RESUMO
Dendritic cells (DCs) vaccine is a potential tool for oncoimmunotherapy. However, it is known that this therapeutic strategy has failed in solid tumors, making the development of immunoadjuvants highly relevant. Recently, we demonstrated that Phoneutria nigriventer spider venom (PnV) components are cytotoxic to glioblastoma (GB) and activate macrophages for an antitumor profile. However, the effects of these molecules on the adaptive immune response have not yet been evaluated. This work aimed to test PnV and its purified fractions in DCs in vitro. For this purpose, bone marrow precursors were collected from male C57BL6 mice, differentiated into DCs and treated with venom or PnV-isolated fractions (F1-molecules < 3 kDa, F2-3 to 10 kDa and F3->10 kDa), with or without costimulation with human GB lysate. The results showed that mainly F1 was able to activate DCs, increasing the activation-dependent surface marker (CD86) and cytokine release (IL-1ß, TNF-α), in addition to inducing a typical morphology of mature DCs. From the F1 purification, a molecule named LW9 was the most effective, and mass spectrometry showed it to be a peptide. The present findings suggest that this molecule could be an immunoadjuvant with possible application in DC vaccines for the treatment of GB.
Assuntos
Glioblastoma , Venenos de Aranha , Camundongos , Masculino , Humanos , Animais , Glioblastoma/terapia , Venenos de Aranha/farmacologia , Camundongos Endogâmicos C57BL , Diferenciação Celular , Células DendríticasRESUMO
Glioblastomas (GBs) are responsible for a higher mortality rate among gliomas, corresponding to more than 50% of them and representing a challenge in terms of therapy and prognosis. Peptide-based antineoplastic therapy is a vast and promising field, and these molecules are one of the main classes present in spider venoms. Recently, our research group demonstrated the cytotoxic effects of Phoneutria nigriventer spider venom (PnV) in GBs. The present study aimed to select the purified PnV-components with potential antineoplastic effects, as well as to compare different metabolic conditions. Human GB (NG97) cells were treated with the PnV fractions: F1 (less than 3 kDa), F2 (between 3 and 10 kDa), and F3 (greater than 10 kDa). After treatments, viability (MTT), proliferation (CFSE), death (Annexin V/propidium iodide-PI), and cell cycle (PI) assays were performed. The F1 and F2 fractions in acute periods (1 and 5 h) and low concentrations (0.1 and 1 µg/ml) showed more relevant effects and were repurified in subfractions (SF1-SF11); from these, SF3 and SF4 showed the most significant effects. The previous inhibition of mTOR by rapamycin had a synergistic effect with SFs, reducing cell viability even more significantly than the untreated control. Taken together, the results point to components present in SF3 and SF4 as potential prototypes for the development of new drugs for GB treatment and stimulate studies to use these compounds in combination therapy with a rapamycin-like activity. Future studies will be conducted to characterize, synthesize the molecules, and to evaluate the efficacy and safety in preclinical models.
RESUMO
Peptides are molecules that have emerged as crucial candidates for the development of anticancer drugs. Spider venoms are a rich source of peptides (venom peptides - VPs) with biological effects. VPs have been tested as adjuvants in the activation of cells of the immune system with the aim of improving immunotherapies for the treatment of neoplasms. In the present study, the effects of SNX-482, a peptide from the African tarantula Hysterocrates gigas, on macrophages were described. The results showed that the peptide activated M0-macrophages, increasing costimulatory molecules (CD40, CD68, CD80, CD83, CD86) involved in antigen presentation, and also augmenting the checkpoint molecules PD-L1, CTLA-4 and FAS-L; these effects were not concentration-dependent. SNX-482 also increased the release of IL-23 and upregulated the expression of ccr4, ifn-g, gzmb and pdcd1, genes important for the anticancer response. The pretreatment of macrophages with the peptide did not interfere in the modulation of T cells, and macrophages previously polarized to M1 and M2 profile did not respond to SNX-482. These findings represent the expansion of knowledge about the use of VPs in drug discovery, pointing to a potential new candidate for anticancer immunotherapy. Considering that most immunotherapies target the adaptive system, the modulation of macrophages (an innate immune cell) by SNX-482 is especially relevant.
