UCSD Researchers Find Protein That Triggers Diabetes

Posted by Alexander Nguyen
Times of San Diego 

June 8, 2014

The origins and steps of obesity-related diabetes have been established for the first time, according to a significant set of findings just published by researchers at the UCSD School of Medicine.

The researchers concentrated on a protein, called ANT2, that they believe causes diabetes in fat people.

UCSD Skaggs School of Pharmacy & Pharmaceutical Sciences. Courtesy of UCSD News Center

“We’ve pinpointed the steps, the way the whole thing happens,” said Jerrold M. Olefsky, associate dean for Scientific Affairs and Distinguished Professor of Medicine at UCSD.

“The research is in mice, but the evidence suggests that the processes are comparable in humans and these findings are important to not just understanding how diabetes begins, but how better to treat it and prevent it.”

In a study published this weekend in the medical journal Cell, the UCSD researchers described a sequence that begins at the cellular level, as cells react to high-fat diets. These high-fat diets can then result in obesity- induced insulin resistance, and then diabetes.

Olefsky and others have previously shown that obesity is characterized by low-grade inflammation in fat tissue, and that this inflammation can become chronic and result in insulin resistance and diabetes. In their most recent findings, the scientists describe the earliest stages of the process which begin before obesity manifests itself.

The scientists began by feeding mice a high-fat diet. They noticed that the high levels of saturated fatty acids in the diet activated a protein in the fat cell membranes, which in turn caused increased oxygen consumption in the cells.

The increased oxygen consumption by the ANT2 protein left less oxygen for the rest of the cell.

Without an adequate oxygen supply, the cells go through a process that ultimately launches the immune system’s inflammatory response system. A sustained high-fat diet ensured that the process continued unimpeded, and that led to obesity, chronic tissue inflammation and insulin resistance in the mice.

The researches found that by controlling certain aspects of the process, they could protect the mice from inflammation, insulin resistance and elevated glucose levels that were caused by the high-fat diet.

The researches suggest that by impeding two specific steps in the sequence, they could blunt or even reverse the damaging cellular sequence.

— City News Service

Study found abnormal rhythms when blood sugar dipped at night in people with type 2 disease

Low Blood Sugar & Heartbeat in People With Diabetes Study found abnormal rhythms when blood sugar dipped at night in people with type 2 disease WebMD News from HealthDay By Serena Gordon April 22, 2014 Low blood sugar levels -- known as hypoglycemia -- in people with diabetes may cause potentially dangerous changes in heart rate, according to a small new study. This study's findings may help explain why a large-scale study found that very tight control of blood sugar levels in people with type 2 diabetes led to higher-than-expected death rates. It may also help explain why some otherwise healthy people with type 1 diabetes die during their sleep -- sometimes called "dead-in-bed syndrome" -- without an apparent cause, researchers say. "We found that hypoglycemia was fairly common and that nocturnal episodes in particular were generally marked by a pattern whereby glucose levels dropped to low levels for some hours during which patients slept," said Dr. Simon Heller, senior study author and a professor of clinical diabetes and honorary consultant physician at the University of Sheffield, in England. "These periods of hypoglycemia were associated with a high risk of marked slow heart rates [bradycardia] accompanied by [abnormal] beats. We have therefore identified a mechanism which might contribute to increased mortality in individuals with type 2 diabetes and high cardiovascular risk during intensive insulin therapy," Heller said. Low blood sugar levels are not uncommon in people with diabetes, a disease that can produce dangerously high blood sugar levels. That's because the very treatments that can help prevent high blood sugar levels -- and the serious complications that accompany long-term high blood sugar levels -- can cause blood sugar levels to drop too low. Although some oral diabetes medications can cause low blood sugar levels, the most common treatment to drop blood sugar levels too low is insulin. Insulin is a naturally occurring hormone that helps usher sugar into cells to be used as fuel. "Your body needs fuel to survive and run properly," said Dr. Simon Fisher, an associate professor of medicine, cell biology and physiology at Washington University in St. Louis. "During hypoglycemia, the body is low on energy. When hypoglycemia is more severe, the brain [which runs on sugar] can get confused and stop functioning. If the blood sugar gets low enough, hypoglycemia can be fatal." Fisher is also a co-author of an editorial accompanying the study in the May issue of Diabetes. Low blood sugar is a well-recognized problem for people with type 1 diabetes, who must take multiple daily injections of insulin because their bodies no longer produce the hormone, according to study author Heller. But, low blood sugar generally isn't considered to be as significant a problem in type 2 diabetes, noted Heller, who added that the researchers were somewhat surprised to see that people with type 2 diabetes had low blood sugar levels about 10 percent of the time. 1 | 2 | 3 Next Page >

