RESUMO
Sodium dichloroacetate (DCA) is a metabolic regulator used to treat diabetes. Since DCA inhibits pyruvate dehydrogenase kinase, decreasing lactic acid formation, it can reverse the Warburg effect in cancer cells, promoting apoptosis. Therefore, this study aimed to investigate the potential of DCA as a drug repurposing candidate for the treatment of melanoma. For the in-vitro assay, murine B16-F10 melanoma cells were treated with 0.5, 1, 5, 10, 20 or 50 mM DCA for 3 days, analyzed with the crystal violet method. The in-vivo effect of DCA was evaluated in B16-F10 tumor-bearing C57BL/6 mice treated with different doses of DCA (0, 25, 75 or 150 mg/kg) by gavage for 10 days, followed by measurement of tumor volume. Upon necropsy, representative slices of lung, liver, kidney, spleen and intestine were collected, processed and submitted for histopathological examination. The DCA concentrations of 10, 20 and 50 mM reduced B16-F10 cell viability after 48 and 72 h of treatment, whereas 20 and 50 mM were effective after 24 h of treatment. A significant reduction in tumor growth was observed in B16-F10 melanoma bearing mice at all doses, with no change in body weight or histology. DCA attenuates the growth of B16-F10 melanoma in vitro and in vivo, without systemic toxic effects. Therefore, DCA is a candidate for drug repurposing against melanomas.
Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Ácido Dicloroacético/farmacologia , Ácido Dicloroacético/uso terapêutico , Melanoma Experimental/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Animais , Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ácido Dicloroacético/administração & dosagem , Relação Dose-Resposta a Droga , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Carga Tumoral/efeitos dos fármacosRESUMO
A hypoxic microenvironment is a hallmark in different types of tumors; this phenomenon participates in a metabolic alteration that confers resistance to treatments. Because of this, it was proposed that a combination of 2-methoxyestradiol (2-ME) and sodium dichloroacetate (DCA) could reduce this alteration, preventing proliferation through the reactivation of aerobic metabolism in lung adenocarcinoma cell line (A549). A549 cells were cultured in a hypoxic chamber at 1% O2 for 72 hours to determine the effect of this combination on growth, migration, and expression of hypoxia-inducible factors (HIFs) by immunofluorescence. The effect in the metabolism was evaluated by the determination of glucose/glutamine consumption and the lactate/glutamate production. The treatment of 2-ME (10 µM) in combination with DCA (40 mM) under hypoxic conditions showed an inhibitory effect on growth and migration. Notably, this reduction could be attributed to 2-ME, while DCA had a predominant effect on metabolic activity. Moreover, this combination decreases the signaling of HIF-3α and partially HIF-1α but not HIF-2α. The results of this study highlight the antitumor activity of the combination of 2-ME 10 µl/DCA 40 mM, even in hypoxic conditions.
Assuntos
2-Metoxiestradiol/uso terapêutico , Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Ácido Dicloroacético/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Hipóxia Tumoral , Microambiente Tumoral , 2-Metoxiestradiol/farmacologia , Células A549 , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Proteínas Reguladoras de Apoptose/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ácido Dicloroacético/farmacologia , Glucose/metabolismo , Ácido Glutâmico/metabolismo , Glutamina/metabolismo , Glicólise/efeitos dos fármacos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Ácido Láctico/metabolismo , Neoplasias Pulmonares/patologia , Proteínas Repressoras/metabolismo , Transdução de Sinais/efeitos dos fármacos , Hipóxia Tumoral/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Cicatrização/efeitos dos fármacosRESUMO
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by motor neuron (MN) degeneration and gliosis. Neonatal astrocytes obtained from the SOD1G93A rat model of ALS exhibit mitochondrial dysfunction and neurotoxicity that can be reduced by dichloroacetate (DCA), a metabolic modulator that has been used in humans, and shows beneficial effects on disease outcome in SOD1G93A mice. Aberrant glial cells (AbGC) isolated from the spinal cords of adult paralytic SOD1G93A rats exhibit highly proliferative and neurotoxic properties and may contribute to disease progression. Here we analyze the mitochondrial activity of AbGC and whether metabolic modulation would modify their phenotypic profile. Our studies revealed fragmented mitochondria and lower respiratory control ratio in AbGC compared to neonatal SOD1G93A and nontransgenic rat astrocytes. DCA (5 mM) exposure improved AbGC mitochondrial function, reduced their proliferative rate, and importantly, decreased their toxicity to MNs. Furthermore, oral DCA administration (100 mg/kg, 10 days) to symptomatic SOD1G93A rats reduced MN degeneration, gliosis, and the number of GFAP/S100ß double-labeled hypertrophic glial cells in the spinal cord. DCA treatment of AbGC reduced extracellular lactate levels indicating that the main recognized DCA action, targeting the pyruvate dehydrogenase kinase/pyruvate dehydrogenase complex, may underlie our findings. Our results show that AbGC metabolic phenotype is related to their toxicity to MNs and indicate that its modulation can reduce glial mediated pathology in the spinal cord. Together with previous findings, these results further support glial metabolic modulation as a valid therapeutic strategy in ALS.
