title: Changes of gene expression profiles during neuronal differentiation of central nervous system precursors treated with ascorbic acid.
abstract: Ascorbic acid (AA) has been shown to increase the yield of dopaminergic (DA) neurons derived from basic fibroblast growth factor (bFGF)-expanded mesencephalic precursors. To understand the molecular mechanisms underlying this phenomenon, we used cDNA microarray analysis to examine differential expression of neuronal genes following AA treatment. The putative precursor cells were isolated from E13 rat ventral mesencephalons and expanded in the presence of bFGF. Cells were incubated in mitogen-free media supplemented with 200 microM AA or were left untreated as a control, and total RNA was isolated at different time points (expansion stage and 1, 3, and 6 days after induction of differentiation) and subjected to cDNA microarray analysis. Differentiation was evaluated by Western blot analysis and immunocytochemistry of neuron-specific markers. AA treatment of the mesencephalic precursors increased the expression of neuronal (MAP2) and astrocytic (glial fibrillary acidic protein) markers and the percentage of tyrosine hydroxylase (TH)-positive cells. The microarray analysis revealed that 12 known genes were up-regulated and 20 known genes were down-regulated in expansion-stage AA-treated cells. Six days after the induction of differentiation, AA-treated cells showed up-regulation of 48 known genes and down-regulation of 5 known genes. Our results identified several proteins, such as transferrin, S-100, and somatostatin, as being differentially regulated in AA-treated mesencephalic precursors. This novel result may lead to a better understanding of the molecular mechanisms underlying the AA-induced differentiation of mesencephalic precursors into DA neurons and may form the basis for improved DA neuronal production for treatment of Parkinson's disease patients.
authors.affiliation: Department of Biochemistry, College of Medicine, Hanyang University, Seoul, Republic of Korea.
authors.forename: Dong-Hyun
authors.initials: DH
authors.lastname: Yu
authors.forename: Ki-Hwan
authors.initials: KH
authors.lastname: Lee
authors.forename: Ji-Yeon
authors.initials: JY
authors.lastname: Lee
authors.forename: Sujong
authors.initials: S
authors.lastname: Kim
authors.forename: Dong-Mi
authors.initials: DM
authors.lastname: Shin
authors.forename: Jin-Hyuk
authors.initials: JH
authors.lastname: Kim
authors.forename: Young-Seek
authors.initials: YS
authors.lastname: Lee
authors.forename: Yeon-Sook
authors.initials: YS
authors.lastname: Lee
authors.forename: Sun Kyung
authors.initials: SK
authors.lastname: Oh
authors.forename: Shin Yong
authors.initials: SY
authors.lastname: Moon
authors.forename: Sang-Hun
authors.initials: SH
authors.lastname: Lee
authors.forename: Yong-Sung
authors.initials: YS
authors.lastname: Lee
mesh_terms: D000818:Animals; D001205:Ascorbic Acid / Q000494:pharmacology*; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology*; D002478:Cells, Cultured; D002490:Central Nervous System / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D005260:Female; D020869:Gene Expression Profiling / Q000379:methods; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D006133:Growth Substances / Q000494:pharmacology*; D009474:Neurons / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley; D013234:Stem Cells / Q000166:cytology* / Q000187:drug effects / Q000502:physiology
chemical_list: D006133:Growth Substances; D001205:Ascorbic Acid