Objective: The incidence of cardiovascular disease dramatically increases during menopause, and postmenopausal women seek natural alternatives to hormone therapy. Flaxseed can slow the progression of atherosclerotic lesion formation; however, it is not known whether it can reverse formation that has already occurred.
Methods: Seventy-two female Golden Syrian hamsters were randomly divided into six groups (n = 12), sham-operated (sham) or ovariectomized (ovx), and kept on the same diet for 120 days to allow for atherosclerotic lesion development. After this 120-day period, whole flaxseed was introduced to the diets of hamsters in three of the groups: group 1 (sham + casein); group 2 (ovx + casein); group 3 (ovx + 7.5% flaxseed); group 4 (ovx + 15% flaxseed); group 5 (ovx + 22.5% flaxseed); and group 6 (ovx + 17β-estradiol). This diet was maintained for an additional 120 days. Lesion regression was examined histologically, and serum was analyzed for total cholesterol, triglyceride, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, Apo A, Apo B, and lipoprotein(a).
Results: Results showed that 15% and 22.5% flaxseed, compared with ovx animals, significantly reduced lipoprotein(a) (4.4 mg/dL [ovx] vs 2.15 mg/dL [15% flaxseed] and 0.3 mg/dL [22.5% flaxseed]; P < 0.05) and Apo B (2.8 mg/dL [ovx] vs 2.4 mg/dL [15% flaxseed] and 2.5 mg/dL [22.5% flaxseed]). Flax reduced by 67% the number of animals with aortic arch lesions.
Conclusions: All three doses of flax reduce the severity of lesion formation compared with ovx controls. These results support the efficacy of flaxseed in reducing cardiovascular disease risk.
From the 1Department of Exercise Science and Sports Studies, Rutgers, The State University of New Jersey, New Brunswick, NJ; 2Department of Nutrition, Food, and Exercise Science, Florida State University, Tallahassee, FL; and 3Department of Pathology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK.
Received November 21, 2012; revised and accepted February 12, 2013.
S.C.C. and B.H.A. designed the research. S.C.C. conducted the research. R.L.S. analyzed data using a clinical analyzer. N.B. and B.H.A. performed ovariectomy. M.R.L. and S.A.L. conducted histological analysis and read slides. S.C.C. conducted statistical analysis, wrote the article, and had primary responsibility for the final content. All authors read and approved the final manuscript.
Funding/support: This work was supported by US Department of Agriculture National Research Initiative grant 2008-01926 (to S.C.C.).
Financial disclosure/conflicts of interest: None reported.
Address correspondence to: Sara C. Campbell, PhD, Department of Exercise Science and Sports Studies, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901. E-mail: firstname.lastname@example.org