Dose-dependent expression of claudin-5 is a modifying factor in schizophrenia.

Published

Journal Article

Schizophrenia is a neurodevelopmental disorder that affects up to 1% of the general population. Various genes show associations with schizophrenia and a very weak nominal association with the tight junction protein, claudin-5, has previously been identified. Claudin-5 is expressed in endothelial cells forming part of the blood-brain barrier (BBB). Furthermore, schizophrenia occurs in 30% of individuals with 22q11 deletion syndrome (22q11DS), a population who are haploinsufficient for the claudin-5 gene. Here, we show that a variant in the claudin-5 gene is weakly associated with schizophrenia in 22q11DS, leading to 75% less claudin-5 being expressed in endothelial cells. We also show that targeted adeno-associated virus-mediated suppression of claudin-5 in the mouse brain results in localized BBB disruption and behavioural changes. Using an inducible 'knockdown' mouse model, we further link claudin-5 suppression with psychosis through a distinct behavioural phenotype showing impairments in learning and memory, anxiety-like behaviour and sensorimotor gating. In addition, these animals develop seizures and die after 3-4 weeks of claudin-5 suppression, reinforcing the crucial role of claudin-5 in normal neurological function. Finally, we show that anti-psychotic medications dose-dependently increase claudin-5 expression in vitro and in vivo while aberrant, discontinuous expression of claudin-5 in the brains of schizophrenic patients post mortem was observed compared to age-matched controls. Together, these data suggest that BBB disruption may be a modifying factor in the development of schizophrenia and that drugs directly targeting the BBB may offer new therapeutic opportunities for treating this disorder.

Full Text

Duke Authors

Cited Authors

  • Greene, C; Kealy, J; Humphries, MM; Gong, Y; Hou, J; Hudson, N; Cassidy, LM; Martiniano, R; Shashi, V; Hooper, SR; Grant, GA; Kenna, PF; Norris, K; Callaghan, CK; Islam, MD; O'Mara, SM; Najda, Z; Campbell, SG; Pachter, JS; Thomas, J; Williams, NM; Humphries, P; Murphy, KC; Campbell, M

Published Date

  • November 2018

Published In

Volume / Issue

  • 23 / 11

Start / End Page

  • 2156 - 2166

PubMed ID

  • 28993710

Pubmed Central ID

  • 28993710

Electronic International Standard Serial Number (EISSN)

  • 1476-5578

Digital Object Identifier (DOI)

  • 10.1038/mp.2017.156

Language

  • eng

Conference Location

  • England