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1.
Pharmacol Biochem Behav ; 233: 173674, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37949377

RESUMO

Major depressive disorder (MDD) is a debilitating illness that affects millions of people worldwide. Currently available antidepressants often take weeks to months to reach their full effect, which leads to an increased risk of suicidal behavior in patients with MMD. Intranasally, esketamine has emerged as an alternative to current antidepressants because of its rapid onset and long-lasting effects in patients with MDD. Animal models are useful for the initial pharmacological screening and for a better understanding of the mechanisms underlying the effects of new drugs with potential against MDD. There is a lack of data on alternative routes of drug administration, either oral or injectable, that can be used in preclinical studies. This study aimed to test whether ketamine has antidepressant-like effects in mice when administered via nebulization using a low-cost apparatus. When mice whose depressive-like behavior was induced by corticosterone were treated with nebulized ketamine at concentrations of 1.3, 2.6, and 5.2 mg/mL, immobility was reduced by 38.6 %, 62.0 %, and 61.1 %, respectively, in the forced swimming test (FST) and 43.6 %, 42.1 %, and 57.9 %, respectively, in the tail suspension test (TST). When depression-like behavior was induced by dexamethasone, nebulization with ketamine reduced immobility by 79.7 %, 49.2 %, and 44.4 % in the FST and 80.9 %, 71.4 %, and 80.4 %, respectively, in the TST. When depression-like behavior was induced by the association between dexamethasone and unpredictable chronic mild stress (UCMS) exposure, immobility was reduced by 26.1 %, 55.3 %, and 19.1 % in FST. Mice treated with nebulized ketamine did not show significant changes in the distance covered or in the time spent moving in the open field test. The efficacy of intraperitoneal and nebulized ketamine is equivalent, which shows that nebulization can be an alternative inexpensive route of drug administration for behavioral studies in rodents.


Assuntos
Transtorno Depressivo Maior , Ketamina , Humanos , Camundongos , Animais , Natação , Ketamina/farmacologia , Ketamina/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Elevação dos Membros Posteriores , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Modelos Animais de Doenças , Dexametasona/uso terapêutico , Depressão/tratamento farmacológico
2.
Chem Biol Interact ; 348: 109656, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34516975

RESUMO

Asthma is a chronic inflammatory disease that targeting lower airways, being characterized by bronchial smooth muscle hyper responsiveness and mucus hypersecretion. Asthma is considered the most common respiratory disease in the world, affecting approximately 235 million individuals. The main therapy sometimes fails to establish clinical improvement in patients, which leads to a constant search for new alternatives. Camphor is a transparent solid monoterpene with a strong aroma, which due to its high lipophilicity is insoluble in water. Nanostructured carrier systems have shown promise as a delivery system for lipophilic compounds such as monoterpenes. Therefore, the objective of this work was to evaluate the relaxant effect of nanoemulsified camphor (NEC), as well as the mechanism of action of that monoterpene, in isolated rat trachea. The results obtained demonstrated that NEC promote relaxation of the isolated rat trachea when smooth muscle contraction was induced by both carbachol (CCh) and KCl, presenting a pCE50 of 2.25 ± 0.27 and 3.30 ± 0.07, respectively. In the presence of dexamethasone (DEXA), tetraethylammonium (TEA), glibenclamide (GLIB), 1H-[1,2,4]-oxadiazole-[4,3,-a]-quinoxaline-1-one (ODQ) and ruthenium red (RR) there was a significant difference in at least one of the evaluated pharmacological parameters, such as concentration-response curves shape, Emax or pCE50. As conclusion, NEC may be involved with ß-adrenergic receptors, channels for K+ sensitive to ATP (KATP) or Channels for K+ opened by Ca2+ (KCa), increase in prostanoids and with receptor channel with transient potential (TRPv). In conclusion, ß-adrenergic receptors, prostanoids, nitric oxide (NO), ATP-sensitive K+ channels (KATP), Ca2+-opened K+ channels (KCa), and transient receptor potential cation channel subfamily V (TRPV) are involved in the relaxing effect of NEC. In addition, the mechanism of action of NEC may be involved with the signal transduction pathway Nitric Oxide/soluble guanylyl cyclase/cGMP/cGMP-activated protein kinase. NEC, therefore, demonstrates spasmolytic activity when presenting tracheal relaxation compared to CCh and KCl contracturants.


