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1.
Med Mycol ; 62(5)2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38692846

RESUMO

Candida albicans is a pathogenic fungus that undergoes morphological transitions between hyphal and yeast forms, adapting to diverse environmental stimuli and exhibiting distinct virulence. Existing research works on antifungal blue light (ABL) therapy have either focused solely on hyphae or neglected to differentiate between morphologies, obscuring potential differential effects. To address this gap, we established a novel dataset of 150 C. albicans-infected mouse skin tissue slice images with meticulously annotated hyphae and yeast. Eleven representative convolutional neural networks were trained and evaluated on this dataset using seven metrics to identify the optimal model for segmenting hyphae and yeast in original high pixel size images. Leveraging the segmentation results, we analyzed the differential impact of blue light on the invasion depth and density of both morphologies within the skin tissue. U-Net-BN outperformed other models in segmentation accuracy, achieving the best overall performance. While both hyphae and yeast exhibited significant reductions in invasion depth and density at the highest ABL dose (180 J/cm2), only yeast was significantly inhibited at the lower dose (135 J/cm2). This novel finding emphasizes the importance of developing more effective treatment strategies for both morphologies.


We studied the effects of blue light therapy on hyphal and yeast forms of Candida albicans. Through image segmentation techniques, we discovered that the changes in invasion depth and density differed between these two forms after exposure to blue light.


Assuntos
Candida albicans , Hifas , Animais , Camundongos , Candida albicans/efeitos da radiação , Pele/microbiologia , Fototerapia/métodos , Processamento de Imagem Assistida por Computador/métodos , Luz , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Redes Neurais de Computação , Modelos Animais de Doenças , Candidíase/microbiologia
2.
Zool Res ; 43(1): 64-74, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-34845879

RESUMO

Retinal angiogenesis is a critical process for normal retinal function. However, uncontrolled angiogenesis can lead to pathological neovascularization (NV), which is closely related to most irreversible blindness-causing retinal diseases. Understanding the molecular basis behind pathological NV is important for the treatment of related diseases. Twist-related protein 1 (TWIST1) is a well-known transcription factor and principal inducer of epithelial-mesenchymal transition (EMT) in many human cancers. Our previous study showed that Twist1 expression is elevated in pathological retinal NV. To date, however, the role of TWIST1 in retinal pathological angiogenesis remains to be elucidated. To study the role of TWIST1 in pathological retinal NV and identify specific molecular targets for antagonizing pathological NV, we generated an inducible vascular endothelial cell (EC)-specific Twist1 transgenic mouse model ( Tg-Twist1 iEC+ ). Whole-mount retinas from Tg-Twist1 iEC+ mice showed retarded vascular progression and increased vascular density in the front end of the growing retinal vasculature, as well as aneurysm-like pathological retinal NV. Furthermore, overexpression of Twist1 in the ECs promoted cell proliferation but disturbed cell polarity, thus leading to uncontrolled retinal angiogenesis. TWIST1 promoted pathological NV by activating the Wnt/ß-catenin signaling pathway and inducing the expression of NV formation-related genes, thereby acting as a 'valve' in the regulation of pathological angiogenesis. This study identified the critical role of TWIST1 in retinal pathological NV, thus providing a potential therapeutic target for pathological NV.


Assuntos
Neovascularização Patológica , Neovascularização Retiniana , Doenças dos Roedores , Animais , Células Endoteliais , Camundongos , Camundongos Transgênicos , Neovascularização Patológica/genética , Neovascularização Patológica/veterinária , Neovascularização Retiniana/genética , Neovascularização Retiniana/veterinária , Proteína 1 Relacionada a Twist/genética
3.
Food Funct ; 12(15): 6915-6924, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34132294

