Trimethoxyflavones from Ocimum basilicum L. leaves improve long term memory in mice by modulating multiple pathways

Area of Science:

• Pharmacology
• Neuroscience
• Natural Products Chemistry

Background:

• Ocimum basilicum L. (OB) leaves have traditional uses for brain disorders.
• Scientific evidence suggests Ocimum basilicum L. leave extract (OBE) improves cognition.
• The specific compounds and mechanisms behind OBE's cognitive effects were previously unknown.

Purpose of the Study:

• To isolate and identify compounds in OBE responsible for memory enhancement.
• To elucidate the mechanism of action underlying the memory improvement effects.

Main Methods:

• Bioassay-guided fractionation using in-vitro acetylcholinesterase (AChE) inhibition and antioxidant (DPPH scavenging) assays.
• Characterization of isolated compounds via spectroscopic techniques (FTIR, NMR, MS).
• In-silico molecular docking and in-vivo studies using a scopolamine-induced amnesia mouse model.

Main Results:

• Two trimethoxy flavones, 5,7-dihydroxy-3',4',5'-trimethoxyflavone (S1) and 3-hydroxy-3',4',5'-trimethoxyflavone (S2), were isolated.
• Both S1 and S2 reversed scopolamine-induced cognitive impairment in mice.
• Compounds reduced markers of oxidative stress, inflammation, and apoptosis, while enhancing antioxidant levels and improving hippocampus histology.

Conclusions:

• Trimethoxy flavones are the key memory-enhancing compounds in OBE.
• These compounds exert their effects through anticholinergic, antioxidant, anti-inflammatory, and anti-apoptotic mechanisms.
• Isolated trimethoxy flavones show potential as therapeutic agents for cognitive disorders.