Impact of hypericin and Hypericum perforatum L. (St. John's Wort) extract on oxidative stress and neurotrophic factors during the acute phase of spinal cord injury in male rats.

Abstract

A randomized, controlled, experimental animal study. This study investigates the influence of Hypericum perforatum (St. John's Wort) and its active compound, hypericin, influence on oxidative stress markers and neurotrophic factor expression during the acute phase of SCI in male rats. University animal research facility equipped with dedicated surgical suites for SCI induction and controlled-environment housing for rodents. SCI was induced in Wistar rats through a contusion injury model. The treatment groups received either hypericin (50/100 mg/kg, i.p.) or Hypericum perforatum extract (50/100 mg/kg, i.p.) for two weeks. Motor function was evaluated with the Basso, Beattie, and Bresnahan (BBB) test, and nociceptive sensitivity was assessed using the tail flick test. Serum levels of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), nitric oxide (NO), and reactive oxygen species (ROS) were measured. Histological analysis of myelination was conducted using Luxol fast blue staining. SCI led to a significant decline in BBB scores, an increase in oxidative stress markers (NO, ROS), and a reduction in BDNF levels. Treatment with 100 mg/kg hypericin notably improved BBB scores (p < 0.00001), reduced NO and ROS levels (p < 0.0001), and increased BDNF expression compared to untreated SCI rats. Histological examination showed less demyelination in the treated groups, with hypericin demonstrating more pronounced effects than Hypericum perforatum extract. Hypericin exhibited strong neuroprotective properties by reducing oxidative stress, enhancing neurotrophic factor expression, and preserving myelin integrity. These findings highlight its potential as a therapeutic agent for reducing secondary damage following SCI.