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1.
J Ethnopharmacol ; 330: 118226, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-38670401

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Idiopathic pulmonary fibrosis (IPF) is a progressive fibrosing pulmonary disorder that has a poor prognosis and high mortality. Although there has been extensive effort to introduce several new anti-fibrotic agents in the past decade, IPF remains an incurable disease. Mimosa pudica L., an indigenous Vietnamese plant, has been empirically used to treat respiratory disorders. Nevertheless, the therapeutic effects of M. pudica (MP) on lung fibrosis and the mechanisms underlying those effects remain unclear. AIM OF THE STUDY: This study investigated the protective effect of a crude ethanol extract of the above-ground parts of MP against pulmonary fibrogenesis. MATERIALS AND METHODS: Inflammatory responses triggered by TNFα in structural lung cells were examined in normal human lung fibroblasts and A549 alveolar epithelial cells using Western blot analysis, reverse transcription-quantitative polymerase chain reaction assays, and immunocytochemistry. The epithelial-to-mesenchymal transition (EMT) was examined via cell morphology observations, F-actin fluorescent staining, gene and protein expression measurements, and a wound-healing assay. Anti-fibrotic assays including collagen release, differentiation, and measurements of fibrosis-related gene and protein expression levels were performed on TGFß-stimulated human lung fibroblasts and lung fibroblasts derived from mice with fibrotic lungs. Finally, in vitro anti-fibrotic activities were validated using a mouse model of bleomycin-induced pulmonary fibrosis. RESULTS: MP alleviated the inflammatory responses of A549 alveolar epithelial cells and lung fibroblasts, as revealed by inhibition of TNFα-induced chemotactic cytokine and chemokine expression, along with inactivation of the MAPK and NFκB signalling pathways. MP also partially reversed the TGFß-promoted EMT via downregulation of mesenchymal markers in A549 cells. Importantly, MP decreased the expression levels of fibrosis-related genes/proteins including collagen I, fibronectin, and αSMA; moreover, it suppressed collagen secretion and prevented myofibroblast differentiation in lung fibroblasts. These effects were mediated by FOXO3 stabilization through suppression of TGFß-induced ERK1/2 phosphorylation. MP consistently protected mice from the onset and progression of bleomycin-induced pulmonary fibrosis. CONCLUSION: This study explored the multifaceted roles of MP in counteracting the pathobiological processes of lung fibrosis. The results suggest that further evaluation of MP could yield candidate therapies for IPF.


Assuntos
Transição Epitelial-Mesenquimal , Proteína Forkhead Box O3 , Sistema de Sinalização das MAP Quinases , Extratos Vegetais , Fibrose Pulmonar , Animais , Humanos , Masculino , Camundongos , Células A549 , Antifibróticos/farmacologia , Bleomicina , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Proteína Forkhead Box O3/metabolismo , Fibrose Pulmonar Idiopática/tratamento farmacológico , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/patologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/induzido quimicamente
2.
Nat Commun ; 14(1): 7593, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37989731

RESUMO

The HIV-1 fusion peptide (FP) represents a promising vaccine target, but global FP sequence diversity among circulating strains has limited anti-FP antibodies to ~60% neutralization breadth. Here we evolve the FP-targeting antibody VRC34.01 in vitro to enhance FP-neutralization using site saturation mutagenesis and yeast display. Successive rounds of directed evolution by iterative selection of antibodies for binding to resistant HIV-1 strains establish a variant, VRC34.01_mm28, as a best-in-class antibody with 10-fold enhanced potency compared to the template antibody and ~80% breadth on a cross-clade 208-strain neutralization panel. Structural analyses demonstrate that the improved paratope expands the FP binding groove to accommodate diverse FP sequences of different lengths while also recognizing the HIV-1 Env backbone. These data reveal critical antibody features for enhanced neutralization breadth and potency against the FP site of vulnerability and accelerate clinical development of broad HIV-1 FP-targeting vaccines and therapeutics.


