Figure 4: Protein expression of nuclear p-p65, tight junction proteins, and MMP9 activity in the ipsilateral hemisphere after recombinant MAP4K4 delivery and MAP4K4 silencing post SAH (Experiment III). (A–D) Protein levels of p-p65, ZO-1, and claudin 5. p-p65 expression levels were elevated at 24 hours, and this effect was enhanced by MAP4K4 infusion and reversed by pretreatment with MAP4K4 siRNA. ZO-1 and claudin 5 expression had the opposite trend. (E, F) Representative gelatin zymography of MMP9 expression revealed that proteinase activity rose at 24 hours after SAH, and was enhanced by MAP4K4 infusion and reversed by pretreatment with MAP4K4 siRNA. The quantified density was normalized to the sham group. Data are expressed as the mean ± SD (n = 6; one-way analysis of variance and Tukey's post hoc test).*P < 0.05, vs. sham group; #P < 0.05, vs. SAH + NS group; †P < 0.05, vs. SAH + Scr siRNA group. MAP4K4: Sterile-20-like mitogen-activated protein kinase kinase kinase kinase 4; MMP9: matrix metalloproteinase 9; SAH: subarachnoid hemorrhage; Scr: scramble.