Background/Aims: To analyze the effects of pomegranate juice (PJ) and punicalagin on macrophage triglyceride metabolism. Methods: Triglyceride metabolism was analyzed in PJ- or punicalagin-treated J774A.1 macrophages or in mouse peritoneal macrophages (MPM) harvested from C57BL/6 mice or from paraoxonase 2 (PON2)-deficient mice. Results: PJ (0–50 µM) significantly and dose-dependently decreased the triglyceride content and triglyceride biosynthesis rate in J774A.1 macrophages or in C57BL/6 MPM by about 30%. Similarly, punicalagin, the major PJ polyphenol, inhibited the MPM triglyceride biosynthesis rate by 40%. The triglyceride hydrolytic rate, however, was not significantly affected by PJ or punicalagin. The activity of diacylglycerol acyltransferase 1 (DGAT1; the rate-limiting enzyme in triglyceride biosynthesis) was significantly inhibited, by 54%, in C57BL/6 MPM that were treated with 50 µM PJ or punicalagin, with no significant effect on DGAT1 mRNA or protein expression. Both PJ and punicalagin increased (1.7-fold) MPM PON2 mRNA expression, and PON2 was previously shown to inhibit DGAT1 activity. However, the addition of PJ or punicalagin (50 µM) to microsomes from PON2-deficient MPM still resulted in a significant reduction (50–58%) in DGAT1 activity. Conclusions: We conclude that the inhibitory effect of PJ on triglyceride biosynthesis could be attributed to a direct effect of PJ on DGAT1 activity.

Carmena R, Duriez P, Fruchart JC: Atherogenic lipoprotein particles in atherosclerosis. Circulation 2004;109:III2–III7.
Cullen P: Evidence that triglycerides are an independent coronary heart disease risk factor. Am J Cardiol 2000;86:943–949.
Aviram M, Rosenblat M: Paraoxonases 1, 2 and 3, oxidative stress, and macrophage foam cell formation during atherosclerosis development. Free Radic Biol Chem 2004;37:1304–1316.
Tiwari RL, Singh Y, Barthwal MK: Macrophages: an elusive yet emerging therapeutic target of atherosclerosis. Med Res Rev 2008;28:483–544.
Lusis AJ: Atherosclerosis. Nature 2000:404:233–241.
Lundberg B: Chemical composition and physical state of lipid deposits in atherosclerosis. Atherosclerosis 1985;56:93–110.
Lang PD, Insull W Jr: Lipid droplets in atherosclerotic fatty streaks of human aorta. J Clin Invest 1970;49:1479–1488.
Mattsson L, Johansson H, Ottosson M, Bondjers G, Wilklund O: Expression of lipoprotein lipase mRNA and secretion in macrophages isolated from human atherosclerotic aorta. J Clin Invest 1993;92:1759–1765.
Aronis A, Madar Z, 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 2005;38:1221–1230.
Gil MI, Tomás-Barberán FA, Hess-Pierce B, Holcroft DM, Kader AA: Antioxidant activity of pomegranate juice and its relationship with phenolic composition and processing. J Agric Food Chem 2000;48:4581–4589.
Tzulker R, Glazer I, Bar-Ilan I, Holland D, Aviram M, Amir R: Antioxidant activity, polyphenol content, and related compounds in different fruit juices and homogenates prepared from 29 different pomegranate accessions. J Agric Food Chem 2007;55:9559–9570.
Basu A, Penugonda K: Pomegranate juice: a heart-healthy fruit juice. Nutr Rev 2009;67:49–56.
Aviram M, Dornfeld L, Rosenblat M, Volkova N, Kaplan M, Coleman R, Hayek T, Presser D, Fuhrman B: Pomegranate juice consumption reduces oxidative stress, atherogenic modifications to LDL, and platelet aggregation: studies in humans and in atherosclerotic apolipoprotein E-deficient mice. Am J Clin Nutr 2000;71:1062–1076.
Aviram M, Rosenblat M, Gaitini D, Nitecki S, Hoffman A, Dornfeld L, Volkova N, Presser D, Attias J, Liker H, Hayek T: Pomegranate juice consumption for 3 years by patients with carotid artery stenosis reduces common carotid intima-media thickness, blood pressure and LDL oxidation. Clin Nutr 2004;23:423–433.
