Cigarette smoke exposure of prediabetic Drosophila melanogaster affects survival, oxygen consumption, thermal and ionic stress endurance.

Cigarette smoke (CS) exposure in Drosophila Melanogaster leads to a COPD like phenotype whereas flies on High sugar diet (HSD) develop hyperglycemia and obesity. There is no fly model investigating whether smoking aggravates the HSD observed effects. The aim of our study was the investigation of the effects of CS exposure on D. melanogaster fed with HSD on their body weight, metabolic rate, locomotion, stress resistance and survival. Flies were fed with normal diet (ND) or HSD for 10 ten days. CS exposure via inhalation, 15 minutes daily for 10 days, was performed. Afterwards, the flies weight was measured, their metabolic rate was assessed by respirometry, and their locomotion by the negative geotaxis assay. Additionally, their endurance in stress conditions like chill comma, desiccation, and ionic stress were assessed. In other experiments, their 10-day survival was measured. CS exposure significantly affected male metabolic rate, locomotor activity and body weight of both sexes. HSD significantly affected the recovery of female flies after chill comma. HSD and CS significantly increased desiccation endurance but decreased female ionic stress endurance. Finally, CS exposure and HSD significantly reduced fly survival in both sexes. Our findings indicate that CS affects the metabolic rate, the locomotion, body weight and survival, while HSD affects the survival of D. melanogaster under various stress conditions. These findings could serve as the basis for the development of a D. Melanogaster model for studying the interactions of smoking as a second hit in a state of hyperglycaemia, a characteristic of Type 2 Diabetes Mellitus.