白芦藜醇对凋亡诱导因子介导乙醇致幼鼠脑损伤的保护作用

Resveratrol down-regulated the expression of apoptosis-inducing factor and protected the brain injury in ethanol-induced mouse model

目的 探讨白芦藜醇对乙醇致幼鼠脑损伤保护作用的分子机制。方法 建立乙醇致脑损伤模型,将24只新生雄性小鼠于生后随机分为3组,7 d龄时,按2 g/kg乙醇（20%无菌盐水溶液）皮下注射,间隔2 h后再次注射。对照组乳鼠仅注射等量生理盐水。乙醇加白芦藜醇组（简称白芦藜醇组）自第1次乙醇注射起,每天应用白芦藜醇80 mg/kg灌胃1次,共3次。乙醇皮下注射72 h后取材。通过苏木素-伊红（HE）染色观察脑皮质形态学变化,采用常规及实时定量逆转录聚合酶链反应（RT-qPCR）、免疫组织化学（IHC）法检测凋亡诱导因子（AIF）mRNA及蛋白水平的变化。结果 常规及RT-qPCR显示,乙醇组AIF mRNA相对表达量（2.374 0±0.160 5,n=3）较生理盐水组AIF mRNA相对表达量（1.634 0±0.065 9,n=3）和白芦藜醇组mRNA相对表达量（1.5060±0.164 6,n=3）显著增加,差异有统计学意义（F=34.51,P〈0.05）。IHC检测提示生理盐水组AIF未见明显表达,阳性细胞数为（12.0±3.5）个,乙醇组中AIF表达增强,阳性细胞数为（42.0±6.5）个,而白芦藜醇组中可见少量棕色物质沉积,表达阳性细胞数为[（16.0±4.2）个,乙醇组与其他两组比较,差异有统计学意义（F=33.10,P〈0.05）。结论 乙醇致小鼠脑损伤模型中,AIF表达增强,白芦藜醇可减弱乙醇致AIF的表达,提示白芦藜醇通过调节AIF表达,参与保护乙醇致脑损伤的分子过程。

Objective Tostudy the transcript and protein level of apoptosis-inducing factor （AIF） in ethanol-induced brain injury, and elucidate the inhibitory effect of resveratrol on AIF in ethanol-induced neuron injury. Methods The ethanol-induced mouse brain injury model was constructed. Twenty-four 7- day-old mice were injected subcutaneously either with ethanol （ ethanol was diluted as a 20% solution in sterile normal saline, 2 g/kg at 0 h and again at 2 h） or with normal saline. When the mice were firstly injected, the resveratrol （80 mg/kg） was given by intragastric administration, and the brain was harvested at 72 h after the last injection. The histological changes of brain tissues were observed by hematoxylin and eo- sin （HE） staining. The transcript and protein levels of AIF were detected by real-time reverse tran- scriptase-polymerase chain reaction （RT-qPCR） and IHC in different groups. Results The relative tran- script level of AIF mRNA （2. 374 0 ± 0. 160 5, n = 3 ） was enhanced in ethanol group by RT-qPCR, as compared with normal saline solution group （ 1. 634 0 ± 0. 065 9, n = 3） and resveratrol group （ 1. 506 0 ± 0. 164 6, n = 3 ）, with the difference being significant （ F = 34. 51 ,P 〈 0. 05）. Meanwhile, the yellow sub- stances were found in ethanol group and the number of positive cells was （ 12. 0 ± 3.5, n = 3 ）. Only little yellow substance was observed in normal saline group and resveratrol groups. The number of positive cells in saline solution group and resveratrol group was respectively （12. 0 ± 3.5, n = 3 ） and （16.0 ± 4. 2, n = 3）, with the difference being significant （F = 33.10, P 〈 0. 05）. Conclusion The transcript and protein level of AIF was enhanced in ethanol-induced brain injury model. Resveratrol maybe down-regulate the mRNA and protein expression of AIF and protect the brain injury in ethanol-induced mouse model.