A natural substance found in common herbs such as rosemary and sage could one day help people with Alzheimer’s disease.
Researchers have created a new and more stable version of this plant compound and found that it improved memory and reduced brain damage in animals with Alzheimer’s disease. Although the research is still in its early stages, the results have given scientists hope that a safer and more effective treatment may be possible in the future.
The study was carried out by researchers at Scripps Research and was published in the journal Antioxidants.
Alzheimer’s disease is the most common cause of dementia. Dementia is a group of conditions that affect memory, thinking, language, and the ability to carry out everyday tasks. Alzheimer’s disease slowly damages brain cells over many years, making it harder for people to remember recent events, recognize loved ones, solve problems, and live independently.
Around the world, millions of families are affected by this disease, and the number continues to grow as people live longer.
Scientists have spent decades searching for better treatments. Most currently available medicines can only ease symptoms for a limited time.
They cannot stop the disease from getting worse. Newer drugs that remove harmful proteins from the brain may help some people, but they can also cause serious side effects and do not work for everyone. Because of this, researchers are exploring many different ways to protect the brain.
Rosemary has been linked with memory for hundreds of years. In fact, the famous writer William Shakespeare even referred to rosemary as a symbol of remembrance. Modern scientists have discovered that rosemary and sage contain a natural compound called carnosic acid.
This compound acts as both an antioxidant and an anti-inflammatory. Antioxidants help protect cells from damage caused by harmful molecules, while anti-inflammatory compounds reduce long-lasting inflammation that can injure tissues.
Brain inflammation is now believed to play a major role in Alzheimer’s disease. Long-term inflammation damages brain cells and weakens the tiny connections between them, known as synapses. These connections allow brain cells to communicate with each other and are essential for learning and memory.
Although carnosic acid has shown promise for many years, it has one major problem. It is very unstable. It breaks down quickly when exposed to air or stored for long periods, making it difficult to develop into a medicine.
To solve this problem, the Scripps Research team created a new compound called diAcCA. This new form remains stable during storage but changes back into carnosic acid after it is swallowed. Once it reaches the digestive system, it is converted into the active compound, enters the bloodstream, and travels to the brain.
The researchers tested diAcCA in mice with Alzheimer’s disease. The results were encouraging. The treated mice performed much better on memory tests than untreated mice. Their memory improved so much that it nearly returned to normal levels.
When the scientists examined the animals’ brains, they found several important improvements. There were more healthy synapses connecting brain cells, less inflammation, and lower amounts of two harmful proteins strongly linked to Alzheimer’s disease.
These proteins, called amyloid-beta plaques and phosphorylated tau, are considered key signs of the disease because they build up in the brain and interfere with normal brain function.
The new compound also delivered more of the helpful ingredient to the body. Compared with taking carnosic acid directly, diAcCA allowed about 20 percent more of the active compound to be absorbed. This means more of the medicine reached the brain where it could do its job.
Another encouraging finding was safety. The researchers did not see signs of toxicity in the treated animals. They even found that the compound appeared to reduce normal levels of inflammation in the digestive system, suggesting it may have other health benefits as well.
Lead researcher Dr. Stuart Lipton explained that one of diAcCA’s biggest strengths is that it mainly becomes active in inflamed areas of the brain. This targeted action may help protect damaged brain tissue while leaving healthy tissue largely unaffected, reducing the risk of unwanted side effects.
Because carnosic acid comes from a compound that already has a strong safety record, researchers hope the path toward human clinical trials may be faster than for completely new medicines.
However, much more work is still needed. Results in mice do not always predict what will happen in people. Scientists must carefully test the treatment in human volunteers to make sure it is both safe and effective.
The researchers also believe the compound could eventually be studied for other diseases linked to inflammation, including Parkinson’s disease, type 2 diabetes, and heart disease.
While it is far too early to say that rosemary can prevent or cure Alzheimer’s disease, this research shows how natural substances can inspire new medicines. By combining the benefits of plant compounds with modern drug design, scientists may be opening the door to a new generation of treatments that better protect the aging brain.
If you care about Alzheimer’s, please read studies about Vitamin D deficiency linked to Alzheimer’s, vascular dementia, and Oral cannabis extract may help reduce Alzheimer’s symptoms.
For more information about brain health, please see recent studies about Vitamin B9 deficiency linked to higher dementia risk, and results showing flavonoid-rich foods could improve survival in Parkinson’s disease.
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