Chlorella vulgaris restores bone marrow cellularity and cytokine production in lead-exposed mice

Chlorella vulgaris (CV) was examined for its modulating effects on the reduction induced by lead (Pb) on the numbers of marrow hematopoietic stem cells (HSCs) (c-Kit(+)Lin(-)), granulocyte-macrophage progenitors (Gr1(+)Mac1(+)) and total bone marrow cellularity. In mice gavage-treated daily with 50 mg/kg dose of CV for 10 days, concomitant to a continuous offering of 1300 ppm lead acetate in drinking water, the treatment with the algae recovered the significantly reduced numbers of these cell populations to control values. As CV may have a myelostimulating effect through the induction of cytokines, we evaluated its modulating effects on the production of IL-1 alpha, TNF-alpha, IFN-gamma, IL-10 and IL-6. Our results demonstrated that lead significantly impairs the production of IFN-gamma, IL-1 alpha and TNF-alpha and increases the production of IL-10 and IL-6 and that these effects are successfully modulated by the CV treatment. The activity of NK cells, reduced in Pb-exposed animals, was raised to levels higher than those of controls in the exposed group treated with CV. Treatment with the algae also stimulated the production of IFN-gamma, IL-1 alpha, TNF-alpha and NK cells activity in normal mice. In addition, zinc bone concentrations, reduced in lead-exposed mice, were partially, but significantly, reversed by the treatment with CV. (C) 2011 Elsevier Ltd. All rights reserved.49112934294