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New Delhi, March 1 (IANS) Toxins found in air pollution, and wildfire smoke may trigger a chemical change in the brain that can lead to memory loss as seen in Alzheimer’s disease, according to a study.
Scientists at Scripps Research, US, discovered a chemical change — known as S-nitrosylation — that prevents brain cells from making new connections and ultimately results in cellular death.
Blocking S-nitrosylation partially reversed signs of memory loss in Alzheimer’s mouse models and nerve cells produced from human stem cells.
“We’ve revealed the molecular details of how pollutants can contribute to memory loss and neurodegenerative disease,” said Stuart Lipton, Professor at Scripps Research.
“This could ultimately lead to new drugs that block these effects to better treat Alzheimer’s disease,” Lipton added.
The findings are published in the journal Proceedings of the National Academy of Sciences. Lipton’s research group and colleagues have previously demonstrated that aberrant S-nitrosylation reactions contribute to some forms of cancer, autism, Alzheimer’s disease, Parkinson’s disease, and other conditions.
In the new study, Lipton and team investigated the effect of S-nitrosylation on the protein CRTC1, which helps regulate genes that are critical for forming and maintaining connections between brain cells.
Using cultured brain cells from mice and humans, the researchers first confirmed that excess nitric oxide (NO) leads to S-nitrosylation of CRTC1. They then discovered that this chemical modification prevented CRTC1 from binding to another critical brain regulatory protein, CREB.
As a result, other genes necessary for forming connections between neurons failed to be stimulated.
“This is a pathway that affects your memory and is directly implicated in human Alzheimer’s disease,” said Lipton.
In both the Alzheimer’s mouse model and in human neurons derived from stem cells of patients with the neurodegenerative condition, the team observed high levels of S-nitrosylated CRTC1 at an early stage of the disease.
The findings further support the idea that chemical change plays a key role in the development of disease symptoms.
–IANS
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