Assuntos
Infecções por HIV , HIV-1 , Humanos , HIV-1/genética , Anticorpos Anti-HIV , Anticorpos Neutralizantes , Peptídeos , Sequência de Aminoácidos , Vacinas de Subunidades Antigênicas , Testes de Neutralização , Produtos do Gene env do Vírus da Imunodeficiência Humana
3.
Sci Total Environ ; 904: 166330, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37591389

RESUMO

Although sediments are considered to be a major sink for microplastics (MP), there is still a relative lack of knowledge on the factors that influence the occurrence and abundance of MP in riverine sediments. The present study investigated the occurrence and distribution of MP in riverine sediments collected at twelve sites representative of different populated and urbanized rivers (To Lich, Nhue and Day Rivers) located in the Red River Delta (RRD, Vietnam, during dry and rainy seasons. MP concentrations ranged from 1600 items kg-1 dw to 94,300 items kg-1dw. Fiber shape dominated and MP were made of polypropylene (PP) and polyethylene (PE) predominantly. An absence of seasonal effect was observed for both fragments and fibers for each rivers. Decreasing MP concentrations trend was evidenced from the To Lich River, to the Nhue River and to the Day River, coupled with a decreasing fiber length and an increasing fragment area in the surface sediment from upstream to downstream. Content of organic matter was correlated to MP concentrations suggesting that, high levels of organic matter could be MP hotspots in urban rivers. Also, high population density as well as in highly residential areas are related to higher MP concentrations in sediments. Finally, a MP high ecological risk (RI: 866 to 4711) was calculated in the RDD.

4.
Heliyon ; 8(3): e09070, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35287327

RESUMO

Balanophora laxiflora, a medicinal plant traditionally used to treat fever, pain, and inflammation in Vietnam, has been reported to possess prominent anti-inflammatory activity. This study examined the active constituents and molecular mechanisms underlying these anti-inflammatory effects using bioactivity-guided isolation in combination with cell-based assays and animal models of inflammation. Among the isolated compounds, the triterpenoid (21α)-22-hydroxyhopan-3-one (1) showed the most potent inhibitory effect on COX-2 expression in LPS-stimulated Raw 264.7 macrophages. Furthermore, 1 suppressed the expression of the inflammatory mediators iNOS, IL-1ß, INFß, and TNFα in activated Raw 264.7 macrophages and alleviated the inflammatory response in carrageenan-induced paw oedema and a cotton pellet-induced granuloma model. Mechanistically, the anti-inflammatory effects of 1 were mediated via decreasing cellular reactive oxygen species (ROS) levels by inhibiting NADPH oxidases (NOXs) and free radical scavenging activities. By downregulating ROS signalling, 1 reduced the activation of MAPK signalling pathways, leading to decreased AP-1-dependent transcription of inflammatory mediators. These findings shed light on the chemical constituents that contribute to the anti-inflammatory actions of B. laxiflora and suggest that 1 is a promising candidate for treating inflammation-related diseases.

5.
Bioorg Med Chem Lett ; 31: 127673, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33161122

RESUMO

Cassaine diterpenoids as erythrofordins A-C (1-3), pseudo-erythrosuamin (4), and erythrofordin U (5) isolated from the leaves of Vietnamese Erythrophleum fordii Oliver were tested cytotoxic activity against human leukemia cancer cells. The results showed that these metabolites exhibited dose-dependent cytotoxicity against human leukemia HL-60 and KG cells with IC50 values ranging from 15.2 ± 1.5 to 42.2 ± 3.6 µM. Treatment with erythrofordin B led to the apoptosis of HL-60 and KG cells due to the activation of caspase 3, caspase 9, and poly (ADP-ribose) polymerase (PARP). Erythrofordin B significantly increased Bak protein expression, but downregulated the anti-apoptotic protein Bcl-2, in HL-60 cells. In silico results demonstrated that erythrofordin B can bind to both the procaspase-3 allosteric site and the PARP-1 active site, with binding energies of -7.36 and -10.76 kcal/mol, respectively. These results indicated that the leaves of Vietnamese E. fordii, which contain cassaine diterpenoids, can induce the apoptosis of human leukemia cancer cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Fabaceae/química , Extratos Vegetais/farmacologia , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Poli(ADP-Ribose) Polimerase-1/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/química , Inibidores de Poli(ADP-Ribose) Polimerases/isolamento & purificação , Relação Estrutura-Atividade
6.
Curr Alzheimer Res ; 16(4): 333-343, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30873921

