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Qualitative and quantitative comparison of the cytotoxic and apoptotic potential of phytosterol oxidation products with their corresponding cholesterol oxidation products

Published online by Cambridge University Press:  08 March 2007

Eileen Ryan ,
Jay Chopra ,
Florence McCarthy ,
Anita R. Maguire  and
Nora M. O'Brien
Eileen Ryan
Affiliation:
Department of Food and Nutritional Sciences, University College, Cork, Ireland
Jay Chopra
Affiliation:
Department of Chemistry, Analytical and Biological Chemistry Research Facility, University College, Cork, Ireland
Florence McCarthy
Affiliation:
Department of Chemistry, Analytical and Biological Chemistry Research Facility, University College, Cork, Ireland
Anita R. Maguire
Affiliation:
Department of Chemistry, Analytical and Biological Chemistry Research Facility, University College, Cork, Ireland
Nora M. O'Brien*
Affiliation:
Department of Food and Nutritional Sciences, University College, Cork, Ireland
*
*Corresponding author: Dr Nora M. O'Brien, fax +353 21 4270244, email [email protected]
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Abstract

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Phytosterols contain an unsaturated ring structure and therefore are susceptible to oxidation under certain conditions. Whilst the cytotoxicity of the analogous cholesterol oxidation products (COP) has been well documented, the biological effects of phytosterol oxidation products (POP)have not yet been fully ascertained. The objective of the present study was to examine the cytotoxicity of β-sitosterol oxides and their corresponding COP in a human monocytic cell line (U937), a colonic adenocarcinoma cell line (CaCo-2) and a hepatoma liver cell line (HepG2). 7β-Hydroxysitosterol, 7-ketositosterol, sitosterol-3β,5α,6β-triol and a sitosterol-5α,6α-epoxide–sitosterol-5β,6β-epoxide (6:1) mixture were found to be cytotoxic to all three cell lines employed; the mode of cell death was by apoptosis in the U937 cell line and necrosis in the CaCo-2 and HepG2 cells. 7β-Hydroxysitosterol was the only β-sitosterol oxide to cause depletion in glutathione, indicating that POP-induced apoptosis may not be dependent on the generation of an oxidative stress. A further objective of this study was to assess the ability of the antioxidants α-tocopherol, γ-tocopherol and β-carotene to modulate POP-induced cytotoxicity in U937 cells. Whilst α/γ-tocopherol protected against 7β-hydroxycholesterol-induced apoptosis, they did not confer protection against 7β-hydroxysitosterol-or 7-ketositosterol-induced toxicity, indicating that perhaps COP provoke different apoptotic pathways than POP. β-Carotene did not protect against COP- or POP-induced toxicity. In general, results indicate that POP have qualitatively similar toxic effects to COP. However, higher concentrations of POP are required to elicit comparable levels of toxicity.

Keywords

Phytosterol oxidesCholesterol oxidesCytotoxicityApoptosis
Type
Research Article
Information
British Journal of Nutrition , Volume 94 , Issue 3 , September 2005 , pp. 443 - 451
Copyright
Copyright © The Nutrition Society 2005

