Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Increased Blood Flow triggers Liver Regeneration

04.10.2018

The liver is one of the few human organs that completely regenerates within a few weeks after more than half of the organ has been removed. Within the framework of the Collaborative Research Center 974 and with support from the German Center for Diabetes Research (DZD e.V.), scientists at the German Diabetes Center (DDZ), in cooperation with colleagues from HHU and Düsseldorf University Hospital (UKD) showed for the first time that increased blood flow through the small blood vessels of the liver triggers the release of signals from cells of these vessels, thus promoting liver growth. The results are published in the current issue of Nature.

The liver is one of the most important human organs. It is essential for metabolism, blood detoxification and the functioning of the immune system. Moreover, the liver is the only organ which can fully regenerate its cell mass within a few weeks after more than half of the organ has been removed.


An illustration of an artificially stained blood vessel is shown. It is a scanning electron micrograph of a hepatic blood vessel.

The image was taken and edited by Dr. Daniel Eberhard (Institute of Metabolic Physiology, HHU) and S. Köhler (Center for Advanced Imaging, HHU).

The researchers led by Professor Eckhard Lammert have discovered that it is due to increased blood flow and subsequent dilation of the liver vasculature that the liver receives signals for growth. The signals come from the cells of the blood vessels that react to the mechanical stimulation. The publication is based on the findings published in 2001 that blood vessels affect organs in their function and growth (Lammert et al., Science 2001).

"In our study of the liver and its blood vessels, we identified an important trigger for organ growth. For the first time, we were able to show that blood flow and vasodilatation release growth-promoting signals from blood vessels," said Professor Eckhard Lammert, director of the Institute for Beta Cell Biology at the German Diabetes Center (DDZ) and head of the Institute for Metabolic Physiology at Heinrich Heine University Düsseldorf.

"In the future, these exciting results could also become important for the understanding and treatment of fatty liver disease in obesity and diabetes," added Professor Michael Roden, scientific director and board member of the German Diabetes Center and director of the Department of Endocrinology and Diabetology at Düsseldorf University Hospital.“

The research results are of great importance for understanding the complex processes involved in liver regeneration and its disorders,“ said Professor Dieter Häussinger, director of the Department of Gastroenterology, Hepatology and Infectious Diseases at Düsseldorf University Hospital and spokesperson of the Collaborative Research Center 974.

Experimental Procedure

The molecular causes of this organ regeneration are the subject of a study published by Düsseldorf scientists in the journal Nature (Lorenz et al., Nature 2018). Specifically, the scientists were able to show that increased blood flow through the liver leads to the release and activation of growth signals from blood vessels.

One of these signals is the hepatocyte growth factor (HGF), which is particularly important for the growth and survival of liver cells. The endothelial cells of the blood vessels recognize the increased blood flow through the liver by means of so-called integrins.

These are cell surface proteins that connect the extracellular matrix to the cytoskeleton and are able to activate other receptors such as the vascular endothelial growth factor receptor-3 (VEGFR3). The activation of the β1 integrin (a subunit of the integrins) due to the increased blood flow leads in endothelial cells to the activation of VEGFR3 and the activation and release of growth factors such as HGF. The latter induce the growth of the liver.

As soon as the liver has grown to its normal size and new blood vessels have formed, a normal amount of blood per endothelial cell flows through the liver again. This normal mechanical stimulation of the endothelial cells could explain why the liver stops growing. The scientists postulate that this molecular mechanism causes the liver to grow as soon as its organ size is reduced and then to stop growing when it is restored.

Wissenschaftliche Ansprechpartner:

Prof. Dr. Eckhard Lammert
Institut für Stoffwechselphysiologie
Heinrich-Heine-Universität Düsseldorf
Universitätsstraße 1
40225 Düsseldorf
Tel.: +49 211 81-13234

Originalpublikation:

Lorenz L, Axnick J, Buschmann T, Henning C, Urner S, Fang S, Nurmi H, Eichhorst N, Holtmeier R, Bódis K, Hwang JH, Müssig K, Eberhard D, Stypmann J, Kuss O, Roden M, Alitalo K, Häussinger D, Lammert E. Mechanosensing by β1 integrin induces angiocrine signals for liver growth and survival. Nature. 2018 Sep 26. doi: 10.1038/s41586-018-0522-3.

Weitere Informationen:

https://figshare.com/s/f7ceb9d5980d10084ad8
http://ddz.uni-duesseldorf.de/en/

Christina Becker | idw - Informationsdienst Wissenschaft

Further reports about: Diabetes Regeneration blood flow blood vessels endothelial cells liver

More articles from Life Sciences:

nachricht Blocking the iron transport could stop tuberculosis
02.04.2020 | University of Zurich

nachricht Discovery of life in solid rock deep beneath sea may inspire new search for life on Mars
02.04.2020 | University of Tokyo

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A sensational discovery: Traces of rainforests in West Antarctica

90 million-year-old forest soil provides unexpected evidence for exceptionally warm climate near the South Pole in the Cretaceous

An international team of researchers led by geoscientists from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) have now...

Im Focus: Blocking the Iron Transport Could Stop Tuberculosis

The bacteria that cause tuberculosis need iron to survive. Researchers at the University of Zurich have now solved the first detailed structure of the transport protein responsible for the iron supply. When the iron transport into the bacteria is inhibited, the pathogen can no longer grow. This opens novel ways to develop targeted tuberculosis drugs.

One of the most devastating pathogens that lives inside human cells is Mycobacterium tuberculosis, the bacillus that causes tuberculosis. According to the...

Im Focus: Physicist from Hannover Develops New Photon Source for Tap-proof Communication

An international team with the participation of Prof. Dr. Michael Kues from the Cluster of Excellence PhoenixD at Leibniz University Hannover has developed a new method for generating quantum-entangled photons in a spectral range of light that was previously inaccessible. The discovery can make the encryption of satellite-based communications much more secure in the future.

A 15-member research team from the UK, Germany and Japan has developed a new method for generating and detecting quantum-entangled photons at a wavelength of...

Im Focus: Junior scientists at the University of Rostock invent a funnel for light

Together with their colleagues from the University of Würzburg, physicists from the group of Professor Alexander Szameit at the University of Rostock have devised a “funnel” for photons. Their discovery was recently published in the renowned journal Science and holds great promise for novel ultra-sensitive detectors as well as innovative applications in telecommunications and information processing.

The quantum-optical properties of light and its interaction with matter has fascinated the Rostock professor Alexander Szameit since College.

Im Focus: Stem Cells and Nerves Interact in Tissue Regeneration and Cancer Progression

Researchers at the University of Zurich show that different stem cell populations are innervated in distinct ways. Innervation may therefore be crucial for proper tissue regeneration. They also demonstrate that cancer stem cells likewise establish contacts with nerves. Targeting tumour innervation could thus lead to new cancer therapies.

Stem cells can generate a variety of specific tissues and are increasingly used for clinical applications such as the replacement of bone or cartilage....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

13th AKL – International Laser Technology Congress: May 4–6, 2022 in Aachen – Laser Technology Live already this year!

02.04.2020 | Event News

“4th Hybrid Materials and Structures 2020” takes place over the internet

26.03.2020 | Event News

Most significant international Learning Analytics conference will take place – fully online

23.03.2020 | Event News

 
Latest News

Graphene-based actuator swarm enables programmable deformation

02.04.2020 | Materials Sciences

Blocking the iron transport could stop tuberculosis

02.04.2020 | Life Sciences

EU project GALACTIC develops supply chain for Alexandrite laser crystals

02.04.2020 | Machine Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>