Modulation of LPS-Induced Neurodegeneration by Intestinal Helminth Infection in Ageing Mice

Area of Science:

• Neuroimmunology
• Parasitology
• Aging Research

Background:

• Parasitic helminths can modulate host immune responses, potentially impacting chronic inflammatory conditions.
• Age-related neuroinflammation is a growing concern linked to neurodegenerative diseases.

Purpose of the Study:

• To investigate the impact of nematode infection on age-related neuroinflammation and neurodegeneration.
• To examine the role of macrophage populations (M1 and M2) in the brain during helminth infection and neuroinflammation.

Main Methods:

• Utilized C57BL/6 mice, including transgenic models predisposed to neurodegeneration.
• Induced systemic inflammation using intraperitoneal lipopolysaccharide (LPS).
• Infected mice with the nematode Heligmosomoides polygyrus.

Main Results:

• Prolonged nematode infection exacerbated LPS-induced neuroinflammation and neurodegeneration.
• Observed increased M1 macrophages, reduced survivin, elevated APP and GFAP expression, and chitin deposition in the brain.
• Transgenic mice showed similar changes, indicating relevance to Alzheimer's disease pathology.
• Higher M2 macrophage populations in infected-only mice correlated with improved performance in the forced swim test.

Conclusions:

• Nematode infection can worsen neurodegenerative processes, particularly in the context of systemic inflammation.
• Macrophage polarization (M1 vs. M2) plays a critical role in mediating these effects.
• Findings suggest potential implications for aging health strategies and disease monitoring, highlighting the complex interplay between parasitic infections and neurodegeneration.