...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Proceedings of the National Academy of Sciences of the United States of America >Apoptosis induced by environmental stresses and amphotericin B in Candida albicans
【24h】

Apoptosis induced by environmental stresses and amphotericin B in Candida albicans

机译：环境压力和两性霉素B诱导白色念珠菌凋亡

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

New antifungal agents are urgently required to combat life-threatening infections caused by opportunistic fungal pathogens like Candida albicans. The manipulation of endogenous fungal programmed cell death responses could provide a basis for future therapies. Here we assess the physiology of death in C. albicans in response to environmental stresses (acetic acid and hydrogen peroxide) and an antifungal agent (amphotericin B). Exposure of C. albicans to 40-60 mM acetic acid, 5-10 mM hydrogen peroxide, or 4-8μg·ml~(-1) amphotericin B produced cellular changes reminiscent of mammalian apoptosis. Nonviable cells that excluded propidium iodide displayed the apoptotic marker phosphatidylserine (as shown by annexin-V-FITC labeling), were terminal deoxynucleoti-dyltransferase-mediated dUTP nick end labeling (TUNEL)-positive (indicating nuclease-mediated double-strand DNA breakage), and produced reactive oxygen species. Ultrastructural changes in apoptotic cells included chromatin condensation and margination, separation of the nuclear envelope, and nuclear fragmentation. C. albicans cells treated at higher doses of these compounds showed cellular changes characteristic of necrosis. Necrotic cells displayed reduced TUNEL staining, a lack of surface phosphatidylserine, limited reactive oxygen species production, and an inability to exclude propidium iodide. Necrotic cells lacked defined nuclei and showed extensive intracellular vacuolization. Apoptosis in C. albicans was associated with an accumulation of cells in the G_2/M phase of the cell cycle, and under some apoptosis-inducing conditions, significant proportions of yeast cells switched to hyphal growth before dying. This is a demonstration of apoptosis in a medically important fungal pathogen.
机译：迫切需要新的抗真菌剂来对抗由机会性真菌病原体（如白色念珠菌）引起的威胁生命的感染。内源性真菌程序性细胞死亡反应的操纵可为将来的治疗提供基础。在这里，我们评估响应环境压力（乙酸和过氧化氢）和抗真菌剂（两性霉素B）而在白色念珠菌中死亡的生理机制。白色念珠菌暴露于40-60 mM的乙酸，5-10 mM的过氧化氢或4-8μg·ml〜（-1）的两性霉素B产生的细胞变化让人联想到哺乳动物的凋亡。排除碘化丙啶的无生命细胞显示凋亡标记物磷脂酰丝氨酸（如膜联蛋白-V-FITC标记所示），是末端脱氧核苷酸-二基转移酶介导的dUTP缺口末端标记（TUNEL）阳性（表明核酸酶介导的双链DNA断裂）。 ，并产生活性氧。凋亡细胞的超微结构变化包括染色质浓缩和边缘化，核被膜分离和核碎裂。用较高剂量的这些化合物处理的白色念珠菌细胞显示出坏死的细胞变化特征。坏死细胞显示出减少的TUNEL染色，缺乏表面磷脂酰丝氨酸，活性氧产生受限以及无法排除碘化丙啶。坏死细胞缺乏明确的细胞核，并显示出广泛的细胞内空泡化。白色念珠菌的凋亡与细胞周期的G_2 / M期中的细胞积累有关，在某些细胞凋亡诱导条件下，大量酵母细胞在死亡前转变为菌丝生长。这证明了在医学上重要的真菌病原体中的细胞凋亡。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号