June 29 (UPI) -- There is currently no treatment to stop or reverse the effects of neurodegenerative diseases such as Alzheimer's, Parkinson's, ALS or Huntington's. But new research has found that tiny snippets of genetic material called microRNA can help detect the diseases early.
"Identifying biomarkers early in a disease is important for diagnosing the condition and following its progression and response to treatment," Hui-Chen Lu, a professor in the Linda and Jack Gill Center for Biomolecular Science and the Department of Psychological and Brain Sciences at Indiana University, said in a press release. "You need something that can predict your future."
Hui-Chen led the study, published this month in Nature Scientific Reports, that found changes in microRNA are detectable in mice long before they start to show symptoms of neurodegenerative conditions.
These changes may serve as an early warning sign, or "biomarker," for the condition, researchers said.
It is estimated that Alzheimer's disease, which is the most common of the neurodegenerative disorders, will affect 14 million Americans and cost taxpayers $1.1 trillion by 2050.
Researchers analyzed microRNA and messenger RNA in two groups of rats: healthy ones, and a group genetically modified to develop symptoms of dementia. They found the highest level of "dysregulation," or deviation from normal levels, in the microRNA of the dementia group before their physical symptoms developed.
"Higher levels of pre-symptomatic microRNA dysregulation are significant because it strongly suggests that it may have a role in changes in the brain in later stages," Hui-Chen said.
MicroRNA is a better predictor of the diseases than regular "messenger RNA," which directs cells to produce specific proteins. MicroRNA plays a regulatory role, increasing or decreasing the number of proteins that messenger RNAs encode. A single snippet of microRNA can impact the function of tens or hundreds of proteins in the body.
MicroRNA show up in urine and blood, so it provides a good method for scientists to use it as biomarkers for disease prediction and diagnosis. The study is an early step to learn whether microRNA can be used to detect neurodegenerative disorders.
The team compared the microRNA changes to the messenger RNA changes to identify biological pathways affected by microRNA dysregulation. Their analysis suggested that changes in microRNA affected pathways related to immunity in the dementia-prone model.
The team then conducted additional tests to study a specific type of microRNA that they noticed more of in the dementia model. That type, microRNA 142, is known to play a major role in inflammation, a part of the immune response.
They found that introducing this microRNA into the brain triggered a significant neuroinflammation. This is significant because many other studies have shown that chronic inflammation contributes to many types of disease, including neurodegeneration.