RESUMO
BACKGROUND: Adult polycystic kidney disease (ADPKD) still represents a major cause of renal failure and intracranial aneurisms (IA) have a higher prevalence in ADPKD than in the general population. Current guidelines suggest performing brain MRI only in the subjects with a positive familiar history of IAs or subarachnoid hemorrhage (SAH). This is a retrospective case-control analysis to evaluate the usefulness of a MR screening program in ADPKD patients. METHODS: We retrospectively analyzed all ADPKD patients followed in our outpatient clinic between 2016 and 2019 who underwent a brain MRI screening. We evaluated the presence of IAs and others brain abnormalities and compared our results with a non-ADPKD population (nâ¯= 300). We performed univariate and multivariate regression analysis to evaluate if general and demographic features, laboratory findings, clinical parameters and genetic test results correlated with IAs or other brain abnormalities presence. RESULTS: Among the patients evaluated 17 out of 156 (13.6%) ADPKD patients had IAs, compared to 16 out of 300 (5.3%) non-ADPKD controls (pâ¯< 0.005). Considering ADPKD patients presenting IAs, 12 (70.6%) had no family history for IAs or SAH. Genetic analysis was available for 97 patients: in the sub-population with IAs, 13 (76.5%) presented a PKD1 mutation and none a PKD2 mutation. We found that arachnoid cysts (AC) (pâ¯< 0.001) and arterial anatomical variants (pâ¯< 0.04) were significantly more frequent in ADPKD patients. CONCLUSION: In our population ADPKD patients showed a higher prevalence of IAs, AC and arterial variants compared to non-ADPKD. Most of the IAs were found in patients presenting a PKD1 mutation. We found a significant number of alterations even in those patients without a family history of IAs or SAH. The practice of submitting only patients with familial IAs or kidney transplantation candidates to MRI scan should be re-evaluated.
Assuntos
Rim Policístico Autossômico Dominante , Adulto , Encéfalo , Humanos , Mutação , Rim Policístico Autossômico Dominante/diagnóstico por imagem , Rim Policístico Autossômico Dominante/genética , Estudos Retrospectivos , Canais de Cátion TRPP/genéticaRESUMO
AIM: To evaluate the efficacy of selective and nonselective inhibitors of cyclooxygenase-2 enzymes in the treatment of experimental apical periodontitis induced by bacterial lipopolysaccharide (LPS) in vivo in a mouse model. METHODOLOGY: Thirty-six C57BL/6 mice were used. After access cavity preparation, a solution containing E. coli LPS (1.0 µg µL-1 ) was inoculated into the root canals of the mandibular and maxillary right first molars (n = 72) After 30 days, apical periodontitis was established and the animals were systemically treated with celecoxib, a selective COX-2 inhibitor (15 mg kg-1 ), or indomethacin, a nonselective COX-2 inhibitor (5 mg kg-1 ), for 7 and 14 days. Blocks containing teeth and bone were removed for histopathological and histometric analyses (haematoxylin and eosin), evaluation of osteoclasts numbers (tartrate-resistant acid phosphatase enzyme - TRAP) and immunohistochemistry for RANK, RANKL and OPG. Gene expression was performed using reverse transcription and real-time polymerase chain reaction (qRT-PCR) for RANK, RANKL, OPG, TRAP, MMP-9, cathepsin K and calcitonin receptor. Histopathological, histometric, TRAP, immunohistochemistry and qRT-PCR data were evaluated using Kruskal-Wallis followed by Dunn's test (α = 0.05). RESULTS: Systemic administration of celecoxib for 7 and 14 days prevented periapical bone resorption (P < 0.0001), differently from indomethacin that exacerbated bone resorption at 7 days (P < 0.0001) or exerted no effect at 14 days (P = 0.8488). Celecoxib treatment reduced osteoclast formation in apical periodontitis, regardless of the period of treatment (P < 0.0001 for 7 days and P = 0.026 for 14 days). Administration of celecoxib or indomethacin differentially modulated the expression of genes involved in bone resorption. At 7 days, celecoxib and indomethacin treatment significantly inhibited expression of mRNA for cathepsin K (P = 0.0005 and P = 0.016, respectively) without changing TRAP, MMP-9 and calcitonin receptor gene expression. At 14 days, celecoxib significantly inhibited expression of mRNA for MMP-9 (P < 0.0001) and calcitonin receptor (P = 0.004), whilst indomethacin exerted no effect on MMP-9 (P = 0.216) and calcitonin receptor (P = 0.971) but significantly augmented cathepsin K gene expression (P = 0.001). CONCLUSIONS: The selective COX-2 inhibitor celecoxib reduced osteoclastogenic signalling and activity that dampened bone resorption in LPS-induced apical periodontitis in mice, with greater efficacy than the nonselective inhibitor indomethacin.
