Betaglicerofosfato de Sódio Como Catalisador Negativo na Dosagem dos Fosfatos. Influência da Concentração do Ácido Sulfúrico

Dos trabalhos de Berenblum e Chain (1) sôbre o método de dosagem do fósforo criado por Taylor e Miller, verifica-se que a redução do ácido molíbdico em presença do ácido sulfúrico é acelerada, catalìticamente, pela presença de fósforo sob forma de ânion PO4 Concluíram, também, os mesmos autores a influência da acidez sôbre a decomposição, fixando as melhores condições de reação, isto é, em que a decomposição é mínima na ausência de fósforo e atingindo um máximo quando em presença dêste catalisador após certo tempo. Trabalhando em dosagens de fosfatase alcalina no sôro sangüíneo verificamos que a côr resultante da redução do ácido molíbdico frente a um reativo redutor em presença do fosfato, apresentava algumas alterações que falseavam os resultados. Observamos, também, que o desenvolvimento da côr era mais rápido nos tubos em que se dosava o fósforo livre do sôro, sendo bem mais lento nos tubos em que se media a fosfatase. Relacionamos esse desencontro na estabilização da côr com a presença de betaglicerofosfato de sódio — ou seja - o substrato empregado na avaliação da atividade fosfatásica

Reduced Plasma Nonesterified Fatty Acid Levels and the Advent of an Acute Lung Injury in Mice after Intravenous or Enteral Oleic Acid Administration

Although exerting valuable functions in living organisms, nonesterified fatty acids (NEFAs) can be toxic to cells. Increased blood concentration of oleic acid (OLA) and other fatty acids is detected in many pathological conditions. In sepsis and leptospirosis, high plasma levels of NEFA and low albumin concentrations are correlated to the disease severity. Surprisingly, 24 h after intravenous or intragastric administration of OLA, main NEFA levels (OLA inclusive) were dose dependently decreased. However, lung injury was detected in intravenously treated mice, and highest dose killed all mice. When administered by the enteral route, OLA was not toxic in any tested conditions. Results indicate that OLA has important regulatory properties on fatty acid metabolism, possibly lowering circulating fatty acid through activation of peroxisome proliferator-activated receptors. The significant reduction in blood NEFA levels detected after OLA enteral administration can contribute to the already known health benefits brought about by unsaturated-fatty-acid-enriched diets

Role of Nitric Oxide Synthase in the Function of the Central Nervous System under Normal and Infectious Conditions

Nitric oxide (NO) was discovered as an endothelium‐derived relaxing factor more than two decades ago. Since then, it has been shown to participate in many pathways. NO has been described as a key mediator of different pathways in the central nervous system (CNS) in both healthy and diseased processes. The three isoforms of nitric oxide synthase differ in their activity patterns and expression in different cells. Neuronal nitric oxide synthase (nNOS) is localized in synaptic spines, astrocytes, and the loose connective tissue surrounding blood vessels in the brain; eNOS is present in both cerebral vascular endothelial cells and motor neurons; and iNOS is induced in astrocytes and microglia under pathological conditions. During physiological processes, NO produced by eNOS/nNOS, respectively, controls blood flow activation, and act as a messenger during long‐term potentiation (LTP). However, under pathological conditions, eNOS appears to be impaired, leading to a reduction in blood flow and, consequently, low oxygen/metabolites delivery, efflux of toxicological agents from the brain tissue and disturbance in the blood‐brain barrier. The NO produced by iNOS in glial cells and nNOS, which triggers the NMDA‐excitotoxic pathway, combines with superoxide anion and results in peroxynitrite synthesis, a potent free radical that contributes to tissue damage in the brain. Here, we intend to show the controversial role of the nitric oxide delivered by the three isoforms of the nitric oxide synthase in the CNS, assess its impact under healthy/pathological conditions and speculate on its possible sequela, particularly in long‐term cognitive decline

Development and validation of liquid chromatography-tandem mass spectrometry method to quantify dasatinib in plasma and its application to a pharmacokinetic study

Dasatinib, a potent oral multi-targeted kinase inhibitor against Src and Bcr-Abl, can decrease inflammatory response in sepsis. A simple and cost-effective method for determination of an effective dose dasatinib was established. This method was validated in human plasma, with the aim of reducing the number of animals used, thus, avoiding ethical problems. Dasatinib and internal standard lopinavir were extracted from 180 uL of plasma using liquid-liquid extraction with methyl tert-butil ether, followed by liquid chromatography coupled to triple quadrupole mass spectrometry in multiple reaction monitoring mode. For the pharmacokinetic study, 1 mg/kg of dasatinib was administered to mice with and without sepsis. The method was linear over the concentration range of 1-98 ng/mL for DAS in mice and human plasma, with r2>0.99 and presented intra- and interday precision within the range of 2.3 - 6.2 and 4.3 - 7.0%, respectively. Further intra- and interday accuracy was within the range of 88.2 - 105.8 and 90.6 - 101.7%, respectively. The mice with sepsis showed AUC0-t = 2076.06 h*ng/mL and Cmax =102.73 ng/mL and mice without sepsis presented AUC0-t = 2128.46 h*ng/mL. Cmax = 164.5 ng/mL. The described analytical method was successfully employed in pharmacokinetic study of DAS in mice

