dc.contributor.advisor | Spiers, James | |
dc.contributor.author | Konieczna, Sylwia Natalia | |
dc.date.accessioned | 2021-03-23T17:15:03Z | |
dc.date.available | 2021-03-23T17:15:03Z | |
dc.date.issued | 2021 | en |
dc.date.submitted | 2021 | |
dc.identifier.citation | Konieczna, Sylwia Natalia, Role of Protein Phosphatase 2A inhibition in modulation of VE-cadherin and Claudin-5 in human brain microvascular endothelial cells and the potential reversal by small molecule activators of PP2A (SMAPs), Trinity College Dublin.School of Medicine, 2021 | en |
dc.identifier.other | Y | en |
dc.identifier.uri | http://hdl.handle.net/2262/95870 | |
dc.description | APPROVED | en |
dc.description.abstract | Protein phosphatase 2A (PP2A) is a serine/threonine phosphatase which
plays a key role in modulating signalling, metabolism and cell growth, and
is implicated in various pathologies. There is conflicting evidence
regarding the role of PP2A in regulating blood brain barrier function. This
study investigates if okadaic acid and inflammation modulate VEcadherin and claudin-5 through PP2A, and whether this can be reversed
by novel small molecule activators of PP2A as a possible therapeutic
intervention.
Human brain microvascular endothelial cells (hCMEC/d3) were exposed
to IFNg/TNFa (10ng/mL each) or okadaic acid (OA, 10 nM; PP2A inhibitor)
for 24 h. mRNA and protein abundance were determined using qPCR and
western blotting, respectively. Data were analysed using one-way ANOVA
(P < 0.05) with post hoc analysis. IFNg/TNFa decreased claudin-5 and VEcadherin mRNA expression by 68 ± 6 % and 54 ± 8 % respectively, and VEcadherin protein by 83 ± 6 %. Interestingly, OA decreased VE-cadherin
mRNA and protein expression by 80 ± 5 % and 80 ± 3 %, respectively, but
had no effect on claudin-5. PP2A activators FTY-720 (1 µM) and DBK-1154
(1 µM) did not alter the responses to OA or IFNg/TNFa. Additionally,
IFNg/TNFa decreased demethylated PP2Ac and potentially increased
phosphorylated PP2Ac. Furthermore, transfection experiments were
carried out in order to overexpress PP2Ac, SET or CIP2A in hCMEC/d3
cells, however the protocol needs to be further optimized.
In conclusion, this study has shown IFNg/TNFa and OA to differentially
modulate claudin-5 mRNA expression but to have similar effects on VEcadherin. This indicates a role for PP2A in transcriptional regulation of VEcadherin but not claudin-5. Importantly, the VE-cadherin response was
insensitive to DBK-1154. The role of PP2A in modulating junctional
proteins requires further investigation. | en |
dc.language.iso | en | en |
dc.publisher | Trinity College Dublin. School of Medicine. Discipline of Pharmacology & Therapeutics | en |
dc.rights | Y | en |
dc.subject | PP2A | en |
dc.subject | VE-cadherin | en |
dc.subject | Blood-brain barrier | en |
dc.title | Role of Protein Phosphatase 2A inhibition in modulation of VE-cadherin and Claudin-5 in human brain microvascular endothelial cells and the potential reversal by small molecule activators of PP2A (SMAPs) | en |
dc.type | Thesis | en |
dc.type.supercollection | thesis_dissertations | en |
dc.type.supercollection | refereed_publications | en |
dc.type.qualificationlevel | Masters (Research) | en |
dc.identifier.peoplefinderurl | https://tcdlocalportal.tcd.ie/pls/EnterApex/f?p=800:71:0::::P71_USERNAME:KONIECZS | en |
dc.identifier.rssinternalid | 226280 | en |
dc.rights.ecaccessrights | openAccess | |