RESUMO
Drug-induced liver injury (DILI) has a considerable impact on human health and is a major challenge in drug safety assessments. DILI is a frequent cause of liver injury and a leading reason for post-approval drug regulatory actions. Considerable variations in the expression levels of both cytochrome P450 (CYP) and conjugating enzymes have been described in humans, which could be responsible for increased susceptibility to DILI in some individuals. We herein explored the feasibility of the combined use of HepG2 cells co-transduced with multiple adenoviruses that encode drug-metabolising enzymes, and a high-content screening assay to evaluate metabolism-dependent drug toxicity and to identify metabolic phenotypes with increased susceptibility to DILI. To this end, HepG2 cells with different expression levels of specific drug-metabolism enzymes (CYP1A2, CYP2B6, CYP2C9, CYP2C19, CYP2D6, CYP2E1, CYP3A4, GSTM1 and UGT2B7) were exposed to nine drugs with reported hepatotoxicity. A panel of pre-lethal mechanistic parameters (mitochondrial superoxide production, mitochondrial membrane potential, ROS production, intracellular calcium concentration, apoptotic nuclei) was used. Significant differences were observed according to the level of expression and/or the combination of several drug-metabolism enzymes in the cells created ad hoc according to the enzymes implicated in drug toxicity. Additionally, the main mechanisms implicated in the toxicity of the compounds were also determined showing also differences between the different types of cells employed. This screening tool allowed to mimic the variability in drug metabolism in the population and showed a highly efficient system for predicting human DILI, identifying the metabolic phenotypes associated with increased DILI risk, and indicating the mechanisms implicated in their toxicity.
Assuntos
Doença Hepática Induzida por Substâncias e Drogas/etiologia , Família 2 do Citocromo P450/genética , Avaliação Pré-Clínica de Medicamentos/métodos , Testes de Toxicidade/métodos , Adenoviridae/genética , Família 2 do Citocromo P450/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Ensaios de Triagem em Larga Escala/métodos , Humanos , Inativação Metabólica/genética , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismoRESUMO
A patented organotin di-n-butyl-di-(4-chlorobenzohydroxamato)tin (DBDCT) with high a antitumor activity was designed, however, its antitumor and toxic mechanisms have not yet been clearly illustrated. Hepatic proteins of DBDCT-treated rats were identified and analyzed using LC-MS/MS with label-free quantitative technology. In total, 149 differentially expressed proteins were successfully identified. Five protein and mRNA expressions were involved in the peroxisome proliferator-activated receptor (PPAR) signaling pathway, including a scavenger receptor (CD36), adipocyte fatty acid binding protein 4 (FABP4), enoyl-CoA hydratase (EHHADH), acetyl-CoA acyltransferase 1 (ACAA1), and phosphoenolpyruvate carboxykinase (PEPCK) in DBDCT-treated Rat Liver (BRL) cells. PPAR-α and PPAR-λ were also significantly decreased at both protein and mRNA levels. Furthermore, compared with the DBDCT treatment group, a special blocking agent of PPAR-λ T0070907 was used to evaluate the relationship between PPAR-λ and its downstream genes. Our studies indicated that DBDCT may serve as a modulator of PPAR-λ, further up-regulating CD36, FABP4 and EHHADH on the PPAR signal pathway.
Assuntos
Fígado/metabolismo , Fígado/patologia , Compostos Orgânicos de Estanho/toxicidade , PPAR alfa/metabolismo , Proteômica/métodos , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Antígenos CD36/metabolismo , Caspases/metabolismo , Linhagem Celular , Ativação Enzimática/efeitos dos fármacos , Proteínas de Ligação a Ácido Graxo/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Fígado/efeitos dos fármacos , Compostos Orgânicos de Estanho/química , PPAR alfa/genética , Enzima Bifuncional do Peroxissomo/genética , Enzima Bifuncional do Peroxissomo/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos WistarRESUMO
Isoniazid (INH) is an antituberculosis drug associated with idiosyncratic liver injury in susceptible patients. INH-induced hepatotoxicity remains a significant clinical problem, but the underlying mechanisms are still unclear, despite the growing evidence that INH and/or its major metabolite, hydrazine, play an important role in hepatotoxicity.
Assuntos
Antituberculosos/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Isoniazida/toxicidade , Antituberculosos/farmacocinética , Apoptose/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/enzimologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Sistema Enzimático do Citocromo P-450/metabolismo , Família 2 do Citocromo P450 , Humanos , Isoniazida/farmacocinética , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/patologia , Estresse Oxidativo/efeitos dos fármacosRESUMO
El fenómeno de la toxicidad hepática inducida por medicamentos cobró relevancia hace algunos años con el estudio de las reacciones adversas a medicamentos. El daño producido en el hígado por un xenobiótico que altera su función es lo que se conoce como toxicidad hepática. La importancia de reconocer y diagnosticar la toxicidad hepática por medicamentos estriba en su gravedad potencial; no en vano es la causa más frecuente por la que la industria farmacéutica retira medicamentos. La tuberculosis es una pandemia que afecta a gran parte de la población mundial y junto con el VIH es una enfermedad cada vez más frecuente en Colombia. Esta enfermedad se puede considerar como una situación especial porque para su tratamiento es preciso suministrar, por largos períodos, medicamentos con potencial tóxico para el hígado.El objetivo de este artículo es revisar algunos aspectos relacionados con la toxicidad hepática secundaria a medicamentos antituberculosos, tales como: epidemiología, factores de riesgo, mecanismos de toxicidad, manifestaciones clínicas, diagnóstico, tratamiento y seguimiento.
Hepatotoxicity is the alteration of liver structure and function induced by either drugs or other substances. The importance of its proper diagnosisrests on its potential severity. It is the most frequent reason by which the pharmaceutical industry withdraws its products. Tuberculosis is a pandemicinfection affecting a large proportion of the world population. Together with HIV infection it is becoming ever more frequent in Colombia. Tuberculosisposes a special challenge because itstreatment requires the administration, during long periods, of drugs with the potential of inducing liver injury. In this article some aspects of hepatotoxicity induced by antituberculosis drugs are reviewed, namely: epidemiology, risk factors, mechanisms, clinical manifestations, diagnosis, treatment and follow-up.
