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1.
Sci Rep ; 14(1): 15107, 2024 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956066

RESUMO

Ferroptosis is an iron-dependent cell death form characterized by reactive oxygen species (ROS) overgeneration and lipid peroxidation. Myricetin, a flavonoid that exists in numerous plants, exhibits potent antioxidant capacity. Given that iron accumulation and ROS-provoked dopaminergic neuron death are the two main pathological hallmarks of Parkinson's disease (PD), we aimed to investigate whether myricetin decreases neuronal death through suppressing ferroptosis. The PD models were established by intraperitoneally injecting 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) into rats and by treating SH-SY5Y cells with 1-methyl-4-phenylpyridinium (MPP+), respectively. Ferroptosis was identified by assessing the levels of Fe2+, ROS, malondialdehyde (MDA), and glutathione (GSH). The results demonstrated that myricetin treatment effectively mitigated MPTP-triggered motor impairment, dopamine neuronal death, and α-synuclein (α-Syn) accumulation in PD models. Myricetin also alleviated MPTP-induced ferroptosis, as evidenced by decreased levels of Fe2+, ROS, and MDA and increased levels of GSH in the substantia nigra (SN) and serum in PD models. All these changes were reversed by erastin, a ferroptosis activator. In vitro, myricetin treatment restored SH-SY5Y cell viability and alleviated MPP+-induced SH-SY5Y cell ferroptosis. Mechanistically, myricetin accelerated nuclear translocation of nuclear factor E2-related factor 2 (Nrf2) and subsequent glutathione peroxidase 4 (Gpx4) expression in MPP+-treated SH-SY5Y cells, two critical inhibitors of ferroptosis. Collectively, these data demonstrate that myricetin may be a potential agent for decreasing dopaminergic neuron death by inhibiting ferroptosis in PD.


Assuntos
Modelos Animais de Doenças , Neurônios Dopaminérgicos , Ferroptose , Flavonoides , Espécies Reativas de Oxigênio , Ferroptose/efeitos dos fármacos , Animais , Flavonoides/farmacologia , Ratos , Masculino , Espécies Reativas de Oxigênio/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Humanos , Doença de Parkinson/metabolismo , Doença de Parkinson/tratamento farmacológico , Linhagem Celular Tumoral , Ferro/metabolismo , alfa-Sinucleína/metabolismo , Ratos Sprague-Dawley , Glutationa/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/efeitos adversos , Fator 2 Relacionado a NF-E2/metabolismo
2.
Xenobiotica ; 54(1): 38-44, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38085693

RESUMO

Gefitinib is the first-generation drug of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) metabolised by the cytochrome P450 and transported by P-glycoprotein (ABCB1) and breast cancer resistance protein (ABCG2). In the present study, the pharmacokinetics of gefitinib in healthy Chinese volunteers was investigated and the effect of genetic polymorphisms on its variability was evaluted.Forty-five healthy volunteers were administered a single dose of gefitinib and the blood samples were used for quantifying the concentration of gefitinib and genotyping fifteen single-nucleotide polymorphisms of cytochrome P450 enzymes (CYP3A4, CYP3A5, CYP2D6, CYP2C9 and CYP2C19) and drug transporters (ABCB1 and ABCG2).CYP3A5*3 (rs776746) polymorphism showed a significant influence, with higher gefitinib AUC0-t in carrier of CC genotype than in CT/TT genotype (BH-adjusted p value <0.05). For CYP2C9*3 (rs1057910), significant differences in pharmacokinetics of gefitinib were detected between carriers of AA and AC genotypes, with higher AUC0-t, AUC0-∞ and Cmax in carrier of AC genotype than in AA gen-otype (BH-adjusted p value <0.05). No associations were found between SNPs in CYP3A4, CYP2D6, CYP2C19, ABCB1, ABCG2 and the pharmacokinetics of gefitinib.The SNPs in CYP3A5*3 (rs776746) and CYP2C9*3 (rs1057910) were found to be associated with altered gefitinib pharmacokinetics in healthy Chinese volunteers.


