Effect of Dalargin On Apoptosis of L929 Fibroblasts During Cold Stress

Abstract

BACKGROUND: The search for compounds that can prevent cold stress-attributed apoptosis is of immediate interest. In this regard, the use of neuropeptides, in particular synthetic leu-enkephalin, as protectors is promising, due to their ability to prevent the development of apoptosis under some stresses. OBJECTIVE: To study apoptotic phenomena after cold stress and to evaluate the protective effect of dalargin on these processes. MATERIALS AND METHODS: The study was performed on a L929 fibroblast line. The impact of cold stress and the protective effect of dalargin on apoptosis against cold stress were evaluated using morphological parameters, distortion of cell membrane asymmetry and release of cytochrome C into the cell cytoplasm. To assess the proliferative potential of fibroblasts, mechanical damage to the monolayer was modeled as a scratch wound. RESULTS: The study showed that cold stress induced apoptosis in L929 fibroblasts and reduced proliferation in the fibroblast monolayers. Conspicuous apoptotic changes were found to develop only after a certain time after cold exposure, when the cells were returned to normothermia. Dalargin was demonstrated to exert a protective effect on proliferation and against apoptosis during cold stress. Using the opioid receptor antagonist naloxone, we revealed that the protective mechanism of dalargin appeared to be due to activation of δ -opioid receptors of L929 fibroblasts, which affected the development of apoptosis. CONCLUSION: In addition to their fundamental value, these findings are of practical importance since neuropeptides, in particular dalargin, added to perfusion solutions and media for hypothermic preservation of organs and cells, can improve their efficiency.