Dieckol rescues mice from lethal irradiation by accelerating hemopoiesis and curtailing immunosuppression.
OBJECTIVE
To evaluate the radioprotective effect of dieckol, a component of the brown algae Ecklonia cava.


METHODS
Mice were lethally irradiated, treated with dieckol and surveyed for survival and the mechanism of radioprotection.


RESULTS
Dieckol treatment lengthened the survival of irradiated mice and significantly accelerated the hemopoietic recovery of bone marrow cells and peripheral immune cells compared with irradiated, but untreated controls. Dieckol also enhanced the proliferation and differentiation of immune cells, which had been suppressed by ionising radiation. It turned out that the increased expression of oxygen radical-scavenging enzyme manganese superoxide dismutase (MnSOD) and subsequent reduction in DNA damage and lipid peroxidation was crucial for dieckol's radioprotective effect. In addition, the dieckol-induced modulation of protein 53 (p53)-dependent pathways further strengthened the radioresistance of immune cells.


CONCLUSIONS
Dieckol can be a promising agent for reducing the time needed for reconstitution of hemopoietic cells after exposure to irradiation.
Park
Eunjin
E
Jeju National University, South Korea.
Ahn
Ginnae
G
Yun
Jin-Suk
JS
Kim
Min Ju
MJ
Bing
So Jin
SJ
Kim
Dae Seung
DS
Lee
Jehee
J
Lee
Nam Ho
NH
Park
Jae Woo
JW
Jee
Youngheun
Y
D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D001572:Benzofurans / Q000494:pharmacology*; D049109:Cell Proliferation / Q000187:drug effects; D004249:DNA Damage; D016166:Free Radical Scavengers / Q000378:metabolism; D005720:Gamma Rays; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000378:metabolism; D006410:Hematopoiesis / Q000187:drug effects* / Q000528:radiation effects; D007108:Immune Tolerance / Q000187:drug effects* / Q000528:radiation effects; D007165:Immunosuppression Therapy; D007700:Kinetics; D015227:Lipid Peroxidation / Q000187:drug effects; D051379:Mice; D011837:Radiation-Protective Agents / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D013154:Spleen / Q000166:cytology / Q000187:drug effects; D016019:Survival Analysis; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism
D001572:Benzofurans; D016166:Free Radical Scavengers; D011837:Radiation-Protective Agents; D017382:Reactive Oxygen Species; D016159:Tumor Suppressor Protein p53; C503840:dieckol; D016178:Granulocyte-Macrophage Colony-Stimulating Factor