RESUMO
Objective: Glomerular endothelium functions as a filtration barrier of metabolites in the kidney. Although X-ray irradiation modulated the permeability of the vascular endothelium, the response of human renal glomerular endothelial cells (HRGECs) to low-dose X-ray irradiation has not been investigated. We evaluated the impacts of low-dose X-ray irradiation on HRGECs and revealed the underlying mechanism. Methods: HRGECs were exposed to X-ray with doses of 0, 0.1, 0.5, 1.0, and 2.0 Gy. The proliferation, viability, and apoptosis of HRGECs were examined by MTT assay, trypan blue staining assay, and TUNEL staining, respectively. The paracellular permeability was assessed by paracellular permeability assay. The expression of VE-cadherin was investigated via immunofluorescence assay. Western blot and qRT-PCR detected the expression levels of VE-cadherin and CLDN5. Besides, the expression levels of pVE-cadherin (pY658), TGF-ß, TGF-ßRI, Src, p-Src, Smad2, p-Smad2, Smad3, p-Smad3, SNAIL, SLUG, and apoptosis-related proteins were tested by Western blot. Results: The proliferation, viability, and apoptosis of HRGECs were not affected by low-dose (<2.0 Gy) X-ray irradiation. X-ray irradiation dose-dependently reduced the level of VE-cadherin, and VE-cadherin and CLDN5 levels were reduced with X-ray irradiation. The levels of pY658, p-Src, p-Smad2, and p-Smad3 were upregulated with the increase in X-ray dose. Besides, the paracellular permeability of HRGECs was increased by even low-dose (<2.0 Gy) X-ray irradiation. Therefore, low-dose X-ray irradiation reduced the cumulative content of VE-cadherin and increased the level of pY658 via activation of the TGF-ß signaling pathway. Conclusion: Even though low-dose X-ray exposure had no impact on proliferation, viability, and apoptosis of HRGECs, it increased the paracellular permeability by deterioration and downregulation of VE-cadherin through stimulating the TGF-ß signaling pathway. This study built the framework for kidney response to low-dose irradiation exposure.
Assuntos
Células Endoteliais , Azul Tripano , Humanos , Células Endoteliais/metabolismo , Células Endoteliais/efeitos da radiação , Raios X , Azul Tripano/metabolismo , Caderinas/genética , Permeabilidade/efeitos da radiação , Rim , Fator de Crescimento Transformador beta/metabolismoRESUMO
Exosomes derived from mesenchymal stem cells (MSCs) are mostly responsible for the therapeutic effects of MSCs. To show the therapeutic effects of the human bone marrow MSC-derived exosomes (MSC-Exos) on colorectal cancer (CRC) and explore the molecular cross-talks between them, CRC cells were treated with the MSC-Exos. We found that MSC-Exos were enriched with miR-100 and miR-143, which effectively downregulated mTOR, Cyclin D1, K-RAS, HK2 while upregulated p-27 expression. All these effects were reversed by concurrent treatment with MSC-Exos and antagomiR-100, confirming that they were caused by exosomal transfer of miR-100 into recipient CRC cells. Moreover, exosomal miR-100 promoted endogenous miR-143 expression. The flow cytometry, MTT and trypan blue assays revealed that MSC-Exos could efficiently suppress proliferation and induce apoptosis of the CRC cells. Furthermore, wound healing, transwell migration and invasion assays confirmed their inhibitory effects on the migration and invasiveness of SW480 cells. We further confirmed these effects by analyzing the expression levels of epithelial to mesenchymal transition (EMT) factors and metastasis-related genes. Results showed that MSC-Exos significantly suppressed the expression of MMP2 and MMP9 (metastasis-related genes), SNAIL and TWIST (EMT-inducing transcription factors), Vimentin and N-cadherin (mesenchymal cell markers), whereas E-cadherin (epithelial cell marker) was remarkably up-regulated. Collectively, our data indicated that MSC-Exos could suppress proliferation, migration, invasion and metastasis while inducing the apoptosis of the CRC cells via miR-100/mTOR/miR-143 axis. Our findings highlight that MSC-Exo treatment as well as miR-100 restoration might be considered as potential therapeutic strategies for CRC.
