Mechanism explains complications associated with diabetes

Jun 23, 2010

New research uncovers a molecular mechanism that links diabetes with an increased risk of cardiovascular problems and sudden cardiac death. The study, published by Cell Press in the June 24 issue of the journal Neuron, finds that high blood sugar prevents vital communication between the brain and the autonomic nervous system, which controls many involuntary activities in the body.

"Diseases, such as diabetes, that disturb the function of the cause a wide range of abnormalities that include poor control of blood pressure, cardiac arrhythmias, and digestive problems," explains senior study author Dr. Ellis Cooper from McGill University in Montreal. "In most people with diabetes, the malfunction of the autonomic nervous system adversely affects their quality of life and shortens life expectancy."

To investigate why the autonomic nervous system malfunctions in diabetics, Dr. Cooper and colleagues examined the transmission of electrical signals from the brain to autonomic neurons. The brain communicates with autonomic neurons at synapses, a small gap between two where electrical signals from one nerve cell are sent to the next by chemical neurotransmitters. "In healthy individuals, synaptic transmission in the autonomic nervous system is strong and stable; however, if synapses on these neurons malfunction due to some disease process, the link between the nervous system and the periphery becomes disrupted," says Dr. Cooper.

Using a mouse model of diabetes, the researchers discovered that elevates reactive oxygen species in autonomic neurons and causes a disruption in synaptic transmission between the brain and the autonomic neurons. The researchers went on to show that this elevation in reactive oxygen species inactivates the neurotransmitter receptors at these synapses causing synaptic transmission to fail.

"Our work provides a new explanation for diabetic-induced disruptions of the autonomic ," concludes Dr. Cooper. "We show that an early step leading to autonomic abnormalities in diabetes is a depression in synaptic transmission triggered by events downstream of high blood sugar and reactive oxygen species. This synaptic depression is apparent as early as 1 week after the onset of diabetes and becomes more severe over time."

Explore further: Imaging study reveals white-matter deficits in users of codeine-containing cough syrups

More information: Campanucci et al.: “Report: Diabetes Depresses Synaptic Transmission in Sympathetic Ganglia by Inactivating nAChRs through a Conserved Intracellular Cysteine Residue.” Publishing in Neuron 66, 827-834, June 24, 2010. DOI:10.1016/j.neuron.2010.06.010

add to favorites email to friend print save as pdf

Related Stories

The APCs of nerve cell function

Jun 16, 2008

Rapid information processing in the nervous system requires synapses, specialized contact sites between nerve cells and their targets. One particular synapse type, cholinergic, uses the chemical transmitter acetylcholine ...

Premenstrual symptoms getting on your nerves?

Dec 20, 2007

For some women premenstrual syndrome (PMS) is a minor monthly annoyance, but for others, more severe symptoms seriously disrupt their lives. However despite the number of women affected, science has yet to offer a full explanation ...

UU Research Pushing Back the Frontiers of Space

Dec 04, 2004

Cutting edge research at the University of Ulster into how to make complex computers and communications systems manage themselves could power the next generation of US space probes, it was revealed today. Roy Sterritt, fro ...

Zinc plays important role in brain circuitry

Nov 22, 2006

To the multitude of substances that regulate neuronal signaling in the brain and spinal cord add a new key player: zinc. By engineering a mouse with a mutation affecting a neuronal zinc target, researchers have demonstrated ...

Recommended for you

Common infections tied to some stroke risk in kids

12 hours ago

A new study suggests that colds and other minor infections may temporarily increase stroke risk in children. The study found that the risk of stroke was increased only within a three-day period between a ...

Celebrities in 'Ice Bucket Challenge' to fight disease

23 hours ago

Steven Spielberg, Justin Bieber and Bill Gates are among many celebrities pouring buckets of ice water over their heads and donating to fight Lou Gehrig's disease, in a fundraising effort that has gone viral.

Study helps explain why elderly have trouble sleeping

Aug 20, 2014

As people grow older, they often have difficulty falling asleep and staying asleep, and tend to awaken too early in the morning. In individuals with Alzheimer's disease, this common and troubling symptom ...

Targeted brain training may help you multitask better

Aug 20, 2014

The area of the brain involved in multitasking and ways to train it have been identified by a research team at the IUGM Institut universitaire de gériatrie de Montréal and the University of Montreal.

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

lisasusan23
not rated yet Jun 24, 2010

Major brands always give out their popular brand samples (in a way it is similar to coupons) I alway use qualityhealth to get mine http://bit.ly/bhZA0u enjoy your free samples