Oxidative stress and NLRP3 inflammasome activation in eye lens pathobiology during aging

The National Eye Institute awarded the Board of Regents of the University of Nebraska, through its University of Nebraska Medical Center division, $383,750 on September 1, 2026, under the Vision Research program (CFDA 93.867) to investigate oxidative stress and NLRP3 inflammasome activation in eye lens pathobiology during aging.

The research examines molecular pathways linking reactive oxygen species amplification, dysregulation of antioxidant defenses, and inflammasome-driven inflammatory responses to age-related blinding disorders. The project uses lens epithelial cells as a model system to explore how increased transcription factor KLF9 expression suppresses antioxidant genes and triggers ROS amplification and cell damage in aging lenses, and how this adverse signaling leads to aberrant TXNIP expression and NLRP3 inflammasome activation. The research tests whether antioxidant interventions such as PRDX6 can reverse these pathological cascades.

Performance occurs in Omaha, Nebraska, with a period of performance extending through March 31, 2031.

Abstract

Despite a wealth of reports demonstrating a link between inflammatory response and age-related diseases (ards), the factors that causally link to aging pathologies are poorly understood. Recently, increasing levels of oxidative stress-driven NLRP3 inflammasome activation has been implicated as a major risk factor for aging- related diseases. The dysregulation of antioxidant pathway and reactive oxygen species (ROS) amplification in aging have now been found to exacerbate NLRP3 inflammasome activation-mediated inflammatory responses and development of age-related blinding disorders. The detailed molecular pathways underlying this adverse signaling and causes for ROS amplification and related ocular pathologies with advancing age, however, remain elusive. Recently, using eye lens/lens epithelial cells (lecs) as a model, i found that aging lecs under conditions of oxidative stress reveal a dramatic increase in transcription factor KLF9 (kruppel-like factor 9) expression, resulting in KLF9-dependent antioxidant genes suppression with ROS amplification and cell damage. However, this adverse signaling ensues in aging lenses/lecs, causing aberrant txnip (thioredoxin interacting protein) expression and NLRP3 inflammasome activation-driven aging pathologies or cell death-type are not explored. Our preliminary data using each of these factors show that: 1) increased ROS level is associated with NF-ΚB activation-dependent increased KLF9 expression in aging; 2) like oxidative stress or aging lecs, lecs overexpressing KLF9 display excessive ROS and NLRP3 inflammasome activation-evoked signaling; 3) aging lecs show increased txnip expression with reduced levels of thioredoxin (TRX1) and NRF2 (NFE2-related factor 2), a repressor of txnip; 4) in contrast to aging lecs and lecs overexpressing KLF9, these lecs when treated with an antioxidant, like PRDX6 (peroxiredoxin 6) do not show NF-ΚB/KLF9/NLRP3 inflammasome axis- mediated inflammatory signaling. Backed with these observations, the central hypothesis of this proposal is that aging/oxidative stress causes aberrant expression of KLF9 via NF-ΚB, and that subsequently results in KLF9- mediated antioxidant suppression and ROS amplification, leading to NLRP3 activation-mediated pathologies via the feed-forward vicious cycles within lens microenvironment (that are operative during aging and oxidative stress with increase txnip). Using in-vitro and in-vivo approaches, we will test our hypothesis via three specific aims: 1) explore the molecular mechanisms underlying NF-ΚB-KLF9-antioxidant axis mediated induction of NLRP3 inflammasome inflammatory pathway in aging/oxidative stress in-vitro; 2) determine that KLF9's aberrant expression alters its transcriptional reprogramming, leading to NLRP3 inflammasome activation pathway; 3) determine the mechanism(s) involved in the progression of NF-ΚB-KLF9-and NLRP3 inflammasome-mediated signaling in vivo in a mouse model of age-related cataract. Understanding the mechanisms responsible for oxidative/aging-induced NLRP3 inflammasome activation-mediated lens pathobiology will set the stage for future development of novel therapeutics aimed at damping oxidative/aging/NLRP3-associated cataract formation.