April 10, 2006, 7:13 PM CT

Obesity: Is It Genetic?

Do you have big hips or a "beer" belly? Are you "apple-shaped" or "pear-shaped"? It makes a difference, since we know that abdominal obesity is linked to diabetes and a number of other metabolic conditions, i.e., the metabolic syndrome. What's new is that, as per a new study led by scientists at Joslin Diabetes Center in Boston, both obesity and body shape seem to be controlled by important genes that are part of the mechanisms regulating normal development.

"By looking at your genes, we can tell how fat you are and how your body fat will be distributed," said lead researcher C. Ronald Kahn, M.D., President of Joslin and the Mary K. Iacocca Professor of Medicine at Harvard Medical School. In lower animals, he added, it's long been known that genes play an important role in the body's development. "Genes tell the body where the head goes and where the tail goes, what goes on the front and what goes on the back. In insects, genes determine if the wings go on the front or back and whether they will be large or small. So it's not surprising that in humans, genes may determine how a number of fat cells we have and where they are located," he said.

Together with Joslin post-doctoral fellow Stephane Gesta, Ph.D., and his colleagues at the University of Leipzig in Gera number of, the scientists for the first time used gene chips as a tool to understand what genes might control the development of fat inside the abdomen versus fat under the skin. The resulting study will be published online today, April 10, in the journal Proceedings of the National Academy of Sciences.........

Posted by: JoAnn      Permalink         Source

April 5, 2006, 11:48 PM CT

Effects Of Weight Loss In Adolescents

A team of scientists at Washington University School of Medicine in St. Louis is studying how fatty liver disease affects sugar and fat metabolism in overweight adolescents and how losing weight affects the condition. In the last 30 years, the number of overweight children has doubled in the United States, and overweight children are at increased risk for the problem.

In fatty liver disease, fat accumulates in liver cells. A patient is diagnosed with fatty liver when there is more than 5 percent fat in the liver. In children and adolescents, fatty liver is most common in those who are overweight, but it also can occur in young people with diabetes or, less commonly, with other conditions.

Those with fatty liver disease may have an enlarged liver or elevations in liver enzyme tests. Most do not have obvious symptoms, but some may complain of fatigue, malaise or vague abdominal pain that can bring them to the attention of a physician. If fatty liver goes untreated and risk factors are not controlled, a small percentage of young people may progress to liver scarring or even liver failure.

Fatty liver disease is thought to affect about 20 percent of the population in the developed world, but like type 2 diabetes, it has been uncommon in young people until recently.........

Posted by: JoAnn      Permalink         Source

March 13, 2006, 10:20 PM CT

Diabetic patients overestimate body weight

Heavier patients with diabetes are more likely to overestimate their "healthiest" body weight compared to those of normal weight, as per a research studyreported in the current issue of Diabetes Care.

"We wanted to understand how well patients with diabetes could identify healthy body weight because self-management is an essential part of diabetes therapy," said Kathleen McTigue, M.D., M.P.H., assistant professor of medicine at the University of Pittsburgh and first author of the study. "Understanding weight-related health risk could be an important step toward setting healthy lifestyle goals and effective weight management."

In a survey of 2,461 diabetes patients, responses revealed that a number of had a less-than-accurate view of healthy body weight.

"Among respondents, 41 percent reported a 'healthiest' weight for their height that actually measured in the overweight body mass index (BMI) range, and 6 percent reported a 'healthiest' weight that was obese," said Dr. McTigue, who also is an internal medicine specialist associated with the University of Pittsburgh Diabetes Institute (UPDI). "One participant selected a BMI in the underweight range as 'healthiest.' ".

Among respondents whose BMI measurements classified them as obese, 66 percent identified overweight or obese dimensions as ideal for health. Among the overweight, some 41 percent chose a higher-than-optimal body weight as healthy. In contrast, only 4 percent of normal-weight patients overestimated healthy body weight.........

Posted by: JoAnn      Permalink         Source

March 9, 2006, 11:06 PM CT

Mechanisms Behind Oral Diabetic Agents

Thiazolidinediones (TZD's) are drugs usually prescribed to patients with type 2 diabetes, the most common form of diabetes. Current U.S. Food and Drug Administration-approved agents are known as Actos (pioglitazone) and Avandia (rosiglitazone). These oral agents improve blood glucose levels in people with diabetes by improving insulin action in the body. While it is known that these drugs work primarily by binding to a receptor in the nucleus of cells called Peroxisome Proliferator Activated Receptor-gamma (PPARg), all of the molecular signaling events important for the drugs to work are not completely understood.

A new study by scientists at Joslin Diabetes Center in Boston helps to explain how these drugs work. The manuscript appears in the March edition of the American Diabetes Association's journal Diabetes.

