Neuroendocrinology and Neuroimmunology
Author: Analía Mercedes Ferreyra | email: analiaferreyra0@gmail.com
Analía Mercedes Ferreyra 1°, Crystal Vincent 2°, Alfonso Soler Bistue 3°, Marc Dionne 2°, Esteban Javier Beckwith 1°
1° Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE) – UBA – CONICET, Argentina
2° MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, UK
3° Instituto de Investigaciones Biotecnológicas (IIBio)-CONICET – UNSAM, Argentina
The interplay between sleep and immunity is well established, and this relationship is bidirectional in nature. On one hand, during the regular sleep-wake cycle, many immune parameters oscillate and, globally, at the beginning of the rest period a pro-Inflammatory state is constituted, while wakefulness is characterized by anti-inflammatory activities. There is evidence that sleep has a supportive role in initiating an adaptive immune response and stimulates the acquisition of immunological memory. On the other hand, host behavioural changes are among the most apparent effects of infection. The so-called “sickness behaviour” can involve a variety of symptoms, including anorexia, depression, and changed activity levels. Employing Drosophila melanogaster, we modelled systemic infections by thoracic injections of an array of bacteria. We followed the behaviour of the infected flies with a video-recording tracking device and showed that these animals respond with a marked increase in activity, which leads to a drop in sleep levels. These changes upon activation of the immune system are dependent on the presence of the Toll pathway in the fat body and the brain. Currently, we are focused on evaluating how chronic sleep restriction, achieved by a combination of video-tracking and robotics, influences the progression of bacterial infections, and how the different pathways of the immune system present in insects, and conserved in vertebrates, are affected by lack of sleep.