Huperzine A attenuates epileptic seizures via enhancing dCA1-projecting septal cholinergic transmission

Acta Pharmacol Sin. 2025 Aug;46(8):2151-2162. doi: 10.1038/s41401-025-01522-w. Epub 2025 Mar 26.

Abstract

Cholinergic transmission, independent of classical glutamatergic and GABAergic signaling, critically plays a crucial role in epilepsy. Huperzine A (Hup A), an acetylcholinesterase (AChE) inhibitor, exerts potent anticonvulsant activity, but its mechanism of action within cholinergic circuits remains unclear. Here, we show that Hup A mitigates epileptic seizures by enhancing hippocampal dorsal CA1 (dCA1)-projecting cholinergic transmission. We found that systemic injection of Hup A not only reduces seizures in acute models, including the maximal-electroshock seizure (MES), pentylenetetrazol (PTZ), and kainic acid (KA) models but also alleviates the seizure severity in chronic epilepsy models induced by kindling and KA, indicating a broad-spectrum anti-seizure efficacy. Interestingly, using immunohistochemistry, viral tracing, and in vivo fiber photometry, we found that Hup A selectively inhibits AChE in the dCA1 rather than in other hippocampal subregions or cortex, enhancing dCA1-projecting septal cholinergic transmission. Significantly, selective ablation of septal ChAT+ neurons reversed the anti-seizure effects of Hup A. We further identified that α7 nicotinic acetylcholine receptors in the dCA1 region mediate the anti-seizures cholinergic circuit modulated by Hup A. Together, our results demonstrate that Hup A exerts broad-spectrum anti-seizure efficacy via modulating dCA1-projecting septal cholinergic transmission, providing potential therapeutic avenues for epilepsy through targeted cholinergic modulation.

Keywords: cholinergic circuit; epilepsy; hippocampal dorsal CA1 region; huperzine A; α7 nicotinic acetylcholine receptor.

MeSH terms

  • Acetylcholinesterase / metabolism
  • Alkaloids* / pharmacology
  • Alkaloids* / therapeutic use
  • Animals
  • Anticonvulsants* / pharmacology
  • Anticonvulsants* / therapeutic use
  • CA1 Region, Hippocampal* / drug effects
  • CA1 Region, Hippocampal* / metabolism
  • Cholinesterase Inhibitors* / pharmacology
  • Cholinesterase Inhibitors* / therapeutic use
  • Disease Models, Animal
  • Epilepsy* / drug therapy
  • Kainic Acid
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Seizures* / drug therapy
  • Sesquiterpenes* / pharmacology
  • Sesquiterpenes* / therapeutic use
  • Synaptic Transmission / drug effects
  • alpha7 Nicotinic Acetylcholine Receptor / metabolism

Substances

  • huperzine A
  • Sesquiterpenes
  • Alkaloids
  • Cholinesterase Inhibitors
  • Anticonvulsants
  • alpha7 Nicotinic Acetylcholine Receptor
  • Acetylcholinesterase
  • Kainic Acid