EFFECTS OF OXYGEN CONCENTRATION AND PRESSURE ONDrosophila melanogaster: OXIDATIVE STRESS, MITOCHONDRIAL ACTIVITY, AND SURVIVORSHIP

Abstract

Organisms are known to be equipped with an adaptive plasticity as the phenotype of traits in response to the imposed environmental challenges as they grow and develop. In this study, the effects of extreme changes in oxygen availability and atmospheric pressure on physiological phenotypes of Drosophila melanogaster were investigated to explore adaptation mechanisms. The changes in citrate synthase activity (CSA), lifespan, and behavioral function in different atmospheric conditions were evaluated. In the CAS test, hyperoxia significantly increased CSA; both hypoxia and hyperbaric conditions caused a significant decrease in CSA. In the survivorship test, all changed atmospheric conditions caused a significant reduction in lifespan. The lifespan reduced more after hypoxia exposure than after hyperbaria exposure. In behavioral function test, when mechanical agitation was conducted, bang-sensitive flies showed a stereotypical sequence of initial muscle spasm, paralysis, and recovery. The percentage of individuals that displayed paralysis or seizure was measured on the following day and after 2 weeks from each exposure. The majority of flies showed seizure behavior 15 days after exposure, especially after 3 h of exposure. The percentage of individuals that did not undergo paralysis or seizure and was able to move in the vial, was also tested. The number of flies that moved and raised the higher level of the vial decreased after exposure. Animal's speed decreased significantly 15 days after exposure to extreme environmental conditions. In summary, the alteration of oxygen availability and atmospheric pressure may lead to significant changes in mitochondria mass, lifespan, and behavioral function in D. melanogaster.

Iron Sulfur and Molybdenum Cofactor Enzymes Regulate the Drosophila Life Cycle by Controlling Cell Metabolism

“…To do so, it uses specialized muscles (Iwamoto, 2011 ), which receive oxygen directly through the trachea (Lehmann and Schützner, 2010 ), respiring over 90% of the oxygen to sustain flight (Suarez, 2000 ). Mitochondria are key to this action (Levenbook and Williams, 1956 ) and ambient oxygen concentrations alter flight performance (Skandalis et al, 2011 ; Bosco et al, 2015 ; Shiehzadegan et al, 2017 ). If Fe-S respiratory enzymes are affected either by aging (Ferguson et al, 2005 ) or by mutation (Walker et al, 2006 ; Godenschwege et al, 2009 ; Martin et al, 2009 ; Vrailas-Mortimer et al, 2011 ; Oka et al, 2015 ), muscle pathology ensues.…”

Inhibition of mitochondrial respiration under hypoxia and increased antioxidant activity after reoxygenation of Tribolium castaneum

“…In D . melanogaster , hypoxia treatment for 90 min significantly inhibited citrate synthase and resulted in a marked reduction in life span [ 59 ]. Diminished mitochondrial aerobic capacity and oxidative phosphorylation are always associated with a reduced life span.…”

“…Diminished mitochondrial aerobic capacity and oxidative phosphorylation are always associated with a reduced life span. Altered mitochondrial function could lead to a reduced life span because of accumulated damage in cell and tissue [ 59 ].…”

A Link between Atmospheric Pressure and Fertility of Drosophila Laboratory Strains

“…As for Drosophila melanogaster, there is evidence that changes in atmospheric pressure could affect mating behavior [14][15][16], lifespan [17,18], walking speed and flight performance [19]. Having been involved in neurohormonal stress response investigations in D. melanogaster model for many years [20,21], we always do our best to standardize the conditions of our research as much as possible in order to have a control group, which is not influenced by any stressors.…”