Assuntos
Neoplasias Colorretais , Exossomos , MicroRNAs , Humanos , Exossomos/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Ciclina D1/metabolismo , Ciclina D1/farmacologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 2 da Matriz/farmacologia , Vimentina/metabolismo , Vimentina/farmacologia , Transição Epitelial-Mesenquimal , Antagomirs/metabolismo , Azul Tripano/metabolismo , Azul Tripano/farmacologia , MicroRNAs/genética , MicroRNAs/metabolismo , Proliferação de Células , Serina-Treonina Quinases TOR/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/terapia , Neoplasias Colorretais/metabolismo , Caderinas/metabolismo , Fatores de Transcrição/metabolismo , Movimento CelularRESUMO
The busulfan, an alkylating agent, suppresses endogenous spermatogenesis in recipient testes. However, considering a wide variation in the effects of busulfan among animal species, its dosage and route of infusion need optimization to prepare effective and safe recipients. Thus, the current study aimed to create a suitable recipient goat model for germ cell (Gc) transplantation through a single intra-testicular (i.t.) busulfan infusion under ultrasonographic (USG) guidance. As observed through the infusion of trypan blue under USG guidance into mediastinum testis (MT) of pre-pubertal Barbari bucks, 3-5 mL of trypan blue solution could fill almost 80% of seminiferous tubules. Thereafter, in Experiment-1, the effect of different busulfan doses (mg/kg) i.e. 0 [negative control, Group (Gr) 1; 0 mg/kg-MT], 1 (Gr 2; 1 mg/kg-MT), 2 (Gr 3; 2 mg/kg-MT), and 3 (Gr 4; 3 mg/kg-MT) were studied. Further, in Experiment-2, sterilizing effects of busulfan infusion through two different routes [MT or cavum vaginale (CV)] were compared. Following i.t. busulfan treatment, no adverse physiological effects or body weight loss were detected. The histological analyses demonstrate a dose-dependent depletion of Gc with almost complete loss of Gc and spermatogenic activities in Gr 3 and 4, and extensive fibrosis in Gr 4. A considerable suppression of spermatogenesis marked with devoid of endogenous spermatogonial population and absence of significant (P > 0.05) effect on key hematological variables were observed in 2 mg/kg-MT Gr. These findings coupled with the results of significant (P < 0.05) down-regulation of marker genes of undifferentiated spermatogonia (THY-1 and PLZF), Gc pluripotency (UCHL-1, OCT-4, and DDX-4), and adhesion (E-cadherin and ß-integrin); up-regulation of apoptotic genes (ID - 4 and BCL-6), and unchanged expression of Sertoli cell marker (vimentin), confirmed the safe and efficient depletion of endogenous Gc in 2 mg/kg-MT Gr. Furthermore, the effect of busulfan infusion on scrotal-testicular biometry, endocrine variables (plasma cortisol and testosterone), and Gc removal was more evident when busulfan was infused into MT than into CV. Overall, the results demonstrated that 2.0 mg/kg is an optimal single dose of busulfan when infused into the MT under USG guidance for the preparation of pre-pubertal recipient bucks. Overall, this study provides a basis to prepare suitable recipients through providing an available niche for efficient Gc transplantation in goats.
Assuntos
Bussulfano , Testículo , Animais , Bussulfano/farmacologia , Transplante de Células/veterinária , Cabras , Masculino , Espermatogênese , Espermatogônias , Azul Tripano/metabolismo , Azul Tripano/farmacologiaRESUMO
Purpose: Oxidative stress contributes to the pathogenesis of vision-impairing diseases. In the retina, retinal pigment epithelium (RPE) and Müller cells support neuronal homeostasis, but also contribute to pathological development under stressed conditions. Recent studies found that the investigational drug risuteganib (RSG) has a good safety profile, provided protection in experimental models, and improved visual acuity in patients. The present in vitro study evaluated the effects of RSG in RPE and Müller cell lines stressed with the oxidant hydrogen peroxide (H2O2). Methods: Human RPE (ARPE-19) and Müller (MIO-M1) cell lines were treated with various combinations of RSG and H2O2. Trypan blue assay was used to investigate the effect of compounds on cell viability. Gene expression was measured using RNA sequencing to identify regulated genes and the biological processes and pathways involved. Results: Trypan blue assay found RSG pre-treatment significantly protected against H2O2-induced cell death in ARPE-19 and MIO-M1 cells. Transcriptome analysis found H2O2 regulated genes in several disease-relevant biological processes, including cell adhesion, migration, death, and proliferation; ECM organization; angiogenesis; metabolism; and immune system processes. RSG pre-treatment modulated these gene expression profiles in the opposite direction of H2O2. Pathway analysis found genes in integrin, AP-1, and syndecan signaling pathways were regulated. Expression of selected RSG-regulated genes was validated using qRT-PCR. Conclusions: RSG protected cultured human RPE and Müller cell lines against H2O2-induced cell death and mitigated the associated transcriptome changes in biological processes and pathways relevant to the pathogenesis of retinal diseases. These results demonstrate RSG reduced oxidative stress-induced toxicity in two retinal cell lines with potential relevance to the treatment of human diseases.
