Abstract

Background/Objectives: The intestinal epithelium is a one-cell-thick layer lining the mucosal surface that both absorbs nutrients from food and serves as a barrier to maintain mucosal integrity. Impairment of intestinal barrier integrity allows the passage of excluded substances, which induce various gastrointestinal disorders like inflammatory bowel disease (IBD). Accordingly, intestinal health and diseases are highly associated with intestinal barrier integrity and function, which are regulated by the mucous layer and tight junction structures of epithelial cells. Therefore, this study was dedicated to investigating the effect of hydrogen peroxide (H₂O₂) as an oxidative stress inducer as well as focusing on the antioxidant effects of the natural product curcumin (Cur) against oxidative stress in Caco-2 cells. Methods: Caco-2 cells were treated with 10 μmol/L Cur and then exposed to 250 μmol/L H₂O₂. Caco-2 cell viability was measured by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide (MTT) assay, Reactive Oxygen Species (ROS) were detected by dihydrodichlorofluorescein (H2DCF) cell-permeant probe. Cu/Zn superoxide dismutase (SOD) activities, Catalase (Cat), glutathione (GSH) levels, lipid peroxidation, mRNA, and Western blot were assayed with commercially available kits. Results: Cur enhanced the viability of H₂O₂-treated Caco-2 cells in a dose-dependent manner. H₂O₂-treated Caco-2 cells exhibited the elevated levels of depletion in GSH, SOD and Cat activities, ROS productions, and lipid peroxidation while Cur reversed the H₂O₂-induced oxidative stress effects. The treatment of H₂O₂-induced Caco-2 cells with Cur improved the mRNA gene and protein levels of claudin-1 and glutathione peroxidase 4 (GPX4). Conclusions: The protective effects of Cur against H₂O₂-mediated oxidative damage in intestinal Caco-2 cells may be mediated through the GSH pathway.

