ABSTRACT
Resumen Los macrófagos son células fagocíticas que activan a la sintasa de óxido nítrico (SON) y la NADPH oxidasa con el objetivo de eliminar agentes que reconocen como extraños. Además, participan en el desarrollo y mantenimiento de la respuesta inflamatoria. Tibolona (Tb), a través de sus metabolitos, tiene actividad estrogénica, progestagénica y androgénica. Es utilizada como alternativa de la terapia hormonal de la menopausia, que además disminuye marcadores de inflamación. El objetivo de este estudio fue describir el efecto de Tb sobre la expresión de las interleucinas I, 6, 10 y TNF-α así como la actividad de la NADPH oxidasa del macrófago. Se utilizó la línea celular THP-1, se diferenció a macrófago, y se evaluó la actividad de NADPH oxidasa por el ensayo de NBT y la expresión de IL-1β, IL-6, TNF-α e IL-10 por RT-qPCR. Se encontró que Tb regula la actividad enzimática, así como la expresión de citocinas ante un estímulo proinflamatorio. Por lo que se concluye que Tb favorece la actividad antiinflamatoria del macrófago. Estos resultados contribuyen a la descripción de los mecanismos de acción de este fármaco. Además, se propone al macrófago como un blanco de regulación del proceso inflamatorio por acción de Tb. Se sugiere que se determine la expresión proteica de las citocinas por otras técnicas, tales como western blot, ELISA, o citometría de flujo; así como la actividad de SON.
Abstract Macrophages are phagocytic cells that activate NOS and NADPH oxidase to eliminate agents that recognize like strangers, also participate in development and maintain of inflammatory response. In other hand, tibolone (Tb) has three main metabolites, which have an estrogenic, prostagenic and androgenic activity. This drug is a hormonal therapy to treat symptoms of menopause, with ability to decrease inflammation markers. The aim of this study is to describe the effect of Tb on macrophage activity. This study was carried out on differentiated macrophage THP-1 cell line used. NADPH oxidase activity by NBT assay and expression of IL-1β, IL-6, TNF-α and IL-10 by RT-qPCR were measured. It has been observed that Tb regulates the enzymatic activity, as well as the cytokines expression in the cells that received a proinflammatory stimulus; these results contribute to description of mechanism of action of this drug. The results suggest that macrophage could be a target for antiinflammatory action of Tb. Its remain to investagate the protein expression of cytokines and activity of iNOS.
ABSTRACT
BACKGROUND: In the central nervous system, interleukin-10 (IL-10) provides trophic and survival effects directly on neurons, modulates neurite plasticity, and has a pivotal importance in the neuronal regeneration in neurodegenerative and neuroinflammatory conditions. This cytokine is primarily produced by glial cells and has beneficial effects on the neuronal viability. However, the mechanisms of IL-10-elicited neuroprotection are not clear. RESULTS: Membrane preparations, isolated from wild-type (Wt) and IL-10 knockout (KO) mice brain were used in this study. It has been shown that compared to wild-type mice, in IL-10 KO mice brain, the amount of immunoglobulin binding protein (BiP) is greatly increased, whereas the content of sigma receptor-1 (SigR1) is not changed significantly. Co-immunoprecipitation experiments have shown that the association of SigR1 with small GTPase Rac1 (Ras-related C3 botulinum toxin substrate 1), NR2B subunit of NMDA-receptor (NMDAR) and inositol-3-phosphate receptor (IP3R) is higher in the IL-10 KO mice brain than in the Wt mice brain. Besides, we have found that either glutamate or sigma ligands, separately or together, do not change glutamate-induced NADPH-oxidase (NOX) activity in Wt-type mice brain membrane preparations, whereas in IL-10 KO mice high concentration of glutamate markedly increases the NOX-dependent production of reactive oxygen species (ROS). Glutamate-dependent ROS production was decreased to the normal levels by the action of sigma-agonists. CONCLUSIONS: It has been concluded that IL-10 deprivation, at least in part, can lead to the induction of ER-stress, which causes BiP expression and SigR1 redistribution between components of endoplasmic reticulum (ER) and plasma membrane. Moreover, IL-10 deficiency can change the specific organization of NMDAR, increasing the surface expression of SigR1-sensitive NR2B-containing NMDAR. In these conditions, glutamate-dependent ROS production is greatly increased leading to the initiation of apoptosis. In this circumstances, sigma-ligands could play a preventive role against NMDA receptor-mediated excitotoxicity.
