Objective: To investigate the effect of interleukin-33 (IL-33) on lipopolysaccharide (LPS)-induced permeability of rat cardiac microvascular endothelial cells (RCMECs). Methods: RCMECs were cultured in vitro to be divided into control group, LPS group, IL-33 group and LPS+IL-33 group. The effect of IL-33 on the proliferation of RCMECs was detected by cell counting reagent (CCK8). Fluorescein isothiocyanate (FITC)-dextran assay was used to evaluate the permeability of RCMECs. The expression of vascular endothelial calmodulin, ras homologous gene family (Rho) member A (RhoA) and phosphorylated Rho-associated coiled-coil-containing protein kinase (p-ROCK2) proteins were tested by western blot. High-throughput sequencing and gene ontology (GO) were performed for gene expression in LPS and LPS+IL-33 groups. Results: No significant effect of IL-33 at 10-50 ng/ml on the proliferation of RCMECs was observed (P>0.05). Compared with the control group, the permeability of RCMECs (permeability coefficient ratio 1.404±0.029 vs. 1.000±0.200, P<0.05) was significantly increased in LPS group and the expression of vascular endothelial calmodulin (relative gray value 0.429 5±0.012 9 vs. 0.594 9±0.014 2, P<0.05) was down-regulated, while the permeability of monolayers (permeability coefficient ratio, 0.948±0.013, P<0.01) was decreased in LPS+IL-33 group and the expression of vascular endothelial calmodulin (relative grayscale value 0.549 1±0.012 0, P<0.005) was up-regulated compared with the LPS group. High-throughput sequencing data revealed that the differential genes downregulated in the LPS and LPS+IL-33 groups were associated with cytoskeleton and Rho signaling pathway. Compared with the control group, RhoA (relative gray value 0.211 4±0.009 9 vs. 0.135 0±0.007 6, P<0.000 1) and p-ROCK (relative gray value 0.656 3±0.013 2 vs. 0.503 6±0.036 2, P<0.000 1) protein expression was upregulated in the LPS group. When compared with LPS group, RhoA (relative gray value 0.157 7±0.010 7, P=0.000 2), p-ROCK (relative gray value 0.427 7±0.003 8, P<0.000 1) protein expression was decreased in LPS+IL-33 group. Conclusion: IL-33 may improve LPS-induced hyperpermeability of RCMECs by inhibiting RhoA and p-ROCK protein expression in Rho/Rho-associated coiled-coil-containing protein kinase signaling pathway.
目的： 探讨白细胞介素-33（IL-33）对脂多糖（LPS）诱导的大鼠心脏微血管内皮细胞（RCMECs）通透性的影响。 方法： 体外培养RCMECs，分为空白对照组、LPS组、IL-33组和LPS+IL-33组。用细胞计数试剂（CCK8）检测IL-33对RCMECs增殖的影响。异硫氰酸荧光素（FITC）-葡聚糖法检测4组单层RCMECs通透性。Western Blot检测4组RCMECs中血管内皮钙黏蛋白、Ras同源基因家族（Rho）成员A（RhoA）、磷酸化Rho相关含卷曲螺旋蛋白激酶（p-ROCK2）蛋白表达。高通量测序比较LPS组和LPS+IL-33组的差异基因表达，并对差异基因进行基因本体（GO）富集分析。 结果： 10~50 ng/ml的IL-33对RCMECs增殖无显著影响（P>0.05）。与空白对照组比，LPS组RCMECs通透性增加（相对灰度值1.404±0.029 比 1.000±0.200，P<0.05），血管内皮钙黏蛋白表达显著下调（相对灰度值0.429 5±0.012 9 比 0.594 9±0.014 2， P<0.05）；而与LPS组比，LPS+IL-33组可降低RCMECs通透性（相对灰度值0.948±0.013，P<0.01），上调血管内皮钙黏蛋白表达（相对灰度值0.549 1±0.012 0，P<0.005）。与空白对照组比，LPS组RhoA（相对灰度值0.211 4±0.009 9 比 0.135 0±0.007 6，P<0.000 1）、p-ROCK（相对灰度值0.656 3±0.013 2 比 0.503 6±0.036 2，P<0.000 1，）蛋白表达上调；与LPS组比，LPS+IL-33组RhoA（相对灰度值 0.157 7±0.010 7，P=0.000 2）、p-ROCK（相对灰度值0.427 7±0.003 8，P<0.000 1）蛋白表达降低。高通量测序发现，LPS组、LPS+IL-33组下调的差异基因与细胞骨架及Rho信号通路相关。 结论： IL-33可能通过抑制Rho/Rho相关含卷曲螺旋蛋白激酶信号通路RhoA、p-ROCK蛋白表达，改善LPS诱导的心脏微血管内皮细胞的高通透性。.