Fig 2: Infusion of LIMKi 3 into the medial prefrontal cortex (mPFC) produced antidepressant-like effects in the chronic social defeat stress (CSDS) model of depression. (A) Schematic timeline of the experimental procedures. (B) LIMKi 3 notably blocked the CSDS-induced depressive-like behaviors in mice, as revealed by the forced swim test (FST), tail suspension test (TST), sucrose preference test, and social interaction test (n = 10). (C) Both the (CSDS + 100 µM LIMKi 3)-treated and (CSDS + 200 µM LIMKi 3)-treated mice had significantly lower levels of pLIMK1, pLIMK2, and pCofilin in the mPFC than those of the CSDS-treated mice (n = 6). The expression of total LIMK1, LIMK2, and Cofilin in the mPFC remained unchanged among all groups (n = 6). All results are expressed as the means ± SEM; **P < .01; n.s., no significance. The comparisons were made by 2-way ANOVA followed by Bonferroni’s test.

Fig 3: Chronic stress fully increased the phosphorylation level of Cofilin in the medial prefrontal cortex (mPFC) of mice. Representative western blotting images indicate that the chronic unpredictable mild stress (CUMS)-treated (A), chronic restraint stress (CRS)-treated (B), and chronic social defeat stress (CSDS)-treated (C) mice all exhibited significantly higher level of pCofilin in the mPFC but not the hippocampus than the control mice (n = 5). The level of total Cofilin in both the mPFC and hippocampus remained unchanged among all groups (n = 5). All results are expressed as the means ± SEM; **P < .01; n.s., no significance. The comparisons were made using t test.

Fig 4: Repeated fluoxetine administration restored the promoting effects of chronic unpredictable mild stress (CUMS) on the LIMK-Cofilin signaling in the medial prefrontal cortex (mPFC) of mice. (A) Fluoxetine produced antidepressant-like actions in the CUMS model of depression, as revealed by the forced swim test (FST), tail suspension test (TST), and sucrose preference test (n = 10). (B) Representative western blotting images indicate that the (CUMS + fluoxetine)-treated mice had significantly less expression of pLIMK1, pLIMK2, and pCofilin in the mPFC than the CUMS-treated mice (n = 5). The levels of total LIMK1, LIMK2, and Cofilin in the mPFC remained unchanged among all groups (n = 5). All results are expressed as the means ± SEM; *P < .05, **P < .01; n.s., no significance. The comparisons were made by 2-way ANOVA followed by Bonferroni’s test.

Fig 5: H2O2 induces brain endothelial barrier dysfunction.Western Blot analysis of P53 and ß-actin (A), APEl/Refl and ß-actin (B), phosphorylated MLC2 (pMLC2) and MLC2 (C), phosphorylated Cofilin (pCofilin) and Cofilin (D) expression levels after treatment of hCMEC/D3 cells with either vehicle (PBS) or H2O2 (10-3, 10-4, 10-5 M) for 24 h. The blots shown are representative of 3 independent experiments. The signal intensity of the protein bands was analyzed by densitometry. Protein levels were normalized to ß-actin, unless otherwise indicated. *P<0.05, **P<0.01, ***P<0.001 vs vehicle. Means ± SEM.