MedElevator
Войти в исследования International journal of radiation biology · 1999
Effects of intracellular calcium chelator BAPTA-AM on radiation-induced apoptosis regulated by activation of SAPK/JNK and caspase-3 in MOLT-4 cells.
СтатьяПоддержка исследования: вне правительства СШАНазвание и аннотация: Перевод в очереди
Обработка статьи · этапы, ошибки и управление
Загрузка состояния…
Ошибки и ограничения
История · было → стало
Состояние обновляется каждые 5 секунд, пока блок открыт. Процент показывается только там, где известен объём работы. Пауза останавливает продолжение этапа; текущий запрос к источнику может завершиться.
Takahashi K, Inanami O, Kuwabara M
Аннотация
PURPOSE: To examine the roles ofintracellular calcium in radiation-induced apoptosis of MOLT-4 cells, the effects of intracellular calcium chelator BAPTA-AM on the induction of apoptosis and the activation of apoptosis-relating enzymes SAPK/JNK and caspase-3 were studied.
MATERIALS AND METHODS: MOLT-4 cells pretreated with 5 microM BAPTA-AM were exposed to X-rays. DNA fragmentation, the expression of phosphorylated SAPK/JNK and the activation of caspase-3 and calcium concentration were measured by agarose gel electrophoresis, Western blotting and spectrofluorometry.
RESULTS: Time-dependent ladder-like DNA fragmentation was observed at 4h, 5 h and 6 h after exposure to 15 Gy of X-rays. This fragmentation was significantly attenuated by pretreatment with BAPTA-AM up to 5 h after irradiation, but the attenuation due to BAPTA-AM was no longer detectable at 6 h. Activation of SAPK/JNK and caspase-3 was observed at 1 and 4 h after X-irradiation, respectively, and BAPTA-AM retarded the activation for 2 h. The pretreatment with BAPTA-AM was found to suppress the increase of calcium concentration for 6h after irradiation.
CONCLUSION: These results revealed that chelation of calcium merely delayed the onset of the radiation-induced apoptosis regulated by the activation of SAPK/JNK and caspase-3, and calcium was not essential for the induction of apoptosis in X-irradiated MOLT-4 cells.
MATERIALS AND METHODS: MOLT-4 cells pretreated with 5 microM BAPTA-AM were exposed to X-rays. DNA fragmentation, the expression of phosphorylated SAPK/JNK and the activation of caspase-3 and calcium concentration were measured by agarose gel electrophoresis, Western blotting and spectrofluorometry.
RESULTS: Time-dependent ladder-like DNA fragmentation was observed at 4h, 5 h and 6 h after exposure to 15 Gy of X-rays. This fragmentation was significantly attenuated by pretreatment with BAPTA-AM up to 5 h after irradiation, but the attenuation due to BAPTA-AM was no longer detectable at 6 h. Activation of SAPK/JNK and caspase-3 was observed at 1 and 4 h after X-irradiation, respectively, and BAPTA-AM retarded the activation for 2 h. The pretreatment with BAPTA-AM was found to suppress the increase of calcium concentration for 6h after irradiation.
CONCLUSION: These results revealed that chelation of calcium merely delayed the onset of the radiation-induced apoptosis regulated by the activation of SAPK/JNK and caspase-3, and calcium was not essential for the induction of apoptosis in X-irradiated MOLT-4 cells.