References

Adcox, C, Boyd, L, Oehrl, L, Allen, J & Fenner, G (2001) Comparative effects of phytosterol oxides and cholesterol oxides in cultured macrophage-derived cell lines. J Agric Food Chem 49, 2090–2095.CrossRefGoogle ScholarPubMed
Aringer, L, Eneroth, P & Nordstrom, L (1976) Side chain hydroxylation of cholesterol, campesterol, and β-sitosterol in rat liver. J Lipid Res 17, 263–272.CrossRefGoogle ScholarPubMed
Berger, A, Jones, PJH & Abumweis, SS (2004) Plant sterols: factors affecting their efficacy and safety as functional food ingredients. http://www.lipidworld.com/content/3/1/5.Google Scholar
Borenfreund, E & Puerner, JA (1984) A simple quantitative procedure using monolayer cultures for cytotoxicity assay (HTD/NR-90). J Tissue Cult Methods 9, 7–9.CrossRefGoogle Scholar
Brown, AJ & Jessup, W (1999) Oxysterols and atherosclerosis. Atherosclerosis 142, 1–28.CrossRefGoogle ScholarPubMed
Buttriss, JL & Diplock, AT (1988) The α-tocopherol and phospholipids fatty acid content of rat liver subcellular membranes in vitamin E and selenium deficiency. Biochim Biophys Acta 963, 61–69.CrossRefGoogle ScholarPubMed
De Jong, N, Pijpers, L, Bleeker, JK & Ocke, MC (2004) Potential intake of phytosterols/stanols: results of a simulation study. Eur J Clin Nutr 58, 907–919.CrossRefGoogle ScholarPubMed
De Jong, N, Plat, J & Mensink, RP (2003) Metabolic effects of plant sterols and stanols. J Nutr Biochem 14, 362–369.CrossRefGoogle ScholarPubMed
Dubrez, L, Savoy, I, Hamman, A & Solary, E (1996) Pivotal role of a DEVD-sensitive step in etopside-induced and FAS mediated apoptotic pathways. EMBO J 15, 5504–5512.CrossRefGoogle Scholar
Dutta, PC (1997) Studies on phytosterol oxides: 2. Content in some vegetable oils and in french fries prepared in these oils. J Am Oil Chem Soc 74, 659–666.CrossRefGoogle Scholar
Dutta, PC & Appelqvist, LA (1997) Studies on phytosterol oxides: 1. Effect of storage on the content in potato chips prepared in different vegetable oils. J Am Oil Chem Soc 74, 647–657.CrossRefGoogle Scholar
Emanuel, HA, Hassel, CA, Addis, PB, Bergmann, SD & Zavoral, JH (1991) Plasma cholesterol oxidation products (oxysterols) in human subjects fed a meal rich in oxysterols. J Food Sci 56, 843–847.CrossRefGoogle Scholar
Grandgirard, A (2002) Biological effects of phytosterol oxidation products, future research and concluding remarks. In Cholesterol and Phytosterol Oxidation Products, Analysis, Occurrence, and Biological Effects, pp. 375–382 [Guardiola, F, Dutta, PC, Codony, R and Savage, GP, editors]. Champaign, IL: AOCS Press.Google Scholar
Grandgirard, A, Martine, L, Demaison, L, Cordelet, C, Joffre, C, Berdeaux, O & Semon, E (2004) Oxyphytosterols are present in plasma of healthy human subjects. Br J Nutr 91, 101–106.CrossRefGoogle ScholarPubMed
Grandgirard, A, Sergiel, JP, Nour, M, Demaison-Meloche, J & Ginies, C (1999) Lymphatic absorption of phytosterol oxides in rats. Lipids 34, 563–570.CrossRefGoogle ScholarPubMed
Higley, NA & Taylor, SL (1984) The steatotic and cytotoxic effects of cholesterol oxides in cultured L cells. Food Chem Toxicol 22, 983–992.CrossRefGoogle ScholarPubMed
Hissin, PJ & Hilf, R (1976) A fluorometric method for determination of oxidised and reduced glutathione in tissues. Anal Biochem 74, 214–226.CrossRefGoogle ScholarPubMed
Jacobson, MS, Price, MG, Shamoo, AE & Heald, FP (1985) Atherogenesis in white carneau pigeons: effects of low-level cholestane-triol feeding. Atherosclerosis 57, 209–217.CrossRefGoogle ScholarPubMed
Kakis, G, Kuksis, A & Myher, JJ (1977) Injected 7-oxycholesterol and plant sterol derivatives and hepatic cholesterogenesis. Adv Exp Med Biol 82, 297–299.Google Scholar
Lee, K, Herian, AM & Higley, NA (1985) Sterol oxidation products in french fries and in stored potato chips. J Food Protect 48, 158–161.CrossRefGoogle ScholarPubMed
Leonarduzzi, G, Sottero, B & Poli, G (2002) Oxidised products of cholesterol: dietary and metabolic origin, and proatherosclerotic effects. J Nutr Biochem 13, 700–710.CrossRefGoogle ScholarPubMed
