Efficacy of Spirulina platensis on immune functions in cancer mice with systemic candidiasis

The aim of this study was to investigate the immunomodulatory effects of Spirulina platensis (S. platensis) by measuring the levels of serum interleukin (IL)-4, IL-10, IL-17, tumor necrosis factor (TNF)-α and interferon (IFN)-|γ| in mice suffered from systemic candidiasis and breast cancer. The aqueous extract of S. platensis was selected for this study. Balb/C female mice were inoculated with Candida albicans (C. albicans) and spontaneous mouse mammary tumor (SMMT). Five days after Candida inoculation, the serum levels of tissue inhibitor of metalloproteinase-1 (TIMP-1) were assessed by Enzyme- linked immunosorbent assay (ELISA). The animals were treated daily with S. platensis solution (800 mg/kg, 0.2 ml, orally) for 3 days before IV challenge with C. albicans, and SC challenge with SMMT and continued for 10 days. The survival rate and tumor size of understudy animals were determined, as well. ELISA determined the levels of TNF-α, IFN-γ IFN T γ-4, IL-10 and IL-17 cytokines in supernatants. The results demonstrated that S. platensis decreased the secretion of IL-4 (45.1 pg/ml) and IL-10 (208.4 pg/ml) in tumor-bearing mice infected with C. albicans, whereas the levels of IL-17, TNF-α and IFN-γ increased to nearly 93.4 p/ml, 316.2 pg/ml and 137.1 pg/ml in this group, respectively. These findings clearly suggest that S. platensis has a remarkable immunomodulatory effect, which provides a scientific validation for the popular use of this natural substance, and assisted in the additional investigation of their complete mechanism of action.