Assuntos
Adjuvantes Imunológicos/farmacologia , Ativação de Macrófagos/efeitos dos fármacos , Venenos de Aranha/química , Aranhas/química , Animais , Antígenos CD/imunologia , Linhagem Celular Tumoral , Polaridade Celular , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Expressão Gênica , Ativação de Macrófagos/imunologia , Camundongos , Neoplasias/genética , Neoplasias/imunologia , Venenos de Aranha/farmacologiaRESUMO
BACKGROUND: Multiple sclerosis (MS) is a disease of the central nervous system where an autoimmune response leads to chronic inflammation. It represents the second leading cause of non-traumatic disability in the world, affecting mainly young adults and with high female to male incidence. At present, the causative agent in MS is unknown, preventing the development of prophylaxis policies and the understanding of how the human system copes with this complex inflammation. Tetracyclines (Tet) have attracted great attention due to their anti-inflammatory effects. Minocycline and doxycycline represent the second-generation Tet that have been largely used to treat acne and to suppress inflammation. In addition, they are safer and cheaper than other drugs currently used to treat MS. AIM: This study aims to review recent data involving the Tet minocycline and doxycycline and their therapeutic potential in MS. RELEVANCE FOR PATIENTS: Many of the drugs used to treat MS have severe side effects and are costly. Tet, on the other hand, are a safe and inexpensive class of drugs that can modulate the immune response in MS patients.
RESUMO
Immunomodulation has been considered an important approach in the treatment of malignant tumours. However, the modulation of innate immune cells remains an underexplored tool. Studies from our group demonstrated that the Phoneutria nigriventer spider venom (PnV) administration increased the infiltration of macrophage in glioblastoma, in addition to decreasing the tumour size in a preclinical model. The hypothesis that PnV would be modulating the innate immune system led us to the main objective of the present study: to elucidate the effects of PnV and its purified fractions on cultured macrophages. Results showed that PnV and the three fractions activated macrophages differentiated from bone marrow precursors. Further purification generated 23 subfractions named low weight (LW-1 to LW-12) and high weight (HW-1 to HW-11). LW-9 presented the best immunomodulatory effect. Treated cells were more phagocytic, migrated more, showed an activated morphological profile and induced an increased cytotoxic effect of macrophages on tumour cells. However, while M1-controls (LPS) increased IL-10, TNF-alpha and IL-6 release, PnV, fractions and subfractions did not alter any cytokine, with the exception of LW-9 that stimulated IL-10 production. These findings suggest that molecules present in LW-9 have the potential to be used as immunoadjuvants in the treatment of cancer.
Assuntos
Adjuvantes Imunológicos/farmacologia , Glioblastoma/terapia , Imunoterapia , Macrófagos/efeitos dos fármacos , Venenos de Aranha/farmacologia , Animais , Células Cultivadas , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , CamundongosRESUMO
BACKGROUND: Glioblastoma (GB) cells have the ability to migrate and infiltrate the normal parenchyma, leading to the formation of recurrent tumors often adjacent to the surgical extraction site. We recently showed that Phoneutria nigriventer spider venom (PnV) has anticancer effects mainly on the migration of human GB cell lines (NG97 and U-251). The present work aimed to investigate the effects of isolated components from the venom on migration, invasiveness, morphology and adhesion of GB cells, also evaluating RhoA-ROCK signaling and Na+/K+-ATPase ß2 (AMOG) involvement. METHODS: Human (NG97) GB cells were treated with twelve subfractions (SFs-obtained by HPLC from PnV). Migration and invasion were evaluated by scratch wound healing and transwell assays, respectively. Cell morphology and actin cytoskeleton were shown by GFAP and phalloidin labeling. The assay with fibronectin coated well plate was made to evaluate cell adhesion. Western blotting demonstrated ROCK and AMOG levels and a ROCK inhibitor was used to verify the involvement of this pathway. Values were analyzed by the GraphPad Prism software package and the level of significance was determinate using one-way analysis of variance (ANOVA) followed by Dunnett's multiple comparisons test. RESULTS: Two (SF1 and SF11) of twelve SFs, decreased migration and invasion compared to untreated control cells. Both SFs also altered actin cytoskeleton, changed cell morphology and reduced adhesion. SF1 and SF11 increased ROCK expression and the inhibition of this protein abolished the effects of both subfractions on migration, morphology and adhesion (but not on invasion). SF11 also increased Na+/K+-ATPase ß2. CONCLUSION: All components of the venom were evaluated and two SFs were able to impair human glioblastoma cells. The RhoA effector, ROCK, was shown to be involved in the mechanisms of both PnV components. It is possible that AMOG mediates the effect of SF11 on the invasion. Further investigations to isolate and biochemically characterize the molecules are underway.