Li, S & Wilson, WK (1999) Sterol synthesis. Preparation and characterization of fluorinated and deuterated analogs of oxygenated derivatives of cholesterol. Chem Phys Lipids 99, 33–71.CrossRefGoogle ScholarPubMed
Lizard, G, Gueldry, S, Sordet, O, Monier, S, Athias, A, Miguet, C, Bessede, G, Lemaire, S, Solary, E & Gambert, P (1998) Glutathione is implied in the control of 7-ketocholesterol-induced apoptosis, which is associated with radical oxygen species production. FASEB J 12, 1651–1663.CrossRefGoogle ScholarPubMed
Lizard, G, Miguet, C, Bessede, G, Monier, S, Gueldry, S, Neel, D & Gambert, P (2000) Impairment with various antioxidants of the loss of mitochondrial transmembrane potential of cytosolic release of cytochrome c occulting during 7-ketocholesterol-induced apoptosis. Free Radic Biol Med 28, 743–753.CrossRefGoogle Scholar
Lizard, G, Monier, S, Cordelet, C, Gesquiere, L, Deckert, V, Gueldry, S, Lagrost, L & Gambert, P (1999) Characterisation and comparison of the mode of cell death, apoptosis versus necrosis, induced by 7β-hydroxycholesterol and 7-ketocholesterol in the cells of the vascular wall. Arterioscler Thromb Vasc Biol 19, 1190–1200.CrossRefGoogle ScholarPubMed
Lyons, N, Woods, JA & O'Brien, NM (2001) α-Tocopherol but not γ-tocopherol inhibits 7β-hydroxycholesterol-induced apoptosis in human U937 cells. Free Radic Res 35, 329–339.CrossRefGoogle ScholarPubMed
McCarty, FO, Chopra, J, Ford, A, Hogan, SA, Kerry, JP, O'Brien, NM et al. (2005) Synthesis, isolation and characterisation of Baitosterol and β-sitosterol derivations. Org Biomol Chem 3, 3059.CrossRefGoogle Scholar
Maguire, L, Konoplyannikov, M, Ford, A, Maguire, AR & O'Brien, NM (2003) Comparison of the cytotoxic effects of β-sitosterol oxides and a cholesterol oxide, 7β-hydroxycholesterol, in cultured mammalian cells. Br J Nutr 90, 767–775.CrossRefGoogle Scholar
Matthias, D, Becker, CH, Godicke, W, Schmidt, R & Ponsold, K (1987) Action of cholestane-3βa,5α,6β-triol on rats with particular reference to aorta. Atherosclerosis 63, 115–124.CrossRefGoogle Scholar
Meyer, W, Jungnickel, H, Janijke, M, Dettner, K & Spitellier, G (1998) On the cytotoxicity of oxidised phytosterols isolated from photoautotrophic cell cultures of Chenopodium rubrum tested on meal-worms Tenebrio molitor. Phytochemistry 47, 789–797.CrossRefGoogle Scholar
Meyer, W & Spitellier, G (1997) Oxidised phytosterols increase by ageing in photoautotrophic cell cultures of Chenopodium rubrum. Phytochemistry 45, 297–302.CrossRefGoogle Scholar
Miguet-Alfonsi, C, Prunet, C, Monier, S, Bessede, G, Lemaire-Ewing, S, Berthier, A, Menetrier, F, Neel, D, Gambert, P & Lizard, G (2002) Analysis of oxidative processes and of myelin figures formation before and after the loss of mitochondrial transmembrane potential during 7β-hydroxycholesterol and 7-ketocholesterol-induced apoptosis: comparison with various pro-apoptotic chemicals. Biochem Pharmacol 64, 527–541.CrossRefGoogle ScholarPubMed
Moreau, RA, Whitaker, BD & Hicks, KB (2002) Phytosterols, phytostanols, and their conjugates in foods: structural diversity, quantitative analysis, and health promoting uses. Prog Lipid Res 41, 457–500.CrossRefGoogle ScholarPubMed
Mowels, JM (1990) Mycoplasma detection Animal Cell Culture vol. V pp. 65–74 [Pollard, JW and Walker, JM, editors]. Clifton, NJ: Humana Press.CrossRefGoogle Scholar
Nourooz-Zadeh, J & Appelqvist, LA (1992) Isolation and quantitative determination of sterol oxides in plant-based foods: soybean oil and wheat flour. J Am Oil Chem Soc 69, 288–293.CrossRefGoogle Scholar
O'Callaghan, YC, Woods, JA, O'Brien, NM (1999) Oxysterol-induced cell death in U937 and HepG2 cells at reduced and normal serum concentrations. Eur J Nutr 38, 255–262.CrossRefGoogle ScholarPubMed
O'Callaghan, YC, Woods, JA & O'Brien, NM (1999) Oxysterol-induced cell death in U937 and HepG2 cells at reduced and normal serum concentrations. Eur J Nutr 38, 255–262.CrossRefGoogle ScholarPubMed
O'Callaghan, YC, Woods, JA & O'Brien, NM (2001) Comparative study of the cytotoxicity and apoptosis-inducing potential of commonly occurring oxysterols. Cell Biol Toxicol 7, 127–137.CrossRefGoogle Scholar
