A comparative study of the effects of genistein, estradiol and raloxifene on the murine skeletal system.
Genistein, a major phytoestrogen of soy, is considered a potential drug for prevention and treatment of postmenopausal osteoporosis. The aim of the present study was to compare the effects of genistein, estradiol and raloxifene on the skeletal system in vivo and in vitro. Genistein (5 mg/kg), estradiol (0.1 mg/kg) or raloxifene hydrochloride (5 mg/kg) were administered daily by a stomach tube to mature ovariectomized Wistar rats for 4 weeks. Bone mass, mineral and calcium content, macrometric parameters and mechanical properties were examined. Also the effects of genistein, estradiol and raloxifene (10(-9)-10(-7) M) on the formation of osteoclasts from neonatal mouse bone marrow cells and the activity of osteoblasts isolated from neonatal mouse calvariae were compared. In vivo, estrogen deficiency resulted in the impairment of bone mineralization and bone mechanical properties. Raloxifene but not estradiol or genistein improved bone mineralization. Estradiol fully normalized the bone mechanical properties, whereas genistein augmented the deleterious effect of estrogen-deficiency on bone strength. In vitro, genistein, estradiol and raloxifene inhibited osteoclast formation from mouse bone marrow cells, decreasing the ratio of RANKL mRNA to osteoprotegerin mRNA expression in osteoblasts. Genistein, but not estradiol or raloxifene, decreased the ratio of alkaline phosphatase mRNA to ectonucleotide pyrophosphatase phosphodiesterase 1 mRNA expression in osteoblasts. This difference may explain the lack of genistein effect on bone mineralization observed in ovariectomized rats in the in vivo study. Concluding, our experiments demonstrated profound differences between the activities of genistein, estradiol and raloxifene towards the osseous tissue in experimental conditions.
Sliwiński
Leszek
L
Department of Pharmacology, Medical University of Silesia, Sosnowiec, Poland.
Folwarczna
Joanna
J
Nowińska
Barbara
B
Cegieła
Urszula
U
Pytlik
Maria
M
Kaczmarczyk-Sedlak
Ilona
I
Trzeciak
Hanna
H
Trzeciak
Henryk I
HI
D000818:Animals; D001835:Body Weight / Q000187:drug effects; D015519:Bone Density / Q000187:drug effects; D001854:Bone Marrow Cells / Q000166:cytology / Q000187:drug effects; D001862:Bone Resorption / Q000235:genetics; D001842:Bone and Bones / Q000737:chemistry / Q000187:drug effects*; D002113:Calcification, Physiologic / Q000187:drug effects* / Q000235:genetics; D002118:Calcium / Q000032:analysis; D002452:Cell Count; D002478:Cells, Cultured; D004195:Disease Models, Animal; D004338:Drug Combinations; D004958:Estradiol / Q000494:pharmacology*; D004964:Estriol / Q000494:pharmacology; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D019833:Genistein / Q000494:pharmacology*; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D009929:Organ Size / Q000187:drug effects; D010006:Osteoblasts / Q000187:drug effects / Q000378:metabolism; D010010:Osteoclasts / Q000187:drug effects; D015663:Osteoporosis, Postmenopausal / Q000188:drug therapy / Q000503:physiopathology; D010052:Ovariectomy; D048789:Phytoestrogens / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism; D020849:Raloxifene Hydrochloride / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D020845:Selective Estrogen Receptor Modulators / Q000494:pharmacology; D013950:Thymus Gland / Q000187:drug effects; D014599:Uterus / Q000187:drug effects
D004338:Drug Combinations; D048789:Phytoestrogens; D012333:RNA, Messenger; D020845:Selective Estrogen Receptor Modulators; C044003:estradiol, estriol drug combination; D020849:Raloxifene Hydrochloride; D004958:Estradiol; D019833:Genistein; D004964:Estriol; D002118:Calcium