RESUMO
Studies that show an overview of the peripheral immune response in a model of Paracoccidioides brasiliensis (Pb) infection in females are scarce in the literature. We sought to characterize the innate and adaptive immune responses in female C57BL/6 mice infected with Pb through two distinct routes of administration, intranasal and intravenous. In addition to the lung, P. brasiliensis yeast cells were observed in liver and brain tissues of females infected intravenously. To our knowledge, our study is the first to prove the presence of this pathogenic fungus in the cerebral cortex of female mice. During the initial stages of infection, augmented expression of both MHCII and CD86 was observed on the surface of CD11c+ pulmonary antigen-presenting cells (APCs) in intranasally and intravenously infected females. However, CD40 expression was downregulated in these cells. Concomitantly with increasing serum IL-10 levels, we noted that splenic dendritic cells (DCs) from both intravenously- and intranasally-infected female mice had acquired an immature phenotype. Further, increased T regulatory cell counts were observed in female mice infected via both routes, along with an increase in the infiltration of IL-10-producing CD8+ T cells into the lungs. Moreover, we noted that P. brasiliensis infection resulted in enhanced IL-10 production - by CD11c+ APCs in the lung tissue - and induction of Th17 polarization. Taken together, our results suggest that P. brasiliensis could modulates the immune response in female mice by influencing the balance between regulatory T cells (Tregs) and Th17 polarization.
Assuntos
Interações Hospedeiro-Patógeno , Contagem de Linfócitos , Paracoccidioides/imunologia , Paracoccidioidomicose/imunologia , Paracoccidioidomicose/microbiologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Animais , Citocinas/metabolismo , Feminino , Interações Hospedeiro-Patógeno/imunologia , Mediadores da Inflamação/metabolismo , Camundongos , Paracoccidioidomicose/transmissão , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismoRESUMO
Molecules from animal venoms are promising candidates for the development of new drugs. Previous in vitro studies have shown that the venom of the spider Phoneutria nigriventer (PnV) is a potential source of antineoplastic components with activity in glioblastoma (GB) cell lines. In the present work, the effects of PnV on tumor development were established in vivo using a xenogeneic model. Human GB (NG97, the most responsive line in the previous study) cells were inoculated (s.c.) on the back of RAG-/- mice. PnV (100 µg/Kg) was administrated every 48 h (i.p.) for 14 days and several endpoints were evaluated: tumor growth and metabolism (by microPET/CT, using 18F-FDG), tumor weight and volume, histopathology, blood analysis, percentage and profile of macrophages, neutrophils and NK cells isolated from the spleen (by flow cytometry) and the presence of macrophages (Iba-1 positive) within/surrounding the tumor. The effect of venom was also evaluated on macrophages in vitro. Tumors from PnV-treated animals were smaller and did not uptake detectable amounts of 18F-FDG, compared to control (untreated). PnV-tumor was necrotic, lacking the histopathological characteristics typical of GB. Since in classic chemotherapies it is observed a decrease in immune response, methotrexate (MTX) was used only to compare the PnV effects on innate immune cells with a highly immunosuppressive antineoplastic drug. The venom increased monocytes, neutrophils and NK cells, and this effect was the opposite of that observed in the animals treated with MTX. PnV increased the number of macrophages in the tumor, while did not increase in the spleen, suggesting that PnV-activated macrophages were led preferentially to the tumor. Macrophages were activated in vitro by the venom, becoming more phagocytic; these results confirm that this cell is a target of PnV components. Spleen and in vitro PnV-activated macrophages were different of M1, since they did not produce pro- and anti-inflammatory cytokines. Studies in progress are selecting the venom molecules with antitumor and immunomodulatory effects and trying to better understand their mechanisms. The identification, optimization and synthesis of antineoplastic drugs from PnV molecules may lead to a new multitarget chemotherapy. Glioblastoma is associated with high morbidity and mortality; therefore, research to develop new treatments has great social relevance. Natural products and their derivatives represent over one-third of all new molecular entities approved by FDA. However, arthropod venoms are underexploited, although they are a rich source of new molecules. A recent in vitro screening of the Phoneutria nigriventer spider venom (PnV) antitumor effects by our group has shown that the venom significantly affected glioblastoma cell lines. Therefore, it would be relevant to establish the effects of PnV on tumor development in vivo, considering the complex neoplastic microenvironment. The venom was effective at impairing tumor development in murine xenogeneic model, activating the innate immune response and increasing tumor infiltrating macrophages. In addition, PnV activated macrophages in vitro for a different profile of M1. These activated PnV-macrophages have potential to fight the tumor without promoting tumorigenesis. Studies in progress are selecting the venom molecules with antitumor and immunomodulatory effects and trying to better understand their mechanisms. We aim to synthesize and carry out a formulation with these antineoplastic molecules for clinical trials. Spider venom biomolecules induced smaller and necrotic xenogeneic GB; spider venom activated the innate immune system; venom increased blood monocytes and the migration of macrophages to the tumor; activated PnV-macrophages have a profile different of M1 and have a potential to fight the tumor without promote tumorigenesis.
