Regulation of E-box DNA binding during in vivo and in vitro activation of rat and human hepatic stellate cells: evidence for expression of MyoD.

K. J. Vincent, E. Jones, M. J. Arthur, D. E. Smart, J. E. Trim, Matthew Christopher Wright, D. A. Mann

    Research output: Contribution to journalArticle

    27 Citations (Scopus)

    Abstract

    Background-Activation of hepatic stellate cells (HSCs) to a myofibroblastic phenotype is a key event in liver fibrosis. Identification of transcription factors with activities that are modulated during HSC activation will improve our understanding of the molecular events controlling HSC activation.

    Aims-To determine if changes in E-box DNA binding activity occur during in vitro and in vivo activation of rat and human HSCs and to investigate mechanisms underlying any observed changes.

    Methods-Nuclear extracts were prepared from rat HSCs isolated and cultured from normal and carbon tetrachloride injured rat livers and from HSCs isolated from human liver. EMSA analysis of E-box DNA binding activity was performed on nuclear extracts to determine changes during HSC activation. Western and northern blot analysis of MyoD and Id1 basic helix-loop-helix (bHLH) proteins was performed to confirm expression in HSC. Results-HSC activation was associated with inducible expression of two low mobility E-box binding complexes that were immunoreactive with an anti-MyoD antibody. MyoD mRNA expression was found at similar levels in freshly isolated and activated HSCs; in contrast, MyoD protein expression was elevated in activated HSCs. Activation of rat HSCs was accompanied by reduced expression of the inhibitory bHLH protein Id1.

    Conclusions-In vitro and in vivo activation of rat and human HSCs is accompanied by induction of MyoD binding to E-box DNA sequences which appears to be mechanistically associated with elevated MyoD protein expression and reduced expression of the inhibitory Id1 protein. Clarification of the role of MyoD and Id1 proteins in HSC activation and liver fibrogenesis is now required.

    Original languageEnglish
    Pages (from-to)713-717
    Number of pages4
    JournalGut
    Volume5
    DOIs
    Publication statusPublished - 2001

    Keywords

    • liver fibrosis
    • hepatic stellate cell
    • basic helix-loop-helix transcription factors
    • MyoD
    • Id1
    • FAT-STORING CELLS
    • KAPPA-B-FAMILY
    • TISSUE INHIBITOR
    • GENE-EXPRESSION
    • HLH PROTEINS
    • ID PROTEINS
    • ITO-CELLS
    • FIBROSIS
    • LIVER
    • MYOD

    Cite this

    Regulation of E-box DNA binding during in vivo and in vitro activation of rat and human hepatic stellate cells: evidence for expression of MyoD. / Vincent, K. J.; Jones, E.; Arthur, M. J.; Smart, D. E.; Trim, J. E.; Wright, Matthew Christopher; Mann, D. A.

    In: Gut, Vol. 5, 2001, p. 713-717.

    Research output: Contribution to journalArticle

    Vincent, K. J. ; Jones, E. ; Arthur, M. J. ; Smart, D. E. ; Trim, J. E. ; Wright, Matthew Christopher ; Mann, D. A. / Regulation of E-box DNA binding during in vivo and in vitro activation of rat and human hepatic stellate cells: evidence for expression of MyoD. In: Gut. 2001 ; Vol. 5. pp. 713-717.
    @article{7ff41b5a80e44a0ca8a0a88af930da43,
    title = "Regulation of E-box DNA binding during in vivo and in vitro activation of rat and human hepatic stellate cells: evidence for expression of MyoD.",
    abstract = "Background-Activation of hepatic stellate cells (HSCs) to a myofibroblastic phenotype is a key event in liver fibrosis. Identification of transcription factors with activities that are modulated during HSC activation will improve our understanding of the molecular events controlling HSC activation.Aims-To determine if changes in E-box DNA binding activity occur during in vitro and in vivo activation of rat and human HSCs and to investigate mechanisms underlying any observed changes.Methods-Nuclear extracts were prepared from rat HSCs isolated and cultured from normal and carbon tetrachloride injured rat livers and from HSCs isolated from human liver. EMSA analysis of E-box DNA binding activity was performed on nuclear extracts to determine changes during HSC activation. Western and northern blot analysis of MyoD and Id1 basic helix-loop-helix (bHLH) proteins was performed to confirm expression in HSC. Results-HSC activation was associated with inducible expression of two low mobility E-box binding complexes that were immunoreactive with an anti-MyoD antibody. MyoD mRNA expression was found at similar levels in freshly isolated and activated HSCs; in contrast, MyoD protein expression was elevated in activated HSCs. Activation of rat HSCs was accompanied by reduced expression of the inhibitory bHLH protein Id1.Conclusions-In vitro and in vivo activation of rat and human HSCs is accompanied by induction of MyoD binding to E-box DNA sequences which appears to be mechanistically associated with elevated MyoD protein expression and reduced expression of the inhibitory Id1 protein. Clarification of the role of MyoD and Id1 proteins in HSC activation and liver fibrogenesis is now required.",
    keywords = "liver fibrosis, hepatic stellate cell, basic helix-loop-helix transcription factors, MyoD, Id1, FAT-STORING CELLS, KAPPA-B-FAMILY, TISSUE INHIBITOR, GENE-EXPRESSION, HLH PROTEINS, ID PROTEINS, ITO-CELLS, FIBROSIS, LIVER, MYOD",
    author = "Vincent, {K. J.} and E. Jones and Arthur, {M. J.} and Smart, {D. E.} and Trim, {J. E.} and Wright, {Matthew Christopher} and Mann, {D. A.}",
    year = "2001",
    doi = "10.1136/gut.49.5.713",
    language = "English",
    volume = "5",
    pages = "713--717",
    journal = "Gut",
    issn = "0017-5749",
    publisher = "BMJ Publishing Group",

