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1.
Ecol Appl ; 29(3): e01857, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30680837

RESUMO

Worldwide, stocking of fish represents a valuable tool for conservation and maintenance of species exploited by recreational fishing. Releases of hatchery-reared fish are more and more recognized to have numerous demographic, ecological, and genetic impacts on wild populations. However, consequences on intraspecific trophic relationships have rarely been investigated. In this study, we assessed the impacts of supplementation stocking and resulting introgressive hybridization on the trophic niches occupied by stocked, local, and hybrid lake trout (Salvelinus namaycush) within populations of piscivorous and planktivorous ecotypes stocked from a wild piscivorous source population. We compared trophic niches using stable isotope analysis (δ13 C and δ15 N) and trophic position among the three genetic origins. Putative genetic effects were tested with phenotype-genotype association of "life history" ecological traits (body size, growth rate, condition index, and trophic niche) and genotypes (RADseq SNP markers) using redundant discriminant analysis (RDA). Results showed that sympatry resulting from the stocking of contrasting ecotypes is a risk factor for niche partitioning. Planktivorous populations are more susceptible to niche partitioning, by competitive exclusion of the local fish from a littoral niche to an alternative pelagic/profundal niche. Observed niche partitioning is probably a manifestation of competitive interactions between ecotypes. Our results emphasize that ecotypic variation should be considered for more efficient management and conservation practices and in order to mitigate negative impact of supplementation stocking.


Assuntos
Ecótipo , Interação Gene-Ambiente , Animais , Ecologia , Genótipo , Truta
2.
Mol Ecol ; 25(19): 4773-92, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27497114

RESUMO

Repeated adaptive ecological diversification has commonly been reported in fish and has often been associated with trophic niche diversity. The main goal of this study was to investigate the extent of parallelism in the genomic and phenotypic divergence between piscivorous and planktivorous lake trout ecotypes from Laurentian Shield lakes, Canada. This was achieved by documenting the extent of morphological differentiation using geometric morphometrics and linear measurements as well as the pattern of genomic divergence by means of RADseq genotyping (3925 filtered SNPs) in 12 lakes. Our results indicate that the two ecotypes evolved distinct body shape and several linear measurements in parallel. Neutral genetic differentiation was pronounced between all isolated populations (Mean FST  = 0.433), indicating no or very limited migration and pronounced genetic drift. Significant genetic differentiation also suggested partial reproductive isolation between ecotypes in the two lakes where they are found in sympatry. Combining different outlier detection methods, we identified 48 SNPs putatively under divergent selection between ecotypes, among which 10 could be annotated and related to functions such as developmental processes and ionic regulation. Finally, our results indicate that parallel morphological divergence is accompanied by both parallel and nonparallel genomic divergence, which is associated with the use of different trophic niches between ecotypes. The results are also discussed in the context of management and conservation of this highly exploited species throughout northern North America.


Assuntos
Ecótipo , Genética Populacional , Seleção Genética , Truta/genética , Animais , Canadá , Genômica , Genótipo , Lagos , Fenótipo , Polimorfismo de Nucleotídeo Único , Isolamento Reprodutivo , Análise de Sequência de DNA , Simpatria
3.
Osteoporos Int ; 23(10): 2403-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22525981

RESUMO

Osteoporosis has until now been considered to be a disease associated with abnormal calcium metabolism. However, an increasing number of clinical observations strongly suggest the association of iron overload with bone diseases, particularly in osteoporosis in menopausal women. The recent identification of hepcidin sheds new light into the crucial role of iron homeostasis in bone metabolism. Decreasing iron overload in cell studies as well as in animal experiments has been shown to improve bone cell metabolism and growth in vitro and in vivo. In view of the significant iron overload found in the aging population, especially in females, the therapeutic potential of lowering iron overload for the treatment of osteoporosis is suggested.


