Effect of hemin on growth, protein content and the antioxidant defense system in Trypanosoma cruzi.

CICCARELLI, ALEJANDRA; ARAUJO, LIDIA; BATLLE, ALCIRA; LOMBARDO, MARIA ELISA

PARASITOLOGY

Cambridge University Press

Año: 2007 vol. 134 p. 959 - 965

0031-1820

A nutritional characteristic of trypanosomatid protozoa is that in vitro they need a heme compound as a growth factor, which is supplied as hemoglobin, hematin or hemin. Because hemin and related porphyrins are an important source of oxidative stress in biological systems, the effect of hemin on growth, protein content and the antioxidant defense system in compound as a growth factor, which is supplied as hemoglobin, hematin or hemin. Because hemin and related porphyrins are an important source of oxidative stress in biological systems, the effect of hemin on growth, protein content and the antioxidant defense system in compound as a growth factor, which is supplied as hemoglobin, hematin or hemin. Because hemin and related porphyrins are an important source of oxidative stress in biological systems, the effect of hemin on growth, protein content and the antioxidant defense system in compound as a growth factor, which is supplied as hemoglobin, hematin or hemin. Because hemin and related porphyrins are an important source of oxidative stress in biological systems, the effect of hemin on growth, protein content and the antioxidant defense system in in vitro they need a heme compound as a growth factor, which is supplied as hemoglobin, hematin or hemin. Because hemin and related porphyrins are an important source of oxidative stress in biological systems, the effect of hemin on growth, protein content and the antioxidant defense system in Trypanosoma cruzi was evaluated. We have observed that, in epimastigotes grown under different hemin concentrations in the culture medium (0-30 mg/l), 5 mg/l was the hemin concentration yielding optimum growth, above 15 mg/l there was a clear decrease in growth rate, producing the epimastigote to amastigote transformation. Such morphological change was observed together with a marked injury of the enzymatic machinery of the parasite, leading to diminished protein synthesis as well as lower activity of the antioxidant enzymes (superoxide dismutase, ascorbate peroxidase and trypanothione reductase), reduced total thiol content and a marked increase in the HemOx-1 activity and expression. The current work demonstrates that there is a correlation between higher hemin concentrations in the culture medium and oxidative damage in the cells. Under these conditions induction of HemOx-1 would indicate the important role of this enzyme as an antioxidant defense response in Trypanosoma cruzi. We have observed that, in epimastigotes grown under different hemin concentrations in the culture medium (0-30 mg/l), 5 mg/l was the hemin concentration yielding optimum growth, above 15 mg/l there was a clear decrease in growth rate, producing the epimastigote to amastigote transformation. Such morphological change was observed together with a marked injury of the enzymatic machinery of the parasite, leading to diminished protein synthesis as well as lower activity of the antioxidant enzymes (superoxide dismutase, ascorbate peroxidase and trypanothione reductase), reduced total thiol content and a marked increase in the HemOx-1 activity and expression. The current work demonstrates that there is a correlation between higher hemin concentrations in the culture medium and oxidative damage in the cells. Under these conditions induction of HemOx-1 would indicate the important role of this enzyme as an antioxidant defense response in Trypanosoma cruzi. We have observed that, in epimastigotes grown under different hemin concentrations in the culture medium (0-30 mg/l), 5 mg/l was the hemin concentration yielding optimum growth, above 15 mg/l there was a clear decrease in growth rate, producing the epimastigote to amastigote transformation. Such morphological change was observed together with a marked injury of the enzymatic machinery of the parasite, leading to diminished protein synthesis as well as lower activity of the antioxidant enzymes (superoxide dismutase, ascorbate peroxidase and trypanothione reductase), reduced total thiol content and a marked increase in the HemOx-1 activity and expression. The current work demonstrates that there is a correlation between higher hemin concentrations in the culture medium and oxidative damage in the cells. Under these conditions induction of HemOx-1 would indicate the important role of this enzyme as an antioxidant defense response in Trypanosoma cruzi. We have observed that, in epimastigotes grown under different hemin concentrations in the culture medium (0-30 mg/l), 5 mg/l was the hemin concentration yielding optimum growth, above 15 mg/l there was a clear decrease in growth rate, producing the epimastigote to amastigote transformation. Such morphological change was observed together with a marked injury of the enzymatic machinery of the parasite, leading to diminished protein synthesis as well as lower activity of the antioxidant enzymes (superoxide dismutase, ascorbate peroxidase and trypanothione reductase), reduced total thiol content and a marked increase in the HemOx-1 activity and expression. The current work demonstrates that there is a correlation between higher hemin concentrations in the culture medium and oxidative damage in the cells. Under these conditions induction of HemOx-1 would indicate the important role of this enzyme as an antioxidant defense response in Trypanosoma cruzi. was evaluated. We have observed that, in epimastigotes grown under different hemin concentrations in the culture medium (0-30 mg/l), 5 mg/l was the hemin concentration yielding optimum growth, above 15 mg/l there was a clear decrease in growth rate, producing the epimastigote to amastigote transformation. Such morphological change was observed together with a marked injury of the enzymatic machinery of the parasite, leading to diminished protein synthesis as well as lower activity of the antioxidant enzymes (superoxide dismutase, ascorbate peroxidase and trypanothione reductase), reduced total thiol content and a marked increase in the HemOx-1 activity and expression. The current work demonstrates that there is a correlation between higher hemin concentrations in the culture medium and oxidative damage in the cells. Under these conditions induction of HemOx-1 would indicate the important role of this enzyme as an antioxidant defense response in Trypanosoma cruzi.Trypanosoma cruzi.