London: British scientists claim to have beat a key problem in treating dementia and motor neurone disease, by discovering a novel way to get medicines into the brain to treat the common memory disorders.

A team at Oxford University says the breakthrough may pave the way for a new generation of treatments for conditions such as Alzheimer's, Parkinson's, motor neurone disease and
muscular dystrophy, a journal reported.

Until now, it has been extremely tough to get drugs into the brain because of an efficient filter known as blood- brain barrier.

But, now the British scientists have discovered how to hide medicines from this filter by attaching them to tiny molecules, released by cells, called exosomes. They can send drugs into brain to switch off a gene linked to Alzheimer's.

However they believe it may be a few more years before the technique is safe enough to test on humans.

Dr Matthew Wood, who led the study, was quoted by a newspaper as saying, "These are dramatic and exciting results. It's the first time new biological medicines have been delivered effectively across the blood-brain barrier to the brain."

Exosomes are small capsules that are produced by most cells in the body. They can break away from the cell and travel around the body, taking genetic material with them.

They help cells to "talk" to each other. Dr Wood added: "We've shown that a natural system
could be exploited to deliver drugs. We believe we can use this same technology for  Alzheimer's, motor neurone disease, Parkinson’s and Huntington's.

"The next steps are to test the exosomes in a mouse model of Alzheimer's disease to see if it makes a difference to disease progression."

The trial showed that when the drug was attached to exosomes and injected into the blood system of mice, it crossed the blood-brain barrier and ended up in the brain.

The Alzheimer's Society has hailed the discovery.