title: Antiosteoclastic activity of milk thistle extract after ovariectomy to suppress estrogen deficiency-induced osteoporosis.
abstract: Bone integrity abnormality and imbalance between bone formation by osteoblasts and bone resorption by osteoclasts are known to result in metabolic bone diseases such as osteoporosis. Silymarin-rich milk thistle extract (MTE) and its component silibinin enhanced alkaline phosphatase activity of osteoblasts but reduced tartrate-resistant acid phosphatase (TRAP) activity of osteoclasts. The osteoprotective effects of MTE were comparable to those of estrogenic isoflavone. Low-dose combination of MTE and isoflavone had a pharmacological synergy that may be useful for osteogenic activity. This study attempted to reveal the suppressive effects of MTE on bone loss. C57BL/6 female mice were ovariectomized (OVX) as a model for postmenopausal osteopenia and orally administered 10 mg/kg MTE or silibinin for 8 weeks. The sham-operated mice served as estrogen controls. The treatment of ovariectomized mice with nontoxic MTE and silibinin improved femoral bone mineral density and serum receptor activator of nuclear factor- κB ligand/osteoprotegerin ratio, an index of osteoclastogenic stimulus. In addition, the administration of MTE or silibinin inhibited femoral bone loss induced by ovariectomy and suppressed femoral TRAP activity and cathepsin K induction responsible for osteoclastogenesis and bone resorption. Collectively, oral dosage of MTE containing silibinin in the preclinical setting is effective in preventing estrogen deficiency-induced bone loss.
authors.affiliation: Department of Food and Nutrition, Hallym University, Chuncheon, Kangwon-do, Republic of Korea.
authors.forename: Jung-Lye
authors.initials: JL
authors.lastname: Kim
authors.forename: Yun-Ho
authors.initials: YH
authors.lastname: Kim
authors.forename: Min-Kyung
authors.initials: MK
authors.lastname: Kang
authors.forename: Ju-Hyun
authors.initials: JH
authors.lastname: Gong
authors.forename: Seoung-Jun
authors.initials: SJ
authors.lastname: Han
authors.forename: Young-Hee
authors.initials: YH
authors.lastname: Kang
mesh_terms: D000135:Acid Phosphatase / Q000378:metabolism; D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D056657:Cathepsin K / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D004958:Estradiol / Q000097:blood; D004967:Estrogens / Q000172:deficiency*; D005260:Female; D005269:Femur / Q000187:drug effects / Q000201:enzymology / Q000473:pathology; D007527:Isoenzymes / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D020944:Silybum marianum / Q000737:chemistry*; D009929:Organ Size / Q000187:drug effects; D010006:Osteoblasts / Q000201:enzymology; D010010:Osteoclasts / Q000187:drug effects / Q000201:enzymology / Q000473:pathology*; D010012:Osteogenesis / Q000187:drug effects; D010024:Osteoporosis / Q000097:blood / Q000188:drug therapy* / Q000473:pathology*; D010052:Ovariectomy; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use*; D000077385:Silybin; D012838:Silymarin / Q000494:pharmacology / Q000627:therapeutic use; D013025:Glycine max / Q000737:chemistry; D000071681:Tartrate-Resistant Acid Phosphatase; D014599:Uterus / Q000187:drug effects / Q000473:pathology
chemical_list: D004967:Estrogens; D007527:Isoenzymes; D010936:Plant Extracts; D012838:Silymarin; D000077385:Silybin; D004958:Estradiol; D000469:Alkaline Phosphatase; D000135:Acid Phosphatase; C000605511:Acp5 protein, mouse; D000071681:Tartrate-Resistant Acid Phosphatase; D056657:Cathepsin K