ABSTRACT
Cutaneous melanoma (CM) is an extremely aggressive cancer presenting low survival and high mortality. The vast majority of patients affected by this disease does not respond or show resistance to the chemotherapeutic drugs, which makes the treatment ineffective. In this sense, the necessity for the development of new agents to assist in CM therapy is extremely important. One of the sources of great interest in this search are compounds of natural origin. Among these compounds, caffeic acid has demonstrated a broad spectrum of pharmacological activities as well as antitumor effects in some types of cancer. Therefore, the objective of this work was to investigate the possible antitumor effect of caffeic acid on the SK-Mel-28 cell line, human CM cells. Cells were cultured in flasks with culture medium containing fetal bovine serum, antibiotic, and antifungal, and maintained in ideal conditions. Cells were treated with 25 µM, 50 µM, 100 µM, 150 µM and 200 µM of caffeic acid and dacarbazine at 1 mg/mL. We verified the effect on cell viability and cell death, apoptosis, cell cycle, colony formation and gene expression of caspases. Results showed a decrease in cell viability, cell death induction by apoptosis, inhibition of colony formation, modulation of cell cycle and alterations in gene expression of caspases after caffeic acid treatment. These results suggest an antitumor effect of the compound on SK-Mel-28 cells. This study provides original information on mechanisms by which caffeic acid may play a key role in preventing tumor progression in human melanoma cells.
Subject(s)
Caffeic Acids/pharmacology , Melanoma/drug therapy , Adult , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Caffeic Acids/metabolism , Caspases/drug effects , Caspases/genetics , Cell Cycle/drug effects , Cell Cycle Proteins/drug effects , Cell Cycle Proteins/genetics , Cell Division/drug effects , Cell Line, Tumor/drug effects , Cell Proliferation/drug effects , Cell Survival/drug effects , Dacarbazine/pharmacology , Female , Healthy Volunteers , Humans , Male , Melanoma/pathology , Skin Neoplasms/drug therapy , Skin Neoplasms/metabolism , Skin Neoplasms/pathology , Melanoma, Cutaneous MalignantABSTRACT
BACKGROUND/AIMS: Parthenolide is a sesquiterpene lactone that is present in plants of the Tanacetum genus, for which many biological effects have already been reported, including antiherpetic activity. Although the effectiveness of parthenolide against Herpes simplex virus 1 (HSV-1) has already been demonstrated, such findings are still controversial. The objective of this study was to investigate the ways in which parthenolide exerts anti-HSV-1 activity. METHODS: The cytotoxicity and antiviral activity of parthenolide were determined by the MTT method and plaque reduction assay, respectively. The expression of cell and viral proteins during the treatment of infected cells was investigated by Western blot. RESULTS: Both strains of HSV-1 were sensitive to parthenolide, and parthenolide was active only after penetration of the virus into the host cell. The expression of p65 protein decreased, the expression of caspases 8 and 9 increased, and the expression of c-Jun N-terminal kinase (JNK) and p38 protein was altered in infected cells after parthenolide treatment, resulting in lower cell survival. The low expression of viral proteins gB, gD, and ICP0 confirmed the reduction of HSV-1 particle production. CONCLUSION: Parthenolide exerts anti-HSV-1 activity by impairing cell viability, which consequently interferes with the efficient infection and production of new viral particles.
Subject(s)
Antiviral Agents/pharmacology , Herpes Simplex/drug therapy , Herpesvirus 1, Human/drug effects , Sesquiterpenes/pharmacology , Tanacetum/chemistry , Animals , Caspases/drug effects , Caspases/metabolism , Cell Survival/drug effects , Chlorocebus aethiops , Herpes Simplex/virology , Herpesvirus 1, Human/physiology , Humans , NF-kappa B/drug effects , NF-kappa B/metabolism , Plant Components, Aerial/chemistry , Vero Cells , Viral Proteins/drug effects , Viral Proteins/metabolism , Virus Replication/drug effectsABSTRACT
BACKGROUND: Heavy metals can cause great harm to Siberian tigers in the natural environment. Cadmium (Cd2+) is an environmental contaminant that affects multiple cellular processes, including cell proliferation, differentiation, and survival. It has been shown to induce apoptosis in a variety of cell types and tissues. RESULTS: We investigated the apoptotic effects of Cd2+ on Siberian tiger fibroblasts in vitro. Our research revealed the typical signs of apoptosis after Cd2+ exposure. Apoptosis was dose- (0-4.8 µM) and duration-dependent (12-48 h), and proliferation was strongly inhibited. Cd2+ increased the activity of caspase-3, -8, and -9 and disrupted calcium homeostasis by causing oxidative stress and mitochondrial dysfunction. It also increased K+ efflux and altered the mRNA levels of Bax, Bcl-2, caspase-3, caspase-8, Fas, and p53. CONCLUSIONS: Our results suggest that Cd2+ triggers the apoptosis of Siberian tiger fibroblasts by disturbing intracellular homeostasis. These results will aid in our understanding of the effects of Cd2+ on Siberian tigers and in developing interventions to treat and prevent cadmium poisoning.
