J Vet Sci. 2008 Sep;9(3):281-284   
 

The radioprotective effects of the hexane and ethyl acetate extracts of Callophyllis japonica in mice that undergo whole body irradiation

Jeongtae Kim1, Changjong Moon6, Heechul Kim1, Jinwoo Jeong1, Juyeon Lee1, Jihoon Kim1, Jin Won Hyun2,3, Jae Woo Park2,4, Mi Yeon Moon5, Nam Ho Lee2,5, Sung Ho Kim6, Youngheun Jee1,2,3, Taekyun Shin1,2,3,*
 

1College of Veterinary Medicine, and the Research Institute for Subtropical Agriculture and Biotechnology, 2Applied Radiological Science Research Institute, 3Department of Biochemistry, College of Medicine, 4Department of Nuclear and Energy Engineering, College of Engineering, 5Department of Chemistry, College of Natural Science, Cheju National University, Jeju 690-756, Korea
6Department of Veterinary Anatomy, College of Veterinary Medicine, Chonnam National University, Gwangju 500-757, Korea
* shint@cheju.ac.kr
 

The radioprotective activity of extracts from the red seaweed Callophyllis (C.) japonica was investigated in mice that underwent whole-body exposure to gamma radiation. A methanol extract of C. japonica and its fractions [hexane, ethyl acetate (EtOAc), butanol and the remaining H2O] were used. Each fraction (100 mg/kg body weight) was administered intraperitoneally (i.p.) 2 times into the BALB/c mice, once at 1 and once at 24 h before exposure to 9 Gray (Gy) of gamma radiation. Pre-irradiation administration of the hexane and EtOAc fractions saved the mice, with their survival rates being greater than 80% at 30 days post-irradiation; the mice that were pretreated with the other fractions showed survival rates lower than 20% over the same time period. To examine the effect of each C. japonica fraction on the survival of intestinal and bone marrow stem cells, the number of intestinal crypts and bone marrow cells in the gamma-irradiated mice were examined. Pre-treatment of mice (i.p., 100 mg/kg body weight at 1 and 24 h before irradiation) with the hexane or EtOAc fraction prior to 6-Gy irradiation significantly protected the number of jejunal crypts and bone marrow cells at 9 days after irradiation. These findings suggest that certain extracts from C. japonica, when they are administered prior to irradiation, play an important role in the survival of irradiated mice, and this is possibly due to the extracts protecting the hematopoietic cells and intestinal stem cells against gamma irradiation.