Nutritional supplement linked to bone metabolism improvement
MedWire News: A multi-component nutritional supplement including a hop extract and a plant alkaloid may boost healthy bone metabolism in postmenopausal women, US researchers suggest.
The team examined the benefits of the modified hop extract, rho iso-alpha acids (RIAA), which is used in beer and has proven anti-inflammatory effects in arthritis, and the isoquinoline alkaloid berberine, which is found in many medicinal plants and has been shown in rats to increase bone density and trabecular thickness and reduce osteoclast numbers.
For the study, 32 healthy postmenopausal women, aged an average of around 58 years, were recruited to the trial and asked to follow a Mediterranean-style , low-glycemic-load diet and take moderate aerobic exercise. Seventeen women were randomly assigned to receive placebo and 16 to take a nutritional supplement twice a day consisting of RIAA 200 mg, berberine sulfate trihydrate 100 mg, vitamin D3 500 IU, and vitamin K1 500 μg.
After 14 weeks of treatment, serum osteocalcin levels, an indicator of bone turnover, were significantly different between the groups, with a 31% drop from baseline in the women given the supplement versus a 19% increase in placebo-treated patients.
In addition, supplement-treated women experienced a 13% increase in their serum hydroxyvitamin D level from baseline, whereas controls experienced a significant 25% decrease.
Finally, both treatment groups experienced an increase in their low baseline serum levels of serum insulin growth factor (IGF)-1 toward normal levels, and the rise was significantly greater in supplement-treated women than in controls.
The researchers note in the Journal of Bone and Mineral Metabolism that normal IGF-1 levels are necessary for healthy osteoblast function, and that RIAA has been linked to greater improvements in metabolic syndrome in women compared with adhering to a Mediterranean-style low-glycemic-load diet. Although the participants of the current study did not have metabolic syndrome, the team notes that insulin resistance is common in older US women.
“Given our clinical findings, the overall vitamin D sufficiency at baseline, and our understanding of the mechanism of action of the ingredients in the nutraceutical, we believe it is likely that RIAA and berberine contributed the greatest influence on promoting bone health in this study,” write Joseph Lamb (MetaProteomics, LLC, Gig Harbour, Washington, USA) and co-workers.
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By Lynda Williams