title: Effects of homocysteine on ERK signaling and cell proliferation in fetal neural stem cells in vitro.
abstract: The aim of the present study was to determine if the excitatory amino acid homocysteine (Hcy) alters ERK signaling and cell proliferation in fetal neural stem cells (NSCs) in vitro. NSCs were isolated from fetal rats and grown in serum-free suspension medium. The cells were identified as NSCs by their expression of immunoreactive Sox2. NSCs were assigned to one of four treatment groups: vehicle control, low-dose Hcy group (Hcy-L, medium contained 30 μmol/L Hcy), middle-dose Hcy group (Hcy-M, 100 μmol/L Hcy) and high-dose Hcy group (Hcy-H, 300 μmol/L Hcy). Cell proliferation was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Protein expression levels of ERK1/2 and phosphorylated ERK1/2 were detected by Western blot. The effects of Hcy on NSC death, including apoptosis, were assessed by using flow cytometry and trypan blue exclusion. The results showed that NSCs grew as neurospheres in the serum-free medium. Hcy decreased ERK1/2 protein phosphorylation and NSC proliferation, but it did not induce cell death or apoptosis within the concentration from 30 to 300 μmol/L. The above results are consistent with the hypothesis that Hcy decreases fetal NSC proliferation by inhibiting ERK signaling.
authors.affiliation: Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University, Tianjin, 300070, China.
authors.forename: Hai
authors.initials: H
authors.lastname: Yan
authors.forename: Xumei
authors.initials: X
authors.lastname: Zhang
authors.forename: Suhui
authors.initials: S
authors.lastname: Luo
authors.forename: Huan
authors.initials: H
authors.lastname: Liu
authors.forename: Xuan
authors.initials: X
authors.lastname: Wang
authors.forename: Yuxia
authors.initials: Y
authors.lastname: Gao
authors.forename: John X
authors.initials: JX
authors.lastname: Wilson
authors.forename: Guowei
authors.initials: G
authors.lastname: Huang
mesh_terms: D000818:Animals; D017209:Apoptosis; D002452:Cell Count; D049109:Cell Proliferation / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D016895:Culture Media, Serum-Free; D005260:Female; D053686:Fetal Stem Cells / Q000166:cytology / Q000187:drug effects*; D006710:Homocysteine / Q000494:pharmacology*; D020935:MAP Kinase Signaling System; D058953:Neural Stem Cells / Q000166:cytology / Q000187:drug effects*; D010766:Phosphorylation; D011247:Pregnancy; D051381:Rats; D055748:SOXB1 Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D016895:Culture Media, Serum-Free; D055748:SOXB1 Transcription Factors; C527784:Sox2 protein, rat; D006710:Homocysteine