Assuntos
Antineoplásicos/uso terapêutico , Glioblastoma/tratamento farmacológico , Venenos de Aranha/uso terapêutico , Animais , Linhagem Celular Tumoral , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Imunofluorescência , Glioblastoma/imunologia , Humanos , Imunidade/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transplante de Neoplasias , Aranhas , Microtomografia por Raio-XRESUMO
The mechanisms of cancer involve changes in multiple biological pathways. Multitarget molecules, which are components of animal venoms, are therefore a potential strategy for treating tumors. The objective of this study was to screen the effects of Phoneutria nigriventer spider venom (PnV) on tumor cell lines. Cultured human glioma (NG97), glioblastoma (U-251) and cervix adenocarcinoma (HeLa) cells, and nontumor mouse fibroblasts (L929) were treated with low (14 µg/ml) and high (280 µg/ml) concentrations of PnV, and analyzed through assays for cell viability (thiazolyl blue tetrazolium blue), proliferation (carboxyfluorescein succinimidyl ester), death (annexin V/propidium iodide [Pi]), the cell cycle (Pi), and migration (wound healing and transwell assay). The venom decreased the viability of U-251 cells, primarily by inducing cell death, and reduced the viability of NG97 cells, primarily by inhibiting the cell cycle. The migration of all the tumor cell lines was delayed when treated with venom. The venom significantly affected all the tumor cell lines studied, with no cytotoxic effect on normal cells (L929), although the nonglial tumor cell (HeLa) was less sensitive to PnV. The results of the current study suggest that PnV may be composed of peptides that are highly specific for the multiple targets involved in the hallmarks of cancer. Experiments are underway to identify these molecules.
Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Glioma/tratamento farmacológico , Venenos de Aranha/farmacologia , Neoplasias do Colo do Útero/tratamento farmacológico , Adenocarcinoma/patologia , Animais , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/patologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Glioma/patologia , Células HeLa , Humanos , Masculino , Camundongos , Necrose , Invasividade Neoplásica , Neoplasias do Colo do Útero/patologiaRESUMO
The mechanisms of cancer involve changes in multiple biological pathways. Multitarget molecules, which are components of animal venoms, are therefore a potential strategy for treating tumors. The objective of this study was to screen the effects of Phoneutria nigriventer spider venom (PnV) on tumor cell lines. Cultured human glioma (NG97), glioblastoma (U-251) and cervix adenocarcinoma (HeLa) cells, and nontumor mouse fibroblasts (L929) were treated with low (14?µg/ml) and high (280?µg/ml) concentrations of PnV, and analyzed through assays for cell viability (thiazolyl blue tetrazolium blue), proliferation (carboxyfluorescein succinimidyl ester), death (annexin V/propidium iodide [Pi]), the cell cycle (Pi), and migration (wound healing and transwell assay). The venom decreased the viability of U-251 cells, primarily by inducing cell death, and reduced the viability of NG97 cells, primarily by inhibiting the cell cycle. The migration of all the tumor cell lines was delayed when treated with venom. The venom significantly affected all the tumor cell lines studied, with no cytotoxic effect on normal cells (L929), although the nonglial tumor cell (HeLa) was less sensitive to PnV. The results of the current study suggest that PnV may be composed of peptides that are highly specific for the multiple targets involved in the hallmarks of cancer. Experiments are underway to identify these molecules.
