The breakdown of bone is triggered by osteoclast cells - large cells in the bone marrow. Osteoclasts are actually a type of immune system cell called a macrophage. When the immune system releases a chemical messenger known as Interleukin-1beta (IL-1beta), the IL-1beta signals the osteoclasts to breakdown bone. IL-1beta is a potent stimulator of the breakdown of bone and it is implicated in osteoporosis and in periodontal bone loss.
Researchers surmised that one of the ways that the soy isoflavone Genestein protects bone density is through the inhibition of IL-1beta. In this study rat bone cells were cultured in different combinations with or without Genestein and IL-1beta. It was found that the Genestein decreased the ability of IL-1beta to cause bone demineralization. The study was conducted at the Department of Oral Pathology, Peking University School of Stomatology, and is published in the December 18th, 2004 issue of the Journal of Peking University Health Sciences.
In Asian countries where the women consume soy products there is a low incidence of breast cancer. Soy isoflavones have cancer preventing effects that work through inhibiting the formation of new cancer cells (proliferation), inhibiting the formation of blood vessels that feed a cancerous tumor (angiogenesis), and stimulating the death of breast cancer cells (apoptosis).
Cancer metastasis is the spread of cancer from one part of the body to another. Metastasis depends on overcoming the adhesion of blood vessel cells allowing the cancer cell to enter and exit the blood stream. The cancer cells travel or migrate to a distant site and invade and colonize this tissue. Different soy derivatives were tested on highly invasive breast cancer cells. The ability of the cancer cells to break into the blood circulation and travel (adhesion and migration) to distant sites was inhibited by both Genestein and Daidzein. The study was conducted at the Cancer research Laboratory, Methodist research Institute, in Indianapolis, and is published in the November 2004 issue of the International journal of Oncology.