Journal of Microbiology and Biotechnology

The Korean Society for Microbiology and Biotechnology (한국미생물·생명공학회)
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Immunoenhancing Effects of Euglena gracilis on a Cyclophosphamide-Induced Immunosuppressive Mouse Model

  • Yang, Hyeonji (Department of Food Science and Technology, Seoul National University of Science and Technology) ;
  • Choi, Kwanyong (Department of Food Science and Technology, Seoul National University of Science and Technology) ;
  • Kim, Kyeong Jin (Department of Nano Bio Engineering, Seoul National University of Science and Technology) ;
  • Park, Soo-yeon (Lab of Nanobio, Seoul National University of Science and Technology) ;
  • Jeon, Jin-Young (BIO R&D center, Daesang Corp.) ;
  • Kim, Byung-Gon (BIO R&D center, Daesang Corp.) ;
  • Kim, Ji Yeon (Department of Food Science and Technology, Seoul National University of Science and Technology)
  • Received : 2021.12.20
  • Accepted : 2021.12.27
  • Published : 2022.02.28
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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 ㎍/ml concanavalin A or 1 ㎍/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.

Keywords

Acknowledgement

This research was a part of a project titled 'Development of functional food material derived from marine resources, microalgae Euglena gracilis', funded by the Ministry of Oceans and Fisheries, Korea.

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