The effects of unsaturated fatty acids on lipid metabolism in HepG2 cells.
We investigated the effects of stearic acid (saturated), oleic acid (monounsaturated), linoleic acid (n-6 polyunsaturated), and alpha-linolenic acid (n-3 polyunsaturated) on lipid metabolism in a hepatocyte-derived cell line, HepG2. HepG2 cells were cultured in medium supplemented with either stearic acid (0.1% w/v), oleic acid (0.1% v/v), linoleic acid (0.1% v/v), or alpha-linolenic acid (0.1% v/v). After 24 h, expression of lipid metabolism-associated genes was evaluated by real-time PCR. Alpha-linolenic acid showed a suppressive effect on the hepatic fatty acid de novo synthesis and fatty acid oxidation pathways, while linoleic acid also showed a tendency to suppress these pathways although the effect was weaker. Moreover, alpha-linolenic acid enhanced the expression of enzymes associated with reactive oxygen species (ROS) elimination. In contrast, oleic acid tended to promote fatty acid synthesis and oxidation. In conclusion, alpha-linolenic acid and linoleic acid may be expected to ameliorate hepatic steatosis by downregulating fatty acid de novo synthesis and fatty acid oxidation, and by upregulating ROS elimination enzymes. Oleic acid had no distinct effects for improving steatosis or oxidative stress.
Kohjima
Motoyuki
M
Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan.
Enjoji
Munechika
M
Higuchi
Nobito
N
Kato
Masaki
M
Kotoh
Kazuhiro
K
Nakashima
Manabu
M
Nakamuta
Makoto
M
D002460:Cell Line; D005231:Fatty Acids, Unsaturated / Q000378:metabolism / Q000494:pharmacology*; D022781:Hepatocytes / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D008041:Linoleic Acids / Q000378:metabolism / Q000494:pharmacology; D050356:Lipid Metabolism / Q000187:drug effects*; D019301:Oleic Acid / Q000494:pharmacology; D014407:Tumor Cells, Cultured
D005231:Fatty Acids, Unsaturated; D008041:Linoleic Acids; D019301:Oleic Acid