Department of Microbiology and Immunology, Meharry Medical College, Nashville, Tennessee, United States of America.
School of Graduate Studies and Research, Meharry Medical College, Nashville, Tennessee, United States of America.
PLoS Negl Trop Dis. 2018 Sep 17;12(9):e0006792. doi: 10.1371/journal.pntd.0006792. eCollection 2018 Sep.
The protozoan parasite Trypanosoma cruzi, the causative agent of Chagas disease, causes severe morbidity and mortality in afflicted individuals. About 30% of T. cruzi-infected individuals present with cardiac, gastrointestinal tract, and/or neurological disorders. Megacolon, one of the major pathologies of Chagas disease, is accompanied by gastrointestinal motility disorders. The molecular mechanism of T. cruzi-mediated megacolon in Chagas disease is currently unknown. To decipher the molecular mechanism of T. cruzi-induced alteration in the colon during the early infection phase, we exposed primary human colonic epithelial cells (HCoEpiC) to invasive T. cruzi trypomastigotes at multiple time points to determine changes in the phosphoprotein networks in the cells following infection using proteome profiler Human phospho-kinase arrays. We found significant changes in the phosphorylation pattern that can mediate cellular deregulations in colonic epithelial cells after infection. We detected a significant increase in the levels of phosphorylated heat shock protein (p-HSP) 27 and transcription factors that regulate various cellular functions, including c-Jun and CREB. Our study confirmed significant upregulation of phospho (p-) Akt S473, p-JNK, which may directly or indirectly modulate CREB and c-Jun phosphorylation, respectively. We also observed increased levels of phosphorylated CREB and c-Jun in the nucleus. Furthermore, we found that p-c-Jun and p-CREB co-localized in the nucleus at 180 minutes post infection, with a maximum Pearson correlation coefficient of 0.76±0.02. Increased p-c-Jun and p-CREB have been linked to inflammatory and profibrotic responses. T. cruzi infection of HCoEpiC induces an increased expression of thrombospondin-1 (TSP-1), which is fibrogenic at elevated levels. We also found that T. cruzi infection modulates the expression of NF-kB and JAK2-STAT1 signaling molecules which can increase pro-inflammatory flux. Bioinformatics analysis of the phosphoprotein networks derived using the phospho-protein data serves as a blueprint for T. cruzi-mediated cellular transformation of primary human colonic cells during the early phase of T. cruzi infection.
原生动物寄生虫克氏锥虫是恰加斯病的病原体，它会导致受感染个体出现严重的发病率和死亡率。大约 30%的克氏锥虫感染个体表现出心脏、胃肠道和/或神经系统疾病。巨结肠是恰加斯病的主要病理学之一，伴随着胃肠道蠕动障碍。克氏锥虫介导的巨结肠在恰加斯病中的分子机制目前尚不清楚。为了解析克氏锥虫感染早期引起的结肠分子改变机制，我们在多个时间点将侵袭性克氏锥虫鞭毛体暴露于原代人结肠上皮细胞（HCoEpiC），以确定感染后细胞内磷酸蛋白网络的变化，采用蛋白质组谱分析人类磷酸激酶阵列。我们发现，在感染后，磷酸化模式发生了显著变化，这些变化可能介导结肠上皮细胞的细胞失调。我们检测到磷酸化热休克蛋白（p-HSP）27 和转录因子的水平显著增加，这些转录因子调节各种细胞功能，包括 c-Jun 和 CREB。我们的研究证实，磷酸化（p-）Akt S473 和磷酸化 JNK 的水平显著上调，这可能分别直接或间接调节 CREB 和 c-Jun 的磷酸化。我们还观察到细胞核中磷酸化 CREB 和 c-Jun 的水平增加。此外，我们发现感染后 180 分钟，p-c-Jun 和 p-CREB 在细胞核中发生共定位，皮尔逊相关系数最大为 0.76±0.02。磷酸化 c-Jun 和磷酸化 CREB 的增加与炎症和促纤维化反应有关。克氏锥虫感染 HCoEpiC 会导致血小板反应蛋白-1（TSP-1）的表达增加，TSP-1 在高水平时具有成纤维作用。我们还发现，克氏锥虫感染调节 NF-kB 和 JAK2-STAT1 信号分子的表达，这可以增加促炎通量。使用磷酸化蛋白数据得出的磷酸蛋白网络的生物信息学分析为克氏锥虫感染早期克氏锥虫介导的原代人结肠细胞的细胞转化提供了蓝图。
