The stress response and immune system share, borrow, and reconfigure their physiological network elements: Evidence from the insects

• Published in: Hormones and behavior 2017-02, Vol.88, p.25-30
• Main Author: Adamo, Shelley A.
• Format: Article
• Language: English
• Subjects: Adipokinetic hormone; Animals; Antimicrobial peptide; Apolipoproteins - metabolism; Ecoimmunology; Immune System - physiology; Insect Hormones - metabolism; Insecta; Lipid transport proteins; Octopamine; Octopamine - metabolism; Oligopeptides - metabolism; Psychoneuroimmunology; Pyrrolidonecarboxylic Acid - analogs & derivatives; Pyrrolidonecarboxylic Acid - metabolism; Stress, Physiological - immunology
• ISSN: 0018-506X; 1095-6867
• DOI: 10.1016/j.yhbeh.2016.10.003

The classic biomedical view is that stress hormone effects on the immune system are largely pathological, especially if the stress is chronic. However, more recent interpretations have focused on the potential adaptive function of these effects. This paper examines stress response-immune system interactions from a physiological network perspective, using insects because of their simpler physiology. For example, stress hormones can reduce disease resistance, yet activating an immune response results in the release of stress hormones in both vertebrates and invertebrates. From a network perspective, this phenomenon is consistent with the ‘sharing’ of the energy-releasing ability of stress hormones by both the stress response and the immune system. Stress-induced immunosuppression is consistent with the stress response ‘borrowing’ molecular components from the immune system to increase the capacity of stress-relevant physiological processes (i.e. a trade off). The insect stress hormones octopamine and adipokinetic hormone can also ‘reconfigure’ the immune system to help compensate for the loss of some of the immune system's molecular resources (e.g. apolipophorin III). This view helps explain seemingly maladaptive interactions between the stress response and immune system. The adaptiveness of stress hormone effects on individual immune components may be apparent only from the perspective of the whole organism. These broad principles will apply to both vertebrates and invertebrates. •Stress responses and the immune system form an integrated defense system.•The networks share, borrow and reconfigure each other's components.•Stress hormone effects on immune function are adaptive from a network perspective.