Assuntos
Sobrecarga de Ferro/complicações , Osteoporose/etiologia , Animais , Peptídeos Catiônicos Antimicrobianos/fisiologia , Feminino , Hepcidinas , Homeostase/fisiologia , Humanos , Ferro/metabolismo , Osteoporose/fisiopatologia
4.
Peptides ; 31(10): 1884-7, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20603171

RESUMO

The effects of lipopolysaccharide (LPS) and desArg9Bradykinin (DBK) on the release of nitric oxide (NO) from macrophages of mice 8, 12 and 18 days after having been treated with low doses of streptozotocin (STZ; 5 × 45 mg/kg) were studied. The results showed that LPS stimulated the release of NO from macrophages of untreated animals by 50% whereas the bradykinin B(1) agonist desArg9Bradykinin (DBK) increased the level of NO by 20%. This increased NO production was totally abolished by incubating the cells with R-954, a selective bradykinin B(1) antagonist. The release of NO from macrophages of STZ-treated mice incubated in the presence of LPS was more marked and reached approximately 220, 300 and 270% respectively from cells collected 8, 12 and 18 days after the STZ treatment. These significant increases were completely blocked by R-954 and were even below control values. Similarly the results showed that DBK stimulated by 50-75% the release of NO from macrophages of STZ-treated mice. The most marked stimulation was noted when the cells were collected 18 days after the treatment of the animals with STZ. Again in this set of experiments the B(1) antagonist completely blocked the release of NO which went even below control values. The results clearly suggest the upregulation of bradykinin B(1) receptors in mouse macrophages in the early phase of STZ-induced diabetes, an event that could even precede the onset of the diabetic hyperglycemia.


Assuntos
Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Tipo 1/imunologia , Ativação de Macrófagos/imunologia , Macrófagos Peritoneais/imunologia , Animais , Glicemia/efeitos dos fármacos , Bradicinina/química , Bradicinina/farmacologia , Células Cultivadas , Lipopolissacarídeos/farmacologia , Macrófagos Peritoneais/citologia , Macrófagos Peritoneais/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico/imunologia , Óxido Nítrico/metabolismo , Receptor B1 da Bradicinina/metabolismo , Estreptozocina/imunologia , Estreptozocina/farmacologia
5.
Biotechnol Adv ; 26(5): 389-97, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18565715

RESUMO

HIV infection is one of the major threats to human health due to the lack of relevant vaccine and drugs to cure AIDS. Its early diagnosis is thus important in controlling HIV transmission. Molecular diagnosis of HIV can be performed qualitatively and quantitatively. Currently, molecular diagnosis of HIV infection is only used as a complementary diagnosis although viral load test is used to monitor disease progression and responsiveness to antiviral therapy. To optimize HIV assays, a variety of technological advances, such as the introduction of dUTP/UNG system, real-time detection platform, and coupling of more than one enzyme in molecular identification, have been integrated into new methods. With the development of more reliable HIV assays in the future, the molecular diagnosis of HIV is expected to be accepted as one of the standards in determining whether there is a HIV infection in resource-rich laboratories, which will play a crucial role in reducing HIV transmission.


Assuntos
Biotecnologia/tendências , Análise Mutacional de DNA/tendências , DNA Viral/genética , Infecções por HIV/diagnóstico , Infecções por HIV/virologia , Técnicas de Sonda Molecular , Humanos
6.
Mol Biotechnol ; 37(3): 225-36, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17952669

RESUMO

RNA interference is not only very promising in identifying new targets for drug development, siRNA/shRNA themselves may be directly used as therapeutic agents. In inhibiting viral infections by RNA interference, both viral targets and cellular proteins have been evaluated. Most of the early studies in this field had chosen viral targets for RNA interference. However, recent efforts are mainly focusing on cellular proteins for RNA silencing due to the realization that a variety of viral responses substantially minimize siRNA effects. With the application of siRNA approaching, many new cellular targets relevant to HIV infection have been identified. The value of siRNA/shRNA in the treatment of AIDS is largely dependent on better understanding of the biology of HIV replication. Efforts in the identification of cellular processes with the employment of siRNA/shRNA have shed some new lights on our understanding of how HIV infection occurs. Furthermore, the relative specific effects and simplicity of design makes siRNA/shRNA themselves to be favorable drug leads.


Assuntos
Marcação de Genes/métodos , Infecções por HIV/genética , Infecções por HIV/terapia , Interferência de RNA/fisiologia , RNA Interferente Pequeno/uso terapêutico , Síndrome de Imunodeficiência Adquirida/genética , Síndrome de Imunodeficiência Adquirida/terapia , Animais , Técnicas de Transferência de Genes , Genes Virais , Terapia Genética/métodos , Humanos , Modelos Biológicos , RNA Interferente Pequeno/efeitos adversos , Especificidade por Substrato
7.
Inflammation ; 30(1-2): p.28-37, 2007.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib10693

Assuntos
Genética
8.
Exp Biol Med (Maywood) ; 231(6): 824-9, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16741006

