Linked Life Data

17761767

Source:http://linkedlifedata.com/resource/pubmed/id/17761767

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
2007-11-16
pubmed:abstractText
Illnesses associated with insulin resistance exhibit increases in whole-body protein degradation and amino acid oxidation. However, the mechanisms stimulating muscle catabolism under these conditions are not clear. Because insulin resistance is associated with accumulation of lipids in muscle, we measured protein degradation in muscles of mice fed a high-fat diet. Muscle protein catabolism was accelerated on the high-fat diet, and this was associated with an increase in plasma free fatty acid and a decrease in plasma levels of the adipocyte-derived cytokine adiponectin. To evaluate how free fatty acids influence adiponectin-mediated changes in muscle protein breakdown we examined C2C12 skeletal muscle cells exposed to free fatty acids. Both saturated fatty acids (palmitate) and unsaturated fatty acids (oleate) increased protein degradation (25 and 18%, respectively) in part by activating the E3 ubiquitin ligases. Adenovirus-mediated overexpression of adiponectin blocked fatty acid-induced protein degradation in C2C12 cells. Palmitate activated the E3 ubiquitin ligases by suppressing insulin receptor substrate-1/Akt signaling in the C2C12 muscle cells, whereas adiponectin attenuated the E3 ubiquitin ligase activation by increasing both insulin receptor substrate-1 tyrosine phosphorylation and Akt Ser473 phosphorylation. In related experiments, adiponectin overexpression decreased TNFalpha and IL-6 expression in 3T3-L1 adipocytes, whereas exposure to free fatty acids had the opposite effect. We conclude that the balance between free fatty acids and adiponectin impacts muscle proteolysis in insulin-resistant conditions and suggest a role for adipose tissue-muscle cross talk in diabetes and obesity.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0013-7227
pubmed:author
pubmed:issnType
Print
pubmed:volume
148
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5696-705
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:17761767-3T3-L1 Cells, pubmed-meshheading:17761767-Adiponectin, pubmed-meshheading:17761767-Adipose Tissue, pubmed-meshheading:17761767-Animals, pubmed-meshheading:17761767-Blotting, Northern, pubmed-meshheading:17761767-Blotting, Western, pubmed-meshheading:17761767-Body Weight, pubmed-meshheading:17761767-Cell Line, pubmed-meshheading:17761767-Cells, Cultured, pubmed-meshheading:17761767-Cytokines, pubmed-meshheading:17761767-Dietary Fats, pubmed-meshheading:17761767-Fatty Acids, Nonesterified, pubmed-meshheading:17761767-Forkhead Transcription Factors, pubmed-meshheading:17761767-Immunoprecipitation, pubmed-meshheading:17761767-Insulin Resistance, pubmed-meshheading:17761767-Mice, pubmed-meshheading:17761767-Mice, Inbred C57BL, pubmed-meshheading:17761767-Muscle Proteins, pubmed-meshheading:17761767-Muscles, pubmed-meshheading:17761767-Phosphorylation, pubmed-meshheading:17761767-Proto-Oncogene Proteins c-akt, pubmed-meshheading:17761767-Reverse Transcriptase Polymerase Chain Reaction, pubmed-meshheading:17761767-Signal Transduction, pubmed-meshheading:17761767-Ubiquitin-Protein Ligases
pubmed:year
2007
pubmed:articleTitle
Evidence for adipose-muscle cross talk: opposing regulation of muscle proteolysis by adiponectin and Fatty acids.
pubmed:affiliation
Renal Division, Department of Medicine, Emory University School of Medicine, 1639 Pierce Drive, WMB 338, Atlanta, GA 30322, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural