Pharmacological basis for the traditional use of Myrica salicifolia root extract in gut motility disorders via cholinergic and calcium/PDE modulation.

BACKGROUND AND AIM: This study was carried out to evaluate the possible gut modulatory and antibacterial activities of Myrica salicifolia root extract (Ms.Cr). EXPERIMENTAL PROCEDURE: Gas Chromatography-Mass Spectrometry (GC-MS) analysis was conducted for chemical profiling, while FTIR analyzed the chemical bonds. Mice were used for in vivo experiments, while possible pharmacodynamics were explored in rabbit jejunal tissues. RESULTS AND CONCLUSION: GC-MS analysis identified 16 metabolites, while mice administered with lower doses of Ms.Cr (50 and 100 mg/kg) causes increase in the count of wet feces and the total number of fecal outputs, which was significantly reduced in the pre-atropinized mice. At higher doses of 200 and 400 mg/kg, Ms.Cr showed respective protection of 40% and 80% in mice in castor oil induced diarrhea. In jejunal tissues, lower concentrations of Ms.Cr increased the spontaneous contractions followed by complete relaxation at higher concentrations. Further, Ms.Cr caused concentration-dependent (1.0-5.0 mg/mL) relaxation of high K+-induced contractions, similar to papaverine. Preincubated jejunal tissues with Ms.Cr shifted the Ca++ concentration-response curves (CRCs) towards right with suppression of the maximum response, similar to verapamil, thus confirming Ca++ channel blocking activity. Similar to papaverine, preincubation of tissues with 3 and 5 mg/mL of Ms.Cr, caused shift in isoprenaline CRCs towards left, thus showing phosphodiesterase inhibition. Ms.Cr showed an antimicrobial effect against pathogenic gut bacteria including E. coli, Sh. sonnei, S. typhimurium and ESβL (extended-spectrum beta-lactamase)-producing E. coli. Thus, this research provides a solid foundation for the therapeutic uses of M. salicifolia in gut motility-related disorders.