RESUMO

CGS 35601 is a triple vasopeptidase inhibitor (VPI) of angiotensin converting enzyme (ACE), neutral endopeptidase (NEP), and endothelin (ET) converting enzyme-1 (ECE-1), with respective IC(50) values of 22, 2, and 55 nM. The aim of the present study was to establish the hemodynamic profile of Zucker diabetic fatty (Zdf)-Fatty rats, a high-fat diet gene-prone model developing spontaneous Type 2 diabetes (T2D) and the effects of CGS 35601. Male Zdf-Fatty (14 weeks, n = 17-23), Zdf-Lean (14 weeks, n = 8-10), and Wistar (14 weeks, n = 9-10) rats on distinct diets were implanted with a catheter in the left carotid and placed individually in a metabolic cage for 30 days. The hemodynamic profile and some metabolic biomarkers were assessed daily. After a 7-day stabilization period, the Zdf-Fatty rats were divided into two groups: Group 1, controls (n = 7-10) receiving vehicle-saline (250 microl/hr) and Group 2, (n = 10-13) receiving increasing doses of CGS 35601 (0.1, 1, and 5 mg/kg/day x 6 days each, intra-arterially) followed by a 5-day washout period. Mean arterial blood pressure (MABP) of young Zdf-Fatty rats was compared with age-matched Zdf-Lean and Wistar rats, which were found similar. MABP decreased by 5.9% (from baseline at 102 +/- 5 to 96 +/- 4 mmHg), 12.7% (to 89 +/- 6 mmHg) and 21.6% (to 80 +/- 4 mmHg), at 0.1, 1, and 5 mg/kg/day, respectively, in CGS 35601-treated Zdf-Fatty rats. Systolic and diastolic blood pressures were similarly reduced. The heart rate was not affected. Hyperglycemic status and insulin-resistance were not modulated by short-term treatment. CGS 35601 presented an excellent short-term safety profile. This novel molecule and class of VPI may be of interest for lowering vascular tone. Further long-term studies, once cardiovascular and renal complications have developed in this T2D rat model are warranted to define the efficacy of this class of VPI.


Assuntos
Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/metabolismo , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/farmacologia , Animais , Ácido Aspártico Endopeptidases/administração & dosagem , Ácido Aspártico Endopeptidases/farmacologia , Combinação de Medicamentos , Enzimas Conversoras de Endotelina , Indóis/administração & dosagem , Indóis/agonistas , Masculino , Metaloendopeptidases/administração & dosagem , Metaloendopeptidases/farmacologia , Neprilisina/administração & dosagem , Neprilisina/farmacologia , Peptidil Dipeptidase A/administração & dosagem , Peptidil Dipeptidase A/farmacologia , Ratos , Ratos Wistar , Ratos Zucker
9.
Exp Biol Med (Maywood) ; 231(6): 830-3, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16741007

RESUMO

We previously reported that CGS 35601, a potent triple inhibitor of angiotensin-converting enzyme, neutral endopeptidase, and endothelin-converting enzyme 1, completely normalized mean arterial blood pressure (MABP) in 36-week-old spontaneously hypertensive rats, a normal renin model. The aim of the present study was to determine the effects of this triple vasopeptidase inhibitor (VPI) on the hemodynamic profile of instrumented, conscious, and unrestrained Dahl salt-sensitive (DSS) rats, a gene-prone, high-salt diet-induced low-renin hypertension model. Male DSS rats (mean weight [+/-SEM], 385 +/- 10 g) were fed a normal diet (Group 1) or a high-salt diet (Groups 2 and 3; 8% NaCl in food) for 6 weeks and then instrumented with a carotid catheter and placed individually in metabolic cages for 30 days. The hemodynamic, hematological, and biochemical profiles were assessed daily. Dose-dependent treatment started after a 7-day stabilization period in Groups 1 and 2 (vehicle dosage, 250 microl/hr) and Group 3 (CGS 35601 dosages of 0.1, 1, and 5 mg/kg/day for 6 days per dose by means of constant intra-arterial infusion), followed by a 5-day washout period. Two additional groups included normotensive Wistar rats (Group 4) and DSS rats that received a double high-salt solid (8% NaCl) and liquid (1% NaCl) diet (Group 5). The MABP in rats receiving CGS 35601 decreased in a dose-dependent fashion toward the baseline level observed in DSS rats receiving a normal diet. The heart rate was unaffected. The hemodynamic profile returned to normal during the washout period. This novel triple VPI is a potent and effective antihypertensive agent with a safe short-term profile that may be of interest for treating hypertension and other cardiovascular diseases. Other hypertensive rat models are being tested.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/farmacologia , Renina/sangue , Sódio na Dieta/farmacologia , Animais , Ácido Aspártico Endopeptidases/administração & dosagem , Ácido Aspártico Endopeptidases/farmacologia , Combinação de Medicamentos , Enzimas Conversoras de Endotelina , Masculino , Metaloendopeptidases/administração & dosagem , Metaloendopeptidases/farmacologia , Neprilisina/administração & dosagem , Neprilisina/farmacologia , Peptidil Dipeptidase A/administração & dosagem , Peptidil Dipeptidase A/farmacologia , Ratos , Ratos Endogâmicos Dahl
10.
Drug Chem Toxicol ; 29(2): 183-202, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16707327

