Most news in recent years about research into Alzheimer’s disease - the ultimately-fatal, neurodegenerative disease which accounts for the majority of cases of dementia, and affects more than 500,000 people in the UK alone - has focused on astronomically-expensive yet invariably-failed clinical trials. Articles lamented a lack of funding, a lack of volunteers, a lack of genuine motivation to find a cure or a treatment for the disease, and a lack of innovative research directions; they spoke of dead ends, stalemates, and research into the disease having all but stalled. The picture was deeply gloomy.

Well, for once there’s a bit of good news: scientists from Duke University have just uncovered a new and unexpected explanation for the development of the disease. Their recent study suggests that immune cells that normally protect the brain could be "going rogue” and beginning abnormally to consume an important nutrient called arginine. (Arginine is an amino acid known to be crucial for things like cell division, healing, and immune responses; however, this discovery suggests a hitherto-unknown role for arginine.) Moreover, the team was able to use an existing cancer drug to block this process in the brains of mice, preventing further formation of the brain plaques associated with Alzheimer’s disease, and halting memory loss in the mice.

This new research contradicts conventional wisdom in clinical trials involving the disease, which traditionally have focused on slowing the accumulation of plaques. But the new research suggests that by the time the plaques are visible, irreparable damage has likely already been done. Therefore a shift away from the focus on a consequence of the disease (plaques), and towards improving our understanding the mechanism of the disease itself, might be advocated.

Of course, mice brains are not necessarily very good analogues for human brains, and so it remains to be seen how these findings might translate to humans. Nevertheless - it is hugely encouraging to think the scientists might be on the brink of understanding much more about one of the most complex, costly and destructive diseases with which humanity finds itself (increasingly) confronted.