Connecting two culprits in Alzheimer’s disease

Plaques and tangles pockmark the brains of people with Alzheimer’s disease. The extracellular protein amyloid-β makes plaques, and the intracellular protein tau makes tangles, but how exactly these might kill neurons is unclear. Work presented at the annual meeting of the American Society for Cell Biology in San Francisco, California, this week starts to connect some of these dots.

George Bloom, of the University of Virginia in Charlottesville, and his colleagues began by following up on work that neurons exposed to amyloid-β die not from direct poisoning, but because amyloid-β prompts inappropriate cell behaviour. They re-enter the cell cycle but never divide, and die instead.

“The framework of the process has now been defined,” he says. “We think we’ve stumbled upon one of the seminal events in the transition of healthy neurons into Alzheimer neurons.”

The work identifies several potential very early biomarkers of Alzheimer’s disease and suggests new ideas to treat it. Continue reading

Alzheimer’s rage

It’s nice to be hear from diaspora Indian scientists about the wonderful work they have been doing in foreign labs. Nature India features some such exceptional work in its news and features section once a while.

Itender Singh{credit}URMC{/credit}

This week we heard from Itender Singh, a Delhi University alumnus and presently a research assistant professor at the University of Rochester Medical Center in USA. His work with colleagues from the centre  and elsewhere has resulted in development of a new compound that promises to work wonders for people with Alzheimer’s disease (AD). Their success story (and paper published in the Journal of Clinical Investigation) is already getting a lot of peer attention[1], [2], [3].

Singh and colleagues have created a new compound that acts to inhibit the functioning of another compound called RAGE, which is known to play a key role in the accumulation of beta amyloid levels in the brain of people with AD. Such accumulation of beta amyloids is known to be the the main trigger for neuronal loss and dementia. So, in essence, the researchers have found a compound that cuts out the nuisance value of RAGE.

Earlier therapies to reduce the production or aggregation of beta amyloids have not worked out to be effective. Singh and colleagues have created a novel ‘small-molecule inhibitor’ which works in this manner — it blocks the functioning of RAGE (acronym for ‘Receptor for Advanced Glycation End products’) thus helping reverse the beta amyloid levels in the brain.

Their work on aged mice has shown that this small molecule inhibitor can normalize cognitive performance. This looks like one of the most promising anti-RAGE therapies till date.

Though the scientists warn that it’s still a long way to go when people with AD can actually reap the benefits of their research, we hope the therapy gets through the necessary trials soon and leaps from the bench to the bedside at the earliest to provide relief to the suffering elderly.