RESUMO

CGS 35601 is a triple vasopeptidase inhibitor (VPI) of angiotensin-converting enzyme, neutral endopeptidase, and endothelin-converting enzyme-1 with respective IC50 values of 22, 2, and 55 nM. We characterized the safety profile and toxicity of escalating doses of CGS 35601 over a 20-day period in chronically instrumented, unrestrained, conscious, male, spontaneously hypertensive rats (SHR). Once instrumented with an arterial catheter, the SHR were placed in metabolic cages allowing daily assessment of hemodynamics and blood sampling for biochemical and hematological measurements. After a 7-day stabilization period, the SHR were divided into 2 groups: Gr. 1, (n = 13 to 18) receiving CGS 35601 at 0.01, 0.1, 1 and 5 mg kg(-1) day(-1) (continuous i.a. infusion) for 5 consecutive days/dose, followed by a 5-day washout; and Gr. 2, (n = 10) receiving vehicle (saline). The highest dose of CGS 35601 dose-dependently reduced MABP from 156 +/- 4 up to 94 +/- 5 mm Hg, whereas heart rate, metabolic, electrolytic, and hematological profiles, growth, diuresis, and renal activity were unaffected, and no hepatic or liver toxicities were observed. These results suggest that this novel triple VPI presents no safety concerns at this stage and may become of interest for the treatment of hypertension and other cardiovascular disorders. Long-term chronic experiments are needed to assess possible angioedema and increases in vascular permeability.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Avaliação Pré-Clínica de Medicamentos , Hipertensão/tratamento farmacológico , Indóis/farmacologia , Metaloendopeptidases/antagonistas & inibidores , Neprilisina/antagonistas & inibidores , Inibidores da Enzima Conversora de Angiotensina/toxicidade , Animais , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Enzimas Conversoras de Endotelina , Frequência Cardíaca/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Hipertensão/enzimologia , Hipertensão/fisiopatologia , Indóis/toxicidade , Masculino , Estrutura Molecular , Ratos , Ratos Endogâmicos SHR
11.
Vascul Pharmacol ; 43(4): 289-301, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16253569

RESUMO

The aim of the present study was to assess several biochemical and physiological endpoint parameters alongside controlled hemorrhagic and recovery phases of chronically instrumented, conscious and unrestrained healthy rats. Male Sprague-Dawley rats (12-14 weeks; 430+/-20 g; n=22-18) were instrumented with a saline-perfused femoral arterial catheter and placed individually in a metabolic cage for up to 20 days, allowing instant assessments of the hemodynamic profile and blood and urine sampling for hematological profile and biochemical measurements to assess hepatic, renal and metabolic functions. In addition, body weight, food and water intake, and diuresis were monitored daily. After a 7-day stabilization period, the rats underwent severe and acute hemorrhagic shock (HS) (removal of 50% of total circulating blood volume), kept in hypovolemic shock for an ischemic period of 50 min and then resuscitated over 10 min. Gr. 1 was re-infused with autologous shed blood (AB; n=10) whereas Gr. 2 was infused 1:1 with a solution of sterile saline-albumin (SA; 7% w/v) (n=8-12). Ischemic rats recovered much more rapidly following AB re-infusion than those receiving SA. Normal hemodynamic and biochemical profiles were re-established after 24 h. Depressed blood pressure lasted 4-5 days in SA rats. The hematological profile in the SA resuscitated rats was even more drastically affected. Circulating plasma concentrations of hemoglobin (-40%), hematocrit (-50%), RBC (-40%) and platelets (-41%) counts were still severely decreased 24 h after the acute ischemic event whereas WBC counts increased 2.2-fold by day 4. It took 5-9 days for these profiles to normalize after ischemia-reperfusion with SA. Diuresis increased in both groups (by 45+/-7% on day 1) but presented distinct electrolytic profiles. Hepatic and renal functions were normal in AB rats whereas altered in SA rats. The present set of experiments enabled us to validate a model of HS in conscious rats and the use of an integrated in vivo platform as a valuable tool to characterize HS-induced stress and to test new classes of blood substitutes in real time, post-event, over days.