Assuntos
Reabsorção Óssea , Lipopolissacarídeos , Animais , Reabsorção Óssea/tratamento farmacológico , Celecoxib/farmacologia , Celecoxib/uso terapêutico , Escherichia coli , Camundongos , Camundongos Endogâmicos C57BL , Osteoclastos , Ligante RANKRESUMO
BACKGROUND AND PURPOSE: The association of arterial tortuosity and connective tissue diseases is widely reported in the literature, but only a few studies were based on a quantitative evaluation of this arterial phenotype, and none of the latter examined the intracranial vasculature. The aim of this study was to evaluate the degree of intracranial arterial tortuosity in patients with Marfan syndrome and those with Loeys-Dietz syndrome, and to assess its usefulness in the differential diagnosis. MATERIALS AND METHODS: We performed a retrospective analysis of 68 patients with genetically confirmed Marfan syndrome (n = 36) or Loeys-Dietz syndrome (n = 32), who underwent at least 1 MRA of the brain at our institution. Fifty-two controls were randomly selected among patients who presented with headache and without any known comorbidity. Tortuosity indexes of 4 intracranial arterial segments were measured on a 3D volume-rendered angiogram by using the following formula: [Formula: see text]. RESULTS: Both Marfan syndrome and Loeys-Dietz syndrome showed a significantly higher tortuosity index compared with controls in all examined vessels. The tortuosity index of the vertebrobasilar system showed an excellent interrater reliability (intraclass correlation coefficient, 0.99) and was the strongest independent predictor of Loeys-Dietz syndrome in patients with connective tissue disease (P = .002), with a 97% specificity for this pathology when its value was > 60. CONCLUSIONS: The tortuosity index of intracranial arteries is an easily calculated and highly reproducible measure, which shows a high specificity for Marfan syndrome and Loeys-Dietz syndrome and may be useful in differentiating these 2 entities.
Assuntos
Artérias/patologia , Encéfalo/patologia , Síndrome de Loeys-Dietz/diagnóstico por imagem , Síndrome de Loeys-Dietz/patologia , Síndrome de Marfan/diagnóstico por imagem , Síndrome de Marfan/patologia , Adulto , Artérias/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Angiografia Cerebral/métodos , Diagnóstico Diferencial , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Angiografia por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto JovemRESUMO
The term inflammaging is now widely used to designate the inflammatory process of natural aging. During this process, cytokine balance is altered, presumably due to the loss of homeostasis, thus contributing to a greater predisposition to disease and exacerbation of chronic diseases. The aim of the study was to analyze the relationship between pro-inflammatory markers and age in the natural aging process of healthy individuals. One hundred and ten subjects were divided into 5 groups according to age (22 subjects/group). Interleukin-6 (IL-6) and tumor necrosis factor α (TNF-α) were quantified using the ELISA method. High-sensitivity C-reactive protein (hsCRP) was analyzed by turbidimetry according to laboratory procedures. The main findings of this study were: a positive correlation between hsCRP and IL-6 as a function of age (110 subjects); women showed stronger correlations; the 51-60 age group had the highest values for hsCRP and IL-6; women presented higher values for hsCRP in the 51-60 age group and higher values for IL-6 in the 61-70 age group; and men showed higher values in the 51-60 age group for hsCRP and IL-6. In conclusion, the natural aging process increased IL-6 and hsCRP levels, which is consistent with the inflammaging theory; however, women presented stronger correlations compared to men (IL-6 and hsCRP) and the 51-60 age range seems to be a key point for these increases. These findings are important because they indicate that early preventive measures may minimize the increase in these inflammatory markers in natural human aging.
Assuntos
Envelhecimento/fisiologia , Imunossenescência/fisiologia , Inflamação/sangue , Adulto , Fatores Etários , Idoso , Biomarcadores/análise , Proteína C-Reativa/análise , Colesterol/sangue , Feminino , Humanos , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Fatores Sexuais , Triglicerídeos/sangue , Fator de Necrose Tumoral alfa/sangue , Adulto JovemRESUMO
The term inflammaging is now widely used to designate the inflammatory process of natural aging. During this process, cytokine balance is altered, presumably due to the loss of homeostasis, thus contributing to a greater predisposition to disease and exacerbation of chronic diseases. The aim of the study was to analyze the relationship between pro-inflammatory markers and age in the natural aging process of healthy individuals. One hundred and ten subjects were divided into 5 groups according to age (22 subjects/group). Interleukin-6 (IL-6) and tumor necrosis factor α (TNF-α) were quantified using the ELISA method. High-sensitivity C-reactive protein (hsCRP) was analyzed by turbidimetry according to laboratory procedures. The main findings of this study were: a positive correlation between hsCRP and IL-6 as a function of age (110 subjects); women showed stronger correlations; the 51-60 age group had the highest values for hsCRP and IL-6; women presented higher values for hsCRP in the 51-60 age group and higher values for IL-6 in the 61-70 age group; and men showed higher values in the 51-60 age group for hsCRP and IL-6. In conclusion, the natural aging process increased IL-6 and hsCRP levels, which is consistent with the inflammaging theory; however, women presented stronger correlations compared to men (IL-6 and hsCRP) and the 51-60 age range seems to be a key point for these increases. These findings are important because they indicate that early preventive measures may minimize the increase in these inflammatory markers in natural human aging.
