Researchers at the ICMR-National Institute of Nutrition (ICMR-NIN), Hyderabad, have found that exposure to lead can significantly disrupt the natural waste-clearing and recycling system of nerve cells, providing fresh insight into how environmental factors may contribute to cellular changes associated with neurodegenerative disorders such as Alzheimer’s disease.

Effects of lead and protein fragments associated with Alzheimer’s disease studied

The study examined the effects of lead and amyloid-beta (Aβ) peptides, protein fragments associated with Alzheimer’s disease, on human neuronal cells in the laboratory. Nerve cells rely on lysosomes, tiny structures within cells that act as a waste-disposal and recycling system. They break down damaged proteins and other unwanted cellular material, helping maintain cellular health and function.

Impact on structures that act as a waste-disposal and recycling system

The researchers found that exposure to either lead or amyloid-beta peptides individually impaired lysosomal function. However, combined exposure caused significantly greater disruption as it reduced cell survival, disturbed the acidic environment required for normal lysosomal function and damaged lysosomal structure.

In addition, lysosomal membranes became unstable and leaky, potentially allowing harmful enzymes to escape into the cell and cause further damage. According to the researchers, these findings suggest that environmental lead exposure may amplify the cellular stress associated with amyloid-beta and make nerve cells more vulnerable to injury.

ICMR-NIN’s Head of Cell Biology Suresh Challa, who led the research team, said, “Understanding these cellular changes can help us better understand how environmental exposures may influence neuronal health.” “The study highlights the importance of understanding the interaction between environmental pollutants and biological factors in maintaining brain health,” said ICMR-NIN director Bharati Kulkarni, according to a press release.