Adrenalectomy increases neurogenesis but not PSA-NCAM expression in aged dentate gyrus.
Ageing is accompanied by a decline in neurogenesis and in polysialylated isoforms of neural cell adhesion molecule (PSA-NCAM) expression within the hippocampus and by elevated basal levels of circulating corticosterone. In a companion study, we demonstrated that suppression of corticosterone by adrenalectomy increased neurogenesis and PSA-NCAM expression in the dentate gyrus of adult rats. Here we show that adrenalectomy increased neurogenesis in this structure in old rats, as measured by the incorporation of 5-bromo-2'-deoxyuridine in neuronal progenitors. This effect was prevented by corticosterone replacement. In contrast, PSA-NCAM expression remained unchanged in comparison with controls. Thus, in the aged brain, stem cells are still present and able to enter the cell cycle. This may point to ways of protecting or treating age-related cognitive impairments.
Montaron
M F
MF
INSERM U259, Bordeaux, France.
Petry
K G
KG
Rodriguez
J J
JJ
Marinelli
M
M
Aurousseau
C
C
Rougon
G
G
Le Moal
M
M
Abrous
D N
DN
D000311:Adrenal Glands / Q000502:physiology*; D000315:Adrenalectomy; D000375:Aging / Q000378:metabolism*; D000818:Animals; D002455:Cell Division / Q000502:physiology; D002470:Cell Survival / Q000502:physiology; D003345:Corticosterone / Q000378:metabolism; D018891:Dentate Gyrus / Q000254:growth & development / Q000378:metabolism*; D008297:Male; D039842:Neural Cell Adhesion Molecule L1; D019006:Neural Cell Adhesion Molecules / Q000096:biosynthesis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012636:Secretory Rate; D012794:Sialic Acids / Q000096:biosynthesis*
D039842:Neural Cell Adhesion Molecule L1; D019006:Neural Cell Adhesion Molecules; D012794:Sialic Acids; C103469:polysialyl neural cell adhesion molecule; D003345:Corticosterone