Assuntos
Peróxido de Hidrogênio , Epitélio Pigmentado da Retina , Apoptose , Linhagem Celular , Sobrevivência Celular , Células Ependimogliais , Humanos , Peróxido de Hidrogênio/toxicidade , Estresse Oxidativo , Peptídeos , Transcriptoma , Azul Tripano/metabolismo , Azul Tripano/farmacologiaRESUMO
The prognosis of glioblastoma, which is the most frequent type of adultonset malignant brain tumor, is extremely poor. Therefore, novel therapeutic strategies are needed. Previous studies report that JCI20679, which is synthesized based on the structure of naturally occurring acetogenin, inhibits mitochondrial complex I and suppresses the growth of various types of cancer cells. However, the efficacy of JCI20679 on glioblastoma stem cells (GSCs) is unknown. The present study demonstrated that JCI20679 inhibited the growth of GSCs derived from a transposon systemmediated murine glioblastoma model more efficiently compared with the growth of differentiationinduced adherent cells, as determined by a trypan blue staining dye exclusion test. The inhibition of proliferation was accompanied by the blockade of cellcycle entry into the Sphase, as assessed by a BrdU incorporation assay. JCI20679 decreased the mitochondrial membrane potential, suppressed the oxygen consumption rate and increased mitochondrial reactive oxygen species generation, indicating that JCI20679 inhibited mitochondrial activity. The mitochondrial inhibition was revealed to increase phosphorylated (phospho)AMPKα levels and decrease nuclear factor of activated Tcells 2 (NFATc2) expression, and was accompanied by a decrease in calcineurin phosphatase activity. Depletion of phosphoAMPKα by knockdown of AMPKß recovered the JCI20679mediated decrease in NFATc2 expression levels, as determined by western blotting and reverse transcriptionquantitative PCR analysis. Overexpression of NFATc2 recovered the JCI20679mediated suppression of proliferation, as determined by a trypan blue staining dye exclusion test. These results suggest that JCI20679 inhibited mitochondrial oxidative phosphorylation, which activated AMPK and reduced NFATc2 expression levels. Moreover, systemic administration of JCI20679 extended the eventfree survival rate in a mouse model transplanted with GSCs. Overall, these results suggested that JCI20679 is a potential novel therapeutic agent against glioblastoma.
Assuntos
Glioblastoma , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Proliferação de Células , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Camundongos , Células-Tronco Neoplásicas/metabolismo , Azul Tripano/metabolismo , Azul Tripano/uso terapêuticoRESUMO
Abnormal deposition of α-synuclein aggregates in Lewy bodies and Lewy neurites is the hallmark lesion in Parkinson's disease (PD). These aggregates, thought to be the culprit of disease pathogenesis, spread throughout the brain as the disease progresses. Agents that inhibit α-synuclein aggregation and/or spread of aggregates would thus be candidate disease-modifying drugs. Here, we found that Chicago sky blue 6B (CSB) may be such a drug, showing that it inhibits α-synuclein aggregation and cell-to-cell propagation in both in vitro and in vivo models of synucleinopathy. CSB inhibited the fibrillation of α-synuclein in a concentration-dependent manner through direct binding to the N-terminus of α-synuclein. Furthermore, both seeded polymerization and cell-to-cell propagation of α-synuclein were inhibited by CSB treatment. Notably, CSB alleviated behavioral deficits and neuropathological features, such as phospho-α-synuclein and astrogliosis, in A53T α-synuclein transgenic mice. These results indicate that CSB directly binds α-synuclein and inhibits its aggregation, thereby blocking α-synuclein cell-to-cell propagation.
