RESUMO
Pregnant women with preeclampsia (PE) present a shift in the immune response to an inflammatory profile. This deviation could be due to the interaction of tumor necrosis factor (TNF) with TNFR1 and TNFR2 receptors, besides the failure in modulation of inflammation regulatory mechanisms. This study evaluated the effects of progesterone on the expression of TNFR1 and TNFR2 by Jurkat cells after stimulation with plasma from PE and normotensive (NT) pregnant women. Jurkat cells were cultured with or without progesterone in a medium containing 20% (v/v) plasma from PE or NT women. The expression of TNF receptors was evaluated by flow cytometry. The concentration of soluble forms of TNF receptors and cytokines was determined in culture supernatant and plasma by ELISA. The plasma of PE women showed significantly higher concentrations of sTNFR1 and TNF and lower concentrations of sTNFR2 compared to the NT group. TNFR1 receptor expression was increased in Jurkat cells, while TNFR2 was decreased after culture with PE plasma when compared with Jurkat cells cultured with progesterone and plasma from NT women. The concentration of sTNFR1, TNF, and IL-10 in the culture supernatant of Jurkat cells was increased after culture with PE plasma, while the sTNFR2 receptor was decreased when compared to the NT group. Results demonstrate that in preeclamptic women a systemic inflammation occurs with an increase of inflammatory molecules, and progesterone may have a modulating effect on the expression of TNF receptors, shifting Jurkat cells towards an anti-inflammatory profile with greater expression of TNFR2.
Assuntos
Pré-Eclâmpsia , Progesterona , Receptores Tipo II do Fator de Necrose Tumoral , Receptores Tipo I de Fatores de Necrose Tumoral , Feminino , Humanos , Gravidez , Células Cultivadas , Inflamação/metabolismo , Células Jurkat , Pré-Eclâmpsia/metabolismo , Gestantes , Progesterona/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Degranulation mediated killing mechanism by NK cells is dependent on store-operated Ca2+ entry (SOCE) and has optimum at moderate intracellular Ca2+ elevations so that partial block of SOCE optimizes the killing process. In this study, we tested the effect of the selective blocker of KCa3.1 channel NS6180 on SOCE and the killing efficiency of NK cells from healthy donors and NK-92 cells against T-ALL cell line Jurkat. Patch-clamp analysis showed that only one-quarter of resting NK cells functionally express KCa3.1 current, which increases 3-fold after activation by interleukins 15 and 2. Nevertheless, blockage of KCa3.1 significantly reduced SOCE and intracellular Ca2+ rise induced by IL-15 or target cell recognition. NS6180 (1 µM) decreased NK degranulation at zero time of coculture with Jurkat cells but already after 1 h, the degranulation reached the same level as in the control. Monitoring of target cell death by flow cytometry and confocal microscopy demonstrated that NS6180 significantly improved the killing ability of NK cells after 1 h in coculture with Jurkat cells and increased the Jurkat cell fraction with apoptotic and necrotic markers. Our data evidence a strong dependence of SOCE on KCa3.1 activity in NK cells and that KCa3.1 specific block can improve NK cytotoxicity.
Assuntos
Antineoplásicos , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Tiazinas , Humanos , Células Jurkat , Células Matadoras NaturaisRESUMO
Cigarette smoke (CS) affects immune functions, leading to severe outcomes in smokers. Robust evidence addresses the immunotoxic effects of combustible tobacco products. As heat-not-burn tobacco products (HNBT) vaporize lower levels of combustible products, we here compared the effects of cigarette smoke (CS) and HNBT vapor on Jurkat T cells. Cells were exposed to air, conventional cigarettes or heatsticks of HNBT for 30 min and were stimulated or not with phorbol myristate acetate (PMA). Cell viability, proliferation, reactive oxygen species (ROS) production, 8-OHdG, MAP-kinases and nuclear factor κB (NFκB) activation and metallothionein expression (MTs) were assessed by flow cytometry; nitric oxide (NO) and cytokine levels were measured by Griess reaction and ELISA, respectively. Levels of metals in the exposure chambers were quantified by inductively coupled plasma mass spectrometry. MT expressions were quantified by immunohistochemistry in the lungs and liver of C57Bl/6 mice exposed to CS, HNBT or air (1 h, twice a day for five days: via inhalation). While both CS and HBNT exposures increased cell death, CS led to a higher number of necrotic cells, increased the production of ROS, NO, inflammatory cytokines and MTs when compared to HNBT-exposed cells, and led to a higher expression of MTs in mice. CS released higher amounts of metals. CS and HNBT exposures decreased PMA-induced interleukin-2 (IL-2) secretion and impaired Jurkat proliferation, effects also seen in cells exposed to nicotine. Although HNBT vapor does not activate T cells as CS does, exposure to both HNBT and CS suppressed proliferation and IL-2 release, a pivotal cytokine involved with T cell proliferation and tolerance, and this effect may be related to nicotine content in both products.
