Effects of individual and multiple fatty acids (palmitate, oleate and docosahaexenoic acid) on cell viability and lipid metabolism in LO2 human liver cells

Chen,Li; Wang,Chunhong; Huang,Shaoxin; Gong,Bin; Yu,Jun; Shi,Qun; Chen,Guoxun

doi:10.3892/mmr.2014.2579

Effects of individual and multiple fatty acids (palmitate, oleate and docosahaexenoic acid) on cell viability and lipid metabolism in LO2 human liver cells

Authors:
- Li Chen
- Chunhong Wang
- Shaoxin Huang
- Bin Gong
- Jun Yu
- Qun Shi
- Guoxun Chen
View Affiliations

Affiliations: Department of Toxicology, School of Public Health, Wuhan University, Wuhan, Hubei 430071, P.R. China, Department of Nutrition, The University of Tennessee at Knoxville, Knoxville, TN 37996, USA
Published online on: September 18, 2014 https://doi.org/10.3892/mmr.2014.2579
Pages: 3254-3260

Metrics: Total Views: 0 (Spandidos Publications: | PMC Statistics: )

Metrics: Total PDF Downloads: 0 (Spandidos Publications: | PMC Statistics: )

Cited By (CrossRef): 0 citations Loading Articles...

Abstract

This study was designed to investigate the direct effects of fatty acids (FAs) on the cell viability and the expression levels of genes involved in lipid metabolism in LO2 human liver cells. Palmitate (PA), oleate (OA) and docosahaexenoic acid (DHA) were used to represent saturated, mono-unsaturated and polyunsaturated FAs, respectively. At concentrations of ≤3.2 µg/ml, treatment with single FAs increased the viability of the LO2 cells. At FA concentrations of >3.2 µg/ml, cell viability following OA treatment was increased, but PA or DHA treatment at these concentrations reduced cell viability. Administration of mixtures of these FAs in three ratios (PA:OA:DHA = 1:2:1, 1:1:1 and 1:1:2, respectively) increased the cell viability compared with the control group. The intracellular triglyceride (TG) levels following all types of treatment were significantly increased and the accumulation of TGs was markedly increased with high doses of DHA. In addition, peroxisome proliferator-activated receptor-γ was significantly upregulated in all groups, with the exception of the 1:1:1 group at 3.2 µg/ml and the 1:1:2 group at 12.8 µg/ml. The expression levels of sterol regulatory-element binding protein‑1c, liver X receptor α and apolipoprotein C‑I were significantly reduced in all groups with the exception of the DHA‑treated group and the 1:2:1 groups at 3.2 and 12.8 µg/ml. In conclusion, these results indicate that the type, concentration and mixture ratios of FAs are all important in determining the cell viability and lipid metabolism-related gene expression in LO2 hepatocytes.

