Immunomodulatory activity in tumor-bearing mice treated with Withania somnifera extract

Abstract

We investigated some actions of Withania somnifera on the growth and differentiation of hematopoietic precursors [granulocyte/macrophage colony cell formation (CFU-GM)] of normal animals and EAT bearers, which were treated with different doses (20, 50, or 100 mg/kg/day). We also evaluated the presence of colony stimulatory factors in the animal's serum, as well as its survival. Furthermore, we analyzed lymphocyte proliferation, IFN-ɤ, and TNF-α concentrations in treated bearing mice. Our results demonstrated Withania somnifera effectiveness on hematopoietic precursors growth and differentiation in marrow and spleen TAE-bearing mice. As it was already expected, EAT produced myelosuppression and increased CFU-GM spleen number concomitantly. The treatment of EAT-bearing animals with W.S. (20, 50, and 100 mg/Kg) produced a dose-dependent increase in myelopoiesis, an increase in a lifetime, and a reduction in spleen colony number. All this happened parallel to survival. As to lymphocyte proliferation, they were also dose-dependent in treated bearing animals. Concerning IFN-γ levels, we observed a significant reduction in non-treated bearing mice. Levels of TNF-α of treated bearing mice significantly increased when compared to the non-treated bearing group. These results are encouraging since they favor the use of W.S. extract in therapeutic combinations with other chemotherapeutic agents to reduce myelotoxicity and supplement the tumoricidal efficacy of this plant.