Mediterranean diet may protect against diabetes

Mediterranean diet may protect against diabetes
By Andrew M. Seaman
Mon Jan 6, 2014
(Reuters Health)

Without cutting back on calories, adopting a Mediterranean diet rich in extra-virgin olive oil may protect people at high risk for heart disease against diabetes, a new study found. Researchers who analyzed data on more than 3,500 people at an increased risk for heart disease found those who were put on a Mediterranean diet were about 30 percent less likely to develop diabetes over the next four years, compared to those assigned to a general low-fat diet. "Randomized trials have shown that lifestyle interventions promoting weight loss can reduce the incidence of type 2 diabetes, however, whether dietary changes without calorie restriction or increased physical activity also protect from diabetes development has not been evaluated in the past," Dr. Jordi Salas-Salvado wrote to Reuters Health in an email. Salas-Salvado is the study's lead author and a professor of nutrition at Rovira i Virgili University and the head of the Department of Nutrition at the Hospital de Sant Joan de Reus in Spain. Previous research, including another study from Salas-Salvado and colleagues, suggested Mediterranean diets may be protective against diabetes (see Reuters Health story of October 14, 2010 here: reut.rs/1i7Rx5W. Mediterranean diets are generally high in vegetables, fiber-rich grains, legumes, fish and plant-based sources of unsaturated fat - particularly olive oil and nuts. They are low in red meat and high-fat dairy, prime sources of saturated fat. In addition to being touted as beneficial to people with heart disease, Mediterranean diets are believed to have components that reduce inflammation throughout the body and may have some impact on diabetes. Type 2 diabetes, sometimes referred to as adult-onset diabetes, is when the body's cells are resistant to insulin or the body doesn't make enough of the hormone, so glucose remains in the bloodstream and can climb to dangerously high levels. Insulin gives glucose - or blood sugar - access to the body's cells to be used as fuel. For the new study, published in the Annals of Internal Medicine, the researchers used data from an existing trial that compared the effectiveness of Mediterranean-style diets to a low-fat diet. Between 2003 and 2009, 3,541 Spaniards ages 55 to 80 were enrolled in the trial. None of the participants had diabetes at the start of the trial, but all had three or more risk factors for heart disease. Those include smoking, being overweight and having high cholesterol. The participants were randomly assigned to adopt one of three diets. One diet consisted of a Mediterranean diet that derived most of its unsaturated fat from extra-virgin olive oil. Another group was assigned a Mediterranean diet that used mixed nuts as its main source of unsaturated fat. The third diet emphasized reducing all fat consumption. None of the diets, however, asked the participants to cut down on how many calories they ate or to increase how much they exercised. After about four years, 273 of the participants had developed diabetes. That included 6.9 percent of participants from the extra-virgin olive oil group, 7.4 percent from the mixed nuts group and 8.8 percent from the reduced-fat group. The researchers caution that the difference in diabetes cases among people on the mixed nuts and reduced-fat diets may have been due to chance. They can't explain why the mixed nuts diet didn't show quite the same benefit as the extra-virgin olive oil diet. But Salas-Salvado said the difference between the two Mediterranean diets could also be a coincidence, because both have additional unsaturated fatty acids that are linked to a reduced diabetes risk. He said cutting calories along with adopting a Mediterranean-style diet would likely reduce risks even further. "These benefits have been observed in participants between 55 to 80 years old at high cardiovascular risk," he said. "Therefore, the message is that it is never too late to switch to a healthy diet like the Mediterranean." SOURCE: bit.ly/SQRXAa Annals of Internal Medicine, online January 6, 2014.

