Skip to main content
Article thumbnail
Location of Repository

Hydrophilic bile acids protect human blood-brain barrier endothelial cells from disruption by unconjugated bilirubin: an in vitro study

By Inês ePalmela, Leonor eCorreia, Rui eSilva, Rui eSilva, Hiroyuki eSasaki, Kwang Sik Kim, Dora eBrites, Dora eBrites and Maria A Brito and Maria A Brito


Ursodeoxycholic acid and its main conjugate glycoursodeoxycholic acid are bile acids with neuroprotective properties. Our previous studies demonstrated their anti-apoptotic, anti-inflammatory and antioxidant properties in neural cells exposed to elevated levels of unconjugated bilirubin as in severe jaundice. In a simplified model of the blood-brain barrier, formed by confluent monolayers of a cell line of human brain microvascular endothelial cells, unconjugated bilirubin has shown to induce caspase-3 activation and cell death, as well as interleukin-6 release and a loss of blood-brain barrier integrity. Here we tested the preventive and restorative effects of these bile acids regarding the disruption of blood-brain barrier properties by unconjugated bilirubin in in vitro conditions mimicking severe neonatal hyperbilirubinemia and using the same experimental blood-brain barrier model. Both bile acids reduced the apoptotic cell death induced by unconjugated bilirubin, but only glycoursodeoxycholic acid significantly counteracted caspase-3 activation. Bile acids also prevented the upregulation of interleukin-6 mRNA, whereas only ursodeoxycholic acid abrogated cytokine release. Regarding barrier integrity, only ursodeoxycholic acid abrogated unconjugated bilirubin-induced barrier permeability. Better protective effects were obtained by bile acid pre-treatment, but a strong efficacy was still observed by their addition after unconjugated bilirubin treatment. Finally, both bile acids showed ability to cross confluent monolayers of human brain microvascular endothelial cells in a time-dependent manner. Collectively, data disclose a therapeutic time-window for preventive and restorative effects of ursodeoxycholic acid and glycoursodeoxycholic acid against unconjugated bilirubin-induced blood-brain barrier disruption and damage to human brain microvascular endothelial cells

Topics: Blood-Brain Barrier, Interleukin-6, Unconjugated bilirubin, Glycoursodeoxycholic acid, Human brain microvascular endothelial cells, ursodeoxycholic acid., Neurosciences. Biological psychiatry. Neuropsychiatry, RC321-571
Publisher: Frontiers Media S.A.
Year: 2015
DOI identifier: 10.3389/fnins.2015.00080
OAI identifier:
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • (external link)
  • (external link)
  • (external link)
  • Suggested articles

    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.