Assuntos
Citocromo P-450 CYP2D6 , Citocromo P-450 CYP3A , Humanos , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Gefitinibe , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Citocromo P-450 CYP2C19/genética , Citocromo P-450 CYP2C19/metabolismo , Citocromo P-450 CYP2D6/metabolismo , Voluntários Saudáveis , Citocromo P-450 CYP2C9/genética , Citocromo P-450 CYP2C9/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Polimorfismo de Nucleotídeo Único , Genótipo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , China
3.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(2): 216-221, 2021 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-33829694

RESUMO

OBJECTIVE: To investigate the effect of acrolein on the proliferation of pulmonary epithelial cells and its possible mechanism. METHODS: Two strains of pulmonary epithelial cells, A549 cells and MLE15 cells, were used as in vitro models of pulmonary epithelial cell, and were treated with 80 µmol/L acrolein or phosphate buffer saline (PBS) as the control. The proliferation of pulmonary epithelial cells were determined with CCK-8 kit after cell culturing resumed for 12 h, 24 h, 36 h and 48 h post acrolein treatment, and the expression of period circadian regulator gene 1 ( Per1) was examined using Western blot test 24 h after acrolein treatment. In addition, after acrolein treatment, the cells were restored with transforming growth factor-ß (TGF-ß) added in the medium, and the cell proliferation and the expression of Per1 protein were also examined. RESULTS: The proliferation of A549 cells and MLE15 cells decreased significantly after being treated with 80 µmol/L acrolein for 30 min, and the expression of Per1 protein was also downregulated significantly ( P<0.05). The addition of TGF-ß after acrolein treatment did not significantly change the reduction in cell proliferation caused by acrolein, but the expression of Per1 protein in pulmonary epithelial cells was significantly higher than that in cells restored without TGF-ß ( P<0.05). CONCLUSION: Acrolein treatment resulted in the decreased proliferation of pulmonary epithelial cells and the Per1 expression in pulmonary epithelial cells. Although TGF-ß addition did not reverse the reduction of cell proliferation after acrolein treatment, the Per1 expression levels were recovered to a certain extent compared to that in cells restored in medium without TGF-ß after acrolein treatment.


Assuntos
Acroleína , Células Epiteliais , Acroleína/farmacologia , Proliferação de Células , Expressão Gênica , Pulmão
4.
Sci Rep ; 9(1): 13869, 2019 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-31554874

RESUMO

We compared the therapeutic effects between botulinum toxin and surgery for acute acquired comitant esotropia (AACE) and analyze its clinical characteristics. The data of the 29 cases, who received treatment for AACE in the Ophthalmic Center of the First Affiliated Hospital of Zhengzhou University and Henan Provincial Ophthalmology Hospital between January 2016 and January 2017, were collected. The 29 cases with AACE were followed for 6 months or more, and received either botulinum toxin injection (group A with 13 cases) or squint correction (group B with 16 cases). The distant and near deviation angles were compared between the two groups before and after treatment. The success rate (total horizontal deviation of 10 prism diopters or less) and stereopsis were compared between the two groups at post-treatment 6 months. At the same time, the relations between distant and near deviation angles were analyzed among different myopia levels and different AACE types. Results indicated that he success rate was not significantly different at post-treatment 6 months (84.6% vs 81.3%, P = 1.00). The distant and near deviation angles were all significantly different one day and one month after treatment (all P < 0.05); but at post-treatment 6 months, they were not significantly different (all P > 0.05) between the two groups. There were no significant differences in the distant and near stereoacuity between the two groups at post-treatment 6 months (all P > 0.05). Among the 25 cases with myopia, the pre-treatment distant deviation angle was significantly higher than pre-treatment near deviation angle in the cases with myopia level >-2.5 D (P < 0.05), and the pre-treatment distant and near deviation angles were all significantly higher in the cases with type-IIAACE than in the cases with type-IIIAACE (all P < 0.05). This study suggests that Botulinum toxin is as effective as surgery in the treatment of AACE at post-treatment 6 months. For the cases with myopia level >-2.5 D, the pre-treatment distant deviation angle is significantly higher than pre-treatment near deviation angle; and both pre-treatment distant and near deviation angles are greater in the cases with type-IIAACE than in the cases with type-IIIAACE.