Assuntos
Substitutos Sanguíneos/uso terapêutico , Hemodinâmica/efeitos dos fármacos , Choque/tratamento farmacológico , Choque/fisiopatologia , Doença Aguda , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/fisiopatologia , Animais , Biomarcadores , Proteínas Sanguíneas/análise , Modelos Animais de Doenças , Eletrólitos/sangue , Eletrólitos/urina , Testes de Função Renal , Lipídeos/sangue , Falência Hepática Aguda/metabolismo , Falência Hepática Aguda/fisiopatologia , Testes de Função Hepática , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/fisiopatologia , Choque/metabolismo , Telemetria
12.
Inflamm Res ; 53(2): 78-83, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15021973

RESUMO

OBJECTIVE: The effect of bradykinin (B(1) or B(2)) receptor antagonists was studied in allergic and immune-complex-induced lung inflammation. METHODS: Lungs of BALB/c mice were examined 24 h after induction of lung inflammation, either allergic (ovalbumin-sensitized submitted to two aerosol of antigen, one week apart) or immune-complex induced (intratracheal instillation of IgG antibodies followed by intravenous antigen). The bradykinin B(2) receptor antagonist, HOE-140 or bradykinin B(1) receptor antagonist, R-954 were given intraperitoneally (100 microg/kg), 30 min before induction. RESULTS: In allergic inflammation, pre-treatment with R-954 reduced eosinophil infiltration into the lungs, mucus secretion and the airway hyperreactivity to methacholine. Pre-treatment with HOE-140 increased eosinophil infiltration but did not affect the other parameters. In immune-complex inflammation, HOE-140 increased neutrophil infiltration but not their activation nor the hemorrhagic lesions. R-594 pre-treatment did not change the parameters examined. CONCLUSION: These results show important modulatory effects of bradykinin B(1) and B(2) receptor antagonists in both models of lung inflammation.


Assuntos
Antagonistas dos Receptores da Bradicinina , Bradicinina/análogos & derivados , Hipersensibilidade , Doenças do Complexo Imune , Pneumonia/imunologia , Pneumonia/prevenção & controle , Animais , Bradicinina/uso terapêutico , Antagonistas de Receptor B1 da Bradicinina , Antagonistas de Receptor B2 da Bradicinina , Broncoconstrição/efeitos dos fármacos , Eosinófilos/patologia , Masculino , Cloreto de Metacolina/administração & dosagem , Camundongos , Camundongos Endogâmicos BALB C , Muco/metabolismo , Ovalbumina/imunologia , Pneumonia/patologia
13.
Inflammation ; 28(5): 253-61, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16133998

RESUMO

The participation of endothelins (ETs) in a model of neutrophil-dependent lung injury induced by intrabronchial instillation of rabbit antibodies to ovalbumin followed by i.v. injection of the antigens (Arthus reaction) was investigated. Hemorrhagic lesions were evaluated by measuring the extravasations of hemoglobin in lung parenchyma. From 5 min to 24 h after the Arthus reaction (AR), endothelin (ir-ET) levels in bronchoalveolar lavage fluid (BALF) and in plasma were measured by radioimmunoassay. BALF levels of ir-ET were not different between control and AR animals for the first 90 min after the antigen challenge but increased from 2 to 24 h after induction of AR. ET levels in the plasma did not change from the respective controls over the same 24 h period. Increased ir-ET in BALF was not affected by pretreatment with L-NAME (30 mg/kg, i.v.). A PAF antagonist (BN52021; 5 and 10 mg/kg, i.v.) increased ET content in BALF and decreased the intensity of the AR. Thiorphan (2 mg/kg, i.v.) inhibited the AR-induced hemorrhagic lesions in lungs. An ET(A) receptor antagonist, BQ-123 (1 mg/kg, i.v.) potentiated, whereas the ET(B) antagonist, BQ-788 (1 mg/kg, i.v.) inhibited the lung hemorrhage. It is concluded that ETs are released during and play a role in the lung AR.