Subject(s)
Apoptosis/drug effects , Cadmium/toxicity , Fibroblasts/drug effects , Homeostasis/drug effects , Intracellular Space/drug effects , Tigers , Animals , Apoptosis/genetics , Caspases/analysis , Caspases/drug effects , Cell Cycle/drug effects , Cells, Cultured , Comet Assay/veterinary , DNA Damage , Fibroblasts/physiology , Homeostasis/physiology , Membrane Potential, Mitochondrial/drug effects , Microscopy, Electron, Transmission , Polymerase Chain Reaction , Reactive Oxygen Species/analysis , Reverse Transcription , SiberiaABSTRACT
BACKGROUND: Heavy metals can cause great harm to Siberian tigers in the natural environment. Cadmium (Cd2+) is an environmental contaminant that affects multiple cellular processes, including cell proliferation, differentiation, and survival. It has been shown to induce apoptosis in a variety of cell types and tissues. RESULTS: We investigated the apoptotic effects of Cd2+ on Siberian tiger fibroblasts in vitro. Our research revealed the typical signs of apoptosis after Cd²+ exposure. Apoptosis was dose- (0-4.8 µM) and duration-dependent (12-48 h), and proliferation was strongly inhibited. Cd²+ increased the activity of caspase-3, -8, and -9 and disrupted calcium homeostasis by causing oxidative stress and mitochondrial dysfunction. It also increased K+ efflux and altered the mRNA levels of Bax, Bcl-2, caspase-3, caspase-8, Fas, and p53. CONCLUSIONS: Our results suggest that Cd2+ triggers the apoptosis of Siberian tiger fibroblasts by disturbing intracellular homeostasis. These results will aid in our understanding of the effects of Cd2+ on Siberian tigers and in developing interventions to treat and prevent cadmium poisoning.
Subject(s)
Animals , Cadmium/toxicity , Apoptosis/drug effects , Intracellular Space/drug effects , Tigers , Fibroblasts/drug effects , Homeostasis/drug effects , Siberia , DNA Damage , Cell Cycle/drug effects , Cells, Cultured , Polymerase Chain Reaction , Reactive Oxygen Species/analysis , Apoptosis/genetics , Caspases/analysis , Caspases/drug effects , Comet Assay/veterinary , Microscopy, Electron, Transmission , Reverse Transcription , Membrane Potential, Mitochondrial/drug effects , Fibroblasts/physiology , Homeostasis/physiologyABSTRACT
BACKGROUND: Doxycycline (DC) has been shown to possess non-antibiotic properties including Fas/Fas Ligand (FasL)-mediated apoptosis against several tumor types in the concentration range of 10-40 µg/mL. However, the effect of DC in apoptotic signaling at much low concentrations was not studied. METHODS: The present study investigated the attenuation effect of low dose of DC on FasL-induced apoptosis in HeLa cell by the methods of MTT assay, fluorescence microscopy, DNA fragmentation, flow cytometry analysis, and western blotting. RESULTS AND CONCLUSION: In the present findings we showed that low concentration of DC (<2.0 µg/mL) exhibited protective effects against FasL-induced apoptosis in HeLa cells. FasL treatment to HeLa cells resulted in a concentration-dependent induction of cell death, and treatment with low concentrations of DC (0.1-2 µg/mL) significantly (p < 0.001) attenuated the FasL-induced cell death as measured by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Further, the FasL-induced apoptotic features in HeLa cells, such as morphological changes, DNA fragmentation and cell cycle arrest was also inhibited by DC (0.5 µg/mL). Tetracycline and minocycline also showed similar anti-apoptotic effects but were not significant when compared to DC, tested at same concentrations. Further, DC (0.01-16 µg/mL) did not influence the hydrogen peroxide- or cisplatin-induced intrinsic apoptotic pathway in HeLa cells. Protein analysis using Western blotting confirmed that FasL-induced cleavage/activation of caspase-8 and caspase-3, were inhibited by DC treatment at low concentration (0.5 µg/mL). Considering the overall data, we report for the first time that DC exhibited anti-apoptotic effects at low concentrations in HeLa cells by inhibition of caspase activation via FasL-induced extrinsic pathway.
