Scientists may have found an unexpected new way to fight obesity.
A medicine that was originally developed to treat Alzheimer’s disease could one day help people lose weight and improve their overall health, even without major changes to their diet or exercise habits.
The research comes from Johns Hopkins Medicine and was published in the Journal of Clinical Investigation. Although the work has only been tested in animals so far, the findings suggest that an abandoned drug could be given a completely new purpose.
Obesity is a major health problem around the world. Carrying too much body fat increases the risk of type 2 diabetes, heart disease, fatty liver disease, high blood pressure, and many other serious illnesses. While healthy eating and regular exercise remain the foundation of weight management, many people struggle to lose enough weight or keep it off over the long term.
The researchers focused on a protein called phosphodiesterase 9, or PDE9. Proteins called enzymes help control many chemical reactions inside the body, and PDE9 helps regulate a signaling molecule known as cyclic GMP. This molecule affects how cells communicate and how the body uses energy.
Scientists have studied PDE9 for years because they believed it might be useful for treating conditions such as Alzheimer’s disease, schizophrenia, sickle cell disease, and heart disease.
One drug that blocks PDE9, called PF-04447943, was developed by Pfizer for Alzheimer’s disease, but it did not prove effective enough for that illness. However, earlier clinical testing suggested that the drug was generally safe and caused no major side effects.
In the new study, the researchers gave the drug to mice that had obesity and poor metabolic health. The animals continued eating the same amount of food and were no more active than before. Even so, they lost weight during treatment.
The benefits went beyond weight loss. The mice also showed healthier liver tissue and improved heart function. These findings suggest that blocking PDE9 may help the body burn fat more efficiently while protecting important organs that are often damaged by obesity.
If future human studies produce similar results, this type of medicine could become an important new treatment option. Instead of working mainly by reducing appetite, it may help the body use stored fat more effectively. Researchers believe this could provide another approach for people who have not achieved enough success through lifestyle changes alone.
The scientists caution that these results are still at an early stage. Animal studies do not always predict what will happen in people, so carefully designed clinical trials will be needed before the drug can be approved for obesity treatment. Fortunately, related PDE9-blocking drugs are already being tested for other medical conditions, which may help speed future research.
While much more work remains, the study offers fresh hope that existing medicines can sometimes be repurposed to solve completely different health problems.
If future research confirms these findings, a drug once considered unsuccessful for Alzheimer’s disease could eventually become a valuable tool in treating obesity and reducing the health risks that come with it.
If you care about Alzheimer’s disease, please read studies about vitamin D deficiency linked to Alzheimer’s and dementia, and strawberries can be good defence against Alzheimer’s.
For more health information, please see recent studies about foods that reduce Alzheimer’s risk, and oral cannabis extract may help reduce Alzheimer’s symptoms.
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