Is it possible for type 2 diabetics to someday take a natural compound daily like a food supplement to improve blood glucose levels? This is the promising discovery found by researchers at Washington University School of Medicine in St. Louis who observed that a by treating diabetic mice with a natural compound called NMN, high blood sugar levels and elevated levels of cholesterol, triglycerides and free fatty acids were reversed.
What is NMN?
Nicotinamide mononucleotide (NMN) is a naturally occurring compound in the body that plays a vital role in how cells use energy. It is involved in the synthesis of nicotinamide adenine dinucleotide (NAD), a coenzyme in cells that is essential for converting energy from nutrients into a form cells can use. NMN increases NAD which in turn activates a protein called SIRT1 to promote healthy metabolism throughout the body, particularly from the pancreas to the liver, and to muscles and fat tissue.
Experimental mice, which were fed with a high fat diet containing 42% of the total calories from fat, and found to have increased blood glucose levels (fasting blood glucose levels > 120 mg/dl) and elevated cholesterol levels, were found to have reduced NAD+. The low levels of NAD caused by defects in its biosynthesis were associated with impaired metabolism characteristic of type 2 diabetes.
Age -induced diabetic mice were likewise included in the study by screening male and female mice at 15–26 months of age with elevated fasting blood glucose levels. The mice at this age are comparable to 60-70 year old humans.
Effects of NMN Treatment
Since NAD+ cannot be given directly to the mice because of its toxic effects (serious hyperglycemia lasting for hours), the researchers used NMN instead, which resulted in the increase of NAD production in the mice.
Injecting the diabetic mice with NMN resulted in:
- Improved glucose tolerance, even after one injection
- Increased levels of NAD in female mice with normal results in glucose tolerance tests
- Reduced glucose tolerance in male mice, although blood glucose levels did not return to normal levels
- Normal glucose tolerance in older female diabetic mice
- Reversal of levels of cholesterol, triglycerides and free fatty acids to normal
In an online interview with Shin-ichiro Imai, co-author of the study, he stated that the most important potential impact of this study is two fold:
- There are significant defects in NAMPT-mediated NAD biosynthesis that contribute to the pathogenesis of diet- and age-induced type 2 diabetes
- We can significantly improve major symptoms of type 2 diabetes by supplementing an endogenous compound, NMN (nicotinamide mononucleotide; a key NAD intermediate), at least in mice.
The results of the study pave the way for further research on the possibility of utilizing a natural compound found in the body in the treatment of diabetes type 2, particularly in people who consume a high fat diet and in aging patients.
However, there are some aspects in the research which have to be studied further, such as the differences in results between male versus female mice, wherein NMN treatment resulted in reduction but not normalization of blood sugar levels in male mice as opposed to return to normal values in females. The reason proposed may be the interaction of the female hormone estrogen in the synthesis of NAD.
Another point to examine would be if these results are equally promising in human diabetic patients whose NMN mechanisms are similar to that in mice.
Finally, the research group is now conducting a long-term study on diabetic mice using NMN dissolved in water for oral intake to explore the possibility that NMN can be taken like a vitamin by people who have diabetes type 2.
Jun Yoshino, Kathryn F. Mills, Myeong Jin Yoon and Shin-ichiro Imai. Nicotinamide Mononucleotide, a Key NAD+ Intermediate, Treats the Pathophysiology of Diet- and Age-Induced Diabetes in Mice. Cell Metabolism. DOI: 10.1016/j.cmet.2011.08.014.
Julia Evangelou Strait. Natural compound helps reverse diabetes in mice.
Decoding Science. One article at a time.