Subject(s)
Apoptosis/drug effects , Caspases/drug effects , Doxycycline/administration & dosage , Fas Ligand Protein/drug effects , Animals , Blotting, Western , Dose-Response Relationship, Drug , Doxycycline/pharmacology , Enzyme Activation , Flow Cytometry , HeLa Cells , Humans , Mice , NIH 3T3 CellsABSTRACT
El Consejo Federal de Medicina de Brasil (CFM) -órgano normativo y fiscalizador del ejercicio ético de la medicina- prohibió, en 2008, la participación de médicos brasileños en investigaciones que utilizaran placebo para enfermedades con tratamiento eficaz y efectivo, en contraposición a la Declaración de Helsinki, que permite su uso en condiciones metodológicamente justificadas. Con el objetivo de verificar si la normativa ética del CFM modificó el uso de placebo en ensayos clínicos de fase III en Brasil, se analizaron varias características de sus registros en el ClinicalTrials.gov, en los períodos de 2003 a 2007 y de 2009 a 2013. Se concluye que: a) la normativa promulgada por el CFM en 2008 fue ineficaz y prevaleció la posición adoptada por la Declaración de Helsinki; b) el patrocinio de ensayos con placebo por parte de la industria farmacéutica multinacional fue significativo; c) predominaron las investigaciones de fármacos para enfermedades crónicas, y fueron poco significativas para las enfermedades postergadas, de importancia para Brasil.(AU)
In 2008, Brazils Federal Council of Medicine [Conselho Federal de Medicina] (CFM) - regulatory and supervisory agency on the ethical practice of medicine - banned the participation of Brazilian doctors in studies using placebos for diseases with efficient and effective treatment. This position differs with the Helsinki Declaration, which allows the use of placebos in methodologically justified conditions. To ascertain whether the CMFs ethical regulation modified the use of placebos in phase III clinical trials in Brazil, characteristics of the records in ClinicalTrials.gov were researched in the periods from 2003 to 2007 and from 2009 to 2013. The conclusions reached were: a) the regulations issued by the CFM in 2008 were ineffective and the position adopted by the Helsinki Declaration prevails; b) there was significant sponsorship by the multinational pharmaceutical industry of trials with placebos; c) the research was predominantly on new drugs for chronic diseases, with little study done of the neglected diseases which are of great importance to Brazil.(AU)
Subject(s)
Animals , Rats , Apoptosis/genetics , Gene Expression Regulation, Enzymologic/genetics , Heme/deficiency , Nerve Degeneration/genetics , Neurons/metabolism , Porphyrias/complications , Apoptosis/drug effects , Caspases/drug effects , Caspases/metabolism , Cell Survival/drug effects , Cell Survival/genetics , Collagen Type XI/drug effects , Collagen Type XI/metabolism , Cyclic AMP Response Element-Binding Protein/drug effects , Cyclic AMP Response Element-Binding Protein/genetics , Cyclic AMP Response Element-Binding Protein/metabolism , Down-Regulation/drug effects , Down-Regulation/physiology , Enzyme Inhibitors , Gene Expression Regulation, Enzymologic/drug effects , Heme/biosynthesis , Heptanoates , MAP Kinase Signaling System/drug effects , MAP Kinase Signaling System/physiology , Membrane Proteins/drug effects , Membrane Proteins/genetics , Membrane Proteins/metabolism , Nerve Degeneration/metabolism , Nerve Degeneration/physiopathology , Nerve Tissue Proteins/drug effects , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Neural Cell Adhesion Molecules/drug effects , Neural Cell Adhesion Molecules/genetics , Neural Cell Adhesion Molecules/metabolism , Neurons/drug effects , Neurons/pathology , PC12 Cells , Poly(ADP-ribose) Polymerases , Porphyrias/metabolism , Porphyrias/physiopathology , RNA, Messenger/drug effects , RNA, Messenger/metabolism , RNA-Binding Proteins/drug effects , RNA-Binding Proteins/genetics , RNA-Binding Proteins/metabolism , SMN Complex Proteins , Up-Regulation/drug effects , Up-Regulation/physiology , Vesicular Transport Proteins/drug effects , Vesicular Transport Proteins/genetics , Vesicular Transport Proteins/metabolismABSTRACT
El Consejo Federal de Medicina de Brasil (CFM) -órgano normativo y fiscalizador del ejercicio ético de la medicina- prohibió, en 2008, la participación de médicos brasileños en investigaciones que utilizaran placebo para enfermedades con tratamiento eficaz y efectivo, en contraposición a la Declaración de Helsinki, que permite su uso en condiciones metodológicamente justificadas. Con el objetivo de verificar si la normativa ética del CFM modificó el uso de placebo en ensayos clínicos de fase III en Brasil, se analizaron varias características de sus registros en el ClinicalTrials.gov, en los períodos de 2003 a 2007 y de 2009 a 2013. Se concluye que: a) la normativa promulgada por el CFM en 2008 fue ineficaz y prevaleció la posición adoptada por la Declaración de Helsinki; b) el patrocinio de ensayos con placebo por parte de la industria farmacéutica multinacional fue significativo; c) predominaron las investigaciones de fármacos para enfermedades crónicas, y fueron poco significativas para las enfermedades postergadas, de importancia para Brasil.
In 2008, Brazil's Federal Council of Medicine [Conselho Federal de Medicina] (CFM) - regulatory and supervisory agency on the ethical practice of medicine - banned the participation of Brazilian doctors in studies using placebos for diseases with efficient and effective treatment. This position differs with the Helsinki Declaration, which allows the use of placebos in methodologically justified conditions. To ascertain whether the CMF's ethical regulation modified the use of placebos in phase III clinical trials in Brazil, characteristics of the records in ClinicalTrials.gov were researched in the periods from 2003 to 2007 and from 2009 to 2013. The conclusions reached were: a) the regulations issued by the CFM in 2008 were ineffective and the position adopted by the Helsinki Declaration prevails; b) there was significant sponsorship by the multinational pharmaceutical industry of trials with placebos; c) the research was predominantly on new drugs for chronic diseases, with little study done of the neglected diseases which are of great importance to Brazil.
