title: Chlorhexidine inhibits L1 cell adhesion molecule-mediated neurite outgrowth in vitro.
abstract: BACKGROUND
  Chlorhexidine is a skin disinfectant that reduces skin and mucous membrane bacterial colonization and inhibits organism growth. Despite numerous studies assessing chlorhexidine safety in term infants, residual concerns have limited its use in hospitalized neonates, especially low-birth-weight preterm infants. The aim of this study was to assess the potential neurotoxicity of chlorhexidine on the developing central nervous system using a well-established in vitro model of neurite outgrowth that includes laminin and L1 cell adhesion molecule (L1) as neurite outgrowth-promoting substrates.
  
  
  METHODS
  Cerebellar granule neurons are plated on poly L-lysine, L1, or laminin. Chlorhexidine, hexachlorophene, or their excipients are added to the media. Neurons are grown for 24 h, fixed, and neurite length is measured.
  
  
  RESULTS
  Chlorhexidine significantly reduced the length of neurites grown on L1 but not on laminin. Chlorhexidine concentrations as low as 125 ng/ml statistically significantly reduced neurite length on L1. Hexachlorophene did not affect neurite length.
  
  
  CONCLUSIONS
  Chlorhexidine at concentrations detected in the blood following topical applications in preterm infants specifically inhibited L1-mediated neurite outgrowth of cerebellar granule neurons. It is now vital to determine whether the blood-brain barrier is permeable to chlorhexidine in preterm infants.
authors.affiliation: Department of Pediatrics, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Aaron M
authors.initials: AM
authors.lastname: Milstone
authors.affiliation: Department of Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland.
authors.forename: Penny
authors.initials: P
authors.lastname: Bamford
authors.affiliation: Department of Pediatrics, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Susan W
authors.initials: SW
authors.lastname: Aucott
authors.affiliation: Department of Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland.
authors.forename: Ningfeng
authors.initials: N
authors.lastname: Tang
authors.affiliation: Department of Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland.
authors.forename: Kimberly R
authors.initials: KR
authors.lastname: White
authors.affiliation: Department of Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland.
authors.forename: Cynthia F
authors.initials: CF
authors.lastname: Bearer
mesh_terms: D002710:Chlorhexidine / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D007231:Infant, Newborn; D039842:Neural Cell Adhesion Molecule L1 / Q000502:physiology*; D016501:Neurites / Q000187:drug effects*
chemical_list: D039842:Neural Cell Adhesion Molecule L1; D002710:Chlorhexidine