Cellular uptake of stearic, oleic, linoleic, and linolenic acid and their effects on synthesis and secretion of lipids in Hep-G2 cells

• Published in: The international journal of biochemistry & cell biology 1998-01, Vol.30 (1), p.65-76
• Main Authors: Dokko, Ryowon Choue, Cho, B.H.Simon, Chung, Byung Hong
• Format: Article
• Language: English
• Subjects: Acetates - chemistry; Acetates - metabolism; alpha-Linolenic Acid - metabolism; alpha-Linolenic Acid - pharmacology; Carcinoma, Hepatocellular - metabolism; Cell Division - drug effects; Cell Survival - drug effects; Cholesterol; Cholesterol - biosynthesis; Chromatography, Thin Layer; Fatty acid uptake; Fatty Acids - chemistry; Fatty Acids - metabolism; Glycerol - metabolism; Hep-G2 cell; Humans; Linoleic Acid - metabolism; Linoleic Acid - pharmacology; Lipoprotein-lipid secretion; Liver - metabolism; Liver Neoplasms - metabolism; Oleic Acid - metabolism; Oleic Acid - pharmacology; Phospholipid; Phospholipids - biosynthesis; Stearic Acids - metabolism; Stearic Acids - pharmacology; Triglyceride; Triglycerides - biosynthesis; Tumor Cells, Cultured - drug effects; Tumor Cells, Cultured - metabolism
• ISSN: 1357-2725; 1878-5875
• DOI: 10.1016/S1357-2725(97)00097-6

The present study was undertaken to examine the cellular uptake of stearic (18:0), oleic (18:1), linoleic (18:2), and linolenic acid (18:3), and their effects on synthesis and secretion of lipids in Hep-G2 cells. The cells were grown for 6 days in Dulbecco's modified Eagle's medium (DMEM) supplemented with 10% fetal bovine serum. On day 7, cells were incubated in a serum-free DMEM containing 0.25–1.0 mM of 18:0, 18:1, 18:2 or 18:3. The cellular uptake of these fatty acids was almost linear during the 4 hr incubation period, and no significant differences were noted among the fatty acids tested, regardless of their degree of unsaturation. The treatment of cells with 1.0 mM of these fatty acids stimulated triglyceride (TG) synthesis nearly ten-fold and phospholipid (PL) synthesis approx. two-fold compared with those of the control. The lipoprotein-TG secretion also increased and was the highest with 18:1 followed in descending order by 18:2, 18:3, and 18:0. The fatty acid treatment of cells also significantly increased the incorporation of 14C-acetate into the cellular and lipoprotein cholesterol compared with that of the control ( p