Assuntos
Toxinas Botulínicas Tipo A/uso terapêutico , Esotropia/tratamento farmacológico , Esotropia/cirurgia , Adolescente , Adulto , Toxinas Botulínicas Tipo A/administração & dosagem , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Resultado do Tratamento , Adulto Jovem
5.
J Exp Clin Cancer Res ; 35(1): 162, 2016 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-27733185

RESUMO

BACKGROUND: Gliomas are the most common type of primary brain tumour in the central nervous system of adults. The long non-coding RNA (lncRNA) HOXA transcript at the distal tip (HOTTIP) is transcribed from the 5' tip of the HOXA locus. HOTTIP has recently been shown to be dysregulated and play an important role in the progression of several cancers. However, little is known about whether and how HOTTIP regulates glioma development. METHODS: In this study, we assayed the expression of HOTTIP in glioma tissue samples and glioma cell lines using real-time polymerase chain reaction and defined the biological functions of HOTTIP using the CCK-8 assay, flow cytometry, terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL assay) and tumour formation assay in a nude mouse model. Finally, we discovered the underlying mechanism using the Apoptosis PCR 384HT Array, Western blot, RNA immunoprecipitation (RIP) and luciferase reporter assay. RESULTS: HOTTIP was aberrantly down-regulated in glioma tissues and glioma cell lines (U87-MG, U118-MG, U251 and A172), and over-expression of HOTTIP inhibited the growth of glioma cell lines in vitro and in vivo. Furthermore, HOTTIP could directly bind to the brain and reproductive expression (BRE) gene and down-regulate BRE gene expression. In addition, we further verified that over-expression of the BRE gene promoted the growth of glioma cell lines in vitro. Finally, over-expression of HOTTIP significantly suppressed the expression of the cyclin A and CDK2 proteins and increased the expression of the P53 protein. However, we found that the over-expression of BRE significantly increased the expression of the cyclin A and CDK2 proteins and suppressed the expression of the P53 protein. Taken together, these findings suggested that high levels of HOTTIP reduced glioma cell growth. Additionally, the mechanism of HOTTIP-mediated reduction of glioma cell growth may involve the suppression of cyclin A and CDK2 protein expression, which increases P53 protein expression via the down-regulation of BRE. CONCLUSIONS: Our studies demonstrated that over-expression of HOTTIP promotes cell apoptosis and inhibits cell growth in U118-MG and U87-MG human glioma cell lines by down-regulating BRE expression to regulate the expression of P53, CDK2 and Cyclin A proteins. The data described in this study indicate that HOTTIP is an interesting candidate for further functional studies in glioma and demonstrate the potential application of HOTTIP in glioma therapy.


Assuntos
Neoplasias Encefálicas/patologia , Glioma/patologia , Proteínas do Tecido Nervoso/genética , RNA Longo não Codificante/genética , Regulação para Cima , Regiões 3' não Traduzidas , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Ciclina A/metabolismo , Quinase 2 Dependente de Ciclina/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Glioma/metabolismo , Humanos , Masculino , Camundongos , Transplante de Neoplasias , Proteína Supressora de Tumor p53/metabolismo
6.
J Neuroimmune Pharmacol ; 10(3): 506-16, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25773257

