Radioprotective effects of ginsan, an immunomodulator.
We previously reported that ginsan, a purified polysaccharide isolated from Panax ginseng, had a mitogenic activity, induced LAK cells, and increased levels of several cytokines. In an effort to identify other immunostimulatory effects, we evaluated the protective effects of ginsan injected in vivo against radiation by measuring its effects on the CFU-S bone marrow cells and spleen cells. Ginsan was found to significantly increase the number of bone marrow cells, spleen cells, granulocyte-macrophage colony-forming cells (GM-CFC), and circulating neutrophils, lymphocytes and platelets in irradiated mice. In addition, ginsan induced the endogenous production of cytokines such as Il1, Il6, Ifng and Il12, which are required for hematopoietic recovery, and was able to enhance Th1 function while interfering with the Th2 response in irradiated mice. We demonstrated that pretreatment with ginsan protected mice from the lethal effects of ionizing radiation more effectively than when it was given immediately after or at various times after irradiation. A significant increase in the LD(50/30) from 7.54 Gy for PBS injection to 10.93 Gy for mice pretreated with 100 mg/kg ginsan was observed. These findings indicate that ginsan may be a useful agent to reduce the time necessary for reconstituting hematopoietic cells after irradiation.
Song
Jie-Young
JY
Laboratory of Immunology, Korea Institute of Radiological and Medical Sciences, KAERI, 215-4, Gongneung dong, Nowon-ku, Seoul, 139-706, Korea.
Han
Seon-Kyu
SK
Bae
Kang-Gyu
KG
Lim
Dae-Seog
DS
Son
Soo-Jung
SJ
Jung
In-Sung
IS
Yi
Seh-Yoon
SY
Yun
Yeon-Sook
YS
D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000818:Animals; D001853:Bone Marrow / Q000187:drug effects / Q000528:radiation effects; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D016207:Cytokines / Q000235:genetics; D005260:Female; D005720:Gamma Rays; D006410:Hematopoiesis / Q000187:drug effects / Q000528:radiation effects; D006412:Hematopoietic Stem Cells / Q000187:drug effects / Q000528:radiation effects; D051379:Mice; D008807:Mice, Inbred BALB C; D011134:Polysaccharides / Q000494:pharmacology*; D012333:RNA, Messenger / Q000032:analysis; D011837:Radiation-Protective Agents / Q000494:pharmacology*; D013154:Spleen / Q000187:drug effects / Q000528:radiation effects
D000276:Adjuvants, Immunologic; D016207:Cytokines; D011134:Polysaccharides; D012333:RNA, Messenger; D011837:Radiation-Protective Agents; C111520:ginsan