The Role of Prunes in Modulating Inflammatory Pathways to Improve Bone Health in Postmenopausal Women

Abstract The prevalence of osteoporosis among women aged 50 years and older is expected to reach 13.6 million by 2030. Alternative non-pharmaceutical agents for osteoporosis including nutritional interventions are becoming increasingly popular. Prunes (dried plums) (Prunus domestica L.) have been studied as a potential whole food dietary intervention to mitigate bone loss in preclinical models of osteoporosis and in osteopenic postmenopausal women. Sixteen preclinical studies using in vivo rodent models of osteopenia or osteoporosis have established that dietary supplementation with prunes confers osteoprotective effects both by preventing and reversing bone loss. Increasing evidence from ten studies suggests that in addition to anti-resorptive effects, prunes exert anti-inflammatory and antioxidant effects. Ten preclinical studies have found that prunes and/or their polyphenol extracts decrease malondialdehyde and nitric oxide secretion, increase antioxidant enzyme expression, or suppress NF-κB activation and pro-inflammatory cytokine production. Two clinical trials have investigated the impact of dried plum consumption (50–100g/day for 6–12 months) on bone health in postmenopausal women and demonstrate promising effects on bone mineral density and bone biomarkers. However, less is known about the impact of prune consumption on oxidative stress and inflammatory mediators in humans and their possible role in modulating bone outcomes. In this review, the current state of knowledge on the relationship between inflammation and bone health is outlined. Findings from preclinical and clinical studies that have assessed the effect of prunes on oxidative stress, inflammatory mediators, and bone outcomes are summarized, and evidence supporting a potential role of prunes in modulating inflammatory and immune pathways is highlighted. Key future directions to bridge the knowledge gap in the field are proposed.