The Role of Kinin Receptors in Preventing Neuroinflammation and Its Clinical Severity during Experimental Autoimmune Encephalomyelitis in Mice

Background: Multiple sclerosis (MS) is a demyelinating and neuroinflammatory disease of the human central nervous system (CNS). the expression of kinins is increased in MS patients, but the underlying mechanisms by which the kinin receptor regulates MS development have not been elucidated.Methodology/Principal Findings: Experimental autoimmune encephalomyelitis (EAE) was induced in female C57BL/6 mice by immunization with MOG(35-55) peptide emulsified in complete Freund's adjuvant and injected with pertussis toxin on day 0 and day 2. Here, we report that blockade of the B(1)R in the induction phase of EAE markedly suppressed its progression by interfering with the onset of the immune response. Furthermore, B(1)R antagonist suppressed the production/expression of antigen-specific T(H)1 and T(H)17 cytokines and transcription factors, both in the periphery and in the CNS. in the chronic phase of EAE, the blockade of B(1)R consistently impaired the clinical progression of EAE. Conversely, administration of the B(1)R agonist in the acute phase of EAE suppressed disease progression and inhibited the increase in permeability of the blood-brain barrier (BBB) and any further CNS inflammation. of note, blockade of the B(2)R only showed a moderate impact on all of the studied parameters of EAE progression.Conclusions/Significance: Our results strongly suggest that kinin receptors, mainly the B(1)R subtype, play a dual role in EAE progression depending on the phase of treatment through the lymphocytes and glial cell-dependent pathways.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Programa de Apoio aos Nucleos de Excelencia (PRONEX), BrazilFundacaode Apoio a Pesquisa Cientifica Tecnologica do Estado de Santa Catarina (FAPESC), BrazilUniv Fed Santa Catarina, Dept Pharmacol, Ctr Biol Sci, Florianopolis, SC, BrazilUniversidade Federal de São Paulo, Dept Biophys, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biophys, São Paulo, BrazilWeb of Scienc

Chronic Overexpression of Bradykinin in Kidney Causes Polyuria and Cardiac Hypertrophy

Acute intra-renal infusion of bradykinin increases diuresis and natriuresis via inhibition of vasopressin activity. However, the consequences of chronically increased bradykinin in the kidneys have not yet been studied. A new transgenic animal model producing an excess of bradykinin by proximal tubular cells (KapBK rats) was generated and submitted to different salt containing diets to analyze changes in blood pressure and other cardiovascular parameters, urine excretion, and composition, as well as levels and expression of renin-angiotensin system components. Despite that KapBK rats excrete more urine and sodium, they have similar blood pressure as controls with the exception of a small increase in systolic blood pressure (SBP). However, they present decreased renal artery blood flow, increased intrarenal expression of angiotensinogen, and decreased mRNA expression of vasopressin V1A receptor (AVPR1A), suggesting a mechanism for the previously described reduction of renal vasopressin sensitivity by bradykinin. Additionally, reduced heart rate variability (HRV), increased cardiac output and frequency, and the development of cardiac hypertrophy are the main chronic effects observed in the cardiovascular system. In conclusion: (1) the transgenic KapBK rat is a useful model for studying chronic effects of bradykinin in kidney; (2) increased renal bradykinin causes changes in renin angiotensin system regulation; (3) decreased renal vasopressin sensitivity in KapBK rats is related to decreased V1A receptor expression; (4) although increased renal levels of bradykinin causes no changes in mean arterial pressure (MAP), it causes reduction in HRV, augmentation in cardiac frequency and output and consequently cardiac hypertrophy in rats after 6 months of age

Atherosclerosis severity in patients with familial hypercholesterolemia: the role of T and B lymphocytes

Background and aims Familial hypercholesterolemia (FH) is characterized by lifelong exposure to high LDL-c concentrations and premature atherosclerotic cardiovascular disease; nevertheless, disease severity can be heterogeneous. We aimed at evaluating if the immune-inflammatory system could modulate atherosclerosis burden in FH. Methods From a cohort of subjects with confirmed FH (Dutch Lipid Clinic Network and genotype), 92 patients receiving high-intensity lipid-lowering therapy (statin ± ezetimibe) were included. The extension and severity of coronary atherosclerosis was assessed by standardized reporting systems (CAD-RADS) for coronary computed tomography angiography (CCTA) and coronary artery calcium (CAC) scores. Lipids, apolipoproteins, anti-oxLDL and anti-apolipoprotein B-D peptide (anti-ApoB-D) autoantibodies (IgM and IgG), lymphocytes subtypes, platelet, monocyte and endothelial microparticles (MP), IgM levels (circulating or produced by B1 cells) and cytokines in the supernatant of cultured cells were determined. Multiple linear regression models evaluated associations of these biomarkers with CAC and CAD-RADS scores. Results In univariate analysis CAC correlated with age, systolic blood pressure, TCD4+ cells, and titers of IgM anti-ApoB-D. In multiple linear regression [ANOVA F = 2.976; p = 0.024; R2 = 0.082), CD4+T lymphocytes (B = 35.289; beta = 0.277; p = 0.010; 95%CI for B 8.727 to 61.851), was independently associated with CAC. CAD-RADS correlated with age, systolic blood pressure, titers of IgM anti-ApoB-D, and endothelial MP in univariate analysis. In multiple linear regression, [ANOVA F = 2.790; p = 0.032; R2 = 0.119), only age (B = 0.027; beta = 0.234; p = 0.049; 95% CI for B 0.000 to 0.053) was independent predictor. Conclusions In subjects with FH, under high-intensity lipid-lowering therapy, age and CD4+T cells were associated to atherosclerosis burden

