Antioxidant pre-treatment prevents omeprazole-induced toxicity in an in vitro model of infectious gastritis

Jonathan E. Kohler, Amy L. Blass, Jingjing Liu, Kaniza Tai, David I. Soybel

Research output: Contribution to journalArticlepeer-review

19 Scopus citations


Omeprazole is a mainstay of therapy for gastroesophageal reflux disease (GERD) and gastritis, and is increasingly used as an over-the-counter remedy for dyspepsia. Omeprazole acts by selectively oxidizing thiol targets in the gastric proton pump, but it also appears to be toxic to the gastric mucosa. We hypothesized that omeprazole toxicity is due to non-specific oxidation of cell structures other than the proton pump, and tested the efficacy of antioxidants to prevent omeprazole-induced toxicity in isolated rabbit gastric glands. Toxicity was measured by uptake and converstion of calcein-AM, following three hours of exposure to omeprazole and a non-selective thiol-oxidant, monochloramine. Intracellular concentration of Zn2+ and the capacity to maintain luminal acidity were monitored using the fluorescent reporters fluozin-3 and Lysosensor DND-160, respectively. Both omeprazole and monochloramine caused marked reduction in cell viability. The toxicity of omeprazole was independent of monochloramine toxicity. The thiol reducing agent dithiothreitol protected gastric glands from injury. The oxidant scavenger Vitamin C also protected, and did not impair the anti-secretory effects of omeprazole. Thus, omeprazole toxicity appears to be oxidative and preventable with antioxidant therapy, including Vitamin C. Vitamin C may be a safe and efficacious addition to treatments requiring the use of PPIs.

Original languageEnglish (US)
Pages (from-to)786-791
Number of pages6
JournalFree Radical Biology and Medicine
Issue number5
StatePublished - Sep 2010

All Science Journal Classification (ASJC) codes

  • Biochemistry
  • Physiology (medical)


Dive into the research topics of 'Antioxidant pre-treatment prevents omeprazole-induced toxicity in an in vitro model of infectious gastritis'. Together they form a unique fingerprint.

Cite this