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 Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery
20.01.2017 | GSI Helmholtzzentrum für Schwerionenforschung GmbH

nachricht Seeking structure with metagenome sequences
20.01.2017 | DOE/Joint Genome Institute

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>