Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New tactic for controlling blood sugar in diabetes contradicts current view of the disease

05.09.2011
Study finds inflammation may be part of the solution, not the problem

Increased low-grade inflammation in the body resulting from obesity is widely viewed as contributing to type 2 diabetes. Going against this long-held belief, researchers from Children's Hospital Boston report that two proteins activated by inflammation are actually crucial for maintaining good blood sugar levels – and that boosting the activity of these proteins can normalize blood sugar in severely obese and diabetic mice.

The research, led by Umut Ozcan, MD, in the Division of Endocrinology at Children's, is reported in the October issue of Nature Medicine, published online September 4.

"This finding is completely contrary to the general dogma in the diabetes field that low-grade inflammation in obesity causes insulin resistance and type 2 diabetes," says Ozcan. "For 20 years, this inflammation has been seen as detrimental, whereas it is actually beneficial."

Ozcan's team previously showed that obesity places stress on the endoplasmic reticulum (ER), a structure in the cell where proteins are assembled, folded and dispatched to do jobs for the cell. This so-called "ER stress" impairs the body's response to insulin in maintaining appropriate blood glucose levels, and is a key link between obesity and type 2 diabetes. Last year, Ozcan and colleagues showed that a protein that relieves ER stress, called XBP1s, cannot function in obese mice. Earlier this year, they showed that activating XBP1s artificially in the liver normalized high blood sugar in obese, insulin-resistant type 2 diabetic mice (as well as lean, insulin-deficient type 1 diabetic mice).

The new study shows that a second protein triggered by inflammatory signals, p38 MAPK, chemically alters XBP1s, enhancing its activity -- and that without these alterations, XBP1s cannot function to maintain normal glucose levels. The study further showed that obese mice have reduced p38 MAPK activity, and that re-activating p38 MAPK in the liver reduced their ER stress, increased insulin sensitivity and glucose tolerance, and significantly reduced blood glucose levels.

Together, the findings suggest that either increasing p38 MAPK activity -- despite its being an inflammatory signal -- or increasing XBP-1 activity by other means could represent new therapeutic options for diabetes.

The study also suggests a new model for understanding type 2 diabetes, in which obesity may interfere with the ability of people's cells to respond to inflammatory signals. "It may be that inflammatory pathways are not working optimally and there could be a resistance to cytokines which mediates the inflammation," Ozcan says. "This could be a paradigm shift for the field."

The researchers also raise a possible down side in using p38 MAPK inhibitors to treat inflammatory diseases such as Crohn's disease, psoriasis and asthma. "These therapeutic approaches should … be evaluated within the context of our results, and in light of the possibility that inhibition of XBP1s activity also decreases the ability of the cell to cope with the inflammatory conditions," they write.

The study (doi:10.1038/nm.2449) was supported by the National Institutes of Health and the Timothy Murphy funds provided to the Division of Endocrinology, Children's Hospital Boston. Jaemin Lee, PhD, and Cheng Sun, PhD, were co-first authors on the paper.

Children's Hospital Boston is home to the world's largest research enterprise based at a pediatric medical center, where its discoveries have benefited both children and adults since 1869. More than 1,100 scientists, including nine members of the National Academy of Sciences, 11 members of the Institute of Medicine and nine members of the Howard Hughes Medical Institute comprise Children's research community. Founded as a 20-bed hospital for children, Children's Hospital Boston today is a 396 bed comprehensive center for pediatric and adolescent health care grounded in the values of excellence in patient care and sensitivity to the complex needs and diversity of children and families. Children's also is the primary pediatric teaching affiliate of Harvard Medical School. For more information about research and clinical innovation at Children's, visit: http://vectorblog.org.

Children's Hospital Boston | EurekAlert!
Further information:
http://vectorblog.org

More articles from Health and Medicine:

nachricht Investigators may unlock mystery of how staph cells dodge the body's immune system
22.09.2017 | Cedars-Sinai Medical Center

nachricht Monitoring the heart's mitochondria to predict cardiac arrest?
21.09.2017 | Boston Children's Hospital

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Rainbow colors reveal cell history: Uncovering β-cell heterogeneity

22.09.2017 | Life Sciences

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>