How Coffee Could Save Your Life--more benefits revealed in new research

How Coffee Could Save Your Life
Yet another reason to indulge your caffeine addiction
By Claire Groden
Time
July 26, 2013

To hear most recent research tell it, coffee is a miracle drink. The magic beans will ward off skin cancer and Alzheimer’s, reduce heart failure and diabetes risks, heighten focus, and maybe even protect liver health. Oh, and decrease suicide risk, according to the newest study that validates our coffee addictions.

According to a study performed by the Harvard School of Public Health and published this month in The World Journal of Biological Psychiatry, people who drink two to four cups of java each day are less likely to commit suicide than those who don’t drink coffee, drink decaf, or drink fewer than two cups each day. The study followed over 200,000 people for at least 16 years. And it’s not just a weak link: the researchers found that the suicide risk was cut by around 50 percent for caffeine fiends.

(MORE: Caffeine Withdrawal Is Now A Mental Disorder)

This isn’t the first time that researchers have discovered that coffee and smiles might go hand-in-hand. A 2011 study found that women who drink coffee cut their risk of depression by 15 percent compared to those who don’t. Michel Lucas, the head researcher of the most recent study, told The Huffington Post that coffee addicts can thank caffeine for the good news. The drug may actually act like a mild anti-depressant by tweaking levels of happy hormones like serotonin and dopamine.

Of course, there’s plenty of research out there that doesn’t look so kindly upon coffee drinkers. Recently, the New Yorker published an article arguing that while coffee may heighten focus, that means it also puts a squeeze on creativity. And of course, coffee’s well-known negative effects like insomnia and disturbed sleep cycles still hold.

Regardless, we’ll raise our mugs to this most recent study for giving us one more validation for our vice.

Diabetes drug metformin proves useful for other problems

Diabetes drug metformin proves useful for other problems
Karen Weintraub
USA TODAY
July 30, 2013

Early research suggests the decades-old diabetes drug metformin can slow cancer, reduce heart disease and perhaps limit the ravages of Alzheimer's. A new study shows it can extend lifespan in mice.

Could metformin, the most widely used diabetes drug in the world, be useful for fighting a number of health problems?

Early research suggests the decades-old drug can slow cancer, reduce heart disease and maybe even limit the ravages of Alzheimer's. Now, a new study in mice finds that it can extend life by a number of weeks — the human equivalent of 3-4 years.

It's far too soon for healthy people to consider taking the drug, researchers say, but the findings are provocative, and suggest science is getting closer to a day when it may be possible to pop a pill to live healthier longer.

Diseases of aging, like cancer, heart disease, type 2 diabetes and dementia are all linked along a biological pathway, researchers say. Eating less food appears to trigger that cascade, significantly extending life in animals, probably by slowing down metabolism.

Metformin is the third drug shown in early research to affect the same pathway, along with rapamycin, a powerful medication used to prevent rejection of transplanted organs; and resveratrol, a compound found in red wine.

"It's clear that we are edging toward developing a pharmaceutical intervention that is going to be able to delay or postpone aging," said Rafael de Cabo, a biogerontologist at the National Institute of Aging, who conducted the new mouse study, published today in Nature Communications. "For how much and how long I have no idea."

Brian Kennedy, CEO of The Buck Institute for Research on Aging in Novato, Calif., said he envisions a day when, instead of giving people drugs after they get sick, healthy people will be able to take pills to avoid illness. Such a pill wouldn't prevent all aging, he said, but by delaying the deadliest diseases for even a few years, it could have a dramatic benefit on an individual's quality of life and the nation's economy.