Assuntos
Cânfora/química , Cânfora/farmacologia , Relaxamento Muscular/efeitos dos fármacos , Nanoestruturas/química , Traqueia/efeitos dos fármacos , Traqueia/fisiologia , Animais , Emulsões , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Músculo Liso/fisiologia , Ratos
3.
Naunyn Schmiedebergs Arch Pharmacol ; 394(5): 885-902, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33205250

RESUMO

In the field of experimental pharmacology, researchers continuously investigate new relaxant agents of the airway smooth muscle cells (ASMCs), since the pathophysiology of respiratory illnesses, such as asthma, involves hyperresponsiveness and changes in ASMC homeostasis. In this scenario, labdane-type diterpenes, like forskolin (FSK), are a class of compounds known for their relaxing action on smooth muscle cells (SMCs), being this phenomenon related to the direct activation of AC-cAMP-PKA pathway. Considering the continuous effort of our group to study the mechanism of action and prospecting for compounds isolated from natural sources, in this paper, we presented how the diterpene 8(17),12E,14-labdatrien-18-oic acid (LBD) promotes relaxant effect on ASMC, performing in vitro experiments using isolated guinea pig trachea and in silico molecular docking/dynamics simulations. In vitro experiments showed that in the presence of aminophylline, FSK and LBD had their relaxant effect potentiated (EC50 from 1.4 ± 0.2 × 10-5 M to 1.5 ± 0.3 × 10-6 M for LBD and from 2.0 ± 0.2 × 10-7 M to 6.4 ± 0.4 × 10-8 M for FSK) while in the presence of Rp-cAMPS this effect was attenuated (EC50 from 1.4 ± 0.2 × 10-5 M to 3 × 10-4 M for LBD and from 2.0 ± 0.2 × 10-7 to 3.1 ± 1.0 × 10-6 M for FSK). Additionally, in silico simulations evidenced that the lipophilic character of LBD is probably responsible for its stability on AC binding site. LBD presented two preferential orientations, where the double bonds of the isoprene moiety as well as the unique polar group (carboxylic acid) in this compound form important anchoring points. In this sense, we consider that the LBD can interact stabilizing the catalytic dimmer of AC as the FSK, although less efficiently.


Assuntos
Diterpenos/farmacologia , Relaxamento Muscular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Traqueia/efeitos dos fármacos , Aminofilina/farmacologia , Animais , Sítios de Ligação , Colforsina/farmacologia , Simulação por Computador , Diterpenos/administração & dosagem , Diterpenos/química , Feminino , Cobaias , Masculino , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Miócitos de Músculo Liso/metabolismo , Traqueia/citologia
4.
Fundam Clin Pharmacol ; 33(2): 148-158, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30240490

RESUMO

The monoterpene alcohol (-)-borneol has many biological effects such as sedative, anti-inflammatory, analgesic, anti-nociceptive, antithrombotic and vasorelaxant effects. Our objective in this study was to investigate the mechanism of action of (-)-borneol and determine its vasorelaxant effect. (-)-Borneol was tested on isolated aortic rings contracted with PE (10-6  m). This study was performed in the absence or in the presence of endothelium, L-NAME (100 µm), indomethacin (10 µm), TEA (1 and 10 mm), 4-AP (1 mm) or glibenclamide (1 mm) to assess the participation of EDRF, nitric oxide, prostanoids and potassium channels on the relaxing effect of (-)-borneol. In this work, (-)-borneol induced a relaxant effect in aortic rings, with and without endothelium, in a concentration-dependent manner. The pharmacological characterization obtained using L-NAME, indomethacin, TEA, 4-AP and glibenclamide demonstrates that the effect of (-)-borneol was modified in the presence of L-NAME, indomethacin and glibenclamide showing that these signal transduction pathways are involved in the relaxing effect of the monoterpene. (-)-Borneol has a vasorelaxant effect that depends on the presence of vascular endothelium, with the participation of nitric oxide and prostanoids. Also, (-)-borneol displayed a direct action on the vascular smooth muscle, greatly dependent on KATP channels.