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Envelhecimento/fisiologia , Imunossenescência/fisiologia , Inflamação/sangue , Consumo de Oxigênio/fisiologia , Triglicerídeos/sangue , Proteína C-Reativa/análise , Biomarcadores/análise , Fatores Sexuais , Colesterol/sangue , Fatores Etários , Interleucina-6/sangue , Fator de Necrose Tumoral alfa/sangueRESUMO
Vaccines play an essential role in keeping humans healthy. Innovative approaches to their use include the utilization of plasmid DNA encoding sequences to express foreign antigens. DNAhsp65 from Mycobacterium leprae is suitable for this purpose due to its ability to elicit a powerful immune response. Controlled release systems represent a promising approach to delivering vaccines. In this work, we used liposomes or PLGA systems to deliver DNAhsp65 to treat the pulmonary fungal infection Paracoccidioidomycosis. Both formulations modulated a protective immune response and reduced the pulmonary fungal burden even in the groups receiving less than four times the amount of the DNAhps65 entrapped within the nanoparticles. Although both systems had the same effective therapeutic results, the advantage of the liposome formulation was that it was administered intranasally, which may be more easily accepted by patients. These systems are a great alternative to be considered as adjuvant vaccine therapy for systemic mycosis.
Assuntos
Biotecnologia/métodos , Vacinas Fúngicas/administração & dosagem , Técnicas de Transferência de Genes , Nanotecnologia/métodos , Paracoccidioidomicose/imunologia , Paracoccidioidomicose/prevenção & controle , Vacinas de DNA/administração & dosagem , Animais , Proteínas de Bactérias/metabolismo , Proliferação de Células , Chaperonina 60/metabolismo , Citocinas/metabolismo , Vacinas Fúngicas/imunologia , Imunidade Humoral/imunologia , Imunoglobulina G/sangue , Ácido Láctico/química , Lipossomos/química , Pulmão/imunologia , Pulmão/microbiologia , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium leprae/metabolismo , Óxido Nítrico/metabolismo , Paracoccidioides/fisiologia , Paracoccidioidomicose/sangue , Paracoccidioidomicose/microbiologia , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Baço/metabolismo , Vacinas de DNA/imunologiaRESUMO
Prostaglandins (PGs) and leukotrienes (LTs) are produced in Mycobacterium tuberculosis (Mtb)-infected lungs and have immune suppressive and protective effects, respectively. Considering that both of these mediators are produced during mycobacterial infection, we investigated the specific and relative biological importance of each in regulating host response in experimental tuberculosis. Administration of celecoxib, which was found to reduce lung levels of PGE(2) and increase LTB(4), enhanced the 60-day survival of Mtb-infected mice in 14%. However administration of MK-886, which reduced levels of LTB(4) but did not enhance PGE(2), reduced 60-day survival from 86% to 43% in Mtb-infected mice, and increased lung bacterial burden. MK-886 plus celecoxib reduced survival to a lesser extent than MK-886 alone. MK-886- and MK-886 plus celecoxib-treated animals exhibited reduced levels of the protective interleukin-12 and gamma-interferon. Our findings indicate that in this model, the protective effect of LTs dominates over the suppressive effect of PGs.
Assuntos
Adjuvantes Imunológicos/farmacologia , Imunossupressores/farmacologia , Leucotrienos/farmacologia , Pulmão/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Prostaglandinas/farmacologia , Animais , Líquido da Lavagem Broncoalveolar/imunologia , Líquido da Lavagem Broncoalveolar/microbiologia , Citocinas/imunologia , Citocinas/metabolismo , Indóis/farmacologia , Leucotrienos/imunologia , Inibidores de Lipoxigenase/farmacologia , Pulmão/imunologia , Pulmão/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium tuberculosis/crescimento & desenvolvimento , Mycobacterium tuberculosis/imunologia , Óxido Nítrico/imunologia , Óxido Nítrico/metabolismo , Prostaglandinas/imunologia , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/patologia , Tuberculose Pulmonar/prevenção & controleRESUMO
It is well known that eosinophilia is a key pathogenetic component of toxocariasis. The objective of the present study was to determine if there is an association between peritoneal and blood eosinophil influx, mast cell hyperplasia and leukotriene B(4) (LTB(4)) production after Toxocara canis infection. Oral inoculation of 56-day-old Wistar rats (N = 5-7 per group) with 1000 embryonated eggs containing third-stage (L3) T. canis larvae led to a robust accumulation of total leukocytes in blood beginning on day 3 and peaking on day 18, mainly characterized by eosinophils and accompanied by higher serum LTB(4) levels. At that time, we also noted increased eosinophil numbers in the peritoneal cavity. In addition, we observed increased peritoneal mast cell number in the peritoneal cavity, which correlated with the time course of eosinophilia during toxocariasis. We also demonstrated that mast cell hyperplasia in the intestines and lungs began soon after the T. canis larvae migrated to these compartments, reaching maximal levels on day 24, which correlated with the complete elimination of the parasite. Therefore, mast cells appear to be involved in peritoneal and blood eosinophil infiltration through an LTB(4)-dependent mechanism following T. canis infection in rats. Our data also demonstrate a tight association between larval migratory stages and intestinal and pulmonary mast cell hyperplasia in the toxocariasis model.
