Artigo Produção Nacional Revisado por pares

Cytoprotective effects of ascorbic acid on the ischemia-reperfusion injury of rat liver

2004; Elsevier BV; Volume: 36; Issue: 2 Linguagem: Inglês

10.1016/j.transproceed.2004.01.096

ISSN

1873-2623

Autores

Murched Omar Taha, H.S Souza, César Alexandre Fabrega Carvalho, Djalma José Fagundes, Manuel de Jesus Simões, Neil Ferreira Novo, Afonso Caricati‐Neto,

Tópico(s)

Mitochondrial Function and Pathology

Resumo

Fibroblast growth factor receptor 1 (Fgfr1) gene knockout impairs cardiomyocyte differentiation in murine embryonic stem cells (mESC). Here, various chemical compounds able to enhance cardiomyocyte differentiation in mESC [including dimethylsulfoxide, ascorbic acid (vitC), free radicals and reactive oxygen species] were tested for their ability to rescue the cardiomyogenic potential of Fgfr1−/− mESC. Among them, only the reduced form of vitC, l-ascorbic acid, was able to recover beating cell differentiation in Fgfr1−/− mESC. The appearance of contracting cells was paralleled by the expression of early and late cardiac gene markers, thus suggesting their identity as cardiomyocytes. In the attempt to elucidate the mechanism of action of vitC on Fgfr1−/− mESC, we analyzed several parameters related to the intracellular redox state, such as reactive oxygen species content, Nox4 expression, and superoxide dismutase activity. The results did not show any relationship between the antioxidant capacity of vitC and cardiomyocyte differentiation in Fgfr1−/− mESC. No correlation was found also for the ability of vitC to modulate the expression of pluripotency genes. Then, we tested the hypothesis that vitC was acting as a prolyl hydroxylase cofactor by maintaining iron in a reduced state. We first analyze hypoxia inducible factor (HIF)-1α mRNA and protein levels that were found to be slightly upregulated in Fgfr1−/− cells. We treated mESC with Fe2 + or the HIF inhibitor CAY10585 during the first phases of the differentiation process and, similar to vitC, the two compounds were able to rescue cardiomyocyte formation in Fgfr1−/− mESC, thus implicating HIF-1α modulation in Fgfr1-dependent cardiomyogenesis.

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