Linked Life Data

20974050

Source:http://linkedlifedata.com/resource/pubmed/id/20974050

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2010-10-26
pubmed:abstractText
This study was designed to test the role of liver lipases in the degradation of liver triacylglycerols (TAG) and to determine the effect of dietary induced TAG accumulation in the liver on regulation of their lipolysis. Male Wistar rats were administered high-fat or high-sucrose diet for two weeks. Individual lipases (HL; TGH; LAL) were identified according to their different pH optimum. Administration of both diets resulted in liver TAG accumulation (HFD >>> HSD). The only lipase capable to hydrolyse intracellular TAG was LAL. On standard diet, LAL activity towards both endogenous and exogenous substrates was up-regulated in fasting and downregulated in fed state. The intensity of autophagy determined according to the LC3-II/LC3-I protein ratio followed a similar pattern. HFD led to an increase of this ratio, elevation of LAL activity in phagolysosomal fraction and abolishment of fasting/fed-dependent differences. LAL activity significantly correlated with ketogenesis in all groups (r = 0.86; P < 0.01). In the HFD group, we determined the enhanced release of lysosomal enzymes (glucuronidase, LAL) into the cytosol. Dgat-1 expression was up-regulated in HFD- and HSD-fed groups, which indicates increased FFA esterification. We demonstrated that LAL is a dominant enzyme involved in degradation of intracellular TAG in the liver and its translocation into the fraction of active (auto)phagolysosomes is stimulated by diet-induced TAG accumulation. Autophagy is stimulated under the same conditions as LAL and may represent the mechanism ensuring the substrate enzyme contact in autophagolysosomes. In fatty liver, destabilization of (auto)phagolysosomes may contribute to their susceptibility to further stress factors.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0015-5500
pubmed:author
pubmed:issnType
Print
pubmed:volume
56
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
173-82
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
The autophagy-lysosomal pathway is involved in TAG degradation in the liver: the effect of high-sucrose and high-fat diet.
pubmed:affiliation
Department of Metabolism and Diabetes, Centre of Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic. monika.cahova@ikem.cz
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't