Changes in serum cytokines and vitamin D in Saudi postmenopausal women with osteoporosis

Accelerated bone loss has been observed in patients with inflammatory disorders, exacerbated with Vitamin D deficiency, whilst the impact of cytokines in the etiology of osteoporosis is unclear. However, the elucidation of this potential relationship could provide new insights to identify patients at early risk of osteoporosis as well as support the use of cytokine-based antibody therapies as potential interventions to reduce bone loss. The aim of the study was to determine the relationship between pro-and anti-inflammatory cytokines with bone loss in Saudi post-menopausal women with and without osteoporosis. Further to understand the relative importance of Vitamin D on changes in inflammatory cytokine status. For this study post-menopausal women with (n=101) and without osteoporosis (n=120) were recruited. Anthropometric was taken along with fasted blood to measure 25-hydroxyvitamin D [25(OH)D] and cytokines (TNF-α, TGF-β, IL-1β, IL-4, IL6, Leptin, adiponectin, resistin, PAI-1, Lipocalin). Data shows a significantly lower plasma TGF-β (P<0.001) and serum IL-4 (P<0.001) and a significantly higher serum resistin (P<0.001) in the osteoporosis patients compared with control. Vitamin D showed a significant negative association with resistin (P=0.024). The osteoporosis group displayed a pro-inflammatory state with elevated serum levels of IL-6, leptin, IL-1. Other Inflammatory biomarkers were not associated with vitamin in postmenopausal women. In conclusions, the present study showed that inflammatory factors, such as resistin, TGF-β and IL-4 may play an important role in bone metabolism in postmenopausal women with osteoporosis. It is important to understand the balance between pro and anti-inflammatory cytokines as the impact to lower anti-inflammatory cytokines may allow pro-inflammatory cytokines to have more of an impact, coupled with elevated resistin levels.