RESUMO

Reactive oxygen species (ROS), especially hydrogen peroxide (H2O2), have recently been reported to cause a significant increase in the production and expression of matrix metalloproteinases (MMPs), which are closely correlated with lung cancer metastasis. The aim of the present study is to determine the inhibitory effects of a polysaccharide isolated from Ulva prolifera O.F. Müller (U. prolifera) on the invasive potential of non-small cell lung cancer (NSCLC) cells, and further to explore the underlying mechanisms connected to that potential. The data showed that increased MMP-9 resulting from H2O2 exposure was mediated by activating mitogen-activated protein kinases (MAPKs). Pre-treatment with polysaccharides suppressed the activation of H2O2-mediated MAPK pathways and cell invasion. Hence, MMP-9 production triggered by H2O2 was demonstrated by activating MAPK signaling in a Myc-dependent manner. Taken together, these results suggested that polysaccharides suppress H2O2-induced cell invasion by inhibiting Myc-mediated MMP-9 gene transcription through the MAPK signaling pathway in A549 and NCI-H1650 cells. Our data also suggested that polysaccharides may be useful in minimizing the development of lung cancer metastasis. In the future, pretreatment with polysaccharides because of their antioxidant properties might be beneficial to enhance surgical outcomes.


Assuntos
Proliferação de Células/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Ulva/química , Células A549 , Linhagem Celular Tumoral , Humanos , Peróxido de Hidrogênio/farmacologia , Metaloproteinase 9 da Matriz/metabolismo
4.
Life Sci ; 278: 119630, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34004257

RESUMO

Sortilin is found to regulate proliferation and death of different cells, while its role in regulating keratinocyte proliferation and apoptosis is still unknown. In this study, we found that sortilin levels significantly increased in psoriasis patients, and sortilin suppression eliminated the proliferation of HaCaT cells induced by M5 cocktail solution and enhanced the levels of cleaved caspase 3 protein and the Bax/Bcl-2 ratio; however, levels of p-PI3K and p-AKT were decreased. In addition, sortilin silencing remitted the characteristic changes associated with psoriasis-like skin lesions. In summary, suppressed sortilin expression helped inhibit keratinocyte proliferation in HaCaT cells by inactivating PI3K/AKT signaling, which provides a new target for the therapy of psoriasis.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/farmacologia , Apoptose , Proliferação de Células , Queratinócitos/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Psoríase/patologia , Adolescente , Adulto , Idoso , Animais , Estudos de Casos e Controles , Feminino , Regulação da Expressão Gênica , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Psoríase/tratamento farmacológico , Psoríase/metabolismo , Adulto Jovem
5.
Neoplasma ; 68(3): 509-518, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33502891

RESUMO

This study aims to investigate the role of the long non-coding RNA (lncRNA) HOX transcript antisense RNA (HOTAIR) in the regulation of anoikis resistance of ovarian cancer cells, a prerequisite for metastasis and chemoresistance in ovarian cancer cells. Ovarian cancer SKOV3 cells were cultured in an ultra-low attachment system to establish an anoikis model. The relationship between cellular anoikis capability and HOTAIR expression level was studied by flow cytometry and RT-PCR. The ability of spheroid formation, migration, and invasion of the suspended cells was assessed following the knockdown of HOTAIR expression. The expression of EZH2, H3K27me3, representative targets of EZH2, and anoikis-related biomarkers was also detected. An increase in the duration of suspension culture time rendered the SKOV3 cells anoikis-resistant with a significantly lower apoptotic rate compared to the adherent cells. HOTAIR expression in the suspension cells increased significantly, while that in the adherent cells did not. Following small interfering RNA (siRNA)-mediated knockdown of HOTAIR expression, the abilities of anoikis resistance, migration, and invasion decreased in the suspension cells. Knockdown of HOTAIR levels also reduced the spheroid forming ability of the tumor cells in continuous suspension cultures. Moreover, EZH2 expression correlated with HOTAIR expression, thus regulating the expression of miR-193a and DOK2 via introducing H3K27me3. Western blot analysis of anoikis-related markers showed that N-cadherin, ZEB1, and TWIST1 were downregulated following inhibition of HOTAIR, while E-cadherin and ErbB3 were upregulated. In conclusion, HOTAIR enhances the anoikis resistance and spheroid forming ability of ovarian cancer cells by recruiting EZH2 and influencing H3K27 methylation that may contribute to migration, invasion, and chemoresistance of ovarian cancer cells.


