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1.
Neoplasma ; 69(4): 931-939, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35652620

RESUMO

Natural killer (NK) cells typically function as frontline lymphocytes against cancer although little is known about their engagement in non-small cell lung cancer (NSCLC). This study compared the performance and activity of NK cells and their subsets in the peripheral blood of NSCLC sufferers and healthy participants. In total, 67 healthy controls (40 males; 59.7%) and 56 patients with NSCLC (35 males; 62.5%) were included (mean age, 66.6 years). Flow cytometry identified NK cells and their subpopulations in external blood, and the total number, proportion, activity, surface activating, and inhibitory receptor expression levels were determined. Results showed that NK cell surface receptors CD107a, IFN-γ, and TNF-α activity were markedly reduced in lung cancer patients compared to healthy controls. The number and ratio of NK cells within the lymphocyte population were decreased in patients. The concentration of the inhibitory receptors TIGIT, TIM-3, CD96, PD-1, and Siglec-7 were increased in patients, whereas the expression level of the activating receptor NKP30 was decreased. Moreover, the expression levels of IFN-γ, TIGIT, CD96, PD-1, and TIM-3 were correlated with the clinical phase of NSCLC. These findings suggest that surface receptors from NK cells are likely to be involved in the evolution of NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Idoso , Antígenos CD/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Humanos , Células Matadoras Naturais , Neoplasias Pulmonares/metabolismo , Masculino , Receptor de Morte Celular Programada 1/metabolismo , Receptores Imunológicos/metabolismo
2.
J Asian Nat Prod Res ; 22(2): 144-152, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30526081

RESUMO

Two oleanane-type triterpenoid saponins named pedunsaponin D (1) and pedunsaponin E (2) were isolated from the roots of Pueraria peduncularis. The structures of the new compounds were elucidated based on chemical and physicochemical evidence as follows: pedunsaponin D, 3-O-ß-glucopyranosyl-(1-3)-ß-glucuronopyranosyl-3ß,15α,23α-trihydroxy-11,13(18)-oleanadien-16-one (1); pedunsaponin E, 3-O-ß-glucopyranosyl-(1-2)-ß-glucopy ranosyl(1-2)[ß-glucopyranosyl(1-3)-ß-glucuronopyranosyl]-3ß-hydroxy-16-oxoolean-12-en-30-oic acid (2). The two compounds showed moderate molluscicidal activity.[Formula: see text].


Assuntos
Pueraria , Saponinas , Triterpenos , Estrutura Molecular , Raízes de Plantas
3.
Acta Pharmacol Sin ; 40(8): 1049-1057, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30728467

RESUMO

Second-generation antipsychotic drug (SGA)-induced metabolic abnormalities, such as dyslipidemia, are a major clinical problem for antipsychotic therapy. Accumulated evidences have shown the efficacy of statins in reducing SGA-induced dyslipidemia, but the underlying mechanisms are unclear. In this study, we explored whether mTOR signaling was involved in olanzapine (OLZ)-induced dyslipidemia as well as the lipid-lowering effects of cotreatment of simvastatin (Sim) in rats. Model rats received OLZ (1.0 mg/kg, t.i.d.) for 7 weeks; from the third week a group of model rats were cotreatment of Sim (3.0 mg/kg, t.i.d.) for 5 weeks. We found that OLZ treatment significantly increased the plasma triglyceride (TG) and total cholesterol (TC) levels, and promoted lipid accumulation in the liver, whereas cotreatment of Sim reversed OLZ-induced dyslipidemia. Hepatic mTORC1 and p-mTORC1 expression was accelerated in the OLZ treatment group, with upregulation of mRNA expression of sterol regulatory element-binding protein 1c (SREBP1c) and its target genes, whereas these alterations were ameliorated by Sim cotreatment. In HepG2 cells, rapamycin (a mTOR inhibitor) significantly reduced the OLZ-stimulated hepatocellular lipid contents and weakened the ability of Sim to lower lipids via a mechanism associated with the upregulation of SREBP1c-mediated de novo lipogenesis. Our data suggest that OLZ induces lipid accumulation in both plasma and liver, and Sim ameliorates OLZ-induced lipid metabolic dysfunction through its effects on mTOR signaling via reducing SREBP1c activation and the downregulation of gene expression involved in lipogenesis. These data provide a new insight into the prevention of metabolic side effects induced by antipsychotic drugs.


Assuntos
Dislipidemias/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Sinvastatina/uso terapêutico , Serina-Treonina Quinases TOR/metabolismo , Animais , Regulação para Baixo , Dislipidemias/induzido quimicamente , Fígado Gorduroso/induzido quimicamente , Fígado Gorduroso/tratamento farmacológico , Feminino , Células Hep G2 , Humanos , Lipogênese/efeitos dos fármacos , Lipogênese/genética , Fígado/patologia , Olanzapina , Ratos Sprague-Dawley , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
4.
J Toxicol Environ Health A ; 80(22): 1212-1221, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28910587

RESUMO

Trichosanthin (TCS), isolated from the root tuber of Trichosantheskirilowii, a well-known traditional Chinese medicinal plant, belonging to the Cucurbitaceae family, was found to exhibit numerous biological and pharmacological activities including anti-inflammatory. However, the effects of TCS on arterial injury induced neointimal hyperplasia and inflammatory cell infiltration remains poorly understood. The aim of study was to examine the effectiveness of TCS on arterial injury-mediated inflammatory processes and underlying mechanisms. A balloon-injured carotid artery induced injury in vivo in rats was established as a model of vascular injury. After 1 day TCS at 20, 40, or 80 mg/kg/day was administered intraperitoneally, daily for 14 days. Subsequently, the carotid artery was excised and taken for immunohistochemical staining. Data showed that TCS significantly dose-dependently reduced balloon injury-induced neointima formation in the carotid artery model rat, accompanied by markedly decreased positive expression percentage proliferating cell nuclear antigen (PCNA). In the in vitro study vascular smooth muscle cells (VSMC) were cultured, proliferation stimulated with platelet-derived growth factor-BB (PDGF-BB) (20 ng/ml) and TCS at 1, 2, or 4 µM added. Data demonstrated that TCS inhibited proliferation and cell cycle progression of VSMC induced by PDGF-BB. Further, TCS significantly lowered mRNA expression of cyclinD1, cyclinE1, and c-fos, and protein expression levels of Akt1, Akt2, and mitogen-activated protein kinase MAPK (ERK1) signaling pathway mediated by PDGF-BB. These findings indicate that TCS inhibits vascular neointimal hyperplasia induced by vascular injury in rats by suppression of VSMC proliferation and migration, which may involve inhibition of Akt/MAPK/ERK signal pathway.


Assuntos
Hiperplasia/tratamento farmacológico , Neointima/tratamento farmacológico , Tricosantina/farmacologia , Tricosantina/uso terapêutico , Lesões do Sistema Vascular/tratamento farmacológico , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Catéteres/efeitos adversos , Hiperplasia/etiologia , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Lesões do Sistema Vascular/etiologia
5.
Tohoku J Exp Med ; 236(2): 155-62, 2015 06.
Artigo em Inglês | MEDLINE | ID: mdl-26074502

RESUMO

Pulmonary hypertension (PH) is a life-threatening disease that is characterized by elevated pulmonary blood pressure, abnormally thickened pulmonary arteries, and right ventricular hypertrophy. Monocrotaline (MCT) has been used to generate an experimental model of PH in rats, with PH initiated from injuries of lung vascular endothelium. Salvia Miltiorrhiza Bge.f.alba is a widely used traditional herb in China, known to exert protective effects on vascular endothelial cell injury in animal experiments. However, the role of Salvia Miltiorrhiza Bge.f.alba in PH remains unclear. Thus, we investigated the effects of the aqueous extract of Salvia Miltiorrhiza Bge.f.alba (AESM) on MCT-induced PH and explored the pertinent mechanism. PH was induced in rats by a single subcutaneous injection of MCT (60 mg/kg body weight). Low or high dose (4.6 g/kg or 14 g/kg body weight) of AESM was then administered orally for 21 days to PH rats. Hemodynamic study showed that AESM reduced mean pulmonary artery pressure and improved right ventricle function. Lung pathological analysis revealed that AESM reduced wall thickness and lumen stenosis of pulmonary vessels. Also AESM ameliorated right ventricular hypertrophy. Measurement of biochemical parameters indicated that AESM decreased endothelin-1 and thromboxane A2 in plasma and increased nitrogen monoxide and prostacyclin in the plasma and reduced the increase of transforming growth factor ß1 in lung tissue. Our results suggest that AESM may ameliorate the progression of MCT-induced PH in rats, at least in part by its protective effect on endothelial injury. Therefore, Salvia Miltiorrhiza Bge.f.alba could be useful in the treatment of PH.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/prevenção & controle , Monocrotalina , Extratos Vegetais/uso terapêutico , Venenos , Salvia miltiorrhiza/química , Animais , Endotelina-1/metabolismo , Hemodinâmica/efeitos dos fármacos , Masculino , Óxido Nítrico/sangue , Prostaglandinas I/sangue , Ratos , Ratos Sprague-Dawley , Tromboxano A2/metabolismo , Fator de Crescimento Transformador beta1/sangue , Função Ventricular Direita/efeitos dos fármacos
6.
Heart Lung Circ ; 24(6): 602-10, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25533677

RESUMO

BACKGROUND: Infusion with hydrogen gas-saturated saline has recently been reported to exert antioxidant and anti-inflammatory activity that may protect against organ damage induced by oxidative stress. Therefore because oxidative stress plays a significant role in the pathophysiology of myocardial infarction (MI), the aim of our study was to investigate whether hydrogen-rich saline has cardioprotective effects against isoproterenol-induced MI in rats. METHODS: An acute MI model was induced in male Wistar rats by subcutaneous injection of isoproterenol. Different doses of hydrogen-rich saline (5, 7.5, and 10 mL/kg body weight i.p.) or Vitamin C (250 mg/kg body weight i.g.) were administered to the rats. Oxidative stress indices including levels of myocardial marker enzymes, inflammatory cytokines, membrane-bound myocardial enzymes and histopathological changes were measured. RESULTS: Compared with those in isoproterenol-MI group, hydrogen-rich saline decreased malondialdehyde and 8-hydroxy-desoxyguanosine concentrations, enhanced superoxide dismutase and Na(+)-K(+)-ATPase activity, lowered Ca(2+)-ATPase activity and decreased interleukin-6 and tumour necrosis factor-α levels in the serum and/or cardiac tissue of rats. Hydrogen-rich saline pretreatment also diminished infarct size, improved left heart function, and ameliorated pathological changes of the left heart. CONCLUSION: From these results, hydrogen-rich saline exerts cardiovascular protective effects against isoproterenol-induced MI at least in part via interactions which evoke antioxidant and anti-inflammatory activities.


Assuntos
Cardiotônicos/farmacologia , Hidrogênio/farmacologia , Isoproterenol/farmacologia , Infarto do Miocárdio/patologia , Cloreto de Sódio/farmacologia , Análise de Variância , Animais , Biomarcadores/sangue , Biópsia por Agulha , Citocinas/sangue , Modelos Animais de Doenças , Combinação de Medicamentos , Imuno-Histoquímica , Interleucina-6/sangue , Masculino , Infarto do Miocárdio/induzido quimicamente , Estresse Oxidativo , Distribuição Aleatória , Ratos , Ratos Wistar , Valores de Referência , Fator de Necrose Tumoral alfa/sangue
7.
Psychopharmacology (Berl) ; 239(3): 851-865, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35103832

RESUMO

RATIONALE: Mitochondrial fragmentation contributes to the initiation of Alzheimer's disease (AD) pathology. Baicalin plays a significant role in rescuing mitochondrial dysfunction. However, the effect of baicalin treatment on the modulation of mitochondrial fragmentation has not yet been assessed. OBJECTIVES: The present study was designed to evaluate the effect of baicalin on memory and understand its mechanism of action. RESULTS: Baicalin treatment significantly reversed the altered learning and memory behaviours in AD mouse model. We found that baicalin treatment significantly improved the levels of microtubule association protein-2 and enhanced the expression of synaptophysin and postsynaptic density protein 95 (PSD95). Moreover, treatment with baicalin reversed amyloid-ß oligomer (AßO)-induced abnormalities in the succinate dehydrogenase complex iron sulphur subunit B (SDHB) and cytochrome c oxidase components I (COXI) and mitochondrial fragmentation in the hippocampus. Further, we found that baicalin decreased the PDE4 levels and upregulated the levels of phosphorylated Ser157 site of vasodilator-stimulated phosphoprotein (pVASPs157) and phosphorylated Ser637 site of mitochondrial dynamin-related protein 1 (pDrp1S637). Moreover, in AßO-treated HT-22 cells, H89 inhibited the effect of baicalin on PSD95, mitochondrial fragmentation, SDHB and COXI, PDE4, pVASPs157, and pDrp1S637. CONCLUSION: The effect of baicalin on memory improvement may be due to improved synaptic plasticity, mitochondrial fragmentation, and rescue of dysfunction via the inhibition of PDE4, which leads to activation of pDrp1S637 in the AßO-induced model.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Flavonoides , Transtornos da Memória/metabolismo , Camundongos , Mitocôndrias , Neurônios
8.
Respir Res ; 12: 26, 2011 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-21375753