Assuntos
Reação de Arthus/imunologia , Endotelinas/metabolismo , Hemorragia/imunologia , Pneumopatias/imunologia , Pneumonia/imunologia , Animais , Complexo Antígeno-Anticorpo , Reação de Arthus/sangue , Reação de Arthus/etiologia , Líquido da Lavagem Broncoalveolar/química , Diterpenos/farmacologia , Antagonistas do Receptor de Endotelina A , Antagonistas do Receptor de Endotelina B , Endotelinas/análise , Endotelinas/sangue , Fibrinolíticos/farmacologia , Ginkgolídeos , Hemoglobinas/análise , Hemorragia/etiologia , Hemorragia/metabolismo , Lactonas/farmacologia , Pneumopatias/etiologia , Pneumopatias/metabolismo , Masculino , Neutrófilos/imunologia , Oligopeptídeos/farmacologia , Ovalbumina , Peptídeos Cíclicos/farmacologia , Piperidinas/farmacologia , Pneumonia/patologia , Ratos , Ratos Wistar
14.
Inflamm Res ; 53(12): 653-7, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15654512

RESUMO

OBJECTIVE: Experimental evidence has shown that the bradykinin B1 receptor (BKB1-R) is involved in the development of hyperalgesia associated with diabetes since specific BKB1-R antagonists significantly inhibited the hyperalgesic activity observed in streptozotocin (STZ)-mice in thermal nociceptive tests. MATERIALS AND METHODS: The involvement of the nitric oxide (NO), the substance P (SP) and the calcitonin gene-related peptide (CGRP) pathways in mediating BKB1-R-induced hyperalgesia was evaluated. Diabetes was induced in male CD-1 mice by injecting STZ (200 mg/kg; i.p.). Nociception was assessed using the hot plate and tail immersion tests, one week following the injection of STZ. RESULTS: The nitric oxide synthase (NOS) inhibitors (L-NNA, 20 mg/kg; L-NMMA, 30 mg/kg and AGUA, 50 mg/kg; i.p.), the SP antagonists (sendide and L-732,138, 100 microg/kg; i.v.) and the CGRP antagonist (hCGRP8-37, 100 microg/kg; i.v.) significantly attenuated the hyperalgesic activity and also reversed the potentiating effect of the BKB1- R agonist, DBK on diabetic hyperalgesia in STZ-mice. CONCLUSIONS: These results support the involvement of BKB1-R in the development of diabetic hyperalgesia in STZ-mice through activation of the NO, SP and CGRP pathways.


Assuntos
Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Hiperalgesia/complicações , Hiperalgesia/metabolismo , Receptor B1 da Bradicinina/metabolismo , Transdução de Sinais , Animais , Antagonistas de Receptor B1 da Bradicinina , Peptídeo Relacionado com Gene de Calcitonina/antagonistas & inibidores , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Masculino , Camundongos , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Estreptozocina/farmacologia , Substância P/antagonistas & inibidores , Substância P/metabolismo
15.
16.
Am Heart J ; 142(6): 1056-64, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11717612

RESUMO

OBJECTIVE: Our purpose was to study the changes in vasoconstrictive neurohormones, N-terminal proatrial natriuretic peptide (Nt-proANP), and brain natriuretic peptide (BNP) and their relationship with left ventricular (LV) remodeling soon after anterior myocardial infarction (MI). BACKGROUND: The Healing and Afterload Reducing Therapy (HEART) trial has shown that early use of ramipril improves left ventricular ejection fraction (LVEF) and attenuates LV remodeling when initiated soon after MI. This neurohumoral substudy of HEART investigates the changes in vasoconstrictive and natriuretic peptides and their relationship with LV remodeling. METHODS: One hundred twenty-two patients had blood drawn for the measurement of catecholamines, endothelin-I, angiotensin II, Nt-proANP and BNP, and prostacyclins within 24 hours of an MI, and at 3, 14, and 90 days after the MI. Quantitative echocardiograms were performed at baseline and at 14 days. RESULTS: All neurohormones except angiotensin II (P =.12) and prostaglandins were significantly elevated at baseline. Vasoconstrictive neurohormones decreased significantly over time but remained elevated at 14 days. Both Nt-proANP and BNP were elevated within the first 14 days. BNP decreased significantly by 90 days, whereas Nt-proANP exhibited no change between 14 and 90 days. Ramipril decreased plasma levels of angiotensin II at 3 days but had no effect on the other neurohormones. CONCLUSIONS: Neurohumoral activation occurs and persists in patients with anterior MI and overall preserved LV function. Ramipril had only a modest impact on neurohormones despite its significant benefits on LV remodeling soon after MI.


