Faculty of Medicine and Health Sciences, University of Applied Sciences in Tarnow, Mickiewicza 8, 33-100 Tarnów, Poland.
Ludwik Rydygier Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, Jagiellońska 13/15, 85-067 Bydgoszcz, Poland.
Int J Mol Sci. 2024 Sep 28;25(19):10476. doi: 10.3390/ijms251910476.
The role of autophagy goes far beyond the elimination of damaged cellular components and the quality control of proteins. It also cleanses cells from inclusions, including pathogenic viruses, and provides energy-forming components. The liver, which is an organ with increased metabolism, is made up of cells that are particularly vulnerable to damage. Therefore, detoxification of liver cells in the process of autophagy has become a very important issue clinically. The aim of this study was an immunohistochemical evaluation of proteins activated in rat liver cells at different stages of hyperbaric autophagy. The rats used for the study were randomly divided into six equivalent groups-three control groups and three experimental groups. Animals from the experimental groups were subjected to hyperbaric treatment in a hyperbaric chamber, with a pressure of 1.6 ATA for 120 min. They breathed atmospheric air. Rats were decapitated within 5 or 10 days after removal from the chamber. Immunohistochemical reactions with beclin 1, LC3B, RAB7, and HSC73 proteins were carried out on preparations made from liver slices. A three-step labeled streptavidin-biotin detection method of paraffin blocks (LSAB three-step) was used for immunohistochemical research. The results were evaluated using computer programs for morphometric analysis of microscopic images by calculating the mean surface areas occupied by a positive immunohistochemical reaction in individual groups for all antibodies tested. Increased closure of substrates in the autophagosome (beclin 1) induced late endosome transport and accelerated autophagosome maturation process (RAB7). Furthermore, a larger number of autophagosomes (LC3B) was observed in liver cells immediately after the cessation of hyperbaric activity; however, this decreased after 5 days. During this time, chaperone-mediated autophagy (HSC73) was observed on a larger scale. This means that increased macroautophagy induced by hyperbaric treatment weakens with time that has elapsed since the cessation of high pressure, whereas similarly induced chaperone-mediated autophagy intensifies over time.
自噬的作用远不止于清除受损的细胞成分和蛋白质的质量控制。它还可以清除包括致病性病毒在内的包含物，并提供能量形成成分。肝脏是一个新陈代谢旺盛的器官，由特别容易受损的细胞组成。因此，自噬过程中肝细胞的解毒已成为临床上非常重要的问题。本研究的目的是通过免疫组织化学方法评价不同高压自噬阶段大鼠肝细胞中激活的蛋白质。用于研究的大鼠被随机分为六组相等的三组对照组和三组实验组。实验组的动物在高压舱中接受高压治疗，压力为 1.6ATA 持续 120 分钟。它们呼吸空气。从高压室取出后 5 或 10 天内处死大鼠。用肝切片制备物进行 beclin 1、LC3B、RAB7 和 HSC73 蛋白的免疫组织化学反应。使用三步标记链霉亲和素-生物素检测法（LSAB 三步法）对石蜡块进行免疫组织化学研究。使用计算机程序对各组的阳性免疫组织化学反应的平均表面积进行形态计量分析，对结果进行评估。自噬体（beclin 1）的底物闭合增加诱导晚期内体运输并加速自噬体成熟过程（RAB7）。此外，在高压活动停止后，立即观察到更多的自噬体（LC3B）在肝细胞中；然而，这在 5 天后减少了。在此期间，观察到更大规模的伴侣介导自噬（HSC73）。这意味着高压处理诱导的巨自噬随着高压停止后时间的推移而减弱，而类似诱导的伴侣介导自噬随着时间的推移而增强。
