title: 4-Methylumbelliferone inhibits the phosphorylation of hyaluronan synthase 2 induced by 12-O-tetradecanoyl-phorbol-13-acetate.
abstract: The effect of 4-methylumbelliferone (MU), a hyaluronan synthase-suppressor, on O-linked β-Nacetylglucosaminylation (O-GlcNAcylation) was investigated in cultured human skin fibroblasts, and we found that MU stimulated O-GlcNAcylation of the cellular proteins. Since O-GlcNAcylation affects protein phosphorylation via Ser/Thr kinases, we examined the effect of MU on both the phosphorylation of hyaluronan synthase 2 (HAS2) and hyaluronan production. The cells were cultured in the presence or absence of 12-O-tetradecanoyl-phorbol-13-acetate (TPA) and MU independently or in combination. The protein fraction of each cell culture was extracted and divided into 2 parts-phosphorylated and non-phosphorylated fractions-by immobilized metal-affinity chromatography. The hyaluronan level in the medium was determined by an ELISA-like assay. Addition of MU decreased the level of hyaluronan in the medium and that of HAS2 in the phosphorylated protein fraction. On the contrary, the addition of TPA increased the levels of both of them. Interestingly, the combination of TPA and MU lowered the levels of them in treated cells as compared to those in untreated control cells. These results suggest that TPA activated protein kinase C (PKC), which stimulates the phosphorylation of HAS2, and increased hyaluronan production. Further, MU may inhibit the phosphorylation of HAS2 by PKC through the stimulation of O-GlcNAcylation.
authors.affiliation: Department of Biomedical Sciences, Hirosaki University Graduate School of Health Sciences, 66-1 Hon-cho, Hirosaki 036-8564, Japan.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Kuroda
authors.forename: Kosuke
authors.initials: K
authors.lastname: Kasai
authors.forename: Naoki
authors.initials: N
authors.lastname: Nanashima
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nozaka
authors.forename: Manabu
authors.initials: M
authors.lastname: Nakano
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Chiba
authors.forename: Masahiko
authors.initials: M
authors.lastname: Yoneda
authors.forename: Toshiya
authors.initials: T
authors.lastname: Nakamura
mesh_terms: D002478:Cells, Cultured; D005347:Fibroblasts / Q000187:drug effects / Q000201:enzymology; D005786:Gene Expression Regulation / Q000187:drug effects; D014453:Glucuronosyltransferase / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D006801:Humans; D000076002:Hyaluronan Synthases; D006820:Hyaluronic Acid / Q000096:biosynthesis; D006923:Hymecromone / Q000031:analogs & derivatives* / Q000494:pharmacology; D010766:Phosphorylation / Q000187:drug effects; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
chemical_list: D006923:Hymecromone; D006820:Hyaluronic Acid; D014453:Glucuronosyltransferase; C101754:HAS2 protein, human; D000076002:Hyaluronan Synthases; D013755:Tetradecanoylphorbol Acetate