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1.
Trials ; 24(1): 429, 2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37355630

RESUMO

BACKGROUND: Recent studies have demonstrated a correlation between intestinal flora and the severity of myocardial infarction as well as post-myocardial infarction repair. However, few studies have investigated whether probiotics reduce mortality and improve cardiovascular outcomes in patients with acute myocardial infarction. In this study, we will conduct a randomized controlled trial (RCT) to evaluate the effect of probiotics on in-hospital mortality and the incidence of major adverse cardiovascular events (MACE) in patients with acute myocardial infarction (AMI). METHODS: This is an open-label, randomized, controlled, superiority clinical trial involving 2594 adult patients who were diagnosed with acute myocardial infarction. Patients will be randomized to (1) receive bifidobacteria triple viable capsule (Bifidobacterium longum, Lactobacillus acidophilus, and Enterococcus faecalis) 840 mg, twice a day, plus standard treatment strategy during the hospital stay, for a maximum of 30 days, or (2) receive the standard treatment strategy and will not take the bifidobacterium triple live capsule. The primary outcome was in-hospital all-cause mortality. DISCUSSION: The purpose of this clinical trial is to determine whether probiotics can reduce in-hospital mortality and improve prognosis in patients with AMI, and the results will provide evidence for probiotics as a complementary treatment for AMI. TRIAL REGISTRATION: Chinese Clinical Trials Registry ChiCTR2000038797. Registered on 2 October 2020.


Assuntos
Infarto do Miocárdio , Probióticos , Adulto , Humanos , Mortalidade Hospitalar , Tempo de Internação , Infarto do Miocárdio/terapia , Infarto do Miocárdio/tratamento farmacológico , Probióticos/uso terapêutico , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
2.
G3 (Bethesda) ; 13(6)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37154439

RESUMO

Maintaining a definite and stable pool of dividing stem cells plays an important role in organ development. This process requires an appropriate progression of mitosis for proper spindle orientation and polarity to ensure the ability of stem cells to proliferate and differentiate correctly. Polo-like kinases (Plks)/Polo are the highly conserved serine/threonine kinases involved in the initiation of mitosis as well as in the progression of the cell cycle. Although numerous studies have investigated the mitotic defects upon loss of Plks/Polo in cells, little is known about the in vivo consequences of stem cells with abnormal Polo activity in the context of tissue and organism development. The current study aimed to investigate this question using the Drosophila intestine, an organ dynamically maintained by the intestinal stem cells (ISCs). The results indicated that the polo depletion caused a reduction in the gut size due to a gradual decrease in the number of functional ISCs. Interestingly, the polo-deficient ISCs showed an extended G2/M phase and aneuploidy and were subsequently eliminated by premature differentiation into enterocytes (ECs). In contrast, the constitutively active Polo (poloT182D) suppressed ISC proliferation, induced abnormal accumulation of ß-tubulin in cells, and drove ISC loss via apoptosis. Therefore, Polo activity should be properly maintained for optimal stem cell function. Further analysis suggested that polo was a direct target gene of Sox21a, a Sox transcription factor that critically regulates stem cell activity. Together, this study provided a novel perspective on the correlation between the progression of mitosis and the ISC function in Drosophila.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Ciclo Celular/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Intestinos , Mitose/genética , Células-Tronco/metabolismo
3.
Front Cardiovasc Med ; 9: 963103, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36312256

RESUMO

Aim: The aim of this study is to evaluate the association between serum sodium concentrations at hospital admission and all-cause mortality within 365 days post-discharge in patients with atrial fibrillation (AF) without heart failure (HF). Methods: The prospective cohort study enrolled 1,446 patients with AF without HF between November 2018 and October 2020. A follow-up was performed 30, 90, 180, and 365 days after enrollment through outpatient visits or telephone interviews. All-cause mortality was estimated in three groups according to serum sodium concentrations: hyponatremia (< 135 mmol/L), normonatremia (135-145 mmol/L), and hypernatremia (> 145 mmol/L). We estimated the risk of all-cause mortalities using univariable and multivariable Cox proportional hazards models with normonatremia as the reference. Results: The all-cause mortalities of hyponatremia, normonatremia, and hypernatremia were 20.6, 9.4, and 33.3% within 365 days post-discharge, respectively. In the univariable analysis, hyponatremia (HR: 2.19, CI 1.5-3.2) and hypernatremia (HR: 4.03, CI 2.32-7.02) increased the risk of all-cause mortality. The HRs for hyponatremia and hypernatremia were 1.55 (CI 1.05-2.28) and 2.55 (CI 1.45-4.46) after adjustment for age, diabetes mellitus, loop diuretics, antisterone, antiplatelet drugs, and anticoagulants in the patients with AF without HF. The association between serum sodium concentrations and the HRs of all-cause mortality was U-shaped. Conclusion: Dysnatremia at hospital admission was an independent factor for all-cause mortality in patients with AF without HF within 365 days post-discharge.

4.
Dev Comp Immunol ; 131: 104361, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35143809

RESUMO

Prophenoloxidase (PPO), an important immunity protein in insects, is mainly produced by hemocytes and released into the hemolymph upon cell lysis. In addition, PPO can also be produced by epidermal cells in the foregut to detoxify the toxic plant secondary metabolites and in the hindgut to kill pathogens through PPO-induced melanization. Previously, we noticed a pair of tubes extended from the larval hindgut became melanized upon staining in dopamine dissolved in 30% ethanol. However, the structure and function of these tubes are largely unknown. In this study, we performed staining of the tubes and the neighboring Malpighian tubule for further confirmation. Eventually, we detected PPO inside epidermal cells of the tubes, and called them as PPO-positive tubes. We observed that the PPO-positive tubes are physically derived from the hindgut but strongly adhere to the Malpighian tubule. Inside the PPO-positive tubes, there is an acellular peritrophic membrane to protect the epidermal cells. Furthermore, the PPO-positive tubes act like a doorkeeper to firstly detoxify the metabolite wastes collected by the Malpighian tubule from the hemolymph.


Assuntos
Lepidópteros , Túbulos de Malpighi , Animais , Catecol Oxidase/metabolismo , Precursores Enzimáticos/metabolismo , Túbulos de Malpighi/metabolismo
5.
Hypertens Res ; 45(4): 715-721, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35169279

RESUMO

Uterine fibroids (UFs) are the most common benign gynecological tumor and greatly affect reproductive health in women of reproductive age. Some studies have indicated an association between UFs and several cardiovascular disease (CVD) risk factors. To determine whether UFs are associated with increased blood pressure, we performed a cross-sectional study and meta-analysis. In the cross-sectional study, 8401 participants who underwent a physical examination at the First Affiliated Hospital of Shantou University Medical College from June 2011 to June 2013 were divided into a uterine fibroid group (1617 cases) and a control group (6784 cases) to assess the relationship between UFs and blood pressure. Then, we conducted a systematic review to confirm the results. The cross-sectional study showed that UFs were associated with an increased rate of elevated blood pressure [OR = 1.35, 95% confidence interval (CI): 1.016-1.792]. The meta-analysis revealed a significant association between UFs and the prevalence of hypertension [pooled OR = 1.44, 95% CI: 1.17-1.75, P = 0.0004; I2 = 68%]. Thus, UFs may be associated with the prevalence of hypertension. Women with uterine fibroids should be closely monitored for hypertension.


Assuntos
Hipertensão , Leiomioma , Neoplasias Uterinas , Pressão Sanguínea , Estudos Transversais , Feminino , Humanos , Hipertensão/complicações , Hipertensão/epidemiologia , Leiomioma/complicações , Leiomioma/epidemiologia , Neoplasias Uterinas/complicações , Neoplasias Uterinas/epidemiologia
6.
Front Immunol ; 12: 741797, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34603328

RESUMO

Entomopathogenic fungi Beauveria bassiana can infect many species of insects and is used as a biological pesticide world-wide. Before reaching the hemocoel, B. bassiana has to penetrate the integument which is composed of a thick chitin layer and epidermal cells. Some chitinase, protease and lipase secreted by B. bassiana are probably involved in the fungal penetration of the integument. While microscopic proof is needed, it is difficult to locate the precise infection sites following the traditional method of immersion infection. Consequently, we developed a new method to inoculate conidia solution into a single fixed-site on the back of one segment. This fixed-site infection method is pathogenic but it is also dose dependent. Using the fixed-site infection protocol, it is also very convenient to track hyphae inside the cuticle layer by light and transmission electron microscopy. The fact that few hyphae were detected inside the chitin layer after fixed-site infection with mutant ΔBPS8, a protease secreted during fungi germination, indicates that this method is suitable for screening genes involved in penetrating the integument in large scale. We also found that melanization occurs before new hyphae penetrate the chitin layer. Most importantly, we discovered that fungal infection can induce epidermal cell proliferation through DNA duplication and cell division, which is essential for the host to defend against fungal infection. Taken together the fixed-site infection method may be helpful to determine the mechanism of fungal and host interaction in the integument so as to effectively exert fungal biological virulence.