RESUMO

BACKGROUND: Hydrogen-rich saline has been reported to have antioxidant and anti-inflammatory effects and effectively protect against organ damage. Oxidative stress and inflammation contribute to the pathogenesis and/or development of pulmonary hypertension. In this study, we investigated the effects of hydrogen-rich saline on the prevention of pulmonary hypertension induced by monocrotaline in a rat model. METHODS: In male Sprague-Dawley rats, pulmonary hypertension was induced by subcutaneous administration of monocrotaline at a concentration of 6 mg/100 g body weight. Hydrogen-rich saline (5 ml/kg) or saline was administered intraperitoneally once daily for 2 or 3 weeks. Severity of pulmonary hypertension was assessed by hemodynamic index and histologic analysis. Malondialdehyde and 8-hydroxy-desoxyguanosine level, and superoxide dismutase activity were measured in the lung tissue and serum. Levels of pro-inflammatory cytokines (tumor necrosis factor-α, interleukin-6) in serum were determined with enzyme-linked immunosorbent assay. RESULTS: Hydrogen-rich saline treatment improved hemodynamics and reversed right ventricular hypertrophy. It also decreased malondialdehyde and 8-hydroxy-desoxyguanosine levels, and increased superoxide dismutase activity in the lung tissue and serum, accompanied by a decrease in pro-inflammatory cytokines. CONCLUSIONS: These results suggest that hydrogen-rich saline ameliorates the progression of pulmonary hypertension induced by monocrotaline in rats, which may be associated with its antioxidant and anti-inflammatory effects.


Assuntos
Anti-Inflamatórios/farmacologia , Anti-Hipertensivos/farmacologia , Antioxidantes/farmacologia , Hipertensão Pulmonar/prevenção & controle , Cloreto de Sódio/farmacologia , 8-Hidroxi-2'-Desoxiguanosina , Animais , Biomarcadores/sangue , Pressão Sanguínea/efeitos dos fármacos , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Ensaio de Imunoadsorção Enzimática , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/fisiopatologia , Hipertrofia Ventricular Direita/prevenção & controle , Mediadores da Inflamação/sangue , Interleucina-6/sangue , Masculino , Malondialdeído/sangue , Monocrotalina , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/sangue , Fatores de Tempo , Fator de Necrose Tumoral alfa/sangue
9.
Sheng Li Ke Xue Jin Zhan ; 42(1): 33-8, 2011 Feb.
Artigo em Zh | MEDLINE | ID: mdl-21595185

RESUMO

Most platelet-derived oxidants are produced through NAD (P) H-oxidase enzyme system. There are antioxidants such as superoxide dismutase and reduced glutathione in platelet. Oxidative stress alters platelet functions via regulation of platelet aggregation phase, impact on platelet nitric oxide and alpha II bbeta3 integrin, and imbalance between reduced and oxidized glutathione in platelet. Activated platelet by oxidative stress can influence blood vessel endothelium cell function, and worsen atherosclerosis through CD40 ligand. LDL is modified to oxidized LDL by platelets which can trigger foam cell formation. Some drugs with therapeutic intervention to reduce oxidative stress of platelet will be of use for atherosclerosis treatment.


Assuntos
Aterosclerose/fisiopatologia , Plaquetas/fisiologia , Estresse Oxidativo/fisiologia , Agregação Plaquetária/fisiologia , Animais , Plaquetas/metabolismo , Células Endoteliais/fisiologia , Humanos , Superóxido Dismutase/metabolismo
10.
Ying Yong Sheng Tai Xue Bao ; 31(3): 863-871, 2020 Mar.
Artigo em Zh | MEDLINE | ID: mdl-32537982

RESUMO

Soil spectral information differ across different land use types. Understanding the appropriate modeling methods for different land use types can efficiently and accurately invert soil organic carbon content. We collected 248 samples from forest, cultivated land and orchard in the north-central part of Fengxin County, Jiangxi Province. First, original spectral reflectance curves were reduced noises with Savitzky-Golay (SG) filter. Then 10 nm resampling method was used to reduce data redundancy. We used partial least squares regression (PLSR), support vector machine regression based on grid search method (GRID-SVR) and support vector machine regression based on particle swarm optimization (PSO-SVR) to construct the inversion models of soil organic carbon content. The results showed that when constructing a single land-use type inversion model, RPD of the PLSR method for forest, cultivated land and orchard was 1.536, 1.315 and 1.493 respectively. RPD of GRID-SVR method increased 0.150, 0.183 and 0.502 than that of PLSR method, respectively. The PSO-SVR method had higher accuracy, with RPD being 20.8%, 10.0% and 2.7% higher than GRID-SVR for forest, cultivated land and orchard, respectively. The RPD of forest and orchard were 2.036 and 2.049, which well predicts soil organic carbon. The RPD of cultivated land was 1.647, which can make a rough estimate of soil organic carbon. The PSO-SVR model had the best prediction effect on soil organic carbon of different land use types, with the prediction accuracy of soil organic carbon content in forest and orchard being close and higher than cultivated land. Soil nutrition diffed acorss different land use types, which affect the prediction of soil organic carbon content. Models for inversion of soil organic carbon should be constructed separately for different land use types.


