Scientists at Johns Hopkins Medicine have discovered something surprising that could lead to new treatments for Alzheimer’s disease.
A recent study found that a special protein in the brain, known as Cystathionine γ-lyase or CSE, may help protect memory and brain health.
This protein produces a gas called hydrogen sulfide, which smells like rotten eggs. Even though the gas smells bad and can be dangerous in large amounts, in very tiny amounts it plays an important role in brain function.
The new research shows that when this protein is missing in mice, they develop problems with memory, learning, and brain health—similar to symptoms seen in people with Alzheimer’s disease. These findings suggest that the CSE protein may help prevent or slow down brain diseases like Alzheimer’s.
During a heart attack, brain cells can be damaged by stress and lack of oxygen. Scientists already knew that hydrogen sulfide can protect brain cells in mice. But because it’s harmful in large amounts, researchers are working to understand how the brain naturally keeps the right tiny amount of this gas to stay healthy.
In the study, scientists used mice that were genetically changed so they didn’t have the CSE protein. These mice had trouble with memory tasks and showed signs of brain damage such as stress on cells, DNA damage, and problems with the blood vessels in the brain. All these are common signs seen in Alzheimer’s disease.
Back in 2014, researchers found that CSE was helpful for brain health in mice with another brain disease called Huntington’s disease.
Later, in 2021, they saw that mice with Alzheimer’s had problems with their CSE protein and that tiny amounts of hydrogen sulfide helped protect their brains. But those older studies looked at mice with other genetic changes. This new research focuses only on the CSE protein itself.
The scientists ran memory tests on the mice using a tool called the Barnes maze. The test checks whether mice can find shelter after being shown a bright light. At two months old, both normal mice and those without CSE could complete the task.
But by six months, the CSE-lacking mice could no longer find the escape, while the normal mice still could. This showed that the mice without the CSE protein were slowly losing their memory.
The team also studied a part of the brain called the hippocampus, which is very important for memory. They found that in mice missing CSE, the brain was not able to make new brain cells properly. Even the new brain cells that were made had trouble moving to the right part of the brain to help with memory.
When researchers looked closely at the brain tissue using powerful microscopes, they saw broken blood vessels in the mice without CSE. This damage to the brain’s blood supply is another warning sign of Alzheimer’s disease.
These findings are very important. Over six million people in the U.S. are living with Alzheimer’s, and that number is going up. Right now, there’s no cure and very few treatments that work well.
This study gives scientists a new idea—maybe boosting the CSE protein or safely increasing hydrogen sulfide levels in the brain could help treat or slow down Alzheimer’s disease. More research is needed, but this could be a big step forward in finding new ways to protect brain health.
If you care about Alzheimer’s disease, please read studies that bad lifestyle habits can cause Alzheimer’s disease, and strawberries can be good defence against Alzheimer’s.
For more information about brain health, please see recent studies that oral cannabis extract may help reduce Alzheimer’s symptoms, and Vitamin E may help prevent Parkinson’s disease.
The study is published in the Journal of Neuroinflammation.
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