title: The effect of hypoxia preconditioning on DNA methyltransferase and PP1γ in hippocampus of hypoxia preconditioned mice.
abstract: It is well known that hypoxia preconditioning can increase hypoxic tolerance by changing the expressions of some genes in the brain. DNA methylation is important for regulating gene expression and is catalyzed by DNA methyltransferase (DNMT), an enzyme that is abundant in the brain. However, the impact of hypoxia preconditioning on DNA methylation remains unknown. In the current study, mice were randomly divided into three groups: blank control group with no exposure to hypoxia (H0), the hypoxia control group exposed to hypoxia once (H1), and the hypoxia preconditioning group exposed to 4 runs of hypoxia (H4). The mRNA and protein levels of three kinds of DNMTs and the activity of total DMNT were measured. Protein phosphatase 1(PP1)γ, which critically regulates neuroprotective pathways in brain, was measured in mRNA and protein activity and promoter methylation. DNMT1 was unchanged in H1 and H4, while DNMT3A and DNMT3B were decreased in H4. The mRNA and protein levels of PP1γ were decreased in H4. However, there was no detectable change in the level of DNA methylation of the promoter of PP1γ (-321 bp to 95 bp). These findings suggest that DNA methylation may have a role in hypoxia neuroprotection, and the change of PP1γ, which did not depend on the change of its promoter (-321 bp to 95bp) DNA methylation, may be involved in neuroprotection.
authors.affiliation: 1 Biomedicine Research Center and Basic Medical College, The First Affiliated Hospital of BaoTou Medical College , Inner Mongolia, People's Republic of China .
authors.forename: Shu
authors.initials: S
authors.lastname: Zhang
authors.forename: Yanbo
authors.initials: Y
authors.lastname: Zhang
authors.forename: Shuyuan
authors.initials: S
authors.lastname: Jiang
authors.forename: You
authors.initials: Y
authors.lastname: Liu
authors.forename: Lihua
authors.initials: L
authors.lastname: Huang
authors.forename: Tao
authors.initials: T
authors.lastname: Zhang
authors.forename: Guowei
authors.initials: G
authors.lastname: Lu
authors.forename: Kerui
authors.initials: K
authors.lastname: Gong
authors.forename: Xunming
authors.initials: X
authors.lastname: Ji
authors.forename: Guo
authors.initials: G
authors.lastname: Shao
mesh_terms: D000818:Animals; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000235:genetics* / Q000378:metabolism; D019175:DNA Methylation / Q000235:genetics*; D000090205:DNA Methyltransferase 3A; D015870:Gene Expression; D006624:Hippocampus / Q000201:enzymology*; D000860:Hypoxia / Q000201:enzymology / Q000235:genetics*; D008297:Male; D051379:Mice; D054645:Protein Phosphatase 1 / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D011897:Random Allocation; D000097584:DNA Methyltransferase 3B
chemical_list: D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases; D000090205:DNA Methyltransferase 3A; D054645:Protein Phosphatase 1; D012333:RNA, Messenger; D000097584:DNA Methyltransferase 3B; C000715535:Dnmt3a protein, mouse; C000619381:Dnmt1 protein, mouse
keywords: DNA methyltransferase; hypoxia preconditioning; mice; protein phosphatase 1 (PP1)