Alzheimer's disease could be caused by a single type of protein in the human body going haywire, researchers in Singapore have found.
They discovered the protein indirectly controls new brain cells' growth and maturity, which are essential to keeping the brain healthy.
The team hopes to build on the discovery and create, within five years, a non-invasive way to detect the onset of dementia, referring generally to brain disease that involves the loss of cognitive abilities and includes Alzheimer's.
The research was led by the National Neuroscience Institute (NNI), a unit of public health-care group SingHealth.
It also involved the Agency for Science, Technology and Research (A*Star) and Duke-NUS Graduate Medical School.
The findings were published last month in the prestigious science journal, Nature Communications.
The researchers already knew from previous studies that the protein, called the amyloid precursor protein (APP), is a main culprit of Alzheimer's, although how it causes the disease exactly is unknown.
The latest study, led by research scientist Zeng Li and her NNI team showed a molecule called microRNA-574-5p is involved in creating neurons in the brain.
The Singapore scientists also compared two groups of mice to better understand APP's link to neurodegenerative diseases. The mice in one group had their APP removed and the other group was the control.
One finding leaped out: The APP-deficient mice had much higher levels of the microRNA-574-5p molecule.
Their study could point to how APP is linked to Alzheimer's: problems with the protein could lead to abnormal levels of the molecule, affecting neurons' creation and eventually leading to the disease.
"Our findings highlight that microRNA-574-5p may be a useful new target for drug development against Alzheimer's," said NNI's Dr Zeng. However, much more work needs to be done, she added.
To further clarify the link between the protein, molecule and neurodegenerative diseases such as Alzheimer's and Parkinson's, the team intends to study post-mortem brain samples from patients. It also wants to look at other microRNAs that could play a role in the neurological diseases.
Abnormalities in some of these molecules are "implicated in other devastating psychiatric disorders like autism and schizophrenia", said Duke-NUS Assistant Professor Shawn Je.
Added A*Star's Professor Stephen Cohen, a renowned expert in microRNA biology: "We are at an early stage of understanding how this microRNA might impact disease progression... but the prospects are exciting."
Some 80,000 people in Singapore aged 60 and above are expected to have dementia in 2030, up from 28,000 now.
This article was published on April 19 in The Straits Times.Get a copy of The Straits Times or go to straitstimes.com for more stories.