Glutathione Protects Human Retinal Pigment Epithelial Cells From Lipopolysaccharide-Induced Apoptosis and Oxidative Stress by Inhibiting The TRPM2 Channel

Anıl Selim Apa

doi:10.37212/jcnos.1872386

Glutathione Protects Human Retinal Pigment Epithelial Cells From Lipopolysaccharide-Induced Apoptosis and Oxidative Stress by Inhibiting The TRPM2 Channel

Abstract

Gram-negative bacteria's outer membranes include lipopolysaccharides (LPS), which are a major contributor to inflammatory eye disorders. LPS cause apoptosis induction and produce reactive free radicals of oxygen (ROS). In microglia, LPS-induced ROS stimulates transient receptor melastatin 2 (TRPM2), whereas glutathione (GSH) and N-(p-amylcinnamoyl) anthranilic acid (ACA) decrease their activation. Anti-apoptotic and antioxidant properties of GSH through TRPM2 inhibition were not reported in human retinal pigment epithelial (ARPE-19) cells. Therefore, the modulator action of GSH on the TRPM2-mediated molecular oxidant and apoptotic pathways in ARPE-19 was investigated. Five main groups were generated in the ARPE-19: Control, GSH (10 mM for 2 h), LPS (1 μg/ml for 24 h), LPS + GSH, and LPS + ACA (25 μM for 30 min). The amounts of ROS, mitochondrial dysfunction, apoptosis, caspases (caspase-3, -8, and -9), and cytosolic free Ca2+ were increased by the LPS incubation, while the incubations of GSH and ACA reduced their amounts. The viable cell number and viability percentage were decreased by LPS, but their viability and number were increased by the incubations of GSH and ACA. In conclusion, GSH decreased the levels of LPS caused oxidative stress and apoptosis via suppressing TRPM2 in the ARPE-19. One possible treatment agent for oxidative retinal injury and inflammatory eye diseases induced by LPS could be the GSH treatment.

Keywords

Project Number

BSN Health- Project No: 2025-02

Ethical Statement

No human and animal samples.

References

Akpınar O, Nazıroğlu M. (2026). Glutathione and TRPM2 Inhibition Reduce Amyloid-Beta and Lipopolysaccharide-Induced Apoptosis, Inflammation, and Oxidative Stress in Microglial Cells. Cell Biol Int. 50(1):e70109. https://doi.org/10.1002/cbin.70109
Ana RD, Gliszczyńska A, Sanchez-Lopez E, et al. (2023). Precision Medicines for Retinal Lipid Metabolism-Related Pathologies. J Pers Med. 13(4):635. https://doi.org/10.3390/jpm13040635
Bardak H, Uğuz AC, Bardak Y, et al. (2023). Selenium Protects ARPE-19 and ACBRI 181 Cells against High Glucose-Induced Oxidative Stress. Molecules. 28(16):5961. https://doi.org/10.3390/molecules28165961
Böhm EW, Buonfiglio F, Voigt AM, et al. (2023). Oxidative stress in the eye and its role in the pathophysiology of ocular diseases. Redox Biol. 68:102967. https://doi.org/10.1016/j.redox.2023.102967
Cao F, Liang K, Tang WW, et al. (2024). Polyvinylpyrrolidone-curcumin nanoparticles with immune regulatory and metabolism regulatory effects for the treatment of experimental autoimmune uveitis. J Control Release. 372:551-570. https://doi.org/10.1016/j.jconrel.2024.06.047
Chistyakov DV, Tiulina VV, Gancharova OS, et al. (2024) Targeting Oxidative Stress and Inflammation in the Eye: Insights from a New Model of Experimental Autoimmune Uveitis. Int J Mol Sci. 25(23):12910. https://doi.org/10.3390/ijms252312910
Çınar R, Nazıroğlu M. (2023). TRPM2 Channel Inhibition Attenuates Amyloid β42-Induced Apoptosis and Oxidative Stress in the Hippocampus of Mice. Cell Mol Neurobiol. 43(3):1335-1353. https://doi.org/10.1007/s10571-022-01253-0
Daldal H, Nazıroğlu M. (2022) Rituximab Attenuated Lipopolysaccharide-Induced Oxidative Cytotoxicity, Apoptosis, and Inflammation in the Human Retina Cells via Modulating the TRPM2 Signaling Pathways. Ocul Immunol Inflamm. 30(6):1315-1328. https://doi.org/10.1080/09273948.2022.2075400