Assuntos
Doença de Parkinson , alfa-Sinucleína , Animais , Corpos de Lewy/patologia , Camundongos , Doença de Parkinson/patologia , Azul Tripano/metabolismo , alfa-Sinucleína/metabolismoRESUMO
Nutrient depletion in fed-batch cultures and at the end of batch cultures is among the main causes of stress on cells and a trigger of apoptosis. In this study, we investigated changes in the cytoplasm conductivity of Chinese hamster ovary (CHO) cells under controlled starvation. Employing a single-cell dielectrophoresis (DEP) cytometer, we measured the DEP response of CHO cells incubated in a medium without glucose and glutamine over a 48-h period. Using the measured data in conjunction with numerical simulations, we determined the cytoplasm conductivity of viable and apoptotic cell subpopulations. The results show that a small subpopulation of apoptotic cells emerges after 24 to 36â¯h of starvation and increases rapidly over a short period of time, <12â¯h. The apoptotic cells have a dramatically lower cytoplasm conductivity, â¼0.05â¯S/m, than viable cells, â¼0.45â¯S/m. Viability of starvation cultures was measured by fluorescent cytometry, DEP cytometry, and trypan blue exclusion assays. DEP, Annexin V, caspase-8, and 7-AAD assays show a similar decline in viability after 36â¯h of starvation and indicate a very low viability after 48â¯h. Trypan blue exclusion assay fails to detect early-stage viability decline and estimates a much higher viability after 48â¯h.
Assuntos
Apoptose , Meios de Cultura , Citoplasma/metabolismo , Eletroforese/métodos , Análise de Célula Única/métodos , Animais , Anexina A5/metabolismo , Células CHO , Caspase 8/metabolismo , Cricetulus , Dactinomicina/análogos & derivados , Dactinomicina/metabolismo , Citometria de Fluxo , Células HeLa , Humanos , Células Jurkat , Microfluídica , Azul Tripano/metabolismoRESUMO
OBJECTIVES: Endovascular techniques can now access the arterial blood supply of the pancreas in humans to enable therapeutics to reach the gland in high concentrations while concurrently avoiding issues related to non-targeted delivery. However, there is no way to replicate this in small animals. In a rat model, we therefore developed a novel non-terminal technique to deliver therapeutics to different regions of the pancreas, via its arterial blood supply. METHODS: In female Wistar rats, selective branches of the celiac artery were temporarily ligated, depending on the region of the pancreas being targeted. Trypan blue dye was then administered as a surrogate marker for a therapeutic agent, via the celiac artery, and its staining/distribution throughout the pancreas determined. Postoperatively, animals were monitored daily, and serum was evaluated for markers of pancreatitis, liver, and metabolic function. RESULTS: Using this technique, we could selectively target the head, body/tail, or entire gland of the pancreas, via its arterial blood supply, with minimal nontarget staining. Following the procedure, all animals recovered with no evidence of pancreatitis or liver/metabolic dysfunction. CONCLUSIONS: Our study demonstrates a novel technique that can be used to selectively deliver therapeutics directly to the rat pancreas in a safe manner with full recovery of the animal.
Assuntos
Artéria Celíaca/fisiopatologia , Artéria Celíaca/cirurgia , Sistemas de Liberação de Medicamentos/métodos , Pâncreas/irrigação sanguínea , Amilases/sangue , Animais , Biomarcadores/sangue , Velocidade do Fluxo Sanguíneo , Feminino , Humanos , Injeções Intra-Arteriais , Lipase/sangue , Pâncreas/metabolismo , Pancreatite/sangue , Pancreatite/diagnóstico , Ratos Wistar , Reprodutibilidade dos Testes , Azul Tripano/administração & dosagem , Azul Tripano/metabolismo , Azul Tripano/farmacocinéticaRESUMO
The possible emergence of praziquantel (PZQ)-tolerant and/or -resistant schistosomes requires the study and development of new antischistosomal drugs as alternatives to PZQ. The present study investigates the capability of 3 dyes-methylene blue (MB), neutral red (NR), and trypan blue (TB)-to assess the in vitro antischistosomal effect of antimalarial drugs on Schistosoma mansoni adult worms. S. mansoni adult worms were incubated in the medium alone as the control or in the medium supplemented with 10 µg/ml primaquine (PQ), artesunate (AR), or amodiaquine (AQ) for 5 days. Viabilities of the worms were observed following staining with MB, NR, or TB. The disparity of MB and NR staining among male and female adult worms treated with PQ, AR, and AQ correlated with the various levels of damage to the male and female worms. Furthermore, the severity of the damage to the adult worms treated with the 3 drugs appeared to be reflected in the TB staining status. The results indicate that the 3 non-fluorescent dyes can serve as useful complementary tools to assess the antischistosomal effect of antimalarial drugs.
