PI3K/Akt信号通路介导莱菔硫烷预处理对大鼠供心冷缺血再灌注损伤的影响

目的：探讨脂酰肌醇-3-激酶/蛋白激酶B（PI3K/Akt）信号通路介导莱菔硫烷（SFN）预处理对大鼠心肌冷缺血再灌注损伤（IRI）的作用，阐明其作用机制。方法：64只健康雄性SD大鼠随机分为冷IRI组、SFN组、LY（PI3K抑制剂）+冷IRI组和LY+SFN组，每组供、受体各8只。将冷藏于组氨酸-色氨酸-酮戊二酸盐液（HTK液）9 h供心移植到受体大鼠的腹腔，建立同种大鼠异体异位心脏移植模型，术后24 h取供心心肌组织，采用苏木精-伊红（HE）染色观察心肌组织形态表现，免疫组织化学法和Western blotting法检测心肌组织中丝氨酸/苏氨酸蛋白激酶，即蛋白激酶B（Akt）、磷酸化Akt（p-Akt）、Bax、B细胞淋巴瘤/白血病-2（Bcl-2）的蛋白表达水平。结果：心肌组织形态表现，冷IRI组和LY+冷IRI组大鼠心肌组织损伤最严重，SFN组心肌组织损伤最轻，LY+SFN组心肌组织损伤介于冷IRI组和SFN组之间。免疫组织化学法和Western blotting法，与冷IRI组比较，SFN组p-Akt蛋白表达水平明显升高（P < 0.05），Bcl-2蛋白表达水平升高（P < 0.05），而Bax蛋白表达水平降低（P < 0.05）；应用阻滞剂LY294002后，与LY+冷IRI组比较，LY+SFN组p-Akt蛋白表达水平差异无统计学意义（P > 0.05），但Bcl-2蛋白表达水平仍升高（P < 0.05），Bax蛋白表达水平仍降低（P < 0.05），Bcl-2/Bax比值升高（P < 0.05）。结论：SFN可能通过PI3K/Akt信号通路减轻心脏移植心肌冷IRI。

Influence of sulforaphane preconditioning in myocardial cold ischemia-reperfusion injury through PI3K/Akt signaling pathway in rats

Objective:To explore the effect of sulforaphane (SFN) preconditioning on the cold myocardial ischemia-reperfusion injury (IRI) in the rats through PI3K/Akt signaling pathway.Methods:Sixty-four health male Sprague-Dawley (SD) rats were randomly divided into cold IRI group,SFN group,LY (LY294002) + cold IRI group,and LY+SFN group (n=16).The allogeneic heterotopic heart transplantation model was established by donor heart into recipient abdomen.The myocardium tissue was taken 24 h after reperfusion for the detection of histological changes using HE staining.The expression levels of Akt,p-Akt,Bax and Bcl-2 proteins were detected by immunohistochemistry and Western boltting methods.Results:The morphological results showed that the myocardium tissue damage was serious in cold IRI group and LY+cold IRI group,it was light in SFN group;the myocardium tissue damage of the rats in SFN+ LY group was ranged between cold IRI group and SFN group.Compared with IRI group,the expression levels of p-Akt protein and Bcl-2 protein in SFN group were increased (P＜0.05),and the expression level of Bax protein was decreased (P＜0.05).After treatment of blockage LY294002,compared with LY-+-cold IRI group,the expression level of p-Akt protein in LY-+-SFN group was not statistically significant (P＞0.05),the expression level of Bcl2 protein was increased (P＜0.05),the expression levels of Bax protein was decreased),and the ratio of Bcl-2/Bax was also increased (P＜0.05).Conclusion:SFN may attenuate cold IRI of heart transplantation through PI3K/Akt signaling pathway in the rats.