Objective: Phthalates induce inflammation and are ubiquitously used in daily life. We aim to study the impact of di-(2-ethylhexyl) phthalate (DEHP) exposure on inflammation and osteoporosis in premenopausal and postmenopausal females.
Methods: Female 8-week-old C57BL/6JNarl mice received an ovariectomy (OVX) or a sham operation and were fed with DEHP or vehicle by oral gavage for 4 or 8 weeks. Their femurs were isolated for micro-computed tomography, and their serum was collected for inflammatory cytokine assays. Correlations between urinary phthalate metabolites and the lumbar spine bone mineral density (BMD) in premenopausal and postmenopausal volunteers were performed.
Results: Among the OVX mice treated for 4 weeks, significant lower bone volume, bone volume/tissue volume, and trabecular number but significant higher trabecular bone pattern factor and structure model index were identified in the mice treated with DEHP than with vehicle. The OVX mice treated with DEHP for 4 weeks had significantly higher serum interleukin (IL)-1β, IL-10, IL-17A, interferon (IFN)-γ, tumor necrosis factor (TNF)-α, and Dickkopf-1 levels than those treated with vehicle. The sham mice treated with DEHP for 8 weeks showed an impaired femur trabecular microstructure and had significantly higher serum IL-1β, IL-6, IL-10, IL-17A, IFN-γ, and TNF-α than those treated with vehicle. DEHP metabolites were inversely correlated with the BMD of premenopausal women and the T-score of postmenopausal women.
Conclusion: DEHP treatment in OVX and sham mice results in osteoporosis and impairs the microstructure of the femur trabecula through inflammation. Phthalate exposure negatively affects the bone mass in both premenopausal and postmenopausal women. Thus, long-term avoidance is suggested.
Keywords: bone mineral density; osteoporosis; ovariectomized mice; phthalates; premenopausal and postmenopausal women.
© 2022 Asia Pacific League of Associations for Rheumatology and John Wiley & Sons Australia, Ltd.