Immunoenhancing Effects ofEuglena gracilison a Cyclophosphamide-Induced Immunosuppressive Mouse Model

Abstract

In this study, the effects of the immune stimulator Euglena gracilis (Euglena) in cyclophosphamide (CCP)-induced immunocompromised mice were assessed. The key component β-1,3-glucan (paramylon) constitutes 50% of E. gracilis. Mice were orally administered Euglena powder (250 and 500 mg/kg body weight (B.W.)) or β-glucan powder (250 mg/kg B.W.) for 19 days. In a preliminary immunology experiment, ICR mice were intraperitoneally injected with 80 mg of CCP/kg B.W. during the final 3 consecutive days. In the main experiment, BALB/c mice were treated with CCP for the final 5 days. To evaluate the enhancing effects of Euglena on the immune system, mouse B.W., the spleen index, natural killer (NK) cell activity and mRNA expression in splenocytes lungs and livers were determined. To detect cytokine and receptor expression, splenocytes were treated with 5 μg/ml concanavalin A or 1 μg/ml lipopolysaccharide. The B.W. and spleen index were significantly increased and NK cell activity was slightly enhanced in all the experimental groups compared to the CCP-only group. In splenocytes, the gene expression levels of tumor necrosis factor-α, interferon-γ, interleukin (IL)-10, IL-6, and IL-12 receptor were increased in the E. gracilis and β-glucan groups compared to the CCP-only group, but there was no significant difference. Treatment with 500 mg of Euglena/kg B.W. significantly upregulated dectin-1 mRNA expression in the lung and liver compared to the CCP-only group. These results suggest that Euglena may enhance the immune system by strengthening innate immunity through immunosuppression.

Evaluation of the Effects of Euglena gracilis on Enhancing Immune Responses in RAW264.7 Cells and a Cyclophosphamide-Induced Mouse Model

“…These results show that Euglena might affect the immune response by T-cell-related cytokine expression in splenocytes and confirm its effect on the immune response in macrophage cells. Thus, in this study we sought to provide evidence supporting the immune-enhancing effect described in a previous study [ 38 ]. However, the detailed mechanisms underlying the immune response, including signaling pathways and T-cell mediation, have not been clearly elucidated.…”

“…A previous study demonstrated that Euglena enhances dectin-1 expression, which promotes innate immunity and induces inflammatory cytokine expression in lymphocytes [ 38 ]. These results show that Euglena might affect the immune response by T-cell-related cytokine expression in splenocytes and confirm its effect on the immune response in macrophage cells.…”

Unveiling Immunomodulatory Effects of Euglena gracilis in Immunosuppressed Mice: Transcriptome and Pathway Analysis

“…Euglena and β-glucan have been shown to improve health by enhancing immunity, inhibiting atopic dermatitis, and modulating gut microbial composition [ 6 , 7 ]. In vitro, in vivo, and clinical trial studies have demonstrated that Euglena and β-glucan activate the immune system by releasing cytokines and inducing the immune cells such as natural killer cells or T lymphocytes [ 8 - 10 ]. They also activate the production of TNF-alpha in macrophages and modulate the expression of various cytokines [ 10 ].…”