Liu Qi, Xu Liming, Ren Guangming, Zhao Jingzhuang, Shao Yizhi, Lu Tongyan
Key Laboratory of Aquatic Animal Diseases and Immune Technology of Heilongjiang Province, Department of Aquatic Animal Diseases and Control, Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin 150070, China.
Life Sci. 2023 May 15;321:121591. doi: 10.1016/j.lfs.2023.121591. Epub 2023 Mar 17.
In the past decades, Txnrd3 as selenoprotein is considered to be highly expressed in testis and participate in sperm mature; however its role in liver diseases needs further study. Iron is essential for humans and animals, while its overload could damage to multiple organs. However, role of Txnrd3 and iron in cirrhosis is still unclear.
Forty 8-week-old wild-type and forty Txnrd3-/- mice were selected to build liver cirrhosis model using Thiacetamide solution, deposition of iron in liver was observed via Prussian blue staining. Txnrd3 overexpression/knockdown model in vitro was constructed based on cell transfection techniques in AML12 cells, expression abundance of ferroptosis pathway genes within cells and tissues were determined by qRT-PCR and Western Blot.
Results showed that Txnrd3-/- mice developed more pronounced liver damage, accompanied by reduced GPX4 expression and iron deposition. A significant decrease in the expression abundance of GPX4 was also detected in Txnrd3 knock-down AML12 cells. In summary, Txnrd3 knockdown could result in iron overload and ferroptosis pathway activation within liver tissues and hepatocytes, ultimately lead to the occurrence of liver injury and cirrhosis.
These results will provide biological markers for early diagnosis during cirrhosis and lay a theoretical basis for clinical therapy.
在过去几十年中，硫氧还蛋白还原酶3（Txnrd3）作为一种硒蛋白，被认为在睾丸中高表达并参与精子成熟；然而，其在肝脏疾病中的作用尚需进一步研究。铁对人类和动物至关重要，但其过载会损害多个器官。然而，Txnrd3与铁在肝硬化中的作用仍不清楚。
选取40只8周龄野生型小鼠和40只Txnrd3基因敲除小鼠，用硫代乙酰胺溶液建立肝硬化模型，通过普鲁士蓝染色观察肝脏中铁的沉积情况。基于AML12细胞的细胞转染技术构建体外Txnrd3过表达/敲低模型，采用qRT-PCR和蛋白质免疫印迹法检测细胞和组织中 ferroptosis通路基因的表达丰度。
结果显示，Txnrd3基因敲除小鼠肝脏损伤更为明显，伴有谷胱甘肽过氧化物酶4（GPX4）表达降低和铁沉积。在Txnrd3敲低的AML12细胞中也检测到GPX4表达丰度显著降低。总之，敲低Txnrd3可导致肝脏组织和肝细胞内铁过载和ferroptosis通路激活，最终导致肝损伤和肝硬化的发生。
这些结果将为肝硬化早期诊断提供生物学标志物，并为临床治疗奠定理论基础。