    }

    TY - JOUR

    T1 - Regulation of E-box DNA binding during in vivo and in vitro activation of rat and human hepatic stellate cells: evidence for expression of MyoD.

    AU - Vincent, K. J.

    AU - Jones, E.

    AU - Arthur, M. J.

    AU - Smart, D. E.

    AU - Trim, J. E.

    AU - Wright, Matthew Christopher

    AU - Mann, D. A.

    PY - 2001

    Y1 - 2001

    N2 - Background-Activation of hepatic stellate cells (HSCs) to a myofibroblastic phenotype is a key event in liver fibrosis. Identification of transcription factors with activities that are modulated during HSC activation will improve our understanding of the molecular events controlling HSC activation.Aims-To determine if changes in E-box DNA binding activity occur during in vitro and in vivo activation of rat and human HSCs and to investigate mechanisms underlying any observed changes.Methods-Nuclear extracts were prepared from rat HSCs isolated and cultured from normal and carbon tetrachloride injured rat livers and from HSCs isolated from human liver. EMSA analysis of E-box DNA binding activity was performed on nuclear extracts to determine changes during HSC activation. Western and northern blot analysis of MyoD and Id1 basic helix-loop-helix (bHLH) proteins was performed to confirm expression in HSC. Results-HSC activation was associated with inducible expression of two low mobility E-box binding complexes that were immunoreactive with an anti-MyoD antibody. MyoD mRNA expression was found at similar levels in freshly isolated and activated HSCs; in contrast, MyoD protein expression was elevated in activated HSCs. Activation of rat HSCs was accompanied by reduced expression of the inhibitory bHLH protein Id1.Conclusions-In vitro and in vivo activation of rat and human HSCs is accompanied by induction of MyoD binding to E-box DNA sequences which appears to be mechanistically associated with elevated MyoD protein expression and reduced expression of the inhibitory Id1 protein. Clarification of the role of MyoD and Id1 proteins in HSC activation and liver fibrogenesis is now required.

    AB - Background-Activation of hepatic stellate cells (HSCs) to a myofibroblastic phenotype is a key event in liver fibrosis. Identification of transcription factors with activities that are modulated during HSC activation will improve our understanding of the molecular events controlling HSC activation.Aims-To determine if changes in E-box DNA binding activity occur during in vitro and in vivo activation of rat and human HSCs and to investigate mechanisms underlying any observed changes.Methods-Nuclear extracts were prepared from rat HSCs isolated and cultured from normal and carbon tetrachloride injured rat livers and from HSCs isolated from human liver. EMSA analysis of E-box DNA binding activity was performed on nuclear extracts to determine changes during HSC activation. Western and northern blot analysis of MyoD and Id1 basic helix-loop-helix (bHLH) proteins was performed to confirm expression in HSC. Results-HSC activation was associated with inducible expression of two low mobility E-box binding complexes that were immunoreactive with an anti-MyoD antibody. MyoD mRNA expression was found at similar levels in freshly isolated and activated HSCs; in contrast, MyoD protein expression was elevated in activated HSCs. Activation of rat HSCs was accompanied by reduced expression of the inhibitory bHLH protein Id1.Conclusions-In vitro and in vivo activation of rat and human HSCs is accompanied by induction of MyoD binding to E-box DNA sequences which appears to be mechanistically associated with elevated MyoD protein expression and reduced expression of the inhibitory Id1 protein. Clarification of the role of MyoD and Id1 proteins in HSC activation and liver fibrogenesis is now required.

    KW - liver fibrosis

    KW - hepatic stellate cell

    KW - basic helix-loop-helix transcription factors

    KW - MyoD

    KW - Id1

    KW - FAT-STORING CELLS

    KW - KAPPA-B-FAMILY

    KW - TISSUE INHIBITOR

    KW - GENE-EXPRESSION

    KW - HLH PROTEINS

    KW - ID PROTEINS

    KW - ITO-CELLS

    KW - FIBROSIS

    KW - LIVER

    KW - MYOD

    U2 - 10.1136/gut.49.5.713

    DO - 10.1136/gut.49.5.713

    M3 - Article

    VL - 5

    SP - 713

    EP - 717

    JO - Gut

    JF - Gut

    SN - 0017-5749

    ER -