Assuntos
Anti-Helmínticos/farmacologia , Antimaláricos/farmacologia , Testes de Sensibilidade Parasitária/métodos , Schistosoma mansoni/efeitos dos fármacos , Coloração e Rotulagem/métodos , Amodiaquina/farmacologia , Animais , Artesunato/farmacologia , Bioensaio/métodos , Feminino , Masculino , Azul de Metileno/metabolismo , Vermelho Neutro/metabolismo , Primaquina/farmacologia , Schistosoma mansoni/fisiologia , Análise de Sobrevida , Azul Tripano/metabolismoRESUMO
PURPOSE: To investigate the photochemical degradation of trypan blue (TB) and to identify decomposition products. METHODS: Defined solution samples of TB and a mixture with lutein/zeaxanthin were exposed to blue light. Thermal degradation processes were ruled out using controls not subjected to irradiation. All samples were analyzed using optical microscopy, UV/Vis spectroscopy, matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry and nuclear magnetic resonance (NMR) spectrometry. Degradation kinetics were determined based on changes in absorbance; intermediates were identified by analyzing mass differences of characteristic fragment ion peaks within the fragmentation patterns, and assignments were verified by NMR. RESULTS: TB demonstrated a photochemical degradation, which can be triggered by lutein/zeaxanthin. Intermediates vary depending on the presence of lutein/zeaxanthin. The self-sensitized photodegradation of TB occurs under generation of dimethyl sulfate and presumed formation of phenol. In contrast, within the presence of lutein/zeaxanthin the decomposition of TB indicates the formation of methoxyamine and sulfonyl arin. Thermal degradation processes were not observed. CONCLUSIONS: TB demonstrated a photodegradation that may be triggered by lutein/zeaxanthin and results in the formation of cytotoxic decomposition products. Our findings contribute to understand degradation mechanisms of TB and may elucidate previous clinical and experimental observations of cellular toxicity after TB application.
Assuntos
Luz , Luteína/metabolismo , Fotoquímica , Azul Tripano/metabolismo , Zeaxantinas/metabolismo , Cinética , Luteína/efeitos da radiação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Azul Tripano/efeitos da radiação , Zeaxantinas/efeitos da radiaçãoRESUMO
The role of Na+ in hypoxic injury was evaluated by a time-course analysis of damage in isolated livers perfused with N2-saturated buffer containing standard (143 mM) or low (25 mM) Na+ levels. Trypan blue uptake was used to detect non-viable cells. Under hypoxia with standard-Na+, trypan blue uptake began at the border between pericentral areas and periportal regions and increased in the latter zone; using a low-Na+ buffer, no trypan blue zonation occurred but a homogenous distribution of dye was found associated with sinusoidal endothelial cell (SEC) staining. A decrease in hyaluronic acid (HA) uptake, index of SEC damage, was observed using a low-Na+ buffer. A time dependent injury was confirmed by an increase in LDH and TBARS levels with standard-Na+ buffer. Using low-Na+ buffer, SEC susceptibility appears elevated under hypoxia and hepatocytes was protected, in an oxygen independent manner.