Assuntos
Eosinofilia/parasitologia , Leucotrieno B4/biossíntese , Pulmão/parasitologia , Mastócitos/parasitologia , Toxocara canis , Toxocaríase/parasitologia , Animais , Eosinofilia/imunologia , Hiperplasia/parasitologia , Hiperplasia/patologia , Intestinos/parasitologia , Intestinos/patologia , Pulmão/patologia , Masculino , Mastócitos/patologia , Cavidade Peritoneal , Ratos , Ratos Wistar , Toxocaríase/imunologia , Toxocaríase/patologiaRESUMO
It is well known that eosinophilia is a key pathogenetic component of toxocariasis. The objective of the present study was to determine if there is an association between peritoneal and blood eosinophil influx, mast cell hyperplasia and leukotriene B4 (LTB4) production after Toxocara canis infection. Oral inoculation of 56-day-old Wistar rats (N = 5-7 per group) with 1000 embryonated eggs containing third-stage (L3) T. canis larvae led to a robust accumulation of total leukocytes in blood beginning on day 3 and peaking on day 18, mainly characterized by eosinophils and accompanied by higher serum LTB4 levels. At that time, we also noted increased eosinophil numbers in the peritoneal cavity. In addition, we observed increased peritoneal mast cell number in the peritoneal cavity, which correlated with the time course of eosinophilia during toxocariasis. We also demonstrated that mast cell hyperplasia in the intestines and lungs began soon after the T. canis larvae migrated to these compartments, reaching maximal levels on day 24, which correlated with the complete elimination of the parasite. Therefore, mast cells appear to be involved in peritoneal and blood eosinophil infiltration through an LTB4-dependent mechanism following T. canis infection in rats. Our data also demonstrate a tight association between larval migratory stages and intestinal and pulmonary mast cell hyperplasia in the toxocariasis model.
Assuntos
Animais , Masculino , Ratos , Eosinofilia/parasitologia , /biossíntese , Pulmão/parasitologia , Mastócitos/parasitologia , Toxocara canis , Toxocaríase/parasitologia , Eosinofilia/imunologia , Hiperplasia/parasitologia , Hiperplasia/patologia , Intestinos/parasitologia , Intestinos/patologia , Pulmão/patologia , Mastócitos/patologia , Cavidade Peritoneal , Ratos Wistar , Toxocaríase/imunologia , Toxocaríase/patologiaRESUMO
Leukotrienes are reported to be potent proinflammatory mediators that play a role in the development of several inflammatory diseases such as asthma, rheumatoid arthritis and periodontal disease. Leukotrienes have also been associated with protection against infectious diseases. However, the role of leukotrienes in Mycobacterium tuberculosis infection is not understood. To answer this question, we studied the role of leukotrienes in the protective immune response conferred by prime-boost heterologous immunization against tuberculosis. We immunized BALB/c mice (4-11/group) with subcutaneous BCG vaccine (1 x 10(5) M. bovis BCG) (prime) followed by intramuscular DNA-HSP65 vaccine (100 µg) (boost). During the 30 days following the challenge, the animals were treated by gavage daily with MK-886 (5 mg·kg-1·day-1) to inhibit leukotriene synthesis. We showed that MK-886-treated mice were more susceptible to M. tuberculosis infection by counting the number of M. tuberculosis colony-forming units in lungs. The histopathological analysis showed an impaired influx of leukocytes to the lungs of MK-886-treated mice after infection, confirming the involvement of leukotrienes in the protective immune response against experimental tuberculosis. However, prime-boost-immunized mice treated with MK-886 remained protected after challenge with M. tuberculosis, suggesting that leukotrienes are not required for the protective effect elicited by immunization. Protection against M. tuberculosis challenge achieved by prime-boost immunization in the absence of leukotrienes was accompanied by an increase in IL-17 production in the lungs of these animals, as measured by ELISA. Therefore, these data suggest that the production of IL-17 in MK-886-treated, immunized mice could contribute to the generation of a protective immune response after infection with M. tuberculosis.
