Microbiology Department, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Biomed Res Int. 2023 Apr 12;2023:4848643. doi: 10.1155/2023/4848643. eCollection 2023.
is a prevalent pathogenic bacterium that resides in the human stomach. Outer membrane vesicles (OMVs) are known as nanosized cargos released by , which have been proposed to have a key role in disease progression, pathogenesis, and modulation of the immune system. There are multiple evidences for the role of in extragastroduodenal illnesses especially liver-related disorders. However, the precise mechanism of extragastroduodenal pathogenesis still remains unclear. In the current study, we aimed to determine the impact of -isolated OMVs on hepatic stellate cell (HSC) activation and expression of liver fibrosis markers.
Five clinical strains with different genotype profiles were used. OMVs were isolated using ultracentrifugation and were analyzed by scanning electron microscopy (SEM) and dynamic light scattering (DLS). Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) analysis was applied to determine protein components of -derived OMVs. Cell viability of LX-2 human hepatic stellate cell line exposed to OMVs was measured by MTT assay. LX-2 cells were treated with OMVs for 24 h. The gene expression of -SMA, E-cadherin, vimentin, snail, and -catenin was analyzed using quantitative real-time PCR. The protein expression of -SMA, as a well-studied profibrotic marker, was evaluated with immunocytochemistry.
Our results showed that strains released round shape nanovesicles ranging from 50 to 500 nm. Totally, 112 various proteins were identified in OMVs by proteomic analysis. The isolated OMVs were negative for both CagA and VacA virulence factors. Treatment of HSCs with -derived OMVs significantly increased the expression of fibrosis markers.
In conclusion, the present study demonstrated that -derived OMVs could promote HSC activation and induce the expression of hepatic fibrosis markers. Further research is required to elucidate the definite role of -derived OMVs in liver fibrosis and liver-associated disorders.
是一种普遍存在的致病性细菌，存在于人类的胃部。外膜囊泡（OMVs）是由 释放的纳米级载体，被认为在疾病进展、发病机制和免疫系统调节中起关键作用。有大量证据表明 在胃肠道外疾病中特别是肝脏相关疾病中发挥作用。然而， 导致胃肠道外发病的确切机制仍不清楚。在本研究中，我们旨在确定 分离的 OMVs 对肝星状细胞（HSC）激活和肝纤维化标志物表达的影响。
使用了 5 株具有不同基因型谱的 临床株。使用超速离心法分离 OMVs，并通过扫描电子显微镜（SEM）和动态光散射（DLS）进行分析。应用液相色谱串联质谱（LC-MS/MS）分析确定 衍生的 OMVs 的蛋白成分。MTT 法测定 OMVs 暴露的 LX-2 人肝星状细胞系的细胞活力。用 OMVs 处理 LX-2 细胞 24 小时。用定量实时 PCR 分析 OMVs 处理后 HSC 的 -SMA、E-钙黏蛋白、波形蛋白、snail 和 -连环蛋白基因表达。用免疫细胞化学法评估作为研究较为深入的促纤维化标志物的 -SMA 蛋白表达。
我们的结果表明， 菌株释放出 50 至 500nm 的圆形纳米囊泡。通过蛋白质组学分析，共鉴定出 112 种不同的 OMVs 蛋白。分离的 OMVs 均为阴性，既无 CagA 也无 VacA 毒力因子。用 衍生的 OMVs 处理 HSCs 可显著增加纤维化标志物的表达。
综上所述，本研究表明 衍生的 OMVs 可促进 HSC 激活并诱导肝纤维化标志物的表达。需要进一步研究以阐明 衍生的 OMVs 在肝纤维化和与肝脏相关的疾病中的确切作用。
