RESUMO
Seaweed lectins are very promising biotechnological tools that also gain prominence when applied to the pharmacology field. The purpose of the present work was to isolate and characterize lectin from the red algae Amansia multifida and subsequently test it in general inflammation models. The lectin was purified by ion exchange chromatography, characterized with two-dimensional electrophoresis, automated analysis of amino acid sequences and circular dichroism spectroscopy. The pharmacological tests performed were paw edema induced by carrageenan or rapid inflammatory mediators, peritonitis induced by carrageenan and myeloperoxidase leukocyte count assays, glutathione and cytokine concentration. Our results have identified a 30 KDa molecular weight protein that presents a major secondary structure arranged in ß-strand elements (~43%). A fragment of 20 amino acid residues was sequenced and presented low identity to the known classes of lectins from marine alga. This lectin was able to modulate inflammatory parameters such as paw edema, leukocyte migration, oxidative stress and proinflammatory cytokines. Thus, the lectin from the seaweed Amansia multifida has evident anti-inflammatory properties because it acts by reducing the formation of edema by modulating the effect of vascular mediators, migration of neutrophils, proinflammatory cytokines and oxidative stress control.
Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Lectinas/química , Lectinas/farmacologia , Rodófitas/química , Animais , Carragenina/farmacologia , Movimento Celular/efeitos dos fármacos , Citocinas/metabolismo , Edema/tratamento farmacológico , Edema/metabolismo , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Mediadores da Inflamação/química , Mediadores da Inflamação/farmacologia , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Camundongos , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Peritonite/tratamento farmacológico , Peritonite/metabolismo , Peroxidase/metabolismoRESUMO
Adipose tissue secretes proinflammatory mediators which promote systemic and adipose tissue inflammation seen in obesity. Group IIA (GIIA)-secreted phospholipase A2 (sPLA2) enzymes are found to be elevated in plasma and adipose tissue from obese patients and are active during inflammation, generating proinflammatory mediators, including prostaglandin E2 (PGE2). PGE2 exerts anti-lipolytic actions and increases triacylglycerol levels in adipose tissue. However, the inflammatory actions of GIIA sPLA2s in adipose tissue cells and mechanisms leading to increased PGE2 levels in these cells are unclear. This study investigates the ability of a representative GIIA sPLA2, MT-III, to activate proinflammatory responses in preadipocytes, focusing on the biosynthesis of prostaglandins, adipocytokines and mechanisms involved in these effects. Our results showed that MT-III induced biosynthesis of PGE2, PGI2, MCP-1, IL-6 and gene expression of leptin and adiponectin in preadipocytes. The MT-III-induced PGE2 biosynthesis was dependent on cytosolic PLA2 (cPLA2)-α, cyclooxygenases (COX)-1 and COX-2 pathways and regulated by a positive loop via the EP4 receptor. Moreover, MT-III upregulated COX-2 and microsomal prostaglandin synthase (mPGES)-1 protein expression. MCP-1 biosynthesis induced by MT-III was dependent on the EP4 receptor, while IL-6 biosynthesis was dependent on EP3 receptor engagement by PGE2. These data highlight preadipocytes as targets for GIIA sPLA2s and provide insight into the roles played by this group of sPLA2s in obesity.
Assuntos
Tecido Adiposo/metabolismo , Mediadores da Inflamação/metabolismo , Obesidade/metabolismo , Fosfolipases A2/metabolismo , Células 3T3-L1 , Animais , Células Cultivadas , Mediadores da Inflamação/química , CamundongosRESUMO
Lectins are a widely studied group of proteins capable of specific and reversible binding to carbohydrates. Undoubtedly, the best characterized are those extracted from plants of the Leguminosae family. Inside this group of proteins, those from the Diocleinae subtribe have attracted attention, in particular Concanavalin A (ConA), the best-studied lectin of the group. Diocleinae lectins, also called ConA-like lectins, present a high similarity of sequence and three-dimensional structure and are known to present inflammatory, vasoactive, antibiotic, immunomodulatory and antitumor activities, among others. This high similarity of lectins inside the ConA-like group makes it possible to use them to study structure/biological activity relationships by the variability of both carbohydrate specificity and biological activities results. It is in this context the following review aims to summarize the most recent data on the biochemical and structural properties, as well as biological activities, of ConA-like lectins and the use of these lectins as models to study structure/biological activity relationships.
Assuntos
Concanavalina A/química , Concanavalina A/farmacologia , Lectinas/química , Lectinas/farmacologia , Carboidratos/química , Fenômenos Químicos , Concanavalina A/genética , Concanavalina A/isolamento & purificação , Mediadores da Inflamação/química , Mediadores da Inflamação/metabolismo , Mediadores da Inflamação/farmacologia , Lectinas/genética , Lectinas/isolamento & purificação , Relação Estrutura-AtividadeRESUMO
DwL, a lectin extracted from the seeds of Dioclea wilsonii, is a metalloprotein with strong agglutinating activity against rabbit and ABO erythrocytes, inhibited by glucose and mannose. DwL was purified by affinity chromatography on a Sephadex G-50 column and ion exchange chromatography on a HiTrap SP XL column. SDS-PAGE revealed three electrophoretic bands corresponding to the α (25,634 ± 2 Da), ß (12,873 ± 2 Da) and γ (12,779 ± 2 Da) chains. Protein sequencing was done by Tandem Mass Spectrometry. The primary sequence featured 237 amino acids and was highly homologous to other reported Diocleinae lectins. A complete X-ray dataset was collected at 2.0 Å for X-Man-complexed DWL crystals produced by the vapor diffusion method. The crystals were orthorhombic and belonged to the space group I222, with the unit-cell parameters a = 59.6, b = 67.9 and c = 109.0 Å. DWL differed in potency from other ConA-like lectins and was found to induce neutrophil migration in rats, making it particularly useful in structural/functional studies of this class of proteins.
