reversibility of left ventricular impairment in patients with good prognosis associated with a remarkably augmented plasma concentration of circulating natriuretic peptides suggest a possible role of these hormones in the monitoring of therapy success and the estimation of prognosis in the critically ill.

Topics: Atrial Natriuretic Factor; Critical Illness; Humans; Intensive Care Units; Natriuretic Peptide, Brain; Prognosis; Systemic Inflammatory Response Syndrome; Ventricular Dysfunction, Left; Wounds and Injuries

Most early preterm births are associated with intraamniotic infection and inflammation, which can lead to systemic inflammation in the fetus. The fetal inflammatory response syndrome describes elevations in the fetal interleukin-6 level, which is a marker for inflammation and fetal organ injury. An understanding of the effects of inflammation on fetal cardiac development may lead to insight into the fetal origins of adult cardiovascular disease.. The purpose of this study was to determine whether the fetal inflammatory response syndrome is associated with disruptions in gene networks that program fetal cardiac development.. We obtained fetal cardiac tissue after necropsy from a well-described pregnant nonhuman primate model (pigtail macaque, Macaca nemestrina) of intrauterine infection (n=5) and controls (n=5). Cases with the fetal inflammatory response syndrome (fetal plasma interleukin-6 >11 pg/mL) were induced by either choriodecidual inoculation of a hypervirulent group B streptococcus strain (n=4) or intraamniotic inoculation of Escherichia coli (n=1). RNA and protein were extracted from fetal hearts and profiled by microarray and Luminex (Millipore, Billerica, MA) for cytokine analysis, respectively. Results were validated by quantitative reverse transcriptase polymerase chain reaction. Statistical and bioinformatics analyses included single gene analysis, gene set analysis, Ingenuity Pathway Analysis (Qiagen, Valencia, CA), and Wilcoxon rank sum.. Severe fetal inflammation developed in the context of intraamniotic infection and a disseminated bacterial infection in the fetus. Interleukin-6 and -8 in fetal cardiac tissues were elevated significantly in fetal inflammatory response syndrome cases vs controls (P<.05). A total of 609 probe sets were expressed differentially (>1.5-fold change, P<.05) in the fetal heart (analysis of variance). Altered expression of select genes was validated by quantitative reverse transcriptase polymerase chain reaction that included several with known functions in cardiac injury, morphogenesis, angiogenesis, and tissue remodeling (eg, angiotensin I converting enzyme 2, STEAP family member 4, natriuretic peptide A, and secreted frizzled-related protein 4; all P<.05). Multiple gene sets and pathways that are involved in cardiac morphogenesis and vasculogenesis were downregulated significantly by gene set and Ingenuity Pathway Analysis (hallmark transforming growth factor beta signaling, cellular morphogenesis during differentiation, morphology of cardiovascular system; all P<.05).. Disruption of gene networks for cardiac morphogenesis and vasculogenesis occurred in the preterm fetal heart of nonhuman primates with preterm labor, intraamniotic infection, and severe fetal inflammation. Inflammatory injury to the fetal heart in utero may contribute to the development of heart disease later in life. Development of preterm labor therapeutics must also target fetal inflammation to lessen organ injury and potential long-term effects on cardiac function.

Topics: Angiotensin-Converting Enzyme 2; Animals; Atrial Natriuretic Factor; Biomarkers; Chorioamnionitis; Down-Regulation; Female; Fetal Diseases; Heart; Interleukin-6; Interleukin-8; Macaca nemestrina; Membrane Proteins; Microarray Analysis; Models, Animal; Myocardium; Obstetric Labor, Premature; Oxidoreductases; Peptidyl-Dipeptidase A; Pregnancy; Proto-Oncogene Proteins; Reverse Transcriptase Polymerase Chain Reaction; Systemic Inflammatory Response Syndrome; Up-Regulation

