Differential hippocampal protein expression between normal aged rats and aged rats with postoperative cognitive...

Area of Science:

• Neuroscience
• Biochemistry
• Gerontology

Background:

• Postoperative cognitive dysfunction (POCD) is a common complication in aged individuals.
• The underlying molecular mechanisms of POCD, particularly hippocampal protein alterations, remain incompletely understood.

Purpose of the Study:

• To investigate differential hippocampal protein expression in aged rats with POCD compared to normal controls.
• To identify molecular pathways and proteins implicated in the pathogenesis of POCD.

Main Methods:

• Aged rats underwent splenectomy under isoflurane anesthesia to induce POCD, with a control group receiving oxygen.
• Cognitive function was assessed using the Y-maze test.
• Hippocampal proteomic analysis was performed using 2D-gel electrophoresis and MALDI-TOF MS, with RT-qPCR for validation.

Main Results:

• POCD rats exhibited significant alterations in 21 hippocampal proteins compared to controls.
• Affected proteins were functionally linked to synaptic plasticity, oxidative stress, energy production, neuroinflammation, and glutamate metabolism.
• Expression levels of fatty acid binding protein 7, glutamate dehydrogenase 1, and glutamine synthetase were significantly altered, suggesting astrocytic involvement.

Conclusions:

• Neuroinflammation, glutamate toxicity, and oxidative stress are likely key contributors to POCD pathogenesis in aged rats.
• Astrocytic function may play a critical role in the development of POCD.