Oxidative stress is a significant predictor for hip fracture in postmenopausal women, according to new research led by University of Cincinnati (UC) epidemiologists.
The research, appearing online ahead of print in the Journal of Bone and Mineral Research, was led by Tianying Wu, MD, PhD, an assistant professor in the UC College of Medicine Department of Environmental Health, and Shuman Yang, a postdoctoral fellow in the department. They collaborated with researchers from the Harvard School of Public Health and Harvard Medical School.
"To our knowledge, this is the first prospective study among postmenopausal women demonstrating that oxidative stress was a significant predictor for hip fracture,” says Wu, the study’s corresponding author.
Oxidative stress is defined as physiological stress on the body that is caused by the cumulative damage done by free radicals, which are inadequately neutralized by antioxidants. Free radicals are unstable molecules that react with other substances in the human body to damage cells or organs.
Oxidative stress occurs naturally, but environmental factors such as natural and artificial radiation, toxins in air, food and water and miscellaneous sources such as tobacco smoke can add to the overall burden and defeat the body’s antioxidant defenses.
The researchers assessed oxidative stress by measuring fluorescent oxidation products (FlOP) in blood plasma. FlOP reflects a mixture of oxidation products from lipids, proteins and DNA and can be measured by a fluorescent spectrophotometer.
Researchers studied participants in the Nurses’ Health Study, which began in 1976 with funding from the National Institutes of Health (NIH). Participants are female nurses who periodically respond to questionnaires and submit samples.
The researchers studied 996 women aged 60 or older at baseline blood collection (1989-1990). Plasma FlOPs were measured at three excitation/emission wavelengths: 360/420 nm (nanometers), named as FlOP_360; 320/420 nm, named as FlOP_320; and 400-475 nm, named as FlOP_400.
FlOP_360 represents oxidation products that are generated from oxidized phospholipids or from lipid oxidation products reacting with proteins. FlOP_320 is formed when oxidation products such as lipid hydroperoxides, aldehydes and ketones react with DNA in the presence of metals. FlOP_400 reflects the interaction between malondialdehyde (a specific marker for lipid oxidation), proteins and phospholipids.
Of the three wavelengths, researchers found that baseline levels of FlOP_320 products predicted risk of future hip fracture in the study cohort. (No association was found with FlOP_360 and FlOP_400.) Increased FlOP_320 was associated with greater risk of hip fracture; women in the upper 30 percent of FlOP_320 readings were found to have 2.67 times the risk of hip fractures of those in the bottom 30 percent.
"Because FlOP_320 is generated in the presence of metals, its strong association with hip fractures may reflect the co-existing effect of reactive oxygen species and heavy metals,” says Wu, who notes that the other FlOP products can be generated without metals.
Hip fracture is associated with substantial cost, as well as higher risk of disability, co-morbidities and mortality than any other fractures. Current fracture risk assessment uses traditional risk factors such as age and presence of osteoporosis, but Wu sees FlOP_320 playing an important role in risk assessment.
"If our findings are confirmed in other studies, adding this marker into the existing fracture assessment model could improve the prediction of hip fracture in postmenopausal women,” she says.
The study was funded by grants from the American Heart Association, the NIH’s National Heart, Lung and Blood Institute and National Cancer Institute and the UC Center for Environmental Genetics, funded by the NIH’s National Institute of Environmental Health Sciences.
Keith Herrell | Eurek Alert!
Resolving the mystery of preeclampsia
21.10.2016 | Universitätsklinikum Magdeburg
New potential cancer treatment using microwaves to target deep tumors
12.10.2016 | University of Texas at Arlington
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.
Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
21.10.2016 | Health and Medicine
21.10.2016 | Information Technology
21.10.2016 | Materials Sciences