RESUMO
Biodiesel, derived from alkyl esters of vegetable oils or animal fats, has gained prominence as a greener alternative to diesel due to its reduced particle mass. However, it remains debatable whether biodiesel exposure has more severe health issues than diesel. This study performed high-resolution mass spectrometry to examine the detailed particle chemical compositions and lipidomics analysis of human lung epithelial cells treated with emissions from biodiesel and diesel fuels. Results show the presence of the peak substances of CHO compounds in biodiesel combustion that contain a phthalate ester (PAEs) structure (e.g., n-amyl isoamyl phthalate and diisobutyl phthalate). PAEs have emerged as persistent organic pollutants across various environmental media and are known to possess endocrine-disrupting properties in the environment. We further observed that biodiesel prevents triglyceride storage compared to diesel and inhibits triglycerides from becoming phospholipids, particularly with increased phosphatidylglycerols (PGs) and phosphatidylethanolamines (PEs), which potentially could lead to a higher probability of cancer metastasis.
Assuntos
Poluentes Atmosféricos , Emissões de Veículos , Animais , Humanos , Emissões de Veículos/análise , Biocombustíveis/análise , Metabolismo dos Lipídeos , Gasolina/análise , Poluentes Atmosféricos/análiseRESUMO
Iodide (I-) is crucial to thyroid function, and its regulation in thyrocytes involves ion transporters and reactive oxygen species (ROS). However, the extent of 2Cl-/H+ exchanger (ClC-3) involvement in the iodide (I-) efflux from thyrocytes remains unclear. Therefore, we examined the effects of ClC-3 on I- efflux. ClC-3 expression was found to significantly alter the serum TT3 and TT4 concentrations in mice. We further found that excess I- stimulation affected ClC-3 expression, distribution, and I- efflux in FRTL-5 cells. Immunofluorescence analyses indicated that ClC-3 mainly accumulated in the cell membrane and co-localized with ß-tubulins after 24â h of excess I- treatment, and that this process depended on ROS production. Thus, ClC-3 may be involved in I- efflux at the apical pole of thyrocytes via excess I--induced ROS production and ß-tubulin polymerization. Our results reveal novel insights into the role of ClC-3 in I- transport and thyroid function.
Assuntos
Canais de Cloreto/metabolismo , Células Epiteliais da Tireoide , Animais , Transporte Biológico , Iodetos , Camundongos , Prótons , Espécies Reativas de Oxigênio , Tubulina (Proteína)RESUMO
Wound exudate holds great clinical and research potential in wound repair via paracrine signaling. In essence, exudate is modified serum that contains a high concentration of exosomes. The aim of this study was to investigate the role of serum-derived exosomes in scald wound healing of NIH mice skin and to explore the underlying mechanisms. Hence, we constructed a deep second-degree scald model in NIH mice, testing the benefits of exosomes in the scald wound healing. The scratch wound assay, apoptosis assay and MTT assay were conducted to assess the effects of serum-derived exosomes on migration, apoptosis and proliferation of HaCaT cells and fibroblasts. Our results showed that serum-derived exosomes injected subcutaneously entered cells and effectively accelerated wound healing processes in mice. Additionally, serum-derived exosomes optimized functions of cells related to skin injury repair by stimulating fibroblast proliferation, promoting HaCaT cell migration, and suppressing apoptosis of HaCaT cells induced by heat stress. Further study revealed that serum-derived exosomes enhanced phosphorylation of the serine-threonine kinase Akt in scalded skin tissue. These results suggest a potential clinical use of serum-derived exosomes for treating skin scald.
Assuntos
Exossomos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Cicatrização/efeitos dos fármacos , Animais , Produtos Biológicos/farmacologia , Linhagem Celular , Masculino , Camundongos , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/química , Ratos Sprague-Dawley , Soro/química , Pele/citologia , Pele/efeitos dos fármacos , Pele/lesõesRESUMO
Serine-52 (Ser52) is the major physiologic site of keratin 18 (K18) phosphorylation. Here, we report that serine-52 phosphorylated K18 (phospho-Ser52 K18) accumulated on centrosomes in a cell cycle-dependent manner. Moreover, we found that phospho-Ser52 K18 was located at the proximal end of the mother centriole. Transfection with the K18 Ser52 â Ala (K18 S52A) mutant prevented centriole localization of phospho-Ser52 K18 and resulted in separation of the mother-daughter centrioles. Inhibition of microtubule polymerization led to the disappearance of aggregated phospho-Ser52 K18 on the centrosome; removal of inhibitors resulted in reaccumulation of phospho-Ser52 K18 in microtubule-organizing centers. Transfection with a K18 S52A mutant inhibited microtubule nucleation. These results reveal a cell cycle-dependent change in centrosome localization of phospho-Ser52 k18 and strongly suggest that the phosphorylation status of Ser52 K18 of mother centrioles plays a critical role in maintaining a tight engagement between mother and daughter centrioles and also contributes to microtubule nucleation.
