Central and Peripheral Inflammation in Mild Cognitive Impairment in the Context of Alzheimer's Disease

Area of Science:

• Neuroscience
• Immunology
• Biochemistry

Background:

• Mild cognitive impairment (MCI) is a precursor to Alzheimer's disease (AD), characterized by cognitive decline.
• Neuroinflammation is increasingly recognized as a key factor in the progression of MCI to AD.
• Identifying early inflammatory mechanisms is crucial for developing diagnostic and therapeutic strategies.

Purpose of the Study:

• To investigate inflammatory biomarker profiles in the central nervous system (CNS) and serum of individuals with MCI.
• To compare biomarker concentrations between MCI patients, non-impaired controls (NIC), and healthy controls (HC).
• To analyze correlations between inflammatory markers within different participant groups.

Main Methods:

• Immunoassay methods were used to measure over twenty blood and cerebrospinal fluid (CSF) inflammatory biomarkers.
• 107 participants (MCI, NIC, HC) were included in the study.
• Group comparisons and in-group correlation analyses were performed.

Main Results:

• CSF osteopontin and YKL-40 were significantly elevated in the MCI group.
• Serum C-reactive protein and interleukin-6 were significantly higher in the NIC group compared to MCI and HC groups.
• Stronger correlations between interleukin-1β and inflammasome markers were found in the serum of the MCI group, indicating CNS inflammatory activation and interleukin-1β pathway upregulation.

Conclusions:

• Specific inflammatory biomarkers in CSF are elevated in MCI patients.
• Distinct serum inflammatory profiles were observed in non-impaired controls versus MCI and healthy controls.
• Findings suggest localized CNS inflammation and systemic inflammatory pathway alterations in MCI, highlighting potential diagnostic and therapeutic targets.