ABSTRACT
ABSTRACT BACKGROUND: Gastric cancer is known as the fourth most common cancer. Current treatments for cancer have damaged the sensitive tissues of the healthy body, and in many cases, cancer will be recurrent. Therefore, need for treatments that are more effective is well felt. Researchers have recently shifted their attention towards antipsychotic dopamine antagonists to treat cancer. The anticancer activities of aripiprazole remain unknown. OBJECTIVE: This study aimed to evaluate the efficacy and safety of aripiprazole on gastric cancer and normal cell lines. METHODS: In this regard, the cytotoxicity and genotoxicity of aripiprazole were investigated in MKN45 and NIH3T3 cell lines by methyl tetrazolium assay and on peripheral blood lymphocytes by micronucleus assay. For this purpose, cells were cultured in 96 wells plate. Stock solutions of aripiprazole and cisplatin were prepared. After cell incubation with different concentrations of aripiprazole (1, 10, 25, 50, 100 and 200 μL), methyl tetrazolium solution was added. For micronucleus assay fresh blood was added to RPMI culture medium 1640 supplemented, and different concentrations of aripiprazole (50, 100 and 200 μL) were added. RESULTS: The finding of present study showed that the IC50 of aripiprazole in the cancer cell line (21.36 μg/mL) was lower than that in the normal cell line (54.17 μg/mL). Moreover, the micronucleus assay showed that the frequency of micronuclei of aripiprazole at concentrations below 200 μM was much less than cisplatin. CONCLUSION: Aripiprazole can be a good cytotoxic compound and good candidate for further studies of cancer therapy.
RESUMO CONTEXTO: O câncer gástrico é conhecido como o quarto câncer mais comum. Os tratamentos atuais para o câncer danificaram os tecidos sensíveis do corpo saudável e, em muitos casos, o cancro será recorrente. Portanto, a necessidade de tratamentos que são mais eficazes é desejada. Recentemente, os pesquisadores mudaram sua atenção para os antagonistas antipsicóticos da dopamina para tratar o câncer. As atividades anticâncer de aripiprazol permanecem desconhecidas. OBJETIVO: Este estudo objetivou avaliar a eficácia e a segurança do aripiprazol no câncer gástrico e nas linhagens celulares normais. MÉTODOS: A este respeito, a citotoxicidade e a genotoxicidade do aripiprazol foram investigadas em linhas celulares MKN45 e NIH3T3 por ensaio de metil tetrazólio e em linfócitos periféricos de sangue por ensaio de micronúcleos. Para este efeito, as células foram cultivadas em 96 placas. As soluções de estoque de aripiprazol e cisplatina foram preparadas. Após incubação celular com diferentes concentrações de aripiprazol (1, 10, 25, 50, 100 e 200 μL), a solução de metil tetrazólio foi adicionada. Para o ensaio do micronúcleo o sangue fresco foi adicionado ao meio de cultura RPMI 1640 suplementado, e as concentrações diferentes de aripiprazole (50, 100 e 200 μL) foram adicionadas. RESULTADOS: O presente estudo mostrou que o IC50 de aripiprazol na linhagem celular cancerosa (21,36 μg/mL) foi menor do que na linha celular normal (54,17 μg/ mL). Além disso, o ensaio de micronúcleos demonstrou que a frequência de micronúcleos de aripiprazol em concentrações inferiores a 200 μM foi muito inferior à cisplatina. CONCLUSÃO: O aripiprazol pode ser um bom composto citotóxico e bom candidato para estudos adicionais da terapia do câncer.
Subject(s)
Humans , Animals , Mice , Lymphocytes/drug effects , Aripiprazole/toxicity , Micronucleus Tests/methods , NIH 3T3 Cells/drug effects , Mutagenicity TestsABSTRACT
MTT assay is commonly used to assess the cellular cytotoxicity caused by anticancer drugs in glioblastomas. However, there have been some reports insisting that MTT assay exhibited non-specific intracellular reduction of tetrazolium which led to underestimated results of cytotoxicity. Here, we examine whether or not MTT assay can lead to incorrect information regarding alcohol-induced cytotoxicity on immortalized and primary glioblastoma cells. MTT assay was applied to assess the ethanol-induced cytotoxicity at various ethanol concentrations. The cellular cytotoxicity induced by different doses of ethanol was analyzed and compared through several cytotoxic assays. Ethanol-induced cytotoxicity observed through MTT assay on both cell types was shown to be ethanol dose-dependent below a 3% concentration. However, the cytotoxicity was shown to be markedly underestimated only in primary cells at a 5% concentration. RT-PCR and Western Blot showed increased expressions of pro-apoptotic proteins and decreased expressions of anti-apoptotic proteins in an ethanol dose-dependent manner in both cell types. Furthermore, we present a possible mechanism for the unreliable result of MTT assay. A high concentration of ethanol induces more severe membrane damage and increased intracellular concentration of NADH in primary cells which enhances the nonspecific reduction of tetrazolium salt. Together, our findings demonstrate that the cytotoxicity on primary cells could inaccurately be assessed when detected through MTT assay. Therefore, a careful interpretation is needed when one would analyze the cytotoxic results of MTT assay, and it is suggested that other assays must be accompanied to produce more reliable and accurate cytotoxic results on primary glioblastoma cells.
