Bark extract may reduce postmenopausal bone loss
MedWire News: Study findings show the butanolic fraction (BF) of Ulmus wallichiana stem bark is more effective at preventing postmenopausal bone loss in rats than the total ethanolic extract (TEE).
U. Wallichiana is a West Himalayan plant traditionally used for bone healing in India and the TEE of the plant has several C-glycosylated flavonoids that have been shown to promote in vitro osteoblast differentiation, explain Naibedya Chattopadhyay (Drug Research Institute, Lucknow, India) and co-workers.
To investigate further, the team examined the effects of the TEE, and its BF which contains enriched flavonoids on growing rats and ovariectomized rats.
Baby rats undergoing weaning and adult ovariectomized rats were fed TEE 750 mg/kg/day, BF 50 mg/kg/day, or vehicle treatment for 12 weeks, and examined for bone mineral density (BMD), biomechanical strength, histology, bone turnover and resorption markers, and other bone characteristics.
As reported in the journal Menopause, growing rats fed TEE or BF showed increased BMD, strength, and bone formation compared with controls, suggesting higher peak bone achievement.
Ovariectomized rats given TEE or BF showed greater BMD at several anatomical sites and improved bone strength and trabecular architecture compared with ovariectomized animals fed the vehicle treatment, and BMD levels comparable to sham-operated rats given the vehicle.
“These data suggest that TEE or BF treatments prevent bone loss induced by ovariectomization in both cortical and trabecular regions,” the team writes.
Furthermore, TEE and BF reduced bone turnover associated with removal of the ovaries, as demonstrated by significantly lower levels of osteocalcin and urinary type 1 collagen degredation products in ovariectomized rats given TEE or BF compared with vehicle.
The researchers note that using the enriched BF extract would give a human dose of around 480 mg per day for a 60-kg woman, an achievable level of dosing.
“Our data suggest that both TEE and BF are safe, promote peak bone achievement, and prevent ovariectomized-induced bone loss, thus raising the possibility of its use in menopausal osteoporosis,” Chattopadhyay et al conclude.
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By Lynda Williams