Assuntos
Aorta/efeitos dos fármacos , Canfanos/farmacologia , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Animais , Aorta/metabolismo , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Técnicas In Vitro , Canais KATP/metabolismo , Masculino , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Óxido Nítrico/metabolismo , Prostaglandinas/metabolismo , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos
5.
J Viral Hepat ; 25(4): 335-343, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29091321

RESUMO

Vibration-controlled transient elastography (VCTE) is widely used for noninvasive fibrosis staging in chronic hepatitis C. However, internal validation is based solely on variability and success rate and lacks reproducible quality indicators. We analysed the graphic representation of shear wave propagation in comparison with morphometric results of liver biopsy, eliminating observer variability bias. Individual elastograms were classified according to two morphologic criteria: extension of wave propagation (length of the graphic representation) and shear wave dispersal (level of parallelism displayed in the elastogram). Then, a score based on these criteria stratified the elastogram in classes I through III (highest to lowest technical quality). Liver stiffness results of each measurement were compared with collagen contents in liver biopsy by morphometric analysis. A total of 3243 elastograms were studied (316 patients). Digital morphometry in liver biopsy showed significant fibrosis in 66% of samples and advanced fibrosis in 31%. Elastogram quality analysis resulted in 1438 class I measurements (44%), 1070 class II (34%) and 735 class III. Area under the receiver operating curve (AUROC) for severe fibrosis according to class (I, II and III) was 0.941, 0.887 and 0.766, respectively. For advanced fibrosis, AUROCs were 0.977, 0.883 and 0.781, respectively. Spearman's correlation testing for all classes and levels of fibrosis demonstrated significant independent association (r2  = -.95, P < .01). Our study is the first to propose measurable quality criteria for VTCE and to validate them against objective assessment of liver biopsy through digital morphometric imaging analysis. We concluded that VCTE performance is significantly influenced by quality assessment of individual measurements. Considering these criteria in clinical practice may improve accuracy.


Assuntos
Biópsia , Técnicas de Imagem por Elasticidade/métodos , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/patologia , Histocitoquímica/métodos , Fígado/patologia , Índice de Gravidade de Doença , Adulto , Idoso , Colágeno/análise , Feminino , Hepatite C Crônica/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC
6.
Braz J Med Biol Res ; 49(7)2016 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-27356107

RESUMO

The aim of this study was to determine risk factors for adverse events (AE)-related treatment discontinuation and severe anemia among patients with chronic hepatitis C virus (HCV) genotype 1 infection, treated with first-generation protease inhibitor (PI)-based therapy. We included all patients who initiated treatment with PI-based therapy at a Brazilian university hospital between November 2013 and December 2014. We prospectively collected data from medical records using standardized questionnaires and used Epi Info 6.0 for analysis. Severe anemia was defined as hemoglobin ≤8.5 mg/dL. We included 203 patients: 132 treated with telaprevir (TVR) and 71 treated with boceprevir (BOC). AE-related treatment discontinuation rate was 19.2% and anemia was the main reason (38.5%). Risk factors for treatment discontinuation were higher comorbidity index (OR=1.85, CI=1.05-3.25) for BOC, and higher bilirubin count (OR=1.02, CI=1.01-1.04) and lower BMI (OR=0.98, CI=0.96-0.99) for TVR. Severe anemia occurred in 35 (17.2%) patients. Risk factors for this outcome were lower estimated glomerular filtration rate (eGFR; OR=0.95, CI=0.91-0.98) for patients treated with TVR, and higher comorbidity index (OR=2.21, CI=1.04-4.67) and ribavirin dosage (OR=0.84, CI=0.72-0.99) for those treated with BOC. Fifty-five (57.3%) patients treated with TVR and 15 (27.3%) patients treated with BOC achieved sustained virological response (SVR). Among patients who received TVR and interrupted treatment due to AE (n=19), only 26.3% (n=5) achieved SVR (P=0.003). Higher number of comorbidities, lower eGFR and advanced liver disease are associated with severe anemia and early treatment cessation, which may compromise SVR achievement.


Assuntos
Anemia/etiologia , Hepatite C Crônica/tratamento farmacológico , Oligopeptídeos/administração & dosagem , Prolina/análogos & derivados , Inibidores de Proteases/administração & dosagem , Adulto , Idoso , Antivirais/administração & dosagem , Feminino , Taxa de Filtração Glomerular , Hepatite C Crônica/complicações , Hepatite C Crônica/virologia , Humanos , Interferon-alfa/administração & dosagem , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/efeitos adversos , Polietilenoglicóis/administração & dosagem , Prolina/administração & dosagem , Prolina/efeitos adversos , Estudos Prospectivos , Inibidores de Proteases/efeitos adversos , Proteínas Recombinantes/administração & dosagem , Ribavirina/administração & dosagem , Fatores de Risco , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Resposta Viral Sustentada , Fatores de Tempo , Falha de Tratamento , Adulto Jovem
7.
Braz. j. med. biol. res ; 49(7): e5300, 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-785056