Assuntos
Carbono , Solo , China , Florestas , Análise dos Mínimos Quadrados
11.
Environ Sci Pollut Res Int ; 27(24): 30390-30404, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32462617

RESUMO

Yingtan is a rapidly urbanizing city in Jiangxi Province, South China. During rapid urbanization, construction land is expanded at the expense of cropland and forest. Although economic benefits are gained, ecological and environmental damage is irreversible. In this study, a methodological framework for land use simulation using an integrated genetic algorithm-cellular automata-Markov model is proposed to assess the relationship between economic development and cropland protection in Yingtan. This framework considers both the economic and ecological benefits of different land use types. Three land use scenarios are evaluated to seek recommendations for land use practice. The results show that the areas with high suitability for cropland and construction are mainly concentrated in urban fringes. Under the green development scenario, the area of new construction land can meet the land demand for population growth and economic development proposed for 2025 based on population forecasting and government interviews. The expansion for construction land is decreased by ~ 35 km2 while the cropland area is increased by ~ 20 km2 compared with those under natural and controlled development scenarios. Additionally, ecological losses are lowest under the green development scenario. In conclusion, the green development scenario is conducive to both cropland and ecological protection, which is of relevance for future spatial planning in Yingtan.


Assuntos
Conservação dos Recursos Naturais , Urbanização , Algoritmos , China , Cidades , Ecossistema
12.
Ying Yong Sheng Tai Xue Bao ; 31(1): 208-218, 2020 Jan.
Artigo em Zh | MEDLINE | ID: mdl-31957398

RESUMO

The rational delimitation of urban development boundary plays an important role in guiding the orderly growth of urban space and ensure proper environment health of urban space. In this study, we evaluated the ecological sensitivity of Nanchang City from four aspects (soil erosion, habitat, geological disaster and water resource) and simulated urban expansion in 2020 based on CA-Markov and land use data in 2000, 2010 and 2015. Spatial decision-making analysis of the two aspects was carried out in combination to the future development of the study area. We proposed a new method of delimitating urban development boundary integrating environmental protection and urban development through the dynamic coordination of both aspects. The results showed that ecological sensitivity of Nanchang City was moderate. The scale of urban construction land based on CA Markov simulation was 1239.67 km2, which slightly exceeded the planned construction land target (1201.65 km2). When the dynamic adjustment was done by superimposing the ecological sensitivity evaluation results with the expansion simulation results, the adjusted construction land scale of Nanchang City was 1193.15 km2, which met the planned requirement. Consideration of the coordination of protection and development could not only protect the ecological space, but also help to guide the orderly growth of urban space and ensure the healthy development of urban space, and thus was an important way to achieve a win-win situation between rational urban development and ecological protection.


Assuntos
Ecologia , Reforma Urbana , China , Cidades , Conservação dos Recursos Naturais , Ecossistema
13.
Ying Yong Sheng Tai Xue Bao ; 30(2): 627-636, 2019 Feb 20.
Artigo em Zh | MEDLINE | ID: mdl-30915815

RESUMO

Land carrying capacity is one of the important research fields for land management and sustainable use. Urban-rural construction land is an essential component of land use type, the rationality of whose structure and layout is crucial to the sustainable use of land. Here, we executed the evaluation of the suitability of urban-rural construction land development, accounted the bearable critical threshold of urban-rural construction land, calculated the bearable abundance of urban-rural construction land, and compared with the current urban-rural construction land, analyzed the matching of the space layout, and then obtained the remaining development intensity of each county (city or district) of the Poyang Lake urban agglomeration. The results showed that the most suitable, more suitable, less suitable and unsuitable area about the evaluation results of urban-rural construction land development suitability were 3130.62, 2477.29, 867.03 and 29509.14 km2, respectively. The bearable critical threshold of urban-rural construction land (developable strength) was 16.6%, and the value of each county (city, district) was 7.7%-100%. The abundance of urban-rural construction land in each county (city, district) was mainly 0.15-1.30. The remaining development intensity was 12.3%, and the spatial matching degree was 0.76. The remaining develo-pment intensity of each county (city, district) was 4.9%-53.5%, and the spatial matching degree of each county (city, district) was 0.11- 1.00, with a wide range. Our results would help to clarify the relationship between the current development status and the rational development status, which could provide a basis for the refined management of urban-rural construction land and the regulatory policies' formulation of spatial pattern optimization.


