The GAG-Binding Peptide MIG30 Protects against Liver Ischemia-Reperfusion in Mice.

Ischemia-reperfusion injury (IRI) drives graft rejection and is the main cause of mortality after liver transplantation. During IRI, an intense inflammatory response marked by chemokine production and neutrophil recruitment occurs. However, few strategies are available to restrain this excessive response. Here, we aimed to interfere with chemokine function during IRI in order to disrupt neutrophil recruitment to the injured liver. For this, we utilized a potent glycosaminoglycan (GAG)-binding peptide containing the 30 C-terminal amino acids of CXCL9 (MIG30) that is able to inhibit the binding of chemokines to GAGs in vitro. We observed that mice subjected to IRI and treated with MIG30 presented significantly lower liver injury and dysfunction as compared to vehicle-treated mice. Moreover, the levels of chemokines CXCL1, CXCL2 and CXCL6 and of proinflammatory cytokines TNF-α and IL-6 were significantly reduced in MIG30-treated mice. These events were associated with a marked inhibition of neutrophil recruitment to the liver during IRI. Lastly, we observed that MIG30 is unable to affect leukocytes directly nor to alter the stimulation by either CXCL8 or lipopolysaccharide (LPS), suggesting that its protective properties derive from its ability to inhibit chemokine activity in vivo. We conclude that MIG30 holds promise as a strategy to treat liver IRI and inflammation.

Neutrophils: a cornerstone of liver ischemia and reperfusion injury.

Ischemia-reperfusion injury (IRI) is the main cause of morbidity and mortality due to graft rejection after liver transplantation. During IRI, an intense inflammatory process occurs in the liver. This hepatic inflammation is initiated by the ischemic period but occurs mainly during the reperfusion phase, and is characterized by a large neutrophil recruitment to the liver. Production of cytokines, chemokines, and danger signals results in activation of resident hepatocytes, leukocytes, and Kupffer cells. The role of neutrophils as the main amplifiers of liver injury in IRI has been recognized in many publications. Several studies have shown that elimination of excessive neutrophils or inhibition of their function leads to reduction of liver injury and inflammation. However, the mechanisms involved in neutrophil recruitment during liver IRI are not well known. In addition, the molecules necessary for this type of migration are poorly defined, as the liver presents an atypical sinusoidal vasculature in which the classical leukocyte migration paradigm only partially applies. This review summarizes recent advances in neutrophil-mediated liver damage, and its application to liver IRI. Basic mechanisms of activation of neutrophils and their unique mechanisms of recruitment into the liver vasculature are discussed. In particular, the role of danger signals, adhesion molecules, chemokines, glycosaminoglycans (GAGs), and metalloproteinases is explored. The precise definition of the molecular events that govern the recruitment of neutrophils and their movement into inflamed tissue may offer new therapeutic alternatives for hepatic injury by IRI and other inflammatory diseases of the liver.

Prevalence of Mycoplasma genitalium and Mycoplasma hominis in urogenital tract of Brazilian women.

BACKGROUND: The role of Mycoplasma hominis and M. genitalium in urogenital tract infections remains unknown. Furthermore these mollicutes present a complex relationship with the host immune response. The role of inflammatory cytokines in infections also makes them good candidates to investigate bacterial vaginosis and mycoplasma genital infections. Therefore, the aim of this study was to detect the above-mentioned mollicutes by quantitative Polymerase Chain Reaction (qPCR) methodologies in vaginal swabs and dosage of cytokines. METHODS: Vaginal swabs and peripheral blood were collected from 302 women, including healthy individuals. The molecular findings were correlated with some individual behavioral variables, clinical and demographic characteristics, presence of other important microorganisms in vaginal swabs, and levels of interleukin (IL)-1ß and IL-6. RESULTS: M. hominis and M. genitalium were detected in 31.8% and 28.1% of samples, respectively. The qPCR results were associated with clinical signs and symptoms of the infections studied. The frequency of Trichomonas vaginalis, Gardnerella vaginalis, Neisseria gonorrhoeae and Chlamydia trachomatis was 3.0%, 21.5%, 42.4%, and 1.7% respectively. Increased levels of IL-1ß were associated with the presence of M. hominis and signs and/or symptoms of the genital infection of women studied. CONCLUSION: IL-1ß production was associated with the detection of M. hominis by qPCR. The sexual behavior of women studied was associated with the detection of mycoplasma and other agents of genital infections.

