PI3K/Akt activation is critical for early hepatic regeneration after partial hepatectomy

dc.contributor.advisorB. Mark Evers, M.D.en_US
dc.contributor.committeeMemberSundararajah Thevananther, Ph.D.en_US
dc.contributor.committeeMemberKathleen O'Connor, Ph.D.en_US
dc.contributor.committeeMemberFrank C. Schmalstieg, M.D., Ph.D.en_US
dc.contributor.committeeMemberCornelis Elferink, Ph.D.en_US
dc.creatorLindsey Nicole Jackson, M.D.en_US
dc.date.accessioned2011-12-20T16:05:17Z
dc.date.accessioned2014-02-19T22:05:33Z
dc.date.available2008-12-10en_US
dc.date.available2011-12-20T16:05:17Z
dc.date.available2014-02-19T22:05:33Z
dc.date.created2008-08-26en_US
dc.date.issued2008-11-25en_US
dc.description.abstractHepatic resection is associated with rapid proliferation and regeneration of the remnant liver. Phosphatidylinositol 3-kinase (PI3K), composed of a p85Ą regulatory and a p110Ą catalytic subunit, participates in multiple cellular processes, including cell growth and survival; however, the role of PI3K in liver regeneration has not been clearly delineated. In these studies, we used the potent PI3K inhibitor, wortmannin, and small-interfering RNA (siRNA) targeting the p85Ą and p110Ą subunits to determine if total or selective PI3K inhibition would abrogate the proliferative response of the liver following resection. After partial hepatectomy in mice, there is an increase in PI3K activity; total PI3K blockade with wortmannin, and selective inhibition of p85Ą or p110Ą with siRNA resulted in a significant decrease in hepatocyte proliferation, especially at the earliest timepoints (ie, 48h and 72h). Fewer macrophages and Kupffer cells were present in the regenerating liver of mice treated with wortmannin or siRNA to p85Ą or p110Ą, as reflected by a paucity of F4/80+ cells present by immunohistochemistry (IHC). Additionally, PI3K inhibition led to an aberrant hepatocyte architecture characterized by vacuolization, lipid deposition, and glycogen accumulation. Our data demonstrate that PI3K/Akt pathway activation plays a critical role in the early regenerative response of the liver after resection; inhibition of this pathway markedly abrogates the normal hepatic regenerative response, perhaps by inhibiting macrophage infiltration and cytokine elaboration and thus hepatocyte priming for replication.en_US
dc.format.mediumelectronicen_US
dc.identifier.otheretd-08262008-144022en_US
dc.identifier.urihttp://hdl.handle.net/2152.3/220
dc.language.isoengen_US
dc.rightsCopyright © is held by the author. Presentation of this material on the TDL web site by The University of Texas Medical Branch at Galveston was made possible under a limited license grant from the author who has retained all copyrights in the works.en_US
dc.subjectphosphatidylinositol 3-kinaseen_US
dc.subjectp85-alphaen_US
dc.subjectp110-alphaen_US
dc.subjectliver regenerationen_US
dc.subjecthepatectomyen_US
dc.titlePI3K/Akt activation is critical for early hepatic regeneration after partial hepatectomyen_US
dc.type.genredissertationen_US
dc.type.materialtexten_US
thesis.degree.departmentCell Biologyen_US
thesis.degree.grantorThe University of Texas Medical Branchen_US
thesis.degree.levelDoctoralen_US
thesis.degree.namePhDen_US

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