Assuntos
Neoplasias Ovarianas , RNA Longo não Codificante , Anoikis/genética , Linhagem Celular Tumoral , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Metilação , Neoplasias Ovarianas/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
6.
J Clin Pharmacol ; 60(1): 16-27, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31448420

RESUMO

Intravenous administration of acetaminophen is an alternative to the oral and rectal routes, which may be contraindicated in particular clinical settings. This randomized, placebo-controlled study of intravenous acetaminophen (Ofirmev, Mallinckrodt Pharmaceuticals, Bedminster, New Jersey) in neonate and infant patients with acute postoperative pain assessed pharmacokinetics (PK) and safety, in addition to efficacy and pharmacodynamics of repeated doses administered over 24 hours. Neonate and infant patients (<2 years of age) who were undergoing surgery or had experienced a traumatic injury and were expected to need pain management for at least 24 hours were enrolled. Subjects were randomly assigned to receive intravenous acetaminophen low dose, intravenous acetaminophen high dose, or placebo. A population PK model of intravenous acetaminophen was updated by combining 581 samples from the current study of 158 neonate and infant subjects with results from a previously developed model. The individual predicted-versus-observed concentrations plots showed that the structural PK model fit the blood and plasma acetaminophen concentration-versus-time profiles in the active and placebo groups. Terminal elimination half-life was prolonged in neonates and younger infants and in intermediate and older infants similar to values in adults. When compared with placebo, total rescue opioid consumption was similar and significantly fewer intravenous acetaminophen patients prematurely discontinued because of treatment-emergent adverse events (P < .01). For intravenous acetaminophen, neonates receiving 12.5 mg/kg every 6 hours had PK profiles similar to younger, intermediate, and older infants, adolescents, and adults weighing <50 kg receiving 15 mg/kg every 6 hours and adults ≥ 50 kg receiving 1000 mg every 6 hours.


Assuntos
Acetaminofen/administração & dosagem , Acetaminofen/farmacocinética , Analgésicos não Narcóticos/administração & dosagem , Analgésicos não Narcóticos/farmacocinética , Dor Pós-Operatória/tratamento farmacológico , Acetaminofen/efeitos adversos , Acetaminofen/uso terapêutico , Analgésicos não Narcóticos/efeitos adversos , Analgésicos não Narcóticos/uso terapêutico , Relação Dose-Resposta a Droga , Feminino , Humanos , Lactente , Recém-Nascido , Infusões Intravenosas , Masculino , Manejo da Dor , Dor Pós-Operatória/metabolismo , Resultado do Tratamento
7.
Mol Med Rep ; 18(3): 3537-3543, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30066937

RESUMO

Aloe vera is a traditional wound­healing medicine used for the treatment of skin disorders. Aloe polysaccharide (APS) is the main macromolecule of Aloe vera, which contributes to its function. Psoriasis is an immune­mediated chronic inflammatory disease, which affects 2­3% of the general population. The conventional remedies used to treat psoriasis demonstrate limited effects; therefore, natural products, including Aloe vera, are being taken into consideration. However, the effects of APS on the treatment of psoriasis and the underlying mechanisms remain to be elucidated. The human keratinocyte cell line HaCaT was used to determine the effects of APS on psoriasis. Cells were randomly divided into five groups: i) Negative control group; ii) tumor necrosis factor (TNF)­α stimulated psoriasis model group; and iii) APS (20, 40 and 80 µg/ml) pretreated psoriasis groups. Cell viability and proliferation were investigated using the CCK­8 assay. ELISA and western blotting were applied to study the abundance of interleukin (IL)­8 and IL­12 in TNF­α­incubated culture medium and APS­treated HaCaT cells, respectively. In addition, the mRNA expression levels of p65, and the protein expression levels of nuclear factor (NF)­κB inhibitor­α (IκBα) and phosphorylated­p65, were detected by reverse transcription­quantitative polymerase chain reaction and western blotting, respectively. APS was revealed to significantly reduce TNF­α­stimulated elevation of HaCaT cell proliferation in a dose­dependent manner. The expression levels of inflammatory factors, including IL­8 and IL­12, were increased in response to TNF­α. In addition, the mRNA and protein expression levels of p65 were increased following treatment with TNF­α. Notably, treatment with APS was demonstrated to significantly attenuate the aforementioned effects in a dose­dependent manner. Furthermore, IκBα protein expression levels were significantly reduced following treatment with TNF­α, which was significantly reversed following treatment with APS. In conclusion, these results suggested that APS inhibited TNF­α­induced proliferation of keratinocytes and overactivation of the NF­κB signaling pathway.


