血脂水平与华支睾吸虫致病性的初步研究

Relationship of Clonorchis sinensis infection and high level of blood lipid

目的比较高血脂小鼠和正常血脂小鼠感染华支睾吸虫后的肝脏病理变化及炎症因子水平,以研究血脂水平对华支睾吸虫致病性的影响。方法通过向BALB/c小鼠投食高脂饲料建立高血脂小鼠模型,用相同囊蚴数感染高血脂小鼠和正常血脂小鼠,比较感染1个月后小鼠相关病理指标。通过Masson染色(Masson′s trichrome staining)判断肝胆纤维化程度,使用免疫组化和实时荧光定量PCR(qPCR)检测肝脏α-平滑肌蛋白(α-SMA)定位情况和转录水平,用流式细胞术检测小鼠脾细胞在刀豆素(ConA)刺激48 h培养上清中细胞因子表达水平。结果与正常血脂感染组小鼠相比,高血脂感染组小鼠出现较显著的肝胆管扩张、肝实质及汇管区出现大量的胶原纤维增生、小胆管增生等病变。高血脂感染组α-SMA转录水平升高,并在肝脏组织汇管区及增生的纤维间隔内表达。高脂感染组脾细胞培养上清中白介素6(IL-6)和IL-10表达水平比正常血脂小鼠高(P<0.05),高脂感染组IFN-γ水平比高脂未感染组低(P<0.05)。结论高血脂可能使华支睾吸虫感染所致的肝脏胶原纤维增生、胆管扩张更明显,血脂水平高低还可影响华支睾吸虫感染后宿主的免疫应答。

Objective To understand the differences of the severity of hepatic fibrosis and levels of related cytokines between Clonorchis sinensis （C.sinensis） infected hyperlipidemia mice and mice with basal diet. Methods BALB/c mice with hyperlipidemia were obtained by fed with hyperlipidemic diet, and then hyperlipidemia BALB/e mice and normal mice were infected with equal number of metacereariae. One month after infection, pathologic changes of the liver tissues from mice with different treatments were observed by Masson＇s trichrome staining. The transcription level of α-SMA in liver tissue was analyzed by real-time quantitative polymerase chain reaction. The distribution of α-SMA was detected by immunoehemistry. The levels of inflammatory eytokines in the supernatant of ConA stimulated spleen ceils isolated from mice with different treatment were detected by flow cytometry. Results Compared with control groups, obvious dilated hepatobiliary ducts and ductular proliferation were observed in hyperlipidemia mice with C. sinensis infection. Collagen was highly expressed in liver parenchyma and around the portal area. The transcription level of α-SMA was higher in hyperlipidemia mice with C. sinensis infection than that of the control, and α-SMA was highly expressed around portal area. The levels of IL-6 and IL-10 in the supernatant of treated spleen cells isolated from hyperlipidemia mice with C. sinensis infection were higher （P〈0.05） than that of control. Higher IFN-γ level were observed in hyperlipidemia mice without infection compared with the negative control （P〈 0.05）. Conclusion The results suggested that the pathologic changes in liver induced by the infection of C. sinensis might get worse under hyperlipidemia. The immune response type after C. sinensis infection could be affected by blood lipid.