PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Loss of function of a single gene linked to diabetes in mice

Gene defect prevents insulin from ever reaching bloodstream

2014-01-04
(Press-News.org) Contact information: Sharon Parmet
sparmet@uic.edu
312-413-2695
University of Illinois at Chicago
Loss of function of a single gene linked to diabetes in mice Gene defect prevents insulin from ever reaching bloodstream

Researchers from the University of Illinois at Chicago College of Medicine have found that dysfunction in a single gene in mice causes fasting hyperglycemia, one of the major symptoms of type 2 diabetes. Their findings were reported online in the journal Diabetes.

If a gene called MADD is not functioning properly, insulin is not released into the bloodstream to regulate blood sugar levels, says Bellur S. Prabhakar, professor and head of microbiology and immunology at UIC and lead author of the paper.

Type 2 diabetes affects roughly 8 percent of Americans and more than 366 million people worldwide. It can cause serious complications, including cardiovascular disease, kidney failure, loss of limbs and blindness.

In a healthy person, beta cells in the pancreas secrete the hormone insulin in response to increases in blood glucose after eating. Insulin allows glucose to enter cells where it can be used as energy, keeping glucose levels in the blood within a narrow range. People with type 2 diabetes don't produce enough insulin or are resistant to its effects. They must closely monitor their blood glucose throughout the day and, when medication fails, inject insulin.

In previous work, Prabhakar isolated several genes from human beta cells, including MADD, which is also involved in certain cancers. Small genetic variations found among thousands of human subjects revealed that a mutation in MADD was strongly associated with type 2 diabetes in Europeans and Han Chinese.

People with this mutation had high blood glucose and problems of insulin secretion – the "hallmarks of type 2 diabetes," Prabhakar said. But it was unclear how the mutation was causing the symptoms, or whether it caused them on its own or in concert with other genes associated with type 2 diabetes.

To study the role of MADD in diabetes, Prabhakar and his colleagues developed a mouse model in which the MADD gene was deleted from the insulin-producing beta cells. All such mice had elevated blood glucose levels, which the researchers found was due to insufficient release of insulin.

"We didn't see any insulin resistance in their cells, but it was clear that the beta cells were not functioning properly," Prabhakar said. Examination of the beta cells revealed that they were packed with insulin. "The cells were producing plenty of insulin, they just weren't secreting it," he said.

The finding shows that type 2 diabetes can be directly caused by the loss of a properly functioning MADD gene alone, Prabhakar said. "Without the gene, insulin can't leave the beta cells, and blood glucose levels are chronically high."

Prabhakar now hopes to investigate the effect of a drug that allows for the secretion of insulin in MADD-deficient beta cells.

"If this drug works to reverse the deficits associated with a defective MADD gene in the beta cells of our model mice, it may have potential for treating people with this mutation who have an insulin-secretion defect and/or type 2 diabetes," he said.



INFORMATION:

Jose Oberholzer, chief of transplantation surgery, and Ajay V. Maker, assistant professor of surgery at the University of Illinois Hospital & Health Sciences System; Yong Wang, Ryan Carr, Samir Haddad, Ze Li, Lixia Qian, and Qian Wang of the UIC College of Medicine; and Liang-Cheng Li of Xiamen University are co-authors on the paper.

This research was supported by grant R01DK91526 from the National Institutes of Health.



ELSE PRESS RELEASES FROM THIS DATE:

Severe mental illness tied to higher rates of substance use

2014-01-04
Severe mental illness tied to higher rates of substance use New NIH study shows that certain protective factors do not exist in those with severe mental illness People with severe mental illness such as schizophrenia or bipolar disorder have a higher ...

UC research uncovers how ancient artists used palace floor as a creative canvas

2014-01-03
UC research uncovers how ancient artists used palace floor as a creative canvas The floors of Greek Bronze Age palaces were made of plaster that was often incised and painted with grids containing brightly colored patterns and/or marine animal figures. In researching ...

Amber fossil reveals ancient reproduction in flowering plants

2014-01-03
Amber fossil reveals ancient reproduction in flowering plants CORVALLIS, Ore. – A 100-million-year old piece of amber has been discovered which reveals the oldest evidence of sexual reproduction in a flowering plant – a cluster of 18 tiny flowers ...

