Overview
Barrett’s esophagus is a condition in which the normal flat, squamous lining of the lower esophagus is replaced by a columnar-type lining that more closely resembles intestinal or gastric tissue. It usually develops in the setting of chronic gastroesophageal reflux disease, or GERD, when repeated exposure to stomach acid and bile irritates the esophageal lining over time. This new study shows that a loss of epithelial sulfide signaling is not just a bystander effect of inflammation and reflux, but a central event that reshapes the redox environment of the esophagus and helps drive the metaplastic changes seen in Barrett’s esophagus.
The investigators focused on protein persulfidation, often abbreviated PSSH, a reversible chemical modification in which hydrogen sulfide-related sulfur groups are added to protein cysteine residues. This modification can protect proteins from oxidative damage and help regulate enzyme activity. In healthy tissue, persulfidation is part of the normal redox balance. In reflux-injured tissue, however, oxidative stress and increased sulfide breakdown appear to reduce this protective system, setting off a chain of changes that promote disease progression.
Why this matters
Barrett’s esophagus is clinically important because it is the main known precursor lesion for esophageal adenocarcinoma, a cancer with a poor prognosis when discovered late. Not every patient with Barrett’s develops cancer, but identifying the mechanisms that trigger the metaplastic switch and sustain abnormal growth is essential for prevention, early detection, and targeted therapy.
Until now, the redox biology behind Barrett’s esophagus had been incompletely understood. Oxidative stress has long been recognized as part of GERD-related injury, but the specific downstream molecular changes were less clear. This work adds a new layer of understanding by showing that pathology-driven sulfide loss changes the protein redox landscape, including proteins linked to inflammation, metabolism, and prostaglandin signaling.
Study design
The researchers used a combined approach involving two patient cohorts, proteomics, chemoproteomics, and experimental models. In human tissue samples, they compared healthy squamous epithelium, GERD-exposed epithelium, and Barrett’s metaplastic epithelium. They mapped both the total protein profile and the persulfidated protein profile to identify how disease altered the esophageal proteome.
To test causality, they also used in vitro and in vivo models of chronic GERD and Barrett’s esophagus. In these experimental systems, they manipulated hydrogen sulfide levels genetically and pharmacologically. This allowed the team to see whether restoring sulfide signaling could reduce injury or whether sulfide depletion would worsen metaplasia.
In parallel, mechanistic experiments were performed using tissue biopsies and recombinant human proteins to examine how specific enzymes behave under persulfidation and oxidation.
Main findings
A major finding was that GERD-related oxidative stress reduces hydrogen sulfide availability and increases its catabolism in the esophageal epithelium. This early sulfide loss leads to remodeling of the persulfidation proteome even before full metaplastic transformation is established. As the disease progresses into Barrett’s esophagus, these changes expand dramatically.
In clinical samples, more than 1,300 proteins showed altered persulfidation patterns, suggesting a broad and biologically meaningful reprogramming of the epithelial redox network. Many of these proteins are involved in antioxidant defense, cellular metabolism, protein quality control, and inflammatory signaling. The scale of these changes also suggests that persulfidation signatures may eventually serve as biomarkers for disease state or progression risk.
Another key discovery concerned prostaglandin E2, commonly called PGE2. PGE2 is a lipid mediator known to promote inflammation, tissue remodeling, and neoplastic progression. It has been implicated for years as a driver of Barrett’s esophagus development and advancement. However, the reason PGE2 accumulates in this setting has not been fully explained.
This study found that sulfide loss alters the persulfidation state of enzymes responsible for PGE2 breakdown. In particular, 15-hydroxyprostaglandin dehydrogenase, or PGDH, which normally helps inactivate PGE2, is regulated by persulfidation. When PGDH becomes persulfidated, its activity is reversibly suppressed. That means the enzyme is protected rather than permanently destroyed, and it can recover when redox conditions improve. By contrast, irreversible oxidation can lead to more lasting loss of function.
This distinction is important because it identifies a mechanism by which reflux-related oxidative injury can raise PGE2 levels and promote metaplasia, while also pointing to a potentially reversible therapeutic target.