Assuntos
Esclerose Lateral Amiotrófica , Ácido Dicloroacético/farmacologia , Gliose , Mitocôndrias , Superóxido Dismutase , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Modelos Animais de Doenças , Gliose/metabolismo , Gliose/patologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Neuroglia/ultraestrutura , Ratos , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Medula Espinal/patologiaRESUMO
Introdução: A cirurgia micrográfica de Mohs é empregada para exérese de neoplasias cutâneas, especialmente carcinomas basocelulares de subtipos histológicos localmente agressivos, tumores recidivados ou localizados em regiões nobres. Apresenta elevados índices de cura e permite preservação tecidual. O objetivo é analisar a eficácia da cirurgia micrografia de Mohs e os métodos de reconstrução utilizados. Método: Foram coletados, retrospectivamente, dados de 50 pacientes submetidos à exérese de tumores cutâneos por meio da cirurgia micrográfica de Mohs e à reconstrução da perda de substância. Todos os pacientes foram operados no período entre janeiro de 2005 a dezembro de 2013 na Clínica de Cirurgia Plástica do Hospital Felício Rocho (Belo Horizonte, MG, Brasil). Os pacientes foram estudados com relação à idade, gênero, localização do tumor, tratamento prévio, tipo histológico, número de fragmentos analisados na cirurgia micrográfica, método de reconstrução empregado e proservação. Resultados: Trinta e um pacientes (62%) foram do gênero feminino e 19 (38%) do masculino. A média de idade foi de 63,8 anos. Todas as lesões encontravam-se na face, com 66% dos casos com acometimento da região nasal. Considerando o diagnóstico pré-operatório, 48 casos (96%) eram carcinoma basocelulares e dois casos (4%) correspondiam ao carcinoma microcístico anexial. Retalhos locais foram o tipo de reconstrução mais utilizado. Os pacientes foram acompanhados por média de 48,4 meses. Nenhum caso de recidiva tumoral foi observado. Conclusão: A cirurgia micrográfica de Mohs se mostrou altamente eficaz no tratamento dos 50 casos de neoplasias cutâneas. Recomenda-se que os defeitos cirúrgicos sejam reparados pelo cirurgião plástico.
Introduction: Mohs micrographic surgery is used for the excision of skin neoplasms, especially in locally aggressive histological subtypes of basal cell carcinoma, tumor recurrences, or tumors located in critical areas . This technique has a high cure rate and allows maximum preservation of tissues. In this study, we aimed to assess the effectiveness of Mohs micrographic surgery and reconstruction methods. Method: Data from 50 patients who underwent Mohs micrographic surgery to excise skin tumors and reconstruct lost tissue were collected retrospectively. All patients were operated on between January 2005 and December 2013 at the Plastic Surgery Clinic of the Felício Rocho Hospital (Belo Horizonte, MG, Brazil). The patients' age, sex, tumor location, previous treatment, histological type, number of segments analyzed by micrographic surgery, reconstruction method used, and preservation were studied. Results: Thirtyone patients (62%) were women and 19 (38%) were men. The mean age was 63.8 years. All lesions were facial, with 66% of cases affecting the nasal area. Pre-surgery, there were 48 cases (96%) of basal cell carcinoma and 2 cases (4%) of microcystic adnexal carcinoma. Local flaps were the most used reconstruction method. The patients were followed-up for a mean of 48.4 months. We did not observe any cases of tumor recurrence. Conclusion: Mohs micrographic surgery was shown to be effective in the treatment of 50 skin neoplasms. We recommend that surgical defects should be repaired by the plastic surgeon.