Assuntos
Ciclo Celular , Centríolos/metabolismo , Queratina-18/metabolismo , Microtúbulos/metabolismo , Serina/metabolismo , Animais , Células Cultivadas , Células HeLa , Humanos , Camundongos , Células NIH 3T3 , FosforilaçãoRESUMO
Chloride channel-3 (ClC-3), a member of the ClC family of voltage-gated Cl- channels, is involved in the resistance of tumor cells to chemotherapeutic drugs. Here, we report a new mechanism for ClC-3 in mediating multidrug resistance (MDR). ClC-3 was highly expressed in the P-glycoprotein (P-gp)-dependent human lung adenocarcinoma cell line (A549)/paclitaxel (PTX) and the human breast carcinoma cell line (MCF-7)/doxorubicin (DOX) resistant cells. Changes in the ClC-3 expression resulted in the development of drug resistance in formerly drug-sensitive A549 or MCF-7 cells, and drug sensitivity in formerly drug-resistant A549/Taxol and MCF-7/DOX cells. Double transgenic MMTV-PyMT/CLCN3 mice with spontaneous mammary cancer and ClC-3 overexpression demonstrated drug resistance to PTX and DOX. ClC-3 expression upregulated the expression of MDR1 messenger RNA and P-gp by activating the nuclear factor-κB (NF-κB)-signaling pathway. These data suggest that ClC-3 expression in cancer cells induces MDR by upregulating NF-κB-signaling-dependent P-gp expression involving another new mechanism for ClC-3 in the development of drug resistance of cancers.
Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Neoplasias da Mama/metabolismo , Canais de Cloreto/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Células MCF-7 , NF-kappa B/metabolismo , Ativação Transcricional/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologiaRESUMO
Cisplatin-based concomitant chemoradiotherapy is considered as the standard treatment for locally advanced nasopharyngeal carcinoma patients. However, the curative efficacy of cisplatin-based chemotherapy is limited because of the occurrence of cisplatin resistance. Some researches indicate that activating the volume-sensitive Cl(-) channel might be a new strategy for the reduction of cisplatin resistance. However, little is known about the activation pathway of the Cl(-) channels activated by cisplatin. In this study, the cisplatin-activated chloride current was investigated using the whole cell patch-clamp technique in the poorly differentiated nasopharyngeal carcinoma cells (CNE-2Z cells), and the activation pathway of the current was also discussed. The results showed that extracellular application of cisplatin activated a Cl(-) current, showing the properties of significant outward rectification, intracellular ATP dependency, and a selectivity sequence of I(-) > Br(-) > Cl(-) > gluconate, and being inhibited by the Cl(-) channel inhibitors tamoxifen and extracellular ATP. These characteristics are similar to those of the volume-sensitive Cl(-) current in CNE-2Z cells, indicating that cisplatin induces the Cl(-) current by activating the volume-sensitive like chloride channel. The cisplatin-activated current was blocked by suramin (a wide-spectrum purinergic antagonist) and RB2 (a relatively selective P2Y antagonist). In addition, the current was depressed by extracellular application of apyrase. The apoptotic volume decrease induced by cisplatin was also attenuated by RB2. P2Y receptors were expressed in CNE-2Z cells. These results suggest that cisplatin can induce a Cl(-) current by activating volume-sensitive like Cl(-) channels through the P2Y purinoceptor pathway.
