PPARa, which stands for Peroxisome Proliferator Activated Receptor alpha, is a receptor that can be found in numerous tissues, including liver, heart and intestine. It reacts to certain drugs by turning on specific genes, yet can also respond to fatty acids and fatty acid look-a-likes. Activation of PPARa is known to lower levels of triglycerides in blood, providing a rationale for their use in patients suffering from altered blood lipid levels.
In their nutrigenomics study, the research team led by Linda Sanderson fed mice individual fatty acids in the form of synthetic triglycerides. Using a technique called microarray, which allows for monitoring the expression of thousands of genes simultaneously, they were able to determine exactly which genes are turned on in the mouse liver and which ones are turned off. The researchers found that the fatty acid DHA has the most significant impact and changes the expression of around 600 genes. DHA is found in fatty fish and fish oil and has been associated with numerous health benefits, including lowering of plasma triglycerides and decreasing blood clotting.
The most remarkable about the study is that the effects of unsaturated fatty acids are almost entirely lost in mice that lack the PPARa receptor.From the literature it is known that numerous receptors can supposedly bind fatty acids and turn on genes. Most of these receptors belong to the family of the so called 'nuclear hormone receptors', which includes receptors that bind steroid hormones and fat soluble vitamins. However, it was unknown how important they are in an actual living animal. The new data show that PPARa is by far the most important.
Many of the genes that are turned on by unsaturated fatty acids are involved in breaking down fatty acids to generate energy. This mechanism likely protects the liver cell from build-up of unsaturated fatty acids, which is harmful to the cell. It also likely accounts for the lowering of plasma triglycerides by fish oil.
Until now, all nutritional interventions with dietary fat in either mice or human subjects involved a mixture of fatty acids. For that reason, it has been very difficult to draw clear conclusions about the effects of individual fatty acids. The mixed nutritional/pharmacological intervention with synthetic triglycerides pursued by Sanderson and colleagues represents a creative and novel way to study the molecular effects of dietary fat. They expect that their approach will set a new standard for many future nutrigenomic studies.
Jac Niessen | alfa
Neutrons produce first direct 3D maps of water during cell membrane fusion
21.09.2018 | DOE/Oak Ridge National Laboratory
Narcolepsy, scientists unmask the culprit of an enigmatic disease
20.09.2018 | Universitätsspital Bern
The building blocks of matter in our universe were formed in the first 10 microseconds of its existence, according to the currently accepted scientific picture. After the Big Bang about 13.7 billion years ago, matter consisted mainly of quarks and gluons, two types of elementary particles whose interactions are governed by quantum chromodynamics (QCD), the theory of strong interaction. In the early universe, these particles moved (nearly) freely in a quark-gluon plasma.
This is a joint press release of University Muenster and Heidelberg as well as the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt.
Then, in a phase transition, they combined and formed hadrons, among them the building blocks of atomic nuclei, protons and neutrons. In the current issue of...
Thin-film solar cells made of crystalline silicon are inexpensive and achieve efficiencies of a good 14 percent. However, they could do even better if their shiny surfaces reflected less light. A team led by Prof. Christiane Becker from the Helmholtz-Zentrum Berlin (HZB) has now patented a sophisticated new solution to this problem.
"It is not enough simply to bring more light into the cell," says Christiane Becker. Such surface structures can even ultimately reduce the efficiency by...
A study in the journal Bulletin of Marine Science describes a new, blood-red species of octocoral found in Panama. The species in the genus Thesea was discovered in the threatened low-light reef environment on Hannibal Bank, 60 kilometers off mainland Pacific Panama, by researchers at the Smithsonian Tropical Research Institute in Panama (STRI) and the Centro de Investigación en Ciencias del Mar y Limnología (CIMAR) at the University of Costa Rica.
Scientists established the new species, Thesea dalioi, by comparing its physical traits, such as branch thickness and the bright red colony color, with the...
Scientists have succeeded in observing the first long-distance transfer of information in a magnetic group of materials known as antiferromagnets.
An international team of researchers has mapped Nemo's genome, providing the research community with an invaluable resource to decode the response of fish to...
21.09.2018 | Event News
03.09.2018 | Event News
27.08.2018 | Event News
21.09.2018 | Physics and Astronomy
21.09.2018 | Life Sciences
21.09.2018 | Event News