Assuntos
Animais , Feminino , Camundongos , Proteínas de Bactérias/imunologia , /imunologia , Leucócitos/imunologia , Leucotrienos/biossíntese , Tuberculose Pulmonar/prevenção & controle , Vacinas de DNA/imunologia , Vacina BCG/administração & dosagem , Vacina BCG/imunologia , Proteínas de Bactérias/administração & dosagem , Movimento Celular , /administração & dosagem , Citocinas/biossíntese , Imunização Secundária , Indóis/farmacologia , Antagonistas de Leucotrienos/farmacologia , Leucotrienos/agonistas , Pulmão/imunologia , Pulmão/microbiologia , Pulmão/patologia , Camundongos Endogâmicos BALB C , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/patologia , Vacinas de DNA/administração & dosagemRESUMO
Leukotrienes are reported to be potent proinflammatory mediators that play a role in the development of several inflammatory diseases such as asthma, rheumatoid arthritis and periodontal disease. Leukotrienes have also been associated with protection against infectious diseases. However, the role of leukotrienes in Mycobacterium tuberculosis infection is not understood. To answer this question, we studied the role of leukotrienes in the protective immune response conferred by prime-boost heterologous immunization against tuberculosis. We immunized BALB/c mice (4-11/group) with subcutaneous BCG vaccine (1 x 10(5) M. bovis BCG) (prime) followed by intramuscular DNA-HSP65 vaccine (100 microg) (boost). During the 30 days following the challenge, the animals were treated by gavage daily with MK-886 (5 mg x kg(-1) x day(-1)) to inhibit leukotriene synthesis. We showed that MK-886-treated mice were more susceptible to M. tuberculosis infection by counting the number of M. tuberculosis colony-forming units in lungs. The histopathological analysis showed an impaired influx of leukocytes to the lungs of MK-886-treated mice after infection, confirming the involvement of leukotrienes in the protective immune response against experimental tuberculosis. However, prime-boost-immunized mice treated with MK-886 remained protected after challenge with M. tuberculosis, suggesting that leukotrienes are not required for the protective effect elicited by immunization. Protection against M. tuberculosis challenge achieved by prime-boost immunization in the absence of leukotrienes was accompanied by an increase in IL-17 production in the lungs of these animals, as measured by ELISA. Therefore, these data suggest that the production of IL-17 in MK-886-treated, immunized mice could contribute to the generation of a protective immune response after infection with M. tuberculosis.
Assuntos
Proteínas de Bactérias/imunologia , Chaperonina 60/imunologia , Leucócitos/imunologia , Leucotrienos/biossíntese , Tuberculose Pulmonar/prevenção & controle , Vacinas de DNA/imunologia , Animais , Vacina BCG/administração & dosagem , Vacina BCG/imunologia , Proteínas de Bactérias/administração & dosagem , Movimento Celular , Chaperonina 60/administração & dosagem , Citocinas/biossíntese , Feminino , Imunização Secundária , Indóis/farmacologia , Antagonistas de Leucotrienos/farmacologia , Leucotrienos/agonistas , Pulmão/imunologia , Pulmão/microbiologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/patologia , Vacinas de DNA/administração & dosagemRESUMO
With the evidence showing the protection variability of bacille Calmette-Guérin, new potential vaccines for tuberculosis have been tested around the world. One of the general concerns in tuberculosis vaccine development is the possibility of priming the host immune system with prior exposure to environmental mycobacteria antigens, which can change the efficacy of subsequent vaccination. As there is a great homology between the species from Mycobacterium genera, the previous contact of experimental animals with environmental mycobacteria could sensitize the mice and, in this way, could influence subsequent vaccine research. The aim of our study was to investigate critical points in an animal facility to search for environmental mycobacteria that eventually could be in direct or indirect contact with the experimental animals. Samples were collected from surfaces of walls, floor, animal cages and shelves and analysed using the Ogawa-Kudoh decontamination method. Samples of drinking water, food and sawdust were collected for analysis by the NALC/NaOH decontamination method. Also, the samples were cultivated directly in broth medium, without any method for decontamination. After decontamination methods, we observed bacterial colony growth in 4.31% of the total of samples analysed. These samples were stained with Ziehl-Neelsen and we did not detect any acid-fast bacilli, suggesting that the animal facility analysed is free from contamination by environmental mycobacteria and is not a source of mycobacterial antigens. Furthermore, our study showed a new paradigm in tuberculosis vaccine development: concern about the animal facility environment in terms of immune system priming of experimental animals by nascent bacterial contaminants.
