Natural enzyme NMN helps reverse type 2 diabetes in mice
A natural compound found in the body, called nicotinamide mononucleotide, or NMN, is found to help diabetic help mice restore normal blood sugar metabolism. NMN is an enzyme that helps the body’s cells use energy that may work in humans to prevent or reverse type 2 diabetes.
Nicotinamide “remarkable” for improving diabetic symptoms
Shin-ichiro Imai, MD, PhD, associate professor of developmental biology at Washington University School of Medicine in St. Louis said the effect of nicotinamide for controlling diabetic symptoms in mice was “remarkable”.
The compound had a more potent effect in females, said Imai. “After giving NMN, glucose tolerance goes completely back to normal in female diabetic mice.”
For the study, published in the journal Cell Metabolism, researchers injected older diabetic mice with NMN.
Kathryn F. Mills, research lab supervisor and an equally contributing first author of the study said, “We also injected older healthy mice and found that they weren’t adversely affected. It’s good to know that even if the mice are not diabetic, giving NMN is not going to hurt them.”
Consuming a high fat diet and aging are contributors to diabetes. The researchers say a fatty diet and aging is also associated with lower levels of nicotinamide mononucleotide.
NMN is vital for the production of nicotinamide adenine dinucleotide, or NAD, which is an oxidizing agent that has several roles in metabolism.
One of the functions of NAD is activation of a protein called SIRT that boosts insulin sensitivity in the body.
The authors say NMN acts the same in humans and mice. "But whether this mechanism is equally compromised in human patients with type 2 diabetes is something we have to check,” Imai says. “We have plans to do this in the very near future.”
First author Jun Yoshino, MD, PhD, postdoctoral research associate, says the effect of the naturally occurring compound for controlling diabetes in mice is “much bigger than other known compounds or chemicals.”
In younger healthy mice with diabetes induced by a high fat diet, NMN boosted NAD levels to normal levels in females, but not completely in males.
The researchers say they’re not certain why. “…sex hormones, such as estrogen, may be important downstream for NAD synthesis.” Yoshino says.
The investigators are studying the effect of the natural compound on diabetic mice when it’s added to their drinking water
In the current study, one injection of nicotinamide mononucleotide reversed symptoms of diabetes by returning glucose tolerance to normal in the female mice. “Once we can get a grade of NMN that humans can take, we would really like to launch a pilot human study,” Imai says.
The compound also improved lipid profiles in the mice.
The discovery could mean humans could take a pill, much like a daily vitamin, to prevent or reverse type 2 diabetes.
The compound NMN, made naturally in the body, declines with age and when a high fat diet is consumed. Restoring levels of nicotinamide to normal could be an effective type 2 diabetes prevention or treatment that might also work in humans.
"Nicotinamide Mononucleotide, a Key NAD+ Intermediate, Treats the Pathophysiology of Diet- and Age-Induced Diabetes in Mice"
Jun Yoshino et al