# Neuroprotective Effect of Nor-Prenylated Acylphloroglucinols from Hypericum perforatum L. (St John’s Wort) in the MPTP-Induced Zebrafish Model

## TL;DR

This study identifies new compounds from St John’s wort that may help treat Parkinson’s disease by reducing oxidative stress in zebrafish models.

## Contribution

Five new nor-prenylated acylphloroglucinols from St John’s wort are isolated and tested for neuroprotective effects in a Parkinson’s disease model.

## Key findings

- Compound 9 improved movement and increased speed in MPTP-induced Parkinson’s zebrafish larvae.
- Compound 9 enhanced SOD activity and reduced ROS production in a dose-dependent manner.
- The study suggests these compounds may alleviate Parkinson’s symptoms by inhibiting oxidative stress.

## Abstract

Hypericum perforatum L. (St John’s wort) has been widely studied and used for antidepressant treatment, as well as, rarely, featuring in studies on its chemical composition for Parkinson’s disease (PD) treatment. Five new nor-prenylated acylphloroglucinols with a cyclohexanone core, norperforatums A–E (1–5), together with four known analogs [(2R,3R,4S,6R)-3-methyl-4,6-di(3-methyl-2-butenyl)-2-(2-methyl-1-oxopropyl)-3-(4-methyl-3-pentenyl)cyclohexanone (6), hyperscabrin B (7), (2R,3R,4S,6R)-6-methoxycarbonyl-3-methyl-4,6-di(3-methyl-2-butenyl)-2-(2-methyl-1-oxopropyl)-3-(4-methyl-3-pentenyl)cyclohexanone (8), and hyperscabin K (9)], were isolated from the aerial parts of H. perforatum. The structures and absolute configurations of the new compounds were characterized by multiple spectroscopic means, including nuclear magnetic resonance (NMR), high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), ultraviolet visible absorption spectroscopy (UV), infrared spectroscopy (IR), calculated electronic circular dichroism (ECD) data, and X-ray signal crystal diffraction. In addition, the efficacy of these isolations was evaluated against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD in zebrafish larvae. Compound 9 had the best therapeutic effect, by significantly increasing the total distance traveled and the mean speed of movement in PD dyskinesia zebrafish larvae. Moreover, it enhanced superoxide dismutase (SOD) activity and inhibited reactive oxygen species (ROS) production in a dose-dependent manner. These results suggest that compound 9 may have ameliorative effects on PD symptoms by inhibiting oxidative stress. This study provides new insights into the treatment of H. perforatum for PD.