Ertuğrul A, Özkaya D, Nazıroğlu M. (2023) Curcumin attenuates hydroxychloroquine-mediated apoptosis and oxidative stress via the inhibition of TRPM2 channel signalling pathways in a retinal pigment epithelium cell line. Graefes Arch Clin Exp Ophthalmol. 261(10):2829-2844. https://doi.org/10.1007/s00417-023-06082-5
Ertuğrul A. (2024). Lipopolysaccharide induces apoptosis and oxidative cytotoxicity through stimulation of the TRPV1 channel in retinal pigment epithelium cell line. J Cell Neurosci Oxid Stress. 16(3): 1229-1236. https://doi.org/10.37212/jcnos.1609591
Huster D, Hjelle OP, Haug FM, Nagelhus EA, Reichelt W, Ottersen OP. (1998). Subcellular compartmentation of glutathione and glutathione precursors. A high resolution immunogold analysis of the outer retina of guinea pig. Anat Embryol (Berl). 198(4):277-287. https://doi.org/10.1007/s004290050184
Joshi DC, Bakowska JC. (2011). Determination of mitochondrial membrane potential and reactive oxygen species in live rat cortical neurons. J Vis Exp. 51: 2704. https://doi.org/10.3791/2704
Kraft R, Grimm C, Frenzel H, Harteneck C. (2006). Inhibition of TRPM2 cation channels by N-(p-amylcinnamoyl)anthranilic acid. Br J Pharmacol. 148(3):264-273. https://doi.org/10.1038/sj.bjp.0706739.
Li GY, Fan B, Zheng YC. (2010). Calcium overload is a critical step in programmed necrosis of ARPE-19 cells induced by high concentration H₂O₂. Biomed Environ Sci. 23(5):371-377. https://doi.org/10.1016/S0895-3988(10)60078-5
Li Y, Wang F. (2025). Investigation Into the Pathogenesis of Type 2 Cardiorenal Syndrome via the ROS-TRPM2 Signaling Axis. Front Biosci (Landmark Ed). 30(5):27094. https://doi.org/10.31083/FBL27094
Martins B, Boia R, Correia D, et al. (2025). Retinal pigment epithelium derived extracellular vesicles mediate outer blood retinal barrier disruption in response to AMD-related stress. Cell Commun Signal. 23(1):542. https://doi.org/10.1186/s12964-025-02587-0
Meléndez García R, Arredondo Zamarripa D, Arnold E, et al. (2016). Prolactin protects retinal pigment epithelium by inhibiting sirtuin 2-dependent cell death. EBioMedicine. 35-49. https://doi.org/10.1016/j.ebiom.2016.03.048.
Ozal SA, Turkekul K, Gurlu V, Guclu H, Erdogan S. (2018). Esculetin Protects Human Retinal Pigment Epithelial Cells from Lipopolysaccharide-induced Inflammation and Cell Death. Curr Eye Res. 43(9):1169-1176. https://doi.org/10.1080/02713683.2018.1481517
Özkaya D, Shu X, Nazıroğlu M. (2021). Deletion of Mitochondrial Translocator Protein (TSPO) Gene Decreases Oxidative Retinal Pigment Epithelial Cell Death via Modulation of TRPM2 Channel. Biology (Basel). 10(5):382. https://doi.org/10.3390/biology10050382
Panvini AR, Gvritishvili A, Galvan H, et al. (2022). Differential mitochondrial and cellular responses between H vs. J mtDNA haplogroup-containing human RPE transmitochondrial cybrid cells. Exp Eye Res. 219:109013. https://doi.org/10.1016/j.exer.2022.109013
Saddala MS, Lennikov A, Mukwaya A, et al. (2020). Discovery of novel L-type voltage-gated calcium channel blockers and application for the prevention of inflammation and angiogenesis. JNeuroinflammation. 17(1):132. https://doi.org/10.1186/s12974-020-01801-9.
Shen M, Xu B. (2025). Rosmarinic Acid Mitigates Lipopolysaccharide-Induced Inflammation and Oxidative Stress in Human Corneal Epithelial Cells as an In Vitro Keratitis Cell Model. J Ocul Pharmacol Ther. 41(10):573-581. https://doi.org/10.1177/10807683251366780
Srejovic JV, Muric MD, Jakovljevic VL, et al. (2024) Molecular and Cellular Mechanisms Involved in the Pathophysiology of Retinal Vascular Disease-Interplay Between Inflammation and Oxidative Stress. Int J Mol Sci. 25(21):11850. https://doi.org/10.3390/ijms252111850.
Sternberg P Jr, Davidson PC, Jones DP, Hagen TM, Reed RL, Drews-Botsch C. (1993). Protection of retinal pigment epithelium from oxidative injury by glutathione and precursors. Invest Ophthalmol Vis Sci. 34(13):3661-3668.
Strauss O. (2005). The retinal pigment epithelium in visual function. Physiol Rev. 85(3):845-881. https://doi.org/10.1152/physrev.00021.2004
Sun Y, Zheng Y, Wang C, Liu Y. (2018). Glutathione depletion induces ferroptosis, autophagy, and premature cell senescence in retinal pigment epithelial cells. Cell Death Dis. 9(7):753. https://doi.org/10.1038/s41419-018-0794-4
Wang C, Li H, Wang T, et al. (2025). The gut-eye axis in blinding eye diseases: microbiota-driven immune dysregulation and immunomodulatory therapies. Int Ophthalmol. 46(1):57. https://doi.org/10.1007/s10792-025-03921-8
Wildner G, Gehrke M, Strauß O. (2026). Immunopathology of the outer retina: crosstalk with the immune system. Am J Ophthalmol. 2026:S0002-9394(25)00691-9. https://doi.org/10.1016/j.ajo.2025.12.032
Yazğan Y, Keleş ÖF, Bayir MH, et al. (2025). Selenium Reduces Cadmium-Induced Cardiotoxicity by Modulating Oxidative Stress and the ROS/PARP-1/TRPM2 Signalling Pathway in Rats. Toxics. 13(8):611. https://doi.org/10.3390/toxics13080611
Zhu T, Zhao Y, Hu H, et al. (2019). TRPM2 channel regulates cytokines production in astrocytes and aggravates brain disorder during lipopolysaccharide-induced endotoxin sepsis. Int Immunopharmacol. 75:105836. https://doi.org/10.1016/j.intimp.2019.105836
Zhu X, Wang K, Zhou F, Zhu L. (2018). Paeoniflorin attenuates atRAL induced oxidative stress, mitochondrial dysfunction and endoplasmic reticulum stress in retinal pigment epithelial cells via triggering Ca2+/CaMKII dependent activation of AMPK. Arch Pharm Res. 41(10):1009-1018. https://doi.org/10.1007/s12272-018-1059-6