The aim of this study was to determine whether systemic inflammatory response syndrome (SIRS) in burn patients is mediated by the brain natriuretic peptide (BNP)/natriuretic peptide A receptor (NPRA)-induced heat shock factor 1 (HSF-1) signalling pathway. Mononuclear cells (MNCs) that were isolated from patients with burn injuries and SIRS mouse models and a RAW264.7 cell line were treated with normal serum or serum obtained from animals with burn injuries. In parallel, small hairpin RNAs (shRNAs) against BNP or NPRA were transfected in both cell types. Western blotting (WB) and enzyme-linked immunosorbent assay (ELISA) were used to detect protein expression and inflammatory factor levels, respectively. We found that interleukin (IL)-12, tumour necrosis factor (TNF)-α, C-reactive protein (CRP), and BNP levels were increased and IL-10 levels were decreased in the plasma and MNCs in vivo in the animal model of SIRS. Additionally, NPRA was upregulated, whereas HSF-1 was downregulated in monocytes in vivo. Treatment of RAW264.7 cells with burn serum or BNP induced IL-12, TNF-α, and CRP secretion as well as HSF-1 expression. Finally, silencing BNP with shRNA interrupted the effect of burn serum on RAW264.7 cells, and silencing NPRA blocked burn serum- and BNP-mediated changes in RAW264.7 cells. These results suggest that the interaction of NPRA with BNP secreted from circulatory MNCs as well as mononuclear macrophages leads to inflammation via HSF-1 during SIRS development following serious burn injury.

Topics: Animals; Atrial Natriuretic Factor; Biomarkers; Burns; Cell Line; DNA-Binding Proteins; Heat Shock Transcription Factors; Male; Mice; Mice, Inbred C57BL; Natriuretic Peptide, Brain; Natriuretic Peptide, C-Type; Protein Precursors; Rats; Rats, Sprague-Dawley; Signal Transduction; Systemic Inflammatory Response Syndrome; Transcription Factors

To evaluate the clinical value and specificity of atrial natriuretic peptide (ANP) in early diagnosis of sepsis.. A prospective study was performed. Data of patients with sepsis were consecutively collected from September 2007 to December 2012 according to the international criteria for the diagnosis of sepsis, and that of 114 patients admitted to intensive care unit (ICU) and the cadre health care ward were divided into three groups: systemic inflammatory response syndrome (SIRS) group (n=37), sepsis group (n=41) and severe sepsis group (including severe sepsis and septic shock, n=36). Venous blood of each patient was drawn instantly when admitted to ICU. The concentration of plasma ANP in each group was determined on the 1st day using a new type of sandwich immunofluorescence assay, and other biomarkers, such as procalcitonin (PCT, detected with double antibody immunochemi luminometry), blood lactic acid (detected with electrode meter), and C-reactive protein (CRP, detected with immunonephelometric analysis), and the acute physiology and chronic health evaluation II (APACHEII) score was recorded. APACHEII score and biomarkers were compared among three groups. The risk factor for severity was confirmed with stepwise regression, and the value of each index in early diagnosis of sepsis was analyzed with receiver operating characteristic (ROC) curve.. The plasma concentration of ANP exhibited a gradual increase with the aggravation of the disease, and the median ANP value was found to be highest in the severe sepsis group compared with SIRS group and sepsis group [μg/L: 0.26 (0.22) vs. 0.19 (0.05), 0.21 (0.08), P<0.01 and P<0.05]. The regression equation was established at y=0.69 + 0.66APACHEIIscore + 1.285 ANP value, with group as independent variable, and APACHEII score, ANP, PCT, CRP and blood lactic acid value as dependent variables. It could be concluded that APACHEII score and ANP value were correlated with severity of sepsis, and accordingly they were regarded as the independent predictors of severity of sepsis. It was found through the ROC curve analysis of ANP in the sepsis patients, that the area under the ROC curve for ANP [0.805, P=0.000, 95% confidence interval (95%CI) 0.726-0.883, sensitivity 75.8%, specificity 78.4%] was similar with the area under the APACHEII score (0.820, P=0.000, 95%CI 0.742-0.897, sensitivity 68.4%, specificity 78.4%), and it was apparently higher than AUCs of PCT (0.716, P=0.000, 95%CI 0.622-0.810, sensitivity 67.1%, specificity 62.2%), CRP (0.569, P=0.236, 95%CI 0.463-0.675, sensitivity 76.3%, specificity 41.5%), or blood lactic acid (0.566, P=0.254, 95%CI 0.453-0.679, sensitivity 75.0%, specificity 48.6%).. Plasma ANP concentration is clinically valuable in early diagnosis and severity assessment of sepsis, and it is more specific and sensitive than biomarkers PCT and CRP.

