Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2005-8-15
pubmed:abstractText
Recently, adipose triglyceride lipase (ATGL, also called desnutrin and calcium-independent phospholipase A2 [iPLA(2)] zeta) was isolated as a novel adipose-expressed triglyceride lipase which is downregulated in obesity and may contribute to obesity-associated metabolic disorders such as hyperlipidemia and insulin resistance. To clarify expression and regulation of this fat-derived lipase, ATGL mRNA was measured in 3T3-L1 adipocytes by quantitative real-time reverse transcription-polymerase chain reaction after treatment with isoproterenol, tumor necrosis factor (TNF) alpha, insulin, and growth hormone (GH) which have been shown to influence lipolysis and insulin sensitivity profoundly. Interestingly, treatment of adipocytes with 100 nM isoproterenol, 30 ng/ml TNF alpha, and 100 nM insulin for 16 h significantly decreased ATGL mRNA to 74%, 17%, and 49% of control levels, respectively. GH did not influence ATGL synthesis. The effect of isoproterenol, TNFalpha, and insulin on ATGL expression was time- and dose-dependent. Similarly, HSL mRNA was downregulated by the three hormones. Furthermore, signaling studies suggested that activation of Gs-protein-coupled pathways by forskolin and cholera toxin is sufficient to significantly downregulate ATGL mRNA. Moreover, p44/42 mitogen-activated protein kinase appears to partly mediate the negative effect of insulin but not TNFalpha on ATGL. Taken together, downregulation of ATGL by isoproterenol, TNFalpha, and insulin might contribute to dysregulated expression and function of this lipase in obesity, hyperlipidemia, and insulin resistance.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0303-7207
pubmed:author
pubmed:issnType
Print
pubmed:day
30
pubmed:volume
240
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
43-9
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Isoproterenol, TNFalpha, and insulin downregulate adipose triglyceride lipase in 3T3-L1 adipocytes.
pubmed:affiliation
University of Leipzig, Department of Internal Medicine III, Leipzig, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't