Measurement of multiple cytokines for discrimination and risk stratification in patients with Chagas' disease and idiopathic dilated cardiomyopathy.

Chagas' disease (CD), caused by the hemoflagellate protozoan, Trypanosoma cruzi, is endemic in most countries of Latin America. Heart failure (HF) is often a late manifestation of chronic CD, and is associated with high morbidity and mortality. Inflammatory processes mediated by cytokines play a key role in the pathogenesis and progression of CD. Keeping in view the inflammatory nature of CD, this study investigated the possible role of 21 different inflammatory cytokines as biomarkers for prediction and prognosis of CD. The plasma concentration of these cytokines was measured in a group of patients with CD (n = 94), and then compared with those measured in patients with dilated cardiomyopathy (DCM) from idiopathic causes (n = 48), and with control subjects (n = 25). Monovariately, plasma levels of cytokines such as stem cell growth factor beta (SCGF beta), hepatocyte growth factor (HGF), monokine induced by interferon gamma (CXCL9), and macrophage inhibitory factor (MIF) were significantly increased in CD patients with advanced HF compared to control group. None of the cytokines could demonstrate any prognostic potency in CD patients, and only MIF and stromal derived factor-1 alpha (CXCL12) showed significance in predicting mortality and necessity for heart transplant in DCM patients. However, multivariate analysis prognosticated a large proportion of CD and DCM patients. In CD patients, HGF and Interleukin-12p40 (IL-12p40) together separated 81.9% of 3-year survivors from the deceased, while in DCM patients, CXCL12, stem cell factor (SCF), and CXCL9 together discriminated 77.1% of survivors from the deceased. The significant increase in plasma concentrations of cytokines such as HGF and CXCL9 in CD patients, and the ability of these cytokines to prognosticate a large proportion of CD and DCM patients multivariately, encourages further studies to clarify the diagnostic and prognostic potential of cytokines in such patients.

Oestrogen-mediated upregulation of the Mas receptor contributes to sex differences in acute lung injury and lung vascular barrier regulation.

Epidemiological data from the SARS-CoV-2 outbreak suggest sex differences in mortality and vulnerability; however, sex-dependent incidence of acute respiratory distress syndrome (ARDS) remains controversial and the sex-dependent mechanisms of endothelial barrier regulation are unknown. In premenopausal women, increased signalling of angiotensin (Ang)(1-7) via the Mas receptor has been linked to lower cardiovascular risk. Since stimulation of the Ang(1-7)/Mas axis protects the endothelial barrier in acute lung injury (ALI), we hypothesised that increased Ang(1-7)/Mas signalling may protect females over males in ALI/ARDS.Clinical data were collected from Charité inpatients (Berlin) and sex differences in ALI were assessed in wild-type (WT) and Mas-receptor deficient (Mas-/- ) mice. Endothelial permeability was assessed as weight change in isolated lungs and as transendothelial electrical resistance (TEER) in vitroIn 734 090 Charité inpatients (2005-2016), ARDS had a higher incidence in men as compared to women. In murine ALI, male WT mice had more lung oedema, protein leaks and histological evidence of injury than female WT mice. Lung weight change in response to platelet-activating factor (PAF) was more pronounced in male WT and female Mas-/- mice than in female WT mice, whereas Mas-receptor expression was higher in female WT lungs. Ovariectomy attenuated protection in female WT mice and reduced Mas-receptor expression. Oestrogen increased Mas-receptor expression and attenuated endothelial leakage in response to thrombin in vitro This effect was alleviated by Mas-receptor blockade.Improved lung endothelial barrier function protects female mice from ALI-induced lung oedema. This effect is partially mediated via enhanced Ang(1-7)/Mas signalling as a result of oestrogen-dependent Mas expression.

Age-dependent differences in pulmonary host responses in ARDS: a prospective observational cohort study.

