ESTROGEN AND PROGESTIN BIOACTIVITY OF FOODS, HERBS, AND SPICES

In this study we report on the content and bioactivity of plant (phyto ) estrogens and progestins in various foods, herbs, and spices, before and after human consumption. Over 150 herbs traditionally used by her balists for treating a variety of health problems were extracted and t ested for their relative capacity to compete with estradiol and proges terone binding to intracellular receptors for progesterone (PR) and es tradiol (ER) in intact human breast cancer cells. The six highest ER-b inding herbs that are commonly consumed were soy, licorice, red clover , thyme, tumeric, hops, and verbena. The six highest PR-binding herbs and spices commonly consumed were oregano, verbena, tumeric, thyme, re d clover and damiana. Some of the herbs and spices found to contain hi gh phytoestrogens and phytoprogestins were further tested for bioactiv ity based on their ability to regulate cell growth rate in ER (+) and ER (-) breast cancer cell lines and to induce or inhibit the synthesis of alkaline phosphatase, an end product of progesterone action, in PR (+) cells, In general, we found that PR-binding herbal extracts were agonists, much like estradiol, whereas PR-binding extracts, were neutr al or antagonists. The bioavailability of phytoestrogens and phytoprog estins in vivo were studied by quantitating the PR-binding and PR-bind ing capacity of saliva following consumption of soy milk, exogenous pr ogesterone, medroxyprogesterone acetate, or wild mexican yam products containing diosgenin. Soy milk caused a dramatic increase in saliva PR -binding components without a concommitant rise in estradiol. Consumpt ion of PR-binding herbs increased the progestin activity of saliva, bu t there were marked differences in bioactivity. In summary, we have de monstrated that many of the commonly consumed foods, herbs, and spices contain phytoestrogens and phytoprogestins that act as agonists and a ntagonists in vivo.