Fucoxanthin Enhances Chain Elongation and Desaturation of Alpha-Linolenic Acid in HepG2 Cells
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Dietary fucoxanthin (FX), a carotenoid compound from brown algae, was found to increase docosahexaenoic acid (DHA, 22:6n-3) and arachidonic acid (ARA, 20:4n-6) in the liver of mice. DHA and ARA are known to be biosynthesized from the respective precursor α-linolenic acid (ALA, 18:3n-3) and linoleic acid (LNA, 18:2n-6), through desaturation and chain elongation. We examined the effect of FX on the fatty acid metabolism in HepG2 cells (Hepatocellular carcinoma, human). In the first experiment, cells were co-treated with ALA (100 μM) and FX (0–100 μM) or vehicle for 48 h. FX increased eicosapentaenoic acid (EPA, 20:5n-3), docosapentaenoic acid (DPA, 22:5n-3), DHA at concentrations of ≥50 μM. To clarify the change in the metabolism of polyunsaturated fatty acid (PUFA), in the second experiment, cells were co-treated with universally-[13C]-labeled (U-[13C]-) ALA (100 μM) and FX (100 μM) for 0.5, 3, 6, 24 and 48 h. [13C] labeled-EPA, DPA and DHA content in HepG2 cells were all increased by FX after 48 h treatment. Furthermore, estimated delta-5 desaturase (D5D) but not delta-6 desaturase (D6D) activity index was increased at 48 h. These results suggested that FX may enhance the conversion of ALA to longer chain n-3 PUFA through increasing D5D activity in the liver.
KeywordsFucoxanthin Delta-5 desaturase Elongation ALA EPA DHA n-3 PUFA
Bovine serum albumin
Fatty acid methyl ester
Fetal bovine serum
Liver X receptor α
Monounsaturated fatty acid
Peroxisome proliferator-activated receptor α
Polyunsaturated fatty acid
Stearoyl-CoA desaturase 1
Sterol regulatory element binding protein
This study was supported by a grant from the National Science Council of Taiwan (NSC 99-2313-B-002-013-MY3 and NSC 98-2313-B-002-002-MY3).
Compliance with Ethical Standards
Conflict of interest
The authors declare no conflict of interest.
- 7.Kroger J, Zietemann V, Enzenbach C, Weikert C, Jansen EH, Doring F, Joost HG, Boeing H, Schulze MB (2011) Erythrocyte membrane phospholipid fatty acids, desaturase activity, and dietary fatty acids in relation to risk of type 2 diabetes in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam Study. Am J Clin Nutr 93:127–142CrossRefPubMedGoogle Scholar
- 20.Cui Y, Fraser C, Gardner G, Huang CJ, Reith M, Windust AJ (2012) Isolation and optimisation of the oleaginous yeast Sporobolomyces roseus for biosynthesis of 13C isotopically labelled 18-carbon unsaturated fatty acids and trans 18:1 and 18:2 derivatives through synthesis. J Ind Microbiol Biotechnol 39:153–161CrossRefPubMedGoogle Scholar
- 24.Matsuzaka T, Shimano H, Yahagi N, Amemiya-Kudo M, Yoshikawa T, Hasty AH, Tamura Y, Osuga J, Okazaki H, Iizuka Y, Takahashi A, Sone H, Gotoda T, Ishibashi S, Yamada N (2002) Dual regulation of mouse Delta(5)- and Delta(6)-desaturase gene expression by SREBP-1 and PPARalpha. J Lipid Res 43:107–114PubMedGoogle Scholar