Subject(s)
Animals , Male , Mice , Brain/metabolism , Interleukin-10/genetics , Receptors, sigma/metabolism , Glutamic Acid/metabolism , NADPH Oxidases/metabolism , Cell Membrane/metabolism , Receptors, sigma/classification , Receptors, sigma/agonists , Reactive Oxygen Species/analysis , Reactive Oxygen Species/metabolism , Receptors, N-Methyl-D-Aspartate/classification , Receptors, N-Methyl-D-Aspartate/metabolism , rac1 GTP-Binding Protein/metabolism , Immunoprecipitation , Endoplasmic Reticulum/metabolism , Inositol 1,4,5-Trisphosphate Receptors/metabolism , Gene Knockdown Techniques , Heat-Shock Proteins/metabolism , Mice, Inbred C57BL , Neurons/metabolismABSTRACT
Neurodegenerative disorders are undoubtedly an increasing problem in the health sciences, given the increase of life expectancy and occasional vicious life style. Despite the fact that the mechanisms of such diseases are far from being completely understood, a large number of studies that derive from both the basic science and clinical approaches have contributed substantial data in that direction. In this review, it is discussed several frontiers of basic research on Parkinson´s and Alzheimer´s diseases, in which research groups from three departments of the Institute of Biomedical Sciences of the University of São Paulo have been involved in a multidisciplinary effort. The main focus of the review involves the animal models that have been developed to study cellular and molecular aspects of those neurodegenerative diseases, including oxidative stress, insulin signaling and proteomic analyses, among others. We anticipate that this review will help the group determine future directions of joint research in the field and, more importantly, set the level of cooperation we plan to develop in collaboration with colleagues of the Nucleus for Applied Neuroscience Research that are mostly involved with clinical research in the same field.
Os transtornos neurodegenerativos são, sem dúvida, um problema crescente nas ciências da saúde, dado o aumento da expectativa de vida e de estilos de vida pouco saudáveis. Embora os mecanismos de tais doenças ainda estejam longe de ser esclarecidos, vários estudos que derivam tanto da ciência básica quanto de abordagens clínicas contribuíram nessa direção. Na presente revisão, são discutidas linhas de frente da pesquisa básica sobre as doenças de Parkinson e Alzheimer, em que grupos de pesquisas de três departamentos do Instituto de Ciências Biomédicas da Universidade de São Paulo estão envolvidos em um esforço multidisciplinar. O foco principal desta revisão envolve os modelos animais desenvolvidos para se estudar os aspectos celulares e moleculares daquelas doenças neurodegenerativas, incluindo o estresse oxidativo, a sinalização da insulina e as análises proteômicas, dentre outros. Antecipamos que esta revisão irá auxiliar o grupo a determinar as futuras direções da pesquisa conjunta nessa área e, o mais importante, estabelecer o nível de cooperação que planejamos desenvolver juntamente com colegas do Núcleo de Apoio à Pesquisa em Neurociência Aplicada que estão envolvidos com pesquisa clínica na mesma área.
Subject(s)
Animals , Humans , Alzheimer Disease/metabolism , Parkinson Disease/metabolism , Alzheimer Disease/etiology , Biomarkers/analysis , Brain/pathology , Disease Models, Animal , Exercise/physiology , NADPH Oxidases/metabolism , Oxidative Stress/physiology , Parkinson Disease/etiology , Peptides/analysis , ProteomicsABSTRACT
Human promyelocytic leukemia cells (HL-60) have been used as a model system in which to study the effects of protein phosphatase inhibitors on NADPH-oxidase activation. Since O2- is generated by NADPH-oxidase, we examined the effect of calyculin A pretreatment on oxidase activation in response to various agonists. When Me2SO-differentiated HL-60 cells were treated with calyculin A prior to the addition of phorbol 12-myristate 13-acetate (PMA), O2- production was inhibited; however, calyculin A enhanced O2- production by N-formyl-methionyl-leucyl-phenylalanine (FMLP). The decreased O2- production seen with calyculin A pretreatment followed by PMA may be due to diminished translocation of the p47-phox and p67-phox, cytosolic components of the oxidase, and inhibition of arachidonic acid release. Interestingly calyculin A pretreatment followed by either agonist significantly enhanced mitogen-activated-protein kinase (MAPK) activity. The differential effects of pretreatment with calyculin A on subsequent oxidase stimulation elicited by FMLP or PMA provide further evidence for substantial heterogeneity in the activation of the respiratory burst.