Effect of red clover isoflavones on cox-2 activity in murine and human monocyte/macrophage cells

• Published in: Nutrition and cancer 2004-01, Vol.49 (1), p.89-93
• Main Authors: Lam, A.N.C, Demasi, M, James, M.J, Husband, A.J, Walker, C
• Format: Article
• Language: English
• Subjects: Animals; Anticarcinogenic Agents - pharmacology; Biological and medical sciences; Cells, Cultured; Cyclooxygenase 2; Dietary Supplements; Dinoprostone - biosynthesis; Dose-Response Relationship, Drug; enzyme activity; Feeding. Feeding behavior; Fundamental and applied biological sciences. Psychology; Genistein - pharmacology; human health; human nutrition; Humans; isoflavones; Isoflavones - pharmacology; macrophages; Macrophages - enzymology; Medical sciences; Membrane Proteins; Metabolic diseases; Mice; monocytes; Monocytes - enzymology; phytochemicals; prostaglandin synthase; Prostaglandin-Endoperoxide Synthases - drug effects; Prostaglandin-Endoperoxide Synthases - metabolism; Thromboxane B2 - biosynthesis; Trifolium - chemistry; Trifolium pratense; Tumors; Vertebrates: anatomy and physiology, studies on body, several organs or systems
• ISSN: 0163-5581; 1532-7914
• DOI: 10.1207/s15327914nc4901_12

Long-term use of nonsteroidal anti-inflammatory drugs is associated with a reduction in the incidence of a range of cancers, the mechanism of which is thought to be cyclooxygenase (COX) inhibition. Because long-term ingestion of foods rich in isoflavones, such as legumes (beans, peas, lentils) has been associated with reduced cancer incidence, it was considered useful to examine the COX-inhibitory activities of individual isoflavones. Red clover dietary supplements also contain varying ratios of the 4 isoflavones commonly found in legume-based diets, namely, daidzein, genistein, formononetin, and biochanin. Using 2 separate cell assays, this study examined the ability of the isoflavones found in red clover to inhibit COX enzyme activity in both the murine macrophage cell line RAW 264.7 and human monocytes. Within the range of 1-40 micromolar in RAW 264.7 cells and 10-100 micromolar in human monocytes, isoflavones were able to reduce significantly the synthesis of prostaglandin E2 and/or thromboxane B2 (P < 0.001 to P < 0.05), indicating COX inhibition. Thus, it is possible that the lower rates of some cancers in populations with a high intake of dietary isoflavones is linked to their inhibition of COX activity.