The Effects Of Simulated Microgravity On Fragile Sites Expression In Human Peripheral Blood Lymphocyte

Space environment is so complex that astronauts entering into space will facevariety of changes in psychology and physiology level, and the space microgravityis the main affecting factor. The preliminary studies by analyzing the expressionrate of chromosome fragile sites, chromatid breaks and isochromatid breaks inpeople peripheral blood lymphocyte had found that simulated microgravity effectfor72h can influence chromosome fragile sites expression in peripheral bloodlymphocyte. In this study, the blood from25-35year-old healthy male were used asexperimental material and simulated microgravity with the two dimensional rotatingwall vessels system (2D-RWVS). The human peripheral blood lymphocytes werecultured in common medium and low folic acid medium respectively, and thechromosome numbers were counted. In order to further study the influence ofsimulated microgravity effect on chromosome structure in human PBL,5cases ofhuman PBL were cultured in the common culture medium to determine whethersimulated microgravity effect for72h can induce the expression of chromosomefragile sites. Otherwise, another5cases of peripheral blood lymphocyte werecultured in low folic acid medium. The results show that simulated microgravity for72h did not affect the numbers of chromosome in human peripheral bloodlymphocytes, and only the effects of simulated microgravity could not induce theexpression of fragile sites. However, by low folic acid with Aphidicolin together toinduce the expression of fragile sites, and the number of all fragile sites expressionand the number of fragile sites expression in chromosome1and2, FRA3B, FRA11FFRA16D were detected by chromosome G banding. The results showed that thenumber of fragile site expression in the simulated microgravity group almostdoubled the ground control. All these results indicated that simulated microgravitycan increase the chromosomal instability.