Fig 2: Graphical representation of the miR-125a driven cell-crossing functional network. In response to inflammatory stimulation, the expression of miR-125a increases in endothelial cells. Here, miR-125a directly regulates CDH5, PTPN1, PPP1CA, and ETS-1 while CLDN5 levels are reciprocally linked to CDH5 expression. By reducing expression of ETS-1, miR-125a inhibits VE-Cadherin transcription. Via targeting PTPN1 and PPP1CA, miR-125a affects levels of phosphorylated VE-Cadherin, destabilizing adherens junctions and thus increasing paracellular permeability. In turn, monocytic expression of miR-125a is reduced upon inflammatory stimulation, leading to an induction of CCR2 expression, impacting monocyte chemotaxis.

Fig 3: MiR-125a inhibition and its impact on endothelial barrier function. (A) Expression of miR-125a in HUVEC after transfection of a miR-125a-inhibitor (“Antimir”) as measured by qRT-PCR (n=4, ***p<0.001). (B) mRNA levels of CDH5, PTPN1, PPP1CA, ETS1, CLDN5 after transfection of a miR-125a-inhibitor compared to a scramble control (n=10-11, **p<0.01, *p<0.05). (C) Endothelial permeability as measured by FITC-Albumin passage across an endothelial monolayer in basal (left) and inflammatory (right) conditions after transfection of a miR-125a-inhibitor or a scrambled control (NC). n=11, *p<0.05. (D) Impedance measurement of the endothelial monolayer after miR-125a inhibition (red) compared to scrambled control (NC, blue). n=11, *p<0.05.