A rare mutation in the F12 gene in a patient with ACE inhibitor-induced angioedema

Sao Paulo Research Foundation-FAPESPUniv Fed Sao Paulo, Dept Biophys, Sao Paulo, SP, BrazilEscola Super Ciencias Santa Casa Misericor Vitoria, Sch Med, Vitoria, ES, BrazilUniv Fed Sao Paulo, Dept Biophys, Sao Paulo, SP, BrazilFAPESP: 2011/24142-3FAPESP: 2013/02661-4Web of Scienc

RNA and DNA aptamers in cytomics analysis

Background: the systematic evolution of ligands by exponential enrichment (SELEX) technique is a combinatorial library approach in which DNA or RNA molecules (aptamers) are selected by their ability to bind their protein targets with high affinity and specificity, comparable to that of monoclonal antibodies. in contrast to antibodies conventionally selected in animals, aptamers are generated by an in vitro selection process, and can be directed against almost every target, including antigens like toxins or nonimmunogenic targets, against which conventional antibodies cannot be raised.Methods: Aptamers are ideal candidates for cytomics, as they can be attached to fluorescent reporters or nanoparticles in order to study biological function by fluorescence microscopy, by flow cytometry, or to quantify the concentration of their target in biological fluids or cells using ELISA, RIA, and Western blot assays.Results: We demonstrate the in vitro selection of antikinin B1 receptor aptamers that could be used to determine B1 receptor expression during inflammation processes. These aptamers specifically recognize their target in a Northern-Western blot assay, and bind to their target protein whenever they are exposed in the membrane.Conclusions: Currently, aptamers are linked to fluorescent reporters. We discuss here the present status and future directions concerning the use of the SELEX technique in cytomics. (C) 2004 Wiley-Liss, Inc

Reduced nerve injury-induced neuropathic pain in kinin B-1 receptor knock-out mice

Injury to peripheral nerves often results in a persistent neuropathic pain condition that is characterized by spontaneous pain, allodynia, and hyperalgesia. Nerve injury is accompanied by a local inflammatory reaction in which nerve-associated and immune cells release several pronociceptive mediators. Kinin B-1 receptors are rarely expressed in nontraumatized tissues, but they can be expressed after tissue injury. Because B-1 receptors mediate chronic inflammatory painful processes, we studied their participation in neuropathic pain using receptor gene-deleted mice. in the absence of neuropathy, we found no difference in the paw-withdrawal responses to thermal or mechanical stimulation between B-1 receptor knock-out mice and 129/J wild-type mice. Partial ligation of the sciatic nerve in the wild-type mouse produced a profound and long-lasting decrease in thermal and mechanical thresholds in the paw ipsilateral to nerve lesion. Threshold changed neither in the sham-operated animals nor in the paw contralateral to lesion. Ablation of the gene for the B-1 receptor resulted in a significant reduction in early stages of mechanical allodynia and thermal hyperalgesia. Furthermore, systemic treatment with the B-1 selective receptor antagonist des-Arg(9)-[Leu(8)]-bradykinin reduced the established mechanical allodynia observed 7-28d after nerve lesion in wild-type mice. Partial sciatic nerve ligation induced an upregulation in B-1 receptor mRNA in ipsilateral paw, sciatic nerve, and spinal cord of wild-type mice. Together, kinin B-1 receptor activation seems to be essential to neuropathic pain development, suggesting that an oral-selective B-1 receptor antagonist might have therapeutic potential in the management of chronic pain.Univ Fed Santa Catarina, Dept Pharmacol, Ctr Biol Sci, BR-88049900 Florianopolis, SC, BrazilEscola Paulista Med, Dept Biophys, BR-04023062 São Paulo, BrazilUniv Mogi Cruzes, BR-0878091 Mogi Das Cruzes, BrazilMax Delbruck Ctr Mol Med, D-13125 Berlin, GermanyEscola Paulista Med, Dept Biophys, BR-04023062 São Paulo, BrazilWeb of Scienc

Computation of genus and braid index for renormalizable Lorenz links

We present and analyse two new algorithms to compute some combinatorial in- variants, the genus and the braid index, of renormalizable Lorenz links. We im- plement them, evaluate their complexities and compare it with the classical ones, confirming a drastic reduction of complexity