A new study from Johns Hopkins Medicine has revealed something surprising: a drug first developed for Alzheimer’s disease, schizophrenia, and sickle cell disease may also help people lose weight and improve heart health — all without dieting or exercising.
The findings bring new hope for treating obesity, one of today’s biggest global health challenges. Obesity increases the risk of heart disease, diabetes, liver problems, and many other conditions. Despite years of research, there is still no simple pill that can safely and effectively treat severe obesity. This new discovery could change that.
The research focused on an enzyme in the body called PDE9. This enzyme helps control a molecule known as cyclic GMP, which affects how cells function and communicate. PDE9 is similar to another enzyme, PDE5, which is the target of the well-known drug Viagra.
Scientists have long studied PDE9 inhibitors for other conditions such as Alzheimer’s and heart failure, but no one had seriously looked at their effects on weight and metabolism — until now.
The study, led by Dr. David Kass and published in the Journal of Clinical Investigation, used mice to test a PDE9-blocking drug developed by Pfizer, known as PF-04447943.
Pfizer originally designed this drug to treat Alzheimer’s disease, but it was later abandoned when it didn’t show strong results for that condition. However, clinical tests in more than 100 people showed the drug was safe, with no major side effects.
The researchers wondered if blocking PDE9 could help with obesity and related health problems such as high blood pressure, high cholesterol, and fatty liver.
When they gave the drug to mice with obesity, the results were remarkable. The mice lost a significant amount of weight, their liver fat decreased, and their heart function improved — all without any change in diet or physical activity.
If the same effects occur in humans, this drug could be a major breakthrough. Researchers estimate that a person weighing 250 pounds might lose around 50 pounds simply by taking the medication. In addition to weight loss, the drug could also lower the risks of heart disease, diabetes, and other conditions linked to obesity.
What makes this discovery even more promising is that it suggests the drug works by improving how the body uses energy, rather than by suppressing appetite. That means it could help people who have struggled with traditional weight-loss methods like calorie restriction or intense exercise.
It might also help prevent long-term complications that come with obesity, including heart failure and fatty liver disease.
In the United States, over 40% of adults are obese, and the rates are even higher in older women. With so many people affected and few effective solutions available, a drug like this could make a life-changing difference.
While the results are early and still limited to animal studies, other PDE9 inhibitors are already being tested in humans for heart conditions. This adds to the growing evidence that this class of drugs could safely improve metabolism and heart health in people.
More research is needed before such a drug could reach the public, but scientists are optimistic. The discovery opens the door to a completely new way of treating obesity — one that could help millions live longer, healthier lives without drastic lifestyle changes.
If you care about Alzheimer’s, please read studies about the likely cause of Alzheimer’s disease, and new non-drug treatment that could help prevent Alzheimer’s.
For more health information, please see recent studies about diet that may help prevent Alzheimer’s, and results showing some dementia cases could be prevented by changing these 12 things.
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