O'Callaghan, YC, Woods, JA & O'Brien, NM (2002) Characteristics of 7β-hydroxycholesterol-induced cell death in a human monocytic blood cell line, U937, and a human hepatoma cell line, HepG2. Toxicol In Vitro 16, 245–251.CrossRefGoogle Scholar
Ostlund, RE Jr (2002) Phytosterols in human nutrition. Annu Rev Nutr 22, 533–549.CrossRefGoogle ScholarPubMed
Pakrashi, A & Basak, B (1976) Abortifacient effect of steroids from Ananas comosus and their analogues on mice. J Reprod Fertil 46, 461–462.CrossRefGoogle ScholarPubMed
Peng, SK, Tham, P, Taylor, CB & Mikkelson, B (1979) Cytotoxicity of oxidation derivatives of cholesterol on cultured aortic smooth muscle cells and their effect on cholesterol biosynthesis. Am J Clin Nutr 32, 1033–1042.CrossRefGoogle ScholarPubMed
Peterson, AR, Peterson, H, Spears, CP, Trosko, JE & Sevanian, A (1988) Mutagenic characterisation of cholesterol epoxides in Chinese hamster V79 cells. Mutat Res 203, 355–366.CrossRefGoogle ScholarPubMed
Plat, J, Brzezinka, H, Lutjohann, D, Mensink, RP, Von Bergmann, K (2001) Oxidised plant sterols in human serum and lipid infusions as measured by combined gas–liquid chromatography-mass spectrometry. J Lipid Res 42, 2030–2038.CrossRefGoogle ScholarPubMed
Rosenblat, M & Aviram, M (2002) Oxysterol-induced activation of macrophage NADPH-oxidase enhances cell-mediated oxidation of LDL in the atherosclerotic apolipoprotein E deficient mouse: inhibitory role of vitamin E. Atherosclerosis 160, 69–80.CrossRefGoogle Scholar
Ryan, L, O'Callaghan, YC & O'Brien, NM (2004 a) Comparison of the apoptotic processes induced by the oxysterols 7β-hydroxycholesterol and cholesterol-5β,6β-epoxide. Cell Biol Toxicol 20, 313–323.CrossRefGoogle ScholarPubMed
Ryan, L, O'Callaghan, YC & O'Brien, NM (2004 b) Generation of an oxidative stress precedes caspase activation during 7β-hydroxycholesterol-induced apoptosis in U937 cells. J Biochem Mol Toxicol 18, 50–59.CrossRefGoogle ScholarPubMed
Sevanian, A & Peterson, AR (1986) The cytotoxic and mutagenic properties of cholesterol oxidation products. Food Chem Toxicol 24, 1103–1110.CrossRefGoogle ScholarPubMed
Smith, PK, Krohn, RI, Hermanson, GT, Mallia, AK, Gartner, FH, Provenzano, MD, Fujimoto, EK, Goeke, NM, Olson, BJ & Klenk, DC (1985) Measurement of protein using bicinchoninic acid. Anal Biochem 150, 76–85.CrossRefGoogle ScholarPubMed
Strauss, GHS (1991) Non-random cell killing in cryopreservation: implications for performance of the battery of leukocyte tests (BLT), 1. Toxic and immunotoxic effects. Mutat Res 252, 1–15.CrossRefGoogle ScholarPubMed
Tai, CY, Chen, YC & Chen, BH (1999) Analysis, formation and inhibition of cholesterol oxidation products in foods: an overview (Part 1). J Food Drug Anal 7, 243–257.Google Scholar
Tapiero, H, Townsend, DM & Tew, KD (2004) The role of carotenoids in the prevention of human pathologies. Biomed Pharmacother 58, 100–110.CrossRefGoogle ScholarPubMed
Therond, P, Abella, A, Laurent, D, Couturier, M, Chalas, J, Legrand, A & Lindenbaum, A (2000) In vitro study of the cytotoxicity of isolated oxidised low-density lipoprotein fractions in human endothelial cells: relationship with the glutathione status and cell morphology. Free Radic Biol Med 28, 585–596.CrossRefGoogle ScholarPubMed
Tomoyori, H, Kawata, Y, Higuchi, T, Ichi, I, Sato, H, Sato, M, Ikeda, I & Imaizumi, K (2004) Phytosterol oxidation products are absorbed in the intestinal lymphatics in rats but do not accelerate atherosclerosis in apolipoprotein-E deficient mice. J Nutr 134, 1690–1696.CrossRefGoogle Scholar
Tran, K & Chan, AC (1992) Comparative uptake of α-tocopherol and γ-tocopherol by human endothelial cells. Lipids 27, 38–41.CrossRefGoogle ScholarPubMed
Turchetto, E, Lercker, G & Bortolomeazzi, R (1993) Oxisterol determination in selected coffees. Toxicol Ind Health 9, 519–527.CrossRefGoogle ScholarPubMed
Uemura, M, Hiroki, M, Yoshida, N, Fujita, N, Ochiai, J, Matsumoto, N, Takagi, T & Yoshikawa, T (2002) α-Tocopherol prevents apoptosis of vascular endothelial cells via a mechanism exceeding that of mere antioxidation. Eur J Pharmacol 456, 29–37.CrossRefGoogle Scholar