I wonder why no one has done anything with these results??? Seems like urtica dioica extract (with a high concentration of 3,4-divanillyltetrahydrofuran) would make a good additive to a product like M or Tribex.
Lignans from the roots of Urtica dioica and their metabolites bind to human sex hormone binding globulin (SHBG).
Schottner M, Gansser D, Spiteller G.
Lehrstuhl Organische Chemie I, Universitat Bayreuth, Germany.
Polar extracts of the stinging nettle (Urtica dioica L.) roots contain the ligans (+)-neoolivil, (-)-secoisolariciresinol, dehydrodiconiferyl alcohol, isolariciresinol, pinoresinol, and 3,4-divanillyltetrahydrofuran. These compounds were either isolated from Urtica roots, or obtained semisynthetically. Their affinity to human sex hormone binding globulin (SHBG) was tested in an in vitro assay. In addition, the main intestinal transformation products of plant lignans in humans, enterodiol and enterolactone, together with enterofuran were checked for their activity. All lignans except (-)-pinoresinol developed a binding affinity to SHBG in the in vitro assay. The affinity of (-)-3,4-divanillyltetrahydrofuran was outstandingly high. These findings are discussed with respect to potential beneficial effects of plant lignans on benign prostatic hyperplasia (BPH).
The effect of extracts of the roots of the stinging nettle (Urtica dioica) on the interaction of SHBG with its receptor on human prostatic membranes.
Hryb DJ, Khan MS, Romas NA, Rosner W.
Department of Medicine, St. Luke’s/Roosevelt Hospital Center, New York, N.Y. 10019.
Extracts from the roots of the stinging nettle (Urtica dioica) are used in the treatment of benign prostatic hyperplasia. The mechanisms underlying this treatment have not been elucidated. We set out to determine whether specific extracts from U. dioica had the ability to modulate the binding of sex hormone-binding globulin to its receptor on human prostatic membranes. Four substances contained in U. dioica were examined: an aqueous extract; an alcoholic extract; U. dioica agglutinin, and stigmasta-4-en-3-one. Of these, only the aqueous extract was active. It inhibited the binding of 125I-SHBG to its receptor. The inhibition was dose related, starting at about 0.6 mg/ml and completely inhibited binding at 10 mg/ml.