Subject(s)
Animals , Rats , Apoptosis/genetics , Gene Expression Regulation, Enzymologic/genetics , Heme/deficiency , Nerve Degeneration/genetics , Neurons/metabolism , Porphyrias/complications , Apoptosis/drug effects , Caspases/drug effects , Caspases/metabolism , Cell Survival/drug effects , Cell Survival/genetics , Collagen Type XI/drug effects , Collagen Type XI/metabolism , Cyclic AMP Response Element-Binding Protein/drug effects , Cyclic AMP Response Element-Binding Protein/genetics , Cyclic AMP Response Element-Binding Protein/metabolism , Down-Regulation/drug effects , Down-Regulation/physiology , Enzyme Inhibitors , Gene Expression Regulation, Enzymologic/drug effects , Heme/biosynthesis , Heptanoates , MAP Kinase Signaling System/drug effects , MAP Kinase Signaling System/physiology , Membrane Proteins/drug effects , Membrane Proteins/genetics , Membrane Proteins/metabolism , Nerve Degeneration/metabolism , Nerve Degeneration/physiopathology , Nerve Tissue Proteins/drug effects , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Neural Cell Adhesion Molecules/drug effects , Neural Cell Adhesion Molecules/genetics , Neural Cell Adhesion Molecules/metabolism , Neurons/drug effects , Neurons/pathology , Poly(ADP-ribose) Polymerases , Porphyrias/metabolism , Porphyrias/physiopathology , RNA, Messenger/drug effects , RNA, Messenger/metabolism , RNA-Binding Proteins/drug effects , RNA-Binding Proteins/genetics , RNA-Binding Proteins/metabolism , SMN Complex Proteins , Up-Regulation/drug effects , Up-Regulation/physiology , Vesicular Transport Proteins/drug effects , Vesicular Transport Proteins/genetics , Vesicular Transport Proteins/metabolismABSTRACT
BACKGROUND: Doxycycline (DC) has been shown to possess non-antibiotic properties including Fas/Fas Ligand (FasL)-mediated apoptosis against several tumor types in the concentration range of 10-40 µg/mL. However, the effect of DC in apoptotic signaling at much low concentrations was not studied. METHODS: The present study investigated the attenuation effect of low dose of DC on FasL-induced apoptosis in HeLa cell by the methods of MTT assay, fluorescence microscopy, DNA fragmentation, flow cytometry analysis, and western blotting. RESULTS AND CONCLUSION: In the present findings we showed that low concentration of DC (<2.0 µg/mL) exhibited protective effects against FasL-induced apoptosis in HeLa cells. FasL treatment to HeLa cells resulted in a concentration-dependent induction of cell death, and treatment with low concentrations of DC (0.1-2 µg/mL) significantly (p < 0.001) attenuated the FasL-induced cell death as measured by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazo-lium bromide (MTT) assay. Further, the FasL-induced apoptotic features in HeLa cells, such as morphological changes, DNA fragmentation and cell cycle arrest was also inhibited by DC (0.5 µg/mL). Tetracycline and minocycline also showed similar anti-apoptotic effects but were not significant when compared to DC, tested at same concentrations. Further, DC (0.01-16 µg/mL) did not influence the hydrogen peroxide- or cisplatin-induced intrinsic apoptotic pathway in HeLa cells. Protein analysis using Western blotting confirmed that FasL-induced cleavage/activation of cas-pase-8 and caspase-3, were inhibited by DC treatment at low concentration (0.5 µg/mL). Considering the overall data, we report for the first time that DC exhibited anti-apoptotic effects at low concentrations in HeLa cells by inhibition of caspase activation via FasL-induced extrinsic pathway.
Subject(s)
Humans , Animals , Mice , Apoptosis/drug effects , Doxycycline/administration & dosage , Caspases/drug effects , Fas Ligand Protein/drug effects , HeLa Cells , Blotting, Western , Doxycycline/pharmacology , NIH 3T3 Cells , Dose-Response Relationship, Drug , Enzyme Activation , Flow CytometryABSTRACT
INTRODUCTION: Cardiac arrest during heart surgery is a common procedure and allows the surgeon to perform surgical procedures in an environment free of blood and movement. Using a model of isolated rat heart, the authors compare a new cardioplegic solution containing histidine-tryptophan-glutamate (group 2) with the histidine-tryptophan-alphacetoglutarate (group 1) routinely used by some cardiac surgeons. OBJECTIVE: To assess caspase, IL-8 and KI-67 in isolated rat hearts using immunohistochemistry. METHODS: 20 Wistar male rats were anesthetized and heparinized. The chest was opened, cardioctomy was performed and 40 ml/kg of the appropriate cardioplegic solution was infused. The hearts were kept for 2 hours at 4ºC in the same solution, and thereafter, placed in the Langendorff apparatus for 30 minutes with Ringer-Locke solution. Immunohistochemistry analysis of caspase, IL-8, and KI-67 were performed. RESULTS: The concentration of caspase was lower in group 2 and Ki-67 was higher in group 2, both P<0.05. There was no statistical difference between the values of IL-8 between the groups. CONCLUSION: Histidine-tryptophan-glutamate solution was better than histidine-tryptophan-alphacetoglutarate solution because it reduced caspase (apoptosis), increased KI-67 (cell proliferation), and showed no difference in IL-8 levels compared to group 1. This suggests that the histidine-tryptophan-glutamate solution was more efficient than the histidine-tryptophan-alphacetoglutarate for the preservation of hearts of rat cardiomyocytes.
