A recent study investigated the potential link between certain amino acids and increased risk of dementia associated with exposure to PM2.5 air pollution. Although not conclusive, this study suggests that high homocysteine or low methionine levels may interact with pollution to increase dementia risk, and may shed light on the mechanisms behind the effects of air pollution on the brain. It emphasizes the need for a deeper understanding.
increase in level amino acid B vitamins may be associated with the risk of dementia associated with certain types of air pollutants known as particulate matter, according to a recently published study. neurology, Medical Journal of the American Academy of Neurology. Although this study does not establish a causal relationship between pollution or amino acids and dementia, it does indicate a potential link between them.
Researchers looked at fine particulate matter, PM2.5, consisting of airborne pollution particles less than 2.5 microns in diameter. They also focused on his two amino acids: methionine and homocysteine.Methionine is an essential amino acid acid It is found in foods such as meat, fish, dairy products, beans, and eggs, and is involved in normal brain function. Homocysteine is an amino acid produced within cells and converted to methionine through a reaction that requires both vitamin B12 and folic acid, nutrients important for red blood cell formation and healthy cell growth and function.
“Previous studies have found a link between air pollution and dementia risk, but the mechanisms by which air pollution affects the brain are not fully understood,” said study author Karolinska Institutet. said Julia Grande, MD. Stockholm, Sweden. “This study found that two B vitamin-related amino acids play a role in increasing or decreasing the risk of dementia caused by air pollution.”
The study followed more than 2,500 adults living in central Stockholm, with an average age of 73, for up to 12 years. Of these, 376 developed dementia.
In addition to interviews and blood tests, participants completed questionnaires about their physical activity and dietary habits.
The researchers then calculated the annual average level of PM.2.5 located at the participant’s home address.People who developed dementia had average exposure to PM2.5 8.4 micrograms per cubic meter (μg/m) of pollution3), compared to 8.3 µg/m3 For those who did not develop dementia. The annual average level of these PMs is2.5 Low compared to the average level of PM2.5 In other parts of Europe it is 13.8 μg/m3.
After adjusting for several factors that influence dementia risk, including age, gender, smoking, and education, the researchers found that the risk of dementia increased by 70% for every 1 μg/m3 .3 Increase in PM2.5 Exposure during the 5 years prior to the start of the study.
The researchers then investigated whether the effect of exposure to air pollution on dementia was influenced by amino acids.
Overall, the researchers found that about half of the increased risk of dementia was due to PM.2.5 The cause was due to the interaction between air pollution and high homocysteine levels or low methionine levels.
“Our findings showed that elevated homocysteine levels and low methionine levels play a role in determining the dementia risk associated with air pollution, but at the same time air pollution is associated with dementia. “We also show that there is a substantial direct effect on the development of dementia, suggesting that air pollution influences the development of dementia through multiple factors,” Grande said. . “This highlights the need for further research into the precise biological mechanisms behind air pollution-induced brain damage.”
Reference: “The association of long-term exposure to air pollution and dementia risk – the role of homocysteine, methionine and cardiovascular load” Julia Grande, Babak Houshmand, Davide Liborio Vetrano, David A. Smith, Helga Refsum, Laura Fratiglioni, Petter Jungmann, Jing Wu, Andrea Bellavia, Cristina Eneros, Tom Belander, Deborah Rizzuto, July 13, 2023. neurology.
DOI: 10.1212/WNL.0000000000207656
A limitation of this study was that it only covered the small Kungsholmen district of Stockholm, which limited comparisons regarding air pollutants.
The study was funded by the Swedish Ministry of Health and Social Affairs, the Swedish Research Council, the Swedish Health, Working Life and Welfare Research Council, and several Swedish foundations.
