Lead exposure may worsen Alzheimer's-linked neuronal damage: ICMR-NIN study

A new study by scientists at the ICMR-National Institute of Nutrition (ICMR-NIN) in Hyderabad has revealed that environmental lead exposure can significantly impair the natural waste-disposal and recycling machinery of nerve cells. This disruption may make neurons more vulnerable to damage associated with neurodegenerative conditions like Alzheimer's disease.

The research, led by Suresh Challa, Head of Cell Biology at ICMR-NIN, examined how lead and amyloid-beta (Aβ) peptides—protein fragments linked to Alzheimer's—affect human neuronal cells in laboratory settings. Nerve cells depend on lysosomes, tiny organelles that act as cellular cleanup crews, breaking down damaged proteins and other debris to maintain health.

The team found that exposure to either lead or amyloid-beta alone impaired lysosomal function. However, when combined, the two agents caused significantly greater harm: cell survival dropped, the acidic environment essential for lysosomal activity was disturbed, and lysosomal structure was damaged. Additionally, lysosomal membranes became unstable and leaky, potentially allowing harmful enzymes to escape and inflict further cellular injury.

These findings suggest that lead exposure could amplify the cellular stress induced by amyloid-beta, increasing the vulnerability of neurons to damage. "Understanding these cellular changes can help us better understand how environmental exposures may influence neuronal health," said Challa. Bharati Kulkarni, Director of ICMR-NIN, added, "The study highlights the importance of understanding the interaction between environmental pollutants and biological factors in maintaining brain health."

The study underscores the potential role of environmental pollutants in the progression of neurodegenerative diseases and calls for greater attention to reducing lead exposure as a public health measure.