This Article Full Text Full Text (PDF) All Versions of this Article: 90/7/3956    most recent Author Manuscript (PDF) Submit a related Letter to the Editor Purchase Article View Shopping Cart Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Huang, Y. Articles by Lu, L.-J. W. Search for Related Content PubMed PubMed Citation Articles by Huang, Y. Articles by Lu, L.-J. W. Related Collections Female Endocrinology

Decreased Circulating Levels of Tumor Necrosis Factor- in Postmenopausal Women during Consumption of Soy-Containing Isoflavones

Departments of Preventive Medicine and Community Health (Y.H., S.C., K.E.A., J.J.G., L.-J.W.L.) and Obstetrics and Gynecology (M.N.), the University of Texas Medical Branch, Galveston, Texas 77555-1109

Address all correspondence and requests for reprints to: Lee-Jane W. Lu, Ph.D., the Department of Preventive Medicine and Community Health, The University of Texas Medical Branch, 700 Harborside Drive, Galveston, Texas 77555-1109. E-mail: llu{at}utmb.edu.

Context: TNF- is a key mediator of inflammatory responses and may play a pivotal role in the development of cancer and in bone resorption.

Objective: This study determined the effect of soy rich in isoflavones on levels of TNF-.

Design: Twelve postmenopausal women ingested a 36-oz portion of soymilk containing isoflavones daily for 16 wk and provided fasting blood samples multiple times before, during, and after soy consumption for the analyses of cytokines and monocyte content.

Results: Compared with prediet levels (36.3 ± 14.0 pg/ml), serum levels of TNF- decreased by 25.1% (27.2 ± 10.3 pg/ml; P < 0.01) as early as 2 wk after soy consumption and by 66.7% (11.6 ± 5.3 pg/ml; P < 0.01) 10 wk after soy consumption and recovered to the prediet levels 4 wk after the termination of soy consumption (38.6 ± 19.6 pg/ml; P = 0.66). A similar decrease of up to 56.6 and 14.4% was found for serum IL-1 and the mean percentage of blood monocytes during soy consumption, respectively, but not for IL-6. In cultures of monocytes or whole blood from postmenopausal women, soy isoflavones (genistein and daidzein, 10–1000 nM), tamoxifen (10–1000 nM), or 17ß-estradiol (0.1–10 nM) inhibited lipopolysaccharide (1 µg/ml)-induced TNF- production by up to 55.8%.

Conclusions: Isoflavones may be the active components in soy responsible for the decrease of TNF- found in postmenopausal women during a soy diet. This antiinflammatory effect of the isoflavones may be important in immune modulation and the prevention of bone loss and cancer.

This article has been cited by other articles:

				C. Nagata, K. Nakamura, K. Fujii, T. Kawachi, N. Takatsuka, S. Oba, and H. Shimizu Soy Isoflavone Intake Is Not Associated with the Development of Cedar Pollinosis in Adults J. Nutr., July 1, 2008; 138(7): 1372 - 1376. [Abstract] [Full Text] [PDF]

				L. Azadbakht, S. Atabak, and A. Esmaillzadeh Soy Protein Intake, Cardiorenal Indices, and C-Reactive Protein in Type 2 Diabetes With Nephropathy: A longitudinal randomized clinical trial Diabetes Care, April 1, 2008; 31(4): 648 - 654. [Abstract] [Full Text] [PDF]

				Y.-H. Chan, K.-K. Lau, K.-H. Yiu, S.-W. Li, H.-T. Chan, S. Tam, X.-O. Shu, C.-P. Lau, and H.-F. Tse Isoflavone intake in persons at high risk of cardiovascular events: implications for vascular endothelial function and the carotid atherosclerotic burden Am. J. Clinical Nutrition, October 1, 2007; 86(4): 938 - 945. [Abstract] [Full Text] [PDF]

				L. Azadbakht, M. Kimiagar, Y. Mehrabi, A. Esmaillzadeh, F. B. Hu, and W. C. Willett Soy Consumption, Markers of Inflammation, and Endothelial Function: A cross-over study in postmenopausal women with the metabolic syndrome Diabetes Care, April 1, 2007; 30(4): 967 - 973. [Abstract] [Full Text] [PDF]