# Protective Effect of Gastrodia elata Polysaccharide GEP-2 Against Oxidative Stress in Intestinal Epithelial NCM460 Cells

## TL;DR

This study shows that GEP-2, a compound from Gastrodia elata, protects intestinal cells from oxidative stress by boosting antioxidant defenses and activating key signaling pathways.

## Contribution

The study reveals the molecular mechanisms by which GEP-2 protects intestinal epithelial cells from oxidative stress.

## Key findings

- GEP-2 pretreatment improved cell viability and reduced oxidative damage in H2O2-treated NCM460 cells.
- GEP-2 activated the Nrf2/NQO1 antioxidant pathway and the JAK/STAT survival signaling pathway.
- Transcriptomic analysis showed upregulation of glutathione metabolism and downregulation of inflammatory pathways.

## Abstract

Oxidative stress in intestinal epithelial cells has been increasingly recognized as a key factor in various intestinal disorders. Gastrodia elata polysaccharide-2 (GEP-2), a water-soluble polysaccharide known for its antioxidant properties, has shown potential against intestinal injury. However, its effects on intestinal epithelial cells and the molecular mechanisms involved are not yet fully understood. In this study, we established a hydrogen peroxide (H2O2)-induced oxidative stress model using human colonic epithelial cells (NCM460) to evaluate the protective effects of GEP-2. We assessed cell viability, antioxidant enzyme activities, reactive oxygen species (ROS) levels, and mitochondrial membrane potential (MMP). The results demonstrated that GEP-2 pretreatment significantly improved the viability of NCM460 cells subjected to H2O2 damage. Additionally, it could enhance the antioxidant defense, reduce the levels of ROS, malondialdehyde (MDA), and maintain the MMP. Transcriptomic analysis identified 169 differentially expressed genes upregulated in the glutathione metabolism. JAK-STAT pathway and downregulated in inflammation. Furthermore, it was shown that GEP-2 treatment activated the Nuclear factor erythroid 2-related factor 2 (Nrf2)/quinone oxidoreductase 1 (NQO1)-mediated antioxidant response and promoted the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway. Therefore, GEP-2 exerts multi-targeted cell protection by coordinating the Nrf2/NQO1 antioxidant axis and the JAK/STAT survival signaling pathway, providing a theoretical basis for the development of novel antioxidants.