Mitigation of the hematopoietic and gastrointestinal acute radiation syndrome by octadecenyl thiophosphate, a small molecule mimic of lysophosphatidic acid.
Radiat Res
; 183(4): 465-75, 2015 Apr.
Article
em En
| MEDLINE
| ID: mdl-25807318
ABSTRACT
We have previously demonstrated that the small molecule octadecenyl thiophosphate (OTP), a synthetic mimic of the growth factor-like mediator lysophosphatidic acid (LPA), showed radioprotective activity in a mouse model of total-body irradiation (TBI) when given orally or intraperitoneally 30 min before exposure to 9 Gy γ radiation. In the current study, we evaluated the effects of OTP, delivered subcutaneously, for radioprotection or radiomitigation from -24 h before to up to +72 h postirradiation using a mouse TBI model with therapeutic doses at around 1 mg/kg. OTP was injected at 10 mg/kg without observable toxic side effects in mice, providing a comfortable safety margin. Treatment of C57BL/6 mice with a single dose of OTP over the time period from -12 h before to +26 h after a lethal dose of TBI reduced mortality by 50%. When administered at +48 h to +72 h postirradiation (LD50/30 to LD100/30), OTP reduced mortality by ≥34%. OTP administered at +24 h postirradiation significantly elevated peripheral white blood cell and platelet counts, increased crypt survival in the jejunum, enhanced intestinal glucose absorption and reduced endotoxin seepage into the blood. In the 6.4-8.6 Gy TBI range using LD50/10 as the end point, OTP yielded a dose modification factor of 1.2. The current data indicate that OTP is a potent radioprotector and radiomitigator ameliorating the mortality and tissue injury of acute hematopoietic as well as acute gastrointestinal radiation syndrome.
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Base de dados:
MEDLINE
Assunto principal:
Compostos Organofosforados
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Lisofosfolipídeos
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Trato Gastrointestinal
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Síndrome Aguda da Radiação
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Hematopoese
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article