Subject(s)
Apoptosis Regulatory Proteins , Blotting, Western , Ethanol , Glioblastoma , Membranes , NAD , Tetrazolium SaltsABSTRACT
El presente estudio evaluó el desempeño de dos sales de tetrazolio, una tradicional: INT y una de nueva generación: XTT, para estimar la densidad de microorganismos degradadores de hidrocarburos (HCs) en suelos empleando la técnica del Número Más Probable (NMP). Se analizaron 96 muestras de suelo provenientes de la Ecorregión Cafetera de Colombia. Los microorganismos fueron recuperados en agar mínimo de sales en atmósfera saturada de HCs y la capacidad degradadora fue confirmada por repiques sucesivos utilizando diesel como fuente de carbono. No se observaron diferencias significativas en los recuentos de microorganismos degradadores obtenidos con las dos sales (t de Student, p < 0,05), pero el XTT permitió mejor visualización de los pozos positivos dada la solubilidad del producto reducido, mientras que el INT produjo precipitación, debido al formazán insoluble generado, dificultando su lectura. Se obtuvo un mayor porcentaje de aislamientos empleando XTT (67%), lo cual podría indicar que el tipo de sal es determinante en la viabilidad de estas bacterias. Adicionalmente, se evaluó el límite de detección celular, las condiciones óptimas de concentración de XTT y el tiempo de incubación necesario para la detección de actividad degradadora utilizando la cepa Acinetobacter sp. El aumento en la concentración de XTT de 0,5 mM a 2 mM y el tiempo de incubación tuvieron un efecto inhibitorio y favorable respectivamente, en la recuperación de células viables, adicionalmente, límite de detección de la técnica fue de 10² UFC/ml.
The objective of this study was to evaluate the performance of two tetrazolium indicators: a traditional one: INT and a new generation one: XTT, for the estimation of hydrocarbon (HC) degrading microorganism s density using the Most Probable Number Technique (MPN). Ninety six composite soil samples were taken and analyzed from Ecorregión Cafetera Colombiana. Degrading microorganisms were recovered in minimum salt medium with saturated HC atmosphere. Degrading HC capacity of the microorganisms was confirmed by successive subcultures in the same medium using diesel as only carbon source. Counts obtained with the two salts were not significantly different (Student t test, p < 0,05) but XTT allowed an easier visualization of positive wells due to product solubility of the reduce product. A greater percentage of isolates was obtained using XTT (67%), which suggests that salt type is relevant for recovering of these microorganisms. Additionally, cell detection limit, optimal conditions of XTT concentration and incubation times for detection of activity were evaluated. This evaluation was performed by means of microplate format for hydrocarbon degrading microorganisms using Acinetobacter sp. An inhibitory effect was observed in the recovering of cultivable cells when XTT concentrations increased from 0,5 mM to 2 mM. Incubation time favored this recovering. Detection limit of this technique was established at 10² UFC/ml. Production of the XTT-formazan was positively related with initial cell concentration and negatively with incubation time.
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Objecflve To evaluate the performance of two rapid and low-cost metheds(MTT test,and rosazurin mierotitre assay)for the detection of resistance to first-line drugs in Mycobacterium tuberculosis.Methods sixty-four Myeobaeterium tuberculosis clinical isohtes were tested by the MTT test and the rosazuxin microtitre assay(REMA)respectively,and the results were compared with those obtained with the absolute concentration method on L(o)wenstein Jensen medium.Results The MTT test and the resazurin microtitre assay showed a good agreement compared with the absolute concentration method for all first-line drugs tested.The sensitibity,specificity and accuracy of the MTT test were 94.8%,96.0%,95.3%,for RFP;93.8%,93.8%,93.8% for INH;92.9%,96.O%,95.3% for EMB,90.6%,87.5%,89.1% for SM,respectively.The sensitivity,specificity and accuracy of the resazurin microtitre assay were 92.3%,96.0%,93.8%,for RFP;90.6%,90.6%,90.6% for INH;92.9%,94.0%,93.8% for EMB,87.5%,87.5%,87.5% for SM,respectively.The Kappa value of the MTT test and the absolute concentration method for the detection of resistance to RFP,INH,EMB,SM were 0.857,0.831,0.714,0.792.respeedvely;The Kappa value of the regazurin mierotitre assay and the absolute concentration method for the detection of resistance to RFP,INH,EMB,SM were 0.871,0.826,0.826,0.750,respectively.The Kappa value of the MTT test and the resazurin microtitre assay for the detection of resistance to RFP,INH,EMB,SM wefe 0.889,0.875.0.787,0.844,respectively.Conclusions Both MTT test and the resazurin microtitre assays are simple,rapid,low-cost and sensitive for rapid detection of resistance to first-line drugs.They could be promising methods for susceptibility assay of the first-line antituberculosis drugs in low-resource countries.
ABSTRACT
It has been suggested that propofol has the protective effect on cerebral ischemia-reperfusion injury. The aim of this study is to evaluate the effect of propofol pretreatment on incomplete forebrain ischemia-reperfusion injury in rats. Thirty Sprague-Dawley rats were anesthetized with isoflurane in oxygen and randomly allocated into propofol group (n=13) and saline group (n=17). In propofol group, propofol was pretreated in a step-down scheme before inducing forebrain ischemia by occlusion of both common carotid arteries and arterial hypotension. After ischemia (20 min) and reperfusion (30 min), rats were decapitated. Brain was sliced to obtain coronal slices of 4-12 mm from frontal pole, which were reacted with 2% 2,3,5-triphenyl-2H-tetrazolium chloride (TTC) for 10 min to differentiate the damaged tissues from normal tissues. Median (interquartile range) values of the average percent infarct area were 0.0 (8.6)% and 20.1 (41.2)% in propofol and saline groups, respectively. There was significant difference between the groups. In conclusion, propofol may have a protective effect on incomplete forebrain ischemia-reperfusion injury.