RGS2抑制大鼠脑出血后炎症反应的实验研究

Inhibitory effect of RGS2 on inflammation after intracerebral hemorrhage in rats

摘要:

目的：探讨G蛋白信号调节因子2（regulators of G-protein signalling，RGS2）抑制大鼠脑出血（intracerebral hemorrhage，ICH）继发的炎症反应。方法：69只大鼠分为假手术组、ICH组、阴性对照慢病毒+ICH组、RGS2过表达慢病毒+ICH组和时间窗组，前4组各组12只SD大鼠，时间窗组下设normal、ICH6h、ICH12h、ICH24h、ICH48h、ICH72h和ICH7d，每小组各3只SD大鼠。基底节注射VⅡ型胶原酶，建立大鼠ICH模型，对大鼠ICH后3 d进行神经功能评分，干湿法检测脑含水量，采用Western blot和ELISA法测定血肿周围脑组织中肿瘤坏死因子-α（tumor necrosis factor，TNF-α）和白介素-1β（interleukin-1，IL-1β）的含量，免疫荧光染色方法检测病灶周边髓过氧化物酶（myeloperoxidase，MPO）表达情况。结果：①RGS2在ICH后表达量从（0.579 2±0.019 8）开始升高，并且在术后12 h达到峰值（0.809 3±0.076 2），然后降低，术后7 d恢复正常（0.600 0±0.083 0）。②与ICH组脑含水量（0.804 7±0.003 4）和神经功能评分（11.570 0±2.070 0）相比，RGS2过表达慢病毒+ICH组在ICH术后3 d脑水肿明显减轻（0.794 0±0.001 5），神经功能评分明显改善（7.429 0±0.976 0）。③RGS2过表达慢病毒+ICH组术后3 d血肿周边TNF-α和IL-1β的表达（1.407±0.055、0.762±0.046）明显低于ICH组（1.743±0.179、0.917±0.085），RGS2过表达慢病毒+ICH组TNF-α和IL-1β的A值（32.92±1.13、32.84±1.08）低于ICH组A值（40.38±0.99、39.29±1.39）。④RGS2过表达慢病毒+ICH组大鼠病灶周边MPO的表达明显低于ICH组和阴性对照慢病毒+ICH组。结论：RGS2抑制大鼠脑出血后血肿周边区TNF-α、IL-1β和MPO表达，能减轻脑水肿，改善神经功能，抑制脑出血后的炎症反应。

Abstract:

Objective：To investigate the inhibitory effect of regulator of G-protein signaling 2（RGS2） on inflammation after intracere－bral hemorrhage（ICH） in rats. Methods：Sixty-nine SD rats were divided into sham-operation group，ICH group，negative control lentivirus+ICH group，RGS2 overexpression lentivirus+ICH group，and time window group. Twelve SD rats were assigned to each of the first four groups and three SD rats to each of subgroups under the time window group，consisting of normal，ICH6h，ICH12h，ICH24h，ICH48h，ICH72h，and ICH7d. A rat model of ICH was established by injecting type VⅡ collagenase into the basal ganglia. Neurological function was scored on 3 days after model establishment. The wet-dry weight method was used to measure brain wa－ter content. Western blot and enzyme-linked immunosorbent assay were used to determine the content of tumor necrosis factor-α（TNF-α） and interleukin-1β（IL-1β） in the brain tissue around the hematoma. The immunofluorescence staining method was used to detect the expression of myeloperoxidase（MPO） around the lesion. Results：①The expression of RGS2 increased from （0.5792±0.0198） after ICH，reached a peak level of （0.809 3±0.076 2） at 12 hours after surgery，then decreased，and returned to a normal level of （0.600 0±0.083 0） on 7 days after surgery. ②Compared with the ICH group，the RGS2 overexpression lentivirus+ICH group had a significantly reduced brain water content and a significantly improved neurological function score on 3 days after surgery（0.794 0±0.001 5 vs. 0.804 7±0.003 4；7.429 0±0.976 0 vs. 11.570 0±2.070 0）. ③The expression of TNF-α and IL-1β around the hematoma on 3 days after surgery was significantly lower in the RGS2 overexpression lentivirus+ICH group than in the ICH group（1.407±0.055 vs. 1.743±0.179；0.762±0.046 vs. 0.917±0.085）. The A values of TNF-α and IL-1β were lower in the RGS2 overexpression lentivirus+ICH group than in the ICH group（32.92±1.13 vs. 40.38±0.99；32.84±1.08 vs. 39.29±1.39）. ④The RGS2 over－expression lentivirus+ICH group had significant lower expression of MPO around the lesion than the ICH group and the negative control lentivirus+ICH group. Conclusion：RGS2 inhibits the expression of TNF-α，IL-1β，and MPO around the hematoma after ICH in rats，which can reduce brain edema，improve neurological function，and inhibit inflammation after ICH.