ISBN: 978-83-60043-10-3 - eurobic9

Eurobic9, 2-6 September, 2008, Wrocław, Poland
P31. Effects of Mannitol or Erythritol on Human Bronchial Epithelial Cells
Treated with Chromium(VI)
A. Costa a , V. Moreno a , M. Prieto b , C. Alpoim c
a
Inorganic Chemistry, University of Barcelona, Marti i Franquès 1-11, 08028, Barcelona, Spain
e-mail: andrenunocosta@gmail.com
b
Microbiology, University of Barcelona, Diagonal 645, 08028, Barcelona, Spain
c
Biochemistry, University of Coimbra, Box 3126, 3001-401, Coimbra, Portugal
Toxicity of Cr(VI) and its carcinogenic effects have been extensively studied[1]. Attempts of minimizing these
biological consequences have led to many researches to study the mechanisms of action inside the cell[2].
Here, we present results on the behaviour of Cr(VI) in presence or absence of mannitol and erythritol on human
bronchial epithelial cells. The evolution of solutions of Cr(VI), Cr(VI) with ascorbate anion, Cr(VI) with
mannitol or erythritol and Cr(VI) with ascorbate anion and mannitol or erythritol, at room T, pH= 7.4, was
followed by UV-visible spectroscopy. The presence of Cr(V) intermediate product of reduction of Cr(VI) by
mannitol, was detected by EPR spectroscopy. A typical sharp signal centered at g= 1.98, showing a
superhyperfine splitting, 1 H aiso = 1,022 x 10 -4 cm -1 , corresponding to the coupling of four protons from two
mannitol molecules coordinated to the metal ion was observed. In the EPR spectrum, four broad signals due to
hyperfine coupling with 53 Cr nucleus (I = 3/2), Aiso = 17.75 x 10 -4 cm -1 , were also detected. AFM images of the
human bronchial epithelial cells treated with Cr(VI) and Cr(VI)/alditol solutions were obtained. The cells were
cultured on polymer cover slips coated with gelatine type B and treated with the corresponding solution.
Samples were fixed with glutaraldehyde prior to visualization in air. The images obtained allowed us to observe
the morphology of the cells surface and the integrity of the membrane.
References:
[1] IARC (1990) Monographs on the evaluation of carcinogenic risks to humans, Chromium, Nickel and
Welding, Vol. 49, World Health Organization, Lyon, pp. 49-256.
[2] B.D. Martin, J.A. Schoenhard, J.M. Hwang, K.D. Sugden, Mutation Research, 610, 74 (2006)
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