Assuntos
Nicotiana , Produtos do Tabaco , Animais , Temperatura Alta , Camundongos , Fumaça/efeitos adversos , FumarRESUMO
In our previous work, lupeol was isolated from aerial parts of V. scorpioides and modified by semisynthetic approach. The purpose of this study was to investigate the cytotoxicity of lupeol and its derivatives previously prepared on the human K562 acute myeloid leukemia cell and human Jurkat acute lymphoid leukemia cell in vitro. Compounds 3ß-hydroxylup-20(29)-en-30-al (2), lup-20(30)-en-3ß,29-diol (3), 3ß-acetoxylup-20(29)-en-30-al (5) and 3ß-acetoxy-30-hydroxylup-20(29)-ene (6) presented cytotoxicity with IC50 ranging from 11.72 to 56.15 µM at 24 h of incubation for both cell lines. Most of the active compounds (3, 5 and 6) were selective to leukemia cells, in compare with healthy cells. The hemolysis assay showed high blood compatibility of the cytotoxic lupeol derivatives which makes possible an intravenous administration of these compounds aiming to the potential to development of anti-leukemic drugs.
Assuntos
Extratos Vegetais , Humanos , Células Jurkat , Triterpenos Pentacíclicos/farmacologiaRESUMO
Nonviral gene delivery vectors are attractive candidates compared to viral ones due to their lower cytotoxicity and immunogenicity. However, their efficacy still requires improvement. Major challenges are the effective complexation and protection of the DNA cargo and the intracellular dissociation of the polyplexes at the site of action. It is commonly accepted that polymer architecture and chemistry influence polyplex characteristics and have an impact on the transfection mechanism. We developed a library of biocompatible copolymers based on methoxy poly(ethylene glycol) and a hydrophobic block of poly(ε-caprolactone-co-propargyl carbonate) grafted with a predetermined number of poly(2-(dimethylamino)ethyl methacrylate) segments. Such copolymers could efficiently deliver their cargo even in the presence of serum proteins and to various "difficult to transfect" cells, thereby outperforming the current gold standard 25 kDa linear poly(ethylenimine). Statistical correlation analysis shows that an optimization of the transfection in the case of copolymers combining several interactive functions benefits from treatment as a multiparameter problem.
Assuntos
Portadores de Fármacos/química , Poliésteres/química , Polietilenoglicóis/química , DNA/química , DNA/metabolismo , Portadores de Fármacos/síntese química , Portadores de Fármacos/toxicidade , Expressão Gênica/fisiologia , Células HEK293 , Humanos , Células Jurkat , Poliésteres/síntese química , Poliésteres/toxicidade , Polietilenoglicóis/síntese química , Polietilenoglicóis/toxicidade , Transfecção/métodosRESUMO
Antimicrobial peptides (AMPs) constitute a diverse family of peptides with the ability to protect their host against microbial infections. In addition to their ability to kill microorganisms, several AMPs also exhibit selective cytotoxicity towards cancer cells and are collectively referred to as anticancer peptides (ACPs). Here a large library of AMPs, mainly derived from the porcine cathelicidin peptide, tritrpticin (VRRFPWWWPFLRR), were assessed for their anticancer activity against the Jurkat T cell leukemia line. These anticancer potencies were compared to the cytotoxicity of the peptides towards normal cells isolated from healthy donors, namely peripheral blood mononuclear cells (PBMCs) and red blood cells (RBCs; where hemolytic activity was assessed). Among the active tritrpticin derivatives, substitution of Arg by Lys enhanced the selectivity of the peptides towards Jurkat cells when compared to PBMCs. Additionally, the side chain length of the Lys residues was also optimized to further enhance the tritrpticin ACP selectivity at low concentrations. The mechanism of action of the peptides with high selectivity involved the permeabilization of the cytoplasmic membrane of Jurkat cells, without formation of apoptotic bodies. The incorporation of non-natural Lys-based cationic amino acids could provide a new strategy to improve the selectivity of other synthetic ACPs to enhance their potential for therapeutic use against leukemia cells.