Assuntos
Canais de Cloreto/metabolismo , Cisplatino/farmacologia , Neoplasias Nasofaríngeas/metabolismo , Receptores Purinérgicos/metabolismo , Carcinoma , Linhagem Celular Tumoral , Tamanho Celular/efeitos dos fármacos , Células Cultivadas , Canais de Cloreto/efeitos dos fármacos , Imunofluorescência , Humanos , Carcinoma Nasofaríngeo , Técnicas de Patch-ClampRESUMO
Pine needle oil from crude extract of pine needles has been used as an anti-cancer agent in Traditional Chinese Medicine. The α-pinene is a natural compound isolated from pine needle oil which has been shown anti-cancer activity. In previous study, we found that pine needle oil exhibited significant inhibitory effect on hepatoma carcinoma BEL-7402 cells. In this study, we investigate the inhibition of α-pinene on hepatoma carcinoma BEL-7402 cells in vitro and in vivo and further explore the mechanism. The results show that liver cancer cell growth was inhibited obviously with inhibitory rate of 79.3% in vitro and 69.1% in vivo, Chk1 and Chk2 levels were upregulated, CyclinB, CDC25 and CDK1 levels were downregulated.
Assuntos
Antineoplásicos Fitogênicos , Carcinoma Hepatocelular/patologia , Pontos de Checagem da Fase G2 do Ciclo Celular/genética , Neoplasias Hepáticas/patologia , Pontos de Checagem da Fase M do Ciclo Celular/genética , Monoterpenos/farmacologia , Pinus/química , Óleos de Plantas/química , Animais , Monoterpenos Bicíclicos , Proteína Quinase CDC2 , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Quinase 1 do Ponto de Checagem , Quinase do Ponto de Checagem 2/metabolismo , Ciclina B/metabolismo , Quinases Ciclina-Dependentes/metabolismo , Regulação para Baixo/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Camundongos Nus , Monoterpenos/isolamento & purificação , Transplante de Neoplasias , Fitoterapia , Proteínas Quinases/metabolismo , Células Tumorais Cultivadas , Regulação para Cima/efeitos dos fármacosRESUMO
Philadelphia chromosome positive (Ph+) acute lymphoblastic leukemia (ALL) cells are insensitive to BCR-ABL tyrosine kinase inhibitor imatinib, the underlying mechanisms remain largely unknown. Here, we showed that imatinib treatment induced significant upregulation of miR-21 and downregulation of PTEN in Ph+ ALL cell line Sup-b15. Transient inhibition of miR-21 resulted in increased apoptosis, PTEN upregulation and AKT dephosphorylation, whereas ectopic overexpression of miR-21 further conferred imatinib resistance. Furthermore, knockdown of PTEN protected the cells from imatinib-induced apoptosis achieved by inhibition of miR-21. Additionally, PI3K inhibitors also notably enhanced the effects of imatinib on Sup-b15 cells and primary Ph+ ALL cells similar to miR-21 inhibitor. Therefore, miR-21 contributes to imatinib resistance in Ph+ ALL cells and antagonizing miR-21 demonstrates therapeutic potential by sensitizing the malignancy to imatinib therapy.
Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Mesilato de Imatinib/farmacologia , MicroRNAs/genética , Oligonucleotídeos/farmacologia , PTEN Fosfo-Hidrolase/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Antagomirs , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Inibidores de Fosfoinositídeo-3 Quinase , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Inibidores de Proteínas Quinases/farmacologia , Interferência de RNA , RNA Interferente Pequeno/genética , Regulação para Cima/efeitos dos fármacosRESUMO
Tamoxifen is a triphenylethylene non-steroidal antiestrogen anticancer agent. It also shows inhibitory effects on metastasis of estrogen receptor (EsR)-independent tumors, but the underlying mechanism is unclear. It was demonstrated in this study that, in EsR-negative and highly metastatic human hepatocellular carcinoma MHCC97H cells, tamoxifen-inhibited cell migration, volume-activated Cl(-) currents (I(Cl,vol)) and regulatory volume decrease (RVD) in a concentration-dependent manner with a similar IC(50). Analysis of the relationships between migration, I(Cl,vol) and RVD showed that cell migration was positively correlated with I(Cl,vol) and RVD. Knockdown of the expression of ClC-3 Cl(-) channel proteins by ClC-3 shRNA or siRNA inhibited I(Cl,vol), and cell migration, and these inhibitory effects could not be increased further by addition of tamoxifen in the medium. The results suggest that knockdown of ClC-3 expression may deplete the effects of tamoxifen; tamoxifen may inhibit cell migration by modulating I(Cl,vol) and cell volume. Moreover, tamoxifen decreased the activity of protein kinase C (PKC) and the effects were reversed by the PKC activator PMA. Activation of PKC by PMA could competitively downregulate the inhibitory effects of tamoxifen on I(Cl,vol). PMA promoted cell migration, and knockdown of ClC-3 expression by ClC-3 siRNA abolished the PMA effect on cell migration. The results suggest that tamoxifen may inhibit I(Cl,vol) by suppressing PKC activation; I(Cl,vol) may be an EsR-independent target for tamoxifen in the anti-metastatic action on cancers, especially on EsR-negative cancers. The finding may have an implication in the clinical use of tamoxifen in the treatments of both EsR-positive and EsR-negative cancers.
