title: Age-associated changes in the subcellular localization of phosphorylated p38 MAPK in human granulosa cells.
abstract: p38 MAPK (p38) plays pivotal roles in aging and reproductive physiology. Nevertheless, involvement of p38 in female reproductive aging is uncertain. To improve knowledge of the role of p38 in age-associated reproductive failure, the expression and subcellular localization of phosphorylated p38 was investigated in human granulosa cells. p38 was 7-fold more activated in cells from older subjects than in those from younger subjects. Similar results were obtained in human granulosa-like KGN cells treated with hydrogen peroxide (H(2)O(2)). Interestingly, phosphorylated p38 was detected in the nucleus less frequently in older cells than in younger cells (Younger: 58.6%; Older: 29.8%, P< 0.01). Similarly cytoplasmic localization of phosphorylated p38 in KGN cells was observed after treatment with H(2)O(2). The activation and cytoplasmic localization of p38 in H(2)O(2)-treated KGN cells were blocked by N-acetylcysteine and SB203580. Although the p38 activators, FSH and tumor necrosis factor-α, induced a similar localization of phosphorylated p38 in KGN cells, the expression and localization patterns of p38 were distinct from those in older granulosa cells and H(2)O(2)-treated KGN cells. These results indicate that the characteristic localization of p38 in older granulosa cells is induced by oxidative stress.
authors.affiliation: Division of Reproductive Medicine, Department of Perinatal Medicine and Maternal Care, National Center for Child Health and Development, 2-10-1 Okura, Setagaya-ku, Tokyo 157-8535, Japan.
authors.forename: Megumu
authors.initials: M
authors.lastname: Ito
authors.forename: Kenji
authors.initials: K
authors.lastname: Miyado
authors.forename: Koji
authors.initials: K
authors.lastname: Nakagawa
authors.forename: Miho
authors.initials: M
authors.lastname: Muraki
authors.forename: Misa
authors.initials: M
authors.lastname: Imai
authors.forename: Naomi
authors.initials: N
authors.lastname: Yamakawa
authors.forename: Junwen
authors.initials: J
authors.lastname: Qin
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Hosoi
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Saito
authors.forename: Yuji
authors.initials: Y
authors.lastname: Takahashi
mesh_terms: D000328:Adult; D000367:Age Factors; D002460:Cell Line; D004789:Enzyme Activation / Q000187:drug effects; D005260:Female; D005640:Follicle Stimulating Hormone / Q000494:pharmacology; D006107:Granulosa Cells / Q000201:enzymology*; D006801:Humans; D020935:MAP Kinase Signaling System; D010766:Phosphorylation; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D048051:p38 Mitogen-Activated Protein Kinases / Q000032:analysis / Q000378:metabolism* / Q000502:physiology
chemical_list: D014409:Tumor Necrosis Factor-alpha; D005640:Follicle Stimulating Hormone; D048051:p38 Mitogen-Activated Protein Kinases