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Konsman. Neuroimmunol Neuroinflammation 2016;3:207-14 Neuroimmunology and
DOI: 10.20517/2347-8659.2016.19
Neuroinflammation

www.nnjournal.net
Review Open Access

Immune-to-brain signaling and substrates

of altered behavior during inflammation

Jan Pieter Konsman

CNRS UMR 5287, Institute for Cognitive and Integrative Neurosciences in Aquitaine (INCIA), University of Bordeaux, 33076 Bordeaux, France.
Correspondence to: Dr. Jan Pieter Konsman, CNRS UMR 5287, Institute for Cognitive and Integrative Neurosciences in Aquitaine (INCIA),
University of Bordeaux, 146 rue Léo Saignat, 33076 Bordeaux, France. Email: jan-pieter.konsman@u-bordeaux.fr
How to cite this article: Konsman JP. Immune-to-brain signaling and substrates of altered behavior during inflammation. Neuroimmunol
Neuroinflammation 2016;3:207-14.

ABSTRACT
Article history: During the systemic inflammatory response to acute infection, and when in a safe
Received: 18-04-2016 environment, endothermic mammals typically display reduced activity and food intake,
Accepted: 10-08-2016 increased sleep, and the adoption of a curled-up position. These changes in behavior, in
Published: 26-09-2016 concert with fever, are adaptive in that they contribute to host survival. The present review
addresses the immune-to-brain signaling pathways as well as possible neural substrates
Key words: mediating reduced exploration and food intake during acute systemic inflammation. These
Behavior, involve rapid activation of peripheral nerves and glutamatergic brainstem circuits as well
cytokines, as slower IL-1β action in the brain activating limbic and possibly ventral hypothalamic
inflammation structures. Although mostly adaptive acutely, behavioral changes during inflammation may
also reflect brain dysfunction in severe sepsis-associated delirium or become maladaptive
and result in depression due to medical conditions that involve long-term inflammatory
episodes with pain or discomfort. The mechanisms underlying these conditions are
presently ill-understood even though neuroinflammation and neurodegeneration occur
during and subsequent to sepsis-associated brain dysfunction, respectively.

INTRODUCTION fever is an energetically costly response often requiring
an increase in metabolism of 30-50%. Text books of
[4]
Fever and reduced activity and food intake as human and veterinary medicine often have mentioned
adaptive host responses to infection reduced activity and appetite along with the occurrence
The finding in the 1970s that peripheral administration of fever during infectious disease. From an energy
[4]
of non-steroid anti-inflammatory drug-type antipyretics balance point of view on endotherms, it makes sense
lowered survival of different species of animals after to reduce energy expenditure in the form of physical
their inoculation with bacteria provided a conclusive activity, such as exploration of one’s environment,
piece evidence in favor of the idea that fever was during fever. But, given the adaptive value as well as
beneficial for survival of infected organisms. [1-3] But the high energy costs of increasing body temperature in
Quick Response Code:
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