Health experts have pointed out how smoking increases the risk of dementia, a condition involving cognitive decline and memory loss, stating that the reason is that the lungs are directly connected to the brain.
In this regard, a recent study conducted at the University of Chicago in the United States suggests that nicotine can activate a new biological pathway that helps explain this connection.
Previous research had shown that people who smoke heavily in middle age have more than double the risk of developing dementia, including Alzheimer’s disease, decades later.
During the study, scientists discovered that specific lung cells, known as pulmonary neuroendocrine cells, release very small particles called exosomes in response to nicotine. These interfere with the process that controls iron balance in the brain, which is essential for healthy nerve cells.
As a result, disruption in iron balance can damage neurons, put stress on their energy systems, and trigger processes associated with neurodegenerative diseases such as Alzheimer’s and Parkinson’s.
According to co author of the research team and postdoctoral researcher Kui Zhang, this study establishes a clear lung brain connection, which may explain why smoking is linked to mental decline.
The study, published in the medical journal Science Advances, was based on laboratory models and PNECs developed from stem cells. Although the findings are promising, researchers have cautioned that further studies are needed to confirm this mechanism in humans.
