黄芩苷调控自噬保护肠黏膜屏障干预肠道急性移植物抗宿主病

文题释义：移植物抗宿主病：是由于移植后异体供者移植物中的T淋巴细胞，经受者发动的一系列“细胞因子风暴”刺激，显著增强了其对受者抗原的免疫反应，以受者靶细胞为目标发动细胞毒攻击，其中皮肤、肝及肠道是主要的靶目标。根据移植物抗宿主病在移植后发生的时间，如在100 d内发生者称为急性移植物抗宿主病，在100 d后发生者称为慢性移植物抗宿主病。黄芩苷：黄芩汤的君药黄芩，《神农本草经》谓可治“肠辟泄利”，性苦寒，可清肺胃胆及大肠经之湿热，黄芩苷是黄芩中提取的一种黄酮类化合物，具有抑菌、清除氧自由基等作用，减轻蛋白酶与炎性因子对组织的损害。 摘要背景：急性移植物抗宿主病是造血干细胞移植后早期最容易致死的并发症之一，如何干预急性移植物抗宿主病病程是个热点问题。目的：探讨黄芩苷调控自噬干预肠道急性移植物抗宿主病的机制。方法：⁶⁰Co照射CB6F1小鼠4 h，立即尾静脉输注Balb/c小鼠单个核细胞悬液(骨髓+脾)，建立单倍体造血干细胞移植模型。造模后当天开始模型组灌胃生理盐水，治疗组灌胃黄芩苷，剂量为30 mg/(kg·d)，共14 d。治疗后进行小鼠急性移植物抗宿主病临床评分、小肠黏膜急性移植物抗宿主病病理评级，透射电镜观察小肠黏膜自噬泡结构，流式细胞仪检测小肠黏膜上皮细胞活性氧水平，Western blot检测自噬相关蛋白LC3Ⅱ、LC3-Ⅰ、Beclin1的表达。结果与结论：①治疗组临床急性移植物抗宿主病评分、小肠黏膜病理评级明显优于模型组；②透射电镜下模型组存在自噬泡但线粒体结构毁坏严重，治疗组自噬泡增多且线粒体结构相对完整；③治疗组小鼠小肠黏膜上皮细胞活性氧水平低于模型组(P < 0.01)，治疗组LC3Ⅱ/Ⅰ、Beclin1的表达水平明显高于模型组(P < 0.01)；④结果表明，黄芩苷可以通过降低活性氧的产生，提高小肠黏膜细胞的自噬水平，保护肠黏膜屏障，进而降低移植后肠道急性移植物抗宿主病的发病率。ORCID: 0000-0002-8771-5898(崔兴) 中国组织工程研究杂志出版内容重点：干细胞；骨髓干细胞；造血干细胞；脂肪干细胞；肿瘤干细胞；胚胎干细胞；脐带脐血干细胞；干细胞诱导；干细胞分化；组织工程

Baicalin protects intestinal mucosal barrier and intervenes acute graft-versus-host disease by regulating autophagy

BACKGROUND:Acute graft-versus-host disease is one of the important complications of early death after hematopoietic stem cell transplantation.How to intervene in the course of graft-versus-host disease is a hot topic.OBJECTIVE:To explore the mechanism of baicalin regulating autophagy in the treatment of acute intestinal graft-versus-host disease.METHODS:Within 4 hours after 60Co irradiation in CB6F1 mice,mononuclear cell suspension(bone marrow+spleen)of Balb/c mice was immediately infused into the tail vein to establish haploid hematopoietic stem cell transplantation model.On the day after the establishment of the model,the rats in the model group were intragastrically given normal saline and the rats in the treatment group were intragastrically given baicalin at a dose of 30 mg/(kg d)for 14 days.After treatment,clinical evaluation of acute graft-versus-host disease was conducted in mice.Pathological grade of acute graft-versus-host disease of small intestinal mucosa was analyzed.Autophagic vesicles in small intestinal mucosa were observed by transmission electron microscopy.Levels of reactive oxygen species in intestinal epithelial cells were detected by flow cytometry.The expression levels of autophagy related proteins LC3-II,LC3-I and Beclin1 were detected by western blot assay.RESULTS AND CONCLUSION:The scores of acute graft-versus-host disease and intestinal mucosa pathology grade in the treatment group were significantly better than those in the model group.Under transmission electron microscope,there were autophagic vesicles in the model group,but the mitochondrial structure was seriously damaged.In the treatment group,there were more autophagic vesicles and the mitochondrial structure was relatively intact.The level of reactive oxygen species in small intestinal epithelial cells in the treatment group was lower than that in the model group(P<0.01).The expression level of LC3II/I and Beclin1 in the treatment group was significantly higher than that in the model group(P<0.01).The results showed that baicalin could reduce the level of reactive oxygen species,increase the autophagy level of intestinal mucosal cells,protect intestinal mucosal barrier,and reduce the incidence rate of acute graft-versus-host disease after transplantation.