Assuntos
Aloe/química , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Regulação da Expressão Gênica , Humanos , Mediadores da Inflamação/metabolismo , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , NF-kappa B/metabolismo , Extratos Vegetais/química , Polissacarídeos/química , Psoríase/genética , Psoríase/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia
8.
Biomed Pharmacother ; 90: 524-530, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28402921

RESUMO

MicroRNAs (miRNAs) have been demonstrated to contribute to malignant progression in psoriasis development. The purposes of the study was to evaluated the effects of miRNA-155 on cell proliferation, migration and apoptosis in psoriasis development via PTEN singaling pathway and identify its direct target protein. Quantitative real-time RT-PCR (qRT-PCR) was performed to examine the level of miR-155 in psoriasis cells, miR-155 was downregulated in a psoriasis cell line Hacat by transfected with small interfering RNA (siRNA), respectively. Cell survival was detected by the MTT assay and colony formation assay. Cell migration and invasion were measured via wound-healing assayand transwell assay. In addition, cell cycle and apoptosis about psoriasis cells was measured by flow cytometry. In this study, qRT-PCR assay showed that the expressions of miR-155 mRNA in psoriasis tissues were significantly higher than that in normal tissues. The assays about cell growth and proliferation showed that miR-155 knockdown led to a significant decrease in cell proliferation which was determined by MTT assay and colony formation assay compared to those of Lv-NC cells. Flow cytometry analysis showed that depletion of miR-155 could cause cell cycle change and the number of apoptotic cells was significantly increased in Lv-miR155 cells compared with control cells. In addition, the expression of several apoptosis-related factors were dramatically changed, such as PTEN, PIP3, AKT, p-AKT, Bax and Bcl-2. Our findings indicate that down-regulation of miR-155 significantly inhibits proliferation, migration, invasion and promotes apoptosis through PTEN singaling pathway in psoriasis cells. miR-155 might function as an oncogene miRNA in the progress of psoriasis.


Assuntos
Apoptose/genética , Proliferação de Células/genética , MicroRNAs/genética , PTEN Fosfo-Hidrolase/genética , Psoríase/genética , Transdução de Sinais/genética , Proteínas Reguladoras de Apoptose/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Sobrevivência Celular/genética , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Interferência de RNA/fisiologia , RNA Interferente Pequeno/genética
9.
Diagn Pathol ; 9: 171, 2014 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-25183455

RESUMO

BACKGROUND: miRNAs are involved in coordinating a variety of cellular processes by regulating their target genes. Aberrant expression of miRNAs is correlated with various cancers. Previous studies have shown that miR-337 is significantly down-regulated in pancreatic ductal adenocarcinoma (PDAC) and that its expression is negatively correlated to the expression of HOXB7. Both miR-337 and HOXB7 are associated with the prognosis of PDAC patients. The purpose of this study was to identify the molecular mechanisms by which miR-337 acts as a tumor suppressor in PDAC. METHODS: Synthetic miR-337 mimics were transfected into PANC-1 and As-PC-1 cells using Lipofectamine™ 2000. The expression of HOXB7 protein was analyzed by Western blot. Luciferase reporter plasmids were constructed to confirm that HOXB7 3'UTR was the target of miR-337. The effect of miR-337 on cell proliferation was evaluated by CCK8 assay and colony formation assay, and cell invasion was evaluated by wound healing assay and transwell assay. RESULTS: Western blot and luciferase activity assays identified HOXB7 as the target of miR-337. A CCK-8 assay showed the absorbance of cells transfected with miR-337 mimics to be less than that of control cells, and that the number of cell clones was significantly decreased by miR-337 expression. A wound healing assay showed the invasion rate of cells transfected with miR-337 mimics at 36 h to be markedly lower than in controls. The average number of cells penetrating the Matrigel was significantly lower than the controls. CONCLUSION: These findings suggest that miR-337 targets HOXB7 and effects significant suppression of PDAC cell proliferation and invasion. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_171.


Assuntos
Carcinoma Ductal Pancreático/genética , Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio/genética , MicroRNAs/genética , Neoplasias Pancreáticas/genética , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Proliferação de Células , Regulação para Baixo , Genes Reporter , Genes Supressores de Tumor , Humanos , Invasividade Neoplásica , Neoplasias Pancreáticas/patologia , Prognóstico , Transfecção
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(7): 1801-4, 2013 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-24059178

RESUMO

The objective of the present study was to investigate the feasibility of predicting chlorogenic acid, rutin, scopoletin and total polyphenol in tobacco by Fourier transform near-infrared (FT-NIR) spectroscopy. The partial least squares(PLS) regression method, second derivative and Norris derivative filter were applied in the NIR spectroscopy prediction of chlorogenic acid, rutin, scopoletin and total polyphenol in the range of 7 500 to 4 000 cm(-1). For chlorogenic acid, rutin, scopoletin and total polyphenol, the determination coefficients were 0.976 6, 0.941 9, 0.957 1 and 0.966 6, respectively. The SEP/SEC values for them were < 1.2, and the SD/SEP values for them were > 2. The root mean square error of cross validation (RMSECV) of the four calibration models were 1.938 9, 1.046 2, 0.047 9 and 2.745 2, respectively. NIR spectroscopy was compared with the conventional methods. The results show that the two methods showed no significant difference at the significant level of 0.05. NIR spectroscopy technology can accurately analyze chlorogenic acid, rutin, scopoletin and total polyphenol in tobacco.


Assuntos
Nicotiana/química , Polifenóis/análise , Rutina/análise , Escopoletina/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Ácido Clorogênico , Análise dos Mínimos Quadrados , Sensibilidade e Especificidade
11.
Photodermatol Photoimmunol Photomed ; 25(5): 264-9, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19747246

RESUMO

OBJECTIVE: Topical treatment of the specific inhibitor PD98059 (PD) for extracellular signal-regulated kinase (ERK)1/2 combined with ultraviolet B (UVB) exposure in an in vivo study was proposed to confirm the effectiveness of ERK1/2 involved in UVB-induced immunosuppression that was reversed by PD. METHODS: Based on the mouse model of local UVB-induced immunosuppression [UVB exposure, followed by sensitization with dinitrofluorobenzene (DNFB) on the abdomen skin before challenge on the ear site], the PD was applied on the abdomen-irradiated area 1 h, immediately before and 6 h after UVB exposure, respectively. The baseline of ear thickness was measured and remeasured 24 h after the challenge of DNFB for evaluation of ear-swelling response. Histopathologically, the ear biopsies were taken for hematoxylin and eosin staining. RESULTS: Mice that received PD post-irradiation treatment showed a statistically significant contact hypersensitivity compared with the UVB-irradiated mice (P<0.05), and paralleled with the biopsy showing a thickened epidermis with lymphocyte infiltration. Thus, the PD had abrogated the UV-induced local suppression of contact hypersensitivity. CONCLUSION: The ERK1/2 mitogen-activated protein kinase (MAPK) pathway plays an important role in the local UVB-induced immunosuppression, and its specific inhibitor PD can arrest its function, resulting in protection against UVB-induced immunosuppression in the present in vivo study.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Tolerância Imunológica/efeitos da radiação , Inibidores de Proteínas Quinases/farmacologia , Raios Ultravioleta , Animais , Cromatografia Líquida de Alta Pressão , Dinitrofluorbenzeno/administração & dosagem , Feminino , Camundongos , Camundongos Endogâmicos BALB C
12.
Appl Biochem Biotechnol ; 137-140(1-12): 115-30, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18478381

RESUMO

In this article, the mechanisms of thermoinactivation of glucose isomerase (GI) from Streptomyces rubiginosus (in soluble and immobilized forms) were investigated, particularly the contributions of thiol oxidation of the enzyme's cysteine residue and a "Maillard-like" reaction between the enzyme and sugars in high fructose corn syrup (HFCS). Soluble GI (SGI) was successfully immobilized on silica gel (13.5 microm particle size), with an activity yield between 20 and 40%. The immobilized GI (IGI) has high enzyme retention on the support during the glucose isomerization process. In batch reactors, SGI (half-life =145 h) was more stable than IGI (half-life =27 h) at 60 degrees C in HFCS, whereas at 80 degrees C, IGI (half-life =12 h) was more stable than SGI (half-life =5.2 h). IGI was subject to thiol oxidation at 60 degrees C, which contributed to the enzyme's deactivation. IGI was subject to thiol oxidation at 80 degrees C, but this did not contribute to the deactivation of the enzyme. SGI did not undergo thiol oxidation at 60 degrees C, but at 80 degrees C SGI underwent severe precipitation and thiol oxidation, which caused the enzyme to deactivate. Experimental results show that immobilization suppresses the destabilizing effect of thiol oxidation on GI. A "Maillard-like" reaction between SGI and the sugars also caused SGI thermoinactivation at 60, 70, and 80 degrees C, but had minimal effect on IGI. At 60 and 80 degrees C, IGI had higher thermostability in continuous reactors than in batch reactors, possibly because of reduced contact with deleterious compounds in HFCS.


