RESUMO
Erythropoietic protoporphyria (EPP) is a disease associated with ferrochelatase deficiency and characterized by the accumulation of protoporphyrin IX (PROTO IX) in erythrocytes, liver, and skin. In some cases, a severe hepatic failure and cholestasis were observed. Griseofulvin (Gris) develops an experimental EPP with hepatic manifestations in mice such as PROTO IX accumulation followed by cellular damage as wells as necrotic and inflammatory processes. The antioxidant defense system was also altered. The aim was to evaluate the possible protective effect of different antioxidant compounds: trolox (Tx), ascorbic acid (Asc), the combination Tx and Asc, melatonin (Mel), and the polyphenols: ellagic acid, quercetin, chlorogenic acid, caffeic acid, gallic acid, and ferulic acid on liver damage and oxidative stress markers in a mouse model of EPP. Coadministration of Gris with Tx, Asc, and its combination, or Mel mainly affected heme biosynthetic pathway, resulting in a decrease in ALA-S activity which was increased by Gris, while the tested polyphenols exerted a protective effect on oxidative stress, decreasing lipid peroxidation and the activity of some antioxidant enzymes. In conclusion, antioxidant compounds can only protect partially against the liver damage induced by Gris, reducing oxidative stress or acting on heme regulation.
Assuntos
Antifúngicos/efeitos adversos , Antioxidantes/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Griseofulvina/efeitos adversos , Animais , Antioxidantes/administração & dosagem , Biomarcadores/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Modelos Animais de Doenças , Glutationa/metabolismo , Heme/metabolismo , Masculino , Camundongos , Superóxido Dismutase/metabolismoRESUMO
Erythropoietic Protoporphyria (EPP) is a disease associated with ferrochelatase deficiency, which produces accumulation of protoporphyrin IX (PROTO IX) in erythrocytes, liver and skin. In some cases, a severe hepatic failure and cholestasis was observed. Griseofulvin (Gris) develops an experimental EPP with hepatic manifestations in animals. The aim of this work was to further characterize this model studying its effect on different metabolisms in mice Gris feeding (0-2.5%, 7 and 14 days). PROTO IX accumulation in liver, blood and feces, induction of ALA-S activity, and a low rate of Holo/Apo tryptophan pyrrolase activity was produced, indicating a reduction of free heme pool. The progressive liver injury was reflected by the aspect and the enlargement of liver and the induction of hepatic damage. Liver redox balance was altered due to porphyrin high concentrations; as a consequence, the antioxidant defense system was disrupted. Heme oxygenase was also induced, however, at higher concentrations of antifungal, the free heme pool would be so depleted that this enzyme would not be necessary. In conclusion, our model of Protoporphyria produced liver alterations similar to those found in EPP patients.
Assuntos
Antifúngicos/toxicidade , Griseofulvina/toxicidade , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Hidrocarboneto de Aril Hidroxilases/metabolismo , Citocromo P-450 CYP2A6 , Citocromo P-450 CYP3A/metabolismo , Modelos Animais de Doenças , Heme/metabolismo , Heme Oxigenase (Desciclizante)/metabolismo , Imuno-Histoquímica , Fígado/patologia , Masculino , Camundongos , Protoporfiria Eritropoética/induzido quimicamente , Protoporfirinas/metabolismo , Triptofano Oxigenase/metabolismoRESUMO
Several drugs and stress are involved in the triggering of attacks in acute porphyrias. The central nervous system is extremely sensitive to free radical damage because of a relatively low antioxidant capacity. We have demonstrated that mice brain cholinergic system was altered by the effect of some porphyrinogenic agents. The aim of this work was to investigate how known porphyrinogenic drugs affect delta-Aminolevulinic acid synthetase (ALA-S), which is the response of heme oxygenase (HO) to this challenge and to evaluate if the xenobiotics studied develop stress oxidative in mice brain. HO activity was 50-70% induced after chronic Enflurane and Isoflurane anaesthesia, dietary Griseofulvin and starvation. An increase in mRNA HO expression was caused by chronic anaesthesia and Veronal treatments; instead allylisopropilacetamide (AIA) reduced mRNA expression. ALA-S activity was induced by acute administration of anaesthetics (89%), veronal (240%) and ethanol (80%), while ALA-S mRNA expression augmented by chronic administration of enflurane, AIA and veronal. Stress markers such as superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase activities and malondialdehyde and reduced glutathione levels showed different responses depending on the xenobiotic assayed. In conclusion, some of the drugs studied produced oxidative stress in brain that was confirmed through HO induction and this could be one of the factors leading to porphyric neuropathy.