Assuntos
Dioclea/química , Mediadores da Inflamação/química , Lectinas de Plantas/química , Sementes/química , Sequência de Aminoácidos , Animais , Movimento Celular/efeitos dos fármacos , Sequência Conservada , Cristalização , Eritrócitos/efeitos dos fármacos , Humanos , Mediadores da Inflamação/isolamento & purificação , Mediadores da Inflamação/farmacologia , Dados de Sequência Molecular , Neutrófilos/efeitos dos fármacos , Lectinas de Plantas/isolamento & purificação , Lectinas de Plantas/farmacologia , Estabilidade Proteica , Coelhos , Ratos , Ratos Wistar , Alinhamento de SequênciaRESUMO
Scorpion venoms consist of a complex of several toxins that exhibit a wide range of biological properties and actions, as well as chemical compositions, toxicity, and pharmacokinetic and pharmacodynamic characteristics. These venoms are associated with high morbility and mortality, especially among children. Victims of envenoming by a scorpion suffer a variety of pathologies, involving mainly both sympathetic and parasympathetic stimulation as well as central manifestations such as irritability, hyperthermia, vomiting, profuse salivation, tremor, and convulsion. The clinical signs and symptoms observed in humans and experimental animals are related with an excessive systemic host inflammatory response to stings and stings, respectively. Although the pathophysiology of envenomation is complex and not yet fully understood, venom and immune responses are known to trigger the release of inflammatory mediators that are largely mediated by cytokines. In models of severe systemic inflammation produced by injection of high doses of venom or venoms products, the increase in production of proinflammatory cytokines significantly contributes to immunological imbalance, multiple organ dysfunction and death. The cytokines initiate a cascade of events that lead to illness behaviors such as fever, anorexia, and also physiological events in the host such as activation of vasodilatation, hypotension, and increased of vessel permeability.
Assuntos
Mediadores da Inflamação/imunologia , Inflamação/imunologia , Venenos de Escorpião/imunologia , Animais , Citocinas/imunologia , Humanos , Inflamação/fisiopatologia , Mediadores da Inflamação/química , Venenos de Escorpião/química , Escorpiões/químicaRESUMO
Snake venom metalloproteinases (SVMPs) are widely distributed in snake venoms and play important roles in hemostatic disorders and local tissue damage that follows snakebite. The impact of SVMPs on hemostasis has been extensively studied showing diverse effects both on soluble factors and cellular components. The action of SVMPs involves catalytic and anti-adhesive properties, as well as direct cellular activation and/or the release of endogenous bioactive components. The purpose of this review is to overview the action of SVMPs on the inhibition of platelet functions; angiogenesis, particularly inducing apoptosis of endothelial cells; and regarding the pro-inflammatory reaction that follows snakebite. We discuss the structural features of the molecules that may be involved in such activities. The versatility and availability of SVMPs make them important tools for cell biology research into the mechanisms of action of endogenous metalloproteinases, for insights into cellular-matrix interactions and for clinical investigations into the treatment of snakebites.
Assuntos
Plaquetas/enzimologia , Células Endoteliais/enzimologia , Mediadores da Inflamação/fisiologia , Metaloproteases/fisiologia , Venenos de Serpentes/enzimologia , Animais , Plaquetas/patologia , Células Endoteliais/patologia , Humanos , Mediadores da Inflamação/química , Metaloproteases/química , Venenos de Serpentes/químicaRESUMO
A dialyzable low molecular weight proinflammatory factor (X (2)) from rat spleen lymphocytes was isolated through a combination of gel filtration and high voltage paper electrophoresis (HVE) and then partially characterized. It was able to potentiate the formation of carrageenin induced edema on the rat paw. Its amino acid analysis revealed Glu, Cys and Gly (1:1:1), but gammaGlu as N-terminal residue, initially suggesting oxidized glutathione (GSSG), since it showed exactly the same HV electrophoretic mobility as GSSG at pH 6.5. However, neither GSSG nor a synthetic homologue showed any proinflammatory activity. On basis of its infrared spectrum, HVE mobility and presence of a gamma-Glu-Cys-Gly (GSH) moiety, the hypothesis of identity of X (2) with leukotriene C(4) (LTC(4)) was raised. Once again it was not confirmed, since LTC(4) did not show any proinflammatory activity too, leading us to infer that, even excluding LTC(4), our data are consistent with a structure bearing a GSH moiety conjugated with a hydroxylated insaturated fatty acid chain which contributes a -COO(-) group, thus providing a final net charge of -2 at pH 6.5 and an Mr = 600-650.
Assuntos
Mediadores da Inflamação/química , Mediadores da Inflamação/isolamento & purificação , Inflamação/imunologia , Linfócitos/imunologia , Baço/imunologia , Animais , Carragenina , Cromatografia em Gel/métodos , Eletroforese/métodos , Feminino , Inflamação/induzido quimicamente , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Irritantes , Linfócitos/metabolismo , Masculino , Peso Molecular , Ratos , Ratos Wistar , Baço/citologiaRESUMO
Neste trabalho, elaboramos um estudo comparativo entre o potencial anti-inflamatório da Arnica tintura-mäe e da Arnica 6CH, frente a injeçöes de diversos agentes flogísticos no coxim plantar de ratos albinos Wistar. Os animais foram inoculados no tecido subcutâneo da pata 0,06ml de carragenina 1 por cento, ou histamina 2,5 por cento (associada ou näo à prostaglandina E, 3 por cento), ou bradicinina 0,01 por cento e o edema inflamatório foi avaliado pelo método da pletismografia