2nd Department of Pathology, Semmelweis University, Üllői 93, 1091, Budapest, Hungary.
Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, 1094, Budapest, Hungary.
Pathol Oncol Res. 2020 Oct;26(4):2143-2151. doi: 10.1007/s12253-020-00799-y. Epub 2020 Mar 2.
Although the role of autophagy has been implicated in several forms of chronic hepatitis, it is still not fully understood. Active autophagy eliminates damaged molecules and organelles (such as mitochondria) by lysosomal degradation. In the present study, we aimed to examine and compare autophagy activity in chronic hepatitis C (CHC) and autoimmune hepatitis (AIH) by detecting the expression of autophagy (LC3 and p62) and mitochondrium-related (TOMM20) proteins, as well as the levels of selected microRNAs (miR-101, -155, -204 and - 224) known to be involved in the regulation of autophagy. In addition, the expression levels were related to pathohistological parameters. Liver biopsy samples, including 45 CHC and 18 AIH cases, were immunohistochemically stained for LC3, p62 and TOMM20 and the expression of miRNAs was determined using real-time PCR. We found elevated LC3 and p62 in AIH samples as compared with CHC ones, indicating an activated autophagy that is impaired in AIH as no degradation of p62 seemed to occur. Moreover, p62 showed strong correlation with necroinflammatory grades in the AIH group. The observed elevated levels of TOMM20 and p62 suggest a less efficient elimination of damaged mitochondria in AIH as opposed to CHC, in which autophagy seems to have a more active function. The level of miR-101 was increased in case of CHC as compared with AIH, however, miR-155, -204 and 224 resulted in no expressional. Furthermore, miR-224 level correlated with steatosis and miR-155 expression with fibrosis stage in CHC. In conclusion, dissimilar autophagic activity was observed in CHC and AIH, suggesting a close association between impaired autophagy and severity of necroinflammation. This impairment may not be regulated by the analyzed miRNAs. Nevertheless, miR-224 and - 155 seem to be associated with CHC progression.
尽管自噬作用在几种慢性肝炎形式中起作用已被牵涉，但它仍然没有被完全理解。活跃的自噬通过溶酶体降解消除受损的分子和细胞器（如线粒体）。在本研究中，我们旨在通过检测自噬（LC3 和 p62）和线粒体相关蛋白（TOMM20）的表达，以及已知参与自噬调节的选定 microRNAs（miR-101、-155、-204 和 -224）的水平，来检查和比较丙型肝炎（CHC）和自身免疫性肝炎（AIH）中的自噬活性。此外，表达水平与组织病理学参数有关。我们对包括 45 例 CHC 和 18 例 AIH 病例的肝活检样本进行了 LC3、p62 和 TOMM20 的免疫组织化学染色，并使用实时 PCR 确定了 microRNAs 的表达水平。我们发现与 CHC 相比，AIH 样本中 LC3 和 p62 的表达升高，表明自噬被激活，但似乎没有发生 p62 的降解，这表明 AIH 中的自噬受损。此外，p62 在 AIH 组中与坏死性炎症等级呈强相关性。观察到 TOMM20 和 p62 的升高表明 AIH 中受损线粒体的清除效率低于 CHC，在 CHC 中自噬似乎具有更活跃的功能。与 AIH 相比，CHC 中 miR-101 的水平升高，然而，miR-155、-204 和 224 的表达没有差异。此外，miR-224 水平与 CHC 中的脂肪变性相关，miR-155 表达与纤维化阶段相关。总之，在 CHC 和 AIH 中观察到不同的自噬活性，表明自噬受损与坏死性炎症的严重程度密切相关。这种损伤可能不受分析的 microRNAs 的调节。然而，miR-224 和 -155 似乎与 CHC 的进展有关。