Sepsis induced by Staphylococcus aureus: participation of biomarkers in a murine model.

BACKGROUND: This study aimed to evaluate the role of biomarkers in the pathophysiological process induced by a Staphylococcus aureus strain obtained in a hospital environment. For this, we intraperitoneally inoculated groups of male BALB/c mice with S. aureus, using a clinical isolate (CI) of S. aureus. MATERIAL/METHODS: Mice were divided into groups according to time of euthanasia (24, 48, 72, 96, 120, 144, and 168 hours of infection). After being euthanized, blood samples were collected for quantification of microorganisms and leukocytes, as well as measurement of biomarkers of tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), C-reactive protein (CRP), and Procalcitonin (PCT) by ELISA. Heart, kidneys, and lungs were removed for histopathological analysis, assessment of biomarkers of tissue expression by RT-PCR (polymerase chain reaction with reverse transcriptase), and quantification of microorganisms by real-time quantitative PCR (real-time PCR). RESULTS: The animals infected at between 120 hours and 168 hours had the highest blood levels of S. aureus. We observed that infection promoted increases in the levels of circulating neutrophils and monocytes. However, there was a reduction of circulating neutrophils and monocytes after 96 hours of infection. The infected mice also had increased levels of blood lymphocytes. In this model of infection with S. aureus, IL-6, CRP, and PCT demonstrated greater fidelity as markers of infection, since serum levels were elevated and lowered along with the number of circulating neutrophils and monocytes after resolution of the infection. The lungs showed hyperemia, with enlargement of the alveolar septa. On the other hand, infection with S. aureus did not promote visible change in histological tissue in the heart and kidneys. CONCLUSIONS: In this model of infection with S. aureus, IL-6, CRP, and PCT demonstrated greater fidelity as markers of infection, since serum levels were elevated and lowered along with the number of circulating neutrophils and monocytes after resolution of the infection. We believe our results may provide a better understanding of the pathophysiology, as well as aid in the search for a more reliable method of diagnosis.

Tissue Dependent Role of PTX3 During Ischemia-Reperfusion Injury.

Reperfusion of an ischemic tissue is the treatment of choice for several diseases, including myocardial infarction and stroke. However, reperfusion of an ischemic tissue causes injury, known as Ischemia and Reperfusion Injury (IRI), that limits the benefit of blood flow restoration. IRI also occurs during solid organ transplantation. During IRI, there is activation of the innate immune system, especially neutrophils, which contributes to the degree of injury. It has been shown that PTX3 can regulate multiple aspects of innate immunity and tissue inflammation during sterile injury, as observed during IRI. In humans, levels of PTX3 increase in blood and elevated levels associate with extent of IRI. In mice, there is also enhanced expression of PTX3 in tissues and plasma after IRI. In general, absence of PTX3, as seen in PTX3-deficient mice, results in worse outcome after IRI. On the contrary, increased expression of PTX3, as seen in PTX3 transgenic mice and after PTX3 administration, is associated with better outcome after IRI. The exception is the gut where PTX3 seems to have a clear deleterious role. Here, we discuss mechanisms by which PTX3 contributes to IRI and the potential of taming this system for the treatment of injuries associated with reperfusion of solid organs.

Knowledge and practice of nursing in sickle cell disease and hemoglobinopathies in primary care / Conocimiento y práctica de enfermería en el cuidado de la enfermedad de células falciformes y hemoglobinopatías en la atención primaria / Conhecimento e prática de enfermagem no atendimento à doença falciforme e hemoglobinopatias na atenção primária

ABSTRACT Objective: to investigate the level of knowledge of nurses in Basic Health Units and their engagement in monitoring patients with sickle cell disease and other hemoglobinopathies. Methods: this is a qualitative, descriptive-exploratory study, carried out with 12 nurses from basic health units in the municipality of Santa Luzia/Minas Gerais between August 2018 and February 2019. The semi-structured interview was the technique used for data collection, which was analyzed using Content Analysis. Results: the analysis of the interviews emerged in the construction of three categories: understanding of sickle cell disease, risk factors, and alterations on physical examination; nursing care at the health unit according to the recommendation of the Ministry of Health; obstacles and facilitators for the tracking and identification of patients. Discourse analysis highlighted: the outstanding presence of misconceptions regarding sickle cell disease; the absence of effective follow-up of patients in the area covered by the nurse; and the non-existence of a positive sickle cell disease patient link with primary care. Conclusion: although nursing plays a fundamental role in monitoring and assisting patients with sickle cell disease, the study revealed a significant gap between care recommendations and practice in basic health units.

