α-Lipoic acid alleviates dextran sulfate sodium salt-induced ulcerative colitis via modulating the Keap1-Nrf2 signaling pathway and inhibiting ferroptosis

J Sci Food Agric. 2024 Feb;104(3):1679-1690. doi: 10.1002/jsfa.13053. Epub 2023 Nov 15.

Abstract

Background: Inflammatory bowel disease (IBD) is a chronically relapsing inflammatory disease with severe diarrhea, fatigue and weight loss. α-Lipoic acid (LA), a well-known antioxidant, is able to scavenge reactive oxygen species (ROS) and maintain a healthy cellular redox state. However, the role of LA in protecting IBD is still unclear. Hence the aim of this research was to investigate the protective effect of LA on dextran sulfate sodium salt-induced ulcerative colitis (UC) and its underlying mechanism.

Results: Here, our findings showed that LA significantly alleviated UC symptoms and the overproduction of pro-inflammatory cytokines in UC mice. In addition, LA treatment inhibited intestinal cell apoptosis by regulating the expression levels of p53/caspase-3 pathway-related protein in UC mice. Meanwhile, the inhibitory effects of LA on colonic oxidative stress and ferroptosis were revealed. Our study further demonstrated that LA treatment could regulate the Kelch-like ECH-associating protein 1 (Keap1)-nuclear factor E2-related factor 2 (Nrf2) signaling pathway. Interestingly, we confirmed that LA inhibited ferroptosis by attenuating endoplasmic reticulum stress and suppressing apoptosis in erastin-induced ferroptosis model in vitro.

Conclusion: Taken together, this study's findings suggest that LA could be considered as a therapeutic agent protecting against IBD. © 2023 Society of Chemical Industry.

Keywords: ferroptosis; oxidative stress; ulcerative colitis; α-lipoic acid.

MeSH terms

  • Animals
  • Colitis* / chemically induced
  • Colitis, Ulcerative* / chemically induced
  • Colitis, Ulcerative* / drug therapy
  • Dextran Sulfate / adverse effects
  • Disease Models, Animal
  • Ferroptosis*
  • Kelch-Like ECH-Associated Protein 1 / genetics
  • Kelch-Like ECH-Associated Protein 1 / metabolism
  • Mice
  • Mice, Inbred C57BL
  • NF-E2-Related Factor 2 / genetics
  • NF-E2-Related Factor 2 / metabolism
  • Signal Transduction
  • Sodium Chloride / metabolism
  • Thioctic Acid* / pharmacology

Substances

  • Thioctic Acid
  • Kelch-Like ECH-Associated Protein 1
  • NF-E2-Related Factor 2
  • Dextran Sulfate
  • Sodium Chloride
  • Keap1 protein, mouse