Mechanisms of staurosporine induced apoptosis in a human corneal endothelial cell line
| Autor: | S Herrag, C. Chiquet, Jean-Marc Dumollard, Boudard D, L Campos, Gilles Thuret, J Bednarz, Philippe Gain |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2003 |
| Předmět: |
Programmed cell death
Cell type Blotting Western Caspase 3 Apoptosis Cell Line Cellular and Molecular Neuroscience medicine Staurosporine Humans Enzyme Inhibitors Caspase biology Endothelium Corneal Immunohistochemistry Sensory Systems eye diseases Cell biology Endothelial stem cell Enzyme Activation Ophthalmology Laboratory Science Microscopy Electron Caspases biology.protein sense organs Poly(ADP-ribose) Polymerases Intracellular medicine.drug |
| Popis: | A poptosis is one of the most fundamental biological processes in mammals, in which individual cells die by activating an intrinsic suicide mechanism. Over the past decade, it has become evident that a family of cysteine proteases, so far comprising 14 members,1 related to interleukin-1b converting enzyme (ICE) and termed caspases,2 plays a crucial part in apoptosis. After activation, caspases cleave their specific substrate proteins after aspartic acid residues. Some so called “downstream” caspases thus cleave numerous targets that are essential for cell survival. For example, caspase-3, which is one of the main downstream caspases,3,4 cleaves, among other targets, poly(ADP-ribose) polymerase (PARP), which is normally responsible for DNA repair.5 PARP cleavage is thus one of the hallmarks of caspase-3 activation Activation of apoptosis in human corneal endothelial cells (HCECs) was recently highlighted during hypothermic storage of corneas6 and in organ culture.7,8 Moreover, excessive apoptosis seems to be implicated in the pathogenesis of Fuchs’ dystrophy.9,10 However, the molecular mechanisms responsible for human corneal endothelial apoptosis remain largely unknown. Only the implication of caspase-3 has been suggested in immunohistochemical tests by Albon.7 Analysis of the intracellular mechanisms of endothelial apoptosis in a whole human cornea is difficult for several reasons. Firstly, these cells are particularly well protected against in vivo cell death in normal conditions, since physiological loss is only about 0.6% per year in adults.11 Moreover, the monolayer structure of the endothelium hampers histological observation, and also allows rapid shedding of altered cells,12 which makes concurrent observation of a large number of cells at the same stage of cell death unlikely. In vitro, unmodified HCEC cultures derived from adult donors provide only a limited number of cells. They quickly dedifferentiate, lose their morphological characteristics, and lead to reproducibility problems.13–16 This limits the use of such cultures for techniques requiring large quantities of cells, and justifies study on a cell line to develop an in vitro model of endothelial apoptosis. Apoptosis of cultured human endothelial cells was induced by the mycotoxin staurosporine, which has been shown to induce apoptosis in a wide variety of cell types.17,18 Many important mechanisms involved in apoptosis have been demonstrated in staurosporine induced apoptosis models.18,19 The intracellular signalling pathways of staurosporine triggered apoptosis are however not fully known, and depend on cell type. While there seem to be phases common to all staurosporine induced apoptosis,17 this one can however include caspase dependent20,21 or caspase independent22–24 phases, whose relative importance varies according to cell type. The aim of this study was to establish a model of staurosporine induced apoptosis of a human corneal endothelial cell line, and to explore whether caspase-3 is involved in this model of cell death. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|