Assuntos
Carcinoma Hepatocelular/metabolismo , Movimento Celular/efeitos dos fármacos , Canais de Cloreto , Neoplasias Hepáticas/metabolismo , Tamoxifeno/farmacologia , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Tamanho Celular/efeitos dos fármacos , Canais de Cloreto/antagonistas & inibidores , Canais de Cloreto/genética , Canais de Cloreto/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Metástase Neoplásica , RNA Interferente Pequeno , Receptores de Estrogênio/metabolismo , Acetato de Tetradecanoilforbol/análogos & derivados , Acetato de Tetradecanoilforbol/farmacologiaRESUMO
The cytotoxicities of two oxovanadium complexes, VOI [VO(satsc)(phen)] (satsc = salicylaldehyde thiosemicarbazone, phen = 1,10-phenanthroline) and VOII [VO(3,5-dibrsatsc)(phen)](3,5-dibrsatsc = 3,5-dibromosalicylaldehyde thiosemicarbazone), were studied by performing MTT assays on human hepatoma cell lines BEL-7402, HUH-7 and HepG2. The results showed that both the VOI and VOII complexes possess significant anti-proliferative effects. In addition, the anti-proliferative mechanism of the complexes was analyzed by cell cycle analysis and an apoptosis assay and by detecting the mitochondrial membrane potential (delta psi m). The experimental results showed that the complexes can cause a G0/G1 phase cell cycle arrest and can significantly decrease delta psi m, causing depolarization of the mitochondrial membrane. Notably, the two complexes induced apoptosis in BEL-7402 cells and displayed typical morphological apoptotic characteristics. The cytotoxicities of the VOII complex are significantly stronger than that of the VOI complex, suggesting that the cytotoxic effects of oxovanadium complexes may be associated with the electronic effects of the complexes.
Assuntos
Antineoplásicos/farmacologia , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Compostos Organometálicos/farmacologia , Vanádio/farmacologia , Animais , Anexina A5 , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Corantes , Ensaios de Seleção de Medicamentos Antitumorais , Fluoresceína-5-Isotiocianato , Corantes Fluorescentes , Fase G1/efeitos dos fármacos , Humanos , Neoplasias Hepáticas Experimentais/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Microscopia de Fluorescência , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Sais de Tetrazólio , TiazóisRESUMO
Identifying the key factors mediating the progression from hypertension to cardiac hypertrophy is critically important for developing a strategy to protect against heart failure. Serum exosomes have been revealed to be involved in the development of cardiovascular disease. In the current study, we found that either serum or serum exosomes derived from SHR induced hypertrophy in H9c2 cardiomyocytes. SHR Exo injection through the tail vein for 8 weeks induced left ventricular wall thickening and decreased cardiac function in C57BL/6 mice. SHR Exo carried the renin-angiotensin system (RAS) proteins AGT, renin, and ACE into cardiomyocytes, which increased the autocrine secretion of Ang II. Moreover, the AT1-type receptor antagonist telmisartan prevented hypertrophy of H9c2 cells induced by SHR Exo.These results identified a novel role of exosomes derived from SHR serum in cardiac hypertrophy and revealed that SHR Exo induced cardiac hypertrophy by carrying AGT, renin, and ACE proteins into cardiomyocytes to increase their autocrine secretion of Ang II. The emergence of this new mechanism will help us better understand how hypertension progresses to cardiac hypertrophy.
