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Flaxseed reduces plasma cholesterol and atherosclerotic lesion formation in ovariectomized Golden Syrian hamsters

      Abstract

      Background: Dietary modification contributes significantly in reducing cardiovascular disease (CVD) risk factors including lowering cholesterol and atherosclerosis. The purpose of this study was to investigate the effects of flaxseed, a rich source of lignans, α-linolenic acid and soluble fiber mucilage, on the prevention of ovariectomy-induced rise in total cholesterol and atherosclerotic lesions. Methods: Seventy-two 6-month-old female Golden Syrian hamsters were either ovariectomized (ovx) or sham-operated (sham) and randomly assigned to six groups (n=12): sham, ovx, or ovx plus either 17β-estradiol (E2, 10 μg/kg body weight) or semi-purified diet adjusted for macronutrients and fiber to contain one of the three doses of flaxseed (7.5, 15, or 22.5%) for 120 days. Results: Ovariectomy significantly elevated plasma total-, HDL-, and free-cholesterol concentrations. Similar to estrogen, all doses of flaxseed were effective in preventing the ovx-induced rise in plasma total cholesterol. Triglyceride concentrations were significantly higher in the flax-fed hamsters. There were no significant differences in plasma non-HDL- and esterified-cholesterol among the treatment groups. Ovariectomy also increased the number of hamsters with lesions and the aortic fatty streak area. All three doses of flaxseed reduced the fatty streak area and the incidence of lesions to levels similar to the sham group. Conclusion: The findings of this study show that flaxseed is beneficial in reducing plasma cholesterol and plaque formation induced by ovarian hormone deficiency.

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      References

      1. Heart and stroke facts: statistical update, 2003.

        • Clarkson T.B
        The new conundrum: do estrogens have any cardiovascular benefits?.
        Int J Fertil Womens Med. 2002; 47: 61-68
        • Judd H.L
        • Meldrum D.R
        • Deftos L.J
        • et al.
        Estrogen replacement therapy: indications and complications.
        Ann Int Med. 1983; 98: 195-205
        • Lissin L.W
        • Cooke J.P
        Phytoestrogens and cardiovascular health.
        J Am Coll Cardiol. 2000; 35: 1403-1410
      2. Cunnane SC, Thompson LU, editors. Flaxseed in human nutrition. Champaign, IL: AOCS Press, 1995.

        • Babu U.S
        • Mitchell G.V
        • Wiesenfeld P
        • et al.
        Nutritional and hematological impact of dietary flaxseed and defatted flaxseed meal in rats.
        Int J Food Sci Nutr. 2000; 51: 109-117
        • Ratnayake W.M.N
        • Behrens W.A
        • Fischer P.W.F
        • et al.
        Chemical and nutritional studies of flaxseed variety Linott in rats.
        J Nutr Biochem. 1992; 3: 232-240
        • Cunnane S.C
        • Hamadeh M.J
        • Liede A.C
        • et al.
        Nutritional attributes of traditional flaxseed in healthy young adults.
        Am J Clin Nutr. 1995; 61: 62-68
        • Bierenbaum M.L
        • Reichstein R
        • Watkins T.R
        Reducing atherogenic risk in hyperlipemic humans with flax seed supplementation: a preliminary report.
        J Am Coll Nutr. 1993; 12: 501-504
        • Jenkins D.J
        • Kendall C.W
        • Vidgen E
        • et al.
        Health aspects of partially defatted flaxseed, including effects on serum lipids, oxidative measures, and ex vivo androgen and progestin activity: a controlled crossover trial.
        Am J Clin Nutr. 1999; 69: 395-402
        • Lucas E.A
        • Wild R.D
        • Hammond L.J
        • et al.
        Flaxseed improves lipid profile without altering biomarkers of bone metabolism in postmenopausal women.
        Clin Endocrinol Metab. 2002; 87: 1527-1532
        • Prasad K
        Dietary flax seed in prevention of hypercholesterolemic atherosclerosis.
        Atherosclerosis. 1997; 132: 69-76
        • Prasad K
        Reduction of serum cholesterol and hypercholesterolemic atherosclerosis in rabbits by secoisolariciresinol diglucoside isolated from flaxseed.
        Circulation. 1999; 99: 1355-1362
        • Prasad K
        • Mantha S.V
        • Muir A.D
        • et al.
        Reduction of hypercholesterolemic atherosclerosis by CDC-flaxseed with very low alpha-linolenic acid.
        Atherosclerosis. 1998; 136: 367-375
        • Lucas E
        • Khalil D.A
        • Daggy B.P
        • et al.
        Ethanol-extracted soy protein isolate does not modulate serum cholesterol in Golden Syrian hamsters: a model of postmenopausal hypercholesterolemia.
        J Nutr. 2001; 131: 211-214
        • Lucas E.A
        • Lightfoot S.A
        • Hammond L.J
        • et al.
        Soy isoflavones prevent ovariectomy-induced hypercholesterolemia and atherosclerotic lesions in Golden Syrian hamsters.
        J North Am. Menopause Soc. 2003; 10: 314-321
        • Terpstra A.H.M
        • Holmes J.C
        • Nicolosi R.J
        The hypercholesterolemic effect of dietary soybean protein vs casein in hamsters fed cholesterol enriched or cholesterol-free semipurified diets.
        J Nutr. 1991; 121: 944-947
        • Searcy R.L
        • Bergquist L.M
        A new color reaction for the quantitation of serum cholesterol.
        Clin Chim Acta. 1960; 5: 192-199
        • Folch J
        • Lees M
        • Sloane-Stanley G.H
        A simple method for isolation and purification of total lipids from animal tissue.
        J Biol Chem. 1957; 226: 497-509
        • Harris W.S
        n-3 fatty acids and serum lipoproteins: animal studies.
        Am J Clin Nutr. 1997; 65: 1611S-1616S
        • Sohn E
        • Daggy B.P
        • Arjmandi B.H
        Ovariectomized hamster: a potential model of postmenopausal hypercholesterolemia.
        J Nutr Biochem. 1999; 10: 660-663
        • Renaud S.C
        • Lanzmann-Petithory D
        Alpha-linolenic acid in the prevention of cardiovascular diseases.
        World Rev Nutr Diet. 2001; 88: 79-85
        • Kuroda T
        • Kondo K
        • Iwasaki T
        • et al.
        Synthesis and hypolipidemic activity of diesters of arylnaphthalene lignan and their heteroaromatic analogs.
        Chem Pharm Bull (Tokyo). 1997; 45: 678-684
      3. Sanghvi A, Diwen WF, Seltman H, Inhibition of rat liver cholesterol 7-alpha hydroxylase acyl CoA:cholesterol acyltransferase activities by enterodiol and enterolactone. In: Krietchevsky D, editors, Proceedings of the Symposium on Drugs Affecting Lipid Metabolism. New York: Plenum Press, 1984. p. 311–22.

        • Bhathena S.J
        • Ali A.A
        • Mohamed A.I
        • et al.
        Differential effects of dietary flaxseed protein and soy protein on plasma triglyceride and uric acid levels in animal models.
        J Nutr Biochem. 2002; 13: 684-689
        • Bhathena S.J
        • Ali A.A
        • Haudenschild C
        • et al.
        Dietary flaxseed meal is more protective than soy protein concentrate against hypertriglyceridemia and steatosis of the liver in an animal model of obesity.
        J Am Coll Nutr. 2003; 2: 157-164
        • Tabas I
        Cholesterol in health and disease.
        J Clin Invest. 2002; 110: 583-590