BACKGROUND: Results from preclinical studies suggest that age-dependent differences in host defense and the pulmonary renin-angiotensin system (RAS) are responsible for observed differences in epidemiology of acute respiratory distress syndrome (ARDS) between children and adults. The present study compares biomarkers of host defense and RAS in bronchoalveolar lavage (BAL) fluid from neonates, children, adults, and older adults with ARDS. METHODS: In this prospective observational study, we enrolled mechanical ventilated ARDS patients categorized into four age groups: 20 neonates (< 28 days corrected postnatal age), 29 children (28 days-18 years), 26 adults (18-65 years), and 17 older adults (> 65 years of age). All patients underwent a nondirected BAL within 72 h after intubation. Activities of the two main enzymes of RAS, angiotensin converting enzyme (ACE) and ACE2, and levels of biomarkers of inflammation, endothelial activation, and epithelial damage were determined in BAL fluid. RESULTS: Levels of myeloperoxidase, interleukin (IL)-6, IL-10, and p-selectin were higher with increasing age, whereas intercellular adhesion molecule-1 was higher in neonates. No differences in activity of ACE and ACE2 were seen between the four age groups. CONCLUSIONS: Age-dependent differences in the levels of biomarkers in lungs of ARDS patients are present. Especially, higher levels of markers involved in the neutrophil response were found with increasing age. In contrast to preclinical studies, age is not associated with changes in the pulmonary RAS.

Further intracellular proteins and signaling pathways regulated by angiotensin-(1-7) in human endothelial cells.

In 2016, Meinert et al. (doi: 10.1016/j.jprot.2015.09.020) published the first 25 proteins in a protein array regulated in Human Umbilical Vein Endothelial Cells (HUVEC) by the heptapeptide angiotensin (Ang)-(1-7) and the first 10 intracellular signaling cascades at different time points. This supporting data article shows further proteins and pathways stimulated by Ang-(1-7) in human endothelial cells at time points of 1 h, 3 h, 6 h, and 9 h. HUVECs were stimulated with Ang-(1-7), and regulated proteins were identified via antibody microarray. Bioinformatics software IPA was used for association of regulated proteins to metabolic pathways.

Therapeutic time window for angiotensin-(1-7) in acute lung injury.

BACKGROUND AND PURPOSE: There is presently no proven pharmacological therapy for the acute respiratory distress syndrome. Recently, we and others discovered that the heptapeptide angiotensin-(1-7) [Ang-(1-7)] shows significant beneficial effects in preclinical models of acute lung injury (ALI). Here, we aimed to identify the best time window for Ang-(1-7) administration to protect rats from oleic acid (OA) induced ALI. EXPERIMENTAL APPROACH: The effects of i.v. infused Ang-(1-7) were examined over four different time windows before or after induction of ALI in male Sprague-Dawley rats. Haemodynamic effects were continuously monitored, and loss of barrier function, inflammation and lung peptidase activities were measured as experimental endpoints. KEY RESULTS: Ang-(1-7) infusion provided the best protection against experimental ALI when administered by continuous infusion starting immediately after 30 min OA infusion till the end of the experiment (30-240 min). Both pretreatment (-60 to 0 min before OA) and short-term therapy (30-90 min) also had beneficial effects although less pronounced than the effects achieved with the optimal therapy window. Starting infusion of Ang-(1-7) 60 min after the end of OA treatment (90-240 min) did not protect barrier function or haemodynamics but still reduced myeloperoxidase activity and increased ACE2/ACE activity ratio respectively. CONCLUSIONS AND IMPLICATIONS: Our findings indicate that early initiation of therapy after ALI and continuous drug delivery are most beneficial for optimal therapeutic efficiency of Ang-(1-7) treatment in experimental ALI and, presumably accordingly, in clinical acute respiratory distress syndrome.

Styrene induces an inflammatory response in human lung epithelial cells via oxidative stress and NF-kappaB activation.

Styrene is a volatile organic compound (VOC) that is widely used as a solvent in many industrial settings. Chronic exposure to styrene can result in irritation of the mucosa of the upper respiratory tract. Contact of styrene with epithelial cells stimulates the expression of a variety of inflammatory mediators, including the chemotactic cytokine monocyte chemoattractant protein-1 (MCP-1). To characterise the underlying mechanisms of the induction of inflammatory signals by styrene, we investigated the influence of this compound on the induction of oxidative stress and the activation of the nuclear factor-kappa B (NF-kappaB) signalling pathway in human lung epithelial cells (A549). The results demonstrate that styrene-induced MCP-1 expression, as well as the expression of the oxidative stress marker glutathione S-transferase (GST), is associated with a concentration dependent pattern of NF-kappaB activity. An inhibitor of NF-kappaB, IKK-NBD, and the anti-inflammatory antioxidant N-acetylcysteine (NAC) were both effective in suppressing styrene-induced MCP-1 secretion. In addition, NAC was capable of inhibiting the upregulation of GST expression. Our findings suggest that the activation of the NF-kappaB signalling pathway by styrene is mediated via a redox-sensitive mechanism.