Changes in mRNA levels of intracellular fatty acid metabolism regulators in human hepatoma HepG2 cells following their treatment with non-esterified fatty acids and dehydroepiandrosterone.
The effects of non-esterified fatty acids (NEFA) and hormone dehydroepiandrosterone (DHEA) on the levels of mRNAs of protein kinase C (PKC) -delta and -epsilon isoforms and those of liver fatty acid binding protein (L-FABP) were investigated in the human hepatoma HepG2 cell line. The cells were kept in low-serum, low-albumin medium during experiments. Low FA levels (100 microM) and time intervals of 4 h and 20 h were used. In these conditions, the saturated (palmitic, stearic) and monounsaturated (oleic) acids rather selectively stimulated PKC-epsilon mRNA levels. Unexpectedly, we found that these acids also suppressed liver fatty-acid binding protein (L-FABP) mRNA levels. DHEA in pharmacological doses (100 microM) produced a significant increase in PKC-delta and -epsilon mRNA levels. Although molecular mechanisms underlying the identified changes have not been investigated in this paper, our findings emphasize that NEFA-induced modulation of mRNA levels of key signalling components represent an additional mechanism for how the ambient NEFA can influence metabolic homeostasis in cells.
Rypka
Miroslav
M
Department of Pathological Physiology, Palacký University, Olomouc, Czech Republic. mirek@tunw.upol.cz
Cervenková
Katerina
K
Uherková
Lenka
L
Poczatková
Hana
H
Bogdanová
Katerina
K
Veselý
Jaroslav
J
D006528:Carcinoma, Hepatocellular / Q000378:metabolism; D045744:Cell Line, Tumor; D003687:Dehydroepiandrosterone / Q000494:pharmacology*; D050556:Fatty Acid-Binding Proteins / Q000235:genetics / Q000378:metabolism; D005230:Fatty Acids, Nonesterified / Q000494:pharmacology*; D006801:Humans; D008099:Liver / Q000378:metabolism*; D008113:Liver Neoplasms / Q000378:metabolism; D011493:Protein Kinase C / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism*
D050556:Fatty Acid-Binding Proteins; D005230:Fatty Acids, Nonesterified; D012333:RNA, Messenger; D003687:Dehydroepiandrosterone; D011493:Protein Kinase C