Experimental Alzheimer's Drug Found To Trigger Fat Burning Without Diet

An enzyme inhibitor developed by Pfizer and tested as a potential Alzheimer's treatment is the subject of a new study, but it has nothing to do with memory. Rather, the researchers found that inhibiting an enzyme called PDE9 caused overweight mice to burn a considerable amount of fat without changes to their diet and activity level...though there was one very big catch.

The new study, it should be noted, involved mice, not humans, and additional research on humans would be necessary to determine whether a similar product could one day be developed to treat obesity in people. In this case, the study involved male and female mice; some of the female mice had their ovaries removed while others remained intact.

The study, which comes from Johns Hopkins University, involved feeding lab mice a high-fat diet; after four months of eating it, the mice doubled their body weight in addition to developing diabetes and high blood lipid levels. Some of the mice also had pressure stress on the heart intended to mimic the effects of cardiometabolic syndrome.

Some of the mice were given a placebo while the other mice were given the PDE9 enzyme inhibitor. While this drug didn't end up proving to be a useful Alzheimer's treatment, the researchers found that it did lead to notable weight loss in the mice without reducing their lean body mass or requiring diet/activity changes.

The male mice experienced a median 19.5-percent weight change while the female mice experienced a 27.5-percent reduction. The catch, however, is that only the female mice without ovaries experienced notable weight changes, while the female mice that still had ovaries didn't experience the same changes. The researchers say this indicates estrogen's role in weight regulation.

The findings may one day pave the way for a treatment that helps women shed the midsection weight commonly gained during menopause. Assuming the same effects could be translated from mice to humans, the researchers estimate that a 250lb human would lose around 50lbs taking this kind of enzyme inhibitor without any changes in exercise or diet.