Tianying Wu, M.D., Ph.D.
University of Cincinnati
NIEHS Grant P30ES006096
An NIEHS grantee and colleagues report that biomarkers of oxidative stress are associated with hip fracture in postmenopausal women. If additional studies confirm these results, the biomarkers could help improve prediction of hip fracture, which is associated with substantial cost and a high risk of disability and death.
Oxidative stress occurs when the body insufficiently responds to reactive oxygen species. Environmental factors such as radiation and pollutants can add to the natural level of reactive oxygen species and overcome the body’s defenses. Studies in people have suggested that oxidative stress might be a risk factor for osteoporosis, but its relationship with fracture risk is poorly understood. To find out more, the researchers prospectively assessed oxidative stress by measuring fluorescent oxidation products (FlOP) in 996 women from the Nurses’ Health Study who were 60 or older at baseline blood collection between 1989 and 1990. FlOPs are markers of global oxidation burden and can be measured using a fluorescent spectrophotometer.
The researchers measured plasma FlOPs at three excitation/emission wavelengths (360/420 nm, 320/420 nm, and 400/475 nm), which each reflect products from different oxidative stress pathways. Women in the upper 30 percent of FlOP levels measured at 320/420 nm had 2.67 times the risk of hip fractures compared to those in the bottom 30 percent. No significant association was found between hip fracture and 360/420 nm or 400/475 nm FIOP measurements.Because FlOPs at 320/420 nm are generated when oxidative products react with DNA in the presence of metals, their strong association with hip fractures might reflect the coexisting effects of reactive oxygen species and heavy metals.
Citation: Yang S, Feskanich D, Willett WC, Eliassen AH, Wu T. 2014. Association between global biomarkers of oxidative stress and hip fracture in postmenopausal women: a prospective study. J Bone Miner Res; doi:10.1002/jbmr.2302 [Online 23 Jun 2014].