Scientists at the Southwest Foundation for Biomedical Research (SFBR) have found a gene that causes high levels of bad cholesterol to accumulate in the blood as a result of a high-cholesterol diet.
Researchers studied a strain of laboratory opossums developed at SFBR that has normal blood levels of “bad” low-density lipoprotein (LDL) cholesterol when fed a standard low-cholesterol diet, but extremely elevated levels of LDL cholesterol when fed a high-cholesterol diet. These high-responding opossums are used to identify the genes and the underlying mechanisms that control response to dietary cholesterol.
“This research will improve our understanding of cholesterol metabolism and may shed light on why some people have high levels of bad cholesterol in blood while others do not when they consume cholesterol-enriched diets,” said John L. VandeBerg, Ph.D., SFBR’s chief scientific officer and senior author on the paper. Published in the October issue of the Journal of Lipid Research, the work was funded by the National Institutes of Health and the Robert J. Kleberg, Jr. and Helen C. Kleberg Foundation.
The study involved analyzing various lipids, or fats, in blood and bile to find differences in cholesterol metabolites, sequencing candidate genes of interest to find mutations, and determining the impact of each mutation by genetic analyses. This led to the discovery that the ABCB4 gene, which encodes a protein known to transport fats from the liver into bile to facilitate excretion of cholesterol from the body, is defective in the high responders. Malfunction of the ABCB4 protein was found to impair cholesterol excretion, causing bad cholesterol to accumulate in the blood when a high-cholesterol diet is consumed.
“This is the first report to show that ABCB4 has a role in controlling blood cholesterol levels in response to dietary cholesterol in an animal model,” said VandeBerg.
The next step is to determine if any ABCB4 mutations have an effect on levels of LDL cholesterol in humans who consume a high cholesterol diet. “If we can identify early in life those people who are going to be adversely affected by consumption of high levels of cholesterol, we can encourage their parents and them to receive individually tailored counseling to establish dietary habits that protect them from cardiovascular disease,” VandeBerg said.
Co-authors on the paper were Jeannie Chan, Ph.D., Michael C. Mahaney, Ph.D., Rampratap S. Kushwaha, Ph.D., and Jane F. VandeBerg in SFBR’s Department of Genetics. John VandeBerg can be reached through Joe Carey, SFBR’s Vice President for Public Affairs at 210-258-9437.
SFBR is one of the world's leading independent biomedical research institutions dedicated to advancing health worldwide through innovative biomedical research. Located on a 200-acre campus on the northwest side of San Antonio, Texas, SFBR partners with hundreds of researchers and institutions around the world, targeting advances in the fight against cardiovascular disease, diabetes, obesity, cancer, psychiatric disorders, problems of pregnancy, AIDS, hepatitis, malaria, parasitic infections and a host of other infectious diseases. For more information on SFBR, go to www.sfbr.org.
Joseph Carey | Newswise Science News
Pollen taxi for bacteria
18.07.2018 | Technische Universität München
Biological signalling processes in intelligent materials
18.07.2018 | Albert-Ludwigs-Universität Freiburg im Breisgau
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
18.07.2018 | Life Sciences
18.07.2018 | Life Sciences
18.07.2018 | Information Technology