Ramping up the brain's garbage disposal system could open up a completely new way of treating Alzheimer's and other neurodegenerative diseases, scientists believe.
Tests on the brains of dead Alzheimer's and Parkinson's disease patients flagged up an abnormality that interferes with autophagy, the natural clearing out and re-cycling of unwanted toxic proteins.
An experimental molecule was able to undo this defect in mice modelling both diseases, allowing their nerve cells to rid themselves of the toxins.
Scientists hope the early research could lead to new drug treatments that prevent brain damage from harmful accumulating "rubbish".
The approach involves switching off certain receptor cell proteins that prevent autophagy when they become too active.
Lead scientist Dr Charbel Moussa, from Georgetown University Medical Centre in the US, said: "Activation of these cell receptors appears to prevent brain cells from cleaning out the trash - the toxic build-up of proteins ... common in neurodegenerative diseases."
Two of the toxic proteins allowed to pile up when the disposal system stops working are beta-amyloid and tau, both closely linked to Alzheimer's.
It is the first time scientists have been able to demonstrate that "discoidin domain receptors" (DDRs) play a role in Alzheimer's, Parkinson's and possibly other neurodegenerative diseases. They have already been implicated in the progression of cancer.
In their experiments the scientists suppressed the receptors with a low dose of their molecule, code-named LCB-03-110. Targeting the receptors both allowed toxic proteins to be cleared from the brain, and provided protection against inflammation.
"This led to cognitive improvement in our animal models," said Dr Moussa, whose findings were presented at the Alzheimer's Association International Conference in London.
Georgetown University has filed a patent application relating to the use of certain DDR inhibitors for the treatment of neurological diseases.