冰片对血脑肿瘤屏障开放程度及紧密连接蛋白表达的影响

Influence of borneol on the permeability of blood-tumor barrier and the expression of tight junction protein

目的：探讨冰片对血脑肿瘤屏障（BTB）开放程度和紧密连接蛋白表达的影响。方法建立体外BTB试验模型，分为空白对照组（培养基）、冰片低剂量组（25μg/ml）、冰片中剂量组（50μg/ml）、冰片高剂量组（100μg/ml）。采用辣根过氧化酶（HRP）流量和酶联免疫吸附法（ELISA）测定不同时间点BTB的通透性及紧密连接相关蛋白的表达。结果随着时间延长，低、中、高剂量组各时间点通透率均逐渐升高（P﹤0.01）；低、中、高剂量组10～240 min通透率高于空白组（P﹤0.01）；中、高剂量组30～180 min通透率高于低剂量组（P﹤0.05）；高剂量组10～180 min通透率高于中剂量组（P﹤0.05）；不同时间点间和不同组别间Occludin蛋白表达水平比较，差异均无统计学意义（P﹥0.05）；各组ZO-1和F-actin蛋白表达量均先降低后逐渐升高（P﹤0.05）；低剂量组30 min后，中、高剂量组60 min后蛋白表达量缓慢上升，且均至240 min时基本与给药前水平一致（P﹥0.05）；中、高剂量组在30、60 min时ZO-1和F-actin蛋白表达量最低（P﹤0.01），并存在剂量依赖趋势，即高剂量﹤中剂量﹤低剂量﹤给药前。结论冰片可以增加BTB的开放程度，从而提高化疗药物的透过率，其机制可能是通过调控紧密连接蛋白ZO-1和F-actin的表达而实现的。

Objective To explore the influence of borneol on the permeability of blood-tumor barrier （BTB） and the expression of tight junction protein. Method The intracranial tumor xenograft rat models of C6 were established and di-vided as control group （growth medium）, low-dose group （25 μg/ml）, medium-dose group （50 μg/ml） and high-dose group （100μg/ml）, treated with medium and borneol of various concentrations. The permeability of BTB and the expres-sion of tight junction protein were measured at different time points by HRP and ELISA assay. Result With time elapsed, the permeability at different time points were increased in the three groups （P〈0.01）;The permeability at 10~240 min were higher in low-dose, medium-dose and high-dose group than in control group （P〈0.01）;The permeability at 30~180 min were higher in medium-dose and high-dose group than in low-dose group （P〈0.05）; The permeability at 30~1800 min were higher in high-dose group than in medium-dose group （P〈0.05）;There were no statistically signifi-cant difference on the expression of Occludin in different groups and at different time points （P〉0.05）;The expression of ZO-1 and F-actin were decreased first and then increased （P〈0.05）;The protein expression rose slowly after 30 min in low-dose group and after 60 min in medium-dose group and high-dose group, and reached the dose level consistent with that before dosing at 240 min （P〉0.05）; The protein expression of ZO-1 and F-actin were lowest in medium-dose and high-dose group at 30 and 60 min （P〈0.01）, and a dose-dependent trend was observed, i.e., high-dose〈medium-dose〈low-dose〈before dosing. Conclusion Borneol can increase the permeability of BTB, so as to improve the permeability of chemotherapeutics, which is realized by mediating the expression of ZO-1 and F-actin.