Assuntos
Descontaminação/métodos , Exposição Ambiental/análise , Infecções por Mycobacterium/microbiologia , Mycobacterium/isolamento & purificação , Acetilcisteína , Animais , Antígenos de Bactérias , Vacina BCG/imunologia , Incrustação Biológica , Brasil , Abrigo para Animais , Camundongos , Mycobacterium/imunologia , Infecções por Mycobacterium/imunologia , Hidróxido de Sódio , Organismos Livres de Patógenos Específicos , Tuberculose/imunologia , Tuberculose/prevenção & controleRESUMO
The course and outcome of infection with mycobacteria are determined by a complex interplay between the immune system of the host and the survival mechanisms developed by the bacilli. Recent data suggest a regulatory role of histamine not only in the innate but also in the adaptive immune response. We used a model of pulmonary Mycobacterium tuberculosis infection in histamine-deficient mice lacking histidine decarboxylase (HDC(-/-)), the histamine-synthesizing enzyme. To confirm that mycobacterial infection induced histamine production, we exposed mice to M. tuberculosis and compared responses in C57BL/6 (wild-type) and HDC(-/-) mice. Histamine levels increased around fivefold above baseline in infected C57BL/6 mice at day 28 of infection, whereas only small amounts were detected in the lungs of infected HDC(-/-) mice. Blocking histamine production decreased both neutrophil influx into lung tissue and the release of proinflammatory mediators, such as interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-alpha), in the acute phase of infection. However, the accumulation and activation of CD4(+) T cells were augmented in the lungs of infected HDC(-/-) mice and correlated with a distinct granuloma formation that contained abundant lymphocytic infiltration and reduced numbers of mycobacteria 28 days after infection. Furthermore, the production of IL-12, gamma interferon, and nitric oxide, as well as CD11c(+) cell influx into the lungs of infected HDC(-/-) mice, was increased. These findings indicate that histamine produced after M. tuberculosis infection may play a regulatory role not only by enhancing the pulmonary neutrophilia and production of IL-6 and TNF-alpha but also by impairing the protective Th1 response, which ultimately restricts mycobacterial growth.
Assuntos
Histamina/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/patologia , Animais , Linfócitos T CD4-Positivos/imunologia , Citocinas/metabolismo , Granuloma/microbiologia , Granuloma/patologia , Histidina Descarboxilase/deficiência , Pulmão/imunologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/imunologia , Óxido Nítrico/metabolismoRESUMO
AIM: To evaluate in vitro the effect of calcium hydroxide [Ca(OH)(2)] and Er:YAG laser on bacterial endotoxin [also known as lipopolysaccharide (LPS)] as determined by nitric oxide (NO) detection in J774 murine macrophage cell line culture. METHODOLOGY: Samples of LPS solution (50 microg mL(-1)), Ca(OH)(2) suspension (25 mg mL(-1)) and LPS suspension with Ca(OH)(2) were prepared. The studied groups were: I - LPS (control); II - LPS + Ca(OH)(2); III - LPS + Er:YAG laser (15 Hz 140 mJ); IV - LPS + Er:YAG laser (15 Hz 200 mJ); V - LPS + Er:YAG laser (15 Hz 250 mJ), VI - Pyrogen-free water; VII - Ca(OH)(2). Murine macrophage J774 cells were plated and 10 microL of the samples were added to each well. The supernatants were collected for NO detection by the Griess reaction. Data were analysed statistically by one-way anova and Tukey's test at 5% significance level. RESULTS: The mean and SE (in micromol L(-1)) values of NO release were: I - 10.48 +/- 0.58, II - 6.41 +/- 0.90, III - 10.2 +/- 0.60, IV - 8.35 +/- 0.40, V - 10.40 +/- 0.53, VI - 3.75 +/- 0.70, VII - 6.44 +/- 0.60; and the values for the same experiment repeated after 1 week were: I - 21.20 +/- 1.50, II - 9.10 +/- 0.60, III - 19.50 +/- 1.00, IV - 18.50 +/- 0.60, V - 21.30 +/- 0.90, VI - 2.00+/- 0.20, VII - 6.80 +/- 1.70. There was no significant difference (P > 0.05) between the control and the laser-treated groups (III, IV and V), or comparing groups II, VI and VII to each other (P > 0.05). Group I had significantly higher NO release than group II (P < 0.05). Groups II and VI had similar NO release (P > 0.05). CONCLUSIONS: Calcium hydroxide inactivated the bacterial endotoxin (LPS) whereas none of the Er:YAG laser parameter settings had the same effectiveness.
Assuntos
Hidróxido de Cálcio/farmacologia , Lasers de Estado Sólido , Lipopolissacarídeos/antagonistas & inibidores , Macrófagos/metabolismo , Óxido Nítrico/biossíntese , Irrigantes do Canal Radicular/farmacologia , Animais , Linhagem Celular , Escherichia coli/química , Macrófagos/efeitos dos fármacos , Camundongos , Óxido Nítrico/análiseRESUMO
Recent studies revealed that vasopressinergic neurons have a high content of cys-leukotriene C(4) (LTC(4)) synthase, a critical enzyme in cys-leukotriene synthesis that may play a role in regulating vasopressin secretion. This study investigates the role of this enzyme in arginine vasopressin (AVP) release during experimentally induced sepsis. Male Wistar rats received an i.c.v. injection of 3-[1-(p-chlorobenzyl)-5-(isopropyl)-3-tert-butylthioindol-2-yl]-2, 2-dimethylpropanoic acid (MK-886) (1.0 microg/kg), a leukotrienes (LTs) synthesis inhibitor, or vehicle, 1 h before cecal ligation and puncture (CLP) or sham operation. In one group of animals the survival rate was monitored for 3 days. In another group, the animals were decapitated at 0, 4, 6, 18 and 24 h after CLP or sham operation, and blood was collected for hematocrit, serum sodium and nitrate, plasma osmolality, protein and AVP determination. A third group was used for blood pressure measurements. The neurohypophysis was removed for quantification of AVP content, and the hypothalamus was dissected for LTC(4) synthase analysis by Western blot. Mortality after CLP was reduced by the central administration of MK-886. The increase in plasma AVP levels and hypothalamus LTC(4) synthase content in the initial phase of sepsis was blocked, whereas the decrease in neurohypophyseal AVP content was partially reversed. Also the blood pressure drop was abolished in this phase. The increase of serum nitric oxide and hematocrit was reduced, and the decrease in plasma protein and osmolality was not affected by the LTs blocker. In the final phase of sepsis, the plasma AVP level and the hypothalamic LTC(4) synthase content were at basal levels. The central administration of MK-886 increased the hypothalamic LTC(4) synthase content but did not alter the plasma and neurohypophysis AVP levels observed, or the blood pressure during this phase. These results suggest that the central LTs are involved in the vasopressin release observed during sepsis.
