缺血后处理对肝硬化大鼠肝脏缺血-再灌注损伤保护作用的免疫机制

Immunity mechanism of ischemia postconditioning in preventing from hepatic ischemia-reperfusion injury in liver cirrhotic rats

目的探讨缺血后处理(IPO)对肝硬化大鼠肝脏缺血-再灌注损伤(IRI)的保护作用及其免疫机制。方法按随机数字表法将30只肝硬化模型SD大鼠随机分为IPO组、IRI组和单纯肝切除组(肝切组),各10只。IPO组先切除40%肝脏,阻断第一肝门20 min,然后反复缺血-再灌注3次,最后持续再灌注;IRI组,切除40%肝脏,阻断第一肝门20 min后持续再灌注;肝切组切除40%肝脏。分别于术后6、24 h抽取大鼠下腔静脉血,检测ALT、AST、分化群(CD)4+、CD8+、调节性T细胞(Treg)百分率、白细胞介素(IL)-4、IL-10水平。3组比较采用单因素方差分析,两两比较采用LSD-t检验。结果恢复灌注6 h后,IPO组的ALT、AST分别为(1 623±378)、(1 993±469)U/L,IRI组相应为(2 690±549)、(3 020±577)U/L,IPO组ALT、AST明显低于IRI组(LSD-t=-4.21,-3.72;P<0.05)。恢复灌注24 h后,IPO组的ALT、AST分别为(307±76)、(555±137)U/L,IRI组相应为(518±105)、(1 050±355)U/L,IPO组ALT、AST亦明显低于IRI组(LSD-t=-4.06,-3.37;P<0.05)。恢复灌注6 h后,IPO组CD4+、CD8+、CD4+/CD8+比值、Treg、IL-4、IL-10分别为(57±5)%、(25±3)%、2.3±0.5、(8.9±0.4)%、(1.27±0.25)mg/L、(0.61±0.03)mg/L,IRI组相应为(52±6)%、(12±3)%、4.5±0.8、(7.3±0.3)%、(0.66±0.11)mg/L、(0.34±0.06)mg/L,IPO组CD8+、Treg、IL-4、IL-10较IRI组明显升高,CD4+/CD8+比值明显降低(LSD-t=7.74,6.67,5.52,9.31,-6.69;P<0.05)。结论 IPO可能通过减轻免疫损伤发挥对肝硬化大鼠肝脏IRI的保护作用。

ObjectiveTo investigate the protective effects and its mechanism of ischemia postconditioning （IPO） in hepatic ischemia-reperfusion injury （IRI） in liver cirrhotic rats.MethodsThirty liver cirrhotic Sprague-Dawley （SD） rats were randomly divided into three groups according to the random table methods： ischemia postconditioning （IPO） group, IRI group, and pure hepatectomy （PH） group with 10 rats in each group. Rats in IPO group underwent partial hepatectomy （40%）, and the first portal was occluded for 20 min, then 3 times of ischemia-reperfusion were performed, and ifnally continuous＆nbsp;reperfusion. Rats in IRI group underwent partial hepatectomy （40%）, and the ifrst portal was occluded for 20 min, then continuous reperfusion was performed. Rats in PH group underwent partial hepatectomy （40%） only. Inferior vena cava blood was collected at 6, 24 h after operation. Levels of alanine aminotransferase （ALT）, aspartate aminotransferase （AST）, proportion of cluster of differentiation （CD） 4＋, CD8＋, regulatory T cells （Treg） and levels of interleukin （IL）-4, IL-10 were tested. Comparison of three groups was conducted by one way analysis of variance and pairwise comparison by LSD-t test.ResultsAfter 6 h reperfusion, levels of ALT and AST in IPO group [（1 623±378） , （1 993±469） U/L] were signiifcantly lower than those in IRI group [（2 690±549） , （3 020±577） U/L] （LSD-t=-4.21,-3.72; P〈0.05）. After 24 h reperfusion, levels of ALT and AST in IPO group [（307±76） , （555±137） U/L] were still signiifcantly lower than those in IRI group [（518±105） , （1 050±355） U/L] （LSD-t=-4.06,-3.37;P〈0.05）. After 6 h reperfusion, proportion of CD4＋, CD8＋, CD4＋/CD8＋ ratio, Treg, and levels of IL-4, IL-10 in IPO group were （57±5） %, （25±3） %, 2.3±0.5, （8.9±0.4） %, （1.27±0.25） mg/L, （0.61±0.03） mg/L, respectively. While in IRI group, they were （52±6）%, （12±3） %, 4.5±0.8, （7.3±0.3） %, （0.66±0.11） mg/L, （0.34±0.06） mg/L, respectively. In IPO group, CD8＋, Treg, IL-4 and IL-10 increased signiifcantly, while CD4＋/CD8＋ ratio decreased signiifcantly, compared with those in IRI group （LSD-t= 7.74, 6.67, 5.52, 9.31,-6.69;P〈0.05）.ConclusionIPO can prevent from hepatic IRI injury in liver cirrhotic rats through decreasing the immune injury.