摘要
目的电镜下动态观察人芽囊原虫感染大鼠盲肠超微结构损伤,并探索其可能的损伤机制。方法30只SD大鼠随机分为:感染后1周组、3周组、6周组、9周组及对照组,每组6只。以108个/mL密度的人芽囊原虫滋养体经口感染各实验组大鼠,对照组经口灌胃等体积磷酸缓冲液(PBS)。于感染后不同时间点取各组大鼠盲肠组织,利用透射电镜观察其结构变化,并采用qPCR检测盲肠组织中8-羟基鸟嘌呤DNA糖苷酶(OGG1)、脱嘌呤/脱嘧啶核酸内切酶1(Apex1)、信号传导与转录激活因子(Stat3)、蛋白酪氨酸激酶(Src)及紧密连接胞质蛋白(ZO⁃1)的mRNA表达水平。结果透射电镜下观察各组大鼠盲肠肠上皮细胞的超微结构,可见线粒体的形态改变最为明显:对照组中可见线粒体形态呈规则圆形,超微结构正常;1周组中可见线粒体明显肿胀,线粒体嵴弯曲或消失,损伤与其他感染组相比最为严重;3周组中线粒体的肿胀程度较一周组线粒体肿胀程度稍轻;6周组中仅部分线粒体出现肿胀变形,且病变程度明显减轻;9周组中出现异常形态的线粒体最少,且仅见轻微变形,损伤最轻。进一步采用qPCR检查线粒体损伤相关分子的表达,结果显示:与对照组相比,OGG1、Apex1及Stat3的mRNA表达于感染后1周和3周显著升高,差异有统计学意义(P<0.05),其中1周升高最为明显,而感染后6周和9周时表达差异无统计学意义(P>0.05);Src于感染后1周显著升高(P<0.05),之后随着感染时间的延长表达量逐渐降低;ZO⁃1的表达于感染后第1周和第3周较对照组显著下降(P<0.05),而6周和9周表达差异无统计学意义(P>0.05)。结论人芽囊原虫感染可导致大鼠盲肠上皮超微结构损伤,且急性感染期损伤程度最为严重,其损伤机制可能与线粒体损伤有关。
Objective To observe the ultrastructural damage in cecum of rats infected by Blastocystis hominis under electron microscope and explore the possible mechanism of the damage.Methods Thirty male Sprague⁃Dawley rats were randomly divided into five groups,with six rats each:1 week post⁃infection(p.i),3 weeks p.i,6 weeks p.i,9 weeks p.i and uninfected control(NC).Rats in each infection group were orally infected with Blastocystis hominis trophozoites with a density of 108/mL,while rats in NC group were orally gavage with phosphate buffered saline(PBS)of equal volume.At different weeks p.i,these tissues were sectioned and the structure change were observed by transmission electron microscope,and the expression levels of 8⁃Oxoguanine DNA glycosylase(OGG1),de purine/depyrimidine endonuclease(Apex1),signal transducer and activator of transcription(Stat3),protein tyrosine kinase(Src)and tight junction protein(ZO⁃1)in the cecums were detected by qPCR.Results The ultrastructure of intestinal epithelial cells in the cecum of rats in each group was observed under transmission electron microscopy.The morphological changes of mitochondria were the most obvious.In NC group,mitochondria showed regular round shape and normal ultrastructure.While at 1 week p.i,the mitochondria were obviously swollen,the mitochondrial cristae were curved or disappeared,and the damage was the most serious compared to other infection groups.The degree of mitochondrial swelling at 3 weeks p.i was slightly lighter than that at 1 week p.i.At 6 weeks p.i,only some mitochondria showed swelling and deformation,and the lesion was significantly reduced.At 9 weeks p.i,the number of mitochondria with abnormal morphology was the least,and only slight deformation was observed,showing the least damage.Further,qPCR was used to detect the expressions of mitochondrial damage⁃related molecules.The results showed the expressions of OGG1,Apex1 and Stat3 were significantly increased both at 1 and 3 weeks p.i compared to NC group(P<0.05),with the more significant
作者
裴培
辛致炜
廖德君
卢韵宇
刘静
薛飒
刘登宇
傅晓茵
PEI Pei;SHIN Jyh⁃wei;LIAO De⁃jun;LU Yun⁃yu;LIU Jing;XUE Sa;LIU Deng⁃yu;FU Xiao⁃yin(Department of Parasitology,School of Preclinical Medicine,Guangxi Medical University,Nanning,Guangxi 530021;Department of Parasitology,Institute of Microbiology and Immunology,College of Medicine,National Cheng Kung University,Tainan,Taiwan 70101;Department of Parasitology,Qiannan Medical College for Nationalities,Duyun,Guizhou 558000,China)
出处
《热带医学杂志》
CAS
2020年第5期596-602,共7页
Journal of Tropical Medicine
基金
国家自然科学基金项目(81360256)
广西自然科学基金面上项目(2017GXNSFAA198124)。
关键词
人芽囊原虫
盲肠上皮细胞
线粒体氧化损伤
透射电子显微镜
Blastocystis hominis
Cecum epithelial cells
Mitochondrial oxidative damage
Transmission electron microscope