Assuntos
Hipóxia Celular/efeitos dos fármacos , Fígado/efeitos dos fármacos , Oxigênio , Sódio/farmacologia , Animais , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Fígado/metabolismo , Fígado/fisiopatologia , Masculino , Ratos , Coloração e Rotulagem , Fatores de Tempo , Azul Tripano/metabolismoRESUMO
Even with the advances of conventional treatment techniques, the nervous system cancer prognosis is still not favorable to the patient which makes alternative therapies needed to be studied. Photodynamic therapy (PDT) is presented as a promising therapy, which employs a photosensitive (PS) agent, light wavelength suitable for the PS agent, and molecular oxygen, producing reactive oxygen species in order to induce cell death. The aim of this study is to observe the PDT action in gliosarcoma cell using a chlorin (Photodithazine, PDZ). The experiments were done with 9L/lacZ lineage cells, grown in a DMEM medium supplemented with 10% fetal bovine serum and 1% penicillin/streptomycin solution and put in a culture chamber at 37 °C with an atmosphere of 5% CO2. The PS agent used was the PDZ to an LED light source device (Biopdi/IRRAD-LED 660) in the 660-nm region. The location of the PS agent was analyzed by fluorescence microscopy, and cell viability was analyzed by MTT assay (mitochondrial activity), exclusion by trypan blue (cell viability), and morphological examination through an optical microscope (Leica MD 2500). In the analysis of the experiments with PDZ, there was 100% cell death at different concentrations and clear morphological differences in groups with and without treatment. Furthermore, it was observed that the photodithazine has been focused on all nuclear and cytoplasmic extension; however, it cannot be said for sure whether the location is in the inside core region or on the plasma membrane. In general, the PDZ showed a promising photosensitive agent in PDT for the use of gliosarcoma.
Assuntos
Gliossarcoma/patologia , Glucosamina/análogos & derivados , Fotoquimioterapia/métodos , Morte Celular/efeitos dos fármacos , Morte Celular/efeitos da radiação , Linhagem Celular Tumoral , Forma Celular/efeitos dos fármacos , Forma Celular/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Glucosamina/farmacologia , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos da radiação , Fármacos Fotossensibilizantes/farmacologia , Azul Tripano/metabolismoRESUMO
The ubiquitin pathway plays a critical role in regulating diverse biological processes, and its dysregulation is associated with various diseases. Therefore, it is important to have a tool that can control the ubiquitin pathway in order to improve understanding of this pathway and to develop therapeutics against relevant diseases. We found that Chicago Sky Blue 6B binds directly to the ß-groove, a major interacting surface of ubiquitin. Hence, it could successfully inhibit the enzymatic activity of ubiquitin processing enzymes and the binding of ubiquitin to the CXCR4, a cell surface ubiquitin receptor. Furthermore, we demonstrated that this ubiquitin binding chemical could effectively suppress the ubiquitin induced cancer cell migration by blocking ubiquitin-CXCR4 interaction. Current results suggest that ubiquitin binding molecules can be developed as inhibitors of ubiquitin-protein interactions, which will have the value not only in unveiling the biological role of ubiquitin but also in treating related diseases.
Assuntos
Receptores CXCR4/metabolismo , Transdução de Sinais , Azul Tripano/metabolismo , Ubiquitina/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Células HEK293 , Humanos , Microscopia Confocal , Modelos Moleculares , Estrutura Molecular , Ligação Proteica/efeitos dos fármacos , Domínios Proteicos , Receptores CXCR4/química , Azul Tripano/química , Azul Tripano/farmacologia , Ubiquitina/químicaRESUMO
Trypan blue is a colorimetric dye that stains dead cells with a blue color easily observed using light microscopy at low resolution. The staining procedure is rapid and cells can be analyzed within minutes. The number of live (unstained) and dead (blue) cells can be counted using a hemocytometer on a basic upright microscope. Trypan blue staining is therefore a convenient assay for rapidly determining the overall viability of cells in a culture before commencing scientific experimentation, or for quantitating cell death following treatment with any cytotoxic stimuli.
