Overactivation of Brain Cells May Lead to Degeneration in Parkinson's Disease

Recent research by scientists at the Gladstone Institutes suggests that prolonged overactivation of specific brain cells may cause their degeneration, a process linked to Parkinson's disease. These cells, responsible for controlling smooth and coordinated movements, can become overactive due to various factors, leading to their eventual decline and death.

Parkinson's disease, affecting over 8 million people worldwide, is characterized by symptoms such as tremors, slowed movements, muscle stiffness, and balance issues. It is known that dopamine-producing neurons in the brain deteriorate as the disease progresses. Interestingly, evidence shows these neurons' activity increases before and after degeneration, raising questions about whether this heightened activity contributes to cell death.

The study involved genetically modifying mice to allow chronic activation of dopamine neurons through a drug administered in drinking water. This sustained overactivation caused disturbances in the animals' activity cycles within days and initiated degeneration of neuronal projections after a week, with neuron death occurring by the end of a month. Notably, the damage mainly affected neurons in the substantia nigra, the area associated with movement control, mimicking the cellular pattern observed in Parkinson's patients.

Further analysis revealed that overactivation altered calcium levels and gene expression related to dopamine metabolism in these neurons. The neurons appeared to attempt reducing dopamine production to counteract excessive activity, but over time, this led to their demise. Similar gene expression changes were observed in early-stage Parkinson's patients, strengthening the connection between overactivity and neural degeneration.

The researchers hypothesize that genetic, environmental, or compensatory factors may trigger early overactivation in Parkinson's, creating a vicious cycle of neuron stress and death. This understanding opens potential avenues for therapeutic intervention, such as adjusting neuronal activity with drugs or deep brain stimulation, to protect vulnerable cells and slow disease progression.

This study provides valuable insights into the mechanisms behind neuron loss in Parkinson's disease and highlights the importance of regulating neuronal activity for therapeutic strategies.

Source: https://medicalxpress.com/news/2025-08-overworked-brain-cells-parkinson-disease.html