RESUMO

The aim of this study was to determine risk factors for adverse events (AE)-related treatment discontinuation and severe anemia among patients with chronic hepatitis C virus (HCV) genotype 1 infection, treated with first-generation protease inhibitor (PI)-based therapy. We included all patients who initiated treatment with PI-based therapy at a Brazilian university hospital between November 2013 and December 2014. We prospectively collected data from medical records using standardized questionnaires and used Epi Info 6.0 for analysis. Severe anemia was defined as hemoglobin ≤8.5 mg/dL. We included 203 patients: 132 treated with telaprevir (TVR) and 71 treated with boceprevir (BOC). AE-related treatment discontinuation rate was 19.2% and anemia was the main reason (38.5%). Risk factors for treatment discontinuation were higher comorbidity index (OR=1.85, CI=1.05-3.25) for BOC, and higher bilirubin count (OR=1.02, CI=1.01-1.04) and lower BMI (OR=0.98, CI=0.96-0.99) for TVR. Severe anemia occurred in 35 (17.2%) patients. Risk factors for this outcome were lower estimated glomerular filtration rate (eGFR; OR=0.95, CI=0.91-0.98) for patients treated with TVR, and higher comorbidity index (OR=2.21, CI=1.04-4.67) and ribavirin dosage (OR=0.84, CI=0.72-0.99) for those treated with BOC. Fifty-five (57.3%) patients treated with TVR and 15 (27.3%) patients treated with BOC achieved sustained virological response (SVR). Among patients who received TVR and interrupted treatment due to AE (n=19), only 26.3% (n=5) achieved SVR (P=0.003). Higher number of comorbidities, lower eGFR and advanced liver disease are associated with severe anemia and early treatment cessation, which may compromise SVR achievement.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Anemia/etiologia , Hepatite C Crônica/tratamento farmacológico , Oligopeptídeos/administração & dosagem , Prolina/análogos & derivados , Inibidores de Proteases/administração & dosagem , Antivirais/administração & dosagem , Taxa de Filtração Glomerular , Hepatite C Crônica/complicações , Hepatite C Crônica/virologia , Interferon-alfa/administração & dosagem , Modelos Logísticos , Oligopeptídeos/efeitos adversos , Polietilenoglicóis/administração & dosagem , Prolina/administração & dosagem , Prolina/efeitos adversos , Estudos Prospectivos , Inibidores de Proteases/efeitos adversos , Proteínas Recombinantes/administração & dosagem , Ribavirina/administração & dosagem , Fatores de Risco , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Resposta Viral Sustentada , Fatores de Tempo , Falha de Tratamento
8.
Transplant Proc ; 46(9): 3039-42, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25420817

RESUMO

INTRODUCTION: Co-infected HIV and hepatitis subjects are candidates for a liver transplantation because of progressive liver disease. Chronic liver disease, co-infected or not, requires assessment of respiratory function before liver transplantation. The respiratory evaluation of these 2 groups compared with healthy individuals can define deficits, and this can impair a full recovery after transplant surgery. OBJECTIVE: This study sought to compare the respiratory profile in co-infected patients with chronic liver disease who are candidates for liver transplantation with that of healthy subjects. METHODS: Through respiratory evaluation of flows and lung volumes (spirometry), muscle activity (surface electromyography), and maximum pressure (manovacuometer), 250 people were distributed into 3 groups: 14 patients with HIV and liver disease, 65 healthy subjects, and 171 patients with chronic liver disease. The mean age (years) was respectively 47.5 ± 6.2, 48.3 ± 14.1, and 52.9 ± 8.5. The average body mass index (kg/m(2)) of the groups was 24.6 ± 4.5, 26.0 ± 3.2, and 28.5 ± 5.3, respectively. RESULTS: There was a statistical difference among the groups in the root means square (RMS) rectus abdominis (µV) (P = .0016), RMS diaphragm (µV) (P = .0001), maximal inspiratory pressure (cmH2O) (P = .001), forced exhaled volume at the end of first second (%) (P = .002), and maximal mid expiratory flow 25% to 75% (%) (P = .0001) for the Kruskal-Wallis test. The multivariate analysis among the groups showed that the RMS diaphragm had a tendency to discriminate the co-infected subjects. CONCLUSIONS: The co-infected HIV group showed a muscle deficit of diaphragm and rectus abdominis activity, and the liver disease group showed lower indexes in volumes and respiratory flows.


