Nobiletin in Tangerines Fights Obesity and Protects against Heart Disease

New research has discovered a substance in tangerines not only prevents obesity, but also offers protection against Type 2 diabetes, and even atherosclerosis....

Murray Huff, a vascular biology scientist at the Schulich School of Medicine & Dentistry, studied the effects of a flavonoid in tangerines called Nobiletin. In a model of metabolic syndrome developed by the Huff laboratory at the Robarts Research Institute, mice were fed a "western" diet high in fats and simple sugars. One group became obese and showed all the signs associated with metabolic syndrome: elevated cholesterol and triglycerides, high blood levels of insulin and glucose, and a fatty liver. These metabolic abnormalities greatly increase the risk of cardiovascular disease and Type 2 diabetes.

The second group of mice, fed the exact same diet but with Nobiletin added, experienced no elevation in their levels of cholesterol, triglycerides, insulin or glucose, and gained weight normally. Mice became much more sensitive to the effects of insulin. Nobiletin was shown to prevent the buildup of fat in the liver by stimulating the expression of genes involved in burning excess fat, and inhibiting the genes responsible for manufacturing fat.

"The Nobiletin-treated mice were basically protected from obesity," says Huff, the Director of the Vascular Biology Research Group at Robarts. "And in longer-term studies, Nobiletin also protected these animals from atherosclerosis, the buildup of plaque in arteries, which can lead to a heart attack or stroke. This study really paves the way for future studies to see if this is a suitable treatment for metabolic syndrome and related conditions in people."

Huff's research has focused on the pharmacological properties of naturally-occurring bioactive molecules. Two years ago, his research drew international attention when he discovered a flavonoid in grapefruit called Naringenin offered similar protection against obesity and other signs of metabolic syndrome. Huff says, "What's really interesting to us is that Nobiletin is ten times more potent in its protective effects compared to Naringenin, and this time, we've also shown that Nobiletin has the ability to protect against atherosclerosis."

Diabetes, April 2011

Why Don't People Take Their Insulin as Prescribed?

Risk factors differed between Type 1 and Type 2 diabetic patients, with diet nonadherence more prominent in Type 1 diabetes and….

The purpose of this study was to assess factors associated with patient frequency of intentionally skipping insulin injections, according to researcher Mark Peyrot, PhD.

Data were obtained through an internet survey of 502 U.S. adults self-identified as taking insulin by injection to treat Type 1 or Type 2 diabetes. Multiple regression analysis assessed independent associations of various demographic, disease, and injection-specific factors with insulin omission.

Intentional insulin omission was reported by more than half of respondents; regular omission was reported by 20%. Risk factors differed between Type 1 and Type 2 diabetic patients, with diet nonadherence more prominent in Type 1 diabetes and age, education, income, pain, and embarrassment more prominent in Type 2 diabetes. It is not surprising that non-compliance in Type 1 diabetes patients was associated with poor eating habits. The researchers found that younger age, lower income, and embarrassment were the most important factors for poor compliance in people with Type 2 diabetes.

Whereas most patients did not report regular intentional omission of insulin injections, a substantial number did. The findings suggest that it is important to identify patients who intentionally omit insulin and be aware of the potential risk factors identified here. For patients who report injection-related problems (interference with daily activities, injection pain, and embarrassment), providers should consider recommending strategies and tools for addressing these problems to increase adherence to prescribed insulin regimens. This could improve clinical outcomes. Although the results address the needed educational intervention, especially when it comes to embarrassment, pain, and interference with activities, it also points to the fact that healthcare teams need to talk with patients before this becomes a common practice, rather than a single occurrence.

Diabetes Care, Feb. 2011