Mechanistic interpretation
The findings support a model in which chronic reflux causes oxidative stress and disrupts the normal hydrogen sulfide-dependent redox balance of the esophageal epithelium. As sulfide levels fall and its breakdown increases, the protective persulfidation landscape is remodeled. Some proteins lose a shield against oxidative damage, while others change activity in ways that favor inflammation and metaplastic reprogramming.
In this model, the epithelium does not simply respond passively to acid injury. Instead, it undergoes an active biochemical reprogramming that changes how cells sense stress, process lipids, regulate enzymes, and maintain tissue identity. The observed changes in PGDH and PGE2 metabolism likely contribute to a microenvironment that encourages Barrett-like transformation.
The fact that H2S donors reversed some of these effects in experimental models further strengthens the argument that sulfide loss is not merely a marker of disease but a driver of it.
Clinical implications
This work may influence future approaches to the prevention and treatment of Barrett’s esophagus in several ways.
First, it highlights hydrogen sulfide metabolism as a potential therapeutic axis. Drugs or interventions that restore epithelial sulfide balance might help reduce oxidative damage and slow the metaplastic process. This does not mean H2S itself should be given broadly in clinical practice, since dosing, delivery, and safety need careful study, but it does open a new pathway for drug development.
Second, the altered persulfidation patterns may provide candidate biomarkers. If specific persulfidated proteins can be detected reliably in biopsies or perhaps in less invasive samples, they might help stratify patients with GERD who are at higher risk of developing Barrett’s esophagus or progressing to dysplasia.
Third, the study reinforces the importance of early and effective control of reflux. Standard GERD management, including proton pump inhibitors, lifestyle changes, and in selected cases anti-reflux procedures, remains essential. Reducing chronic mucosal injury may help prevent the molecular cascade that leads to metaplasia.
Fourth, the findings may help explain why anti-inflammatory and redox-targeted strategies have been of interest in Barrett’s esophagus prevention. By identifying a specific enzymatic pathway involving PGDH and PGE2, the study provides a more precise mechanistic framework for future intervention.
How this fits with current care
At present, Barrett’s esophagus is managed through a combination of acid suppression, endoscopic surveillance, and treatment of visible dysplasia when present. Patients with nondysplastic Barrett’s are usually followed with periodic endoscopy, while those with dysplasia may undergo endoscopic eradication therapy such as radiofrequency ablation or endoscopic mucosal resection.
This new research does not replace existing care. Instead, it deepens the biological understanding behind why reflux injury can lead to Barrett’s in some patients and not others. Over time, if the persulfidation pathway proves clinically useful, it could complement current surveillance strategies by helping identify patients who need closer monitoring or preventive intervention.
Limitations and future directions
As with any translational study, several questions remain. The exact sequence of events linking reflux injury, sulfide loss, persulfidation remodeling, and metaplasia still needs to be dissected further. Human tissue studies are powerful, but they do not prove every causal step on their own. Experimental models help, but they may not fully capture the complexity of chronic human GERD.
Future research will need to determine which persulfidated proteins are most important for disease initiation, which changes are merely associated with disease, and whether restoring sulfide signaling can safely prevent Barrett’s esophagus in high-risk patients. It will also be important to explore whether similar redox changes occur in patients with different reflux patterns, obesity, smoking exposure, or other known risk factors.
Another important direction is biomarker validation. A panel of persulfidation-related markers could potentially improve risk prediction, but only if it performs well across diverse patient groups and testing platforms.
Take-home message
This study identifies epithelial sulfide loss and persulfidation remodeling as central events in the development of Barrett’s esophagus. Rather than viewing reflux injury only as chemical irritation, the research shows that chronic GERD can reprogram the esophageal redox proteome, alter key enzymes such as PGDH, increase PGE2 accumulation, and promote metaplastic transformation.
The work offers a new mechanistic explanation for Barrett’s esophagus and suggests that restoring sulfide balance, protecting redox-sensitive proteins, or targeting PGE2 metabolism may become future strategies for prevention and treatment. For now, the study mainly advances scientific understanding, but its translational potential is significant.