Subject(s)
Cardioplegic Solutions/pharmacology , Glutamic Acid/pharmacology , Glutarates/pharmacology , Heart/drug effects , Histidine/pharmacology , Tryptophan/pharmacology , Animals , Apoptosis/drug effects , Cardioplegic Solutions/chemistry , Caspases/analysis , Caspases/drug effects , Immunohistochemistry , Interleukin-8/analysis , Interleukin-8/drug effects , Ki-67 Antigen/analysis , Ki-67 Antigen/drug effects , Male , Myocytes, Cardiac , Rats, Wistar , Reproducibility of Results , Time FactorsABSTRACT
Introdução: A parada do coração durante a cirurgia cardíaca é procedimento comum e permite que o cirurgião realize os procedimentos cirúrgicos em ambiente isento de sangue e movimento. Os autores comparam, em modelo de coração isolado de rato, uma nova solução cardioplégica com histidina-triptofano-glutamato (grupo 2) com a histidina-triptofano-alfacetoglutarato (grupo 1) já utilizada de rotina por alguns cirurgiões cardíacos. Objetivo: Avaliar por análise imuno-histoquímica a caspase, a IL-8 e KI-67 em corações isolados de ratos. Métodos: 20 ratos machos de raça Wistar foram anestesiados e heparinizados. O tórax foi aberto, realizado cardiectomia e infundido 40 ml/kg de solução cardioplégica apropriada. Os corações foram mantidos por 2 horas na mesma solução a 4ºC e, após esse período, colocados em aparato de Langendorff por 30 minutos com solução de Ringer Locke. Foram feitas análises imuno-histoquímicas para caspase, IL-8 e KI-67. Resultados: A concentração de caspase estava menor no grupo 2 e da KI-67 estava mais elevada no grupo 2, ambos com P<0,05. Não houve diferença estatística entre os valores de IL-8 entre os grupos. Conclusão: A solução com histidina-triptofano-glutamato foi melhor que a com histidina-triptofano-cetoglutarato, pois reduziu a caspase (apoptose), aumentou o KI-67 (proliferação celular) e não apresentou valores diferentes de IL-8 (inflamação e necrose) que no grupo 1. Isso sugere que a solução histidina-triptofano-glutamato foi mais eficiente que a histidina-triptofano-cetoglutarato na preservação dos cardiomiócitos dos corações de ratos. .
Introduction: Cardiac arrest during heart surgery is a common procedure and allows the surgeon to perform surgical procedures in an environment free of blood and movement. Using a model of isolated rat heart, the authors compare a new cardioplegic solution containing histidine-tryptophan-glutamate (group 2) with the histidine-tryptophan-alphacetoglutarate (group 1) routinely used by some cardiac surgeons. Objective: To assess caspase, IL-8 and KI-67 in isolated rat hearts using immunohistochemistry. Methods: 20 Wistar male rats were anesthetized and heparinized. The chest was opened, cardioctomy was performed and 40 ml/kg of the appropriate cardioplegic solution was infused. The hearts were kept for 2 hours at 4ºC in the same solution, and thereafter, placed in the Langendorff apparatus for 30 minutes with Ringer-Locke solution. Immunohistochemistry analysis of caspase, IL-8, and KI-67 were performed. Results: The concentration of caspase was lower in group 2 and Ki-67 was higher in group 2, both P<0.05. There was no statistical difference between the values of IL-8 between the groups. Conclusion: Histidine-tryptophan-glutamate solution was better than histidine-tryptophan-alphacetoglutarate solution because it reduced caspase (apoptosis), increased KI-67 (cell proliferation), and showed no difference in IL-8 levels compared to group 1. This suggests that the histidine-tryptophan-glutamate solution was more efficient than the histidine-tryptophan-alphacetoglutarate for the preservation of hearts of rat cardiomyocytes. .
Subject(s)
Animals , Male , Cardioplegic Solutions/pharmacology , Glutamic Acid/pharmacology , Glutarates/pharmacology , Heart/drug effects , Histidine/pharmacology , Tryptophan/pharmacology , Apoptosis/drug effects , Cardioplegic Solutions/chemistry , Caspases/analysis , Caspases/drug effects , Immunohistochemistry , /analysis , /drug effects , /analysis , /drug effects , Myocytes, Cardiac , Rats, Wistar , Reproducibility of Results , Time FactorsABSTRACT
OBJECTIVES: Apoptosis is the process of programmed cell death (PCD) that occurs in both animal and plant cells. Protozoan parasites possess metacaspase and these caspase-related proteases could be involved in the PCD pathways in these organisms. Therefore we analyzed the activities of metacaspase and PARP genes in Leishmania infantum (MCAN/IR/96/LON49) treated with miltefosine. MATERIALS AND METHODS: Anti-leishmania activity of miltefosine was studied by treatment of cultured promastigotes with various concentration of miltefosine. MTT assay and Annexin-V FLUOS staining by using FACS flow cytometry methods were used. Cytotoxic potential of HePC on the amastigots of L.infantum was evaluated in J774 cell line. In addition, metacaspase and PARP genes expression of treated L. infantum were studied. RESULTS: Miltefosine led to dose-dependent death of L. infantumwith features compatible with apoptosis. Over expression of metacaspase and PARP was seen 6 hr after treatment. CONCLUSIONS: Our study showed that miltefosine exerts cytotoxic effect on L. infantum via an apoptotic-related mechanism.
