The Effects Of 6-Month Dried Plum Supplementation on Bone Health and Serum Cytokines in Men

Abstract

Abstract Objectives The purpose of this research was to investigate the effects of dried plum supplementation on modulating cytokines involved in macrophage polarization, osteoblast differentiation biomarkers, and functional outcomes of bone health in osteopenic men. Methods 60 men (Groups A, n = 24; B, n = 23; C, n = 13) between the ages of 55 and 80 with bone loss (T-score between −0.1 and −2.5 SD below the mean) were included in this study. Group A, B, and C consumed 100g, 50g, or 0g of dried plums daily for six months, respectively. All three groups also consumed a multivitamin containing 450 mg calcium and 800 IU vitamin D. Serum samples of 49 participants were analyzed at baseline, three months, and six months for concentrations of interleukin-6 (IL-6), interleukin-4 (IL-4), bone morphogenetic protein-2 (BMP-2), receptor activator of nuclear factor kappa-Β ligand RANKL, and tumor necrosis factor alpha (TNF-α). DXA scans were performed to measure site specific bone mineral density and bone mineral content at baseline, three months, and six months. Results Our results indicate that after six months there was no significant differences for anthropometric or body composition measurements. Neither group had a protective effect on bone density, however, there was a time dependent decrease in left hip BMD at 6 months compared to 3 months (P < 0.05) and radius BMD at 3 months compared to baseline (P < 0.05). A significant time*treatment effect was detected for concentrations of TNF-α for both DP groups compared to control. There were no significant differences for any other serum biomarkers assessed. Furthermore, there were no significant correlations between baseline BMD values and baseline concentrations of blood biomarkers. Conclusions The results indicate that 6 months of DP supplementation in men with bone loss does not have bone protective properties. Perhaps, the participants in our study did not have a sufficient degree of bone loss at baseline to experience benefits from DP. Furthermore, we demonstrated that DP attenuate increases in TNF-α, which is a cytokine that is involved in M1 macrophage polarization. Future research should focus on a wider range of baseline BMD scores, and should assess other biomarkers associated with macrophage polarization states to fully understand the relationship between the immune system and bone. Funding Sources USDA, Califorina Dried Plum