Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The reason for mammals' ageing lies in the brain

21.05.2007
To date, there are two basic concepts of reasons for ageing. The first one is death as a result of damage accumulation, and the second is death as a suicide program. There are multiple arguments in favour of both concepts.

A new – astrocytic – hypothesis has been put forward by Aleksei Boyko, Ukrainian researcher, specialist of the National Agrarian University of Ukraine. In the framework of this hypothesis, ageing is treated as a result of changes in cerebrum cells. The key role is played by transmutation of cells of the radial neuroglia into stellate cells - astrocytes. Since such cell transmutation is a programmed process, the researcher is inclined to the opinion that ageing and following death have been programmed.

The researcher analyzed and compared animals with different ageing rates, and noticed that the majority of reptile, fish and amphibian species which grow old rather slowly have a very high regenerative activity of neural tissue. In other words, these species are able to quickly eliminate nervous system damage and replace extinct nerve cells (neurons). Mammals and birds have almost fully lost the regenerative capacity of the neural tissue, with new neurons formed only in certain parts of the cerebrum, for example, in the walls of the lateral ventricles of the hippocampus. Neuron predecessors – neuroblasts – migrate into various parts of the brain via radial neuroglia fibres, and turn into full-fledged neurons to replace extinct or damaged cells.

The researchers have found out that the mammals undergo changes during their life, with gradual transformation of radial neuroglia cells and transmutation into astrocytes. The astrocytes do not allow neuron predecessors to migrate to the required areas. Thus, renovation of brain cells becomes impossible, and brain cells, having lost their vital resource, ultimately mortify. Such age-specific brain changes undoubtedly cause changes to other internal and organ systems of the organism, with vascular derangements, hormonal status change, brygmus, alopecia, intercellular collagen accumulation, among the common signs of ageing. In contrast to mammals, amphibians such as fish and reptiles preserve their radial neuroglia cells throughout the life cycle, and ageing happens more slowly.

... more about:
»Neuroglia »Neuron »ageing »astrocyte

According to the researchers' astrocyte hypothesis, this is a probable ageing mechanism. They believe that it is the presence or absence of radial neuroglia cells that determines the life span.

Nadezda Markina | alfa
Further information:
http://www.informnauka.ru

Further reports about: Neuroglia Neuron ageing astrocyte

More articles from Life Sciences:

nachricht Link Discovered between Immune System, Brain Structure and Memory
26.04.2017 | Universität Basel

nachricht Researchers develop eco-friendly, 4-in-1 catalyst
25.04.2017 | Brown University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Scientist invents way to trigger artificial photosynthesis to clean air

26.04.2017 | Materials Sciences

Ammonium nitrogen input increases the synthesis of anticarcinogenic compounds in broccoli

26.04.2017 | Agricultural and Forestry Science

SwRI-led team discovers lull in Mars' giant impact history

26.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>