Assuntos
Beauveria/fisiologia , Bombyx/imunologia , Quitina/metabolismo , Epiderme/metabolismo , Micoses/imunologia , Animais , Proliferação de Células , Quitinases/metabolismo , Epiderme/patologia , Interações entre Hospedeiro e Microrganismos , Hifas , Proteínas de Insetos/metabolismo , Lipase/metabolismo , Microscopia Eletrônica de Transmissão , Mutação/genética , Peptídeo Hidrolases/metabolismo , Controle de Pragas , Esporos Fúngicos , Virulência
7.
Onco Targets Ther ; 14: 3813-3820, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34188489

RESUMO

INTRODUCTION: Esophageal cancer (EC) is an aggressive cancer type that is increasing at a high rate in the US and worldwide. Extensive sequencing of EC specimens has shown that there are no consistent driver mutations that can impact treatment strategies. The goal of this study was to identify activated tyrosine kinase receptors (TKRs) in EC samples as potential targets in the treatment of EC. METHODS: Activated tyrosine kinase receptors were detected using a dot-blot array for human TK receptors. Human esophageal cancer cell lines were transplanted into immunocompromised mice, and tumor xenografts were subjected to tyrosine kinase inhibitors based on the dot-blot array data. RESULTS: Using the OE33 esophageal cancer cell line, we identified activated EGF receptor (EGFR), as well as ErbB2 and ErbB3. Treatment of this cell line with erlotinib, a specific inhibitor of EGFR, did not impact the growth of this tumor cell line. Treating the OE33 cell line with afatinib, a pan-EGFR family inhibitor resulted in the growth inhibition of OE33, indicating that the ErbB2 and ErbB3 receptors were contributing to tumor cell proliferation. Afatinib treatment of mice growing OE33 tumors inhibited growth of the OE33 tumor cells. DISCUSSION: Activated tyrosine kinase receptors were readily detected in both cancer cell lines and human esophageal cancer samples. By identifying the activated receptors and then using the appropriate tyrosine kinase inhibitors, we can block tumor growth in vitro and in animal xenografts. We propose that identifying and targeting activated TKRs can be used as a personalized EC tumor treatment strategy.

8.
Mitochondrial DNA B Resour ; 6(1): 3-5, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33490583

RESUMO

Here, combining PacBio and Illumina sequencing data, we reported the complete chloroplast genome of the first Wuyi tea (Bohea), Camellia sinensis cv. Dahongpao (DHP) with very high economic value. The chloroplast genome was 157,077 bp in length, with a large single copy (LSC) region of 86,633 bp, a small single-copy (SSC) region of 18,282 bp, separated by two inverted repeat (IR) regions of 26,081 bp each. It contained a total of 137 genes, with an overall GC content of 37.29%. The phylogenetic analysis showed that DHP was sister to C. sinensis cv. Longjing.

9.
Environ Pollut ; 266(Pt 2): 115119, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32623072

RESUMO

The extensive use of neonicotinoids (NEOs) has caused the release of wide-ranging of residues to the environment and food, and their potential health risks are now receiving more attention. In this study, three surveys were conducted to obtain the overall profiles of NEO residue levels (seven NEOs and one metabolite) in Chinese tea over a period of seven years. A total of 726 tea samples were tested, and nearly 87% of the samples were found to have detectable NEO residues. The overall average detection frequency of acetamiprid was the highest, reaching 73%. Imidacloprid residues in 4.6% of the samples exceeded the Chinese maximum residue limits, whereas clothianidin and nitenpyram had been detected in Chinese tea samples since 2014. The applications of thiacloprid and thiamethoxam gradually increased, and some tea samples with high residue levels appeared in China. These findings signal the replacement of new and old varieties of NEOs in China. Both long- and short-term cumulative exposures to NEOs were calculated based on optimistic and pessimistic models recommended in the EFSA guidelines. In the three survey periods, the average total imidacloprid-equivalent concentrations were 484.63, 1713.36, and 1148.34 µg/kg, respectively. Combined with the refined point estimates and probabilistic models used in this study, the hazard quotients of NEO residues in tea for Chinese tea consumers were found to be low and within the bounds of safety.