Subject(s)
Antiprotozoal Agents/pharmacology , Apoptosis/drug effects , Caspases/drug effects , Leishmania infantum/drug effects , Phosphorylcholine/analogs & derivatives , Poly(ADP-ribose) Polymerases/drug effects , Apoptosis/genetics , Colorimetry , Caspases/genetics , Flow Cytometry , Formazans/metabolism , Leishmania infantum/cytology , Leishmania infantum/genetics , Polymerase Chain Reaction , Phosphorylcholine/pharmacology , Poly(ADP-ribose) Polymerases/genetics , Tetrazolium Salts/metabolismABSTRACT
We investigated the role of protein tyrosine phosphatase-alpha (PTPα) expression in the cell death profile of the A431 human carcinoma cell line that was induced by cytotoxic concentrations of the nitric oxide (NO) donors sodium nitroprusside (SNP) and 3,3-bis-(aminoethyl)-1-hydroxy-2-oxo-1-triazene (NOC-18). Both NO donors promoted extensive cell detachment in A431 parental cells as compared to the detachment observed for A431 cells that ectopically expressed PTPα (A431 (A27B(PTPα)) cells). The NO-induced cell death characteristics for both cell lines were examined. After incubation for 10 hours with 2.0 mM SNP, attached or detached A431 cells underwent apoptosis. Cells were highly positive for Annexin-V, featured increased cleavage of procaspase-8, activation of downstream caspase-3, and activation of poly-ADP-ribose polymerase 1 (PARP-1). In contrast, exposure of A431 (A27B(PTPα)) cells to 2.0 mM SNP produced an increase in the release of lactate dehydrogenase and enhanced incorporation of propidium iodide. In addition, A431 (A27B(PTPα)) cells showed partial inhibition of the activities of caspase-8, caspase-3, and PARP-1 upon detachment and cell death induced by SNP treatment. Results indicate that necrotic cell damage was induced, characterized by cellular swelling and lysis. We conclude from these results that PTPα regulates the A431 tumor cell death profile mediated by NO donors. Expression of PTPα or its absence may determine the occurrence of NO-induced cell death with necrotic or apoptotic features, respectively.
Subject(s)
Apoptosis , Nitric Oxide Donors/pharmacology , Nitroprusside/pharmacology , Nitroso Compounds/pharmacology , Receptor-Like Protein Tyrosine Phosphatases, Class 4/metabolism , Caspases/drug effects , Cell Line, Tumor , Cell Membrane Permeability , Epithelial Cells/drug effects , Epithelial Cells/enzymology , Epithelial Cells/metabolism , Humans , L-Lactate Dehydrogenase/drug effects , Nitric Oxide/metabolism , Phosphatidylserines/analysis , Poly(ADP-ribose) Polymerases/drug effects , Propidium/analysis , Receptor-Like Protein Tyrosine Phosphatases, Class 4/genetics , TransfectionABSTRACT
OBJECTIVES: Apoptosis is the process of programmed cell death (PCD) that occurs in both animal and plant cells. Protozoan parasites possess metacaspase and these caspase-related proteases could be involved in the PCD pathways in these organisms. Therefore we analyzed the activities of metacaspase and PARP genes in Leishmania infantum (MCAN/IR/96/LON49) treated with miltefosine. MATERIALS AND METHODS: Anti-leishmania activity of miltefosine was studied by treatment of cultured promastigotes with various concentration of miltefosine. MTT assay and Annexin-V FLUOS staining by using FACS flow cytometry methods were used. Cytotoxic potential of HePC on the amastigots of L.infantum was evaluated in J774 cell line. In addition, metacaspase and PARP genes expression of treated L. infantum were studied. RESULTS: Miltefosine led to dose-dependent death of L. infantum with features compatible with apoptosis. Over expression of metacaspase and PARP was seen 6 hr after treatment. CONCLUSIONS: Our study showed that miltefosine exerts cytotoxic effect on L. infantum via an apoptotic-related mechanism.
Subject(s)
Antiprotozoal Agents/pharmacology , Apoptosis/drug effects , Caspases/drug effects , Leishmania infantum/drug effects , Phosphorylcholine/analogs & derivatives , Poly(ADP-ribose) Polymerases/drug effects , Apoptosis/genetics , Caspases/genetics , Colorimetry , Flow Cytometry , Formazans/metabolism , Leishmania infantum/cytology , Leishmania infantum/genetics , Phosphorylcholine/pharmacology , Poly(ADP-ribose) Polymerases/genetics , Polymerase Chain Reaction , Tetrazolium Salts/metabolismABSTRACT
Photoderivatives of riboflavin can modulate the proliferation and survival of cancer cells. In this work, we examined the influence of riboflavin and photoderivatives on osteoblast differentiation induced by ascorbic acid and ß-glycerophosphate. These compounds decreased the osteoblast proliferation, increased the alkaline phosphatase activity, promoted a reduction in matrix metalloproteinase-2 activity and the decreased in the OPG/RANKL ratio. The effects of flavins on osteoblasts were unrelated to the antioxidant activity of these compounds. The biological activity of osteogenic medium containing riboflavin and its photoderivatives involved the activation of different signaling pathways (AKT, FAK, CaMKII), caspases-3, -8 and -9, and up-regulation of the expression and/or stabilization of osteoblastic transcription factors (Runx2 and ß-catenin). These findings suggest a potential use of flavins as adjuvants to improve bone metabolism.
