Dietary protein defines stress resistance, oxidative damages and antioxidant defense system in Drosophila melanogaster

Abstract

Dietary interventions have been previously shown to influence lifespan in diverse model organisms. Manipulations with macronutrients content including protein and amino acids have a significant impact on various fitness and behavioral traits in the fruit fly Drosophila melanogaster. Therefore, we asked if yeast amount of the diet could influence stress resistance and antioxidant defense system in Drosophila. We examined the effects of four diets differing in the relative level of yeast, as a source of protein, on resistance to cold, heat, starvation and oxidative stress induced by menadione as well as activities of antioxidant enzymes and levels of oxidative stress markers. Protein restriction as well protein-enriched diet led to a reduction of survival under starvation and oxidative stress conditions. However, enhanced resistance to heat shock was affected by high yeast concentration in the diet. Also, protein-rich diets resulted in higher activity of antioxidant enzymes. Increased levels of protein thiols, low-molecule mass thiols, lipid peroxides in response to high yeast concentration in the diet were detected in females only. Thus, we can assume that consumption of a high protein diet could induce oxidative stress in fruit fly.

Keywords

• diet
• fruit fly
• metabolism
• nutrition
• oxidative stress