The study appeared in the June 2007 issue of Diabetes Care.
Flavonoids suppress destructive oxygen free radicals -- also known as reactive oxygen species, or ROS. An overabundance of free radicals can damage all components of the cell, including proteins, fats and DNA, contributing to the development of many chronic diseases, including heart disease and stroke as well as diabetes.
"Many major diseases are associated with oxidative stress and inflammation in the arterial wall, so the search for foods that are least likely to cause these conditions must be pursued," said Paresh Dandona, M.D., Ph.D., head of the Diabetes-Endocrinology Center of Western New York and senior author on the study.
"Our previous work has shown that 300 calories of glucose induces ROS and other proinflammatory responses," said Dandona, who is Distinguished Professor of Medicine in the UB School of Medicine and Biomedical Sciences.
"We hypothesized that 300 calories-worth of orange juice or of fructose would induce less oxidative stress and inflammation than caused by the same amount of calories from glucose."
The resulting study involved 32 healthy participants between the ages of 20 and 40, who were of normal weight, with a body mass index of 20-25 kg/m2. Participants were assigned randomly and evenly into four groups, who would drink the equivalent of 300 calories-worth of glucose, fructose, orange juice or saccharin-sweetened water.
Fasting blood samples were taken before the test and at 1, 2 and 3 hours after a 10-minute period to consume the drinks.
Results showed a significant increase in ROS within 2 hours in samples from the glucose group but not in those from the fructose, orange juice or water group.
"We were intrigued by the fact that there was no increase in ROS or inflammation following orange juice consumption, even though its glucose concentration was the same as in participants in the glucose group," said Dandona. "This raised the question of what in the juice was responsible for suppressing ROS generation: flavonoids and vitamin C or fructose?"
An additional round of test on the samples showed that neither fructose nor vitamin C suppressed the oxygen free radicals. However the two types of flavonoids in orange juice -- hesperetin and naringenin -- inhibited ROS generation by 52 percent and 77 percent, respectively.
"Our data are relevant to patients with diabetes," said Dandona, "because stress from ROS and inflammation are increased significantly in this population and may contribute to development of atherosclerosis. Clearly the choice of foods that either don't increase or actually decrease oxidative and inflammatory stress is important.
"The search for safe non-inflammatory foods and diets must continue," Dandona stressed, "especially since obesity, being overweight and type 2 diabetes are associated with oxidative stress and inflammation, and more than 60 percent of U.S. population is affected by these conditions."
The University at Buffalo is a premier research-intensive public university, the largest and most comprehensive campus in the State University of New York. UB's more than 27,000 students pursue their academic interests through more than 300 undergraduate, graduate and professional degree programs. Founded in 1846, the University at Buffalo is a member of the Association of American Universities. The School of Medicine and Biomedical Sciences is one of five schools that constitute UB's Academic Health Center.
Lois Baker | EurekAlert!
Researchers release the brakes on the immune system
18.10.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn
Norovirus evades immune system by hiding out in rare gut cells
12.10.2017 | University of Pennsylvania School of Medicine
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
18.10.2017 | Materials Sciences
18.10.2017 | Physics and Astronomy
18.10.2017 | Physics and Astronomy