Topics: Aged; Aged, 80 and over; Atrial Natriuretic Factor; Early Diagnosis; Female; Humans; Male; Middle Aged; Prospective Studies; Sensitivity and Specificity; Sepsis; Systemic Inflammatory Response Syndrome

Cardioprotective properties of recombinant human Erythropoietin (rhEpo) have been shown in in vivo regional or ex vivo global models of ischemia-reperfusion (I/R) injury. The aim of this study was to characterize the cardioprotective potential of rhEPO in an in vivo experimental model of global I/R approximating the clinical cardiac surgical setting and to gain insights into the myocardial binding sites of rhEpo and the mechanism involved in its cardioprotective effect.. Hearts of donor Lewis rats were arrested with cold crystalloid cardioplegia and after 45 min of cold global ischemia grafted heterotopically into the abdomen of recipient Lewis rats. Recipients were randomly assigned to control non-treated or Epo-treated group receiving 5000 U/kg of rhEpo intravenously 20 min prior to reperfusion. At 5 time points 5-1440 min after reperfusion, the recipients (n=6-8 at each point) were sacrificed, blood and native and grafted hearts harvested for subsequent analysis.. Treatment with rhEpo resulted in a significant reduction in myocardial I/R injury (plasma troponin T) in correlation with preservation of the myocardial redox state (reduced glutathione). The extent of apoptosis (activity of caspase 3 and caspase 9, TUNEL test) in our model was very modest and not significantly affected by rhEpo. Immunostaining of the heart tissue with anti-Epo antibodies showed an exclusive binding of rhEpo to the coronary endothelium with no binding of rhEpo to cardiomyocytes. Administration of rhEpo resulted in a significant increase in nitric oxide (NO) production assessed by plasma nitrite levels. Immunostaining of heart tissue with anti-phospho-eNOS antibodies showed that after binding to the coronary endothelium, rhEpo increased the phosphorylation and thus activation of endothelial nitric oxide synthase (eNOS) in coronary vessels. There was no activation of eNOS in cardiomyocytes.. Intravenous administration of rhEpo protects the heart against cold global I/R. Apoptosis does not seem to play a major role in the process of tissue injury in this model. After binding to the coronary endothelium, rhEpo enhances NO production by phosphorylation and thus activation of eNOS in coronary vessels. Our results suggest that cardioprotective properties of rhEpo are at least partially mediated by NO released by the coronary endothelium.

Topics: Animals; Apoptosis; Atrial Natriuretic Factor; Body Water; Cardiotonic Agents; Coronary Vessels; Disease Models, Animal; Drug Evaluation, Preclinical; Endothelium, Vascular; Erythropoietin; Heart Transplantation; Male; Myocardial Reperfusion Injury; Nitric Oxide; Oxidative Stress; Rats; Rats, Inbred Lew; Recombinant Proteins; Systemic Inflammatory Response Syndrome; Troponin T

Topics: Abdominal Neoplasms; Aorta, Thoracic; Atrial Natriuretic Factor; Biomarkers; Humans; Infusions, Intra-Arterial; Reperfusion Injury; Systemic Inflammatory Response Syndrome

To clarify how plasma atrial natriuretic peptide concentrations vary with the severity of acute lung injury. The influence of coexisting diseases which trigger acute lung injury was also examined.. Prospective study.. Intensive care unit of a university hospital.. Fifty patients who had standard risk factors for acute lung injury including sepsis syndrome, major surgery, prolonged hypotension, aspiration of gastric contents, and burns. Twenty-five of these patients had acute lung injury (group 3) caused by these disorders; the remaining 25 patients had risk factors only (group 2). Ten age-matched normal volunteers were selected as controls (group 1).. None.. Plasma atrial natriuretic peptide concentration was measured in these patients and compared with the severity of acute lung injury. In group 3, a significant increase in the mean plasma atrial natriuretic peptide concentration was observed (188 +/- 78 pg/mL, p < .01) compared with group 2 (54 +/- 28 pg/mL) and the age-matched control group (30 +/- 8 pg/mL). This increase was related to the onset of acute lung injury and returned to control concentrations after recovery. Plasma atrial natriuretic peptide concentrations in group 3 correlated highly with a lung injury score representing the severity of acute lung injury (r2 = .45, p < .01), but did not correlate with other cardiopulmonary variables.. The results suggest that severity of lung injury, but not other predisposing disorders, may be the key factor leading to the increase in plasma atrial natriuretic peptide concentrations observed in these patients.

Topics: Analysis of Variance; Atrial Natriuretic Factor; Burns; Comorbidity; Hemorrhage; Humans; Hypotension; Japan; Linear Models; Pneumonia, Aspiration; Prospective Studies; Respiratory Distress Syndrome; Risk Factors; Systemic Inflammatory Response Syndrome