Assuntos
Exossomos , Hipertensão , Ratos , Camundongos , Animais , Angiotensina II/metabolismo , Ratos Endogâmicos SHR , Miócitos Cardíacos/metabolismo , Renina/metabolismo , Exossomos/metabolismo , Camundongos Endogâmicos C57BL , Cardiomegalia/induzido quimicamente , Cardiomegalia/metabolismo , Sistema Renina-Angiotensina , Hipertensão/metabolismoRESUMO
Volume-activated chloride channels have been studied by us extensively in human nasopharyngeal carcinoma cells. However, the chloride channels in the counterpart of the carcinoma cells have not been investigated. In this study, volume-activated chloride currents (I(cl,vol)) were characterized in normal fetal human nasopharyngeal epithelial cells using the whole-cell patch-clamp technique. Under isotonic conditions, nasopharyngeal epithelial cells displayed only a weak background current. Exposure to 47% hypotonic solution activated a volume-sensitive current. The reversal potential of the current was close to the calculated equilibrium potential for Cl(-). The peak values of the hypotonicity-activated current at +80 mV ranged from 0.82 to 2.71 nA in 23 cells. Further analysis indicated that the density of the hypotonicity-activated current in most cells (18/23) was smaller than 60 pA/pF. Only five cells presented a current larger than 60 pA/pF. The hypotonicity-activated current was independent of the exogenous ATP. Chloride channel inhibitors ATP, tamoxifen and 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB), inhibited the current dramatically. The anion permeability of the hypotonicity-activated chloride channels was I(-) > Br(-) > Cl(-) > gluconate. Unexpectedly, in isotonic conditions, ATP (10 mM) activated an inward-rectified current, which had not been observed in the nasopharyngeal carcinoma cells. These results suggest that, under hypotonic challenges, fetal human nasopharyngeal epithelial cells can produce I(cl,vol), which might be involved in cell volume regulation.
Assuntos
Canais de Cloreto/antagonistas & inibidores , Canais de Cloreto/metabolismo , Cloretos/metabolismo , Nasofaringe/fisiologia , Trifosfato de Adenosina/farmacologia , Ânions/metabolismo , Permeabilidade da Membrana Celular/efeitos dos fármacos , Permeabilidade da Membrana Celular/fisiologia , Tamanho Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/fisiologia , Humanos , Soluções Hipotônicas , Soluções Isotônicas , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Nasofaringe/efeitos dos fármacos , Nasofaringe/metabolismo , Nitrobenzoatos/farmacologia , Tamoxifeno/farmacologiaRESUMO
Chloride channel-3 (ClC-3) is suggested to be a component and/or a regulator of the volume-activated Cl(-) channel in the plasma membrane. However, ClC-3 is predominantly located inside cells and the role of intracellular ClC-3 in tumor growth is unknown. In this study, we found that the subcellular distribution of endogenous ClC-3 varied in a cell cycle-dependent manner in HeLa cells. During interphase, ClC-3 was distributed throughout the cell and it accumulated at various positions in different stages. In early G1, ClC-3 was mainly located in the nucleus. In middle G1, ClC-3 gathered around the nuclear periphery as a ring. In late G1, ClC-3 moved back into the nucleus, where it remained throughout S phase. In G2, ClC-3 was concentrated in the cytoplasm. When cells progressed from G2 to the prophase of mitosis, ClC-3 from the cytoplasm translocated into the nucleus. During metaphase and anaphase, ClC-3 was distributed throughout the cell except for around the chromosomes and was aggregated at the spindle poles and in between two chromosomes, respectively. ClC-3 was then again concentrated in the nucleus upon the progression from telophase to cytokinesis. These results reveal a cell cycle-dependent change of the subcellular distribution of ClC-3 and strongly suggest that ClC-3 has nucleocytoplasmic shuttling dynamics that may play key regulatory roles during different stages of the cell cycle in tumor cells.
Assuntos
Ciclo Celular , Canais de Cloreto/metabolismo , Divisão Celular , Canais de Cloreto/análise , Citoplasma/metabolismo , Células HeLa , Humanos , Mitose , Fase SRESUMO
1,10-Phenanthroline has been shown to exhibit anticancer activity. Here, a series of imidazo [4,5f][1,10] phenanthroline derivatives 1-10 were synthesized and their biological activities were further elucidated. We found that 2-(4-Brominephenyl)-imidazo [4,5f][1,10] phenanthroline (compound 3) possessed potent antiproliferation activities again a variety of tumor cell lines using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Flow cytometric analysis revealed that compound 3 induced both through apoptosis and necrosis in human lung adenocarcinoma cell line, A549. Moreover, compound 3 treatment led to up-regulation of IκBα and down-regulation of p65 and c-myc in A549 cells. Taken together, these results suggested that compound 3 inhibited cell proliferation by suppression of NF-κB activity and down-regulation of c-myc gene expression and may be a candidate for further evaluation as a chemopreventive and chemotherapeutic agent for human cancers, especially for lung cancer.
