Failure of neuronal maturation in Alzheimer disease dentate gyrus.
The dentate gyrus, an important anatomic structure of the hippocampal formation, is one of the major areas in which neurogenesis takes place in the adult mammalian brain. Neurogenesis in the dentate gyrus is thought to play an important role in hippocampus-dependent learning and memory. Neurogenesis has been reported to be increased in the dentate gyrus of patients with Alzheimer disease, but it is not known whether the newly generated neurons differentiate into mature neurons. In this study, the expression of the mature neuronal marker high molecular weight microtubule-associated protein (MAP) isoforms MAP2a and b was found to be dramatically decreased in Alzheimer disease dentate gyrus, as determined by immunohistochemistry and in situ hybridization. The total MAP2, including expression of the immature neuronal marker, the MAP2c isoform, was less affected. These findings suggest that newly generated neurons in Alzheimer disease dentate gyrus do not become mature neurons, although neuroproliferation is increased.
Li
Bin
B
Department of Neurochemistry, NYS Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, USA.
Yamamori
Hidenaga
H
Tatebayashi
Yoshitaka
Y
Shafit-Zagardo
Bridget
B
Tanimukai
Hitoshi
H
Chen
She
S
Iqbal
Khalid
K
Grundke-Iqbal
Inge
I
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000473:pathology*; D000818:Animals; D016022:Case-Control Studies; D049109:Cell Proliferation; D018891:Dentate Gyrus / Q000473:pathology* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D008875:Middle Aged; D009474:Neurons / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar
C489788:MAP2 protein, human; D008869:Microtubule-Associated Proteins