Effect of peptide hydrolysates from riceberry on reducing endoplasmic reticulum stress in cells

Abstract

Oxidative stress, resulting from an imbalance between reactive oxygen species (ROS) and antioxidants, contributes to diseases and induces endoplasmic reticulum (ER) stress. Antioxidants can mitigate ER stress. We investigated synthetic peptides from riceberry rice hydrolysates against ER stress. Ten peptides were evaluated for toxicity and antioxidant activity in SH-SY5Y and L929 cell lines. Peptides ID 3 to ID 5 ,and ID 10 showed significant antioxidant activity protecting cells from oxidative stress induced by IAA and H2O2. These peptides alleviated ER stress induced by TM, as observed through fluorescence microscopy analysis using ConA dye. Peptides ID 3 to 5 reduced ConA intensity compared to TM-treated cells, indicating their potential in reducing ER stress. Peptide ID 3 and ID 4 exhibited higher Mag-Fluo4 intensity compared to TM group, signifying its role in controlling calcium ion levels and potentially reducing ER stress. Statistical analysis confirmed significant differences (p<0.05). These findings highlight the antioxidant and ER stress-reducing potential of riceberry peptides, particularly ID 3 and 4. Further investigations are needed to understand their mechanisms and therapeutic applications for managing oxidative- and ER stress-related diseases.