Assuntos
Morte Celular , Corantes/metabolismo , Microscopia/métodos , Coloração e Rotulagem/métodos , Azul Tripano/metabolismo , Animais , Contagem de Células/métodos , HumanosRESUMO
Cryopreserved peripheral blood mononuclear cells (PBMCs) are widely used in studies of dengue. In this disease, elevated frequency of apoptotic PBMCs has been described, and molecules such as soluble tumor necrosis factor (TNF)-related apoptosis-inducing ligands (sTRAIL) are involved. This effect of dengue may affect the efficiency of PBMC cryopreservation. Here, we evaluate the viability (trypan blue dye exclusion and amine-reactive dye staining) and functionality (frequency of gamma interferon [IFN-γ]-producing T cells after polyclonal stimulation) of fresh and cryopreserved PBMCs from children with dengue (in acute and convalescence phases), children with other febrile illnesses, and healthy children as controls. Plasma sTRAIL levels were also evaluated. The frequencies of nonviable PBMCs detected by the two viability assays were positively correlated (r = 0.74; P < 0.0001). Cryopreservation particularly affected the PBMCs of children with dengue, who had a higher frequency of nonviable cells than healthy children and children with other febrile illnesses (P ≤ 0.02), and PBMC viability levels were restored in the convalescent phase. In the acute phase, an increased frequency of CD3+ CD8+ amine-positive cells was found before cryopreservation (P = 0.01). Except for B cells in the acute phase, cryopreservation usually did not affect the relative frequencies of viable PBMC subpopulations. Dengue infection reduced the frequency of IFN-γ-producing CD3+ cells after stimulation compared with healthy controls and convalescent-phase patients (P ≤ 0.003), and plasma sTRAIL correlated with this decreased frequency in dengue (rho = -0.56; P = 0.01). Natural dengue infection in children can affect the viability and functionality of cryopreserved PBMCs.
Assuntos
Criopreservação , Dengue/imunologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Linfócitos T/imunologia , Adolescente , Sobrevivência Celular , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Interferon gama/biossíntese , Leucócitos Mononucleares/patologia , Masculino , Dengue Grave/imunologia , Azul Tripano/metabolismoRESUMO
Cytotoxicity assays are used for drug screening and cytotoxicity tests of chemicals. Nowadays, various reagents are used for cell viability detection. They are based on various cell functions such as enzyme activity, cell membrane permeability, cell adherence, ATP production, co-enzyme production and nucleotide uptake activity. Many have established methods such as colony formation method, crystal violet method, tritium-labelled thymidine uptake method, MTT and WST methods, which are used for counting the number of live cells. Moreover, trypan blue is a widely used assay for staining dead cells. In this method, cell viability must be determined by counting the unstained cells with a microscope or other instruments. This chapter is a collection of all these methods to be followed by researchers in a sequential manner.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Bioprospecção/métodos , Descoberta de Drogas/métodos , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Neoplasias/tratamento farmacológico , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Colorimetria , Corantes/metabolismo , Humanos , Microscopia , Neoplasias/metabolismo , Neoplasias/patologia , Compostos Fitoquímicos/isolamento & purificação , Fitoterapia , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Sais de Tetrazólio/metabolismo , Tiazóis/metabolismo , Azul Tripano/metabolismoRESUMO
BACKGROUND: Pancreatic cancer is a highly lethal cancer due to early metastasis and resistance to current chemotherapeutic agents. Abnormal protein kinase B (AKT) activation is an important mechanism of chemoresistance to gemcitabine, the most widely used agent in pancreatic cancer. MATERIAL AND METHODS: In the study, we tested the hypothesis that combining an AKT inhibitor with gemcitabine would augment anti-tumor activity. We treated human pancreatic cancer MiaPaCa-2 cells with gemcitabine and the AKT inhibitor triciribine, alone and in combination, and evaluated treatment effects using trypan blue assay, 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium (MTT) assay, and cell death enzyme-linked immunosorbant assay. Colorimetric data of MTT assay were computationally analyzed for synergism of the combination therapy by CalcuSyn2 (Biosoft, Great Shelford, Cambridge, UK). RESULTS: Both gemcitabine and triciribine inhibited cell growth in a dose-dependent manner. Triciribine synergistically enhanced the cytotoxic activity of gemcitabine. The combination index (CI) provides the synergistic, additive, or antagonistic effects of the two-drug combination. CI at the 50% effective dose at 1:500 ratio of gemcitabine to triciribine was 0.74, indicating the synergistic effect of the drugs. The combination treatment with the non-apoptotic dose of each agent distinctly induced apoptosis, with gemcitabine in combination with triciribine, synergistically inhibiting pancreatic cancer cell growth and inducing apoptosis. CONCLUSION: These findings support the use of triciribine to overcome activated AKT-mediated resistance of pancreatic cancer to gemcitabine.