In a clinical research study, Joslin scientists Allison B. Goldfine, M.D., Sarah Crunkhorn, Ph.D., and Mary-Elizabeth Patti, M.D., examined muscle and fat tissue from patients with type 2 diabetes before and after they took the drug rosiglitazone. The scientists found that levels of two proteins called Necdin and E2F4, which are important in regulating cell replication, are altered in muscle and fat after patients took the drug for two months. Dr. Goldfine is an Investigator in Joslin's Section on Cellular and Molecular Physiology, Assistant Director of Clinical Research at Joslin and Assistant Professor of Medicine at Harvard Medical School. Dr. Patti is Director of Joslin's Genomics Core Lab and also an Investigator in Cellular and Molecular Physiology and Assistant Professor of Medicine, Harvard Medical School. Dr. Crunkhorn is a postdoctoral fellow in Dr. Patti's laboratory.........

Posted by: JoAnn      Permalink         Source

February 13, 2006, 10:45 PM CT

Heart Disease-glucose Connection

Men with cardiovascular disease may be at considerably increased risk for death even when their blood sugar level remains in the "normal" range, suggests a new study by a team of researchers at UCLA and Cedars-Sinai Medical Center in Los Angeles. The study, a statistical analysis examining the correlation between glucose (blood sugar) levels and death in patients with cardiovascular disease, will be published Feb. 15 in the American Journal of Epidemiology, the leading scientific journal in its field.

Cardiovascular disease includes coronary heart disease, stroke, angina and peripheral vascular disease. Currently, doctors consider a glucose level of 100 or less to be normal, 101-126 to be impaired and above 126 to be diabetic.

"Our findings suggest that for men with cardiovascular disease, there is apparently no 'normal' blood sugar level," said Sidney Port, UCLA professor emeritus of mathematics and statistics, and lead author of the study. "For these men, across the normal range, the lower their blood sugar, the better. Their death rate over a two-year period soars from slightly more than 4 percent at a glucose level of 70 (mg/dl) to more than 12 percent at 100 (mg/dl) -- an enormous increase."

Surprisingly, however, and contrary to conventional belief, above 100 (mg/dl), their risk does not seem to change -- it stays at the same high level -- no matter how high above the normal range, Port said. Their death rate at 100 and 150 is the same. Eventhough these data suggest that blood sugar for men with cardiovascular disease should be as low as possible, co-author Mark Goodarzi, assistant professor-in-residence at Cedars-Sinai Medical Center's Division of Endocrinology, cautions that their study by no means proves that deliberately lowering glucose would reduce mortality.........

Posted by: JoAnn      Permalink         Source


February 10, 2006, 6:53 PM CT

Diabetes Control For Chinese-speaking Immigrants

Health providers helping Chinese-speaking Asian American immigrants with diabetes better control their disease to avoid complications need to do more than just have translators and bilingual staff in hospitals or doctors' offices. While that's a start, these patients also need comprehensive patient education materials written in Chinese and a medical staff thoroughly versed in the customs and cultural issues that may impede their diabetes care, as per a new study by scientists at Joslin Diabetes Center.

The Chinese-speaking immigrants who were surveyed at community health centers in Boston, New York City and Oakland, Calif., were found to have less knowledge of how to manage their diabetes - and generally had a trend toward poor blood glucose control - compared with Asian American immigrants who preferred to speak English, as per William C. Hsu, M.D., who led the pilot study along with his colleagues in Joslin's Asian American Diabetes Initiative (AADI). But after being given a bilingual diabetes education book, the participants showed improved understanding of their disease and a trend toward improved blood glucose control in laboratory tests.

The study, which appears in the recent issue of the American Diabetes Association's journal, Diabetes Care, is among the first of its kind to explore language barriers to diabetes management among Chinese-speaking immigrant populations.........

Posted by: JoAnn      Permalink    Source


January 16, 2006, 11:45 PM CT

Boosting Stem Cells to Treat Diabetes

For diabetes patients, who can't produce their own insulin, human stem cell-based transplants that produce insulin would be a major breakthrough.

But current laboratory methods of culturing human stem cells result in very limited quantities, far short of the quantities necessary for therapeutic applications.

For that reason, Emmanuel (Manolis) Tzanakakis, Ph.D., is striving to boost the numbers of stem cells produced in the laboratory, expanding the pool of cells that eventually can be differentiated into insulin-producing cells.

Tzanakakis, assistant professor in the Department of Chemical and Biological Engineering in the University at Buffalo School of Engineering and Applied Sciences, has received a $200,000 James D. Watson Investigator Grant award to support his studies from the New York State Office of Science, Technology and Academic Research (NYSTAR). He is one of six scientists throughout the state to receive the award this year.