Assuntos
Antineoplásicos/farmacologia , NF-kappa B/metabolismo , Fenantrolinas/química , Proteínas Proto-Oncogênicas c-myc/metabolismo , Adenocarcinoma/tratamento farmacológico , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Citometria de Fluxo/métodos , Humanos , Concentração Inibidora 50 , Neoplasias Pulmonares/tratamento farmacológico , Modelos Químicos , Necrose , Sais de Tetrazólio/farmacologia , Tiazóis/farmacologiaRESUMO
BACKGROUND: Despite emerging research on new treatment strategies, chemotherapy remains one of the most important therapeutic modalities for cancers. Imidazopyridines are important targets in organic chemistry and, given their numerous applications, they are worthy of attention. OBJECTIVE: The objective of this study was to design and synthesize a novel series of imidazo[1,2-a]pyridine-derived compounds and investigate their antitumor effects and the underlying mechanisms. METHODS: Imidazo[1,2-a]pyridine-derived compounds were synthesized with new strategies and conventional methods. The antitumor activities of the new compounds were evaluated by MTT assay. Flow cytometry and immunofluorescence were performed to examine the effects of the most effective antiproliferative compound on cell apoptosis. Western blot analysis was used to assess the expression of apoptotic proteins. RESULTS: Fifty-two new imidazo[1,2-a]pyridine compounds were designed and successfully synthesized. The compound, 1-(imidazo[1,2-a]pyridin-3-yl)-2-(naphthalen-2-yl)ethane-1,2-dione, named La23, showed high potential for suppressing the viability of HeLa cells (IC50 15.32 µM). La23 inhibited cell proliferation by inducing cell apoptosis, and it reduced the mitochondrial membrane potential of HeLa cells. Moreover, treatment with La23 appeared to increase the expression of apoptotic-related protein P53, Bax, cleaved caspase-3, and cytochrome c at a low concentration range. CONCLUSION: The novel imidazo[1,2-a]pyridine compound, La23, was synthesized and it suppressed cell growth by inducing cell apoptosis via the p53/Bax mitochondrial apoptotic pathway.
Assuntos
Antineoplásicos , Proteína Supressora de Tumor p53 , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose , Proliferação de Células , Sobrevivência Celular , Células HeLa , Humanos , Potencial da Membrana Mitocondrial , Piridinas , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/metabolismoRESUMO
Stretch-activated chloride currents (I(Cl,SA) ) have been considered to be a component of volume-activated chloride currents (I(Cl,vol) ) for some time. This is due to a similarity in biophysical and pharmacological properties that involve a membrane curvature-induced mechanism and rearrangement of the cytoskeleton induced by cell swelling or membrane stretch. In the present study, we demonstrated that current density, along with the time taken from the activation of currents to the peak, were significantly different between the two currents, in highly metastatic human hepatocellular carcinoma cells. In addition, the activation of I(Cl,vol) or I(Cl,SA), induced maximally by hypotonic solutions or membrane stretch, respectively, did not affect the following activation of the other one. Moreover, neither inhibition of I(Cl,vol) by sh-ClC-3 transfection, nor functional blocking of I(Cl,vol) by intracellular dialysis of anti-ClC-3 antibody had an effect on the activation and properties of I(Cl,SA). Collectively, our results suggest that I(Cl,SA) is different from I(Cl,vol) in activation mechanism and/or in molecular entity responsible for formation of the currents. ClC-3 is involved in the activation of I(Cl,vol), but not of I(Cl,SA).
Assuntos
Carcinoma Hepatocelular/metabolismo , Forma Celular , Canais de Cloreto/metabolismo , Neoplasias Hepáticas/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Tamanho Celular , Canais de Cloreto/genética , Humanos , Soluções Hipotônicas , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Potenciais da Membrana , Estimulação Física , Interferência de RNA , Fatores de Tempo , TransfecçãoRESUMO
In this study, the activation mechanisms of the background chloride current and the role of the current in maintaining of basal cell volume were investigated in human nasopharyngeal carcinoma CNE-2Z cells. Under isotonic conditions, a background chloride current was recorded by the patch clamp technique. The current presented the properties similar to those of the volume-activated chloride current in the same cell line and was inhibited by chloride channel blockers or by cell shrinkage induced by hypertonic challenges. Extracellular applications of reactive blue 2, a purinergic receptor antagonist, suppressed the background chloride current in a concentration-dependent manner under isotonic conditions. Depletion of extracellular ATP with apyrase or inhibition of ATP release from cells by gadolinium chloride decreased the background current. Extracellular applications of micromolar concentrations of ATP activated a chloride current which was inhibited by chloride channel blockers and hypertonic solutions. Extracellular ATP could also reverse the action of gadolinium chloride. Transfection of CNE-2Z cells with ClC-3 siRNA knocked down expression of ClC-3 proteins, attenuated the background chloride current and prevented activation of the ATP-induced current. Furthermore, knockdown of ClC-3 expression or exposures of cells to ATP (10 mM), the chloride channel blockers 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB) and tamoxifen, or reactive blue 2 increased cell volume under isotonic conditions. The results suggest that ClC-3 protein may be a main component of background chloride channels which can be activated under isotonic conditions by autocrine/paracrine ATP through purinergic receptor pathways; the background current is involved in maintenance of basal cell volume.