Despite their optimism, both Kennedy and de Cabo said that healthy people should not be taking metformin at this point. While mice are a good model for diseases, they do not respond exactly as people do; and they live a totally controlled life inside a cage, de Cabo said.

Metformin caused severe kidney problems in mice taking a high dose, suggesting that researchers need to proceed with caution when testing the drug in people, de Cabo said. Even the low dose used in his study left mice with more drug in their bloodstream than diabetics get on their metformin regimen, so it's not yet clear what dose to use in healthy people.

The drug is also known to cause diarrhea, because it affects the metabolism of sugars in the digestive system.

So far, those two side effects have kept researchers from trying the drug on themselves. David Sinclair, a genetics professor at Harvard Medical School who has done extensive research on resveratrol, said he took metformin along with his resveratrol for a short time. He stopped when he saw the toxic effects in this mouse study, which he co-authored. He said he wouldn't take rapamycin because of its side effects.

A new drug will eventually be developed, he predicted, that will amplify the benefits of these drugs and minimize their side effects.

"In terms of history, we're still at the very early stages of understanding how to slow aging in a safe way," said Sinclair.

Even if it turns out not to extend life, metformin has shown powerful results in other areas of research:

• Kevin Struhl, a molecular and cancer biologist at Harvard Medical School, said he has been impressed by early studies showing metformin's effectiveness at treating cancer and stopping cells from turning cancerous in the first place.

• At the University of Pennsylvania, Alzheimer's expert Steven Arnold is studying the drug's ability to slow or prevent mental decline.

• And other work has shown that metformin can help stop pre-diabetes before it turns into type 2 diabetes, said Karin Hehenberger, a molecular biologist, diabetes expert and chief medical officer at Coronado Biosciences, a Massachusetts biotech company focused on autoimmune diseases.



In terms of aging, we already know enough to help people until a pill can be developed, Kennedy said.

"There's a huge secret to (combating) aging right now," he said. "That's eat right and exercise."

Imbalances in the microbial community in your intestines may lead to metabolic syndrome, obesity, and diabetes.

Are Happy Gut Bacteria Key to Weight Loss?
Imbalances in the microbial community in your intestines may lead to metabolic syndrome, obesity, and diabetes. What does science say about how to reset our bodies?
By Moises Velasquez-Manoff
Mother Jones
Apr. 22, 2013

A few years before Super Size Me hit theaters in 2004, Dr. Paresh Dandona, a diabetes specialist in Buffalo, New York, set out to measure the body's response to McDonald's—specifically breakfast. Over several mornings, he fed nine normal-weight volunteers an egg sandwich with cheese and ham, a sausage muffin sandwich, and two hash brown patties.

Dandona is a professor at the State University of New York-Buffalo who also heads the Diabetes-Endocrinology Center of Western New York, and what he observed has informed his research ever since. Levels of a C-reactive protein, an indicator of systemic inflammation, shot up "within literally minutes." "I was shocked," he recalls, that "a simple McDonald's meal that seems harmless enough"—the sort of high-fat, high-carbohydrate meal that 1 in 4 Americans eats regularly—would have such a dramatic effect. And it lasted for hours.

Inflammation comes in many forms. The swelling of a sprained ankle indicates repairing torn muscle and tendon. The redness and pain around an infected cut signifies the body's repulsion of microbes. The fever, aches, and pains that accompany the flu represent a body-wide seek-and-destroy mission directed against an invading virus. They're all essential to survival, the body's response to a perceived threat or injury. But inflammation can also cause collateral damage, especially when the response is overwhelming—like in septic shock—or when it goes on too long.