Reduced Plasma Nonesterified Fatty Acid Levels and the Advent of an Acute Lung Injury in Mice after Intravenous or Enteral Oleic Acid Administration

Although exerting valuable functions in living organisms, nonesterified fatty acids (NEFAs) can be toxic to cells. Increased blood concentration of oleic acid (OLA) and other fatty acids is detected in many pathological conditions. In sepsis and leptospirosis, high plasma levels of NEFA and low albumin concentrations are correlated to the disease severity. Surprisingly, 24 h after intravenous or intragastric administration of OLA, main NEFA levels (OLA inclusive) were dose dependently decreased. However, lung injury was detected in intravenously treated mice, and highest dose killed all mice. When administered by the enteral route, OLA was not toxic in any tested conditions. Results indicate that OLA has important regulatory properties on fatty acid metabolism, possibly lowering circulating fatty acid through activation of peroxisome proliferator-activated receptors. The significant reduction in blood NEFA levels detected after OLA enteral administration can contribute to the already known health benefits brought about by unsaturatedfatty-acid-enriched diets

Circulating inflammatory mediators and organ dysfunction after cardiovascular surgery with cardiopulmonary bypass: a prospective observational study

INTRODUCTION: Cardiovascular surgery with cardiopulmonary bypass (CPB) has improved in past decades, but inflammatory activation in this setting is still unpredictable and is associated with several postoperative complications. Perioperative levels of macrophage migration inhibitory factor (MIF) and other inflammatory mediators could be implicated in adverse outcomes in cardiac surgery. METHODS: Serum levels of MIF, monocyte chemoattractant protein (MCP)-1, soluble CD40 ligand, IL-6 and IL-10 from 93 patients subjected to CPB were measured by enzyme-linked immunosorbent assay and compared with specific and global postoperative organ dysfunctions through multiple organ dysfunction score (MODS) and sequential organ failure assessment (SOFA). RESULTS: Most of the cytokines measured had a peak of production between 3 and 6 hours after CPB, but maximum levels of MIF occurred earlier, at the cessation of CPB. Among specific organ dysfunctions, the most frequent was hematological, occurring in 82% of the patients. Circulatory impairment was observed in 73.1% of the patients, and 51% of these needed inotropics or vasopressors within the first 24 hours after surgery. The third most frequent dysfunction was pulmonary, occurring in 48.4% of the patients. Preoperative levels of MIF showed a relevant direct correlation with the intensity of global organ dysfunction measured by SOFA (ρ = 0.46, p < 0.001) and MODS (ρ = 0.50, p < 0.001) on the third day after surgery. MCP-1 production was associated with postoperative thrombocytopenia, and MIF was related to the use of a high dose of vasopressors in patients with cardiovascular impairment and also to lower values of the ratio of partial arterial oxygen tension (PaO(2)) to fraction of inspired oxygen (FiO(2)) registered in the first 24 hours after CPB. CONCLUSION: Despite the multifactorial nature of specific or multiple organ dysfunctions, MIF should be explored as a predicting factor of organ dysfunction, or even as a potential therapeutic target in decreasing postoperative complications

Gestational sepsis and the possible breakdown of the placental blood barrier and fetal bacterial infection: A literature review / Sepse em período gestacional e a possível quebra da barreira hemato placentária e infecção bacteriana fetal: Revisão de literatura

