Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China.
Xin Hua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 202155, China.
World J Gastroenterol. 2020 Nov 7;26(41):6346-6360. doi: 10.3748/wjg.v26.i41.6346.
Chronic liver injury (CLI) is now a worldwide disease. However, there is no effective treatment. Pyroptosis plays an essential role in CLI. Dihydromyricetin (DHM) resists oxidation and protects the liver. We hypothesize that the beneficial effect of DHM on CLI is related to its effect on the expression of pyroptosis-related molecules. Therefore, we studied the influence of DHM on CLI and pyroptosis.
To study the role of pyroptosis in the pathogenesis of CLI and the therapeutic mechanism of DHM.
Thirty-two mice were randomly divided into four groups: The control group was injected with olive oil, the carbon tetrachloride (CCl) group was injected with CCl, the vehicle group was injected with hydroxypropyl-β-cyclodextrin while injecting CCl and the DHM group was injected with DHM while injecting CCl. After four weeks of treatment, liver tissues from the mice were stained with hematoxylin and eosin, and oil red O. Blood was collected from the angular vein for serological analysis. The severity of CLI was estimated. Some liver tissue was sampled for immunohistochemistry, Western blotting and quantitative reverse transcription PCR to observe the changes in pyroptosis-related molecules.
Serum total cholesterol, low density lipoprotein, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the CCl group were higher than those in the control group, and serum total cholesterol, low density lipoprotein, AST and ALT in the DHM group were lower than those in the vehicle group. Hematoxylin and eosin and oil red O staining showed that there were more lipid droplets in the CCl group than in the control group, and there were fewer lipid droplets in the DHM group than in the vehicle group. Western blotting showed that the expression of the pyroptosis-related molecules caspase-1, NOD-, LRR- and pyrin domain-containing 3 (NLRP3) and gasdermin D (GSDMD)-N in the CCl group was higher than that in the control group, while expression of these proteins in the DHM group was lower than that in the vehicle group. Quantitative reverse transcription PCR results showed that the expression of the pyroptosis-related genes caspase-1, NLRP3, GSDMD and interleukin-1β (IL-1β) in the CCl group was higher than that in the control group, while there was no significant change in NLRP3 and caspase-1 expression in the DHM group compared with that in the vehicle group, and the expression of GSDMD and IL-1β was decreased.
DHM improves CCl-induced CLI and regulates the pyroptosis pathway in hepatocytes. DHM may be a potential therapeutic agent for CLI.
慢性肝损伤（CLI）现在是一种全球性疾病。然而，目前还没有有效的治疗方法。细胞焦亡在 CLI 中起着重要作用。二氢杨梅素（DHM）具有抗氧化和保护肝脏的作用。我们假设 DHM 对 CLI 的有益作用与其对细胞焦亡相关分子表达的影响有关。因此，我们研究了 DHM 对 CLI 和细胞焦亡的影响。
研究细胞焦亡在 CLI 发病机制中的作用及 DHM 的治疗机制。
将 32 只小鼠随机分为四组：对照组注射橄榄油，CCl 组注射 CCl，载体组注射羟丙基-β-环糊精的同时注射 CCl，DHM 组注射 CCl 的同时注射 DHM。治疗 4 周后，对小鼠的肝组织进行苏木精和伊红染色、油红 O 染色。从角静脉采血进行血清学分析。评估 CLI 的严重程度。采集部分肝组织进行免疫组织化学、Western blot 和定量逆转录 PCR，观察细胞焦亡相关分子的变化。
CCl 组血清总胆固醇、低密度脂蛋白、天冬氨酸氨基转移酶（AST）和丙氨酸氨基转移酶（ALT）高于对照组，DHM 组血清总胆固醇、低密度脂蛋白、AST 和 ALT 低于载体组。苏木精和伊红染色、油红 O 染色显示，CCl 组的脂质滴多于对照组，DHM 组的脂质滴少于载体组。Western blot 显示，CCl 组细胞焦亡相关分子半胱氨酸天冬氨酸蛋白酶-1（caspase-1）、核苷酸结合寡聚化结构域样受体热蛋白结构域相关蛋白 3（NLRP3）和 Gasdermin D（GSDMD）-N 的表达高于对照组，DHM 组的表达低于载体组。定量逆转录 PCR 结果显示，CCl 组细胞焦亡相关基因 caspase-1、NLRP3、GSDMD 和白细胞介素-1β（IL-1β）的表达高于对照组，DHM 组 NLRP3 和 caspase-1 的表达与载体组相比无明显变化，GSDMD 和 IL-1β 的表达下降。
DHM 改善了 CCl 诱导的 CLI，并调节了肝细胞中的细胞焦亡途径。DHM 可能是 CLI 的一种潜在治疗药物。