Assuntos
Acenaftenos/uso terapêutico , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Ribonucleotídeos/uso terapêutico , Acenaftenos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Humanos , Neoplasias Pancreáticas/enzimologia , Neoplasias Pancreáticas/patologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ribonucleotídeos/farmacologia , Coloração e Rotulagem , Azul Tripano/metabolismo , GencitabinaRESUMO
Neuroinvasive larvae of the common dog and cat roundworms, Toxocara canis and Toxocara cati, may cause severe neurological and neuropsychological disturbances in humans. Despite their pathogenic potential and high prevalence worldwide, little is known about their cell-specific influences and cerebral host-pathogen interactions in neurotoxocarosis. To address this discrepancy, a co-culture system of viable larvae with murine neuronal (CAD), oligodendrocytal (BO-1) and microglial (BV-2) cell lines has been established. Additionally, murine adult brain slices have been co-cultured with Toxocara larvae to consider complex organotypic cell-cell interplay. Cytotoxicity of larval presence was measured enzymatically and microscopically. Microscopic evaluation using trypan blue exclusion assay revealed to be less reliable and sensitive than the lactate dehydrogenase activity assay. Ultimately, even low numbers of both T. canis and T. cati larvae have impaired survival of differentiated CAD cells, which morphologically resemble primary neurons. In contrast, viability of oligodendrocytal and microglial cells as well as brain slices was not impaired by larval presence. Therefore, immune-mediated mechanisms or trauma by migrating larvae presumably induce the in vivo pathology rather than acute cytotoxic effects. Conclusively, the helminthic larvae co-culture system presented here is a valuable in vitro tool to study cell-specific effects of parasitic larvae and their products.
Assuntos
Interações Hospedeiro-Patógeno/fisiologia , Toxocara/fisiologia , Toxocaríase/patologia , Animais , Encéfalo/citologia , Encéfalo/parasitologia , Linhagem Celular , Sobrevivência Celular , Técnicas de Cocultura , Técnicas In Vitro , L-Lactato Desidrogenase/metabolismo , Larva , Camundongos , Toxocaríase/parasitologia , Azul Tripano/metabolismoRESUMO
Environmental release of benzidine-based dyes is a matter of health concern. Here, a microbial consortium was enriched from textile dye contaminated soils and investigated for biodegradation of the carcinogenic benzidine-based dye Trypan Blue using wheat bran (WB) as growth medium. The PCR-DGGE analysis of enriched microbial consortium revealed the presence of 15 different bacteria. Decolorization studies suggested that the microbial consortium has high metabolic activity towards Trypan Blue as complete removal of 50 mgâL-1 dye was observed within 24 h at 30 ± 0.2 °C and pH 7. Significant reduction in TOC (64%) and COD (88%) of dye decolorized broths confirmed mineralization. Induction in azoreductase (500%), NADH-DCIP reductase (264%) and laccase (275%) proved enzymatic decolorization of dye. HPLC analysis of dye decolorized products showed the formation of six metabolites while the FTIR spectrum indicated removal of diazo bonds at 1612.30 and 1581.34 cm-1. The proposed dye degradation pathway based on GC-MS and enzyme analysis suggested the formation of two low molecular weight intermediates. Phytotoxicity and acute toxicity studies revealed the less toxic nature of the dye degradation products. These results provide experimental evidence for the utilization of agricultural waste as a novel low-cost growth medium for biodegradation of benzidine-based dyes, and suggested the potential of the microbial consortium in detoxification.
Assuntos
Carcinógenos/metabolismo , Corantes/metabolismo , Fibras na Dieta/microbiologia , Recuperação e Remediação Ambiental/métodos , Consórcios Microbianos , Azul Tripano/metabolismo , Biodegradação Ambiental , Carcinógenos/toxicidade , Cromatografia Líquida de Alta Pressão , Corantes/toxicidade , Cromatografia Gasosa-Espectrometria de Massas , Azul Tripano/toxicidadeRESUMO
The diagnostic value of modified Chicago sky blue (CSB) stain and potassium hydroxide (KOH) mount for superficial mycoses was compared using fungal culture as gold standard. The sensitivity and screening time of the CSB stain were superior to the KOH mount. The CBS stain is simple, quick and reliable for diagnosing superficial mycoses.