Evaluation of Phellinus linteus mycelium extract on protection against radiation damage in mice.

• Main Authors: Shu-Ming Huang, 黃淑敏
• Other Authors: Miao-Lin Hu
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/15860019604072613651

博士 === 國立中興大學 === 食品暨應用生物科技學系所 === 104 === Radiation exposure is one of the potential carcinogenic factors in our living environment. The hematopoietic system damage is the main side effect of radiation exposure. Phellinus linteus (PL), one of the medicinal fungus in East Asia, has been shown to exhibit anti-cancer, anti-inflammatory and immunomodulative effects. However, it is unclear whether PL protects against radiation exposure. This study aimed to investigate the protective effects of PL extracts (PLE) against radiation damage in mice. This study was divided into four phases. First, the mice were irradiated once with different doses (4, 5, 6, and 8 Gy), and the survival rate was observed within 30 d. Results revealed that the survival rate of each groups were 100%, 100%, 13%, and 0%. Second, mice were irradiated once with 6 Gy to evaluate the radioprotective potential of five botanical extracts, including Antrodia cinnamomea (AC), Cordyceps militaris (CM), PL,Rhodiola rosea (RR), and Agaricus blazei Murrill (AM). Results showed that the survival rates were 34% in radiation control group, 60% in PL and RR group, 54% in CM group, and 40% in AC and AM groups. Third, mice were irradiated with 4 Gy once per week for three consecutive weeks and/or orally given PLE (1.5 g/kg) daily for 2 weeks before irradiation to evaluate the survival rate. Results revealed that survival rate in 4 Gy group and PLE group were 12.5% and 62.5%, respectively. We found that the levels of WBC and the amounts of hemoglobin and platelets in radiation group were significant lower than those of control group. PLE supplementation, especially at 1.5 g/kg, effectively restored radiation-induced abnormal parameters, including the levels of WBC and the amounts of hemoglobin and platelets. Finally, we determined the protective effect of PL polysaccharide (PLP) on low dose of irradiated mice. Mice were irradiated with 2 Gy once per week and/or orally given PLP (100 and 500 mg/kg) daily for four consecutive weeks. Results revealed that PLP administration, especially at high dose, significantly restored radiation-induced loss of WBC and platelets. In addition, PLP supplementation significantly ameliorated radiation-induced femur fibrosis. Similarly, PLP effectively reversed radiation-induced abnormal serum levels of immunological parameters, including IgG, IgG1 and IgG2, and activities of antioxidant enzymes, such as SOD, catalase and GSH peroxidase. Overall, this dissertation research demonstrated that PLE and PLP effectively protected against radiation damage by increasing antioxidant activities and ameliorating abnormal hematopoietic and immunological systems in mice.