Assuntos
Inseticidas/análise , China , Neonicotinoides , Nitrocompostos/análise , Medição de Risco , Chá
10.
J Plant Physiol ; 168(7): 644-52, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21315475

RESUMO

Self-rooted, 10-month-old, uniform tea [Camellia sinensis (L.) O. Kuntze cv. Huangguanyin] plants were supplied for 17 weeks with 0, 40, 80, 160, 400, or 1000µM phosphorus (P) to investigate the effects of P supply on root citrate and malate release, the concentrations of malate and citrate and the activities of acid-metabolizing enzymes in leaves and roots. Root malate release and accumulation was induced by both 0 and 40µM P, while root citrate release and accumulation was induced only by 0µM P. Phosphorus-deficiency-induced malate and citrate release coincided with higher concentrations of root malate and citrate. The higher concentrations of malate and citrate were accompanied by increased activities of phosphoenolpyruvate carboxylase (PEPC), phosphoenolpyruvate phosphatase (PEPP), citrate synthase (CS) and NAD-malic enzyme (NAD-ME) and decreased activities of pyruvate kinase (PK), NADP-ME and NADP-isocitrate dehydrogenase (NADP-IDH) in roots. In contrast to roots, malate accumulated in the leaves only in response to 0µM P, and no change was observed in citrate levels. The P-deficiency-induced leaf malate accumulation coincided with increased activities of NADP-ME, NAD-ME and PK. Overall, the P-deficiency-induced changes in organic acid (OA) metabolism differed between roots and leaves. The high tolerance of tea plants to P-deficiency might be involved in two major processes: (a) increasing the availability of P by inducing root release of OA anions; and (b) improving the ability to use P efficiently by inducing bypass enzymes involved in tissue P economy.


Assuntos
Camellia sinensis/efeitos dos fármacos , Camellia sinensis/metabolismo , Ácido Cítrico/metabolismo , Malatos/metabolismo , Fósforo/farmacologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Camellia sinensis/enzimologia , Citrato (si)-Sintase/metabolismo , Isocitrato Desidrogenase/metabolismo , Fosfoenolpiruvato Carboxilase/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/enzimologia , Folhas de Planta/metabolismo , Raízes de Plantas/enzimologia
11.
BMC Plant Biol ; 9: 43, 2009 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-19379526

RESUMO

BACKGROUND: Although the effects of P deficiency on tea (Camellia sinensis (L.) O. Kuntze) growth, P uptake and utilization as well as leaf gas exchange and Chl a fluorescence have been investigated, very little is known about the effects of P deficiency on photosynthetic electron transport, photosynthetic enzymes and carbohydrates of tea leaves. In this study, own-rooted 10-month-old tea trees were supplied three times weekly for 17 weeks with 500 mL of nutrient solution at a P concentration of 0, 40, 80, 160, 400 or 1000 microM. This objective of this study was to determine how P deficiency affects CO2 assimilation, Rubisco, carbohydrates and photosynthetic electron transport in tea leaves to understand the mechanism by which P deficiency leads to a decrease in CO2 assimilation. RESULTS: Both root and shoot dry weight increased as P supply increased from 0 to 160 microM, then remained unchanged. P-deficient leaves from 0 to 80 muM P-treated trees showed decreased CO2 assimilation and stomatal conductance, but increased intercellular CO2 concentration. Both initial and total Rubisco activity, contents of Chl and total soluble protein in P-deficient leaves decreased to a lesser extent than CO2 assimilation. Contents of sucrose and starch were decreased in P-deficient leaves, whereas contents of glucose and fructose did not change significantly except for a significant increase in the lowest P leaves. OJIP transients from P-deficient leaves displayed a rise at the O-step and a depression at the P-step, accompanied by two new steps at about 150 mus (L-step) and at about 300 mus (K-step). RC/CSo, TRo/ABS (or Fv/Fm), ETo/ABS, REo/ABS, maximum amplitude of IP phase, PIabs and PItot, abs were decreased in P-deficient leaves, while VJ, VI and dissipated energy were increased. CONCLUSION: P deficiency decreased photosynthetic electron transport capacity by impairing the whole electron transport chain from the PSII donor side up to the PSI, thus decreasing ATP content which limits RuBP regeneration, and hence, the rate of CO2 assimilation. Energy dissipation is enhanced to protect P-deficient leaves from photo-oxidative damage in high light.