RESUMO

Multiple sclerosis (MS) is the prototypical inflammatory demyelinating disease of the central nervous system (CNS), and MS results in physical and cognitive impairments, such as fatigue, pain, depression and bladder dysfunction. Though many therapies for MS have been developed, the safety profile and effectiveness of these therapies still need to be defined. Thus, new therapies for MS must be explored. Celastrol, a quinonemethide triterpene, is a pharmacologically active compound present in Thunder God Vine root extracts used to treat inflammatory and autoimmune diseases. Molecular studies have identified several molecular targets, which are mostly centered on the inhibition of IKK-NF-κB signaling. The animal model of experimental autoimmune encephalomyelitis (EAE) has been widely used in MS studies; thus, we tried to explore the role of celastrol in EAE development in this study. We demonstrated that the intraperitoneal injection of celastrol significantly attenuated EAE disease. Th17 cell responses in the peripheral lymph nodes in EAE mice were also inhibited by celastrol. We determined that celastroldownregulated cytokine production in bone-marrow derived dendritic cells (BMDCs). Accordingly, T cells that were co-cultured with either BMDCs pre-treated with celastrolor splenic DCs and then collected on day 7 after EAE immunizationshowed that Th17 cell polarization is suppressed in the above two situations. Moreover, celastrol was required for tissue-infiltrating DCs to sustain Th17 responses in the central nervous system (CNS). Taken together, the results of our study demonstrate that celastrol ameliorates EAE development by suppressing pathogenic Th17 responses; this finding offers a better understanding of the role of celastrol in EAE development as well as new proposals for clinical interventions.


Assuntos
Sistema Nervoso Central/efeitos dos fármacos , Encefalomielite Autoimune Experimental/tratamento farmacológico , Esclerose Múltipla/tratamento farmacológico , Sistema Nervoso Periférico/efeitos dos fármacos , Células Th17/efeitos dos fármacos , Triterpenos/farmacologia , Animais , Células da Medula Óssea/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B , Triterpenos Pentacíclicos , Triterpenos/administração & dosagem
7.
Chin Med J (Engl) ; 128(5): 670-3, 2015 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-25698202

RESUMO

BACKGROUND: Non-small cell lung cancer (NSCLC) is a prolific and high-mortality disease with few effective treatments. Although the detection and surgical techniques for NSCLC continue to advance, the survival rate for the patients with NSCLC remains poor. Enhanced predictive biomarkers such as microRNAs (miRNAs) are needed at the time of diagnosis to better tailor therapies for patients. This study focused on the expression of miR-1280 in NSCLC tissues and distal normal tissues in order to explore the association between miR-1280 expression and NSCLC. METHODS: A total of 72 newly diagnosed primary NSCLC patients were enrolled in this study. Quantitative real-time polymerase chain reaction (PCR) was performed to identify the expression level of miR-1280 in the NSCLC tissues and distal normal tissues of these patients. RESULTS: The miR-1280 expression was significantly higher in the NSCLC tissues (0.084 ± 0.099) than distal normal tissues (0.014 ± 0.015, P = 0.009). In 54 patients (75%), the miR-1280 expression in the NSCLC tissues was upregulated (2-ΔΔct > 2), and no case showed a downregulation of miR-1280 expression. CONCLUSIONS: The expression level of miR-1280 could be regarded as a biomarker for NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , MicroRNAs/genética , Idoso , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Regulação para Cima
8.
PLoS One ; 9(8): e105131, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25116125

RESUMO

All-trans retinoic acid (ATRA) is a revolutionary agent for acute promyelocytic leukemia (APL) treatment via differentiation induction. However, ATRA treatment also increases cytokine, chemokine, and adhesive molecule (mainly ICAM-1) expression, which can cause clinical complications, including a severe situation known as differentiation syndrome (DS) which can cause death. Therefore, it is of clinical significance to find a strategy to specifically blunt inflammatory effects while preserving differentiation. Here we report that the natural compound, celastrol, could effectively block lung infiltrations in DS animal models created by loading ATRA-induced APL cell line NB4. In ATRA-treated NB4 cells, celastrol could potently inhibit ICAM-1 elevation and partially reduce TNF-α and IL-1ß secretion, though treatment showed no effects on IL-8 and MCP-1 levels. Celastrol's effect on ICAM-1 in ATRA-treated NB4 was related to reducing MEK1/ERK1 activation. Strikingly and encouragingly, celastrol showed no obvious effects on ATRA-induced NB4 differentiation, as determined by morphology, enzymes, and surface markers. Our results show that celastrol is a promising and unique agent for managing the side effects of ATRA application on APL, and suggest that hyper-inflammatory ability is accompanied by, but not necessary for, APL differentiation. Thus we offered an encouraging novel strategy to further improve differentiation therapy.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Leucemia Promielocítica Aguda/tratamento farmacológico , Pulmão/efeitos dos fármacos , Tretinoína/efeitos adversos , Triterpenos/farmacologia , Animais , Linhagem Celular Tumoral , Humanos , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Leucemia Promielocítica Aguda/metabolismo , Leucemia Promielocítica Aguda/patologia , Pulmão/metabolismo , Pulmão/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Triterpenos Pentacíclicos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Síndrome , Tretinoína/uso terapêutico , Fator de Necrose Tumoral alfa/metabolismo
9.
Cytometry A ; 85(4): 359-67, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24265268

