Document Detail


Hypercholesterolemia is associated with hyperactive cardiac mTORC1 and mTORC2 signaling.
MedLine Citation:
PMID:  19395857     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Nutritional excess and hyperlipidemia increase the heart's susceptibility to ischemic injury. Mammalian target of rapamycin (mTOR) controls the cellular response to nutritional status and may play a role in ischemic injury. To explore the effect of hypercholesterolemia on cardiac mTOR signaling, we assessed mTOR signaling in hypercholesterolemic swine (HC) that are also susceptible to increased cardiac ischemia-reperfusion injury. Yucatan pigs were fed a high-fat/high-cholesterol diet for 4 weeks to induce hypercholesterolemia, and mTOR signaling was measured by immunoblotting and immunofluorescence in the non-ischemic left ventricular area. Total myocardial mTOR and raptor levels were markedly increased in the HC group compared to the normocholesterolemic group, and directly correlated with serum cholesterol levels. mTOR exhibited intense perinuclear staining in myocytes only in the HC group. Hypercholesterolemia was associated with hyperactive signaling upstream and downstream of both mTOR complexes, including myocardial Akt, S6K1, 4EBP1, S6 and PKC-alpha, increased levels of cardiac hypertrophy markers, and a trend toward lower levels of myocardial autophagy. Hypercholesterolemia can now be added to the growing list of conditions associated with aberrant mTOR signaling. Hypercholesterolemia produces a unique profile of alterations in cardiac mTOR signaling, which is a potential target in cardiac diseases associated with hypercholesterolemia and nutritional excess.
Authors:
Hilary P Glazer; Robert M Osipov; Richard T Clements; Frank W Sellke; Cesario Bianchi
Related Documents :
12768597 - Mapping ischemic risk region and necrosis in the isolated heart using epr imaging.
16040717 - Cardioprotection induced by cardiac-specific overexpression of fibroblast growth factor...
20353807 - The effects of ginseng total saponin, panaxadiol and panaxatriol on ischemia/reperfusio...
22292457 - Type of desmin expression in cardiomyocytes -a good marker of heart failure development...
12380767 - Cumulative effect of preceding pacing cycle length on ventricular repolarization after ...
18426377 - Increased adherence to cardiac standards of care during participation in cardiac diseas...
Publication Detail:
Type:  Journal Article; Research Support, N.I.H., Extramural; Research Support, Non-U.S. Gov't     Date:  2009-06-03
Journal Detail:
Title:  Cell cycle (Georgetown, Tex.)     Volume:  8     ISSN:  1551-4005     ISO Abbreviation:  Cell Cycle     Publication Date:  2009 Jun 
Date Detail:
Created Date:  2009-05-18     Completed Date:  2009-07-28     Revised Date:  2013-06-02    
Medline Journal Info:
Nlm Unique ID:  101137841     Medline TA:  Cell Cycle     Country:  United States    
Other Details:
Languages:  eng     Pagination:  1738-46     Citation Subset:  IM    
Affiliation:
Division of Cardiothoracic Surgery Research, Beth Israel Deaconess Medical Center & Harvard Medical School, Boston, MA 02215, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Dietary Fats / administration & dosage
Eukaryotic Initiation Factors / metabolism
Hypercholesterolemia / enzymology,  metabolism*
Male
Myocytes, Cardiac / metabolism*
Protein Kinase C-alpha / metabolism
Protein Kinases / metabolism*
Proto-Oncogene Proteins c-akt / metabolism
Ribosomal Protein S6 / metabolism
Ribosomal Protein S6 Kinases, 70-kDa / metabolism
Signal Transduction
Swine
TOR Serine-Threonine Kinases
Transcription Factors / metabolism*
Grant Support
ID/Acronym/Agency:
HL076130/HL/NHLBI NIH HHS; HL46716/HL/NHLBI NIH HHS; HL69024/HL/NHLBI NIH HHS; R01 HL046716-08/HL/NHLBI NIH HHS; R01 HL069024-05/HL/NHLBI NIH HHS; R01 HL069024-09/HL/NHLBI NIH HHS
Chemical
Reg. No./Substance:
0/Dietary Fats; 0/Eukaryotic Initiation Factors; 0/Ribosomal Protein S6; 0/Transcription Factors; EC 2.7.-/Protein Kinases; EC 2.7.1.1/TOR Serine-Threonine Kinases; EC 2.7.11.1/Proto-Oncogene Proteins c-akt; EC 2.7.11.1/Ribosomal Protein S6 Kinases, 70-kDa; EC 2.7.11.1/ribosomal protein S6 kinase, 70kD, polypeptide 1; EC 2.7.11.13/Protein Kinase C-alpha
Comments/Corrections
Comment In:
Cell Cycle. 2009 Jun 1;8(11):1646   [PMID:  19454842 ]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  NFATc2 Ser170 phosphorylation marks mitosis in development and ES cells.
Next Document:  ERK activation increases nitroprusside induced apoptosis in human melanoma cells irrespective of p53...