Development and lifespan duration of Drosophila melanogaster at the larval development under hypoxia and hyperoxia

Abstract

Various environmental factors can affect metabolic processes, physiological parameters and the lifespan of the whole organism. Since aging can be considered as part of development in accordance with the "developmental theory of aging", we can assume that development duration correlates with adult lifespan. Understanding how organisms react to different concentrations of O2 is an area of intense scientific study. It is known that ambient oxygen level affects body size, growth and development rates, cell cycle duration in Drosophila melanogaster, but data on the impact on lifespan remain controversial. In this study, we studied the influence of hypoxia (10% O2) and hyperoxia (40% O2) at the larval stage of development on the duration of Drosophila development and lifespan. Drosophila kept in atmospheric air (21% O2) was used as control. At the imago stage all the flies were kept in atmospheric air conditions. The results were presented as survival curves and average and maximum lifespan were calculated. The development duration of Drosophila melanogaster, which were kept under hypoxia, increased by one day compared to control and did not change at hyperoxia. Average and maximum life span significantly decreased at hyperoxia (average – by 17% in males and 10% in females, maximum – by 17% in males, p<0,001). Hypoxia in different ways influenced males and females. The average lifespan of males did not significantly change and the maximum – increased by 11% (p<0.001). In females, hypoxia during development led to a decrease in average lifespan by 18% and in maximum life span by 8%. The data obtained during our investigation allow us to conclude that the concentration of oxygen in the environment at the stage of development of Drosophila affects their life expectancy at the stage of imago, which can be explained by epigenetic mechanisms. Hyperoxia at the developmental stage adversely affected the life expectancy of fruit flies, probably due to the adverse effects of free-radical processes. Sex differences in the effects of hypoxia at the developmental stage were revealed. In female flies, it led to negative effects, while in males development under hypoxic conditions extended life span, probably due to the phenomenon of hormesis.