摘要
目的:阐明低分子壳聚糖(LMCTS)对四氯化碳(CCl4)诱导大鼠肝纤维化的抑制作用,探讨其对Toll样受体4(TLR4)表达的影响,为开发临床治疗肝纤维化的天然候选药物奠定基础。方法:将72只雄性Wistar大鼠随机均分空白对照组、CCl4组(模型组)、甘利欣(DG)组和50、100及150mg·kg-1 LMCTS组(低、中和高剂量组)。除空白对照组外,其余5组大鼠腹腔注射40%CCl4植物油(1.75mL·kg-1),每周2次,共8周;空白对照组大鼠腹腔注射等量100%植物油。从第9周起,DG组及LMCTS组大鼠分别灌胃给予DG和LMCTS(每天1次,共4周)。实验结束后检测各组大鼠血清中丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)和碱性磷酸酶(ALP)的活性,光镜下观察肝组织病理学改变,并采用RT-PCR和Western blotting法检测TLR4表达情况。结果:血清学指标,中和高剂量LMCTS组大鼠血清ALT、AST和ALP活性均低于模型组(P<0.05);与低剂量LMCTS组比较,中剂量LMCTS组ALP活性明显降低(P<0.05),而ALT和AST活性降低不明显(P>0.05);高剂量LMCTS组ALT、AST和ALP活性与中剂量LMCTS组比较差异有统计学意义(P<0.05)。HE染色,模型组大鼠部分肝细胞脂肪变性,有明显的炎性细胞浸润和胶原纤维增生,肝小叶破坏明显,而LMCTS组大鼠肝组织的变化有所减轻。RT-PCR和Western blotting法,与模型组比较,LMCTS组大鼠肝组织中TLR4表达水平降低(P<0.05或P<0.01),以高剂量LMCTS组最为明显,不同剂量组之间比较差异均有统计学意义(P<0.05)。结论:高剂量LMCTS具有良好的降低肝纤维化大鼠血清转氨酶活性和改善肝纤维化大鼠肝功能的作用,且此过程与TLR4表达水平降低有关。
Objective To clarify the inhibitory effect of low molecular weight chitosan（LMCTS）on hepatic fibrosis induced by carbon tetrachloride （CCl4 ）in the rats, and to investigate its effect on the expression of Toll-like receptor-4（TLR4 ）and to lay the foundation for the development of the clinical candidate drug of liver fibrosis. Methods 72 male Wistar rats were randomly divided into blank control group, CCl4 group （model group）, glycyrrhizinate （DG）group,50,100 and 150 mg·kg-1 LMCTS groups （low,middle and high doses of LMCTS groups）.In addition to blank control group,the rats in the remaining groups were given 40% CCl4-vegetable oil （1.75 mL·kg-1 ）,2 times per week for 8 weeks,by intraperitoneal injection to establish the model of rat hepatic fibrosis.And the rats in blank control group were injected with the same amount of 100% vegetable oil agent. From the ninth week, the rats in DG and LMCTS groups were given DG and LMCTS by intragastric administration, 1 time/week for 4 weeks. Then all rats were sacrificed, the activities of serum glutamic acid aminotransferase （ALT）,aspartate aminotransferase （AST）and alkaline phosphatase （ALP）were detected with ELISA kit;the pathological changes in liver tissue were observed under light microscope, and the TLR4 expressions were detected by RT-PCR and Western blotting method. Results The serum ALT, AST and ALP activities in middle and high doses of LMCTS groups were lower than those in model group （P〈0.05）.The serum ALT activity in middle dose of LMCTS group was lower than that in low dose of LMCTS group （P〈0.05）,but the activities of AST and ALP had no statistically significant change（P〉005）.There were statistically significant differences in the serum ALT, AST and ALP activities between high dose of LMCTS group and middle dose of LMCTS group （P〈0.05）.There were obvious hepatocyte steatosis,inflammatory cell infiltration,collagen fiber hyperplasia and hepatic lobule damage in the rats in model group.However,all the changes in liver tissue of the rats in LMCTS group were significantly reduced, especially in high dose group. The results of RT-PCR and Western blotting method showed that the expression of TLR4 was declined in LMCTS groups compared with model group （P〈0.05,P〈0.01）,especially in high dose of LMCTS group,and there were statistically significant differences between different doses of LMCTS groups （P〈0.05）.Conclusion High dose of LMCTS can decrease the serum transaminase activity of liver fibrosis rats and improve liver function,and this process may be related to declining the expression of TLR4 .
出处
《吉林大学学报（医学版）》
CAS
CSCD
北大核心
2014年第5期1013-1017,I0005,共6页
Journal of Jilin University：Medicine Edition
基金
吉林省科技厅科技发展计划项目资助课题(20100920)
关键词
低分子壳聚糖
四氯化碳
肝纤维化
TOLL样受体4
low molecular weight chitosan
carbon tetrachloride
hepatic fibrosis
Toll-like receptor 4
作者简介
马佳男（1992-），女，黑龙江哈尔滨市人，在读医学硕士，主要从事细胞生物学研究。
通信作者 费瑞（Tel：0431-85619473，E-mail：feirui@jlu．edu．cn）