Davidson MH, Maki KC, Dicklin MR, Feinstein SB, Witchger M, Bell M, McGuire DK, Provost JC, Liker H, Aviram M: Effects of consumption of pomegranate juice on carotid intima-media thickness in men and women at moderate risk for coronary heart disease. Am J Cardiol 2009;104:936–942.
Rosenblat M, Hayek T, Aviram M: Anti-oxidative effects of pomegranate juice (PJ) consumption by diabetic patients on serum and on macrophages. Atherosclerosis 2006;187:363–371.
Rock W, Rosenblat M, Miller-Lotan R, Levy AP, Elias M, Aviram M: Consumption of wonderful variety pomegranate juice and extract by diabetic patients increases paraoxonase 1 association with high-density lipoprotein and stimulates its catalytic activities. J Agric Food Chem 2008;56:8704–8713.
Fuhrman B, Volkova N, Aviram M: Pomegranate juice polyphenols increase recombinant paraoxonase-1 binding to high-density lipoprotein: studies in vitro and in diabetic patients. Nutrition 2010;26:359–366.
Kaplan M, Hayek T, Raz A, Coleman R, Dornfeld L, Vaya J, Aviram M: Pomegranate juice supplementation to atherosclerotic mice reduces macrophage lipid peroxidation, cellular cholesterol accumulation and development of atherosclerosis. J Nutr 2001;131:2082–2089.
Aviram M, Volkova N, Coleman R, Dreher M, Reddy MK, Ferreira D, Rosenblat M: Pomegranate phenolics from the peels, arils, and flowers are antiatherogenic: studies in vivo in atherosclerotic apolipoprotein E-deficient (E0) mice and in vitro in cultured macrophages and lipoproteins. J Agric Food Chem 2008;56:1148–1157.
Fuhrman B, Volkova N, Aviram M: Pomegranate juice inhibits oxidized LDL uptake and cholesterol biosynthesis in macrophages. J Nutr Biochem 2005;16:570–576.
Draganov DI, Teiber JF, Speelman A, Osawa Y, Sunahara R, La Du BN: Human paraoxonases (PON1, PON2, and PON3) are lactonases with overlapping and distinct substrate specificities. J Lipid Res 2005;46:1239–1247.
Ng CJ, Wadleigh DJ, Gangopadhyay A, Hama S, Grijalva VR, Navab M, Fogelman AM, Reddy ST: Paraoxonase-2 is a ubiquitously expressed protein with antioxidant properties and is capable of preventing cell-mediated oxidative modification of low density lipoprotein. J Biol Chem 2001;76:44444–44449.
Rosenblat M, Draganov D, Watson CE, Bisgaier CL, La Du BN, Aviram M: Mouse macrophage paraoxonase 2 activity is increased whereas cellular paraoxonase 3 activity is decreased under oxidative stress. Arterioscler Thromb Vasc Biol 2003;23:468–474.
Ng CJ, Bourquard N, Grijalva V, Hama S, Shih DM, Navab M, Fogelman AM, Lusis AJ, Young S, Reddy ST: Paraoxonase-2 deficiency aggravates atherosclerosis in mice despite lower apolipoprotein-B-containing lipoproteins: anti-atherogenic role for paraoxonase-2. J Biol Chem 2006;281:29491–29500.
Rosenblat M, Coleman R, Reddy ST, Aviram M: Paraoxonase 2 attenuates macrophage triglyceride accumulation via inhibition of diacylglycerol acyltransferase 1. J Lipid Res 2009;50:870–879.
Meilin E, Aviram M, Hayek T: Paraoxonase 2 (PON2) decreases high glucose-induced macrophage triglycerides (TG) accumulation, via inhibition of NADPH-oxidase and DGAT1 activity: studies in PON2-deficient mice. Atherosclerosis 2010;208:390–395.
Shiner M, Fuhrman B, Aviram M: Macrophage paraoxonase 2 (PON2) expression is up-regulated by pomegranate juice phenolic anti-oxidants via PPAR gamma and AP-1 pathway activation. Atherosclerosis 2007;195:313–321.
Rosenblat M, Volkova N, Aviram M: Pomegranate juice (PJ) consumption antioxidative properties on mouse macrophages, but not PJ beneficial effects on macrophage cholesterol and triglyceride metabolism, are mediated via PJ-induced stimulation of macrophage PON2. Atherosclerosis 2010;212:86–92.
Lowry OH, Rosebrough NJ, Farr AL, Randall RJ: Protein measurement with the Folin phenol reagent. J Biol Chem 1951;193:265–275.
