Role of survivin in acute lung injury: epithelial cells of mice and humans

Abstract

Survivin, an inhibitor of apoptosis, regulates cell division and is a potential target for anticancer drugs because many cancers express high survivin levels. However, whether survivin would be toxic to human lung cells and tissues has not been determined. This report clarified the involvement of survivin in acute lung injury. We used immunohistochemical analysis, immunoelectron microscopy, and real-time reverse transcription-quantitative polymerase chain reaction to study survivin expression and localization in injured mouse and human lungs. We also used cultured human lung epithelial cells (BEAS-2B and A549) to study survivin cytoprotection. Nuclei and cytoplasm of epithelial cells in day 3 and day 7 models of bleomycin-injured lung showed survivin-positive results, which is consistent with upregulated survivin mRNA expression. These nuclei also evidenced double positive findings for proliferating cell nuclear antigen and survivin. Day 7 models had similar Smac/DIABLO-positive and survivin-positive cell distributions. The cytoplasm and nuclei of epithelial cells in lesions with diffuse alveolar damage manifested strong survivin-positive findings. Bleomycin stimulation in both epithelial cell lines upregulated expression of survivin and apoptosis-related molecules. Suppression of survivin expression with small interfering RNA rendered human lung epithelial cells susceptible to bleomycin-induced damage, with markedly upregulated activation of caspase-3, caspase-7, poly (ADP-ribose) polymerase, and lactate dehydrogenase activity and an increased number of dead cells compared with mock small interfering RNA-treated cells. Overexpression of survivin via transfection resulted in these epithelial cells being resistant to bleomycin-induced cell damage, with reduced activation of apoptosis-related molecules and lactate dehydrogenase activity and fewer dead cells compared with results for mock-transfected cells. Survivin, acting at the epithelial cell level that depends partly on apoptosis inhibition, is therefore a key mediator of cytoprotection in acute lung injury. Understanding the precise role of survivin in normal lung cells is required for the development of therapeutic survivin.

Inhibition of endotoxin-induced airway epithelial cell injury by a novel family of pyrrol derivates

“…27 Numerous experimental studies have used human A549 alveolar and BEAS-2B bronchial epithelial cell lines to examine the acute lung inflammatory response induced by LPS, as an acceptable, validated, and suitable in vitro airway epithelial injury model based on the initial steps of the development of sepsis and ARDS [11][12][13][14][15][16]25,[28][29][30] and continue being extensively used. [31][32][33][34][35] We selected E. coli LPS because it has been used in most endotoxin-induced lung injury models 36,37 and LPS is a key pathogen recognition molecule for sepsis 27 that induces apoptosis in lung cells. 38 Previous reports examining the efficacy of molecules on the LPS-induced activation of inflammatory markers in the lung, or before evaluating the potential in vivo anti-inflammatory properties, have used a similar in vitro epithelial cell injury model to the one we used.…”

“…Second, we did not use primary alveolar epithelial cells; however, there is a plethora of published studies validating the use of human BEAS-2B and A549 cells as an acceptable model of epithelial cell injury and for studying the LPS-induced effects in the airway epithelium. [11][12][13][14][15][16]25,[28][29][30][31][32][33][34][35] Third, further studies are needed to elucidate whether there are other mechanisms by which the pyrrol compound DTA0118 elicits its anti-inflammatory and antiapoptotic activities. Fourth, TLR4, Ikβα, and β-actin were not adjusted for the cell number.…”

Advances in Understanding of the Pathogenesis of Acute Respiratory Distress Syndrome

“…Epithelial cell death can be manipulated through use of survivin, an inhibitor of apoptosis. A study combining a mouse model of lung injury and in vitro culture of human alveolar epithelial cells demonstrated a protective effect through reduction in apoptosis-related molecules [124]. …”

Neue Erkenntnisse zur Pathogenese des akuten Atemnotsyndroms

“…Der Tod von Epithelzellen lässt sich durch Anwendung von Survivin manipulieren, einem Inhibitor der Apoptose. Eine Studie, in der ein Mausmodell der Lungenschädigung mit der In-vitro-Kultur von menschlichen Alveolarepithelzellen kombiniert wurde, zeigte eine Schutzwirkung durch Reduktion der Apoptose-assoziierten Moleküle [124]. …”