His ultimate goal is to conduct research to develop methods that will allow sufficient quantities of differentiated cells that secrete insulin to be produced from the stem cells. Such cells could be used for diabetes therapies, including transplantation into patients, freeing them from the lifelong necessity of daily insulin injections.........

Posted by: JoAnn      Permalink


January 16, 2006, 11:34 PM CT

Pancreatic Cancer and Insulin Resistance

A new study led by scientists at the National Cancer Institute (NCI), part of the National Institutes of Health, shows for the first time that male smokers with the highest insulin levels are twice as likely to develop pancreas cancer as men with the lowest levels. Similarly, men with glucose levels in the range of clinical diabetes were twice as likely to develop the cancer as men with normal glucose levels. This study examined data from the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study* of 29,000 male smokers in Finland and appears in the December 14, 2005, issue of the Journal of the American Medical Association**.

Study researchers drew blood from enrollees when they joined the ATBC Study in the mid-1980s. This allowed the scientists to determine participants' overnight fasting insulin and glucose levels a number of years ahead of when they might be diagnosed with cancer. Over the course of 17 years, 169 men in the study developed pancreas cancer.

Study results show a two-fold increase in risk of pancreas cancer in the quartile of men with the highest fasting serum insulin levels (greater than 6.1 microinternational units per milliliter) compared to those in the lowest quartile (less than 2.75 microinternational units per milliliter). Increasing concentrations of glucose, insulin, and insulin resistance were also associated with pancreas cancer. Moreover, the risk for pancreas cancer increased with longer follow-up time.........

Posted by: Sue      Permalink


January 11, 2006, 8:00 PM CT

Link Between High-Fat Diet and Type 2 Diabetes

Howard Hughes Medical Institute scientists have discovered a molecular link between a high-fat, Western-style diet, and the onset of type 2 diabetes. In studies in mice, the researchers showed that a high-fat diet interferes with a genetic mechanism they discovered that promotes insulin production, resulting in the classic signs of type 2 diabetes.

In an article published in the December 29, 2005, issue of the journal Cell , the scientists report that knocking out a single gene encoding the enzyme GnT-4a glycosyltransferase (GnT-4a ) disrupts insulin production. Importantly, the researchers showed that a high-fat diet suppresses the activity of GnT-4a and leads to type 2 diabetes due to failure of the pancreatic beta cells.

"We have discovered a mechanistic explanation for beta cell failure in response to a high-fat diet and obesity, a molecular trigger which begins the chain of events leading from hyperglycemia to insulin resistance and type 2 diabetes," said Jamey Marth, a Howard Hughes Medical Institute investigator at the University of California, San Diego (UCSD). Marth and first author Kazuaki Ohtsubo at UCSD collaborated on the studies with scientists from the Kirin Brewery Co. Ltd., and the University of Fukui, both in Japan.

The discovery of the link between diet and insulin production offers new information that may aid in the development of therapys that target the early stages of type 2 diabetes. In its earliest phases, the disease causes failure of insulin-secreting beta cells in the pancreas, which leads to elevated blood glucose levels. As the disease progresses, the insulin-secreting beta cells overcompensate for the elevated blood glucose, and eventually pump out too much insulin. This leads to insulin resistance and full-blown type 2 diabetes.........

Posted by: JoAnn      Permalink


January 2, 2006, 9:48 PM CT

Obesity And Alzheimer's Disease

If heart disease and diabetes aren't bad enough, now comes another reason to watch your weight. As per a studyjust released, packing on too a number of pounds can increase the risk of developing Alzheimer's disease.

A team led by scientists at the Farber Institute for Neurosciences at Thomas Jefferson University in Philadelphia and Edith Cowan University in Joondalup, Western Australia has shown that being extremely overweight or obese increases the likelihood of developing Alzheimer's. They found a strong correlation between body mass index and high levels of beta-amyloid, the sticky protein substance that builds up in the Alzheimer's brain and is thought to play a major role in destroying nerve cells and in cognitive and behavioral problems associated with the disease.

"We looked at the levels of beta-amyloid and found a relationship between obesity and circulating amyloid," says Sam E. Gandy, M.D., Ph.D., director of the Farber Institute for Neurosciences. "That's almost certainly why the risk for Alzheimer's is increased," says Dr. Gandy, who is also professor of neurology, and biochemistry and molecular biology at Jefferson Medical College of Thomas Jefferson University. "Heightened levels of amyloid in the blood vessels and the brain indicate the start of the Alzheimer's process." The researchers reported their findings this month in the Journal of Alzheimer's Disease.

According to, Dr. Gandy, evidence has emerged over the last five years that a number of of the conditions that raise the risk for heart disease such as obesity, uncontrolled diabetes, high blood pressure and hypercholesterolemia also increase the risk for Alzheimer's. Yet exactly how such factors made an individual more likely to develop Alzheimer's remained a mystery.........

Daniel      Permalink