RESUMO
PhTx2 is the most toxic fraction from the venom of the spider Phoneutria nigriventer, being responsible to sodium entry into cortical synaptosomes, increasing the release of neurotransmitters, such as l-glutamate (L-Glu) and; acetylcholine. In this study, we investigated the action of a toxin purified from; PhTx2 fraction, called PnTx2-6 or δ-CNTX-Pn2a, on L-Glu release from rat; brain cortex synaptosomes, as well as its ability to induce blood-brain barrier permeability. PnTx2-6 increased L-Glu release from rat cortical brain synaptosomes in a time- and dose-dependent manner (EC50â¯=â¯â¼20â¯nM; Tmâ¯=â¯16min), as measured by a fluorimetric method. The increase of L-Glu by PnTx2-6 was inhibited by tetrodotoxin. And partially inhibited by EGTA. Calcium channel blockers ω-conotoxin MVIIC (P/Q-types) and ω-conotoxin GVIA (N-type), were able to reduce the PnTx2-6-induced release of L-Glu, while nifedipine (L-type) did not show any inhibition. These findings suggest that thew release of L-Glu by PnTx2-6 is due its primary action on sodium channels, well-known to be target of this toxin. PnTx2-6 is able to potentiate penile erection and this effect may be related with the release of l-glutamate from the CNS, besides a local effect on corpus carvenosum, as previously shown by our group. If L-Glu release and penile erection potentiation are indeed correlated, then this toxin should be able to cross the blood brain barrier (BBB). Results by immunoblotting assays indicated a change in the expression of proteins associated with the paracellular and transcellular transport at the blood-brain barrier, suggesting a BBB dysfunction mediated by PnTx2-6. Therefore, PnTx2-6 may induce the release l-glutamate in the central nervous system, when injected peripherally.
Assuntos
Canais de Cálcio/metabolismo , Ácido Glutâmico/metabolismo , Peptídeos/farmacologia , Canais de Sódio/metabolismo , Venenos de Aranha/química , Sinaptossomos/efeitos dos fármacos , Animais , Barreira Hematoencefálica , Encéfalo , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Venenos de Aranha/farmacologia , Aranhas/fisiologia , Sinaptossomos/metabolismoRESUMO
Background and Aim: Animal venoms comprise a mix of bioactive molecules with high affinity for multiple targets in cells and tissues. Scorpion and spider venoms and purified peptides exhibit significant effects on cancer cells, encompassing four potential mechanisms: 1) induction of cell cycle arrest, growth inhibition, and apoptosis; 2) inhibition of angiogenesis; 3) inhibition of invasion and metastasis; and 4) blocking of specific transmembrane channels. Tumor biology is complex and entails many intertwined processes, as reflected in the putative hallmarks of cancer. This complexity, however, gives rise to numerous (potential) pharmacological intervention sites. Molecules that target multiple proteins or pathways, such as components of animal venoms, may therefore be effective anti-cancer agents. The objective of this review was to address the anti-cancer properties and in vitro mechanisms of scorpion and spider venoms and toxins, and highlight current obstacles in translating the preclinical research to a clinical setting. Relevance for patients: Cancer is a considerable global contributor to disease-related death. Despite some advances being made, therapy remains palliative rather than curative for the majority of cancer indications. Consequently, more effective therapies need to be devised for poorly responding cancer types to optimize clinical cancer management. Scorpion and spider venoms may occupy a role in the development of improved anti-cancer modalities.
RESUMO
Astrocytes are effectively involved in the pathophysiological processes in the central nervous system (CNS) and may contribute to or protect against development of inflammatory and degenerative diseases. Sildenafil is a potent and selective phosphodiesterase-5 (PDE-5) inhibitor, which induces cyclic GMP accumulation. However, the mechanisms of actions on glial cells are not clear. The aim of the present work is to evaluate the role of sildenafil in lipopolysaccharide (LPS)-stimulated astrocytes. The cytoskeleton integrity and Ca(2+) waves were assessed as indicators of inflammatory state. Two main groups were done: (A) one prevention and (B) one restoration. Each of these groups: A1: control; A2: LPS for 24h; A3: sildenafil 1 or 10µM for 4h and then sildenafil 1 or 10µM+LPS for 24h. B1: control; B2: LPS for 24h; B3: LPS for 24h and then LPS+sildenafil 1 or 10µM for 24h. Cytoskeleton integrity was analyzed through GFAP immunolabeling and actin labeling with an Alexa 488-conjugated phalloidin probe. Calcium responses were assessed through a Ca(2+)-sensitive fluorophore Fura-2/AM. The results show that both preventive and restorative treatments with sildenafil (in both concentrations) reduced the Ca(2+) responses in intensity and induced a more organized actin fiber pattern, compared to LPS treated cells. This work demonstrated for the first time that astrocytes are a key part of the sildenafil protective effects in the CNS.
