Mechanism study of OVA-induced allergic asthma in mice based on lipid metabolomics / 中国药理学通报

Aim To investigate the mechanism and search for potential biomarkers of ovalbumin ( OVA ) -induced asthma in mice base on lipidomics. Methods A BALB/c mouse model of asthma was prepared by OVA. TNF-α, IL-4, IL-10, IFN-γ levels in BALF and IgE level in serum were measured by ELISA. The inflammatory changes in mouse lung tissue were observed using HE staining. Lipid mediators ( LMs) in lung tissue and serum were quantified with UPLC-MS/ MS strategy. Results IgE level in serum and TNF-α, IFN-γ levels in BALF were higher (P <0.05) of asthmatic mice.Typical inflammatory manifestations were seen in lung tissue of asthmatic mice. A total of 57 lipid mediators were quantified with UPLC-MRM. LMs metabolic profiles differed significantly in serum and lung tissue between asthmatic and normal mice, 17 significantly different LMs were found in lung tissue and 6 LMs were found in serum, and the differential metabolites were produced through the cyclooxygenase (COX), lipoxygenase (LOX) and cytochrome P450 oxidase (P450) metabolic pathways. Conclusions OVA-induced allergic asthma can cause disorder of lip-id mediators, LMs and cytokines are involved in the occurrence and development of asthma. The differential LMs have potential research value as biomarkers for the development of allergic asthma.

A target lipidomics approach to investigate the acute inflammatory irritation induced by indolealkylamines from Chansu water fraction in rats / 中国天然药物

Chansu has demonstrated adverse reactions in clinical settings, which is associated with its toxicity and limits its clinical applications. But there are methodological limitations for drug safety evaluation. In the current study, ultra-high performance liquid chromatography, lipidomic profiling, and molecular docking were used to systemically assess Chansu-induced acute inflammatory irritation and further identify the underlying drug targets. Compared with the EtOAc extract, Chansu water fraction containing indolealkylamines caused acute inflammatory irritation in rats, including acute pain (spontaneous raising foot reaction), and inflammation (paw edema). At the molecular level, lipids analysis revealed significantly higher levels of pro-inflammatory mediators of the COX and LOX pathways. However, anti-inflammatory mediators from the CYP 450, ALA, and DHA pathways markedly decreased after exposure to Chansu water fraction. Moreover, four indolealkylamines from Chansu showed a high theoretical affinity to a known irritation target, 5-HT

Diverse characters of Brennan’s paw incision model regarding certain parameters in the rat

BACKGROUND: Brennan’s rodent paw incision model has been extensively used for understanding mechanisms underlying postoperative pain in humans. However, alterations of physiological parameters like blood pressure and heart rate, or even feeding and drinking patterns after the incision have not been documented as yet. Moreover, though eicosanoids like prostaglandins and leukotrienes contribute to inflammation, tissue levels of these inflammatory mediators have never been studied. This work further investigates the antinociceptive effect of protein C after intra-wound administration. METHODS: Separate groups of Sprague–Dawley rats were used for quantitation of cyclooxygenase (COX) activity and leukotriene B4 level by enzyme-linked immunosorbent assay, as well as estimation of cardiovascular parameters and feeding and drinking behavior after paw incision. In the next part, rats were subjected to incision and 10 μg of protein C was locally administered by a micropipette. Both evoked and non-evoked pain parameters were then estimated. RESULTS: COX, particularly COX-2 activity and leukotriene B4 levels increased after incision. Hemodynamic parameters were normal. Feeding and drinking were affected on days 1 and 3, and on day 1, respectively. Protein C attenuated non-evoked pain behavior alone up to day 2. CONCLUSIONS: Based upon current observations, Brennan’s rodent paw incision model appears to exhibit a prolonged period of nociception similar to that after surgery, with minimal interference of physiological parameters. Protein C, which is likely converted to activated protein C in the wound, attenuated the guarding score, which probably represents pain at rest after surgery in humans.

Eicosanoids and cancer

Eicosanoids are 20-carbon bioactive lipids derived from the metabolism of polyunsaturated fatty acids, which can modulate various biological processes including cell proliferation, adhesion and migration, angiogenesis, vascular permeability and inflammatory responses. In recent years, studies have shown the importance of eicosanoids in the control of physiological and pathological processes associated with several diseases, including cancer. The polyunsaturated fatty acid predominantly metabolized to generate 2-series eicosanoids is arachidonic acid, which is the major n-6 polyunsaturated fatty acid found in animal fat and in the occidental diet. The three main pathways responsible for metabolizing arachidonic acid and other polyunsaturated fatty acids to generate eicosanoids are the cyclooxygenase, lipoxygenase and P450 epoxygenase pathways. Inflammation plays a decisive role in various stages of tumor development including initiation, promotion, invasion and metastasis. This review will focus on studies that have investigated the role of prostanoids and lipoxygenase-derived eicosanoids in the development and progression of different tumors, highlighting the findings that may provide insights into how these eicosanoids can influence cell proliferation, cell migration and the inflammatory process. A better understanding of the complex role played by eicosanoids in both tumor cells and the tumor microenvironment may provide new markers for diagnostic and prognostic purposes and identify new therapeutic strategies in cancer treatment.

Mast Cells and Lipid Mediators

Human mast cells are potent effector cells in host defense mechanisms of innate and acquired immunity, including inflammatory diseases such as asthma and atherosclerosis. Mast cells originate from pluripotent hematopoietic progenitors in the bone marrow. Activation of mast cells by different stimuli triggers the release of a large range of mediators, including de novo synthesized eicosanoids which are highly biologically active lipid mediators. For the generation of lipid mediators, cytoplasmic lipid droplets have been shown to function as a major intracellular pool of arachidonic acid, the precursor for eicosanoids biosynthesis. The article summarizes current knowledge on mast cell biosynthesis of lipid mediator and the role in inflammation.

Liquid Chromatography-Mass Spectrometry-Based In Vitro Metabolic Profiling Reveals Altered Enzyme Expressions in Eicosanoid Metabolism

BACKGROUND: Eicosanoids are metabolites of arachidonic acid that are rapidly biosynthesized and degraded during inflammation, and their metabolic changes reveal altered enzyme expression following drug treatment. We developed an eicosanoid profiling method and evaluated their changes on drug treatment. METHODS: Simultaneous quantitative profiling of 32 eicosanoids in liver S9 fractions obtained from rabbits with carrageenan-induced inflammation was performed and validated by liquid chromatography-mass spectrometry coupled to anion-exchange solid-phase purification. RESULTS: The limit of quantification for the devised method ranged from 0.5 to 20.0 ng/mg protein, and calibration linearity was achieved (R 2>0.99). The precision (% CV) and accuracy (% bias) ranged from 4.7 to 10.3% and 88.4 to 110.9%, respectively, and overall recoveries ranged from 58.0 to 105.3%. Our method was then applied and showed that epitestosterone treatment reduced the levels of all eicosanoids that were generated by cyclooxygenases and lipoxygenases. CONCLUSIONS: Quantitative eicosanoid profiling combined with in vitro metabolic assays may be useful for evaluating metabolic changes affected by drugs during eicosanoid metabolism.

Eicosanoid Mediators in the Airway Inflammation of Asthmatic Patients: What is New?

Lipid mediators contribute to inflammation providing both pro-inflammatory signals and terminating the inflammatory process by activation of macrophages. Among the most significant biologically lipid mediators, these are produced by free-radical or enzymatic oxygenation of arachidonic acid named "eicosanoids". There were some novel eicosanoids identified within the last decade, and many of them are measurable in clinical samples by affordable chromatography-mass spectrometry equipment or sensitive immunoassays. In this review, we present some recent advances in understanding of the signaling by eicosanoid mediators during asthmatic airway inflammation. Eicosanoid profiling in the exhaled breath condensate, induced sputum, or their metabolites measurements in urine is complementary to the cellular phenotyping of asthmatic inflammation. Special attention is paid to aspirin-exacerbated respiratory disease, a phenotype of asthma manifested by the most profound changes in the profile of eicosanoids produced. A hallmark of this type of asthma with hypersensitivity to non-steroid anti-inflammatory drugs (NSAIDs) is to increase biosynthesis of cysteinyl leukotrienes on the systemic level. It depends on transcellular biosynthesis of leukotriene C₄ by platelets that adhere to granulocytes releasing leukotriene A₄. However, other abnormalities are also reported in this type of asthma as a resistance to anti-inflammatory activity of prostaglandin E₂ or a robust eosinophil interferon-γ response resulting in cysteinyl leukotrienes production. A novel mechanism is also discussed in which an isoprostane structurally related to prostaglandin E₂ is released into exhaled breath condensate during a provoked asthmatic attack. However, it is concluded that any single eicosanoid or even their complex profile can hardly provide a thorough explanation for the mechanism of asthmatic inflammation.

