Apple Peel Compound Boosts Brown Fat, Reduces Obesity in Mice

Obesity and its associated problems such as diabetes and fatty liver disease are increasingly common global health concerns. A new study by University of Iowa researchers shows that a natural substance found in apple peel can partially protect mice from obesity and some of its harmful effects.

The findings suggest that the substance known as ursolic acid reduces obesity and its associated health problems by increasing the amount of muscle and brown fat, two tissues recognized for their calorie-burning properties.

The study, which was published June 20 in the journal PLoS ONE, was led by Christopher Adams, M.D., Ph.D., UI associate professor of internal medicine and a Faculty Scholar at the Fraternal Order of Eagles Diabetes Research Center at the UI.

"From previous work, we knew that ursolic acid increases muscle mass and strength in healthy mice, which is important because it might suggest a potential therapy for muscle wasting," Adams says. "In this study, we tested ursolic acid in mice on a high-fat diet -- a mouse model of obesity and metabolic syndrome. Once again, ursolic acid increased skeletal muscle. Interestingly, it also reduced obesity, pre-diabetes and fatty liver disease.

"Since muscle is very good at burning calories, the increased muscle in ursolic acid-treated mice may be sufficient to explain how ursolic acid reduces obesity. However, we were surprised to find that ursolic acid also increased brown fat, a fantastic calorie burner. This increase in brown fat may also help protect against obesity."

Until quite recently, researchers believed that only infants had brown fat, which then disappeared during childhood. However, improved imaging techniques have shown that adults do retain a very small amount of the substance mostly in the neck and between the shoulder blades. Some studies have linked increased levels of brown fat with lower levels of obesity and healthier levels of blood sugar and blood lipid, leading to the suggestion that brown fat may be helpful in preventing obesity and diabetes...

Take your exercise pill

Scientists may be able to come up with a pill that makes you want to exercise, thus solving -- sort of -- the nation's obesity epidemic. Swiss researchers have found that by elevating a hormone --erythropoietin (Epo) -- in mice, they were more motivated to exercise. To make this discovery, Gassmann and colleagues used three types of mice: those that received no treatment, those that were injected with human Epo, and those that were genetically modified to produce human Epo in the brain. Compared to the mice that did not have any increase in Epo, both mouse groups harboring human Epo in the brain showed significantly higher running performance without increases in red blood cells. "If you can't put exercise in a pill, then maybe you can put the motivation to exercise in a pill instead," said Gerald Weissmann, M.D., Editor-in-Chief of The FASEB Journal. "As more and more people become overweight and obese, we must attack the problem from all angles. Maybe the day will come when gyms are as easily found as fast food restaurants."...

Tree oil may combat obesity, diabetes, S&T research suggests

A future weapon in the battle against obesity and diabetes could come in the form of an oil derived from the seeds of wild almond trees, according to researchers at Missouri University of Science and Technology. The key to the oil's potential lies in its ability to affect certain microorganisms living in our bellies. In a study presented today (Monday, June 18, 2012) at the American Society for Microbiology's general meeting in San Francisco, Missouri S&T researchers reported that adding sterculic oil to the diets of obese laboratory mice increased their sensitivity to insulin. This was due to the oil's effect on three types of microorganisms that live in the guts of the mice...

Higher dose of milk vitamin fights obesity

A novel form of vitamin B3 in milk given in a high dose to mice fed a fatty diet seemed to help prevent obesity, U.S. and Swiss researchers said. Dr. Anthony Sauve of Weill Cornell Medical College in New York and Dr. Johan Auwerx of Federal Polytechnic School in Lausanne, Switzerland, said high doses of the vitamin precursor, nicotinamide riboside -- a cousin of niacin -- prevented obesity in mice fed a fatty diet and also increased muscle performance, improved energy expenditure and prevented diabetes development, all without side effects. This form of vitamin B3 is found in milk in small quantities...

Fat-busting, super diet pill could help beat obesity by preventing those hunger pangs

A super diet pill aimed at curbing fat people's appetites could soon be a reality thanks to boffins who have found the secret to tackling obesity may lie in the brain. The pill would not only shrink waist lines but also the £4.2 billion NHS bill for treating obesity related illness such as cancer, diabetes and heart disease. Scientists in the US believe the hypothalmus area of the brain - a receptor controlling body temperature, hunger, thirst and fatigue - is particularly sensitive to drugs which could hold the key to fighting flab. Professor Domenico Accili, from Columbia University Medical Center, said: 'We've identified a receptor that is immediately involved in regulating food intake. 'What is especially encouraging is that it is a highly 'druggable' target. In fact, several existing medications already seem to interact with this receptor.' The researchers, whose findings are published in the Cell journal, studied insulin and leptin hormones, which inhabit the AgRP molecule and are vital to maintaining the body's energy balance. They did so by creating a strain of mice to explore the effects of appetite stimulation and discovered a gene called Gpr17. The scientists found that when the gene was injected into normal rodents, it resulted in an increase in appetite and a decrease when it was blocked - without negative side effects...