Assuntos
Camellia sinensis/metabolismo , Metabolismo dos Carboidratos , Dióxido de Carbono/metabolismo , Fósforo/metabolismo , Fotossíntese/fisiologia , Ribulose-Bifosfato Carboxilase/metabolismo , Camellia sinensis/crescimento & desenvolvimento , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo
12.
Mol Cancer Ther ; 6(5): 1509-16, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17483439

RESUMO

In this work, we evaluated two lead compounds, referred to as SG410 and SG430, obtained from a screen of sulfur benzoylphenylurea analogues, against in vitro and in vivo models of pancreas cancer. Both drugs showed a similar mechanism of action profile, with SG410 being more potent as an inhibitor of tubulin assembly. We determined the best in vivo administration schedule and tested SG410 and SG430 in nine cases of a novel platform of direct pancreas cancer xenografts. Both compounds had antiproliferative activity in vitro in the low nanomolar range, but only SG410 showed significant activity in vivo. Administration of SG410 resulted in significant tumor growth delay in five of nine groups tested. In a direct comparison in three of the cases, SG410 was at least as efficacious as docetaxel. We also sought markers that would be predictive of the efficacy of these agents, and we found such a marker in microtubule-associated protein tau (MAPT). This protein enhances the assembly and stability of microtubules. In both the cell lines and the direct human xenografts, MAPT mRNA and protein levels correlated well. There was also a statistically significant inverse correlation between MAPT expression and sensitivity to the tested agents. In summary, the novel sulfur benzoylphenylurea SG410 showed activity inversely related to MAPT expression in a preclinical model of pancreatic cancer comparable with that observed with docetaxel, another microtubule-targeting agent.


Assuntos
Antineoplásicos/farmacologia , Regulação Neoplásica da Expressão Gênica , Microtúbulos/química , Neoplasias Pancreáticas/tratamento farmacológico , Compostos de Fenilureia/síntese química , Enxofre/química , Proteínas tau/fisiologia , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Docetaxel , Feminino , Camundongos , Camundongos Nus , Transplante de Neoplasias , Compostos de Fenilureia/química , Taxoides/farmacologia , Tubulina (Proteína)/química , Tubulina (Proteína)/metabolismo , Proteínas tau/metabolismo
13.
Immunology ; 117(1): 29-37, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16423038

RESUMO

Although interleukin 13 (IL-13) is an important mediator of asthma and allergic diseases, the molecular mechanisms regulating IL-13 gene expression are not well understood. This study was designed to define the molecular mechanisms governing IL-13 gene expression in T cells. IL-13 expression was examined in human peripheral blood T cells and in the EL-4 T-cell line by enzyme-linked immunosorbent assay and reverse-transcription polymerase chain reaction. An IL-13 promoter deletion analysis was performed using luciferase-based reporter plasmids transiently transfected into EL-4 cells by electroporation. DNA binding factors were investigated using electrophoretic mobility shift assays. In contrast to IL-4 expression, which required concomitant activation of calcium- and protein kinase C- (PKC-) dependent signalling pathways, PKC activation alone was sufficient for IL-13 protein secretion in mitogen-primed (but not resting) peripheral blood T cells, and for IL-13 mRNA expression and promoter activity in EL-4 T cells. Promoter deletion analysis localized a phorbol 12-myristate 13-acetate (PMA)-sensitive element to a proximal promoter region between -109 and -79 base pairs upstream from the IL-13 transcription start site. This promoter region supported the binding of both constitutive and PMA-inducible nuclear factors in gel shift assays.


