Sensorimotor Cortex Reorganization in Alzheimer's Disease and Metal Dysfunction: A MEG Study

Area of Science:

• Neuroscience
• Biometals Research
• Alzheimer's Disease Pathophysiology

Background:

• Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive cognitive decline.
• Systemic biometal dysfunctions, particularly copper imbalances, are implicated in AD pathogenesis.
• The precise role of specific copper fractions in AD-related neurotransmission deficits remains unclear.

Purpose of the Study:

• To investigate the association between systemic biometal levels and neurotransmission in living Alzheimer's disease patients.
• To assess the neuroplasticity of the primary somatosensory cortex in response to disease progression.
• To determine if specific copper fractions, rather than total copper, correlate with altered sensorimotor processing in AD.

Main Methods:

• A case-control study utilizing magnetoencephalography (MEG) to analyze sensorimotor fields in AD patients and controls.
• Assessment of neuronal activation patterns in the primary somatosensory cortex during median nerve stimulation.
• Quantification of systemic levels of copper, ceruloplasmin, non-ceruloplasmin (non-Cp) copper, peroxides, transferrin, and total antioxidant capacity.

Main Results:

• AD patients exhibited spatially shifted sensorimotor generators without changes in latency or strength.
• Greater neuronal reorganization was observed in moderately ill AD patients, while severe AD patients showed increased delta activity.
• Systemic non-Cp copper levels were significantly associated with sensorimotor transmission alterations in AD patients.

Conclusions:

• Non-ceruloplasmin copper, specifically, influences neuronal activity and sensorimotor transmission in Alzheimer's disease.
• The findings suggest that early-stage AD exhibits significant neuroplasticity, potentially influenced by environmental factors.
• Physical and cognitive activities may serve as protective factors against AD progression due to their potential to enhance neuroplasticity.