角质化细胞生长因子对内毒素致大鼠急性肺损伤防护作用的研究

发布时间：2018-05-26 10:39

  本文选题：急性肺损伤 + 内毒素　； 参考：《中国人民解放军医学院》2013年博士论文

【摘要】：目的：观察角质化细胞生长因子(KGF)对大鼠急性肺损伤(ALI)模型的防护作用,观察动脉血气、肺系数、肺组织细胞标志物的变化及MicroRNA的差异表达,为KGF对ARDS/ALI防护作用的机制研究提供新的思路。 方法：本实验分为三个部分： 实验一：KGF对LPS致大鼠ALI/ARDS的干预作用。18只SD大鼠按体重随机分为A组：为正常对照组：B组：为ALI/ARDS模型组,经尾静脉按6mg/kg注射脂多糖(LPS); C组：为KGF干预组,尾静脉注射LPS前72h,经气道按5mg/kg滴注KGF。尾静脉注射LPS8h后观察各组大鼠的血气分析、肺系数和肺组织病理学变化。 实验二：KGF对LPS所致大鼠ALI/ARDS肺组织匀浆中KL-6、AQP5及ACE的影响。实验分组同实验一。通过Western Blot观察不同实验组大鼠肺组织匀浆中KL-6、水通道蛋白5(AQP5)和血管紧张素转化酶(ACE)含量的变化。 实验三：KGF对LPS所致肺损伤microRNA表达的影响。6只SD大鼠随机分为2组,每组3只。LPS组：为ALI/ARDS模型组,经尾静脉按6mg/kg注射脂多糖(LPS); KGF组：为KGF干预组,尾静脉注射LPS前72h,经气道按5mg/kg滴注KGF。尾静脉注射LPS8h后利用高通量芯片对比LPS组和KGF组大鼠肺组织中microRNA的差异表达,并通过real-time-PCR进行验证。 结果： 实验一：与A组比较,其他各组大鼠PaO2、PaO2/FiO2均有下降(P0.01),各染毒组大鼠PaCO2较A组均有升高,有极显著差异(P0.01),与B组相比,C组大鼠PaO2、PaCO2及PaO2/FiO2的改善显著(P0.01或P0.05)；B组和C组大鼠肺湿干比、肺含水量较A组显著增高(P0.01或P0.05)；光镜下观察可见B组大鼠肺组织肺泡壁高度增生肥厚,可见纤维化区域,同时又大量淋巴细胞浸润和少量红细胞浸润,C组较B组明显改善。 实验二：与A组相比,B组和C组大鼠肺组织匀浆中KL-6含量均有显著增高(P0.05),C组较之B组大鼠肺组织匀浆中KL-6含量也有明显升高,差别有统计学意义(P0.05)；与A组相比,其他各组大鼠肺组织匀浆中AQP5的含量明显下降(P0.05),与B组相比,C组大鼠肺组织匀浆中AQP5的含量有升高,但差别无统计学意义(p0.05)；与A组相比,其他各组大鼠肺组织匀浆中ACE含量均有升高,差别有统计学意义(P0.05),C组较B组大鼠肺组织匀浆ACE含量有下降,但两者之间的差异不显著(P0.05)。 实验三：芯片结果显示两组间无差异表达的miRNA,通过生物信息学预测和real-time-PCR验证发现,与LPS组相比,miR-494显著上调,miR-145和miR-146b显著下调,差别具有统计学意义(p0.01)。 结论： 1.KGF对LPS致大鼠急性肺损伤具有预防作用,可以显著增加PaO2、 PaO2/FiO2,降低PaCO2、肺湿干比和含水量,刺激AT-Ⅱ细胞增殖是KGF发挥作用的可能机制之一。 2.KGF可通过促进AT-Ⅱ细胞增殖,增加AT-Ⅰ细胞,维持肺血管内皮细胞完整性来发挥其肺损伤防护作用。 3. miR-494、miR-145和miR-146b在KGF组大鼠肺组织的表达有明显变化,这些miRNA与促进细胞增殖和抗凋亡密切相关,可能是KGF是预防和治疗LPS致肺损伤的重要靶点。
[Abstract]:Objective: To observe the protective effect of keratinocyte growth factor (KGF) on acute lung injury (ALI) model in rats, observe the changes of arterial blood gas, lung coefficient, change of lung tissue cell markers and the differential expression of MicroRNA, and provide a new idea for the mechanism of KGF for the protection of ARDS/ALI.
Methods: the experiment was divided into three parts:
Experiment 1: the intervention of KGF on LPS induced ALI/ARDS in rats.18 rats were divided into A group according to weight randomly: the normal control group: the B group: the ALI/ARDS model group, the tail vein in 6mg/kg injection of lipopolysaccharide (LPS), the C group: the tail vein was injected before the tail vein injection, and the meridian was injected into the tail vein to observe each group. Blood gas analysis, lung coefficient and pathological changes of lung tissue in rats.
Experiment two: the effect of KGF on KL-6, AQP5 and ACE in ALI/ARDS lung homogenate of rats induced by LPS. Experimental group and Experiment 1. Observe the changes of KL-6, aquaporin 5 (AQP5) and angiotensin converting enzyme (ACE) in the lung homogenate of different experimental groups by Western Blot.
Experiment three: the effect of KGF on the expression of microRNA in lung injury induced by LPS,.6 rats were randomly divided into 2 groups, each group of 3.LPS groups, ALI/ARDS model group and 6mg/kg injection of lipopolysaccharide (LPS) through 6mg/kg, KGF group: KGF intervention group, caudal vein before LPS. The differential expression of microRNA in lung tissue of rats in group LPS and KGF was verified by real-time-PCR.
Result锛，

本文编号：1936921