A British-led study has determined glucose plays a key role in enabling cells that produce insulin to develop in an embryo’s pancreas.
That discovery, said Imperial College London researchers, could lead to development of new therapies for diabetes — a condition caused by insufficient levels of insulin.
Glucose prompts a gene called Neurogenin3 to switch on another gene, known as NeuroD, which is crucial for the normal development of beta cells. If glucose levels are low that gene is not switched on.
Insulin is the principal hormone that regulates the uptake of glucose and if the beta cells are unable to produce sufficient insulin, diabetes can develop.
The British researchers, in collaboration with scientists at Necker Hospital in Paris, hope understanding how to switch on NeuroD might eventually enable researchers to create such cells from stem cells. They could then transplant beta cells into patients with type 1 diabetes.
The study appears in the current issue of the Journal of Biological Chemistry.
Scientists have discovered three unsuspected regions of human DNA that contain clear genetic risk factors for type 2 diabetes, and another that is associated with elevated blood triglycerides.
The findings stem from the work of the Diabetes Genetics Initiative (DGI), a public-private partnership between the Broad Institute of MIT and Harvard, Novartis and Lund University, and they also reflect a close partnership with two other di?betes research groups.
The three groups’ studies, which appeared together in a recent advance online edition of Science, are among the first to apply a suite of genomic resources to clinical research. These genomic resources include the Human Genome Project, the SNP and HapMap Projects, and genome-scale laboratory and analytical tools.
“For the first time, it is possible to look across the human genome and discover new clues about the root causes of common, devastating diseases that arise from a combination of genes, environment and behavior,” said senior author David Altshuler, a principal investigator of DGI, director of the Broad Institute’s program in medical and population genetics and a professor at Massachusetts General Hospital and Harvard Medical School.
“The confirmed genetic contributors we and our collaborators have found open surprising new avenues for disease research, treatment and prevention,” he said.
With the aging of the population and the frequent excesses of modern lifestyles, type 2 diabetes and cardiac risk factors constitute a looming threat to human health, particularly in industrialized nations. Solutions to this burgeoning problem must include new, more effective treatments and the ability to identify “at risk” individuals–each of which requires innovative directions for future research.
The DGI study is one of the first large-scale studies of human genetic variability, aiming to reveal genetic connections to type 2 diabetes and other cardiovascular risk factors such as blood insulin levels, cholesterol levels, blood pressure and body weight. Each of these traits is considered “complex” because it involves a mix of inherited, environmental and behavioral factors.
The scientists’ approach, known as a “genome-wide association study,” involves scanning thousands of individuals’ genomes for single letter changes, called single nucleotide polymorphisms (SNPs). Due to the block-like nature of the human genome, certain SNPs can serve as signposts, highlighting pieces of nearby DNA that may play a causal role in disease.
Using this approach, the DGI team and their collaborators identified and confirmed three novel regions of the genome that influence the risk of type 2 diabetes, as well as a genomic region that is linked with blood triglyceride levels. Perhaps the most intriguing result involves a DNA region that lies far from any known annotated genes. Such genomic “outsiders” would have been incredibly difficult to find by traditional hypothesis-driven approaches.
The other regions linked to diabetes lie near genes with known biochemical functions, but ones never before connected to the disease. Interestingly, the region implicated in triglyceride levels involves a gene that has long been known to play a role in modulating blood glucose.
Based on initial results, the DGI scientists turned to replicating the most promising findings in independent samples–a critical aspect of the genomic method. The scientists worked together with two other groups that performed similar genomic analyses of type 2 diabetes: the Wellcome Trust Case Control Consortium/UK Type 2 Diabetes Genetics Consortium (WTCCC/UKT2D) and the Finland-United States Investigation of NIDDM (non-insulin-dependent diabetes mellitus) Genetics (FUSION).
By virtue of their close collaboration, DGI, WTCCC/UKT2D and FUSION researchers identified at least eight clear genetic risk factors for type 2 diabetes, including three that had never before been found, as well as several other probable risk factors that warrant further study.
Source: MIT
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A diet rich in fiber from cereals and in magnesium may help lower the risk of developing type 2 diabetes, German researchers report.
Ann Albright, president-elect for health care and education at the American Diabetes Association, said the suggestion that fiber from cereal might be better than fiber from fruits and vegetables in preventing type 2 diabetes “warrants further investigation. But I don’t think we should take away the idea that fruits and vegetables are not important,” she added.