Inflammatory mediators of neuropathic pain / Mediadores inflamatórios na dor neuropática

ABSTRACT BACKGROUND AND OBJECTIVES: Pro-inflammatory chemical mediators and algogenic substances seem to be confused by the sharing of their actions and by interactions in painful and inflammatory presentation. This study aimed at presenting a review of major inflammatory chemical mediators and place them in neuropathic pain pathophysiology. CONTENTS: Inflammation is the homeostatic response of vascularized tissues to remove harmful agents and restore their normal functions. Nervous system (central and/or peripheral) diseases and injuries may induce neuropathic pain and may also modify inflammatory process nervous mediation. In such pathological conditions, there might be pain without restrict link with admitedly harmful or painful stimuli, as well as there might be inflammation without restrict link with the presence of harmful agents and the need to remove them. Chemical mediators involved in neuropathic pain and inflammation pathophysiology modulate the presentation of both. CONCLUSION: Studies on inflammation offer evidences to support the important role of their chemical mediators in neuropathic pain pathogenesis. In peripheral and central sensitization, a thin borderline between reversibility or not of neuropathic pain may be respected or exceeded by inflammatory mediators actions.

RESUMO JUSTIFICATIVA E OBJETIVOS: Mediadores químicos pró-inflamatórios e substâncias algogênicas parecem se confundir pelo compartilhamento de suas ações e pelas interações no quadro doloroso e inflamatório. O objetivo deste estudo foi apresentar uma revisão sobre os principais mediadores químicos inflamatórios e situá-los na fisiopatologia da dor neuropática. CONTEÚDO: A inflamação é a resposta homeostática de tecidos vascularizados no sentido de remoção de agentes lesivos e restauro de suas funções normais. Doenças e lesões no sistema nervoso (central e/ou periférico) podem causar dor neuropática, e, também modificar a mediação nervosa do processo inflamatório. Nessas condições patológicas a dor pode ocorrer sem o vínculo restrito com estímulo reconhecidamente nocivo ou doloroso, assim como ocorrer quadro inflamatório sem o vínculo restrito com a presença de agentes lesivos e a necessidade de removê-los. Os mediadores químicos envolvidos na fisiopatologia da dor neuropática e da inflamação modulam o quadro de ambas. CONCLUSÃO: Os estudos sobre inflamação oferecem evidências para embasar a importância do papel dos seus mediadores químicos na patogênese da dor neuropática. Na sensibilização periférica e, também na central uma fronteira tênue entre a reversibilidade ou não do quadro neuropático pode ser respeitada ou ultrapassada pelas ações de mediadores inflamatórios.

COMPARISON OF SELECTIVE AND NON SELECTIVE CYCLO-OXYGENASE 2 INHIBITORS IN EXPERIMENTAL COLITIS EXACERBATION: role of leukotriene B4 and superoxide dismutase / Comparação dos inibidores seletivos e não seletivos da ciclo-oxigenage 2 na exacerbação da colite experimental: papel do leucotrieno B4 e superóxido dismutase

Context Nonsteroidal anti-inflammatory drugs are considered one of the most important causes of reactivation of inflammatory bowel disease. With regard to selective cyclo-oxygenase 2 inhibitors, the results are controversial in experimental colitis as well as in human studies. Objectives The aim this study is to compare nonsteroidal anti-inflammatory drugs effects, selective and non selective cyclo-oxygenase 2 inhibitors, in experimental colitis and contribute to the understanding of the mechanisms which nonsteroidal anti-inflammatory drugs provoke colitis exacerbation. Methods Six groups of rats: without colitis, with colitis, and colitis treated with celecoxib, ketoprofen, indometacin or diclofenac. Survival rates, hemoglobin, plasmatic albumin, colonic tissue of interleukin-1ß, interleukin-6, tumor necrosis factor alpha, prostaglandin E2, catalase, superoxide dismutase, thiobarbituric acid-reactive substances, chemiluminescence induced by tert-butil hydroperoxides, and tissue and plasmatic leukotriene B4 were determined. Results The groups treated with diclofenac or indometacin presented lower survival rates, hemoglobin and albumin, higher tissue and plasmatic leukotriene B4 and tissue superoxide dismutase than the group treated with celecoxib. Ketoprofen presented an intermediary behavior between diclofenac/indometacin and celecoxib, concerning to survival rate and albumin. The groups without colitis, with colitis and with colitis treated with celecoxib showed leukotriene B4 and superoxide dismutase lower levels than the groups treated with nonselective cyclo-oxygenase 2 inhibitors. Conclusions Diclofenac and indometacin presented the highest degree of induced colitis exacerbation with nonsteroidal anti-inflammatory drugs, celecoxib did not show colitis exacerbation, and ketoprofen presented an intermediary behavior between diclofenac/indometacin and celecoxib. These results suggest that leukotriene B4 and superoxide ...

