Abstract

Seliciclib displayed limited brain exposure in vivo in adult rats with mature blood-brain barrier (BBB). Selicilib was shown to be a specific substrate of human ABCB1 in vitro.To demonstrate that ABCB1/Abcb1 can limit brain exposure in vivo in mice we are showing that seliciclib is a substrate of mouse Abcb1a, the murine ABCB1 ortholog expressed in the BBB as LLC-PK-Abcb1a cells displayed an efflux ratio (ER) of 15.31±3.54 versus an ER of 1.44±0.10 in LLC-PK1-mock cells. Additionally, in the presence of LY335979, an ABCB1/Abcb1a specific inhibitor, the observed ER for seliciclib in the LLC-PK1-mMdr1a cells decreased to 1.05±0.25. To demonstrate in vivo relevance of seliciclib transport by Abcb1a mouse brain microdialysis experiments were carried out that showed that the AUCbrain/AUCblood ratio of 0.143 in anesthetized mice increased about two-fold to 0.279 in the presence of PSC833 another ABCB1/Abcb1a specific inhibitor. PSC833 also increased the brain exposure (AUCbrain) of seliciclib close to 2-fold (136 vs 242) in awake mice.In sum, Abcb1a significantly decreases seliciclib permeability in vitro and is partly responsible for limited brain exposure of seliciclib in vivo in mice.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.