Physiologic Actions

According to research scientists writing in The Journal of Progressive Drug Research, lignans have now been shown to influence not only sex-hormone metabolism and biological activity but also intracellular enzymes, protein synthesis, growth factor action, malignant cell proliferation, differentiation and angiogenesis, making them strong candidates as natural cancer chemo-preventative compounds.

Scientific research has revealed at least twelve significant actions of lignans in the body, one of which is the capacity to block and occupy human estrogen receptor sites.

1. Lignans act as anti-estrogens by competing with estrogen for estrogen receptor binding sites, and thereby inhibit the growth and proliferation of hormone-dependant cells.
2. Lignans inhibit the binding of estrogen to its primary protein carrier - Sex Hormone Binding Globulin (SHBG) thereby accelerating the bodies metabolic clearance of estrogen.
3. Sex Hormone Binding Globulin escorts lignans to target cells where they can inhibit estrogen production.
4. Lignans are potent anti-oxidants, and once carried to target cells by SHBG may protect them from cancer causing peroxides.
5. Lignans inhibits the enzyme (aromatase) from converting weaker steroids to estrogen, and thus may reduce the amount of circulating estrogen.
6. Lignans inhibit the enzyme (5-alpha-reductase) that converts testosterone to metabolites that are potentially five-times more powerful than testosterone at promoting prostate cancer.
7. Lignans inhibit the enzyme (17²-hydroxysteroid) an enzyme responsible for the conversion of testosterone to androstenedione. Androstenedione is a precursor to estrone, implicated in ovarian cancer.
8. Lignans inhibit the enzyme (protein tyrosine kinase) associated with retro-viral cancer-causing genes.
9. Lignans demonstrate cytotoxic (cell killing) effects on non-estrogen dependant human breast cancer cells and promyelocytic leukemic cell lines.
10. Lignans inhibits the binding of estrogens to alpha-fetoprotein, a protein characteristic of cancer development.
11. Lignans inhibit angiogenesis, the development of capillary blood vessels that provide cancer cells with a blood supply and nutrients.
12. Lignans decrease lifetime exposure to estrogen by lengthening the luteal phase of the menstrual cycle

References

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