Assuntos
Astrócitos/efeitos dos fármacos , Sinalização do Cálcio/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Encefalite/prevenção & controle , Inibidores da Fosfodiesterase 5/farmacologia , Citrato de Sildenafila/farmacologia , Citoesqueleto de Actina/efeitos dos fármacos , Citoesqueleto de Actina/metabolismo , Trifosfato de Adenosina/farmacologia , Animais , Astrócitos/metabolismo , Células Cultivadas , Encefalite/induzido quimicamente , Encefalite/metabolismo , Lipopolissacarídeos , RatosRESUMO
Bites from genus Phoneutria (Ctenidae, Araneomorpha) are the second most frequent source of spider accidents in Southeast Brazil. Severe envenoming from Phoneutria nigriventer produces vision disturbance, tremor and convulsion, suggesting that the CNS is involved; however, the mechanisms by which P. nigriventer venom (PNV) affects the CNS remain poorly understood. The present study aimed to investigate whether PNV directly impairs astrocytes. Cultured astrocytes were exposed to PNV, and intracellular Ca(2+) release and signaling were measured (Fura-2/AM), Na(+)/K(+)-ATPase and Toll-like receptor 4 (TLR4) involvement were investigated, actin filaments were stained (Alexa™ 488-conjugated phalloidin probe), the G-actin/F-actin ratio was determined, and the expression level of connexin 43 (Cx43) was assessed. Incubation in Ca(2+)-free buffer did not change the Ca(2+) responses. However, pre-incubation in thapsigargin/caffeine completely abolished these responses, suggesting that PNV-evoked Ca(2+) transients were from intracellular Ca(2+) stores. Pretreatment with a Na(+)/K(+)-ATPase antagonist (ouabain) or a TLR4 antagonist (LPS-RS) decreased or increased the Ca(2+)-evoked transients, respectively. Astrocytes showed altered actin filament structure after PNV exposure. PNV treatment increased the expression levels of Na(+)/K(+)-ATPase and Cx43 but decreased those of TLR4. The present results suggest that PNV directly affects astrocytes. Na(+)/K(+)-ATPase may thus represent a more specific drug target for controlling the neurotoxicity of PNV.
Assuntos
Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Neuropeptídeos/toxicidade , Neurotoxinas/toxicidade , Citoesqueleto de Actina/efeitos dos fármacos , Citoesqueleto de Actina/metabolismo , Citoesqueleto de Actina/patologia , Animais , Astrócitos/patologia , Células Cultivadas , Feminino , Masculino , Neuropeptídeos/isolamento & purificação , Neurotoxinas/isolamento & purificação , Ratos , Ratos Sprague-Dawley , AranhasRESUMO
A satisfação relacional representa um construto de pertinência reconhecida para a avaliação rela-cional e em estreita conexão com diversas valências da saúde. A Global Measure of Relationship Satisfaction (GMREL) é formada por cinco itens e pretende avaliar a satisfação global com o companheiro/a no contexto de uma relação íntima. Foram estudadas as evidências de validade de construto e precisão dos escores desta escala em três amostras da população portuguesa, nomeadamente uma amostra clínica de pessoas com problemas relacionais (N = 56), uma amostra comunitária de pessoas sem estes problemas (N = 95) e uma amostra da comunidade de ambos os géneros (N= 669). A Escala de Avaliação da Satisfação em Áreas da Vida Conjugal foi empregue para investigar a validade convergente do instrumento, a Body Appearance Cognitive Distraction Scale para a validade divergente e, por fim, o estudo da Roc Curve com a amostra clínica e da comunidade para a validade discriminante. Os resultados indicam que a escala apresenta boas qualidades psicométricas para utilização em contexto clínico e de investigação.
Relationship satisfaction represents a well-known, pertinent construct for relationship assessment with strong connection to several health ranges. The Global Measure of Relationship Satisfaction (GMREL) is composed of five items and aims to evaluate the global satisfaction with the partner in an intimate relationship context. The purpose of this study was to observe the psychometric qualities of this scale in three Portuguese samples, namely a clinical sample of individuals with marital problems (N = 56), a normative sample of individuals without these problems (N = 95) and a community sample of both genders (N = 669). The Marital Life Areas Satisfaction Evaluation Scale was used to investigate the instrument's convergent validity; the Body Appearance Cognitive Distraction Scale for the divergent validity, and the Roc Curve study of clinical and community samples was used to assess the discriminant validity. The results show that the instrument presents good psychometric qualities for clinical and investigation purposes.
Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Pessoa de Meia-Idade , Cônjuges/psicologia , Satisfação Pessoal , Relações Interpessoais , Psicometria/instrumentaçãoRESUMO
A satisfação relacional representa um construto de pertinência reconhecida para a avaliação rela-cional e em estreita conexão com diversas valências da saúde. A Global Measure of Relationship Satisfaction (GMREL) é formada por cinco itens e pretende avaliar a satisfação global com o companheiro/a no contexto de uma relação íntima. Foram estudadas as evidências de validade de construto e precisão dos escores desta escala em três amostras da população portuguesa, nomeadamente uma amostra clínica de pessoas com problemas relacionais (N = 56), uma amostra comunitária de pessoas sem estes problemas (N = 95) e uma amostra da comunidade de ambos os géneros (N= 669). A Escala de Avaliação da Satisfação em Áreas da Vida Conjugal foi empregue para investigar a validade convergente do instrumento, a Body Appearance Cognitive Distraction Scale para a validade divergente e, por fim, o estudo da Roc Curve com a amostra clínica e da comunidade para a validade discriminante. Os resultados indicam que a escala apresenta boas qualidades psicométricas para utilização em contexto clínico e de investigação.(AU)
Relationship satisfaction represents a well-known, pertinent construct for relationship assessment with strong connection to several health ranges. The Global Measure of Relationship Satisfaction (GMREL) is composed of five items and aims to evaluate the global satisfaction with the partner in an intimate relationship context. The purpose of this study was to observe the psychometric qualities of this scale in three Portuguese samples, namely a clinical sample of individuals with marital problems (N = 56), a normative sample of individuals without these problems (N = 95) and a community sample of both genders (N = 669). The Marital Life Areas Satisfaction Evaluation Scale was used to investigate the instrument's convergent validity; the Body Appearance Cognitive Distraction Scale for the divergent validity, and the Roc Curve study of clinical and community samples was used to assess the discriminant validity. The results show that the instrument presents good psychometric qualities for clinical and investigation purposes.(AU)
Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Cônjuges/psicologia , Satisfação Pessoal , Reprodutibilidade dos Testes , Relações Interpessoais , Psicometria/instrumentaçãoRESUMO
The thymus plays an important role shaping the T cell repertoire in the periphery, partly, through the elimination of inflammatory auto-reactive cells. It has been shown that, during Plasmodium berghei infection, the thymus is rendered atrophic by the premature egress of CD4+CD8+ double-positive (DP) T cells to the periphery. To investigate whether autoimmune diseases are affected after Plasmodium berghei NK65 infection, we immunized C57BL/6 mice, which was previously infected with P. berghei NK65 and treated with chloroquine (CQ), with MOG35-55 peptide and the clinical course of Experimental Autoimmune Encephalomyelitis (EAE) was evaluated. Our results showed that NK65+CQ+EAE mice developed a more severe disease than control EAE mice. The same pattern of disease severity was observed in MOG35-55-immunized mice after adoptive transfer of P. berghei-elicited splenic DP-T cells. The higher frequency of IL-17+- and IFN-γ+-producing DP lymphocytes in the Central Nervous System of these mice suggests that immature lymphocytes contribute to disease worsening. To our knowledge, this is the first study to integrate the possible relationship between malaria and multiple sclerosis through the contribution of the thymus. Notwithstanding, further studies must be conducted to assert the relevance of malaria-induced thymic atrophy in the susceptibility and clinical course of other inflammatory autoimmune diseases.
Assuntos
Encefalomielite Autoimune Experimental/imunologia , Inflamação/imunologia , Malária/imunologia , Esclerose Múltipla/imunologia , Timo/imunologia , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Cloroquina/administração & dosagem , Encefalomielite Autoimune Experimental/microbiologia , Inflamação/microbiologia , Interferon gama/biossíntese , Interferon gama/imunologia , Malária/complicações , Malária/microbiologia , Camundongos , Esclerose Múltipla/complicações , Esclerose Múltipla/microbiologia , Glicoproteína Mielina-Oligodendrócito/administração & dosagem , Fragmentos de Peptídeos/administração & dosagem , Plasmodium berghei/imunologia , Plasmodium berghei/patogenicidade , Linfócitos T Reguladores/imunologiaRESUMO
Severe accidents caused by the "armed" spider Phoneutria nigriventer cause neurotoxic manifestations in victims. In experiments with rats, P. nigriventer venom (PNV) temporarily disrupts the properties of the BBB by affecting both the transcellular and the paracellular route. However, it is unclear how cells and/or proteins participate in the transient opening of the BBB. The present study demonstrates that PNV is a substrate for the multidrug resistance protein-1 (MRP1) in cultured astrocyte and endothelial cells (HUVEC) and increases mrp1 and cx43 and down-regulates glut1 mRNA transcripts in cultured astrocytes. The inhibition of nNOS by 7-nitroindazole suggests that NO derived from nNOS mediates some of these effects by either accentuating or opposing the effects of PNV. In vivo, MRP1, GLUT1 and Cx43 protein expression is increased differentially in the hippocampus and cerebellum, indicating region-related modulation of effects. PNV contains a plethora of Ca(2+), K(+) and Na(+) channel-acting neurotoxins that interfere with glutamate handling. It is suggested that the findings of the present study are the result of a complex interaction of signaling pathways, one of which is the NO, which regulates BBB-associated proteins in response to PNV interference on ions physiology. The present study provides additional insight into PNV-induced BBB dysfunction and shows that a protective mechanism is activated against the venom. The data shows that PNV has qualities for potential use in drug permeability studies across the BBB.