Assuntos
Arginina Vasopressina/metabolismo , Glutationa Transferase/antagonistas & inibidores , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Leucotrienos/biossíntese , Sepse/enzimologia , Animais , Arginina Vasopressina/sangue , Modelos Animais de Doenças , Glutationa Transferase/metabolismo , Hematócrito , Hipotensão/tratamento farmacológico , Hipotensão/enzimologia , Hipotensão/fisiopatologia , Indóis/farmacologia , Leucotrieno C4/biossíntese , Inibidores de Lipoxigenase/farmacologia , Masculino , Óxido Nítrico/sangue , Neuro-Hipófise/efeitos dos fármacos , Neuro-Hipófise/metabolismo , Ratos , Ratos Wistar , Sepse/fisiopatologiaRESUMO
OBJECTIVE: Suramin is a polysulphonated napthylurea antiprotozoal and anthelminitic drug, which also presents inhibitory activity against a broad range of enzymes. Here we evaluate the effect of suramin on the hydrolytic and biological activities of secreted human group IIA phospholipase A(2) (hsPLA(2)GIIA). MATERIALS AND METHODS: The hsPLA(2)GIIA was expressed in E. coli, and refolded from inclusion bodies. The hydrolytic activity of the recombinant enzyme was measured using mixed dioleoylphosphatidylcholine/dioleoylphosphatidylglycerol (DOPC/DOPG) liposomes. The activation of macrophage cell line RAW 264.7 by hsPLA(2) GIIA was monitored by NO release, and bactericidal activity against Micrococcus luteus was evaluated by colony counting and by flow cytometry using the fluorescent probe Sytox Green. RESULTS: The hydrolytic activity of the hsPLA(2) GIIA was inhibited by a concentration of 100 nM suramin and the activation of macrophages by hsPLA(2) GIIA was abolished at protein/suramin molar ratios where the hydrolytic activity of the enzyme was inhibited. In contrast, both the bactericidal activity of hsPLA(2) GIIA against Micrococcus luteus and permeabilization of the bacterial inner membrane were unaffected by suramin concentrations up to 50 microM. CONCLUSIONS: These results demonstrate that suramin selectively inhibits the activity of the hsPLA(2) GIIA against macrophages, whilst leaving the anti-bacterial function unchanged.
Assuntos
Antinematódeos/farmacologia , Fosfolipases A2 do Grupo II/metabolismo , Ativação de Macrófagos/efeitos dos fármacos , Suramina/farmacologia , Animais , Antinematódeos/química , Linhagem Celular , Fosfolipases A2 do Grupo II/química , Fosfolipases A2 do Grupo II/genética , Humanos , Corpos de Inclusão/enzimologia , Ativação de Macrófagos/fisiologia , Macrófagos/citologia , Macrófagos/fisiologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Suramina/químicaRESUMO
We previously reported the anti-inflammatory activity of Lafoensia pacari extract in Toxocara canis infection, a model of systemic IL-5-dependent eosinophil migration. In the present study, we describe the kinetics of the anti-inflammatory activity of L. pacari extract and compare it with dexamethasone. T. canis-infected mice were submitted to different treatment protocols and the cells present in bronchoalveolar space and peritoneal cavity were collected at the end of each treatment period. The results showed that L. pacari extract effectively inhibited eosinophil migration only when the treatment was initiated before the peak of eosinophil migration (1st to 18th; 12th to 18th and 12th to 24th day post-infection). When eosinophil migration was established, administration of L. pacari extract had no effect on it (treatment 18th to 24th day post-infection). Dexamethasone was effective in inhibiting eosinophil migration in all periods studied. We suggest that L. pacari extract can potentially be a natural alternative treatment of eosinophilic diseases.
