Navigation Links
Micro-RNA blocks the effect of insulin in obesity
Date:3/31/2011

This release is available in German.

Body weight influences the risk of developing diabetes: between 80 and 90 percent of patients with type 2 diabetes are overweight or obese. According to scientists at the Max Planck Institute for Neurological Research in Cologne and the Cologne Cluster of Excellence in Cellular Stress Responses in Aging-associated Diseases (CECAD), short ribonucleic acid molecules, known as micro-RNAs, appear to play an important role in this mechanism. The researchers discovered that the obese mice form increased levels of the regulatory RNA molecule miRNA-143. miRNA-143 inhibits the insulin-stimulated activation of the enzyme AKT. Without active AKT, insulin cannot unfold its blood-sugar-reducing effect and the blood sugar level is thrown out of kilter. This newly discovered mechanism could provide the starting point for the development of new drugs for the treatment of diabetes.

The hormone insulin plays a key role in the regulation of blood sugar levels. If there is too much glucose in the blood, insulin opens the glucose transport channels in the cell membrane of muscles and fat cells. Glucose then reaches the body's cells and the blood's sugar content sinks. Additionally, the insulin inhibits the production of new sugar in the liver. Type 2 diabetics are able to produce sufficient volumes of insulin; however, their cells are resistant to it - and the hormone is unable to fulfil its task. If untreated, this disease damages the blood vessels due to the raised blood sugar levels, which can lead to a heart attack or stroke.

The molecular processes in the body's cells responsible for the connection between body weight and diabetes are largely unknown. However, in all tissues that respond to insulin, Micro-RNAs can be found. The Cologne-based scientists working with Jens Brning, Director at the Max Planck Institute for Neurological Research and scientific coordinator of the Cologne Cluster of Excellence in Cellular Stress Responses in Aging-associated Diseases at the University of Cologne assume, therefore, that micro-RNAs may also play a role in type 2 diabetes. These short ribonucleic acid molecules can regulate the activity of genes and thus control protein production.

The research group in Cologne has now discovered a new mechanism that leads to insulin resistance of the cells. Accordingly, obese mice form excess miRNA-143 in their livers. This RNA molecule silences genes that are responsible for the activation of the enzyme AKT and therefore inhibits insulin from activating AKT. "AKT is important for glucose transport in the cell and for the inhibition of glucose synthesis in the liver. When the enzyme is inhibited, insulin fails to take effect and the blood sugar remains elevated," explains Jens Brning.

For their research study, the researchers compared normal weight mice with obese mice with type 2 diabetes. They discovered that the diseased animals produce more than twice as much miRNA-143 in their livers than the normal ones. Moreover, the researchers found only a low concentration of the protein ORP8 in the obese mice which formed large quantities of miRNA-143. ORP8 stimulates insulin to activate AKT and therefore reduces the sugar content of the blood. If ORP8 is lacking, insulin is unable to take effect and the AKT remains inactive.

The researchers do not yet know why obese mice form more miRNA-143 than their normal weight counterparts. "If we succeed in explaining the signalling paths in the cell that lead to the production of miRNA-143, we will have a starting point for the development of new drugs for the treatment of type 2 diabetes," explains Jens Brning in reference to future research plans.


'/>"/>

Contact: Dr. Cornelia Weigelt
weigelt@nf.mpg.de
49-221-472-6301
Max-Planck-Gesellschaft
Source:Eurekalert

Related biology news :

1. New evidence in plants shows micro-RNA can move
2. Morphine blocks tumor growth
3. New arsenic nanoparticle blocks aggressive breast cancer
4. Study shows adding UV light helps form Missing G of RNA building blocks
5. Applied physicists create building blocks for a new class of optical circuits
6. Supplement blocks the initiation of breast cell mutations by estrogens
7. Natural compound blocks hepatitis C infection
8. Vaccine blocks malaria transmission in lab experiments
9. Natural brain substance blocks weight gain in mice, UT Southwestern researchers discover
10. New study shows you can have your candy and eat it too -- without adverse health effects
11. Satellites show effect of 2010 drought on Amazon forests
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:12/15/2016)... Calif. , Dec. 15, 2016   WaferGen ... publicly held genomics technology company, announced today that on ... Listing Qualifications Department of The Nasdaq Stock Market LLC ... closing bid price of WaferGen,s common stock had been ... Accordingly, WaferGen has regained compliance with Listing Rule 5550(a)(2) ...
(Date:12/15/2016)... 2016  There is much more to innovative access ... engine. Continental will demonstrate the intelligence of today,s solutions ... . Through the combination of the keyless entry and ... elements, the international technology company is opening up new ... "The integration of biometric elements brings our ...
(Date:12/8/2016)... 2016 Market Research Future published a half cooked research ... Biometric Security and Service Market is expected to grow over the ... Market Highlights: ... Mobile Biometric Security and Service Market ... need of authentication and security from unwanted cyber threats. The increasing ...
Breaking Biology News(10 mins):
(Date:1/16/2017)... Jan. 16, 2017   Valentin A. Pavlov, PhD ... , president and CEO of The Feinstein Institute ... analysis of how the nervous system regulates the immune ... bioelectronic medicine devices to treat disease and ... Neuroscience . The paper examines various studies ...
(Date:1/16/2017)... , Jan. 16, 2017  Eurofins Genomics today ... will allow more customers to receive their primers in ... or compromise in quality found with other providers. Express ... United States at no additional fee. ... routine genetic studies, including DNA sequencing, genotyping, site-directed mutagenesis, ...
(Date:1/14/2017)... 13, 2017  The Alliance for Safe Biologic Medicines ... FDA final guidance on biologic naming: ... in emphasizing the importance of distinct naming for all ... the benefits biosimilars will bring to patients, including new ... the portion of the Guidance dealing with suffix design ...
(Date:1/13/2017)... and Markets has announced the addition of the "Global Biopolymers Market ... ... 16.83% during the period 2017-2021. The report covers the ... 2017-2021. To calculate the market size, the report considers the revenue generated ... a a discussion of the key vendors operating in this market. ...
Breaking Biology Technology: