title: Effects of stinging nettle root extracts and their steroidal components on the Na+,K(+)-ATPase of the benign prostatic hyperplasia.
abstract: The effects of organic-solvent extracts of Urtica dioica (Urticaceae) on the Na+,K(+)-ATPase of the tissue of benign prostatic hyperplasia (BPH) were investigated. The membrane Na+,K(+)-ATPase fraction was prepared from a patient with BPH by a differential centrifugation of the tissue homogenate. The enzyme activity was inhibited by 10(-4)-10(-5) M of ouabain. The hexane extract, the ether extract, the ethyl acetate extract, and the butanol extract of the roots caused 27.6-81.5% inhibition of the enzyme activity at 0.1 mg/ml. In addition, a column extraction of stinging nettle roots using benzene as an eluent afforded efficient enzyme inhibiting activity. Steroidal components in stinging nettle roots, such as stigmast-4-en-3-one, stigmasterol, and campesterol inhibited the enzyme activity by 23.0-67.0% at concentrations ranging from 10(-3)-10(-6) M. These results suggest that some hydrophobic constituents such as steroids in the stinging nettle roots inhibited the membrane Na+,K(+)-ATPase activity of the prostate, which may subsequently suppress prostate-cell metabolism and growth.
authors.affiliation: Department of Clinical Pharmacology, Tokyo College of Pharmacy, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Hirano
authors.forename: M
authors.initials: M
authors.lastname: Homma
authors.forename: K
authors.initials: K
authors.lastname: Oka
mesh_terms: D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D010840:Phytosterols / Q000494:pharmacology*; D010936:Plant Extracts / Q000494:pharmacology*; D010946:Plants, Medicinal / Q000737:chemistry; D011470:Prostatic Hyperplasia / Q000188:drug therapy / Q000201:enzymology*; D000254:Sodium-Potassium-Exchanging ATPase / Q000187:drug effects*
chemical_list: D010840:Phytosterols; D010936:Plant Extracts; D000254:Sodium-Potassium-Exchanging ATPase