A research team, including an Indian-origin boffin, has made a new discovery that could lead to a new treatment for Alzheimer's disease.
The discovery by researchers from the Mayo Clinic in Jacksonville, FL is based on the unexpected finding that when the brain's immune cells (microglia) are activated by the interleukin-6 protein (IL-6), they actually remove amyloid plaques-considered a hallmark of the disease, instead of causing them or making them worse.
The study was conducted in a model of Alzheimer's disease established in mice.
"Our study highlights the notion that manipulating the brain's immune response could be translated into clinically tolerated regimens for the treatment of neurodegenerative diseases," said Pritam Das, co-author of the study, from the Mayo Clinic in Jacksonville, FL.
Das and colleagues made this unexpected discovery when they initially set out to prove that the activation of microgila trigger inflammation, making the disease worse.
Their hypothesis was that microglia would attempt to remove the plaques, but would be unable to do so, and in the process cause excessive inflammation.
The researchers were surprised to find that when microglia were activated by IL-6, they cleared the plaques from the brains.
To do this, the researchers over-expressed IL-6 in the brains of newborn mice that had yet to develop any amyloid plaques, as well in mice with pre-existing plaques.
Using somatic brain transgenesis technology, scientists analyzed the effect of IL-6 on brain neuro-inflammation and plaque deposition. In both groups of mice, the presence of IL-6 lead to the clearance of amyloid plaques from the brain.
The researchers then set out to determine exactly how IL-6 worked to clear the plaques and discovered that the inflammation induced by IL-6 directed the microglia to express proteins that removed the plaques.
This study suggests that manipulating the brain's own immune cells through inflammatory mediators could lead to new therapeutic approaches for the treatment of neurodegenerative diseases, particularly Alzheimer's disease.
The study has been published online in The FASEB Journal.