References

1. Turner JR. Intestinal mucosal barrier function in health and disease. Nat Rev Immunol. 2009;9(11):799–809.
2. Stalgis C, Deepak P, Mehandru S, Colombel JF. Rational Combination Therapy to Overcome the Plateau of Drug Efficacy in Inflammatory Bowel Disease. Gastroenterology. 2021;161(2):394–9.
3. Cai Z, Wang S, Li J. Treatment of Inflammatory Bowel Disease: A Comprehensive Review. Front Med (Lausanne). 2021;8(December):1–24.
4. Neurath MF. Current and emerging therapeutic targets for IBD. Nat Rev Gastroenterol Hepatol. 2017;14(5):269–78.
5. Shen L. Tight junctions on the move: Molecular mechanisms for epithelial barrier regulation. Ann N Y Acad Sci. 2012;1258(1):9–18.
6. Hasegawa T, Mizugaki A, Inoue Y, Kato H, Murakami H. Cystine reduces tight junction permeability and intestinal inflammation induced by oxidative stress in Caco-2 cells. Amino Acids [Internet]. 2021;53(7):1021–32. Available from: https://doi.org/10.1007/s00726-021-03001-y
7. Artursson P, Palm K, Luthman K. Caco-2 monolayers in experimental and theoretical predictions of drug transport. Adv Drug Deliv Rev. 2012;64(SUPPL.):280–9.
8. Kaak JL, Lobo de Sá FD, Turner JR, Schulzke JD, Bücker R. Unraveling the intestinal epithelial barrier in cyanotoxin microcystin-treated Caco-2 cell monolayers. Ann N Y Acad Sci. 2022;1516(1):188–96.
9. Radhakrishna Rao. Oxidative Stress-Induced Disruption of Epithelial and Endothelial Tight Junctions. Front Biosci. 2018;13(901):7210–26.
10. Gupta SC, Patchva S, Aggarwal BB. Therapeutic roles of curcumin: Lessons learned from clinical trials. AAPS Journal. 2013;15(1):195–218.
11. Wang N, Wang G, Hao JX, Ma JJ, Wang Y, Jiang XY, et al. Curcumin ameliorates hydrogen peroxide-induced epithelial barrier disruption by upregulating heme oxygenase-1 expression in human intestinal epithelial cells. Dig Dis Sci. 2012;57(7):1792–801.
12. Wang J, Ghosh SS, Ghosh S. Curcumin improves intestinal barrier function: Modulation of intracellular signaling, and organization of tight junctions. Am J Physiol Cell Physiol. 2017;312(4):C438–45.
13. Peng Y, Ao M, Dong B, Jiang Y, Yu L, Chen Z, et al. Anti-inflammatory effects of curcumin in the inflammatory diseases: Status, limitations and countermeasures. Drug Des Devel Ther. 2021;15:4503–25.
14. Zhang H, Tsao R. Dietary polyphenols, oxidative stress and antioxidant and anti-inflammatory effects. Curr Opin Food Sci [Internet]. 2016;8:33–42. Available from: http://dx.doi.org/10.1016/j.cofs.2016.02.002
15. Jomova K, Raptova R, Alomar SY, Alwasel SH, Nepovimova E, Kuca K, et al. Reactive oxygen species, toxicity, oxidative stress, and antioxidants: chronic diseases and aging [Internet]. Vol. 97, Archives of Toxicology. Springer Berlin Heidelberg; 2023. 2499–2574 p. Available from: https://doi.org/10.1007/s00204-023-03562-9
16. Pat Y, Yazici D, D’avino P, Li M, Ardicli S, Ardicli O, et al. Recent advances in the epithelial barrier theory. Int Immunol. 2024;36(5):211–22.
17. Antoni L, Nuding S, Wehkamp J, Stange EF. Intestinal barrier in inflammatory bowel disease. World J Gastroenterol. 2014;20(5):1165–79.
18. Sahoo DK, Heilmann RM, Paital B, Patel A, Yadav VK, Wong D, et al. Oxidative stress, hormones, and effects of natural antioxidants on intestinal inflammation in inflammatory bowel disease. Front Endocrinol (Lausanne). 2023;14(August):1–24.
19. Zou Y, Xiang Q, Wang J, Peng J, Wei H. Oregano Essential Oil Improves Intestinal Morphology and Expression of Tight Junction Proteins Associated with Modulation of Selected Intestinal Bacteria and Immune Status in a Pig Model. Biomed Res Int. 2016;2016.
20. Dong Y, Hou Q, Lei J, Wolf PG, Ayansola H, Zhang B. Quercetin Alleviates Intestinal Oxidative Damage Induced by H2O2 via Modulation of GSH: In Vitro Screening and in Vivo Evaluation in a Colitis Model of Mice. ACS Omega. 2020;5(14):8334–46.
21. Cilla A, Laparra JM, Alegria A, Barbera R, Farre R. Antioxidant effect derived from bioaccessible fractions of fruit beverages against H2O2-induced oxidative stress in Caco-2 cells. Food Chem. 2008;106(3):1180–7.
22. Audus KL, Bartel RL, Hidalgo IJ, Borchardt RT. The Use of Cultured Epithelial and Endothelial Cells for Drug Transport and Metabolism Studies. Vol. 7, Pharmaceutical Research: An Official Journal of the American Association of Pharmaceutical Scientists. 1990. p. 435–51.
23. Yamamoto-Furusho JK. Treatment of Inflammatory Bowel Disease. Rev Gastroenterol Mex. 2012;77:39–41.
24. Akram M, Ahmed A, Usmanghani K, Hannan A, Mohiuddin E, Asif M. Curcuma Longa and Curcumin: a Review Article. Romanian Journal of Biology [Internet]. 2010;55(2):65–70. Available from: http://ns.ibiol.ro/plant/volume 55/art201.pdf
25. Liu W, Zhai Y, Heng X, Che FY, Chen W, Sun D, et al. Oral bioavailability of curcumin: problems and advancements. J Drug Target. 2016;24(8):694–702.
26. Siviero A, Gallo E, Maggini V, Gori L, Mugelli A, Firenzuoli F, et al. Curcumin, a golden spice with a low bioavailability. J Herb Med [Internet]. 2015;5(2):57–70. Available from: http://dx.doi.org/10.1016/j.hermed.2015.03.001
27. Li L, Tan J, Miao Y, Lei P, Zhang Q. ROS and Autophagy: Interactions and Molecular Regulatory Mechanisms. Cell Mol Neurobiol [Internet]. 2015;35(5):615–21. Available from: http://dx.doi.org/10.1007/s10571-015-0166-x
28. Khan H, Ullah H, Nabavi SM. Mechanistic insights of hepatoprotective effects of curcumin: Therapeutic updates and future prospects. Food and Chemical Toxicology. 2019;124(December 2018):182–91.
29. Cao S, Wang C, Yan J, Li X, Wen J, Hu C. Curcumin ameliorates oxidative stress-induced intestinal barrier injury and mitochondrial damage by promoting Parkin dependent mitophagy through AMPK-TFEB signal pathway. Free Radic Biol Med [Internet]. 2020;147(September 2019):8–22. Available from: https://doi.org/10.1016/j.freeradbiomed.2019.12.004
30. Mao GD, Thomas PD, Lopaschuk GD, Poznansky MJ. Superoxide dismutase (SOD)-catalase conjugates: Role of hydrogen peroxide and the fenton reaction in SOD toxicity. Journal of Biological Chemistry. 1993;268(1):416–20.
31. Ursini F, Maiorino M. Lipid peroxidation and ferroptosis: The role of GSH and GPx4. Free Radic Biol Med. 2020;152(December 2019):175–85.
32. Li Y, Cai L, Bi Q, Sun W, Pi Y, Jiang X, et al. Genistein Alleviates Intestinal Oxidative Stress by Activating the Nrf2 Signaling Pathway in IPEC-J2 Cells. Vet Sci. 2024;11(4).