Contexto Os anti-inflamatórios não-esteróides são considerados uma das mais importantes causas de reativação da doença inflamatória intestinal. Em relação aos inibidores seletivos da ciclo-oxigenase 2, os resultados são controversos tanto em estudos envolvendo humanos como na colite experimental. Objetivos Comparar os efeitos dos anti-inflamatórios não-esteróides, seletivos e não seletivos da ciclo-oxigenase 2, na colite experimental e, contribuir para o entendimento do mecanismo no qual os anti-inflamatórios não-esteróides provocam a exacerbação da colite. Métodos Seis grupos de ratos foram estudados: sem colite, com colite e com colite e tratados com celecoxib, cetoprofeno, indometacina ou diclofenaco. Foram determinadas a taxa de sobrevida, as concentrações de hemoglobina e albumina plasmática, as concentrações teciduais na mucosa colônica de interleucina-1ß, interleucina-6, fator de necrose tumoral alfa, prostaglandina E2, catalase, superóxido dismutase, substâncias reativas ao ácido tiobarbitúrico e quimiluminescência estimulada por hidroperóxido de tert-butil, e as concentraçãos plasmática e tecidual de leucotrieno B4. Resultados O grupo tratado com diclofenaco ou indometacina apresentaram as menores taxas de sobrevida, concentrações de hemoglobina e albumina, e as maiores concentrações plasmática e tecidual de leucotrieno B4 e tecidual de superóxido dismutase do que os groupos tratados com celecoxib. O grupo tratado com cetoprofeno apresentou um comportamento intermediário entre diclofenaco/indometacina e celecoxib, em relação a taxa de sobrevida e albumina. Os grupos sem colite, colite e colite tratado com celecoxib apresentaram menores concentrações de leucotrieno B4 e superóxido ...

Deciphering the contribution of lipid droplets in leprosy: multifunctional organelles with roles in Mycobacterium leprae pathogenesis

Leprosy is an infectious disease caused by Mycobacterium leprae that affects the skin and nerves, presenting a singular clinical picture. Across the leprosy spectrum, lepromatous leprosy (LL) exhibits a classical hallmark: the presence of a collection of M. leprae-infected foamy macrophages/Schwann cells characterised by their high lipid content. The significance of this foamy aspect in mycobacterial infections has garnered renewed attention in leprosy due to the recent observation that the foamy aspect represents cells enriched in lipid droplets (LD) (also known as lipid bodies). Here, we discuss the contemporary view of LD as highly regulated organelles with key functions in M. leprae persistence in the LL end of the spectrum. The modern methods of studying this ancient disease have contributed to recent findings that describe M. leprae-triggered LD biogenesis and recruitment as effective mycobacterial intracellular strategies for acquiring lipids, sheltering and/or dampening the immune response and favouring bacterial survival, likely representing a fundamental aspect of M. leprae pathogenesis. The multifaceted functions attributed to the LD in leprosy may contribute to the development of new strategies for adjunctive anti-leprosy therapies.

Ácidos graxos poli-insaturados n-3 e n-6: metabolismo em mamíferos e resposta imune / Omega-3 and omega-6 polyunsaturated fatty acids: metabolism in mammals and immune response

A experimentação animal apresenta uma grande importância para o desenvolvimento da ciência. O uso de camundongos em experimentos ocorre devido à semelhança destes animais com os seres humanos, fácil criação e manutenção e resposta experimental bastante rápida. Esses animais possuem as mesmas enzimas dessaturases e elongases que os humanos, por isso são usados em pesquisas envolvendo incorporação e síntese de ácidos graxos em tecidos. Os ácidos graxos da família ômega-3 e ômega-6 são de suma importância na dieta humana, pois estes não são sintetizados pela síntese de novo e são precursores dos ácidos graxos poli-insaturados de cadeia muito longa, como os ácidos eicosapentaenóico, docosahexaenóico e araquidônico. Estes desempenham funções importantes no organismo, como a síntese de eicosanóides que estão envolvidos diretamente no sistema imune e nas respostas inflamatórias. A razão entre o consumo de ácidos graxos n-6 e n-3 na dieta é um importante fator para determinar a ingestão adequada de ácidos graxos bem como prevenir o aparecimento de doenças. Este artigo tem como objetivo avaliar a incorporação de ácidos graxos em tecidos de animais e discutir a importância dos ácidos da família n-3 e seus metabólitos no sistema imunológico.

Experiments with animals are very important for the improvement of science. The use of mice in experiments is due to their similarity with humans, the easy of raising and maintaining them and their very fast response. These animals have the same desaturase and elongase enzymes as humans and so they are used in research involving the incorporation and synthesis of fatty acids in tissues. The fatty acids omega-3 and omega-6 are extremely important in the human diet because they are not synthesized de novo and are precursors of very long-chain polyunsaturated fatty acids, such as the eicosapentaenoic, docosahexaenoic and arachidonic acids. These acids play important roles in animals, such as precursors of eicosanoids, which are directly involved in the immune system and inflammatory response. The dietary n-3:n-6 intake ratio is important for assessing proper fatty acid intake and for preventing the development of diseases. Thus, this article assessed the incorporation of fatty acids in animal tissues and discussed the importance of n-3 fatty acids and its metabolites for the immune system.

Prostaglandin E2 Receptors on Upper Respiratory Tract / 대한이비인후과학회지

Prostaglandin (PG) E2 exerts its actions by acting on a group of G-protein-coupled receptors (GPCRs). GPCRs responding to PGE2 consist of four subtypes namely E-prostanoid 1 (EP1), E-prostanoid 2 (EP2), E-prostanoid 3 (EP3), and E-prostanoid 4 (EP4) and multiple splicing isoforms of the subtype EP3. The EP subtypes exhibit differences in signal transduction pathway, tissue localization, and regulation of expression. This molecular and biochemical heterogeneity of PGE2 receptors leads to PGE2 being the most variable prostanoid. Studies on knockout mice deficient in each EP subtype and selective agonist and antagonist have defined PGE2 actions mediated by each subtype and identified the role each EP subtype plays in various physiological and pathophysiological responses. We summarize and review PGE2 receptor research.

Influence of exogenous somatostatin on pancreatic blood flow in normal rats or rats with acute necrotizing pancreatitis / 中国病理生理杂志

AIM: To investigate the influence of exogenous somatostatin (stilamin) on pancreatic blood flow in normal rats or rats with acute necrotizing pancreatitis (ANP).METHODS: Pancreatic blood flow (PBF) was detected with computerized tissue blood flowmeter and rats with ANP were triggered with sodium taurocholate. Metabolites of eicosanoids in plasma were determined with radioimmunoassay. Other laboratory tests including histopathologic observation under optical or electron microscope were used. RESULTS: There was a significant decrease in PBF in normal rats after stilamin administration in comparison with that before use of the drug. There was significant decrease in PBF after onset of ANP, but, compared with that in ANP group, significant increase was shown in SS(stilamin)+ANP group. Plasma thromboxin-B 2(TXB 2) in ANP group at 6 hours after ANP was significantly higher, with increase of 4.5 times, than that in Sham(sham operated) group while TXB 2, detected each time during the course of ANP, significantly decreased in SS+ANP group. 6-Keto-prostagland in F 1? (6-Keto-PGF 1? ) at 6 h after ANP was significantly higher, and the ratio of TXB 2/6-Keto-PGF 1? , significantly lower in SS+ANP group than that in ANP group. Lessened necrosis of acinar cells, along with much fewer microthrombi in microvessels in SS+ANP group, was shown by pathologic scoring or electron microscope than that in ANP group.CONCLUSION: Administration of exogenous somatostatin leads to the decrease in PBF in physiological setting but it attenuates pancreatic ischemia in SS+ANP group, which may be attributed to correction of abnormal metabolism of eicosanoids, improvement of pancreatic microcirculation and cytoprotection of acinar cells as well.

The effects of tetramethylprazine on pancreatic blood flow in acute pancreatitis in rats and its therapy / 中国药理学通报

The effects of tetramethylpy-razine (TMP) on pancreatic blood flow and survival rate were studied in sodium tarocholate-in-duced acute pancreatitis (AP) in rats. The results showed that pancreatic relative blood flow and pancreatic tissue perfusion were significantly increased and the pathologic changes and survival rate were improved in TMP treated group-s. Plasma value of TXB2?6-Keto-PGF1? and platelet aggregation rate (PAR) were also mea-sured. We found that TMP could maintain the balance between TXA2 and PGI2 and lower the elevated PAR. It was suggested that TMP has therapeutic effect on AP in rats through improving pancreatic microcirculation; which was related to the maintanance of the balance between PGI2 and TXA2.