A new study published in the online open access journal BMC Biology suggests that disturbances in membrane cholesterol may be the mechanism by which prions cause neurodegeneration and could point to a role for cholesterol in other neurodegenerative diseases.
It is widely believed that prions (protein only infectious material) are the cause of rare progressive neurodegenerative disorders that affect both humans and animals. A prion is an infectious agent made solely of protein. However what is not known is how the prions damage brain cells (neurons).
Dr Clive Bate and colleagues from the Royal Veterinary College in the UK compared the amounts of protein and cholesterol in prion-infected neuronal cell lines and primary cortical neurons with uninfected controls. Protein levels were similar but the amount of total cholesterol (a mixture of free and esterified cholesterol) was significantly higher in the infected cell lines. The cholesterol balance was also affected: the amount of free cholesterol increased but that of cholesterol esters reduced, suggesting that prion infection affects cholesterol regulation.
The team attempted to reproduce the effects of prions on cholesterol levels, by stimulating cholesterol biosynthesis or by adding exogenous cholesterol. Both approaches resulted in increased amounts of cholesterol esters but not of free cholesterol. The free cholesterol is thought to affect the function of the cell membranes and to lead to abnormal activation of phospholipase A2, an enzyme implicated in the depletion of neurons in prion and Alzheimer’s disease.
Studies have recently shown that the controlling cholesterol levels within the brain is critical in limiting the development of neurodegenerative diseases such as Alzheimer’s, Parkinson’s and prion diseases, multiple sclerosis, and senile dementia.
This study now gives far more specific insight into the kind of mechanisms at work. Dr Bate stated: “Our observations raise the possibility that disturbances in membrane cholesterol induced by prions are major triggering events in the neuropathogenesis of prion diseases”.
Structure of a mitochondrial ATP synthase
19.11.2019 | Science For Life Laboratory
Mantis shrimp vs. disco clams: Colorful sea creatures do more than dazzle
19.11.2019 | University of Colorado at Boulder
Nanooptical traps are a promising building block for quantum technologies. Austrian and German scientists have now removed an important obstacle to their practical use. They were able to show that a special form of mechanical vibration heats trapped particles in a very short time and knocks them out of the trap.
By controlling individual atoms, quantum properties can be investigated and made usable for technological applications. For about ten years, physicists have...
An international team of scientists, including three researchers from New Jersey Institute of Technology (NJIT), has shed new light on one of the central mysteries of solar physics: how energy from the Sun is transferred to the star's upper atmosphere, heating it to 1 million degrees Fahrenheit and higher in some regions, temperatures that are vastly hotter than the Sun's surface.
With new images from NJIT's Big Bear Solar Observatory (BBSO), the researchers have revealed in groundbreaking, granular detail what appears to be a likely...
The Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM in Dresden has succeeded in using Selective Electron Beam Melting (SEBM) to...
Carbon nanotubes (CNTs) are valuable for a wide variety of applications. Made of graphene sheets rolled into tubes 10,000 times smaller than a human hair, CNTs have an exceptional strength-to-mass ratio and excellent thermal and electrical properties. These features make them ideal for a range of applications, including supercapacitors, interconnects, adhesives, particle trapping and structural color.
New research reveals even more potential for CNTs: as a coating, they can both repel and hold water in place, a useful property for applications like printing,...
If you've ever tried to put several really strong, small cube magnets right next to each other on a magnetic board, you'll know that you just can't do it. What happens is that the magnets always arrange themselves in a column sticking out vertically from the magnetic board. Moreover, it's almost impossible to join several rows of these magnets together to form a flat surface. That's because magnets are dipolar. Equal poles repel each other, with the north pole of one magnet always attaching itself to the south pole of another and vice versa. This explains why they form a column with all the magnets aligned the same way.
Now, scientists at ETH Zurich have managed to create magnetic building blocks in the shape of cubes that - for the first time ever - can be joined together to...
15.11.2019 | Event News
15.11.2019 | Event News
05.11.2019 | Event News
19.11.2019 | Physics and Astronomy
19.11.2019 | Social Sciences
19.11.2019 | Life Sciences