Radiomitigative Effects of Grifola frondosa Preparations on Mice Exposed to Lethal Ionizing Irradiation
*Ikuo Kashiwakura Department Of Radiological Life Sciences, Hirosaki University Graduate School Of Health Sciences, Japan
*Corresponding Author: Ikuo Kashiwakura
Department Of Radiological Life Sciences, Hirosaki University Graduate School Of Health Sciences, Japan Email:email@example.com
Published on: 2018-02-26
Maitake mushroom Grifola frondosa (GF) is a polyporaceous fungus, increasingly recognized as a good source of polysaccharide compounds with dramatic health-promoting potential. To examine the radiomitigative effect of GF, we tested the effect of seven preparations of this fungus on the survival of mice exposed to lethal ionizing radiation. We tested freeze-dried fungal body of GF (YM-6A), α-glucans obtained from YM-6A (YM-2A), fiber components of GF (YM-11), GF mycelium (YM-51), hot-air dried ingredients (MD), 1:1 mixture of MD and YM-6A (YM-52), and crystal ergothioneine (YM-44). Each preparation was administered orally to 8-week-old mice for 7 consecutive days at 10 mg/kg/day before X-irradiation. All non-treated individuals died by day 16. The survival rate among the mice treated with YM-6A was 20% on day 30. One YM-52-treated mouse also survived until day 28. However, other preparations (YM-2A, YM-11, YM-44, and YM-51) had no radiomitigative effect. None of the substances used in the study affected the growth of non-irradiated control mice, demonstrating that these preparations were not toxic. We conclude that GF can be ingested with daily food and some of the preparations can counteract the harmful effects of radiation exposure, such as low-dose, long-term exposure.
Maitake mushroom, Grifola frondosa (GF), is a polyporaceous fungus, increasingly recognized as an excellent source of polysaccharide compounds with many health benefits. GF extracts have shown particular promise as immunomodulating agents and as adjuncts in cancer and HIV therapies. They may also provide some benefit in the treatment of hyperlipidemia, hypertension, and hepatitis. Ma et al. have suggested that GF increases glucose metabolism and synthesis of intracellular glycogen through the Akt/GSK-3 pathway. They have concluded that GF can be considered a potential source of the molecules with antidiabetic properties. Ionizing radiation with low-linear energy transfer, such as X-rays, produces reactive oxygen species by indirectly affecting the water molecules. Such irradiation also generates potentially lethal double-strand DNA breaks, triggering apoptosis or stress-related responses. Exposure to a lethal dose of ionizing radiation causes severe acute radiation syndrome (ARS) involving bone marrow and gastrointestinal tissue death. ARS is associated with a decrease in the peripheral blood cell count and gastrointestinal dysfunction, ultimately leading to death due to systemic bleeding