RESUMO

Flow cytometry, in conjunction with immunoprecipitation (IP-FCM), is suggested to have some advantages to conventional IP-western blot technology in analyzing protein complexes. In this paper, to further examine its practicability, we test the use of IP-FCM in detecting the HSP90 complex, which has gained importance in drug research and development and involves more than a dozen components. We found that IP-FCM could effectively detect HSP70, p23, Cdc37, and Cdk6 components in the HSP90 complex naturally formed in U937 cells when this complex was captured by anti-HSP90 antibody-coated polystyrene microspheres. IP-FCM could also detect alteration in components caused by treating cells with HSP90 inhibitors. In a cell-free environment, IP-FCM could detect the direct effects of ATP and/or HSP90 inhibitors (17-N-allylamino-17-demethoxygeldanamycin or celastrol) in causing component dissociation and the time- and dose-effects of inhibitor-caused dissociation. IP-FCM is a practical and powerful platform for analyzing HSP90 complex components, and is thus a useful tool in studying HSP90 complex function and screening inhibitors.


Assuntos
Citometria de Fluxo/métodos , Proteínas de Choque Térmico HSP90/análise , Imunoprecipitação/métodos , Western Blotting , Linhagem Celular Tumoral , Humanos , Microesferas
10.
Nat Genet ; 42(11): 1005-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20953187

RESUMO

We extended our previous genome-wide association study for psoriasis with a multistage replication study including 8,312 individuals with psoriasis (cases) and 12,919 controls from China as well as 3,293 cases and 4,188 controls from Germany and the United States and 254 nuclear families from the United States. We identified six new susceptibility loci associated with psoriasis in the Chinese study containing the candidate genes ERAP1, PTTG1, CSMD1, GJB2, SERPINB8 and ZNF816A (combined P < 5 × 10⁻8) and replicated one locus, 5q33.1 (TNIP1-ANXA6), previously reported (combined P = 3.8 × 10⁻²¹) in the European studies. Two of these loci showed evidence for association in the German study at ZNF816A and GJB2 with P = 3.6 × 10⁻³ and P = 7.9 × 10⁻³, respectively. ERAP1 and ZNF816A were associated with type 1 (early onset) psoriasis in the Chinese Han population (test for heterogeneity P = 6.5 × 10⁻³ and P = 1.5 × 10⁻³, respectively). Comparisons with the results of previous GWAS of psoriasis highlight the heterogeneity of disease susceptibility between the Chinese and European populations. Our study identifies new genetic susceptibility factors and suggests new biological pathways in psoriasis.


Assuntos
Povo Asiático/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único , Psoríase/genética , Aminopeptidases/genética , Conexina 26 , Conexinas/genética , Replicação do DNA , Alemanha/epidemiologia , Humanos , Proteínas de Membrana/genética , Antígenos de Histocompatibilidade Menor , Proteínas de Neoplasias/genética , Securina , Serpinas/genética , Proteínas Supressoras de Tumor , Estados Unidos/epidemiologia
12.
Zhong Xi Yi Jie He Xue Bao ; 5(3): 282-6, 2007 May.
Artigo em Chinês | MEDLINE | ID: mdl-17498488

