Chronic mild stress in mice decreases peripheral cytokine and increases central cytokine expression independently of IL-10 regulation of the cytokine network.
OBJECTIVE
Accumulating evidence indicates that stress leads to an increased expression of pro-inflammatory cytokines such as interleukin (IL)-6. The production and action of pro-inflammatory cytokines are down-regulated by anti-inflammatory cytokines such as IL-10. This makes IL-10-deficient mice a potentially useful model to assess the effects of stress on cytokine production.


METHODS
In the present study, IL-10-deficient mice were compared to wild-type mice in their behavioural and cytokine response to a chronic mild stress procedure.


RESULTS
The 3-week chronic mild stress decreased body weight gain and sucrose consumption. It also resulted in a decreased expression of peripheral IL-1beta and IL-6 and an increased expression of brain IL-6. This last change in IL-6 was correlated to body weight loss in stressed mice. However, IL-10-deficient mice did not differ from wild-type mice in their response to the chronic mild stress procedure, despite substantial differences in functioning of the cytokine network.


CONCLUSIONS
These results are interpreted in the context of the relationship between cytokines and behaviour.
Mormède
Cécile
C
INRA-INSERM U394, Neurobiologie Intégrative, Institut François Magendie, Bordeaux, France.
Castanon
Nathalie
N
Médina
Chantal
C
Moze
Elisabeth
E
Lestage
Jacques
J
Neveu
Pierre J
PJ
Dantzer
Robert
R
D000818:Animals; D001069:Appetite Regulation / Q000276:immunology; D001835:Body Weight / Q000276:immunology; D001921:Brain / Q000276:immunology* / Q000378:metabolism; D002908:Chronic Disease; D003345:Corticosterone / Q000097:blood; D016207:Cytokines / Q000276:immunology* / Q000378:metabolism; D004195:Disease Models, Animal; D015536:Down-Regulation / Q000276:immunology; D005260:Female; D006400:Hematocrit; D007375:Interleukin-1 / Q000378:metabolism; D016753:Interleukin-10 / Q000172:deficiency* / Q000235:genetics; D015850:Interleukin-6 / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D013312:Stress, Physiological / Q000276:immunology* / Q000378:metabolism; D013395:Sucrose / Q000378:metabolism
D016207:Cytokines; D007375:Interleukin-1; D015850:Interleukin-6; D016753:Interleukin-10; D013395:Sucrose; D003345:Corticosterone