Assuntos
Trifosfato de Adenosina/fisiologia , Comunicação Autócrina/fisiologia , Canais de Cloreto/metabolismo , Cloretos/metabolismo , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia , Inibidores da Angiogênese/farmacologia , Comunicação Autócrina/efeitos dos fármacos , Carcinoma , Linhagem Celular Tumoral , Canais de Cloreto/antagonistas & inibidores , Canais de Cloreto/genética , Humanos , Soluções Isotônicas , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Carcinoma Nasofaríngeo , Nitrobenzoatos/farmacologia , Tamoxifeno/farmacologiaRESUMO
Meclicope pteleifolia is a traditional medicinal herb and edible plant in Southeast China. Here, we report the complete chloroplast genome of M. pteleifolia. The chloroplast genome is 159,012 bp in length with 38.33% GC content, containing a small single-copy (SSC) region (18,609 bp), a large single-copy (LSC) region (851 bp), and a pair of inverted repeats (IRs: 27,640 bp each). A total of 131 genes were predicted, including 84 protein-coding genes, 8 ribosomal RNA genes, 37 tRNA genes, and 2 pseudogenes. Phylogenetic analysis based on chloroplast genomes of 17 plant species shows that M. pteleifolia is closest to Zanthoxylum and Casimiroa. These complete chloroplast genomes can be subsequently used for researches of Rutaceae.
RESUMO
T cells play an important role in antitumor immunity. Numbers and function of T cells are controlled by regulating the uptake and utilization of nutrients, and their antitumor activity can be promoted by targeting metabolic pathways. In this review, we highlight the relationship between metabolism and cellular function of T cells. Specifically, we emphasize the metabolic state of tumor-infiltrating T cells and review key pathways that affect the antitumor function of T cells. In the field of tumor immunotherapy, targeting T cell metabolism to enhance the immune response is a new therapeutic strategy for enhancing immunotherapy combined with traditional treatments.
Assuntos
Imunoterapia Adotiva/métodos , Neoplasias/imunologia , Neoplasias/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Animais , Antineoplásicos/imunologia , Antineoplásicos/metabolismo , Humanos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Neoplasias/terapiaRESUMO
The representative morphological features of pyroptosis are excessive cell swelling and subsequent membrane rupture. However, the mechanism underlying the cell's inherent inability to regulate volume during the progression of pyroptosis is poorly understood. In the current study, we found that both volume-activated chloride currents (Icl, vol) and the regulatory volume decrease (RVD) were markedly decreased in bone marrow-derived macrophages (BMDMs) undergoing pyroptosis induced by lipopolysaccharides (LPS) and nigericin. The inhibition of ICl, vol and RVD by the chloride channel blockers, tamoxifen or DCPIB, led to the emergence of pyroptosis-like phenotypes such as activated-caspase-1, pyroptotic-body-like bubbles, and a fried-egg-like appearance. Moreover, the expression of the volume-activated chloride channel (VRAC) constituent protein Leucine-Rich Repeat-Containing 8A (LRRC8A) was significantly down-regulated in pyroptotic BMDMs treated with LPS and nigericin. The silencing of LRRC8A expression by small interfering RNA (si)-LRRC8A transfection not only reduced ICl, vol and RVD, but also caused BMDMs to show pyroptosis-like manifestations such as activated-caspase-1, membrane bubbles, and have a fried-egg-like appearance. These results reveal a new mechanism for the loss of volume regulation in the process of pyroptotic cell swelling and strongly suggest that a functional deficiency of VRAC/LRRC8A plays a key role in this disorder.