Naringenin Found in Grapefruit Prevents Obesity,
Blocks Insulin Resistance in Mice
Concentrations of the citrus-derived flavonoid in
study are at higher levels than available from dietary
components
July 14, 2009 - A flavonoid derived from citrus
fruit has shown tremendous promise for senior citizens in new research
with mice by preventing weight gain and other
signs of metabolic syndrome which can lead to Type 2 Diabetes and
increased risk of cardiovascular disease.
The study, led by Murray Huff of the Robarts
Research Institute at The University of Western Ontario looked at a
flavonoid (plant-based bioactive molecule) called naringenin. The
findings are published online in the journal Diabetes.
In the study, one group of mice was fed a high-fat
(western) diet to induce the symptoms of metabolic syndrome.
A second group was fed the exact same diet and
treated with naringenin.
Naringenin corrected the elevations in triglyceride
and cholesterol, prevented the development of insulin resistance and
completely normalized glucose metabolism.
The researchers found it worked by genetically
reprogramming the liver to burn up excess fat, rather than store it.
"Furthermore, the marked obesity that develops in
these mice was completely prevented by naringenin," says Huff, Director
of the Vascular Biology Research Group at Robarts and Professor of
Medicine and Biochemistry at the Schulich School of Medicine &
Dentistry.
"What was unique about the study was that the
effects were independent of caloric intake, meaning the mice ate exactly
the same amount of food and the same amount of fat.
There was no suppression of appetite or decreased
food intake, which are often the basis of strategies to reduce weight
gain and its metabolic consequences."
While grapefruit has long been linked to weight
loss diets, the concentrations of the citrus-derived flavonoid being
studied are at higher levels than you could get from dietary components.
"We are examining the pharmacological properties of
naringenin," explains Huff.
"The next step is to find out if naringenin
prevents heart disease in animal models and to explore the feasibility
of clinical trials to determine its safety and efficacy in humans."
This study investigated naringenin's preventative
properties, but Huff is also investigating whether it can treat obesity
and other existing metabolic problems.
"These studies show naringenin, through its
insulin-like properties, corrects many of the metabolic disturbances
linked to insulin resistance and represents a promising therapeutic
approach for metabolic syndrome."
The co-first authors on the paper are Erin
Mulvihill and Emma Allister. The research was funded primarily by the
Heart and Stroke Foundation of Ontario.
July 14, 2009 - A flavonoid derived from citrus
fruit has shown tremendous promise for senior citizens in new research
with mice by preventing weight gain and other
signs of metabolic syndrome which can lead to Type 2 Diabetes and
increased risk of cardiovascular disease.