In diabetes, patients suffer a higher risk of chronic bacterial and fungal infections but until now little has been known about the mechanisms involved. Now new research led by Dr Daniel Mitchell at the University of Warwick's Warwick Medical School has found a novel relationship between high glucose and the immune system in humans.
The researchers have found that specialized receptors that recognize molecules associated with bacteria and fungi become "blind" when glucose levels rise above healthy levels. The new research may also help explain why diabetic complications can also include increased risk of viral infections such as influenza, and also inflammatory conditions such as cardiovascular disease.
The researchers looked at the similarities in chemical structure between glucose in blood and body fluids, and two other sugar called mannose and fucose. These sugars are found on the surfaces of bacteria and fungi and act as targets for receptors in our body that have evolved to detect and bind to microbial sugars to then combat the infection.
The research found that high levels of glucose outcompetes the binding of mannose and fucose to the specialized immune receptors, potentially blocking these receptors from detecting infectious bacteria and fungi. Glucose also binds in such a way that it inhibits the chemical processes that would normally then follow to combat infections. If this happens it can inhibit a range of key processes including:
It can inhibit the function of immune system receptors called C-type lectins such as MBL (Mannose-binding lectin) which are known to bind to a sugar known as mannose that is present in the structure of infectious fungal bacterial cell walls. Unlike glucose, mannose does not exist in mammals as a free sugar in the blood.
The loss of MBL function may also predispose the body to chronic inflammatory diseases, since MBL is involved in the processing and clearance of apoptotic cells (dying cells).
A number of C-type lectins tat can be affected by raised glucose levels, including MBL, but also including immune cell surface receptors DC-SIGN and DC-SIGNR, are found in key parts of our circulation and vascular system such as plasma, monocytes, platelets and endothelial cells that line blood vessels. Inhibiting the function of these key molecules in those settings could contribute to diabetic cardiovascular and renal complications.
Warwick Medical School researcher Dr Daniel Mitchell said:
"Our findings offer a new perspective on how high glucose can potentially affect immunity and thus exert a negative impact on health. It also helps to emphasize the importance of good diet on preventing or controlling diseases such as diabetes. We will build on these ideas in order to consolidate the disease model and to investigate new routes to treatment and prevention."
Notes for editors:
1. The research will be published in the journal Immunobiology and is entitled "High glucose disrupts oligosaccharide recognition function via competitive inhibition: A potential mechanism for immune dysregulation in diabetes mellitus" .
2. The full list of authors is: Dr Daniel Mitchell, Dr Harpal S. Randeva, Rebecca Ilyas, Bee K. Tan, and Daniel Zehnder of the Clinical Sciences Research Institute, University of Warwick; Hendrik Lehnert of the University of Warwick and the First Medical Department, University of Lübeck, Germany; Russell Wallis of the Department of Infection and Immunity, University of Leicester; Elizabeth J. Soilleux of the Nufﬁeld Department of Clinical Laboratory Sciences, University of Oxford; Robert B. Sim of the MRC Immunochemistry Unit, University of Oxford, UK ; and Paul Townsend of the Infection, Inﬂammation and Immunology Division, University of Southampton.
3. The pre publication version of the paper is at http://www.ncbi.nlm.nih.gov/pubmed/20674073 And the doi is :10.1016/j.imbio.2010.06.002
For further information please contact:Dr Daniel Mitchell, Clinical Science Research Institute,
Kelly Parkes-Harrison | EurekAlert!
Researchers identify potentially druggable mutant p53 proteins that promote cancer growth
09.12.2016 | Cold Spring Harbor Laboratory
Plant-based substance boosts eyelash growth
09.12.2016 | Fraunhofer-Institut für Angewandte Polymerforschung IAP
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine