Abstract
We have previously shown (Vaiserman A. M. et al., 2012) that the dietary supplementation with histone deacetylase inhibitor sodium butyrate (SB) throughout adult stage or both pre-adult and adult stages results in increase of life span (LS) in Drosophila melanogaster. It was suggested that because of the impact of SB on epigenetic control of gene function and therefore possibility of long-term effects, SB supplementation during the larval stage of development only may also increase adult LS. The present study was carried out to verify that assumption. The nutritional supplementation with SB during the larval stage at the concentration of 20 mmol/l resulted in a significant increase in the male mean LS; maximum LS was significantly increased in males treated with SB at concentrations of 10, 20 and 40 mmol/l. Female mean LS was unchanged following the SB administration; maximum LS was significantly increased in female group treated with SB at concentration of 10 mmol/l only. Female reproductive activity was the same in all groups. To test the hypothesis that the observed long-term effect of SB exposure on the flies' longevity could be caused by the induction of persistent epigenetic changes, the levels of expression of the longevity-associated genes (hsp70, sir2 and InR) were determined. The expression level of sir2 gene, known to mediate longevity in the fly through a pathway related to calorie restriction, in the group treated at the larval stage with 20 mmol/l SB was significantly higher after the stress (starvation) than in the control group.
