Fasting increase the preference for palatable food in Drosophila melanogaster

ECKERT, F.B; DE TONI, D.; TRICHES, F.F.; RAMOS HRYB ANA BELÉN; RAMIREZ, M. F.; LINO DE OLIVEIRA, C.

Florianopolis

Congreso; II SIMPÓSIO BRASILEIRO DE NEUROPSICOFARMACOLOGIA; 2019

UFSC

Background: Drosophila melanogaster may be an organism suitable to replace vertebrates in neuroscience research [1][2]. Drosophilidae mayexpress preferences for palatable foods [3]. Objectives: In this study, we investigated the capacity of fasting to increase the preference of D. melanogaster for palatable food (banana). Methods: Forty adult D. melanogaster wild flies (males, 20/group) were anesthetized in ice (1-3 min) to sexing, transferred to glass containers with corn medium and then assigned to fasted or fed groups. Fasting flies stayed in a falcon tube containing a paper soaked water for 16 hours in groups to avoid socialisolation. For behavioural testing, flies were transferred individually using a entomological vacuum cleaner to a plus maze with four arms, three containing agar and one containing banana. The positions of the arms wererandomly selected. All the tests were videotaped for 900s under dark conditions to avoid positive-phototaxis influencing the behavior. Ethological analysis was performed with the aid of EthoWatcher®. We analyzed the time that flies spent in the arms and in the center of the maze. All data is expressed as mean±SEM. Results: Fed flies spent more time in the center of the maze (591.8±32.03s) than fasted flies (385,5±44,40s), T-test, p=0.00073. Control group flies had a lowerpresence in the banana arm (180.15±35.89) when compared to the fasting group (408.75±52.29), the difference was significant (T-test, p=0.00116). Flies of the fed group explored all arms containing agar slightly longer (Agar 1=19.85±4.24; Agar 2=25.9±5.46; Agar 3=45.25±13.00) than fasted group (Agar 1=17.75±4.90; Agar 2=19.5±9.77; Agar 3=37.2±9.59), (T-test, Agar 1 p=0.75394; Agar 2=0.58062; Agar 3=0.63024). Conclusion: In general, the flies had a greater presence in the center when compared to the arms, however, when fasting, the presence of the flies in the armcontaining banana increased significantly indicating that fasting influenced their permanence in the plusmaze. But, more tests are needed, using females and with a larger sample number.