Researchers have found evidence that long COVID may involve damage to dopamine-releasing neurons, potentially explaining persistent fatigue, memory issues, and motivation loss.
Key facts
- •Long COVID is estimated to affect approximately five percent of the global population, including about two million people in Canada.
- •The study utilized PET imaging to measure biological activity and dopamine neuron health markers in the brain.
- •Previous research by the same team identified high levels of brain inflammation in regions containing dopamine-releasing neurons.
- •Researchers plan to begin a clinical trial in the coming months to evaluate if targeting dopamine function can alleviate long COVID symptoms.
- •The study was supported by the Canadian Institutes of Health Research.
A study led by the Centre for Addiction and Mental Health (CAMH) has identified evidence of damage to dopamine-releasing neurons in patients with long COVID. Published in eBioMedicine, the findings suggest this neurological injury may be responsible for common symptoms such as fatigue, brain fog, and memory difficulties. Researchers used positron emission tomography (PET) to compare brain activity in long COVID patients against healthy participants.
Neurological Findings and Symptom Correlation
The study revealed significantly lower levels of a marker for dopamine neuron health across all major areas of the striatum, a brain region responsible for regulating motivation, movement, and cognition. Lower marker levels indicate a reduced density of dopamine nerve terminals. Researchers identified specific correlations between regional neuron loss and patient symptoms. Reduced levels in the ventral striatum were linked to loss of motivation, while reductions in the dorsal putamen were associated with slower movement. Memory difficulties were connected to lower levels in the caudate putamen.
Connection to Brain Inflammation
These results build upon previous research by the same team, which observed unusually high levels of brain inflammation in long COVID patients, particularly in regions rich in dopamine-releasing neurons. Dr. Jeffrey Meyer, the study's senior author, noted that inflammation is known to injure these neurons. The current findings provide direct evidence that the dopamine neuron marker is reduced in those same inflamed areas, suggesting a link between persistent inflammation and damage to the dopamine system.
Future Clinical Trials and Treatment Potential
The research team suggests that long COVID may be, in part, a disorder of the dopamine system. This perspective could shift treatment strategies toward medications that augment dopamine-releasing neuron function, such as dopamine precursors or inhibitors of dopamine metabolism. The team plans to launch a clinical trial in collaboration with the University Health Network within the next few months to test whether modifying dopamine activity can improve patient symptoms.
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This article was independently rewritten by ManyPress editorial AI from reporting originally published by ScienceDaily.
