Scientists in the US claim to have developed a compound that makes neurons grow, which could lead to treatments for people with dementia.
Researchers at the University of Texas Southwestern injected 1,000 different chemicals into the brains of live mice, making the resulting discovery due to "blind luck", according to study leader Steven McKnight.
Once they identified the potential of P7C3, they injected it into live, ageing rats.
It was then found that this chemical did help the brain to make new neurons that are fully functional - a discovery which could be the key to making new drug treatments for dementia.
Reacting to the study, the chief executive of the Alzheimer's Research Trust Rebecca Wood said that any research that seeks to address the "fundamental destructive force" of dementia is worth taking seriously.
She added: "This preliminary study, while only in rats, suggests that a protective drug for brain cells could one day be achievable.
"Steps must now be taken to research whether the compound can be used beneficially and safely in people."
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