Chronic, low-grade inflammation has long been recognized as a feature of metabolic syndrome, a cluster of dysfunctions that tends to precede full-blown diabetes and that also increases the risk of heart disease, stroke, certain cancers, and even dementia—the top killers of the developed world. The syndrome includes a combination of elevated blood sugar and high blood pressure, low "good" cholesterol, and an abdominal cavity filled with fat, often indicated by a "beer belly." But recently, doctors have begun to question whether chronic inflammation is more than just a symptom of metabolic syndrome: Could it, in fact, be a major cause?

For Dandona, who's given to waxing grandiloquent about the joys of a beer on the porch in his native Delhi, or the superb ice wines from the Buffalo region, the results presented a quandary. Food was a great pleasure in life. Why would Nature be so cruel, he wondered, and punish us just for eating?

Over the next decade he tested the effects of various foods on the immune system. A fast-food breakfast inflamed, he found, but a high-fiber breakfast with lots of fruit did not. A breakthrough came in 2007 when he discovered that while sugar water, a stand-in for soda, caused inflammation, orange juice—even though it contains plenty of sugar—didn't.

The Florida Department of Citrus, a state agency, was so excited it underwrote a subsequent study, and had fresh-squeezed orange juice flown in for it. This time, along with their two-sandwich, two-hash-brown, 910-calorie breakfast, one-third of his volunteers—10 in total—quaffed a glass of fresh OJ. The non-juice drinkers, half of whom drank sugar water, and the other half plain water, had the expected response—inflammation and elevated blood sugar. But the OJ drinkers had neither elevated blood sugar nor inflammation. The juice seemed to shield their metabolism. "It just switched off the whole damn thing," Dandona says. Other scientists have since confirmed that OJ has a strong anti-inflammatory effect...

Coffee good for you, but it's OK to hold back

Coffee good for you, but it's OK to hold back
By Elizabeth Landau
CNN
August 18, 2012

A study last year found a lower risk of endometrial cancer in coffee-drinking women. Coffee may prevent type II diabetes and Parkinson's disease, evidence shows It may also have anti-cancer and antidepressant effects

If you can't get through your day without a coffee break or two, here's good news for you: What scientists know so far suggests coffee may help you stay healthy.

As usual with medical research, the operative word is "may."

It's hard to know for sure whether coffee is really causing good effects -- lifestyles or behaviors associated with coffee consumption may also influence health. Also, different people have different tolerances for coffee -- it can have short-term side effects that make people steer clear of morning brews.

So, doctors aren't quite convinced enough to prescribe coffee -- but they probably don't need to, because so many people indulge in it anyway.

The point is: In general, regular coffee drinkers won't be discouraged from continuing the habit, although there are exceptions.

"For most people, for people who don't experience the side effects, the benefits far outweigh the risks," said Dr. Donald Hensrud of the Mayo Clinic.

Why would coffee be good?

More is known about the overall association between coffee and positive health effects than about the mechanism behind it, said Dr. Alberto Ascherio, professor of epidemiology and nutrition at the Harvard School of Public Health.

Antioxidants are one potential reason that good outcomes are seen from coffee. Our bodies produce oxygen radicals, which are damaging to DNA. Antioxidants prevent them from doing damage, Ascherio said.

Although antioxidants are found in fruits and vegetables, research has shown that coffee is the top source of antioxidants for Americans.

Caffeine itself may also contribute to coffee's positive effects on brain health. That may be because caffeine is an antagonist to adenosine receptors. These receptors normally slow down neural activity when the chemical adenosine binds to them, producing a sleepy feeling. But if caffeine binds to the receptors, the activity of neurons speeds up.

Coffee also appears to lower levels of insulin and estrogen, which is perhaps why a study last year found a lower risk of endometrial cancer in coffee-drinking women. Insulin also plays a role in prostate cancer, another disease coffee may help stave off.

What good it may bring

The evidence is fairly strong for coffee preventing type II diabetes and Parkinson's, and reasonably good for antidepressant effects, too, doctors say.

Just in the last few months, several new studies have been published highlighting other possible benefits of coffee. Again, none of them prove that coffee causes any effects at all; they are just associations.

