Purpose: The possibility of 1.5-2 times increase of animals life span (LS) by reduction of cell proliferation rate and a metabolism had been shown earlier on fish, amphibians, reptiles, birds, and mammals (Prokhorov, 1999, 2003). The purpose of the present work to analyze an opportunity to increase LS the men and animals more than in 1.5-2 times.
Materials and methods: We used the cultures of Chinese hamster transformed cells and Human embryonic diploid fibroblasts growing without sub cultivation but with periodical medium change. The time passed from cell seeding up to culture "death" we call "the life span". The culture "death" is the moment when the cell number becomes less then 10 % of cell number at saturation density.
Results: It is possible to receive cultures of normal cells (by introduction of telomerase gene) where the cells divisions become unlimited, cells do not lose the specialization and do not become cancerous (Bodnar, 1998). We believe, that replanting such cells in old organs will lead to rejuvenation of them and whole organism, and finally to increase organisms LF. Meanwhile introduction of young cells in old organism does not always bring to expected effect: young cells perish. We have established that normal cells and cells with unlimited potential of division perish in culture if they do not have space for duplication. The last was shown by us on mans normal fibroblasts and on the transformed Chinese hamster cells. The growth space in an old organism or in old culture is occupied by old cells enabled to division. Old cells perish because they are cannot to divide, and young cells not divide because of external pressure of old cells, i.e. because of contact inhibition. As result, the young cells are situated in equal conditions as the old cells, and also perish, not having a chance to divide.
Conclusion: For LS increase (more than 1.5-2 times) it is necessary to develop ways of old cells elimination from an organism, and with subsequent their replacement by young cells.