Assuntos
Peptídeos Catiônicos Antimicrobianos/genética , Antineoplásicos/farmacologia , Oligopeptídeos/genética , Peptídeos/genética , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Antineoplásicos/química , Dicroísmo Circular , Eritrócitos/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Oligopeptídeos/química , Peptídeos/química , Peptídeos/farmacologia , Suínos , CatelicidinasRESUMO
The effect of Micrurus mipartitus snake venom as a therapeutic alternative for T-acute lymphoblastic leukemia (ALL) is still unknown. This study was aimed to evaluate the cytotoxic effect of M. mipartitus snake venom and a new L-amino acid oxidase (LAAO), named MipLAAO, on human peripheral blood lymphocytes (PBL) and on T-ALL cells (Jurkat), and its mechanism of action. PBL and Jurkat cells were treated with venom and MipLAAO, and morphological changes in the cell nucleus/DNA, mitochondrial membrane potential, levels of intracellular reactive oxygen species and cellular apoptosis markers were determined by fluorescence microscopy, flow cytometry and pharmacological inhibition. Venom and MipLAAO induced apoptotic cell death in Jurkat cells, but not in PBL, in a dose-response manner. Additionally, venom and MipLAAO increased dichlorofluorescein fluorescence intensity, indicative of H2O2 production, increased DJ-1 Cys106-sulfonate, as a marker of intracellular stress and induced the up-regulation of PUMA, p53 and phosphorylation of c-JUN. Additionally, it increased the expression of apoptotic CASPASE-3. In conclusion, M. mipartitus venom and MipLAAO selectively induces apoptosis in Jurkat cells through a H2O2-mediated signaling pathway dependent mostly on CASPASE-3 pathway. Our findings support the potential use of M. mipartitus snake venom compounds as a potential treatment for T-ALL.
Assuntos
Apoptose/efeitos dos fármacos , Cobras Corais , L-Aminoácido Oxidase/isolamento & purificação , L-Aminoácido Oxidase/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Venenos de Serpentes/enzimologia , Animais , Biomarcadores Tumorais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Humanos , Peróxido de Hidrogênio/metabolismo , Células Jurkat , L-Aminoácido Oxidase/química , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras , Espécies Reativas de OxigênioRESUMO
Estrogens demonstrate biological activity in numerous organ systems, including the immune system, and exert their effects through estrogen receptors (ER) of two types: intracellular ERα and ERß that activate transcriptional factors and membrane G protein-coupled ER GPER. The latter is capable to mediate fast activation of cytosolic signaling pathways, influencing transcriptional events in response to estrogens. Tamoxifen (TAM), widely used in chemotherapy of ERα-positive breast cancer, is considered as an ERα antagonist and GPER agonist. TAM was shown to possess "off-target" cytotoxicity, not related to ER in various tumor types. The present work was designed to study biological effects of TAM on the glucocorticoid (GC)-resistant cell line Jurkat, derived from acute lymphoblastic leukemia of T lineage (T-ALL). We have shown that T-ALL cell lines, in contrast to healthy T cells, express only GPER, but not ERα or ERß. TAM compromised mitochondrial function and reduced the viability and proliferation of Jurkat cells. Additionally, TAM induced autophagy in a GPER-dependent manner. Gene expression profiling revealed the up-regulation of autophagy-related gene ATG5. Interestingly, TAM sensitized Jurkat cells to dexamethasone (DEX) treatment, which may be related to its capacity to cause autophagy. We suggest that TAM-based adjuvant therapy may represent a novel strategy in T-ALL patients handling.
Assuntos
Antineoplásicos Hormonais/farmacologia , Autofagia/efeitos dos fármacos , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/genética , Regulação Neoplásica da Expressão Gênica , Receptores de Estrogênio/genética , Receptores Acoplados a Proteínas G/genética , Tamoxifeno/farmacologia , Autofagia/genética , Proteína 5 Relacionada à Autofagia/agonistas , Proteína 5 Relacionada à Autofagia/genética , Proteína 5 Relacionada à Autofagia/metabolismo , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dexametasona/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/antagonistas & inibidores , Receptor beta de Estrogênio/metabolismo , Perfilação da Expressão Gênica , Humanos , Células Jurkat , Ativação Linfocitária/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Cultura Primária de Células , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/metabolismo , Transdução de SinaisRESUMO
The HIV transactivator protein (Tat) is a multifunctional protein that plays a critical role in viral replication and contributes to several pathological symptoms of HIV-1 infection, which has the loss of CD4+ T lymphocytes as one of its hallmark features. It has been shown that endoplasmic reticulum (ER) stress, including viral infections, is implicated in cellular dysfunction and cell death through activation of the unfolded protein response (UPR). Here, we demonstrate that the bystander stimulus of Tat on Jurkat cells resulted in time-dependent overexpression of major UPR markers including ER chaperone BiP, ER stress sensors ATF6, PERK, and IRE1, as well as an increase in levels of downstream mediators eIF2α, ATF4, XBP-1, and proapoptotic factors CHOP, GADD34, and BIM. This upregulation of UPR mediators was accompanied by decreased cell viability and increased apoptosis as evidenced by blue trypan dye exclusion and flow cytometry assays, respectively. Furthermore, we found that the Tat-associated apoptosis of Jurkat cells led to the loss of mitochondrial membrane potential and caspase-12 and -3 activation. Taken together, these results suggest that the exposure of HIV-1 Tat leads to ER stress/UPR triggering which in turn contributes to apoptotic death in Jurkat cells. SIGNIFICANCE OF THE STUDY: In the present work, we provide a substantial insight into the link between ER impairment and apoptotic death following a bystander HIV Tat stimulus, revealing an underlying ER-mediated apoptotic mechanism which could explain the continuous depletion of uninfected CD4+ T lymphocytes observed in HIV-related disease. Our findings reinforce the relevance of ER stress molecular responses in the course of HIV infection and may afford valuable information for the development of new therapeutic strategies to avoid CD4+ T lymphocyte loss and other disorders induced by circulant Tat.
Assuntos
Apoptose , Efeito Espectador , Resposta a Proteínas não Dobradas , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismo , Linfócitos T CD4-Positivos/imunologia , Sobrevivência Celular , Células Cultivadas , Estresse do Retículo Endoplasmático/imunologia , HIV/imunologia , Humanos , Células Jurkat , Desdobramento de ProteínaRESUMO
Inositol hexaphosphate (InsP6) is present in cereals, legumes, nuts and seed oils and is biologically active against some tumor and cancer cells. Herein, this study aimed at evaluating the cellular toxicity, antiproliferative activity and effects on cell cycle progression of free InsP6 and InsP6-Ni(II) of leukemic T (Jurkat) and normal human cells. Treatments with InsP6 at concentrations between 1.0 and 4.0mM significantly decreased the viability of Jurkat cells, but showed no cytotoxic effect on normal human lymphocytes. Treatment with InsP6-Ni(II) complex at concentrations between 0.05 and 0.30 mM showed an anti-proliferative dose and a time-dependent effect, with significantly reduced cell viability of Jurkat cells but showed no cytotoxic effect on normal human lymphocytes as compared to the control. Ni(II) free ion was toxic to normal cells while InsP6-Ni(II) had no cytotoxic effect. The InsP6-Ni(II) complex potentiated (up to 10×) the antiproliferative effect of free InsP6 on Jurkat cells. The cytometric flow assay showed that InsP6 led to an accumulation of cells in the G0/G1 phase of the cell cycle, accompanied by a decrease in the number of cells in S and G2/M phases, whereas InsP6-Ni(II) has led to an accumulation of cells in the S and G2/M phases. Our findings showed that InsP6-Ni(II) potentiates cytotoxic effects of InsP6 on Jurkat cells and may be a potential adjuvant in the treatment of cancer.
Assuntos
Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Níquel/química , Ácido Fítico/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Ciclo Celular/efeitos dos fármacos , Humanos , Células Jurkat , Ácido Fítico/químicaRESUMO
In order to assess the anticancer action of extracts obtained by latex from Calotropis procera and Pedilanthus tithymaloides, samples were collected from adult plants. Soluble proteins were extracted with 16 uL of 50 mM sodium acetate pH 5/ug integral latex and centrifugation at 16,000 x g for 15 min, the supernatant was named "latex crude extract" (LCE). The "latex methanolic extract" (LME) was obtained on dried latex. Both extracts were tested in vitro by cytotoxic and cytostatic activity in Jurkat cell cultures. Cellular viability, proliferation, necrosis and apoptosis were evaluated. LCE and LME of C. procera were found with cytotoxic and cytostatic activity after 24 incubation hours (p < 0,05) with doses from 1ug/mL. The LCE and LME of P. tithymaloides presented cytotoxic effect (p < 0,05) from 50 ug/mL and from 1ug/mL, respectively.
Con el objetivo de evaluar el potencial anticanceroso de extractos de látex de Calotropis procera y Pedilanthus tithymaloides se colectaron muestras de plantas adultas. Las proteínas solubles fueron extraídas con 16 uL de acetato de sodio 50 mM pH 5/ug de látex integral y centrifugación a 16.000 x g durante 15 min, denominándose al sobrenadante extracto crudo de látex (ECL). El extracto metanólico de látex (EML) se obtuvo sobre látex deshidratado. Ambos extractos fueron probados en su actividad citotóxica y citostática in vitro sobre cultivos de células Jurkat. Se realizaron estudios de viabilidad, proliferación, necrosis y apoptosis celular. El ECL y el EML de C. procera presentaron actividad citotóxica y citostática después de 24 y 48 horas de incubación (p < 0,05) con dosis desde 1 ug/mL. Los ECL y EML de P. tithymaloides presentaron efectos citotóxicos (p < 0,05) a partir de 50 ug/mL y desde 1 ug/mL respectivamente.