People who drink two 8-ounce cups of coffee daily appear to have an 11% lower risk of developing heart failure, compared to noncoffee drinkers. That's according to a meta-analysis published in June in the American Heart Association's journal Circulation: Heart Failure, based on pooling the results of five studies. The researchers did not take into account the strength of coffee, what time of day it was drunk, or whether it was caffeinated -- factors that could be related.

Coffee drinkers may also be protecting themselves against basal cell carcinoma, the most common form of skin cancer, according to a July report in the journal Cancer Research. Other caffeinated beverages also seemed to reduce the risk of this slow-growing cancer. But scientists don't yet know why this effect was observed.

Increased coffee consumption also is associated with longer life, according to Research in the New England Journal of Medicine. Again, no one knows what about coffee would make people live longer, but Ascherio theorizes it could be the protection against type II diabetes, Parkinson's, depression and suicidal tendencies.

Some of the strongest evidence comes from studies on type II diabetes. According to a 2009 meta-analysis, the risk of type II diabetes goes down with each cup of coffee consumed daily. Additionally, a 2007 meta-analysis found a correlation between increased coffee consumption and lower risk of liver cancer. But it's not enough to tell anyone who doesn't already drink coffee to start.

There have not been any large randomized controlled trials regarding coffee's health benefits, or even to see whether caffeinated or decaf is better for you. Without this kind of research, there will be uncertainty.

While perhaps scientifically interesting, such an investigation hasn't happened because of the economics involved, Ascherio said. A trial could cost in the tens of millions of dollars. Pharmaceutical companies aren't in the business of selling coffee, and coffee makers don't need a study to market their products -- people who like coffee buy it anyway.

How much coffee a person can drink daily varies widely; some people don't feel any side effects.

The optimal daily dose of coffee varies widely, depending on the person. Some can't drink it at all. Others tolerate six to eight cups a day.

As common sense might suggest, the greatest overall benefits appear to be in people who drink coffee at moderate levels: two to three cups a day. But there are exceptions: A May 2011 study found that men who drink six or more cups a day had a decreased risk of fatal prostate cancer.

The bad stuff

Coffee hasn't always been hailed as such a great thing. It's also not for everyone. Doctors may never consider coffee a standard recommendation because of individuals' varying susceptibility to side effects, said Hensrud.

Those include headaches, insomnia, heartburn and palpitations, not to mention urinary urgency. People who get fast heartbeats may need to steer clear of caffeinated coffee, too. Others don't drink coffee because it irritates their stomachs.

Famously, coffee got a bad reputation from research in the early 1980s connecting it to pancreatic cancer. But more recent studies have not found the same link, according to the American Cancer Society.

Some studies in the past did not take into account the connection between drinking coffee and smoking cigarettes, which do contain carcinogens, Hensrud said. Different people metabolize caffeine differently, so some people can have a cup of coffee at night and fall asleep right away, while others need to keep their distance from java for several hours before bedtime to avoid insomnia.

Coffee that's boiled -- popular in Scandinavia, for instance -- will increase bad cholesterol; espresso has the same effect, Hensrud said. But filtering regular coffee reduces those cholesterol-raising substances...

Why Working the Night Shift May Boost Your Risk of Diabetes

Why Working the Night Shift May Boost Your Risk of Diabetes
By Alice Park
Time
December 7, 2011

The night shift isn't usually anyone's first choice, but in some professions — and in this economy — it can't be avoided. About 26% percent of the American workforce, including health-care workers and sanitation staff, clocks in after dark, and the schedule may be taking a toll on their health.

Past research has shown that working when you're supposed to be in bed disrupts your circadian rhythm, raising the risk of heart disease, obesity, ulcers and even depression. Now, reporting in the journal PLoS Medicine, scientists also find that rotating night-shift work can increase the risk of developing Type 2 diabetes. The backward schedule can mess with the body's ability to use insulin properly to break down sugars in the blood, according to Dr. Frank Hu, a professor of nutrition and epidemiology at Harvard School of Public Health.

