Abstract
Based on the well-known toxicity of cyclophosphamide (CYP) on the immune system, this research investigated the modulating effects of the long-term dietary Chlorella vulgaris (CV) supplementation on the immunosuppression induced by CYP in mice, in order to provide a novel dietary design to mitigate the side effects of CYP therapy. Control, CYP-treated, CYP + CV (6%), CYP + CV (12%) and CYP + CV (24%) were used for 6 weeks, CV supplement in diet recovered the significantly reduced immunological function in CYP treated mice. As CV may have a modulating function through the inducible expression of cytokines, we assayed the expressions of interleukin-2 (IL-2), interleukin-12 (IL-12), tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ). Our results suggested that CYP significantly reduced the lymphocytes proliferation and phagocytic activities of macrophages, and stimulated the production of IL-2, IL-12, TNF-α and IFN-γ and that this impairment has been successfully adjusted by CV supplementation. Treatment with the algae also enhanced the natural killer (NK) cells cytotoxicity, and ameliorate histological changes of the spleen in CYP-treated mice. Therefore, as we found in this study, a diet supplemented with whole CV has beneficial effects on CVP-induced immunosuppression, through its immunomodulatory potential.