Subject(s)
Flavins/pharmacology , Photolysis , Riboflavin/pharmacology , Vitamin B Complex/pharmacology , 3T3 Cells , Animals , Caspases/drug effects , Caspases/metabolism , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Mice , Osteoblasts/metabolism , Riboflavin/chemistry , Signal Transduction/drug effects , Up-Regulation/drug effects , Vitamin B Complex/chemistryABSTRACT
p,p'-Dichlorodiphenyldichloroethylene (DDE), the most stable metabolite of organochlorine insecticide p,p'-dichlorodiphenyltrichloroethane (DDT), has been detected in human populations living in malaria-endemic areas of México where this insecticide was used. DDE induces apoptosis in peripheral blood mononuclear cells (PMBC); however, the molecular mechanism of cell death induced by this compound is poorly understood. In the present study, PBMC isolated from healthy individuals (not exposed to DDE) were incubated in the presence of increasing concentrations of p,p'-DDE (0-80 microg/ml) over time. When PBMC were treated with low p,p'-DDE concentration (10 microg/ml) an antioxidant response and biomarkers of inflammation were induced, indicating a pro-inflammatory state. Moreover, when PBMC were treated with high p,p'-DDE concentration (80 microg/ml) several apoptotic biochemical events were triggered, such as activation of caspase-8, Bid, caspase-9 and caspase-3, as well as degradation of PARP and ubiquitination. The results described in this study show a possible inflammatory condition and the involvement of both extrinsic and intrinsic pathways in the induction of apoptosis in DDE-treated PBMC.
Subject(s)
Apoptosis/drug effects , Dichlorodiphenyl Dichloroethylene/toxicity , Insecticides/toxicity , Adult , BH3 Interacting Domain Death Agonist Protein/metabolism , Biomarkers/metabolism , Caspases/drug effects , Caspases/metabolism , Dichlorodiphenyl Dichloroethylene/administration & dosage , Dose-Response Relationship, Drug , Humans , In Vitro Techniques , Inflammation/chemically induced , Insecticides/administration & dosage , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/metabolism , Poly (ADP-Ribose) Polymerase-1 , Poly(ADP-ribose) Polymerases/drug effects , Poly(ADP-ribose) Polymerases/metabolism , Ubiquitination/drug effects , Young AdultABSTRACT
Manganese induces the central nervous system injury leading to manganism, by mechanisms not completely understood. Chronic exposure to manganese generates oxidative stress and induces the mitochondrial permeability transition. In the present study, we characterized apoptotic cell death mechanisms associated with manganese toxicity in rat cortical astrocytes and demonstrated that (i) Mn treatment targets the mitochondria and induces mitochondrial membrane depolarization followed by cytochrome c release to the cytoplasm, (ii) Mn induces both effector caspases 3/7 and 6 as well as PARP-1 cleavage and (iii) Mn shifts the balance of cell death/survival of Bcl-2 family proteins to favor the apoptotic demise of astrocytes. Our model system using cortical rat astrocytes treated with Mn would emerge as a good tool for investigations aimed to elucidate the role of apoptosis in manganism.
Subject(s)
Apoptosis/drug effects , Astrocytes/drug effects , Manganese Poisoning/physiopathology , Manganese/toxicity , Mitochondria/drug effects , Proto-Oncogene Proteins c-bcl-2/drug effects , Animals , Animals, Newborn , Apoptosis/physiology , Astrocytes/metabolism , Caspases/drug effects , Caspases/metabolism , Cells, Cultured , Central Nervous System/drug effects , Central Nervous System/metabolism , Central Nervous System/physiopathology , Manganese Poisoning/metabolism , Membrane Potential, Mitochondrial/drug effects , Membrane Potential, Mitochondrial/physiology , Mitochondria/metabolism , Models, Biological , Poly (ADP-Ribose) Polymerase-1 , Poly(ADP-ribose) Polymerases/drug effects , Poly(ADP-ribose) Polymerases/metabolism , Proto-Oncogene Proteins c-bcl-2/metabolism , Rats , Rats, Sprague-Dawley , Signal Transduction/drug effects , Signal Transduction/physiology , bcl-2-Associated X Protein/drug effects , bcl-2-Associated X Protein/metabolism , bcl-X Protein/drug effects , bcl-X Protein/metabolismABSTRACT
Temporal lobe epilepsy is the most common form of epilepsy in humans. Caspase activation is a mechanism of cell death induced by seizures. Tellurium (IV) compounds present antitumoral, immunomodulatory and neuroprotective effects due to their ability to inhibit cysteine proteases. We studied the activity of caspase-1, -3 and -8 in the hippocampus of rats exhibiting status epilepticus induced by pilocarpine. All three caspases were activated. Tellurium (IV) compounds RF-07, RF-03 and AS-101 inhibited caspases in vitro, showing high second-order inhibition rate constants. The intraperitoneal injection of RF-07 prior to pilocarpine suppressed the behavioral and electroencephalographic seizure occurrence. According to our results, the caspases are activated as early as 90 min following SE. Tellurium (IV) compounds exerted anticonvulsant effects associated with the inhibition of caspases. These results suggest a promising therapeutic potential of organotellurium (IV) compounds as antiepileptogenic agents.
