27-Hydroxycholesterol Alters Synaptic Structural and Functional Plasticity in Hippocampal Neuronal Cultures

Area of Science:

• Neuroscience
• Biochemistry

Background:

• 27-hydroxycholesterol (27-OHC) is a key cholesterol derivative found in the brain.
• Understanding its impact on neuronal health is crucial for neurodegenerative disease research.

Purpose of the Study:

• To investigate the neurotoxic effects of 27-hydroxycholesterol (27-OHC) on synaptic structural and functional plasticity.
• To determine the dose-dependent impact of 27-OHC on primary hippocampal neurons.

Main Methods:

• Primary hippocampal neurons from Sprague-Dawley rats were treated with varying doses of 27-OHC (0-30 μM).
• Cell viability was assessed using MTT and CCK-8 assays.
• Neurite morphology, synaptic ultrastructure, and key synaptic protein expression (SYP, PSD-95, SNAP-25, GAP-43, MAP2, Arc) were analyzed via immunofluorescence, electron microscopy, qPCR, and Western blot.

Main Results:

• 27-OHC treatment led to dose-dependent cell death.
• Significant reductions in neurite number and length were observed.
• Alterations in synaptic ultrastructure and downregulated expression of critical synaptic proteins were evident.

Conclusions:

• 27-hydroxycholesterol exhibits deleterious effects on synaptic structural and functional plasticity.
• These findings suggest 27-OHC contributes to neurotoxicity, potentially impacting brain health.