Laboratory of Medical Microbiology, Hellenic Pasteur Institute, Athens, Greece.
Department of Genetics and Biotechnology, Faculty of Biology, School of Physical Sciences, University of Athens, Athens, Greece.
Helicobacter. 2023 Aug;28(4):e12987. doi: 10.1111/hel.12987. Epub 2023 May 4.
Helicobacter pylori (H. pylori)-induced gastric pathology involves remodeling of extracellular matrix mediated by aberrant activity of matrix metalloproteinases (MMPs). We have previously shown that in vitro H. pylori infection leads to MMP-3 and MMP-9 overexpression, associated with phosphorylation of bacterial oncoprotein CagA. We extended these findings in an in vivo model of H. pylori infection and further assessed the involvement of MAPK pathways in MMP expression.
C57BL/6 mice were infected with H. pylori strains HPARE, HPARE ΔCagA, and SS1, for 6 and 9 months. Transcriptional expression of Mmp-3 and Mmp-9 was evaluated via qPCR while respective protein levels in the gastric mucosa were determined immunohistochemically. Epithelial cell lines AGS and GES-1 were infected with H. pylori strain P12 in the presence of chemical inhibitors of JNK, ERK1/2, and p38 pathways, for 24 h. mRNA and protein expression of MMP-3 and MMP-9 were determined via qPCR and Western blot, respectively.
We observed transcriptional activation of Mmp-3 and Mmp-9 as well as aberrant MMP-3 and MMP-9 protein expression in murine gastric tissue following H. pylori infection. CagA expression was associated with MMP upregulation, particularly during the early time points of infection. We found that inhibition of ERK1/2 resulted in reduced mRNA and protein expression of MMP-3 and MMP-9 during H. pylori infection, in both cell lines. Expressed protein levels of both MMPs were also found reduced in the presence of JNK pathway inhibitors in both cell lines. However, p38 inhibition resulted in a more complex effect, probably attributed to the accumulation of phospho-p38 and increased phospho-ERK1/2 activity due to crosstalk between MAPK pathways.
H. pylori colonization leads to the upregulation of MMP-3 and MMP-9 in vivo, which primarily involves ERK1/2 and JNK pathways. Therefore, their inhibition may potentially offer a protective effect against gastric carcinogenesis and metastasis.
幽门螺杆菌（H. pylori）引起的胃病理学涉及细胞外基质的重塑，这是由基质金属蛋白酶（MMPs）的异常活性介导的。我们之前已经表明，体外 H. pylori 感染会导致 MMP-3 和 MMP-9 的过度表达，与细菌癌蛋白 CagA 的磷酸化有关。我们在 H. pylori 感染的体内模型中扩展了这些发现，并进一步评估了 MAPK 途径在 MMP 表达中的参与。
C57BL/6 小鼠用 H. pylori 菌株 HPARE、HPARE ΔCagA 和 SS1 感染 6 和 9 个月。通过 qPCR 评估 Mmp-3 和 Mmp-9 的转录表达，通过免疫组织化学测定胃黏膜中相应的蛋白水平。AGS 和 GES-1 上皮细胞系在存在 JNK、ERK1/2 和 p38 途径的化学抑制剂的情况下，用 H. pylori 菌株 P12 感染 24 小时。通过 qPCR 和 Western blot 分别测定 MMP-3 和 MMP-9 的 mRNA 和蛋白表达。
我们观察到 H. pylori 感染后，小鼠胃组织中 Mmp-3 和 Mmp-9 的转录激活以及异常的 MMP-3 和 MMP-9 蛋白表达。CagA 的表达与 MMP 的上调有关，特别是在感染的早期时间点。我们发现，在 H. pylori 感染期间，ERK1/2 的抑制导致两种细胞系中 MMP-3 和 MMP-9 的 mRNA 和蛋白表达减少。在两种细胞系中，JNK 途径抑制剂的存在也降低了两种 MMP 的表达蛋白水平。然而，p38 的抑制导致了更复杂的影响，这可能归因于 MAPK 途径之间的串扰导致磷酸化 p38 和增加的磷酸化 ERK1/2 活性的积累。
H. pylori 定植导致体内 MMP-3 和 MMP-9 的上调，主要涉及 ERK1/2 和 JNK 途径。因此，它们的抑制可能对胃癌变和转移提供保护作用。