ADC evaluation for the changes of infarction core and remote regions after MCAO

2014-01-03
ADC evaluation for the changes of infarction core and remote regions after MCAO Supratentorial cerebral infarction can cause functional inhibition of remote regions such as the cerebellum, which may be relevant to diaschisis. This phenomenon is often analyzed ...

ClC-3 chloride channel in hippocampal neuronal apoptosis

2014-01-03
ClC-3 chloride channel in hippocampal neuronal apoptosis Over-production of nitric oxide and ion disturbance are involved in neuronal apoptosis around the ischemic area following ischemic brain injury. Prof. Quanzhong Chang and team from Zhuhai Campus of Zunyi ...

Role of endoplasmic reticulum stress in the loss of RGCs in diabetic retinopathy

2014-01-03
Role of endoplasmic reticulum stress in the loss of RGCs in diabetic retinopathy Endoplasmic reticulum stress is closely involved in the early stage of diabetic retinopathy. According a study published in the Neural Regeneration Research (Vol. 8, No. 33, 2013), ...

Novel exfoliation method developed by NUS chemists paves the way for 2-dimensional materials to be used in printable photonics and electronics

2014-01-03
Novel exfoliation method developed by NUS chemists paves the way for 2-dimensional materials to be used in printable photonics and electronics Versatility of new technique shows promise as new benchmark in exfoliation chemistry of 2-dimensional chalcogenides Singapore, ...

Fear of childbirth predicts postpartum depression

2014-01-03
Fear of childbirth predicts postpartum depression Expectant women with prenatally diagnosed fear of childbirth are at an increased risk of postpartum depression, according to a study of over 500,000 mothers in Finland. Women with a ...

25 years of DNA on the computer

2014-01-03
25 years of DNA on the computer A review of the computer simulations of nuclear DNA DNA carries out its activities "diluted" in the cell nucleus. In this state it synthesises proteins and, even though it looks like ...

Higher vitamin D levels in pregnancy could help babies become stronger

2014-01-03
Higher vitamin D levels in pregnancy could help babies become stronger Children are likely to have stronger muscles if their mothers had a higher level of vitamin D in their body during pregnancy, according to new research from the Medical Research Council ...

LAST 30 PRESS RELEASES:

Corpse flowers are threatened by spotty recordkeeping

Riding the AI wave toward rapid, precise ocean simulations

Are lifetimes of big appliances really shrinking?

Pink skies

Monkeys are world’s best yodellers - new research

Key differences between visual- and memory-led Alzheimer’s discovered

% weight loss targets in obesity management – is this the wrong objective?

An app can change how you see yourself at work

NYC speed cameras take six months to change driver behavior, effects vary by neighborhood, new study reveals

New research shows that propaganda is on the rise in China

Even the richest Americans face shorter lifespans than their European counterparts, study finds

Novel genes linked to rare childhood diarrhea

New computer model reveals how Bronze Age Scandinavians could have crossed the sea

Novel point-of-care technology delivers accurate HIV results in minutes

Researchers reveal key brain differences to explain why Ritalin helps improve focus in some more than others

Study finds nearly five-fold increase in hospitalizations for common cause of stroke

Study reveals how alcohol abuse damages cognition

Medicinal cannabis is linked to long-term benefits in health-related quality of life

Microplastics detected in cat placentas and fetuses during early pregnancy

Ancient amphibians as big as alligators died in mass mortality event in Triassic Wyoming

Scientists uncover the first clear evidence of air sacs in the fossilized bones of alvarezsaurian dinosaurs: the "hollow bones" which help modern day birds to fly

Alcohol makes male flies sexy

TB patients globally often incur "catastrophic costs" of up to $11,329 USD, despite many countries offering free treatment, with predominant drivers of cost being hospitalization and loss of income

Study links teen girls’ screen time to sleep disruptions and depression

Scientists unveil starfish-inspired wearable tech for heart monitoring

Footprints reveal prehistoric Scottish lagoons were stomping grounds for giant Jurassic dinosaurs

AI effectively predicts dementia risk in American Indian/Alaska Native elders

First guideline on newborn screening for cystic fibrosis calls for changes in practice to improve outcomes

Existing international law can help secure peace and security in outer space, study shows

Pinning down the process of West Nile virus transmission

[Press-News.org] Loss of function of a single gene linked to diabetes in mice
Gene defect prevents insulin from ever reaching bloodstream