Assuntos
Aldose-Cetose Isomerases/química , Streptomyces/enzimologia , Ativação Enzimática , Estabilidade Enzimática , Temperatura Alta , Desnaturação Proteica , Especificidade da Espécie , Streptomyces/classificação , Temperatura
13.
Am J Hypertens ; 18(12 Pt 1): 1606-13, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16364833

RESUMO

BACKGROUND: CGS 35601 is a potent triple vasopeptidase inhibitor (VPI) of angiotensin-converting enzyme (ACE), neutral endopeptidase (NEP), and endothelin-converting enzyme (ECE). The aim of the study was to determine the effects of this VPI on the hemodynamic profile of conscious, instrumented, unrestrained spontaneously hypertensive rats (SHR), in comparison to selective inhibitors of ACE and ACE + NEP, than +ECE combined. Circulating plasma concentrations of vasoactive mediators and reactive oxygen species were measured. METHODS: Old SHR male were instrumented (arterial catheter) and placed in a metabolic cage for daily hemodynamic measurements and blood samplings. Seven days after surgery, SHR received 1) saline vehicle; 2) increasing doses of the triple CGS 35601 (0.01, 0.1, 1, and 5 mg/kg/d, intra-arterially (i.a.) infusion for 5 d/dose) followed by a 5-day washout period; 3) benazepril (ACE inhibitor), ACE inhibitor + CGS 24592 (NEP inhibitor) and ACE inhibitor + NEP inhibitor + CGS 35066 (ECE inhibitor) (1 or 5 mg/kg/d i.a. infusion for 5 d/combination) followed by a 5-day washout period. RESULTS: The lowest dose of CGS 35601 had no effect. Doses at 0.1, 1, and 5 mg/kg/d reduced mean arterial blood pressure by 10%, 22%, and 40%, respectively. Heart rate was unaffected in all groups. CGS 35601 decreased concentrations of angiotensin II (Ang II), endothelin-1 (ET-1), and pro-atrial natriuretic peptide (proANP), and increased those of big ET-1, atrial natriuretic peptide (ANP), bradykinin (BK), and hydrogen peroxide (H2O2) dose dependently. CONCLUSIONS: The blood pressure-lowering effect of this triple VPI was superior to that of the other VPI in this preclinical rat model of hypertension. Further experiments are needed to assess triple VPI to other combinations in other models with regard to efficacy and angioedema. Only then it may constitute a first-in-class approach for the treatment of hypertension and other cardiovascular disorders.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Indóis/farmacologia , Inibidores de Proteases/farmacologia , Angiotensina II/sangue , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Fator Natriurético Atrial/sangue , Benzazepinas/administração & dosagem , Benzazepinas/farmacologia , Benzofuranos/administração & dosagem , Benzofuranos/farmacologia , Relação Dose-Resposta a Droga , Endotelina-1/sangue , Enzimas Conversoras de Endotelina , Hipertensão/sangue , Hipertensão/tratamento farmacológico , Hipertensão/metabolismo , Masculino , Metaloendopeptidases/antagonistas & inibidores , Neprilisina/antagonistas & inibidores , Óxido Nítrico/metabolismo , Organofosfonatos/administração & dosagem , Organofosfonatos/farmacologia , Fenilalanina/administração & dosagem , Fenilalanina/análogos & derivados , Fenilalanina/farmacologia , Inibidores de Proteases/administração & dosagem , Inibidores de Proteases/farmacocinética , Ratos , Ratos Endogâmicos SHR , Ratos Sprague-Dawley , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo
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