RESUMO

BACKGROUND: Based on the prevalence studies, the number of people suffering from dementia will almost double every 20 years, to 65.7 million in 2030 and 115.4 million in 2050, assuming no changes in mortality, effective preventative measures, definitive diagnostic guidelines or curative treatment. From the abovementioned epidemiological data, it is obvious that dementia constitutes a major public health problem not only at present, but unfortunately also in the future. OBJECTIVES AND METHODS: Several N-alkylated tacrine (THA) derivatives have already been synthesized by Pomponi et al., in 1997. However, these compounds were tested for their anti-AChE activity using enzyme isolated from Electrophorus electricus. For this reason, we have decided to extend the previously reported series of THA derivatives and consequently test them in the battery of experiments, the results of which have served to more relevant evaluation of these compounds from the perspective of Alzeimer´s disease compared to that published by Pomponi. RESULTS AND CONCLUSION: In summary, all compounds of interest effectively inhibited ChEs in vitro. One of the most promising derivatives 8 bearing an N-octyl chain showed 2.5-fold higher AChE inhibitory activity in relation to tacrine. With respect to blood-brain barrier (BBB) penetration, it can be claimed that synthesized analogues are presumably able to cross the BBB. From the point of view of hepatotoxicity, selected Nalkylated tacrine derivatives exerted worse results compared to tacrine. However, in vitro results are only illustrative, therefore, only in vivo experiments could determine the real value of selected N-alkylated THA derivatives.


Assuntos
Doença de Alzheimer , Inibidores da Colinesterase/farmacologia , Descoberta de Drogas , Tacrina/análogos & derivados , Tacrina/farmacologia , Células Hep G2 , Humanos
7.
Int J Mol Sci ; 18(7)2017 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-28686210

RESUMO

The management of severe acetabular bone defects in revision reconstructive orthopedic surgery is challenging. In this study, cyclic precalcification (CP) treatment was used on both nanotube-surface Ti-mesh and a bone graft substitute for the acetabular defect model, and its effects were assessed in vitro and in vivo. Nanotube-Ti mesh coated with hydroxyapatite/ß-tricalcium phosphate (HA/ß-TCP) was manufactured by an anodizing and a sintering method, respectively. An 8 mm diameter defect was created on each acetabulum of eight rabbits, then treated by grafting materials and covered by Ti meshes. At four and eight weeks, postoperatively, biopsies were performed for histomorphometric analyses. The newly-formed bone layers under cyclic precalcified anodized Ti (CP-AT) meshes were superior with regard to the mineralized area at both four and eight weeks, as compared with that under untreated Ti meshes. Active bone regeneration at 2-4 weeks was stronger than at 6-8 weeks, particularly with treated biphasic ceramic (p < 0.05). CP improved the bioactivity of Ti meshes and biphasic grafting materials. Moreover, the precalcified nanotubular Ti meshes could enhance early contact bone formation on the mesh and, therefore, may reduce the collapse of Ti meshes into the defect, increasing the sufficiency of acetabular reconstruction. Finally, cyclic precalcification did not affect bone regeneration by biphasic grafting materials in vivo.


Assuntos
Acetábulo/patologia , Hidroxiapatitas/farmacologia , Nanotubos/química , Titânio/farmacologia , Animais , Calcificação Fisiológica/efeitos dos fármacos , Cerâmica/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Masculino , Nanotubos/ultraestrutura , Coelhos , Cicatrização/efeitos dos fármacos
8.
Am J Med Genet A ; 146A(12): 1530-42, 2008 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-18478590

RESUMO

Mutations in the LMNA gene result in diverse phenotypes including Emery Dreifuss muscular dystrophy, limb girdle muscular dystrophy, dilated cardiomyopathy with conduction system disease, Dunnigan type familial partial lipodystrophy, mandibulo acral dysplasia, Hutchinson Gilford progeria syndrome, restrictive dermopathy and autosomal recessive Charcot Marie Tooth type 2. The c.1930C > T (R644C) missense mutation has previously been reported in eight unrelated patients with variable features including left ventricular hypertrophy, limb girdle muscle weakness, dilated cardiomyopathy and atypical progeria. Here we report on the details of nine additional patients in eight families with this mutation. Patients 1 and 2 presented with lipodystrophy and insulin resistance, Patient 1 having in addition focal segmental glomerulosclerosis. Patient 3 presented with motor neuropathy, Patient 4 with arthrogryposis and dilated cardiomyopathy with left ventricular non-compaction, Patient 5 with severe scoliosis and contractures, Patient 6 with limb girdle weakness and Patient 7 with hepatic steatosis and insulin resistance. Patients 8 and 9 are brothers with proximal weakness and contractures. Nonpenetrance was observed frequently in first degree relatives. This report provides further evidence of the extreme phenotypic diversity and low penetrance associated with the R644C mutation. Possible explanations for these observations are discussed.


Assuntos
Doenças Genéticas Inatas , Lamina Tipo A/genética , Mutação de Sentido Incorreto , Fenótipo , Adolescente , Adulto , Substituição de Aminoácidos/genética , Arginina/genética , Criança , Cisteína/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Penetrância
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