The miracle molecule: Hidden vitamin found in BEER and MILK can make you stronger, slimmer and healthier

If you were planning on having a quick pint tonight, then this will be welcome news. Beer may contain a vitamin which can fight obesity and improve muscle strength, scientists claim. The ‘miracle molecule’, which has been found in milk and may also be present in beer and some foods, has no side effects and could even lengthen lifespan, they say. The snag is that the molecule, called nicotinamide riboside (NR), is extremely small, difficult to find and expensive to synthesise. Johnan Auwerx, head of the Ecole Polytechnique Federale in Lausanne, Switzerland, said experiments using mice revealed the molecule’s potential. In an article in the specialist journal Cell Metabolism journal, Mr Auwerx called the results 'impressive' 'NR appears to play a role in preventing obesity,' said Mr Auwerx. Working with Weill Cornell Medical College in New York, his team found mice on a high-fat diet that were fed NR gained significantly less weight – 60 per cent – than mice eating the same diet without NR supplements. And none of the NR-treated mice had indications that they were developing diabetes, unlike the untreated mice. Mice which were fed NR supplements over a ten-week period had better endurance performance than those who were not...

Improving obesity-induced insulin sensitivity

In recent years, a growing body of evidence has linked inflammation to the development of insulin resistance. In insulin resistance, the hormone insulin is less effective in promoting glucose uptake from the bloodstream into other tissues. Obesity is a major factor that contributes to insulin resistance, which can eventually lead to type 2 diabetes. Previous studies have shown that proinflammatory molecules found in fat tissue decreases sensitivity of tissues to insulin. To identify drug targets that will improve insulin sensitivity, Dr. Jerrold Olefsky and colleagues from the University of California in San Diego investigated the role of G protein-coupled receptor 21 (GPR21) in insulin resistance and energy homeostasis. The group compared mice without the gene encoding GPR21 to healthy control mice under normal and high-fat diet conditions. They discovered that mice lacking GPR21 had enhanced insulin sensitivity and increased energy expenditure independent of diet. This result was attributed to the reduced migration of inflammatory cells to the liver and fat tissue in the absence GPR21. Under normal diet, absence of GPR21 in the hypothalamus caused a modest decrease in body weight. This is the first study to demonstrate the negative impact of GPR21 on inflammation and insulin sensitivity. Their findings suggest that GPR21 inhibition may improve insulin resistance and enhance energy expenditure, making GPR21 inhibitors promising treatments for diabetes.

Is There a 'Healthy' Obesity Gene?

Why is it that some obese people are healthier than others? This was one of the main questions Dr. Chaodong Wu of the College of Agriculture and Life Sciences -- Texas A&M University System -- and a group of researchers tried to answer in a recent study. The study, which will appear in a July issue of the Journal of Biological Chemistry, used genetically modified mice to investigate the genetic aspects of why some obese people do not develop certain medical problems typically associated with obesity, especially Type 2 diabetes. Wu noted that Xin Guo, a Ph.D. candidate in the college's department of nutrition and food sciences, contributed significantly to the study. "Previous research had indicated that a regulatory enzyme which is encoded by the gene PFKFB3 protects against diet-induced fat tissue inflammation and systemic insulin resistance," said Wu, who also has a Texas AgriLife Research appointment. "Increasing evidence shows that fat deposition, or amount, is not directly associated with the inflammation or insulin resistance in the development of obesity-related metabolic diseases." Wu said the inducible 6-phosphorofructo-2-kinase (iPFK2) enzyme links metabolic and inflammatory responses and may underlie what he refers to as "healthy" obesity. "While many obese people develop Type 2 diabetes, heart conditions and other chronic health problems associated with being significantly overweight, other obese people do not," he said. "And while obesity in general is not healthy, some obese people do not develop the diseases more commonly associated with a less-than-healthy diet. Furthermore, a number of thinner people may have the sort of health problems more typically associated with obesity." Wu said he and the other researchers theorized that these diseases are associated with the cellular inflammatory response brought on by obesity. "We also thought this gene could conceivably be targeted for use in the treatment of diabetes, especially Type 2, commonly associated with obesity," he said. "We wanted to find out what might happen to a subject if that particular gene was activated." Wu and his fellow researchers used laboratory mice to explore the effect of a targeted adipocyte overexpression of the gene/enzyme combination on diet-induced inflammatory responses and insulin sensitivity...

Timing of meals is tied to obesity

Gaining weight is not just the result of the number of calories eaten but also may have to do with the time of day those calories are consumed, at least in mice. The researchers, from the Salk Institute in California and elsewhere, fed the mice a high-fat diet or a standard diet. Some of the mice were allowed to eat only within an eight-hour period each day and the others were given an unrestricted amount of time to eat. When mice on the high-fat diet were restricted to eating within eight hours, they consumed just as much as those on the same diet who were permitted to eat around the clock. However, the mice with unrestricted eating times were more likely to become obese or have other metabolic disorders.