In a study involving nearly 177,000 middle-aged women enrolled in two Nurses' Health Studies, women who worked rotating night shifts for 1 to 2 years increased their risk of developing diabetes by 5% over a 20-year follow-up period, compared with women who didn't get assigned these shifts. Women who kept up night work for 10 to 19 years increased their risk by 40%. Working on and off at night for more than 20 years boosted the risk of diabetes by 60%.

Certainly, body weight is part of the problem, since excess weight is a risk factor for diabetes. People who work at night may snack more when they should be sleeping — and our bodies are metabolically trained to slow down as the sun sets. So the calories we take in during the evening and night hours are less likely to get burned off efficiently, and more likely to be stored as fat.

It's not just night work that causes a problem. Simply not sleeping when you're supposed to, or not getting enough sleep, can also wreak havoc with your metabolism, by pushing up levels of the appetite-stimulating hormone ghrelin and suppressing the appetite-curbing hormone leptin. Our circadian clocks also regulate body weight indirectly, by controlling body temperature and blood glucose levels. "The bottom line is there are probably multiple mechanisms through which disrupted sleep patterns or long term rotating night shift work can influence the risk of Type 2 diabetes," says Hu.

The study focused on people who rotated night shift work, so they weren't working nights routinely, but perhaps once every few days or weeks. Hu says it's not clear whether those who regularly work at night (and therefore sleep during the day) can adjust their body clocks to avoid this increased risk of diabetes.

What intrigued Hu and his team the most was the cumulative effect that night work had on diabetes risk. The longer people worked irregular hours at night, the higher their risk of developing the disease. "It's something people should keep in mind," he says. "If they minimize or reduce the time they work on night shifts, they may be able to attenuate their risk."

That's an important lesson for those who have to work at night. They might not be able to avoid the late hours, but they should remember that sticking with a night shift schedule for too long can be harmful for their health. And because these individuals may be at higher risk of developing diabetes, they should pay more attention to things that can lower their risk, such as watching their diet, exercising and getting screened for the disease more regularly.

When Fat Makes You Healthy: Subcutaneous Fat May Produce Beneficial Hormones

When Fat Makes You Healthy: Subcutaneous Fat May Produce Beneficial Hormones
May 22, 2008
Diabetes Health

It has long been known that type 2 diabetes is linked to obesity, particularly fat inside the belly. Now, researchers at the Joslin Diabetes Center have found that fat from other areas of the body can actually reduce insulin resistance and improve insulin sensitivity.

In a study published in the May issue of Cell Metabolism, a team lead by C. Ronald Kahn, M.D., found that subcutaneous fat—fat below the skin (usually in the hips and thighs)—is associated with reduced insulin levels and improved insulin sensitivity.

Kahn says that fat in the belly increases the risk of diabetes and mortality and it has been suggested that obesity in subcutaneous areas, often the hips and thighs, might decrease such risks.

His study concludes that fat under the skin is intrinsically different from visceral fat (belly fat or fat packed in between organs) and may produce substances that can improve glucose metabolism.

“The surprising thing was that it wasn’t where the fat was located,” Kahn said. “It was the kind of fat that was the most important variable. Even more surprising, it wasn’t that belly fat was exerting negative effects, but that fat under the skin was producing a good effect. Animals with more of this kind of fat didn’t gain as much weight as they aged, had better insulin sensitivity, lower insulin levels, and were improved all around.”

In addition, Kahn noted that a class of diabetes drugs called thiazoladinediones (ACTOS, Avandia) may cause patients to gain weight in the subcutaneous area, yet also improve insulin sensitivity.

Kahn said it is possible that fat underneath the skin may be producing certain hormones, known as adipokines, that produce beneficial effects on metabolism. These effects may offset the negative effects produced by belly fat.