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , História do Século XXI , Neoplasias Cutâneas , Ferimentos e Lesões , Carcinoma Basocelular , Prontuários Médicos , Eficácia , Interpretação Estatística de Dados , Cirurgia de Mohs , Procedimentos de Cirurgia Plástica , Estudo de Avaliação , Ácido Dicloroacético , Neoplasias de Cabeça e Pescoço , Neoplasias Cutâneas/cirurgia , Neoplasias Cutâneas/patologia , Ferimentos e Lesões/cirurgia , Ferimentos e Lesões/complicações , Carcinoma Basocelular/cirurgia , Carcinoma Basocelular/patologia , Prontuários Médicos/normas , Eficácia/métodos , Cirurgia de Mohs/efeitos adversos , Cirurgia de Mohs/métodos , Procedimentos de Cirurgia Plástica/métodos , Ácido Dicloroacético/efeitos adversos , Ácido Dicloroacético/uso terapêutico , Ácido Dicloroacético/farmacologia , Neoplasias de Cabeça e Pescoço/cirurgia , Neoplasias de Cabeça e Pescoço/patologiaRESUMO
Mitochondrial dysfunction is one of the pathogenic mechanisms that lead to neurodegeneration in Amyotrophic Lateral Sclerosis (ALS). Astrocytes expressing the ALS-linked SOD1(G93A) mutation display a decreased mitochondrial respiratory capacity associated to phenotypic changes that cause them to induce motor neuron death. Astrocyte-mediated toxicity can be prevented by mitochondria-targeted antioxidants, indicating a critical role of mitochondria in the neurotoxic phenotype. However, it is presently unknown whether drugs currently used to stimulate mitochondrial metabolism can also modulate ALS progression. Here, we tested the disease-modifying effect of dichloroacetate (DCA), an orphan drug that improves the functional status of mitochondria through the stimulation of the pyruvate dehydrogenase complex activity (PDH). Applied to astrocyte cultures isolated from rats expressing the SOD1(G93A) mutation, DCA reduced phosphorylation of PDH and improved mitochondrial coupling as expressed by the respiratory control ratio (RCR). Notably, DCA completely prevented the toxicity of SOD1(G93A) astrocytes to motor neurons in coculture conditions. Chronic administration of DCA (500 mg/L) in the drinking water of mice expressing the SOD1(G93A) mutation increased survival by 2 weeks compared to untreated mice. Systemic DCA also normalized the reduced RCR value measured in lumbar spinal cord tissue of diseased SOD1(G93A) mice. A remarkable effect of DCA was the improvement of grip strength performance at the end stage of the disease, which correlated with a recovery of the neuromuscular junction area in extensor digitorum longus muscles. Systemic DCA also decreased astrocyte reactivity and prevented motor neuron loss in SOD1(G93A) mice. Taken together, our results indicate that improvement of the mitochondrial redox status by DCA leads to a disease-modifying effect, further supporting the therapeutic potential of mitochondria-targeted drugs in ALS.
Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Astrócitos/efeitos dos fármacos , Ácido Dicloroacético/farmacologia , Mitocôndrias/efeitos dos fármacos , Neurônios Motores/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/genética , Animais , Astrócitos/metabolismo , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Mitocôndrias/fisiologia , Oxirredução/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Complexo Piruvato Desidrogenase/metabolismo , Ratos , Superóxido Dismutase/genética , Superóxido Dismutase-1RESUMO
INTRODUCTION: Chemotherapy for advanced well-differentiated carcinoids is characterised by low response rates and short duration of responses. The present study aimed to assess the in vitro activity of novel platinum-based chemotherapeutic drugs in combination with dichloroacetate (DCA), a sensitiser to apoptosis, against lung carcinoid cell lines. METHODS: Three permanent cell lines (UMC-11, H727 and H835) were exposed to 14 different established cytotoxic drugs and the novel platinum-based compounds as satraplatin, JM118 and picoplatin in combination with DCA, and viability of the cells was measured using a tetrazoliumbased dye assay. RESULTS: With exception of the highly chemoresistant UMC- 11 line, the carcinoid cell lines (H727, H835) were sensitive to the majority of chemotherapeutics in vitro. Among the platinum-based drugs, carboplatin and oxaliplatin showed highest efficacy. H835 cells growing as multicellular spheroids were 2.7-8.7-fold more resistant to picoplatin, satraplatin and its metabolite compared to single cell suspensions. DCA (10 mM) inhibited the growth of UMC- 11 cells by 22% and sensitised these highly resistant cells to carboplatin, satraplatin and JM118 1.4-2.4-fold. CONCLUSION: The highly resistant UMC-11 lung carcinoid cells are sensitive to carboplatin, oxaliplatin and the satraplatin metabolite JM118, but multicellular spheroidal growth, as observed in the H835 cell line and pulmonary tumourlets, seems to increase chemoresistance markedly. The activity of carboplatin and JM118 is significantly and specifically increased in combination with the apoptosis sensitiser DCA that promotes mitochondrial respiration over aerobic glycolysis. In summary, among the novel platinum drugs satraplatin has the potential for treatment of lung carcinoids and DCA potentiates the cytotoxicity of selected platinum drugs.
Assuntos
Tumor Carcinoide/patologia , Ácido Dicloroacético/farmacologia , Neoplasias Pulmonares/patologia , Compostos de Platina/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Tumor Carcinoide/tratamento farmacológico , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citotoxinas/administração & dosagem , Citotoxinas/farmacologia , Ácido Dicloroacético/administração & dosagem , Avaliação Pré-Clínica de Medicamentos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/farmacologia , Compostos de Platina/administração & dosagemRESUMO
The effectiveness of drug therapy in controlling angina and the resulting improvement in exercise capacity were reviewed. We performed a Medline search of published reports on ranolazine, trimetazidine, and other medicines that act metabolically. Quality of life with regards to work capacity alone was analyzed. Most reports were about trimetazidine, with strong evidence of its efficacy and tolerability. Its effect on episodes of angina, total exercise time, and time to the onset of ischemia on ECG is impressive with no negative effects found on double product (workload) and improvement in quality of life. The second most evaluated drug was ranolazine, particularly regarding quality of life. Results are similar to those with trimetazidine but are not as significant for quality of life issues. For the other drugs, L-carnitine, ribose, and dichloroacetate, accumulated experimental data provide a physiological background in which clinical trials have been started, but as yet very few patients have been enrolled. Also, studies that intended to evaluate, by echocardiography, ischemic dysfunction induced by dobutamine-atropine stress were examined; these also showed a reduction in ischemia and fewer anginal episodes, but only with trimetazidine in this regard. Taken together, these drug effects are important to ameliorate quality of life. The issue of quality of life was evaluated in specific reports, and the results of the application of validated questionnaires (SF36, 5-dimensional EuroQol Instrument, and Seattle Angina Questionnaire) attest to the positive drug effects on patients' perception of wellness, particularly with the use of trimetazidine, and less with ranolazine.