Assuntos
Lagos , China , Cidades , Conservação dos Recursos Naturais
14.
Life Sci ; 233: 116700, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31356907

RESUMO

AIMS: Hydrogen (H2) has antioxidant effects. The pharmacologic function of H2 in platelets is not yet clear. Therefore, in this study we sought to investigate the inhibitory effects of H2 on in vitro platelet activation and in vivo prevention of thrombus formation. MAIN METHODS: After platelets were incubated with H2-rich saline (HRS), platelet adhesion in whole human blood was assessed in fibrinogen-coated perfusion chambers, while rat platelet aggregation induced by ADP, collagen and H2O2 was detected through light transmission aggregometry. The level of P-selectin, thromboxane B2, nitric oxide (NO), malondialdehyde, reactive oxygen species (ROS), cGMP, extracellular signal-regulated kinases 1 and 2 (p-ERK1/2), and fibrinogen binding to platelets were evaluated in vitro. Besides, the in vivo effects were examined in arterio-venous shunt thrombosis, FeCl3-induced artery thrombus formation, and tail bleeding time in mice and rats. KEY FINDINGS: HRS prolonged tail bleeding time in mice and rats, decreased thrombus weight and prolonged the time to occlusion in rat and mouse thrombosis models in vivo and inhibited platelet adhesion as well as aggregation in vitro. Additionally, HRS decreased P-selectin expression, release of thromboxane B2, ROS, and fibrinogen binding, but enhanced NO levels in H2O2-exposed platelets. HRS also decreased malondialdehyde levels in plasma of the rat arterial thrombosis or H2O2-exposed platelet model. Moreover, HRS increased cGMP level, decreased p-ERK1/2 (diminished with KT5823) in the platelets stimulated by H2O2. SIGNIFICANCE: These results suggest that H2 has antithrombotic effects, which may be due to its antioxidant property and subsequent inhibition of platelet activation via NO/cGMP/PKG/ERK pathway.


Assuntos
Antioxidantes/farmacologia , Hidrogênio/farmacologia , Ativação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Trombose/prevenção & controle , Animais , Biomarcadores/análise , Fibrinogênio/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Adesividade Plaquetária , Ratos , Ratos Sprague-Dawley , Trombose/etiologia , Trombose/patologia
15.
Thromb Res ; 123(2): 298-305, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18625517

RESUMO

Salvianolic acid B (SAB) is a component of Danshen, a herb widely used in Chinese medicine, and was previously shown to exert a number of biological activities including inhibition of platelet function, but the exact mechanisms involved are unclear. SAB dose-dependently inhibited platelet deposition from flowing, anticoagulated whole blood to immobilized collagen at both venous and arterial shear rate, whereas platelet deposition to immobilized fibrinogen was not affected. The inhibitory effect of SAB on platelet adhesion to collagen was independent of alphaIIbbeta3, since SAB still inhibited platelet deposition in the presence of a alphaIIbbeta3-blocking peptide. SAB inhibited static platelet adhesion to a synthetic peptide specific for the collagen receptor alpha2beta1, whereas platelet adhesion to a glycoprotein VI-specific peptide was not affected. SAB inhibited binding of an antibody against alpha2beta1 to platelets as studied by flow cytometry, and inhibited the interaction of soluble alpha2beta1 to immobilized collagen in a solid phase binding assay. These combined results indicate that SAB inhibits platelet adhesion to immobilized collagen by interfering with the collagen receptor alpha2beta1.


