Comparison of newly generated doublecortin-immunoreactive neuronal progenitors in the main olfactory bulb among variously aged gerbils.
In the present study, we investigated age-related differences in neuronal progenitors in the gerbil main olfactory bulb (MOB) using doublecortin (DCX), a marker for neuronal progenitors which differentiate into neurons in the brain. No difference in the number of neuronal nuclei (NeuN)-immunoreactive neurons was found in the MOB at variously aged gerbils. At postnatal month (PM) 1, DCX immunoreaction was detected in all layers of the MOB except for the olfactory nerve layer. At this time point, DCX-immunoreactive cells (neuronal progenitors) were very abundant; however, they did not have fully developed-processes. From PM 3, the number of DCX-immunoreactive neuronal progenitors was decreased with age. At PM 6, DCX-immunoreactive cells showed very well-developed processes. In western blot analysis, DCX protein level in the MOB was highest at PM 1. Thereafter, levels of DCX protein were decreased with age. In the subventricular zone of the lateral ventricle, the number of Ki-67-immunoractive cells (proliferating cells) was also significantly decreased with age. In addition, increases of α-synuclein-immunoreactive structures were observed in the MOB with age. These results suggest that decrease in DCX-immunoreactive neuronal progenitors and its protein levels in the MOB with age may be associated with reduction of cell proliferation in the SVZ and with an increase in α-synuclein in the MOB.
Choi
Jung Hoon
JH
Department of Anatomy and Neurobiology, College of Medicine, Hallym University, Chuncheon, South Korea.
Yoo
Ki-Yeon
KY
Lee
Choong Hyun
CH
Park
Ok Kyu
OK
Yan
Bing Chun
BC
Li
Hua
H
Hwang
In Koo
IK
Park
Jeong Ho
JH
Kim
Sung Koo
SK
Won
Moo-Ho
MH
D000375:Aging / Q000378:metabolism*; D000818:Animals; D034961:Antigens, Nuclear / Q000378:metabolism; D049109:Cell Proliferation; D000089622:Doublecortin Domain Proteins; D000089662:Doublecortin Protein; D005849:Gerbillinae; D007150:Immunohistochemistry; D008297:Male; D008869:Microtubule-Associated Proteins / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000378:metabolism; D058953:Neural Stem Cells / Q000166:cytology / Q000378:metabolism*; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D009479:Neuropeptides / Q000378:metabolism*; D009830:Olfactory Bulb / Q000166:cytology / Q000378:metabolism*; D051844:alpha-Synuclein / Q000378:metabolism
D034961:Antigens, Nuclear; C000714848:Dcx protein, rat; D000089622:Doublecortin Domain Proteins; D000089662:Doublecortin Protein; D008869:Microtubule-Associated Proteins; D009419:Nerve Tissue Proteins; D009479:Neuropeptides; C546339:Rbfox3 protein, rat; D051844:alpha-Synuclein