Consumption of isoflavone-rich soy protein does not alter homocysteine or markers of inflammation in postmenopausal women.
OBJECTIVE
To investigate the effect of soy protein containing isoflavones on homocysteine (Hcy), C-reactive protein (CRP), soluble E-selectin (sE-selectin), soluble vascular adhesion molecule-1 (sVCAM-1) and soluble intercellular adhesion molecule-1 (sICAM-1).


METHODS
In a randomized crossover design, 34 postmenopausal women consumed soy protein isolate (26+/-5 g protein containing 44+/-8 mg isoflavones per day) or milk protein isolate (26+/-5 g protein per day) for 6 weeks each. Fasting blood samples were collected at the end of each diet period and end points analyzed by enzyme-linked immunosorbent assay.


RESULTS
Concentrations of Hcy, CRP, sE-selectin, sVCAM-1 and sICAM-1 were not different between soy and milk diet treatments. Results did not differ by equol production status or by baseline lipid concentration. Adjustment for intake of folate and methionine did not alter the Hcy results.


CONCLUSIONS
These data suggest that decreasing vascular inflammation and Hcy concentration are not likely mechanisms by which soy consumption reduces coronary heart disease risk.
Greany
K A
KA
Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN 55108, USA.
Nettleton
J A
JA
Wangen
K E
KE
Thomas
W
W
Kurzer
M S
MS
D000368:Aged; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000378:metabolism; D003327:Coronary Disease / Q000097:blood* / Q000453:epidemiology / Q000517:prevention & control; D018592:Cross-Over Studies; D019040:E-Selectin / Q000097:blood; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005215:Fasting; D005260:Female; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D007249:Inflammation / Q000097:blood* / Q000453:epidemiology / Q000517:prevention & control; D018799:Intercellular Adhesion Molecule-1 / Q000097:blood; D007529:Isoflavones / Q000008:administration & dosage*; D008875:Middle Aged; D008894:Milk Proteins / Q000008:administration & dosage; D017698:Postmenopause / Q000097:blood*; D030262:Soybean Proteins / Q000008:administration & dosage*; D019010:Vascular Cell Adhesion Molecule-1 / Q000097:blood