Assuntos
Benzofuranos/farmacologia , Hemorreologia/efeitos dos fármacos , Integrina alfa2beta1/metabolismo , Adesividade Plaquetária/efeitos dos fármacos , Receptores de Colágeno/metabolismo , Benzofuranos/isolamento & purificação , Adesão Celular/efeitos dos fármacos , Raízes de Plantas/química , Adesividade Plaquetária/fisiologia , Ligação Proteica/efeitos dos fármacos , Salvia/química , Solubilidade , Estresse Mecânico
16.
Thromb Res ; 121(6): 821-5, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17884149

RESUMO

A new improved flow system was developed to study the influence of blood flow pulsatility on platelet adhesion on adhesive proteins and bio-medical materials. The pulsatility was introduced by changing the shear rate every 15 s in blood that was aspirated through a perfusion chamber by a syringe pump. The advantage of this new system is that it avoids system related platelet activation. At steady low shear rate (300/s) after 5 min a collagen type III surface was covered for 24.2+/-3.8% with platelets. At steady high shear rate (1300/s) platelet coverage to collagen was 48.8+/-6.8%. When pulsatility was introduced by changing the shear rate was every 15 s form 300/s to 1300/s and vice-versa, platelet coverage after 5 min was increased to 60.4+/-4.0% (p<0.001). After 5 min perfusion samples were taken from the perfusate and the extent of platelet activation was measured. The significant difference in surface expression of P-selectin on platelets is only seen when comparing pulse flow with control (no flow). We concluded that a significant increase in platelet activation during blood pulsatile flow compared with steady flow, which results in an increased platelet adhesion to collagen.


Assuntos
Plaquetas/fisiologia , Hemorreologia/instrumentação , Modelos Cardiovasculares , Adesividade Plaquetária/fisiologia , Fluxo Pulsátil , Velocidade do Fluxo Sanguíneo , Plaquetas/química , Colágeno Tipo III/química , Colágeno Tipo III/metabolismo , Hemorreologia/métodos , Humanos , Selectina-P/análise , Valores de Referência , Sensibilidade e Especificidade , Propriedades de Superfície
17.
Chin J Physiol ; 51(3): 178-85, 2008 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-18935913

RESUMO

The possible effects of cervical lymphatic blockade (CLB) on a series of parameters in conscious freely moving rats were analysed. Blood pressure (BP) and heart rate (HR) for conscious male Sprague-Dawley rats at 1, 3, 7, 11, 15 and 21 days after a CLB or a sham operation were monitored continuously for 24 hours with a computerized recording system. Since BP and HR were subjected to spontaneous variations, blood pressure variability (BPV) and heart rate variability (HRV) were expressed as the standard deviation of beat-to-beat BP and HR values. The baroreflex sensitivities (BRS) were determined by measuring the heart period (HP = 60,000/HR) prolongation in response to the elevation in BP induced by an intravenous administration of phenylephrine at 1, 7, 15 and 21 days after the CLB or sham operation. Compared with those in sham-operated rats, the values of systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial blood pressure (MAP), HR and BRS in CLB rats were significantly lower, whereas the values of BPV and HRV were markedly raised in CLB rats at different time points. Furthermore, the impaired ultrastructure in the dorsomedial nucleus of the solitary tract (dmNTS) including degeneration, apoptosis and necrosis in neurons and gliacytes, were apparent from the 1st to 15th day but the changes were most significant at 7th day after CLB operation. Structural changes appeared to be closely related to functional changes of the dmNTS at each time point. Thus, in CLB conscious rats, a significant decline in blood pressure accompanied by dysfunction in its regulation might be due to the impaired structure in the dmNTS.


Assuntos
Pressão Sanguínea/fisiologia , Estado de Consciência/fisiologia , Frequência Cardíaca/fisiologia , Vasos Linfáticos/fisiologia , Vasos Linfáticos/cirurgia , Animais , Apoptose , Barorreflexo/fisiologia , Pressão Sanguínea/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Masculino , Necrose , Neurônios/patologia , Neurônios/ultraestrutura , Fenilefrina/farmacologia , Ratos , Ratos Sprague-Dawley , Núcleo Solitário/patologia , Núcleo Solitário/ultraestrutura , Vasoconstritores/farmacologia
18.
Thromb Haemost ; 118(12): 2086-2097, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30419596

