title: Activation of host tissue trophic factors through JAK-STAT3 signaling: a mechanism of mesenchymal stem cell-mediated cardiac repair.
abstract: We recently demonstrated a cardiac therapeutic regimen based on injection of bone marrow mesenchymal stem cells (MSCs) into the skeletal muscle. Although the injected MSCs were trapped in the local musculature, the extracardiac cell delivery approach repaired the failing hamster heart. This finding uncovers a tissue repair mechanism mediated by trophic factors derived from the injected MSCs and local musculature that can be explored for minimally invasive stem cell therapy. However, the trophic factors involved in cardiac repair and their actions remain largely undefined. We demonstrate here a role of MSC-derived IL-6-type cytokines in cardiac repair through engagement of the skeletal muscle JAK-STAT3 axis. The MSC IL-6-type cytokines activated JAK-STAT3 signaling in cultured C2C12 skeletal myocytes and caused increased expression of the STAT3 target genes hepatocyte growth factor (HGF) and VEGF, which was inhibited by glycoprotein 130 (gp130) blockade. These in vitro findings were corroborated by in vivo studies, showing that the MSC-injected hamstrings exhibited activated JAK-STAT3 signaling and increased growth factor/cytokine production. Elevated host tissue growth factor levels were also detected in quadriceps, liver, and brain, suggesting a possible global trophic effect. Paracrine actions of these host tissue-derived factors activated the endogenous cardiac repair mechanisms in the diseased heart mediated by Akt, ERK, and JAK-STAT3. Administration of the cell-permeable JAK-STAT inhibitor WP1066 abrogated MSC-mediated host tissue growth factor expression and functional improvement. The study illustrates that the host tissue trophic factor network can be activated by MSC-mediated JAK-STAT3 signaling for tissue repair.
authors.affiliation: Department of Biochemistry and Center for Research in Cardiovascular Medicine, University at Buffalo, New York 14214, USA.
authors.forename: Arsalan
authors.initials: A
authors.lastname: Shabbir
authors.forename: David
authors.initials: D
authors.lastname: Zisa
authors.forename: Huey
authors.initials: H
authors.lastname: Lin
authors.forename: Michalis
authors.initials: M
authors.lastname: Mastri
authors.forename: Gregory
authors.initials: G
authors.lastname: Roloff
authors.forename: Gen
authors.initials: G
authors.lastname: Suzuki
authors.forename: Techung
authors.initials: T
authors.lastname: Lee
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D006224:Cricetinae; D016207:Cytokines / Q000378:metabolism; D017228:Hepatocyte Growth Factor / Q000378:metabolism*; D053612:Janus Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D008297:Male; D045164:Mesenchymal Stem Cell Transplantation; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000378:metabolism*; D023421:Models, Animal; D018485:Muscle Fibers, Skeletal / Q000166:cytology / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism; D011725:Pyridines / Q000494:pharmacology; D050796:STAT3 Transcription Factor / Q000037:antagonists & inhibitors / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*; D020032:Tyrphostins / Q000494:pharmacology; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism*
chemical_list: D016207:Cytokines; D011725:Pyridines; D050796:STAT3 Transcription Factor; D020032:Tyrphostins; D042461:Vascular Endothelial Growth Factor A; C519885:WP1066; D017228:Hepatocyte Growth Factor; D053612:Janus Kinases