RESUMO

OBJECTIVE: Increasing of adhesion between leukemia cells and endothelial cells during all-trans retinoic acid (ATRA) treatment plays an important role in retinoic acid syndrome. This work observed the effects of tripterine on this ATRA-caused increasing in adhesion. METHODS: The effects of tripterine on ATRA-induced expressions of adhesive molecules in acute promyelocytic leukemia cell line NB4 and human umbilical vascular endothelial cells (HUVEC) were detected by flow cytometry. The effects of tripterine on adhesion between ATRA-treated NB4 and HUVEC were determined by adhesive assays. RESULTS: ATRA caused remarkable elevation of intercellular adhesion molecule-1 (ICAM-1) in NB4 cells, which could be significantly reduced by tripterine (P<0.01). The expressions of E-selectin, vascular cell adhesion molecule-1 (VCAM-1) and ICAM-1 in HUVEC were elevated by conditioned medium from ATRA-induced NB4 (ATRA-NB4-CM) (P<0.01), and inhibited by tripterine with inhibition rates being 25.3%, 42.4% and 61.0% respectively. ATRA increased the adhesion between NB4 and HUVEC, which was reversed completely by tripterine. CONCLUSION: Tripterine can inhibit ATRA-caused adhesion between leukemia cells and endothelial cells, and it might be a potential agent for treating retinoic acid syndrome.


Assuntos
Células Endoteliais/efeitos dos fármacos , Tretinoína/farmacologia , Triterpenos/farmacologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Selectina E/biossíntese , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/biossíntese , Leucemia Promielocítica Aguda/metabolismo , Leucemia Promielocítica Aguda/patologia , Triterpenos Pentacíclicos , Tripterygium/química , Molécula 1 de Adesão de Célula Vascular/biossíntese
13.
J Leukoc Biol ; 80(2): 309-19, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16769766

RESUMO

Cell adhesion molecules (CAM) expressed by vascular endothelium in response to cytokine stimulation play a key role in leukocyte adhesion to endothelium during the inflammatory response. Tripterine, a chemical compound of the Chinese plant Tripterygium wilfordii Hook f, displays anti-inflammatory properties in several animal models. However, mechanisms of its action are poorly understood. In the present study, we show that in inflammatory conditions, mimicked by tumor necrosis factor alpha (TNF-alpha) stimulation, pretreatment for 6 h with tripterine at nontoxic concentrations of 20-200 nM inhibits the expression of E-selectin, vascular cell adhesion molecule (CAM)-1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1) in human umbilical vein endothelial cells (HUVEC) in a dose-dependent manner. Tripterine (200 nM) almost completely inhibits expression of VCAM-1 [50% inhibitory concentration (IC50) = 52 nM] and ICAM-1 (IC50 = 51 nM) and 73% of E-selectin (IC50 = 94 nM). This inhibition effect is prominent, compared with that of dexamethasone, ibuprofen, methotrexate, or probucol, which revealed a much weaker inhibition at doses as high as 1 mM. Effects on endothelial CAM of other proinflammatory cytokines, such as interleukin-1beta and interferon-gamma, were also inhibited significantly by tripterine. Moreover, significant inhibition was equally observable in postincubation experiments. In addition, tripterine inhibited adhesion of human monocytes and T lymphocytes to TNF-alpha-stimulated HUVEC. Finally, tripterine inhibited TNF-alpha-driven CAM mRNA transcription and nuclear factor-kappaB nuclear (NF-kappaB) translocation. Hence, we describe a new mechanism of tripterine's anti-inflammatory action obtained at nanomolar concentrations, owing to the negative regulation of cytokine-induced adhesion molecule expression and adhesiveness in human endothelium.


Assuntos
Anti-Inflamatórios/farmacologia , Moléculas de Adesão Celular/metabolismo , Células Endoteliais/fisiologia , Molécula 1 de Adesão Intercelular/metabolismo , Triterpenos/farmacologia , Molécula 1 de Adesão de Célula Vascular/metabolismo , Linhagem Celular , Proliferação de Células , Sobrevivência Celular , Relação Dose-Resposta a Droga , Humanos , Interferon gama/farmacologia , Interleucina-1/farmacologia , Modelos Moleculares , NF-kappa B/metabolismo , Triterpenos Pentacíclicos , Fator de Necrose Tumoral alfa/farmacologia
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