Trigonella foenum-graecum Methanolic Extract on Isolated Smooth Muscles and Acetylcholinesterase Enzyme: An In Vitro and Mechanistic In Silico Investigation.

Results: When tested on the baseline of isolated tissues, Tfg.Cr was devoid of any activity (stimulant or relaxant) till 10 mg/ml. This is an interesting finding, keeping in mind that the fenugreek seeds are used to alleviate constipation and diarrhoea. When Tfg.Cr was tried for any potential AChE inhibitory activity, it did show an inhibitory effect in increasing concentrations (47-380 µg/ml). This inhibitory effect was comparable to the effect produced by a standard AChE inhibitor physostigmine. One of the known fenugreek constituents, diosgenin, was also tested, and it also showed an AChE inhibitory effect in a concentration-dependent manner (11-190 µg/ml). Interaction between diosgenin and AChE was further investigated by molecular docking and molecular dynamics simulations for 100 ns, which showed that diosgenin interacted with the active-site gorge of AChE through hydrophobic, pi-pi stacking, and hydrogen bonds with various amino acids of the AChE enzyme. Conclusion: The results show that the fenugreek extract does not possess any GI stimulant or relaxant activity even though it is used traditionally in GI motility disorders. The extract and diosgenin could inhibit the AChE enzyme pointing towards their benefit to enhance the memory.