Eleutheroside E attenuates isoflurane-induced cognitive dysfunction by regulating the α7-nAChR-NMDAR pathway

Area of Science:

• Neuroscience
• Pharmacology
• Gerontology

Background:

• Anesthetic agents like isoflurane (ISO) can cause cognitive dysfunction, particularly in elderly surgical patients.
• Cognitive impairment poses a significant health risk to the aging population undergoing surgery.
• Eleutheroside E (EE), derived from Eleutherococcus senticosus, shows promise in protecting cognitive functions.

Purpose of the Study:

• To investigate the neuroprotective effects of EE against ISO-induced cognitive dysfunction in aged rats.
• To explore the underlying molecular mechanisms of EE's action on learning and memory pathways.

Main Methods:

• Aged rats were exposed to ISO to induce cognitive deficits.
• Learning and memory were evaluated using the novel object recognition and Morris water maze tests.
• Levels of acetylcholine (ACh), choline acetyltransferase (ChAT), α7-nicotinic acetylcholine receptors (α7-nAChR), and NR2B were measured in the hippocampus and serum.

Main Results:

• ISO exposure led to impaired learning and memory in aged rats, evidenced by reduced novel object preference and time in the target quadrant.
• EE administration (50 mg/kg) significantly alleviated ISO-induced amnesia.
• EE reversed the ISO-induced decrease in hippocampal and serum ACh levels and the downregulation of ChAT, α7-nAChR, and NR2B expression.

Conclusions:

• EE demonstrates significant neuroprotective potential against isoflurane-induced cognitive dysfunction.
• EE may exert its effects by enhancing choline acetyltransferase activity, thereby promoting acetylcholine synthesis and modulating the α7-nAChR-NR2B complex.
• EE represents a potential therapeutic candidate for preventing or treating anesthetic-induced cognitive deficits in elderly individuals.