Details

Primary Language

English

Subjects

Medical Physiology (Other)

Journal Section

Research Article

Authors

Anıl Selim Apa ^*
0000-0002-3580-0062
Türkiye

Publication Date

April 2, 2026

Submission Date

January 26, 2026

Acceptance Date

March 7, 2026

Published in Issue

Year 2026 Volume: 18 Number: 1

DOI

https://doi.org/10.37212/jcnos.1872386

IZ

https://izlik.org/JA77BK29AN

Cite

RIS / Bibtex

APA

Apa, A. S. (2026). Glutathione Protects Human Retinal Pigment Epithelial Cells From Lipopolysaccharide-Induced Apoptosis and Oxidative Stress by Inhibiting The TRPM2 Channel. Journal of Cellular Neuroscience and Oxidative Stress, 18(1), 1292-1301. https://doi.org/10.37212/jcnos.1872386

AMA

1.Apa AS. Glutathione Protects Human Retinal Pigment Epithelial Cells From Lipopolysaccharide-Induced Apoptosis and Oxidative Stress by Inhibiting The TRPM2 Channel. J Cell Neurosci Oxid Stress. 2026;18(1):1292-1301. doi:10.37212/jcnos.1872386

Chicago

Apa, Anıl Selim. 2026. “Glutathione Protects Human Retinal Pigment Epithelial Cells From Lipopolysaccharide-Induced Apoptosis and Oxidative Stress by Inhibiting The TRPM2 Channel”. Journal of Cellular Neuroscience and Oxidative Stress 18 (1): 1292-1301. https://doi.org/10.37212/jcnos.1872386.

EndNote

Apa AS (April 1, 2026) Glutathione Protects Human Retinal Pigment Epithelial Cells From Lipopolysaccharide-Induced Apoptosis and Oxidative Stress by Inhibiting The TRPM2 Channel. Journal of Cellular Neuroscience and Oxidative Stress 18 1 1292–1301.

IEEE

[1]A. S. Apa, “Glutathione Protects Human Retinal Pigment Epithelial Cells From Lipopolysaccharide-Induced Apoptosis and Oxidative Stress by Inhibiting The TRPM2 Channel”, J Cell Neurosci Oxid Stress, vol. 18, no. 1, pp. 1292–1301, Apr. 2026, doi: 10.37212/jcnos.1872386.

ISNAD

Apa, Anıl Selim. “Glutathione Protects Human Retinal Pigment Epithelial Cells From Lipopolysaccharide-Induced Apoptosis and Oxidative Stress by Inhibiting The TRPM2 Channel”. Journal of Cellular Neuroscience and Oxidative Stress 18/1 (April 1, 2026): 1292-1301. https://doi.org/10.37212/jcnos.1872386.

JAMA

1.Apa AS. Glutathione Protects Human Retinal Pigment Epithelial Cells From Lipopolysaccharide-Induced Apoptosis and Oxidative Stress by Inhibiting The TRPM2 Channel. J Cell Neurosci Oxid Stress. 2026;18:1292–1301.

MLA

Apa, Anıl Selim. “Glutathione Protects Human Retinal Pigment Epithelial Cells From Lipopolysaccharide-Induced Apoptosis and Oxidative Stress by Inhibiting The TRPM2 Channel”. Journal of Cellular Neuroscience and Oxidative Stress, vol. 18, no. 1, Apr. 2026, pp. 1292-01, doi:10.37212/jcnos.1872386.

Vancouver

1.Anıl Selim Apa. Glutathione Protects Human Retinal Pigment Epithelial Cells From Lipopolysaccharide-Induced Apoptosis and Oxidative Stress by Inhibiting The TRPM2 Channel. J Cell Neurosci Oxid Stress. 2026 Apr. 1;18(1):1292-301. doi:10.37212/jcnos.1872386