Assuntos
Eosinófilos/efeitos dos fármacos , Lythraceae/química , Fitoterapia , Extratos Vegetais/uso terapêutico , Toxocaríase/tratamento farmacológico , Animais , Líquido da Lavagem Broncoalveolar/citologia , Movimento Celular/efeitos dos fármacos , Dexametasona/farmacocinética , Dexametasona/farmacologia , Dexametasona/uso terapêutico , Eosinófilos/fisiologia , Feminino , Fígado/patologia , Camundongos , Cavidade Peritoneal/citologia , Casca de Planta/química , Extratos Vegetais/química , Extratos Vegetais/farmacocinética , Distribuição Aleatória , Toxocaríase/patologiaRESUMO
OBJECTIVE: Eosinophils and cytokines are implicated in the pathogenesis of allergic diseases. In the present study, we investigate the anti-inflammatory effect of quercetin and isoquercitrin in a murine model of asthma. METHODS: BALB/c mice were immunized (ovalbumin/aluminum hydroxide, s. c.), followed by two intranasal ovalbumin challenges. From day 18 to day 22 after the first immunization, the mice received daily gavages of isoquercitrin (15 mg/kg) or quercetin (10 mg/kg). Dexamethasone (1 mg/kg, s. c.) was administered as a positive control. Leucocytes were analyzed in bronchoalveolar lavage fluid (BALF), blood and pulmonary parenchyma at 24 h after the last ovalbumin challenge. Interleukin-5 (IL-5) was analyzed in BALF and lung homogenates. RESULTS: In animals receiving isoquercitrin or quercetin, eosinophil counts were lower in the BALF, blood and lung parenchyma. Neutrophil counts in blood and IL-5 levels in lung homogenate were lower only in isoquercitrin-treated mice. No alterations in mononuclear cell numbers were observed. CONCLUSION: Quercetin and isoquercitrin are effective eosinophilic inflammation suppressors, suggesting a potential for treating allergies.
Assuntos
Anti-Inflamatórios/uso terapêutico , Asma/tratamento farmacológico , Quercetina/análogos & derivados , Quercetina/uso terapêutico , Animais , Asma/imunologia , Líquido da Lavagem Broncoalveolar/imunologia , Contagem de Células , Feminino , Interferon gama/análise , Interleucina-5/análise , Pulmão/imunologia , Camundongos , Camundongos Endogâmicos BALB CRESUMO
In human hosts and in murine models, the immune response to Strongyloides spp. is Th2 type. In addition, the profile of the host immune response follows various symptoms induced by Strongyloides spp. In the present study, we demonstrated that the L2 and L49 strains of Strongyloides venezuelensis obtained from Bolomys lasiurus and Nectomys squamipes induced significant and similar increases in eosinophil/mononuclear cell counts in the blood, peritoneal cavity fluid and bronchoalveolar lavage fluid when compared with uninfected mice. However, in the first 3 days of infection, IL-4, IL-5 and IFN-gamma levels were higher in the lungs of mice infected with the L2 strain, which also presented greater production of IgG and IgG1 than did mice infected with the L49 strain. The higher antibody and cytokine levels induced by the L2 strain correlated with a decrease in the number of female parasites recovered in the faeces of mice on post-infection day 7. The results demonstrate that the L2 strain was a more potent stimulant of the humoral immune response, which can result in more efficient antibody-dependent cell-mediated cytotoxicity, a mechanism involved in eosinophil activation and parasite elimination. Further studies are needed in order to elucidate the molecular differences among parasites.
Assuntos
Strongyloides/imunologia , Estrongiloidíase/imunologia , Animais , Líquido da Lavagem Broncoalveolar/imunologia , Citocinas/imunologia , Eosinófilos/imunologia , Interferon gama/imunologia , Larva/imunologia , Pulmão/imunologia , Pulmão/parasitologia , Masculino , Camundongos , Contagem de Ovos de Parasitas , Ratos , Ratos Wistar , Roedores , Strongyloides/classificação , Strongyloides/crescimento & desenvolvimento , Strongyloides/isolamento & purificação , Estrongiloidíase/sangue , Estrongiloidíase/parasitologia , Zoonoses/parasitologiaRESUMO
Although insects lack the adaptive immune response of the mammalians, they manifest effective innate immune responses, which include both cellular and humoral components. Cellular responses are mediated by hemocytes, and humoral responses include the activation of proteolytic cascades that initiate many events, including NO production. In mammals, nitric oxide synthases (NOSs) are also present in the endothelium, the brain, the adrenal glands, and the platelets. Studies on the distribution of NO-producing systems in invertebrates have revealed functional similarities between NOS in this group and vertebrates. We attempted to localize NOS activity in tissues of naïve (UIL), yeast-injected (YIL), and saline-injected (SIL) larvae of the blowfly Chrysomya megacephala, using the NADPH diaphorase technique. Our findings revealed similar levels of NOS activity in muscle, fat body, Malpighian tubule, gut, and brain, suggesting that NO synthesis may not be involved in the immune response of these larval systems. These results were compared to many studies that recorded the involvement of NO in various physiological functions of insects.