View Figures

View References

1	Dietschy JM: Dietary fatty acids and the regulation of plasma low density lipoprotein cholesterol concentrations. J Nutr. 128:444S–448S. 1998.PubMed/NCBI
2	Videla LA, Rodrigo R, Araya J and Poniachik J: Insulin resistance and oxidative stress interdependency in non-alcoholic fatty liver disease. Trends Mol Med. 12:555–558. 2006. View Article : Google Scholar : PubMed/NCBI
3	Aronis A, Madar Z and Tirosh O: Mechanism underlying oxidative stress-mediated lipotoxicity: exposure of J774.2 macrophages to triacylglycerols facilitates mitochondrial reactive oxygen species production and cellular necrosis. Free Radic Biol Med. 38:1221–1230. 2005. View Article : Google Scholar
4	McGarry JD: Banting lecture 2001: dysregulation of fatty acid metabolism in the etiology of type 2 diabetes. Diabetes. 51:7–18. 2002. View Article : Google Scholar : PubMed/NCBI
5	Zhang Y, Li R, Li Y, Chen W, Zhao S and Chen G: Vitamin A status affects obesity development and hepatic expression of key genes for fuel metabolism in Zucker fatty rats. Biochem Cell Biol. 90:548–557. 2012. View Article : Google Scholar : PubMed/NCBI
6	Chawla A, Repa JJ, Evans RM and Mangelsdorf DJ: Nuclear receptors and lipid physiology: opening the X-files. Science. 294:1866–1870. 2001. View Article : Google Scholar : PubMed/NCBI
7	Clarke SD: The multi-dimensional regulation of gene expression by fatty acids: polyunsaturated fats as nutrient sensors. Curr Opin Lipidol. 15:13–18. 2004. View Article : Google Scholar : PubMed/NCBI
8	Jump DB, Botolin D, Wang Y, Xu J, Christian B and Demeure O: Fatty acid regulation of hepatic gene transcription. J Nutr. 135:2503–2506. 2005.PubMed/NCBI
9	Jump DB: N-3 polyunsaturated fatty acid regulation of hepatic gene transcription. Curr Opin Lipidol. 19:242–247. 2008. View Article : Google Scholar : PubMed/NCBI
10	Boelsterli UA and Bedoucha M: Toxicological consequences of altered peroxisome proliferator-activated receptor gamma (PPARgamma) expression in the liver: insights from models of obesity and type 2 diabetes. Biochem Pharmacol. 63:1–10. 2002. View Article : Google Scholar
11	Schultz JR, Tu H, Luk A, et al: Role of LXRs in control of lipogenesis. Genes Dev. 14:2831–2838. 2000. View Article : Google Scholar : PubMed/NCBI
12	Repa JJ, Turley SD, Lobaccaro JA, et al: Regulation of absorption and ABC1-mediated efflux of cholesterol by RXR heterodimers. Science. 289:1524–1529. 2000. View Article : Google Scholar : PubMed/NCBI
13	Jong MC, Voshol PJ, Muurling M, et al: Protection from obesity and insulin resistance in mice overexpressing human apolipoprotein C1. Diabetes. 50:2779–2785. 2001. View Article : Google Scholar : PubMed/NCBI
14	Galetto R, Albajar M, Polanco JI, Zakin MM and Rodriguez-Rey JC: Identification of a peroxisome-proliferator-activated-receptor response element in the apolipoprotein E gene control region. Biochem J. 357:521–527. 2001. View Article : Google Scholar : PubMed/NCBI
15	Clarke SD and Jump DB: Dietary polyunsaturated fatty acid regulation of gene transcription. Annual review of nutr. 14:83–98. 1994. View Article : Google Scholar : PubMed/NCBI
16	Jump DB, Thelen A and Mater M: Dietary polyunsaturated fatty acids and hepatic gene expression. Lipids. 34:S209–S212. 1999. View Article : Google Scholar : PubMed/NCBI
17	Sampath H and Ntambi JM: Regulation of gene expression by polyunsaturated fatty acids. Heart Metab. 32:32–35. 2006.
18	Pan XF, Wen CX and Xu JH: Comparison of two cell lines for cell model of hepatocytic steatosis in vitro. Journal of Guangdong Pharmaceutical College. 1:0422010.
19	Yang X, Zhang Y, Lin J, et al: A lower proportion of dietary saturated/monounsaturated/polyunsaturated fatty acids reduces the expression of adiponectin in rats fed a high-fat diet. Nutr Res. 32:285–291. 2012. View Article : Google Scholar
20	Di Nunzio M, Valli V and Bordoni A: Pro- and anti-oxidant effects of polyunsaturated fatty acid supplementation in HepG2 cells. Prostaglandins, Leukot Essent Fatty Acids. 85:121–127. 2011.PubMed/NCBI
21	Ricchi M, Odoardi MR, Carulli L, et al: Differential effect of oleic and palmitic acid on lipid accumulation and apoptosis in cultured hepatocytes. J Gastroenterol Hepatol. 24:830–840. 2009. View Article : Google Scholar : PubMed/NCBI
22	Wong SH, Fisher EA and Marsh JB: Effects of eicosapentaenoic and docosahexaenoic acids on apoprotein B mRNA and secretion of very low density lipoprotein in HepG2 cells. Arteriosclerosis. 9:836–841. 1989. View Article : Google Scholar : PubMed/NCBI
23	Vidal-Puig A, Jimenez-Liñan M, Lowell BB, et al: Regulation of PPAR gamma gene expression by nutrition and obesity in rodents. J Clin Invest. 97:2553–2561. 1996. View Article : Google Scholar : PubMed/NCBI
24	Knight BL, Hebbachi A, Hauton D, et al: A role for PPARalpha in the control of SREBP activity and lipid synthesis in the liver. Biochem J. 389:413–421. 2005. View Article : Google Scholar : PubMed/NCBI
25	Patel DD, Knight BL, Wiggins D, Humphreys SM and Gibbons GF: Disturbances in the normal regulation of SREBP-sensitive genes in PPAR alpha-deficient mice. J Lipid Res. 42:328–337. 2001.PubMed/NCBI
26	Bensinger SJ and Tontonoz P: Integration of metabolism and inflammation by lipid-activated nuclear receptors. Nature. 454:470–477. 2008. View Article : Google Scholar : PubMed/NCBI
27	Wójcicka G, Jamroz-Wiśniewska A, Horoszewicz K and Bełtowski J: Liver X receptors (LXRs). Part I: structure, function, regulation of activity, and role in lipid metabolism. Postepy Hig Med Dosw (Online). 61:736–759. 2007.PubMed/NCBI
28	Laffitte BA, Joseph SB, Walczak R, et al: Autoregulation of the human liver X receptor alpha promoter. Mol Cell Biol. 21:7558–7568. 2001. View Article : Google Scholar : PubMed/NCBI
29	Tobin KA, Steineger HH, Alberti S, et al: Cross-talk between fatty acid and cholesterol metabolism mediated by liver X receptor-alpha. Mol Endocrinol. 14:741–752. 2000.PubMed/NCBI
30	Horton JD, Goldstein JL and Brown MS: SREBPs: activators of the complete program of cholesterol and fatty acid synthesis in the liver. J Clin Invest. 109:1125–1131. 2002. View Article : Google Scholar : PubMed/NCBI
31	Xu J, Nakamura MT, Cho HP and Clarke SD: Sterol regulatory element binding protein-1 expression is suppressed by dietary polyunsaturated fatty acids. A mechanism for the coordinate suppression of lipogenic genes by polyunsaturated fats. J Biol Chem. 274:23577–23583. 1999. View Article : Google Scholar
32	Pettinelli P and Videla LA: Up-regulation of PPAR-gamma mRNA expression in the liver of obese patients: an additional reinforcing lipogenic mechanism to SREBP-1c induction. J Clin Endocrinol Metab. 96:1424–1430. 2011. View Article : Google Scholar
33	Mak PA, Laffitte BA, Desrumaux C, et al: Regulated expression of the apolipoprotein E/C-I/C-IV/C-II gene cluster in murine and human macrophages. A critical role for nuclear liver X receptors alpha and beta. J Biol Chem. 277:31900–31908. 2002. View Article : Google Scholar : PubMed/NCBI
34	Berbée JF, van der Hoogt CC, Sundararaman D, Havekes LM and Rensen PC: Severe hypertriglyceridemia in human APOC1 transgenic mice is caused by apoC-I-induced inhibition of LPL. J Lipid Res. 46:297–306. 2005.PubMed/NCBI