[8-oxo-2'-deoxyguanosine accumulation in DNA from "stationary phase aging" cultured cells].

The 8-oxo-dG/dG ratio in DNA of cultured transformed Chinese hamster cells was analyzed during their "stationary phase aging". Amount of 8-oxo-dG and dG in DNA hydrolyzate was evaluated by HPLC-EC. The cells grew and "aged" for 15 days. As expected, the 8-oxo-dG/dG ratio increased with cell "age". It did not change significantly from 4th to 8th day (6.26 x 10(-5) and 4.42 x 10(-5), correspondingly) and then abruptly increased to 15th day of "age" (22.40 x 10(-5)). The results are in accordance with the conception of cell proliferation restriction as the starting mechanism of ageing and the method can be used for evaluation of cell culture biological age when testing new compounds for their geroprotector or geropromoter activity.

[Potential geroprotector properties of the extract of reindeer antler powder in experiments on cultured cells].

Preparations from deer antlers are well known by their multiple medicinal properties. In particular, their health-giving effect on senescing organism has been repeatedly shown. In the study we investigated effect of water extract of reindeer mature antler powder (ERAP) on the kinetics of growth and "stationary phase aging" of HeLa (clone 11) cell line. Cell suspension was placed in the wells of 24-well plastic tissue culture plates with seeding density of 15 10(3)/cm2. The growth medium contained ERAP at 0, 10 or 100 microl/ml. In every 1-3 days microscopic evaluation of live cell number in the wells has been made. It turned out, that ERAP at 10 microl/ml increased proliferation rate of HeLa cells as well as their saturation density, i.e. acted as a geroprotector. The result was also confirmed by the observed "stationary phase aging" slowing down leading to increase of the "average life span" of cell culture. However, effect of ERAP at 100 microl/ml was different. In that case the evident decrease of cell culture saturation density was observed indicating increase of the culture "biological age". Besides, the cell death began earlier leading to decrease of the "average life span" of the cell culture. We think that ERAP contains some compounds with geroprotector activity as well as some geropromoters, or cell proliferation inhibitors. At the lower ERAP concentration in growth medium content of geropromoter(s) is too low for its effect manifestation and the evident "rejuvenation" of the cell culture is observed. At the higher concentration of ERAP (100 microl/ml) the content of geropromoter(s) reaches the "working" value and this not only masks the effect of geroprotector(s) but also leads to the cell culture "senescence".