Primate early life stress leads to long-term mild hippocampal decreases in corticosteroid receptor expression.
BACKGROUND
Expression of mineralocorticoid receptor (MR) and glucocorticoid receptor (GR) genes are moderately reduced in several brain regions in depression. These reductions could be partly due to early life stress (ELS), which predicts emotional disorders. Controlled primate studies are important to test whether ELS sufficient to induce long-term emotional changes also induces long-term altered MR and/or GR brain expression.


METHODS
In the common marmoset, ELS of daily 30-120-min social isolation across month-1 resulted in some long-term changes in homeostasis and emotional behavior. In some of these same subjects, the aim of this study was to use marmoset-specific riboprobes to determine whether ELS produced long-term effects on brain MR and GR gene expression.


RESULTS
At adolescence, relative to control subjects, ELS marmosets exhibited mildly reduced messenger RNA signal for both MR (-15%, p = .05) and GR (-13%, p = .02) in hippocampus-primarily CA1-2-but not in prefrontal cortex, other cortical regions, or hypothalamus.


CONCLUSIONS
In adolescent marmoset monkey brains, reduced hippocampal expression of MR and GR are consistent chronic-indicators of ELS. It is unlikely that these chronic, mild, specific reductions were acute-mediators of the observed long-term emotional effects of ELS. However, they do suggest involvement of hippocampal MR/GR in the neurodevelopmental effects of ELS.
Arabadzisz
Dimitrula
D
Laboratory of Behavioral Neurobiology, Swiss Federal Institute of Technology, Zürich, Switzerland.
Diaz-Heijtz
Rochellys
R
Knuesel
Irene
I
Weber
Elisabeth
E
Pilloud
Sonia
S
Dettling
Andrea C
AC
Feldon
Joram
J
Law
Amanda J
AJ
Harrison
Paul J
PJ
Pryce
Christopher R
CR
D000818:Animals; D002144:Callithrix; D006624:Hippocampus / Q000378:metabolism*; D017403:In Situ Hybridization; D008426:Maternal Deprivation; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011965:Receptors, Glucocorticoid / Q000235:genetics / Q000378:metabolism*; D018161:Receptors, Mineralocorticoid / Q000235:genetics / Q000378:metabolism*; D012934:Social Isolation; D013315:Stress, Psychological / Q000235:genetics / Q000378:metabolism; D013995:Time
D012333:RNA, Messenger; D011965:Receptors, Glucocorticoid; D018161:Receptors, Mineralocorticoid