RESUMEN Objetivo: investigar el nivel de conocimiento de los enfermeros de las Unidades Básicas de Salud y su participación en el seguimiento de pacientes con enfermedad de células falciformes y otras hemoglobinopatías. Método: se trata de un estudio cualitativo descriptivo-exploratorio, realizado con 12 enfermeros de unidades básicas de salud de la ciudad de Santa Luzia/Minas Gerais entre agosto de 2018 y febrero de 2019. La entrevista semiestructurada fue la técnica utilizada para la recolección de datos, que fueron analizados mediante el Análisis de Contenido. Resultados: el análisis de las entrevistas emergió en la construcción de tres categorías: comprensión sobre la enfermedad de células falciformes, factores de riesgo y alteraciones en el examen físico; atención de enfermería en la unidad de salud según recomendación del Ministerio de salud; obstáculos y facilitadores para el seguimiento e identificación de pacientes. El análisis del discurso destacó: la marcada presencia de conceptos erróneos en relación con la enfermedad de células falciformes; la falta de seguimiento efectivo de los pacientes en el área cubierta por la enfermera; y la inexistencia de un vínculo positivo entre el paciente y la enfermedad células falciformes con atención primaria. Conclusiones: si bien la enfermería tiene un papel fundamental en la conducción del seguimiento y atención de los pacientes con enfermedad de células falciformes, el estudio reveló una brecha significativa entre las recomendaciones de atención y la práctica en las unidades básicas de salud.

RESUMO Objetivos: investigar o nível de conhecimento dos enfermeiros das Unidades Básicas de Saúde e o engajamento destes no acompanhamento de pacientes com doença falciforme e outras hemoglobinopatias. Métodos: este é um estudo qualitativo descritivo-exploratório, realizado com 12 enfermeiros de unidades básicas de saúde do município de Santa Luzia/Minas Gerais entre agosto de 2018 a fevereiro de 2019. A entrevista semiestruturada foi a técnica utilizada para coleta de dados, as quais foram analisadas usando a Análise de Conteúdo. Resultados a análise das entrevistas emergiu na construção de três categorias: compreensão sobre a doença falciforme, fatores de risco e alterações ao exame físico; assistência do enfermeiro na unidade de saúde segundo a recomendação do Ministério da Saúde; dificultadores e facilitadores para o rastreamento e identificação dos pacientes. A análise do discurso destacou: a presença marcante de conceitos equivocados em relação à doença falciforme; a ausência de acompanhamento efetivo dos pacientes da área de abrangência do enfermeiro; e a não existência de vínculo entre paciente com doença falciforme positivo e a atenção básica ou uma lacuna significativa entre as recomendações de cuidado e a prática nas unidades básicas de saúde. Conclusão: embora a enfermagem desempenhe um papel fundamental no monitoramento e na assistência aos pacientes com doença falciforme, o estudo revelou uma lacuna significativa entre as recomendações de cuidados e a prática nas unidades básicas de saúde.

Paradoxical Role of Matrix Metalloproteinases in Liver Injury and Regeneration after Sterile Acute Hepatic Failure.