Assuntos
Venenos de Aranha/toxicidade , Animais , Astrócitos/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Permeabilidade Capilar/efeitos dos fármacos , Células Cultivadas , Cerebelo/efeitos dos fármacos , Cerebelo/metabolismo , Conexina 43/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Masculino , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Ratos Wistar , AranhasRESUMO
Dendritic cells (DCs) are professional antigen-presenting cells specifically targeted during Plasmodium infection. Upon infection, DCs show impaired antigen presentation and T-cell activation abilities. In this study, we aimed to evaluate whether cellular extracts obtained from Plasmodium berghei-infected erythrocytes (PbX) modulate DCs phenotypically and functionally and the potential therapeutic usage of PbX-modulated DCs in the control of experimental autoimmune encephalomyelitis (EAE, the mouse model for human multiple sclerosis). We found that PbX-treated DCs have impaired maturation and stimulated the generation of regulatory T cells when cultured with naive T lymphocytes in vitro. When adoptively transferred to C57BL/6 mice the EAE severity was reduced. Disease amelioration correlated with a diminished infiltration of cytokine-producing T cells in the central nervous system as well as the suppression of encephalitogenic T cells. Our study shows that extracts obtained from P. berghei-infected erythrocytes modulate DCs towards an immunosuppressive phenotype. In addition, the adoptive transfer of PbX-modulated DCs was able to ameliorate EAE development through the suppression of specific cellular immune responses towards neuro-antigens. To our knowledge, this is the first study to present evidence that DCs treated with P. berghei extracts are able to control autoimmune neuroinflammation.
Assuntos
Transferência Adotiva , Células Dendríticas/transplante , Terapia de Imunossupressão/métodos , Neurite Autoimune Experimental/prevenção & controle , Plasmodium berghei/imunologia , Linfócitos T Reguladores/imunologia , Animais , Células Cultivadas , Técnicas de Cocultura , Citocinas/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Células Dendríticas/parasitologia , Feminino , Imunidade Celular , Camundongos , Camundongos Endogâmicos C57BL , Neurite Autoimune Experimental/imunologia , Neurite Autoimune Experimental/metabolismo , Neurite Autoimune Experimental/parasitologia , Fenótipo , Linfócitos T Reguladores/metabolismo , Linfócitos T Reguladores/parasitologia , Fatores de TempoRESUMO
We recently demonstrated that sildenafil reduces the expression of cytokines, COX-2, and GFAP in a demyelinating model induced in wild-type (WT) mice. Herein, the understandings of the neuroprotective effect of sildenafil and the mediation of iNOS/NO system on inflammatory demyelination induced by cuprizone were investigated. The cerebella of iNOS(-/-) mice were examined after four weeks of treatment with cuprizone alone or combined with sildenafil. Cuprizone increased GFAP, Iba-1, TNF- α , COX-2, IL-1 ß , and IFN- γ expression, decreased expression of glutathione S-transferase pi (GSTpi), and damaged myelin in iNOS(-/-) mice. Sildenafil reduced Iba-1, IFN- γ , and IL-1 ß levels but had no effect on the expression of GFAP, TNF- α , and COX-2 compared to the cuprizone group. Sildenafil elevated GSTpi levels and improved the myelin structure/ultrastructure. iNOS(-/-) mice suffered from severe inflammation following treatment with cuprizone, while WT mice had milder inflammation, as found in the previous study. It is possible that inflammatory regulation through iNOS-feedback is absent in iNOS(-/-) mice, making them more susceptible to inflammation. Sildenafil has at least a partial anti-inflammatory effect through iNOS inhibition, as its effect on iNOS(-/-) mice was limited. Further studies are required to explain the underlying mechanism of the sildenafil effects.