Department of Surgery, Fukushima Medical University, Fukushima, Japan.
Pancreas. 2012 Mar;41(2):245-52. doi: 10.1097/MPA.0b013e31822461c7.
We recently reported that mitomycin C (MMC) treatment and subsequent culture of islets significantly prolongs graft survival in allotransplantation and xenotransplantation models. The present study was performed to determine the changes in morphology and signal transduction in pancreatic islets after MMC treatment.
Freshly isolated rat islets were treated with 10 μg/mL MMC for 30 minutes and then cultured for up to 3 days. The samples were processed for immunohistologic studies and electron microscopic examination at various times after treatment. A DNA fragmentation assay was performed to detect apoptotic cell death. Western blotting was performed to determine the effects of MMC on signal transduction.
As early as 4 hours after culture, the islets showed central damage; most cells were necrotic and stained with anti-high mobility group box 1 antibody, and a few were apoptotic. The ratio of the damaged area to the whole area was significantly decreased after MMC treatment. Western blotting showed that MMC treatment increased the levels of activated forms of p53 and p21, whereas levels of the activated forms of Akt and caspase-3 were unchanged.
Mitomycin C treatment protects islets from the progression of central damage during culture. The p53-p21 pathway might be involved in these effects.
MMC - mitomycin C, HMGB1 - high mobility group box 1.
我们最近报道称，丝裂霉素 C（MMC）处理和随后的胰岛培养可显著延长同种异体和异种移植模型中的移植物存活时间。本研究旨在确定 MMC 处理后胰岛的形态和信号转导变化。
将新鲜分离的大鼠胰岛用 10μg/ml MMC 处理 30 分钟，然后培养长达 3 天。在处理后不同时间点对样品进行免疫组织化学研究和电子显微镜检查。进行 DNA 片段化测定以检测细胞凋亡。进行 Western 印迹以确定 MMC 对信号转导的影响。
培养 4 小时后，胰岛即出现中心损伤；大多数细胞发生坏死，并被抗高迁移率族蛋白 B1（HMGB1）抗体染色，少数为凋亡。经 MMC 处理后，损伤面积与总面积的比值明显降低。Western 印迹显示 MMC 处理增加了 p53 和 p21 的激活形式水平，而 Akt 和 caspase-3 的激活形式水平不变。
丝裂霉素 C 处理可防止胰岛在培养过程中发生中心损伤进展。p53-p21 途径可能参与这些作用。
MMC-丝裂霉素 C，HMGB1-高迁移率族蛋白 B1。
