Alzheimer’s disease is the most common cause of dementia and affects millions of people around the world. It is a progressive brain disease, which means it slowly gets worse over time.
At first, a person may simply forget recent conversations or misplace everyday items.
As the disease advances, it can affect thinking, decision-making, language, and the ability to carry out daily activities. Eventually, many people need full-time care.
Scientists have spent many years trying to understand what causes Alzheimer’s and how to detect it before serious damage occurs.
One of the biggest challenges is that harmful changes in the brain often begin many years before memory problems become obvious.
By the time symptoms appear, many brain cells have already been damaged.
Finding a simple way to identify people at risk earlier could give doctors more time to start treatment and help patients plan for the future.
A new study from the University of California San Diego has brought researchers one step closer to that goal. The research, led by Professor Sheng Zhong and published in the journal Cell Metabolism, found that high levels of an enzyme called PHGDH may serve as an early warning sign of Alzheimer’s disease.
PHGDH is a natural enzyme made by the body. Its job is to help produce an amino acid called serine. Amino acids are small building blocks that the body uses to make proteins, and serine plays an important role in many normal brain functions. Under healthy conditions, the amount of PHGDH is carefully controlled.
The researchers discovered that people with Alzheimer’s had much higher levels of PHGDH in their brains than healthy people. Even more importantly, increased PHGDH was found in some people before they showed clear signs of memory loss. This suggests that the enzyme may become abnormal very early in the disease process.
To investigate further, the team studied genetic information from brain tissue donated by people aged 50 years and older. The samples came from four separate research groups and included healthy adults, people with early brain changes linked to Alzheimer’s, and people who had already developed the disease.
The results were remarkably consistent. In every group, people with Alzheimer’s had much higher PHGDH levels than healthy participants. The researchers also found that people with the highest PHGDH levels usually performed worse on memory and thinking tests. This strong relationship suggests that the enzyme is closely linked with disease progression.
The scientists then looked at specially bred mice that develop changes similar to Alzheimer’s disease. The mice also showed increased PHGDH levels, providing further evidence that the enzyme is involved in the disease rather than being an accidental finding.
One unexpected discovery involved serine supplements. Some people take serine because it has been promoted as a supplement that may support brain health. However, since PHGDH helps make serine, researchers now believe people with Alzheimer’s may already be producing too much through this pathway.
This raises concerns that taking extra serine supplements could potentially be unhelpful or even harmful for people at risk of Alzheimer’s. The researchers stress that more studies are needed before firm conclusions can be made, but they recommend caution until scientists better understand the effects.
Perhaps the most exciting part of the study is the possibility of developing a simple blood test that measures PHGDH. If future studies confirm these findings, doctors may eventually be able to identify people who are developing Alzheimer’s many years before symptoms appear. Earlier diagnosis could allow patients to begin treatments sooner, join clinical trials, and make lifestyle changes that may help protect brain health.
Although there is still no cure for Alzheimer’s disease, research suggests that healthy habits may lower the risk or delay its onset. Regular exercise improves blood flow to the brain. A Mediterranean-style diet rich in vegetables, fruit, whole grains, fish, olive oil, beans, and nuts has been linked with better brain health.
Keeping the mind active by reading, learning new skills, solving puzzles, and staying socially connected may also help maintain healthy brain function. Managing conditions such as high blood pressure, diabetes, obesity, and high cholesterol is also important because they can affect the health of blood vessels that supply the brain.
This study represents an important advance in Alzheimer’s research. While more work is needed before PHGDH testing becomes part of routine medical care, the findings suggest that this enzyme could become a valuable biomarker for detecting the disease earlier than ever before.
Earlier diagnosis could give patients, families, and doctors precious time to prepare and may improve the chances of slowing the disease in the future.
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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