Zellveränderungen der Lungenkarzinomzelllinie A549 durch Kaltlagerung

A donated organ is usually stored under hypothermic conditions, to limit the metabolism of the cells. The questions whether this cold-induced injury can be influenced by ferrop- tosis or necroptosis inhibitors and whether a chloride-rich or chloride-poor incubation solution leads to further injury were addressed in this thesis. Monolayers of the human lung cancer cell line A549 were incubated in Krebs-Henseleit buffer (KH; Cl-: 128 milli- molar (mM)) and in the chloride-poor modification of this buffer (KH-Lac; lactobionate: 123 mM, Cl-: 5 mM) ± desferal (1 mM), necrostatin (50 micromolar (μM)), ferrostatin (5 μM) or dimethylsulfoxid (DMSO) (solvent) for 168 hours at 4 degrees Celsius (°C). Subsequently, the cells were rewarmed to 37 °C in Dulbecco’s Modified Eagle medium (DMEM). Cell injury (release of cytosolic lactate dehydrogenase (LDH), intercalation of propidium iodide in the deoxyribonucleic acid, lipid peroxidation) and morphological changes were assessed after cold storage and during rewarming. In addition, the cellular adenosine triphosphate (ATP) content was measured. The cold storage resulted in an in- creased LDH release of 84.3 ± 7.3 % in KH and of 67.8 ± 16.9 % in KH-Lac. Desferal and ferrostatin, but not necrostatin, inhibited it nearly completely (≤ 6 % in KH, ≤ 10 % in KH-Lac). Rewarming after cold storage in KH + desferal/ferrostatin led to no further injury, whereas rewarming after cold storage in KH-Lac + desferal/ferrostatin led to mas- sive cell blebbing with an increasing injury. After a rewarming period of 2 hours, cells which were incubated in KH – in the presence of the inhibitors – exhibited an initial ATP content, but cells which were incubated in KH-Lac, showed till 50 % lesser cellular ATP content. The presence of the iron chelator desferal as well as the ferroptosis inhibitor ferrostatin during cold storage showed a significant protective effect, whereas the necrop- tosis inhibitor necrostatin was not able to inhibit cell injury. Furthermore, the absence of chloride during cold storage led to an irreversible injury in the rewarming period, which could be eliminated by the presence of chloride in the cold storage solution. The decreased cellular ATP content after rewarming of chloride-poor incubated cells probably indicates a mitochondrial impairment and could be the reason for the late cell injury.