Assuntos
Interleucina-13/metabolismo , Linfócitos T/imunologia , Acetato de Tetradecanoilforbol/imunologia , Animais , Sequência de Bases , Linhagem Celular , Células Cultivadas , Regulação da Expressão Gênica/imunologia , Humanos , Interleucina-13/genética , Interleucina-13/imunologia , Camundongos , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Proteína Quinase C/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Transdução de Sinais/imunologia , Especificidade da Espécie , Transcrição Gênica/imunologia
14.
Am J Physiol Lung Cell Mol Physiol ; 290(1): L66-74, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16199434

RESUMO

Lysophosphatidic acid (LPA) is a membrane-derived lysophospholipid with wide-ranging effects on multiple lung cells including airway epithelial and smooth muscle cells. LPA can augment migration and cytokine synthesis in lymphocytes, but its potential effects on Th2 cytokines have not been well studied. We examined the effects of physiological concentrations of LPA on IL-13 gene expression in human T cells. The Jurkat T cell line and human peripheral blood CD4+ T cells were incubated with LPA alone or with 1) pharmacological agonists of different signaling pathways, or 2) antibodies directed against the T cell receptor complex and costimulatory molecules. Luciferase-based reporter constructs driven by different lengths of the human IL-13 promoter were transfected by electroporation in Jurkat cells treated with and without LPA. The effects of LPA on IL-13 mRNA stability were examined using actinomycin D to halt ongoing transcription. Expression of mRNA encoding LPA2 and LPP-1 increased with T cell activation. LPA augmented IL-13 secretion under conditions of submaximal T cell activation. This was observed using pharmacological agonists activating intracellular calcium-, PKC-, and cAMP-dependent signaling pathways, as well as antibodies directed against CD3 and CD28. LPA only slightly prolonged IL-13 mRNA half-life in submaximally stimulated Jurkat cells. In contrast, LPA significantly enhanced transcriptional activation of the IL-13 promoter via regulatory elements contained within proximal 312 bp. The effects of LPA on IL-13 promoter activation appeared to be distinct from those mediated by GATA-3. LPA can augment IL-13 gene expression in T cells, especially under conditions of submaximal activation.


Assuntos
Interleucina-13/metabolismo , Lisofosfolipídeos/farmacologia , Regiões Promotoras Genéticas/efeitos dos fármacos , Linfócitos T/fisiologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Calcimicina/farmacologia , Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-13/genética , Ionóforos/farmacologia , Células Jurkat , Lisofosfolipídeos/metabolismo , Isoformas de Proteínas/metabolismo , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Transcrição Gênica/efeitos dos fármacos
15.
Stem Cells Dev ; 15(6): 797-804, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17253943

RESUMO

Lysophosphatidic acid (LPA) is a biologically active lysophospholipid that can regulate immune activation. LPA can activate T cells and dendritic cells (DCs), but the effects of LPA on the ability of DCs to influence T cell polarization are not well understood. Human monocyte-derived DCs were differentiated in vitro in the presence of interleukin-4 (IL-4) and granulocyte-macrophage colonystimulating factor (GM-CSF), and matured with LPA and lipopolysaccharide (LPS) alone or in combination. DC activation was monitored by analyzing cell-surface expression of co-stimulatory receptors and cytokine production. The ability of DCs to influence T cell activation was determined using two models of DC:T cell co-culture. Maturation with LPS induced dose-dependent DC activation characterized by enhanced expression of co-stimulatory molecules (e.g., CD86) and production of cytokines including IL-6 and IL-10. Co-incubation with LPA attenuated the LPS-induced production of IL-6, without significantly affecting IL-10 secretion or the ability of DC to promote T cell proliferation. DCs matured in the presence of both LPA and LPS enhanced the production of interferon-gamma (IFN-gamma) when co-cultured with allogeneic T cells, compared with DC matured by LPS alone. Similar results were found using a model of allogeneic naïve T cell differentiation, where LPA- plus LPS-matured DC enhanced IFN-gamma as well as IL-4 secretion after restimulation. Lysophosphatidic acid fine-tunes the effects of LPS on human myeloid DC maturation, but does not exert a dominant effect on the ability of DC to influence Th cell polarization.


Assuntos
Células Dendríticas/fisiologia , Lisofosfolipídeos/farmacologia , Monócitos/fisiologia , Receptores de Ácidos Lisofosfatídicos/fisiologia , Sequência de Aminoácidos , Animais , Técnicas de Cocultura , Sequência Conservada , Citocinas/metabolismo , Células Dendríticas/citologia , Células Dendríticas/efeitos dos fármacos , Humanos , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Dados de Sequência Molecular , Monócitos/efeitos dos fármacos , Linfócitos T/citologia , Linfócitos T/imunologia
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