RESUMO

It remains unclear whether plasma phospholipid transfer protein (PLTP) is involved in hyper-coagulation or hypo-coagulation. This study investigated the direct effect of PLTP on platelet aggregation and the underlying mechanism. Washed platelets from humans or mice and mouse platelet-rich plasma and human recombinant PLTP were isolated. PLTP is present in human platelets. We assessed adenosine diphosphate (ADP)-, collagen- and thrombin-induced platelet aggregation, phosphatidylserine externalization and photothrombosis-induced cerebral infarction in mice. PLTP over-expression increased platelet aggregation, while PLTP deficiency had the opposing reaction. Human recombinant PLTP increased both mouse and human platelet aggregation in a dose-dependent manner. Phosphatidylserine externalization provides a water/lipid surface for the interaction of coagulation factors, which accelerates thrombosis. Compared with wild-type controls, platelets from PLTP transgenic mice had significantly more phosphatidylserine on the exterior surface of the plasma membrane, whereas platelets from PLTP-deficient mice had significantly less phosphatidylserine on the surface, thus PLTP influences fibrinogen binding on the plasma membrane. Moreover, recombinant PLTP together with ADP significantly increased phosphatidylserine exposure on the plasma membrane of PLTP-deficient platelets, thereby increasing fibrinogen binding. PLTP over-expression significantly accelerated the incidence of photothrombosis-induced infarction in mice, whereas PLTP deficiency significantly reduced the frequency of infarction. We concluded that PLTP promotes phosphatidylserine externalization at the plasma membrane of platelets and accelerates ADP- or collagen-induced platelet aggregation. This effect plays an important role in the initiation of thrombin generation and platelet aggregation under sheer stress conditions. Thus, PLTP is involved in hyper-coagulation. Therefore, PLTP inhibition could be a novel approach for countering thrombosis.


Assuntos
Plaquetas/fisiologia , Membrana Celular/metabolismo , Infarto Cerebral/metabolismo , Proteínas de Transferência de Fosfolipídeos/metabolismo , Trombofilia/metabolismo , Difosfato de Adenosina/metabolismo , Animais , Plaquetas/ultraestrutura , Membrana Celular/ultraestrutura , Células Cultivadas , Infarto Cerebral/genética , Colágeno/metabolismo , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Fosfatidilserinas/metabolismo , Proteínas de Transferência de Fosfolipídeos/genética , Agregação Plaquetária/genética , Trombina/metabolismo , Trombofilia/genética
19.
Chin J Integr Med ; 13(2): 98-102, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17609906

RESUMO

OBJECTIVE: To observe the clinical effect of Astragalus Injection (, AI) and its immuno-regulatory action in treating chronic aplastic anemia (CAA). METHODS: Sixty patients with CAA were randomly assigned to two groups equally, both were treated with Stanozolol three times a day, 2 mg each time through oral intake, but AI was given additionally to the patients in the treated group once a day via intravenous dripping. All were treated for 15 days as one therapeutic course and the whole medication lasted for more than 4 months totally, with follow-up adopted. The clinical efficacy was estimated and the changes of T-lymphocyte subsets in peripheral blood as well as the serum levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin-2 (IL-2) were observed. RESULTS: The total effective rate in the treated group was 83.3% (25/30), which was higher than that in the control group 66.7% (20/30), showing significant difference between them (P<0.05). Levels of hemoglobin, WBC, reticular cell and platelet were elevated in both groups after treatment, but the improvement was significantly better in the treated group than that in the control group with respect to the former three indexes (P<0.05). The level of CD4(+) increased and that of CD8(+) decreased significantly after treatment in the treated group (P<0.05), which showed significant difference as compared with those in the control group (P<0.05). Levels of serum TNF-alpha and IL-2 lowered after treatment in both groups, but significance only showed in the treated group (P<0.05). The degree of proliferation in bone marrow got raised significantly and the percentage of non-hemopoietic cells reduced significantly in the treated group after treatment, also showing significant difference to those in the control group (P<0.05). CONCLUSION: AI could promote the recovery of hemopoietic function, which might be through improving T-lymphocyte subsets and reducing the release of negative regulatory factors such as TNF-alpha and IL-2 to alleviate the inhibition on hemopoietic function.


Assuntos
Anemia Aplástica/tratamento farmacológico , Astrágalo , Medicamentos de Ervas Chinesas/uso terapêutico , Anemia Aplástica/sangue , Anemia Aplástica/imunologia , Medula Óssea/efeitos dos fármacos , Doença Crônica , Seguimentos , Humanos , Injeções , Interleucina-2/sangue , Fator de Necrose Tumoral alfa/sangue
20.
Genes (Basel) ; 8(5)2017 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-28481269

RESUMO

RNA interference (RNAi), including microRNAs, is an important player in the mediation of differentiation and migration of stem cells via target genes. It is used as a potential strategy for gene therapy for central nervous system (CNS) diseases. Stem cells are considered vectors of RNAi due to their capacity to deliver RNAi to other cells. In this review, we discuss the recent advances in studies of RNAi pathways in controlling neuronal differentiation and migration of stem cells. We also highlight the utilization of a combination of RNAi and stem cells in treatment of CNS diseases.

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