Assuntos
Angina Pectoris/tratamento farmacológico , Doença da Artéria Coronariana/tratamento farmacológico , Vasodilatadores/uso terapêutico , Acetanilidas/farmacologia , Acetanilidas/uso terapêutico , Angina Pectoris/metabolismo , Animais , Carnitina/farmacologia , Carnitina/uso terapêutico , Ensaios Clínicos como Assunto , Doença da Artéria Coronariana/metabolismo , Ácido Dicloroacético/farmacologia , Ácido Dicloroacético/uso terapêutico , Humanos , Piperazinas/farmacologia , Piperazinas/uso terapêutico , Qualidade de Vida , Ranolazina , Ribose/farmacologia , Ribose/uso terapêutico , Inquéritos e Questionários , Trimetazidina/farmacologia , Trimetazidina/uso terapêutico , Vasodilatadores/farmacologiaRESUMO
In the present study, we tested the hypothesis that lactate, which is a classic companion of hypoxic stress in mammals, is a modulator of hypoxia-induced hyperventilation. To this end, pulmonary ventilation (V(E)) of male Wistar rats was measured by whole body plethysmograph, and dichloroacetate (DCA, 100 mg/kg) was used to inhibit lactate production. Plasma lactate levels, arterial pH (pHa), arterial carbon dioxide partial pressure (PaCO(2)), arterial oxygen partial pressure (PaO(2)), plasma bicarbonate (HCO3(-)) and oxygen consumption (VO(2)) were determined as well. In normoxia, intraperitoneal DCA elicited a decrease only in plasma lactate levels. Hypoxia caused an increase in V(E), pHa and plasma lactate levels and parallel to decreases in PaCO(2), PaO(2) and VO(2) in the control group. DCA administration markedly reduced the ventilatory response to hypoxia by acting on tidal volume (V(T)). This reduced ventilatory response caused by DCA was independent of VO(2). In conclusion, the present study indicates that lactate contributes to the initiation and maintenance of hypoxia-induced hyperventilation in rats, modulating the adjustments in V(T).
Assuntos
Ácido Dicloroacético/farmacologia , Hiperventilação/metabolismo , Hipóxia/metabolismo , Ácido Láctico/sangue , Respiração/efeitos dos fármacos , Acidose Láctica/tratamento farmacológico , Animais , Inibidores Enzimáticos/farmacologia , Hipóxia/diagnóstico , Masculino , Consumo de Oxigênio , Ventilação Pulmonar/efeitos dos fármacos , Ratos , Ratos WistarRESUMO
Hypoxia causes a regulated decrease in body core temperature ( T(c)), termed anapyrexia, which seems to be a very effective way of preventing hypoxia-associated cell damage. Since during several pathological states the supply of O(2) is a limiting factor, the clinical importance of anapyrexia is evident. However, the mechanisms involved in this response remain unclear. We tested the hypothesis that lactate, a classic companion of hypoxia, is a mediator of hypoxia-induced anapyrexia, using the inhibitor of acid lactic production dichloroacetate (DCA). Each of 28 rats was placed in a chamber ventilated with humidified air at an ambient temperature of 24-26 degrees C. After a control period of 30 min the animals were given saline or 100 mg/kg DCA i.p. Then, 30 min later, the chamber was flushed with a 7% O(2) gas mixture for 2 h. At the end of the experiment, the animals were decapitated and blood samples collected for measurements of plasma lactate. T(c) was measured by biotelemetry. DCA did not affect the T(c) or basal lactate levels of normoxic rats. Hypoxia elicited a significant decrease in T(c) and an increase in plasma lactate levels. Although DCA decreased plasma lactate levels during hypoxia, it caused no change in the course of hypoxia-induced anapyrexia. Correspondingly, no correlation was found between the drop in T(c) and the rise in plasma lactate during hypoxic conditions. These results do not support the hypothesis that lactate is a mediator of hypoxia-induced anapyrexia in rats.
Assuntos
Regulação da Temperatura Corporal/fisiologia , Febre/metabolismo , Hipóxia/metabolismo , Ácido Láctico/sangue , Animais , Temperatura Corporal/efeitos dos fármacos , Temperatura Corporal/fisiologia , Regulação da Temperatura Corporal/efeitos dos fármacos , Ácido Dicloroacético/farmacologia , Masculino , Oxigênio/metabolismo , Ratos , Ratos WistarRESUMO
Clinical findings are presented for 30 patients with lactic acidemia in whom activity of the pyruvate dehydrogenase complex in fibroblasts was significantly (P = less than 0.01) below that of control cell lines. Residual activity of the activated complex ranged from 1.6% to 68.5% of control activity. Seven patients died before 6 months of age, and another five before reaching 2 years of age. Sixteen of the surviving patients and the five who died between 6 months and 2 years all had psychomotor retardation. Seventeen children had structural central nervous system damage, as determined either by computed tomography or at autopsy. The extent and location of damage varied from cerebral atrophy to the development of cystic lesions in the cerebral cortex, basal ganglia, and brain stem. Two patients had ataxic episodes only and were not developmentally delayed. This cohort of patients strongly resembles a comparable group assembled from various other reports.