Objetivo: Realizar uma revisão de literatura sobre particularidades da sepse na gestação e sua intrínseca relação com a quebra da barreira hemato-placentária, gerando comprometimento cognitivo, sináptico e inflamatório no feto ao decorrer de sua vida.  Métodos: Foi realizada uma revisão integrativa de literatura consultando artigos científicos clínicos e experimentais indexados nas bases eletrônicas LILACS, SCIELO e MEDLINE, a partir do ano 2000, obedecendo etapas metodológicas para analisar a relação entre sepse gestacional e depleção da barreira hemato-placentária. Resultados: A sepse na gestação induz a quebra da barreira hemato-placentária e uma resposta pró-inflamatória sistêmica, havendo comprometimento no desenvolvimento do SNC fetal. Adaptações fisiológicas maternas que ocorrem no estado gravídico resultam em um diagnóstico dificultoso e tardio, acarretando uma resposta inflamatória progressivamente exacerbada do organismo materno e gerando danos severos na barreira hematoplacentária e no neurodesenvolvimento do feto. Ainda não há um mecanismo claro definido pelo qual a injúria à barreira ocorre, porém, alguns fatores formadores dessa estrutura protetora possuem forte relação fisiopatológica com o quadro. Contudo, estudos experimentais em camundongos sugerem uma elevada resposta inflamatória em regiões específicas do SNC, principalmente na região hipocampal, no lobo frontal do córtex e no cerebelo, juntamente com a diminuição de sinaptofisina nesses locais, e demonstraram comprometimento na memória, dificuldade de aprendizagem e uma forte relação com quadros depressivos nos camundongos neonatos, indicando que a sepse também é atrelada à distúrbios neurológicos.   Conclusão: É necessário alertar sobre as particularidades fisiológicas e bioquímicas acerca da doença inflamatória e seu comprometimento, principalmente fetal. Atrasos na identificação e no tratamento da Sepse na gestação são importantes no prognóstico e passíveis de intervenção. A depleção da barreira hemato-placentária leva a alterações no neurodesenvolvimento e podem estar ligadas à danos sinápticos, sugerindo que o quadro clínico é um fator de risco negligenciado para depressão, aprendizagem e problemas de memória na infância e na vida adulta.

The Na/K-ATPase role as a signal transducer in lung inflammation

Acute respiratory distress syndrome (ARDS) is marked by damage to the capillary endothelium and alveolar epithelium following edema formation and cell infiltration. Currently, there are no effective treatments for severe ARDS. Pathologies such as sepsis, pneumonia, fat embolism, and severe trauma may cause ARDS with respiratory failure. The primary mechanism of edema clearance is the epithelial cells’ Na/K-ATPase (NKA) activity. NKA is an enzyme that maintains the electrochemical gradient and cell homeostasis by transporting Na+ and K+ ions across the cell membrane. Direct injury on alveolar cells or changes in ion transport caused by infections decreases the NKA activity, loosening tight junctions in epithelial cells and causing edema formation. In addition, NKA acts as a receptor triggering signal transduction in response to the binding of cardiac glycosides. The ouabain (a cardiac glycoside) and oleic acid induce lung injury by targeting NKA. Besides enzymatic inhibition, the NKA triggers intracellular signal transduction, fostering proinflammatory cytokines production and contributing to lung injury. Herein, we reviewed and discussed the crucial role of NKA in edema clearance, lung injury, and intracellular signaling pathway activation leading to lung inflammation, thus putting the NKA as a protagonist in lung injury pathology

Omega-9 Oleic Acid, the Main Compound of Olive Oil, Mitigates Inflammation during Experimental Sepsis

The Mediterranean diet, rich in olive oil, is beneficial, reducing the risk of cardiovascular diseases and cancer. Olive oil is mostly composed of the monounsaturated fatty acid omega-9. We showed omega-9 protects septic mice modulating lipid metabolism. Sepsis is initiated by the host response to infection with organ damage, increased plasma free fatty acids, high levels of cortisol, massive cytokine production, leukocyte activation, and endothelial dysfunction. We aimed to analyze the effect of omega-9 supplementation on corticosteroid unbalance, inflammation, bacterial elimination, and peroxisome proliferator-activated receptor (PPAR) gamma expression, an omega-9 receptor and inflammatory modulator. We treated mice for 14 days with omega-9 and induced sepsis by cecal ligation and puncture (CLP). We measured systemic corticosterone levels, cytokine production, leukocyte and bacterial counts in the peritoneum, and the expression of PPAR gamma in both liver and adipose tissues during experimental sepsis. We further studied omega-9 effects on leukocyte rolling in mouse cremaster muscle-inflamed postcapillary venules and in the cerebral microcirculation of septic mice. Here, we demonstrate that omega-9 treatment is associated with increased levels of the anti-inflammatory cytokine IL-10 and decreased levels of the proinflammatory cytokines TNF-alpha and IL-1 beta in peritoneal lavage fluid of mice with sepsis. Omega-9 treatment also decreased systemic corticosterone levels. Neutrophil migration from circulation to the peritoneal cavity and leukocyte rolling on the endothelium were decreased by omega-9 treatment. Omega-9 also decreased bacterial load in the peritoneal lavage and restored liver and adipose tissue PPAR gamma expression in septic animals. Our data suggest a beneficial anti-inflammatory role of omega-9 in sepsis, mitigating leukocyte rolling and leukocyte influx, balancing cytokine production, and controlling bacterial growth possibly through a PPAR gamma expression-dependent mechanism. The significant reduction of inflammation detected after omega-9 enteral injection can further contribute to the already known beneficial properties facilitated by unsaturated fatty acid-enriched diets