Subject(s)
Anticonvulsants/pharmacology , Caspases/drug effects , Hippocampus/drug effects , Status Epilepticus/enzymology , Tellurium/pharmacology , Animals , Caspases/metabolism , Electroencephalography , Enzyme Activation/drug effects , Enzyme Inhibitors/pharmacology , Ethylenes/pharmacology , Hippocampus/enzymology , Male , Muscarinic Agonists/toxicity , Pilocarpine/toxicity , Rats , Rats, WistarABSTRACT
CD95 (Fas/Apo-1)-mediated apoptosis was shown to occur through two distinct pathways. One involves a direct activation of caspase-3 by large amounts of caspase-8 generated at the DISC (Type I cells). The other is related to the cleavage of Bid by low concentration of caspase-8, leading to the release of cytochrome c from mitochondria and the activation of caspase-3 by the cytochrome c/APAF-1/caspase-9 apoptosome (Type II cells). It is also known that the protein synthesis inhibitor cycloheximide (CHX) sensitizes Type I cells to CD95-mediated apoptosis, but it remains contradictory whether this effect also occurs in Type II cells. Here, we show that sub-lethal doses of CHX render both Type I and Type II cells sensitive to the apoptogenic effect of anti-CD95 antibodies but not to chemotherapeutic drugs. Moreover, Bcl-2-positive Type II cells become strongly sensitive to CD95-mediated apoptosis by the addition of CHX to the cell culture. This is not the result of a restraint of the anti-apoptotic effect of Bcl-2 at the mitochondrial level since CHX-treated Type II cells still retain their resistance to chemotherapeutic drugs. Therefore, CHX treatment is granting the CD95-mediated pathway the ability to bypass the mitochondria requirement to apoptosis, much alike to what is observed in Type I cells.
Subject(s)
Apoptosis Regulatory Proteins/metabolism , Apoptosis/physiology , Mitochondria/metabolism , Signal Transduction/physiology , fas Receptor/metabolism , Antibodies/pharmacology , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Apoptosis Regulatory Proteins/antagonists & inhibitors , BH3 Interacting Domain Death Agonist Protein/drug effects , BH3 Interacting Domain Death Agonist Protein/metabolism , Caspases/drug effects , Caspases/metabolism , Cycloheximide/pharmacology , Cytochromes c/drug effects , Cytochromes c/metabolism , Dose-Response Relationship, Drug , Drug Resistance, Neoplasm/drug effects , Drug Resistance, Neoplasm/physiology , Drug Synergism , HL-60 Cells , Humans , Mitochondria/drug effects , Protein Synthesis Inhibitors/pharmacology , Proto-Oncogene Proteins c-bcl-2/drug effects , Proto-Oncogene Proteins c-bcl-2/metabolism , Signal Transduction/drug effects , fas Receptor/antagonists & inhibitorsABSTRACT
Infection with Trypanosoma cruzi causes expansion of subcutaneous (SLN) and atrophy of mesenteric (MLN) lymph nodes. Here we show that excision of MLN increased parasitemia in T. cruzi-infected mice. We then studied how apoptosis of MLN cells affects immune responses to infection. T cell apoptosis increased in the MLN compared to SLN in T. cruzi-infected mice. Absolute numbers of naïve T cells decreased, and activated T cells failed to accumulate in MLN during infection. In addition, activated T cells from MLN produced less IL-2, IFN-gamma, IL-4, and IL-10 than T cells from SLN. Treatment with IL-4 or with caspase-9 inhibitor increased the recovery of viable T cells in vitro. Treatment with caspase-9 inhibitor also increased the production of cytokines by MLN T cells from infected mice. Moreover, injection of a pan caspase inhibitor prevented MLN atrophy during T. cruzi infection. Caspase-9, but not caspase-8, inhibitor also reduced MLN atrophy and increased the recovery of naïve and activated T cells from MLN. These findings indicate that caspase-mediated apoptosis and defective cytokine production are implicated in MLN atrophy and affect immune responses to T. cruzi infection.
Subject(s)
Apoptosis/immunology , Chagas Disease/immunology , Lymph Nodes/immunology , Mesentery/immunology , Skin/immunology , T-Lymphocytes/immunology , Animals , Atrophy , Caspases/drug effects , Caspases/immunology , Caspases/metabolism , Cytokines/biosynthesis , Enzyme Inhibitors/pharmacology , Enzyme-Linked Immunosorbent Assay , Flow Cytometry , Lymph Nodes/microbiology , Lymph Nodes/pathology , Lymphocyte Activation/immunology , Male , Mice , Mice, Inbred BALB C , T-Lymphocytes/microbiology , T-Lymphocytes/pathology , Trypanosoma cruziABSTRACT
Two hepatoma cell lines were incubated for 72 h with ATRA and its analog 13cisRA and according to MTT assay, Hep3B cells were highly susceptible whereas HepG2 cells were more resistant to the treatment. At the high concentration of 166 microM, retinoids were able to induce apoptosis in both cell lines and the highest effect was observed in HepG2 cells treated with ATRA. TUNEL-based photometric ELISA showed that at the same retinoid concentration tested by flow cytometry, both cell lines showed apoptosis whereas plasma membranes were not significantly disrupted. Inhibitors of apoptosis Bcl-xL and survivin were downregulated in Hep3B cells by treatment with both retinoids. Bax, a pro-apoptotic protein, was not significantly upregulated in Hep3B cells, but was slightly increased in HepG2 cells treated with 13cisRA. Both procaspase-3 and procaspase-8 were cleaved in Hep3B cells, suggesting apoptosis could be triggered through the extrinsic pathway. In the case of HepG2 cells, lack of caspase activation suggests a mechanism dependent on other kind of proteases.