Assuntos
Coinfecção/fisiopatologia , Doença Hepática Terminal/cirurgia , Infecções por HIV/epidemiologia , Hepatite/epidemiologia , Hepatopatias/epidemiologia , Transplante de Fígado , Adulto , Coinfecção/cirurgia , Diafragma/fisiopatologia , Eletromiografia , Doença Hepática Terminal/fisiopatologia , Feminino , Infecções por HIV/fisiopatologia , Hepatite/fisiopatologia , Hepatite/cirurgia , Humanos , Hepatopatias/fisiopatologia , Hepatopatias/cirurgia , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Força Muscular , Reto do Abdome/fisiopatologia , Testes de Função Respiratória , Espirometria
9.
Braz. j. med. biol. res ; 38(12): 1729-1734, Dec. 2005. ilus
Artigo em Inglês | LILACS | ID: lil-417199

RESUMO

Hepatitis C virus (HCV) is essentially hepatotropic but its manifestations can extend beyond the liver. It can be associated with autoimmune diseases, such as mixed cryoglobulinemia, membranoproliferative glomerulonephritis, autoimmune thyroiditis, and lymphoproliferative disorders. The mechanisms that trigger these manifestations are not completely understood. We describe a 48-year-old man with chronic HCV infection (circulating HCV RNA and moderate hepatitis as indicated by liver biopsy), cryoglobulinemia, and sensory and motor peripheral neuropathy. The diagnosis of multineuropathy was confirmed by clinical examination and electromyographic tests. A nerve biopsy revealed an inflammatory infiltrate in the perineurial space and signs of demyelination and axonal degeneration. The patient had no improvement of neurological symptoms with the use of analgesics and neuro-modulators. He was then treated with interferon-alpha (3 million units subcutaneously, 3 times per week) and ribavirin (500 mg orally, twice a day) for 48 weeks. Six months after the end of therapy, the patient had sustained viral response (negative HCV RNA) and remission of neurological symptoms, but cryoglobulins remained positive. A review of the literature on the pathogenesis and treatment of neurological manifestations associated with HCV infection is presented. This report underscores the need for a thorough evaluation of HCV-infected patients because of the possibility of extrahepatic manifestations. Antiviral treatment with interferon and ribavirin can be effective and should be considered in patients with neurological complications associated with HCV infection.


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Crioglobulinemia/etiologia , Hepatite C/complicações , Polineuropatias/etiologia , Antivirais/uso terapêutico , Eletromiografia , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite C/tratamento farmacológico , Técnicas Imunoenzimáticas , Interferon-alfa/uso terapêutico , Polineuropatias/patologia , Ribavirina/uso terapêutico
10.
Braz J Med Biol Res ; 38(12): 1729-34, 2005 12.
Artigo em Inglês | MEDLINE | ID: mdl-16302087

RESUMO

Hepatitis C virus (HCV) is essentially hepatotropic but its manifestations can extend beyond the liver. It can be associated with autoimmune diseases, such as mixed cryoglobulinemia, membranoproliferative glomerulonephritis, autoimmune thyroiditis, and lymphoproliferative disorders. The mechanisms that trigger these manifestations are not completely understood. We describe a 48-year-old man with chronic HCV infection (circulating HCV RNA and moderate hepatitis as indicated by liver biopsy), cryoglobulinemia, and sensory and motor peripheral neuropathy. The diagnosis of multineuropathy was confirmed by clinical examination and electromyographic tests. A nerve biopsy revealed an inflammatory infiltrate in the perineurial space and signs of demyelination and axonal degeneration. The patient had no improvement of neurological symptoms with the use of analgesics and neuro-modulators. He was then treated with interferon-alpha (3 million units subcutaneously, 3 times per week) and ribavirin (500 mg orally, twice a day) for 48 weeks. Six months after the end of therapy, the patient had sustained viral response (negative HCV RNA) and remission of neurological symptoms, but cryoglobulins remained positive. A review of the literature on the pathogenesis and treatment of neurological manifestations associated with HCV infection is presented. This report underscores the need for a thorough evaluation of HCV-infected patients because of the possibility of extrahepatic manifestations. Antiviral treatment with interferon and ribavirin can be effective and should be considered in patients with neurological complications associated with HCV infection.


Assuntos
Crioglobulinemia/etiologia , Hepatite C/complicações , Polineuropatias/etiologia , Antivirais/uso terapêutico , Eletromiografia , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite C/tratamento farmacológico , Humanos , Técnicas Imunoenzimáticas , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Polineuropatias/patologia , Ribavirina/uso terapêutico
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