As for the nutrient magnesium, “there are a whole lot of challenges around the study of micronutrients,” Albright said. “They are difficult to study. I don’t think the public health message is that we should go out and up our intake of magnesium.”
The mechanism by which magnesium intake might affect the risk of diabetes “is unclear,” she said.
Type 2 diabetes, which generally occurs in the adult years as the body loses it ability to metabolize sugar adequately, is a growing problem, due largely to growing obesity rates, the German researchers noted. Estimates suggest that the ?umber of people worldwide with type 2 diabetes may rise from 171 million in 2000 to 370 million by 2030, according to background information in the article. The associated illnesses, death and health-care costs linked to the disease underscore the need for effective preventive measures, the study authors noted.
For the study, conducted by researchers at the German Institute of Human Nutrition Potsdam-Rehbruecke, more than 9,700 men and 15,365 women, 35 to 65 years old, who completed a food questionnaire were then followed for an average of seven years.
The researchers also did a meta-analysis — or review — of previous studies about the relationship between fiber or magnesium intake and risk of diabetes.
Dividing people in the study into five groups based on their intake of fiber from cereals, the researchers found that those who ate the most had a 27 percent lower risk of developing type 2 diabetes than those who ate the least. Greater fiber intake from fruits and vegetables was not associated with diabetes risk, the study found.
Participants who consumed the most magnesium had a 23 percent lower risk of developing type 2 diabetes than those who consumed the least. Green vegetables such as spinach are good sources of magnesium, as are nuts like almonds and cashews.
The research did not touch directly on one important lifestyle issue, physical activity, Albright said. Many other studies have shown “strong evidence of physical activity, as it relates to weight loss, in preventing or delaying development of diabetes,” she said.
“So, the take-home messages are that people do need to keep their weight in a healthy range,” she said. “And fiber intake is a major component of a healthy diet.”
The source of the fiber — fruits, vegetables or cereals — does not seem to be of major importance, Albright said. “Unfortunately, many people do not get a lot of fiber in their diet,” she said.
And many people do not get enough physical activity — 30 minutes a day, most days of the week, is recommended, Albright said.
The findings were published in the May 14 issue of Archives of Internal Medicine.
Members of Congress plotted a campaign against diabetes yesterday, introducing legislation that would allot $120 million to research and projects in the upcoming year to discover possible ways to prevent the spread of the disease and its complications.
“We know that diabetes can either be prevented or effectively managed through proper diet and exercise in many cases,” said Rep. Vito Fossella (R-Staten Island/Brooklyn), who co-sponsored the legislation along with Sens. Hillary Clinton (D-New York) and Susan Collins (R-Maine), and Rep. Eliot Engel (D-New York).
Diabetes is a disease marked by the body’s inability to digest glucose. The rate of Type 2 diabetes — which is believed to be caused by a genetic predisposition for the disease mixed with obesity, lack of exercise and other lifestyle choices — has dramatically spiked throughout the nation.
An estimated 60 million or more Americans are living with diabetes or at risk of developing the disease. On Staten Island, an estimated 12.5 percent of all residents have the disease, according to a recent city Health Department study.
Currently, money flows more easily toward treating complications from diabetes — such as amputations and dialysis — than it does toward weight-loss, nutrition education and other preventive and maintenance programs, Sen. Clinton said.
The legislation proposed yesterday would provide $90 million to the Centers for Disease Control and Prevention’s Division of Diabetes Translation for diabetes su?veillance, research and educational activities. It would also allot $30 million for three four-year projects that would examine how best to translate diet and exercise interventions into effective clinical practice.
“Diabetes and obesity prevalence are increasing at alarming rates,” said Dr. Thomas Frieden, the city’s health commissioner. “It is essential that the federal government begin to give a higher priority to prevention and lifestyle modification programs.”
Diabetes appears to harm sperm and may decrease a man’s fertility, says a British study in the journal Human Reproduction.
Many men having diabetes for a long period of time are sufferuring from Erectile Dysfunction which is commonly known as ED. Cialis, Viagra, and Levitra (vardenafil) are 3 major FDA approved medications that treats ED.
Researchers analysed sperm samples from 56 men and found that 52 percent of men with diabetes had fragmented sperm DNA, compared with 32 percent of men without the disease, BBC News reported.
The diabetic men also had higher rates of DNA deletions in the mitochondria, which produce energy for cells. Defective sperm DNA can cause male infertility, pregnancy failure and miscarriage, BBC News reported.
The study also found that the diabetic men had significantly lower-than-normal semen volume, but showed no differences in sperm concentration, structure or movement.
While it’s not clear whether diabetes actually affects male fertility, the researchers said their findings are troubling given rapidly rising rates of diabetes. They recommended further research, BBC News reported.
A study by a researcher at the University of Wisconsin (UW) has discovered that topical honey can heal diabetes sores completely.
Jennifer Eddy of UW Health’s Eau Claire Family Medicine Clinic, who treated her borderline diabetic patient Catrina Hurlburt with honey therapy, said that Hurlburt’s case is a good example of the ‘potential health care savings’.
“Unsuccessful conventional care for ulcers can cost thousands of dollars. Therapy with honey may only cost a few hundred,” Eddy said.
Experts believe that treating wounds with honey has tremendous potential for the approximately 200 million people in the world with diabetes, 15 percent of whom will develop an ulcer, usually because of impaired sensation in their feet.
Diabetics typically have poor circulation and decreased ability to fight infection. Diabetic ulcers treated with long courses of systemic antibiotics can become colonized with drug-resistant organisms- so-called “superbugs” such as Methicillin-resistant Staphylococcus aureus (MRSA).
Since honey fights bacteria in numerous ways, it is essentially immune to resistance. Honey’s acidic pH, low water content (which effectively dehydrates bacteria), and the hydrogen peroxide secreted by its naturally-occurring enzymes make it ideal for combating organisms that have developed resistance to standard antibiotics.
“This is a tremendously important issue for public health,” explained Eddy, adding that the Centers for Disease Control and the World Health Organization have identified bacterial resistance as one of the most important medical problems of our day.
Patients in the clinical trial will receive ulcer care and treatment by an expert podiatrist. Half will be randomly assigned to receive honey, while the other half will receive a wound-care gel that has been compounded with inert components to give it the flavor and color of honey. The ulcers will be measured to see how quickly they heal, to evaluate whether honey or the standard wound gel is better for healing.
If honey proves the more effective method, Eddy cautions patients against using it at home without a physician’s involvement.
“Unfortunately, diabetic ulcers are very complicated, and honey would only be part of the solution,” she says. Successful care also requires off-loading-avoiding walking and putting weight on the sore-and the sterile removal of dead skin and bacteria from the wound.”If we can prove that honey promotes healing in diabetic ulcers, we can offer new hope for many patients,” said Eddy.
“Not to mention the cost benefit, and the issue of bacterial resistance. The possibilities are tremendous,” added Eddy.
An herb long-used in traditional Indian medicine may help people with type 2 diabetes control their blood sugar, a new study suggests.
Researchers found that the herb, called Salacia oblonga, reduced post-meal blood sugar surges in 66 men and women with type 2 diabetes.
Also known as Saptrangi and Ponkoranti, S. oblonga is from a native shrub plant found in the forests of India and Sri Lanka. The roots and stems of the herb are used in Ayurvedic and traditional Indian medicine to treat obesity and diabetes.
The findings, reported in the American Journal of Clinical Nutrition, support the results of earlier work that looked at S. oblonga’s blood sugar effects in people without diabetes. And the result suggest that the herb could be used along with diet, exercise and medication to help manage type 2 diabetes, according to the study authors.
The researchers, led by Jennifer A. Williams, are with Columbus, Ohio-based Abbott Laboratories, which has funded previous research on the herb.
For the study, Williams and her colleagues asked participants to drink a high-carbohydrate liquid meal replacement on three separate occasions. On one day they had the meal alone and on another two days they consumed the drink along with a dose of S. oblonga extract, either 240 mg or 480 mg.
On average, the study found, the lower S. oblonga dose decreased participants’ peak blood sugar response by 19 percent, while the higher dose lowered it by 27 percent. Both doses also tempered the normal post-meal increase in insulin, a hormone that regulates blood sugar.
The S. oblonga plant grows in limited areas of Asia and is not widely known in the U.S. Extracts are used in Japan, however, as an ingredient in foods and supplements intended to manage diabetes and obesity.
The herb is thought to work similarly to oral diabetes drugs called alpha-glucosidase inhibitors, which impede the body’s absorption of carbohydrates.
S. oblonga, and other substances like it, could be “ideal” nutritional therapies for diabetes, Williams and her colleagues write. People often find it tough to stick with diet restrictions, the researchers note, and a supplement like S. oblonga could allow diabetics to eat a carbohydrate-rich meal without an overly high blood sugar response.
Studies should now look at the herb’s effects on blood sugar control over the long-ter?, the researchers conclude.
SOURCE: American Journal of Clinical Nutrition, July 2007.