title: Effect of proton pump inhibitor pantoprazole on growth and morphology of oral Lactobacillus strains.
abstract: OBJECTIVE
  Proton pump inhibitors (PPI) used to suppress acid secretion in the stomach are among the most widely prescribed medications. There is emerging evidence of proton secretion elsewhere in the aerodigestive tract, and acidic microenvironments are integral to oral flora such as Lactobacillus. The hypothesis of this study is that the growth rate and morphology of oral Lactobacillus strains are effected by PPIs.
  
  
  METHODS
  Nineteen different strains of Lactobacilli were inoculated in microtiter plates at pH of 4.5 to 6.5 and exposed to twofold dilutions of pantoprazole at a range of 2.5 mg/mL to 2.5 microg/mL. Bacterial growth was monitored, and the minimum inhibitory concentration (MIC) of the drug was determined for the strains most sensitive to pantoprazole.
  
  
  RESULTS
  In the unexposed (control) group, nine Lactobacilli strains were affected by pH changes from 6.5 to 4.5. In the group exposed to pantoprazole, 9 of the 19 Lactobacilli strains were found to have an MIC below 625 microg/mL, with L. plantarum 14917 being the most sensitive (MIC = 20 microg/mL). In some strains, such as L. s. salivarius 11741, Gram-staining revealed conformational changes in the bacteria when grown in the presence of pantoprazole.
  
  
  CONCLUSIONS
  Growth rates and morphology of oral Lactobacillus are affected by the pH of the environment. Pantoprazole at supraphysiologic doses further affects growth rates and conformation in some strains.
  
  
  CONCLUSIONS
  The balance of oral flora and upper digestive tract homeostasis may be affected by unexpected targets of PPI pharmacotherapy, with possible unanticipated consequences.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Mount Sinai School of Medicine, New York, New York 10029, USA. Kenneth.altman@mountsinai.org
authors.forename: Kenneth W
authors.initials: KW
authors.lastname: Altman
authors.forename: Vina
authors.initials: V
authors.lastname: Chhaya
authors.forename: Neal D
authors.initials: ND
authors.lastname: Hammer
authors.forename: Sylvia
authors.initials: S
authors.lastname: Pavlova
authors.forename: Benjamin J
authors.initials: BJ
authors.lastname: Vesper
authors.forename: Lin
authors.initials: L
authors.lastname: Tao
authors.forename: James A
authors.initials: JA
authors.lastname: Radosevich
mesh_terms: D053799:2-Pyridinylmethylsulfinylbenzimidazoles / Q000008:administration & dosage / Q000494:pharmacology*; D000897:Anti-Ulcer Agents / Q000008:administration & dosage / Q000494:pharmacology*; D015169:Colony Count, Microbial; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007778:Lactobacillus / Q000166:cytology / Q000187:drug effects* / Q000254:growth & development; D007779:Lactobacillus acidophilus / Q000187:drug effects; D007780:Lacticaseibacillus casei / Q000187:drug effects; D052197:Limosilactobacillus fermentum / Q000187:drug effects; D048191:Lactiplantibacillus plantarum / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D009055:Mouth / Q000382:microbiology*; D000077402:Pantoprazole; D054328:Proton Pump Inhibitors
chemical_list: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000897:Anti-Ulcer Agents; D054328:Proton Pump Inhibitors; D000077402:Pantoprazole