8. How studying microRNA can detect Alzheimer’s early
MicroRNA 142 [Image from Indiana University]
The researchers found that the changes in microRNA were able to be detected in mice before they started to show symptoms of neurodegeneration. The changes could be an early sign or a biomarker for the condition.
“Identifying biomarkers early in a disease is important for diagnosing the condition, and following its progression and response to treatment,” Hui-Chen Lu, who led the study, said in a press release. “You need something that can predict your future.”
MicroRNA acts as regulators, unlike messenger RNA which directs cells to produce specific proteins. MicroRNA increases or decreases the number of proteins that messenger RNAs encode. A single microRNA can affect the functions of hundreds of proteins in the body.
Lu and her team analyzed microRNA and messenger RNA in a healthy group and a group of genetically modified to develop symptoms of dementia. The research team saw the highest levels of deviation from normal levels in microRNA of the denentia group before the mice developed physical symptoms.
“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,” Lu said.
The research team then compared microRNA changes to messenger RNA changes to figure out the biological pathways that are affected by microRNA dysregulation. They suggested that the changes in microRNA affected pathways that were related to immunity in a dementia-prone model. So, the team conducted more tests to study a microRNA called microRNA 142 that is elevated in dementia models and plays a role in inflammation.
When introducing microRNA 142 to the brain, there was significant neuroinflammation. The researchers suggest that this result is important because it shows that chronic inflammation can cause different types of diseases, including neurodegeneration.
