Effect of blueberry polyphenols on osteoclast

Bone is a dynamic tissue with osteoblasts and osteoclasts participating concomitantly in its remodeling process. Blueberries are a rich source of polyphenolic compounds and have been shown to be effective in decreasing incidence/symptoms of chronic inflammatory conditions. The purpose of this study was to assess the effect of blueberry polyphenols as a whole on osteoclasts by assessing markers for activity and differentiation. RAW 264.7 murine macrophage cells were cultured, differentiated into osteoclasts and treated with varying blueberry polyphenols doses. Levels of Tartrate Resistant Acid Phosphatases (TRAP), Nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1), cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) were determined. Blueberry polyphenols were shown to be effective by decreasing iNOS, COX-2 and TRAP levels. This study indicates that blueberry polyphenols decrease osteoclast activity through multiple mechanisms such as inflammatory mediators and key bone resorption enzymes which in turn cause a decrease in osteoclast function.