INTERPRETATION OF DATA ABOUT THE IMPACT OF BIOLOGICALLY ACTIVE COMPOUNDS ON VIABILITY OF CULTURED CELLS OF VARIOUS ORIGIN FROM A GERONTOLOGICAL POINT OF VIEW

Problems related to the interpretation of data obtained during testing of potential geroprotectors in cytogerontological experiments are considered. It is emphasized that such compounds/physical factors should influence on the processes leading to the age-related increase of death probability of multicellular organisms (primarily — of man, in whose aging gerontologists are mainly interested). However, in the authors’ opinion, compounds which cure age-related diseases unlikely could be classified as geroprotectors. It is noted, that, in the model systems using cultured cells, researchers, as a rule, evaluate their viability criteria of which, to a great extent, depend on the aging theory shared by the experimenters. Besides, it is very important what cells are used in the studies — normal or transformed cells of multicellular organisms, unicellular eukaryotic or prokaryotic organisms, etc. In particular, biologically active compounds which decrease the viability of cultured cancer cells may increase the life span of experimental animals and humans, as well as compounds which increase the viability of normal cultured cells. Various problems with interpretation of data obtained with the Hayflick model, the stationary phase aging model, and the cell kinetics model, as well as in experiments on evaluation of cell colony-forming efficiency are analyzed. The approaches discussed are illustrated on the example of the results from gerontological investigations of a famous mTOR inhibitor, rapamycin. It is assumed that factors retarding the stationary phase aging (chronological aging) of cultured cells are, apparently, the most promising geroprotectors although the specific mechanisms of their action may vary considerably.

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