Napolitano M, Avella M, Botham KM, Bravo E: Chylomicrons remnant induction of lipid accumulation in J774A.1 macrophages is associated with up-regulation of triacylglycerol synthesis which is not dependent on oxidation of the particles. Biochim Biophys Acta 2003;1631:255–264.
Vaziri ND, Kim CH, Phan D, Kim S, Liang K: Up-regulation of hepatic acylCoA: diacylglycerol acyltransferase-1 (DGAT1) expression in nephrotic syndrome. Kidney Int 2004;66:262–267.
Chandak PG, Radovic B, Aflaki E, Kolb D, Buchebner M, Fröhlich E, Magnes C, Sinner F, Haemmerle G, Zechner R, Tabas I, Levak-Frank S, Kratky D: Efficient phagocytosis requires triacylglycerol hydrolysis by adipose triglyceride lipase. J Biol Chem 2010;285:20192–20201.
Farese RV Jr, Cases S, Smith SJ: Triglyceride synthesis: insights from the cloning of diacylglycerol acyltransferase. Curr Opin Lipidol 2000;11:229–234.
Cases S, Smith SJ, Zheng YW, Myers HM, Lear SR, Sande E, Nivak S, Collins C, Welch CB, Lusis AJ, Erickson SK, Farese RV Jr: Identification of a gene encoding an acyl CoA:diacylglycerol acyltransferase, a key enzyme in triacylglycerol synthesis. Proc Natl Acad Sci USA 1998;95:13018–13023.
Maor I, Kaplan M, Hayek T, Vaya J, Hoffman A, Aviram M: Oxidized monocyte-derived macrophages in aortic atherosclerotic lesion from apolipoprotein E-deficient mice and from human carotid artery contain lipid peroxides and oxysterols. Biochem Biophys Res Commun 2000;269:775–780.
Moore EH, Napolitano M, Prosperi A, Avella M, Suckling KE, Bravo E, Botham KM: Incorporation of lycopene into chylomicron remnant-like particles enhances their induction of lipid accumulation in macrophages. Biochem Biophys Res Commun2003;312:1216–1219.
Lehner R, Kusis A: Biosynthesis of triacylglycerol. Prog Lipid Res 1996;35:169–201.
Coleman RA, Lee DP: Enzymes of triacylglycerol synthesis and their regulation. Prog Lipid Res 2004;43:134–176.
Yu YH, Zhang Y, Olelkers P, Stephen L, Sturley ST, Rader DJ, Ginsberg HN: Posttranscriptional control of the expression and function of diacylglycerol acyltransferase-1 in mouse adipocytes. J Biol Chem 2002;277:50876–50884.
Casaschi A, Maiyoh GK, Adeli K, Theriault AG: Increased diacylglycerol acyltransferase activity is associated with triglyceride accumulation in tissues of diet-induced insulin-resistant hyperlipidemic hamsters. Metabolism 2005;54:403–409.
Casaschi A, Wang Q, Dang K, Richards A, Theriault A: Intestinal apolipoprotein B secretion is inhibited by the flavonoid quercetin: potential role of microsomal triglyceride transfer protein and diacylglycerol acyltransferase. Lipids 2002;37:647–652.
Casaschi A, Rubio BK, Maiyoh GK, Theriault AG: Inhibitory activity of diacylglycerol acyltransferase (DGAT) and microsomal triglyceride transfer protein (MTP) by the flavonoid, taxifolin, in HepG2 cells: potential role in the regulation of apolipoprotein B secretion. Atherosclerosis 2004;176:247–253.
Cerdá B, Llorach R, Cerón JJ, Espín JC, Tomás-Barberán FA: Evaluation of the bioavailability and metabolism in the rat of punicalagin, an antioxidant polyphenol from pomegranate juice. Eur J Nutr 2003;42:18–28.
Aronis A, Madar Z, Tirosh O: Lipotoxic effects of triacylglycerols in J774.2 macrophages. Nutrition 2008;24:167–176.
Seeram NP, Henning SM, Zhang Y, Suchard M, Li Z, Heber D: Pomegranate juice ellagitannin metabolites are present in human plasma and some persist in urine for up to 48 h. J Nutr 2006;136:2481–2485.
Kasimsetty SG, Bialonska D, Reddy MK, Ma G, Khan SI, Ferreira D: Colon cancer chemopreventive activities of pomegranate ellagitannins and urolithins. J Agric Food Chem 2010;58:2180–2187.
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.