Assuntos
Fator Natriurético Atrial/sangue , Catecolaminas/sangue , Infarto do Miocárdio/fisiopatologia , Peptídeo Natriurético Encefálico/sangue , Remodelação Ventricular , Angiotensina II/sangue , Biomarcadores/sangue , Dopamina/sangue , Método Duplo-Cego , Epinefrina/sangue , Epoprostenol/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso , Norepinefrina/sangue , Ramipril/administração & dosagem , Volume Sistólico/efeitos dos fármacos
17.
Exp Lung Res ; 27(2): 107-19, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11258800

RESUMO

The effect of a receptor binding protein for tumor necrosis factor (TNFrbp) on cell infiltration, bronchial hyperreactivity, and release of inflammatory mediators were studied following antigen challenge in sensitized rats. A 3-fold increase in total cell number, mainly neutrophils and eosinophils, was noted in bronchoalveolar lavage (BAL) fluid 8 hours after antigen challenge. Antigen challenge also induced a significant hyperreactivity of the lower bronchus to carbachol and serotonin, but did not affect the reactivity of the trachea and upper bronchus. This increased responsiveness of the lower bronchus was transient, being detected 8 hours but not 24 hours after antigen challenge. Thromboxane B2 (TxB2), prostaglandin E2 (PGF2), and nitric oxide (NO) levels increased in the BAL fluid of sensitized rats 8 hours after antigen challenge by 197%, 172%, and 173%, respectively. TNFrbp treatment reduced by 83% the antigen-induced cell infiltration, with neutrophils being the cells most affected. The bronchial hyperreactivity induced by antigen challenge was also significantly inhibited by TNFrbp, whereas TxB2, PGE2, and NO levels in the BAL fluid were not affected. In our animal model, the cell infiltration and bronchial hyperreactivity appear to be mediated to some extent by TNF, but not by prostanoids nor NO.


Assuntos
Hiper-Reatividade Brônquica/imunologia , Broncopneumonia/imunologia , Proteínas de Transporte/farmacologia , Receptores do Fator de Necrose Tumoral , Animais , Hiper-Reatividade Brônquica/patologia , Hiper-Reatividade Brônquica/prevenção & controle , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Broncopneumonia/patologia , Broncopneumonia/prevenção & controle , Carbacol/farmacologia , Proteínas de Transporte/uso terapêutico , Contagem de Células , Movimento Celular/efeitos dos fármacos , Dinoprostona/análise , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Eosinófilos/efeitos dos fármacos , Técnicas In Vitro , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Músculo Liso/fisiologia , Neutrófilos/efeitos dos fármacos , Óxido Nítrico/análise , Ratos , Ratos Wistar , Receptores Tipo I de Fatores de Necrose Tumoral , Serotonina/farmacologia , Tromboxano B2/análise , Receptores Chamariz do Fator de Necrose Tumoral
18.
Am J Physiol Lung Cell Mol Physiol ; 280(4): L732-8, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11238014

RESUMO

Using monolayers of bovine aortic endothelial cells (BAEC) in modified Boyden chambers, we examined the role of prostaglandins (PGs) in the bradykinin (BK)-induced increase of albumin permeability. BK induced a concentration-dependent increase of the permeability of BAEC, which reached 49.9 +/- 1% at the concentration of 10(-8) M. Two inhibitors of the prostaglandin G/H synthase, indomethacin (2.88 microM) and ibuprofen (10 microM), potentiated BK-induced permeability 1.8- and 3.9-fold, respectively. Exogenously administered PGE2 and iloprost, a stable analog of prostacyclin, attenuated the effect of BK in a concentration-dependent manner. Butaprost equally reduced the effect of BK, suggesting the participation of the EP2 receptor in this phenomenon. However, the EP4-selective antagonist AH-23848 did not significantly inhibit the protective effect of PGE2. The inhibitory effect of PGE2 was reversed by the adenylate cyclase inhibitor MDL-12330A (10 microM). These results suggest that BK-induced increase of permeability of BAEC monolayer to (125)I-labeled albumin is negatively regulated by PGs. This postulated autocrine activity of PGs may involve an increase in the intracellular level of cAMP.


