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NMN corrects type 2 diabetes

Researchers at Washington University School of Medicine in St. Louis have restored normal blood sugar metabolism in diabetic mice using a compound the body makes naturally. The finding suggests that it may one day be possible for people to take the compound much like a daily vitamin as a way to treat or even prevent type 2 diabetes.

RESEARCHERS AT WASHINGTON UNIVERSITY SCHOOL OF MEDICINE IN ST. LOUIS HAVE BEEN ABLE TO RESTORE NORMAL GLUCOSE METABOLISM IN MICE WITH TYPE 2 DIABETES BY GIVING THE ANIMALS A SUBSTANCE THAT’S ALREADY MADE IN THE BODY. THEY SAY THE FINDING COULD BE AN EARLY STEP IN A NEW STRATEGY FOR TREATING TYPE 2 DIABETES. JIM DRYDEN HAS THE STORY…

TYPE 2 DIABETES IS ASSOCIATED WITH AGING AND WITH OBESITY. THOSE WHO DEVELOP THE CONDITION TEND TO BE OLDER AND HEAVIER, AND EVENTUALLY THEIR INSULIN DOESN’T WORK WELL ENOUGH TO CONTROL THEIR BLOOD SUGAR. NOW, WORKING IN MICE, THE RESEARCHERS HAVE SUCCESSFULLY ELIMINATED DIABETES SYMPTOMS. ACCORDING TO WASHINGTON UNIVERSITY MOLECULAR BIOLOGIST SHINICHIRO IMAI, ONE OF THE IMPORTANT PARTS OF THE FINDING IS THAT THE STRATEGY RESTORED NORMAL GLUCOSE METABOLISM AND INSULIN FUNCTION BOTH IN MICE WHO HAD DEVELOPED DIABETES AFTER EATING A HIGH-FAT DIET, AND IN MICE WHO DEVELOPED DIABETES AS A CONSEQUENCE OF AGING.

(act) :26 o/c age considerably

We actually employed two models: One is a high-fat, diet-induced

type 2 diabetes, and the other is actually age-induced type 2

diabetes. And I can’t recollect, actually, any paper reporting

on an age-induced type 2 diabetes model because it takes time.

You have to let the mice age considerably.

WHAT IMAI’S TEAM DID WAS TO LOOK AT GENETIC AND MOLECULAR PATHWAYS IN THE PANCREAS, THE LIVER AND IN MUSCLE TISSUE, CONCENTRATING INITIALLY ON THE PROTEIN SIRT1. SIRT1 IS NOT ONLY LINKED TO AGING BUT ALSO TO PROBLEMS ASSOCIATED WITH AGING, LIKE TYPE 2 DIABETES. IN THE ALPHABET SOUP OF PROTEINS AND MOLECULES ASSOCIATED WITH THE AGING PATHWAY, IMAI’S TEAM FOUND THAT BY GIVING THE MICE A NATURALLY OCCURRING SUBSTANCE CALLED NMN, THEY COULD MAKE THE MICE PROCESS GLUCOSE NORMALLY. FIRST AUTHOR JUN YOSHINO SAYS IN YOUNG MICE WHO ATE HIGH-FAT DIETS AND DEVELOPED DIABETES, NMN QUICKLY RESTORED NORMAL GLUCOSE METABOLISM.

(act) :08 o/c glucose intolerance

If we give NMN, this NMN completely normalized their glucose

intolerance.

AND BECAUSE THE LABORATORY STUDIES PROBLEMS ASSOCIATED WITH AGING, THEY ALSO HAD DISCOVERED THAT SOME OLDER MICE DEVELOP DIABETES. IN THOSE MICE, CO-INVESTIGATOR KATHRYN MILLS FOUND THAT AGAIN, NMN FIXED THEIR GLUCOSE METABOLISM.

(act) :05 o/c one injection

They showed us an improved glucose tolerance test, even after

one injection.

AND IMAI SAYS BECAUSE NMN IS A NATURALLY OCCURRING SUBSTANCE, IT DIDN’T MAKE THE MICE SICK. SO IMAI BELIEVES NMN MAY SOMEDAY BE TESTED AS A THERAPY IN PEOPLE WITH DIABETES, OR EVEN USED LIKE A VITAMIN TO TRY TO PREVENT THE PROBLEM. HE SAYS IT CERTAINLY DID THE JOB IN MICE.

(act) :16 o/c an effect

This is a really remarkable result. And their glucose tolerance

goes back to completely normal in females. While in males we see

an effect, but it’s much milder, but still, you know, there is

an effect.

IMAI THEORIZES THAT DIFFERENCES BETWEEN MALES AND FEMALES MAY BE LINKED TO SEX HORMONES, BUT THAT WILL REQUIRE FURTHER STUDY. THE RESEARCHERS REPORTED THEIR FINDINGS FROM THIS STUDY IN THE JOURNAL CELL METABOLISM. I’M JIM DRYDEN…

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