1. Academic Validation
  2. Peimine, an Anti-Inflammatory Compound from Chinese Herbal Extracts, Modulates Muscle-Type Nicotinic Receptors

Peimine, an Anti-Inflammatory Compound from Chinese Herbal Extracts, Modulates Muscle-Type Nicotinic Receptors

  • Int J Mol Sci. 2021 Oct 19;22(20):11287. doi: 10.3390/ijms222011287.
Armando Alberola-Die 1 José Antonio Encinar 2 Raúl Cobo 1 Gregorio Fernández-Ballester 2 José Manuel González-Ros 2 Isabel Ivorra 1 Andrés Morales 1
Affiliations

Affiliations

  • 1 División de Fisiología, Departamento de Fisiología, Genética y Microbiología, Universidad de Alicante, Apdo. 99, E-03080 Alicante, Spain.
  • 2 Instituto de Investigación, Desarrollo e Innovación en Biotecnología Sanitaria de Elche (IDiBE), Universidad Miguel Hernández, E-03202 Elche, Spain.
Abstract

Fritillaria bulbs are used in Traditional Chinese Medicine to treat several illnesses. Peimine (Pm), an anti-inflammatory compound from Fritillaria, is known to inhibit some voltage-dependent ion channels and muscarinic receptors, but its interaction with ligand-gated ion channels remains unexplored. We have studied if Pm affects nicotinic acetylcholine receptors (nAChRs), since they play broad functional roles, both in the nervous system and non-neuronal tissues. Muscle-type nAChRs were incorporated to Xenopus oocytes and the action of Pm on the membrane currents elicited by ACh (IAChs) was assessed. Functional studies were combined with virtual docking and molecular dynamics assays. Co-application of ACh and Pm reversibly blocked IACh, with an IC50 in the low micromolar range. Pm inhibited nAChR by: (i) open-channel blockade, evidenced by the voltage-dependent inhibition of IAch, (ii) enhancement of nAChR desensitization, revealed by both an accelerated IACh decay and a decelerated IACh deactivation, and (iii) resting-nAChR blockade, deduced from the IACh inhibition elicited by Pm when applied before ACh superfusion. In good concordance, virtual docking and molecular dynamics assays demonstrated that Pm binds to different sites at the nAChR, mostly at the transmembrane domain. Thus, Pm from Fritillaria bulbs, considered therapeutic herbs, targets nAChRs with high affinity, which might account for its anti-inflammatory actions.

Keywords

Xenopus oocytes; anti-inflammatory compound; dynamics simulations; electrophysiological recordings; molecular docking; nicotinic receptors; peimine; traditional Chinese medicine.

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