Assuntos
Alprostadil/análogos & derivados , Bradicinina/farmacologia , Permeabilidade Capilar/efeitos dos fármacos , Endotélio Vascular/metabolismo , Prostaglandinas/farmacologia , Albumina Sérica/metabolismo , Agonistas Adrenérgicos beta/farmacologia , Albuterol/farmacologia , Alprostadil/farmacologia , Animais , Bovinos , AMP Cíclico/metabolismo , Inibidores de Ciclo-Oxigenase/farmacologia , Dinoprostona/farmacologia , Endotélio Vascular/citologia , Iloprosta/farmacologia
19.
Br J Pharmacol ; 132(5): 999-1008, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11226130

RESUMO

Prostaglandin E(2) (PGE(2)) increased adenosine 3' : 5'-cyclic monophosphate (cyclic AMP) formation in tracheal epithelial cells and concomitantly decreased the production/secretion of immunoreactive endothelin (irET). Naturally occurring prostanoids and selective and non-selective EP receptor agonists showed the following rank order of potency in stimulating cyclic AMP generation by epithelial cells: PGE(2) (EP-selective)>16,16-dimethyl PGE(2) (EP-selective)>11-deoxy PGE(2) (EP-selective)>>>iloprost (IP/EP(1)/EP(3)-selective), butaprost (EP(2)-selective), PGD(2) (DP-selective), PGF(2alpha) (FP-selective). The lack of responsiveness of the latter prostanoids indicated that the prostanoid receptor present in these cells is not of the DP, FP, IP, EP(1), EP(2) or EP(3) subtype. Pre-incubating the cells with the selective TP/EP(4)-receptor antagonists AH23848B and AH22921X antagonized the PGE(2)-evoked cyclic AMP generation. This suggested that EP(4) receptors mediate PGE(2) effects. However, in addition to any antagonistic effects at EP(4)-receptors, both compounds, to a different extent, modified cyclic AMP metabolism. The selective EP(1), DP and EP(2) receptor antagonist (AH6809) failed to inhibit PGE(2)-evoked cyclic AMP generation which confirmed that the EP(2) receptor subtype did not contribute to the change in cyclic AMP formation in these cells. The PGE(2)-induced inhibition of irET production by guinea-pig tracheal epithelial cells was due to cyclic AMP generation and activation of the cyclic AMP-dependent protein kinase since this effect was reverted by the cyclic AMP antagonist Rp-cAMPS. These results provide the first evidence supporting the existence of a functional prostaglandin E(2) receptor that shares the pharmacological features of the EP(4)-receptor subtype in guinea-pig tracheal epithelial cells. These receptors modulate cyclic AMP formation as well as ET-1 production/secretion in these cells.


Assuntos
AMP Cíclico/metabolismo , Dinoprostona/farmacologia , Endotelina-1/antagonistas & inibidores , Células Epiteliais/efeitos dos fármacos , Receptores de Prostaglandina E/efeitos dos fármacos , Adenosina/farmacologia , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Endotelina-1/metabolismo , Células Epiteliais/metabolismo , Cobaias , Masculino , Receptores de Prostaglandina E/metabolismo , Receptores de Prostaglandina E Subtipo EP4 , Traqueia/efeitos dos fármacos , Traqueia/metabolismo , Vasodilatadores/farmacologia
20.
J Soc Biol ; 195(4): 401-11, 2001.
Artigo em Francês | MEDLINE | ID: mdl-11938557

RESUMO

Oxidative stress which results from an imbalance between oxidant production and antioxidant defense mechanisms can promote modifications of lipids, proteins and nucleic acids. This review focuses on the different pathways leading to Reactive Oxygen Species (ROS) production in particular on NADPH oxidase activation. This enzyme is localized in numerous cells including phagocytes and vascular cells and composed of membrane and cytosolic sub-units. The activation of the NADPH oxidase is largely involved in inflammation associated diseases such as asthma, Systemic Inflammatory Response Syndrome and aging associated diseases such as atherosclerosis and neurodeneratives diseases. The modulation of NADPH oxidase could be a way to limit or prevent the development of these diseases.


Assuntos
NADPH Oxidases/metabolismo , Estresse Oxidativo , Superóxidos/metabolismo , Terapêutica , Ânions , Arteriosclerose/enzimologia , Arteriosclerose/prevenção & controle , Ativação Enzimática , Inibidores Enzimáticos/uso terapêutico , Humanos , Inflamação/enzimologia , Inflamação/prevenção & controle , NADPH Oxidases/antagonistas & inibidores , NADPH Oxidases/genética , Doenças Neurodegenerativas/enzimologia , Doenças Neurodegenerativas/prevenção & controle , Espécies Reativas de Oxigênio
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