Acetaminophen (APAP) poisoning is one of the leading causes of acute hepatic failure and liver transplantation is often the only lifesaving alternative. During the course of hepatocyte necrosis, an intense accumulation of neutrophils is often observed within the liver microenvironment. Despite the classic idea that neutrophil accumulation in tissues causes collateral tissue damage, there is a growing body of evidence showing that neutrophils can also orchestrate the resolution of inflammation. In this work, drug-induced liver injury was induced by oral administration of APAP and pharmacological intervention was made 12 h after this challenge. Liver injury and repair kinetics were evaluated by a novel combination of enzyme quantifications, ELISA, specific antagonists of neutrophil enzymes and confocal intravital microscopy. We have demonstrated that neutrophil infiltration is not only involved in injury amplification, but also in liver tissue repair after APAP-induced liver injury. In fact, while neutrophil depletion led to reduced hepatic necrosis during APAP poisoning, injury recovery was also delayed in neutropenic mice. The mechanisms underlying the neutrophil reparative role involved rapid degranulation and matrix metalloproteinases (MMPs) activity. Our data highlights the crucial role of neutrophils, in particular for MMPs, in the resolution phase of APAP-induced inflammatory response.

Intravital Microscopic Evaluation of the Effects of a CXCR2 Antagonist in a Model of Liver Ischemia Reperfusion Injury in Mice.

BACKGROUND: Ischemia-reperfusion (IR) is a major contributor to graft rejection after liver transplantation. During IR injury, an intense inflammatory process occurs in the liver. Neutrophils are considered central players in the events that lead to liver injury. CXC chemokines mediate hepatic inflammation following reperfusion. However, few studies have demonstrated in real-time the behavior of recruited neutrophils. We used confocal intravital microscopy (IVM) to image neutrophil migration in the liver and to analyze in real-time parameters of neutrophil recruitment in the inflamed tissue in animals treated or not with reparixin, an allosteric antagonist of CXCR1/2 receptors. MATERIALS AND METHODS: WT and LysM-eGFP mice treated with reparixin or saline were subjected to 60 min of ischemia followed by different times of reperfusion. Mice received Sytox orange intravenously to show necrotic DNA in IVM. The effect of reparixin on parameters of local and systemic reperfusion-induced injury was also investigated. RESULTS: IR induced liver injury and inflammation, as evidenced by high levels of alanine aminotransferase and myeloperoxidase activity, chemokine and cytokine production, and histological outcome. Treatment with reparixin significantly decreased neutrophil influx. Moreover, reparixin effectively suppressed the increase in serum concentrations of TNF-α, IL-6, and CCL3, and the reperfusion-associated tissue damage. The number of neutrophils in the liver increased between 6 and 24 h of reperfusion, whereas the distance traveled, velocity, neutrophil size and shape, and cluster formation reached a maximum 6 h after reperfusion and then decreased gradually. In vivo imaging revealed that reparixin significantly decreased neutrophil infiltration and movement and displacement of recruited cells. Moreover, neutrophils had a smaller size and less elongated shape in treated mice. CONCLUSION: Imaging of the liver by confocal IVM was successfully implemented to describe neutrophil behavior in vivo during liver injury by IR. Treatment with reparixin decreased not only the recruitment of neutrophils in tissues but also their activation state and capacity to migrate within the liver. CXCR1/2 antagonists may be a promising therapy for patients undergoing liver transplantation.

Natriuretic peptide system: a link between fat mass and cardiac hypertrophy and hypertension in fat-fed female rats.

The present study was designed to develop an animal model of hypertension and cardiac hypertrophy associated with obesity in female rats. Furthermore, we studied the involvement of the natriuretic peptide system in the mechanisms of these conditions. Obesity was induced in Wistar rats by a high fat diet and ovariectomy. The rats were divided into four groups: ovariectomized or sham-operated with high-fat diet and ovariectomized or sham-operated with control diet. After 24 weeks of diet, rats were killed, and their tissues were removed. Cardiac atrial natriuretic peptide (ANP), clearance receptor (NPr-C) gene expression was determined by PCR. ANP concentrations were measured in plasma. Ovariectomized fat-fed rats (OF) showed increased body weight, visceral fat depot and blood pressure and decreased sodium excretion compared to other groups. Also, these rats showed higher heart-to-body weight and cell diameters of ventricular cardiomyocytes and lower cardiac ANP mRNA and plasma ANP than the control group. The adipocyte and renal NPr-C mRNA of OF rats were higher than the control group. These data showed that combined ovariectomy and high fat diet elicited obesity, hypertension and cardiac hypertrophy. These results suggest that the impairment of the natriuretic peptide system may be one of the mechanisms involved not only in development of hypertension but also in cardiac hypertrophy associated with obesity in ovariectomized rats.