P036 Analysis of intestinal tissue from newly diagnosed patients with inflammatory bowel disease reveals distinct proteomic profiles
Baldan-Martin, M.(1)*;Lloro, I.(2);Azkargorta, M.(2);Ramírez, C.(1);Soleto Fernández, I.(1);Orejudo, M.(1);García, S.(1);Mercado, J.(1);Gordillo, C.H.(3);Riestra, S.(4);Rivero, M.(5);Gutiérrez, A.(6);Rodríguez-Lago, I.(7);Fernández-Salazar, L.(8);Ceballos, D.(9);Benítez, J.M.(10);Aguas, M.(11);Bastón-Rey, I.(12);Bermejo, F.(13);Casanova, M.J.(1);Lorente, R.(14);Ber, Y.(15);Royo, V.(16);Esteve, M.(17);Elortza, F.(2);Gisbert, J.P.(1);Chaparro, M.(1);
(1)Hospital Universitario de La Princesa- Instituto de Investigación Sanitaria Princesa IIS-Princesa- Universidad Autónoma de Madrid UAM- and Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas CIBERehd, Gastroenterology Unit, Madrid, Spain;(2)Proteomics Platform- CIC bioGUNE- BRTA Basque Research & Technology Alliance- CIBERehd- ProteoRed-ISCIII, Proteomics Platform, Derio, Spain;(3)Anatomía patológica- Hospital Universitario de La Princesa., Anatomía patológica, Madrid, Spain;(4)Hospital Universitario Central de Asturias and Instituto de Investigación Sanitaria del Principado de Asturias ISPA, Gastroenterology Unit, Oviedo, Spain;(5)Hospital Universitario Marqués de Valdecilla and IDIVAL, Gastroenterology Unit, Santander, Spain;(6)Hospital General Universitario de Alicante- ISABIAL and CIBERehd, Gastroenterology Unit, Alicante, Spain;(7)Hospital Galdakao-Usansolo, Gastroenterology Unit, Vizcaya, Spain;(8)Hospital Clínico Universitario de Valladolid, Gastroenterology Unit, Valladolid, Spain;(9)Hospital Universitario de Gran Canaria Dr. Negrín, Gastroenterology Unit, Las Palmas de Gran Canaria, Spain;(10)Hospital Universitario Reina Sofía and IMIBIC, Gastroenterology Unit, Córdoba, Spain;(11)Health Research Institute IISLaFe and Hospital Universitari i Politecnic La Fe, Gastroenterology Unit, Valencia, Spain;(12)Hospital Clínico Universitario de Santiago de Compostela, Gastroenterology Unit, Santiago de Compostela, Spain;(13)Hospital Universitario de Fuenlabrada and IDIPAZ, Gastroenterology Unit, Madrid, Spain;(14)Hospital General Universitario de Ciudad Real, Gastroenterology Unit, Ciudad Real, Spain;(15)Hospital San Jorge, Gastroenterology Unit, Huesca, Spain;(16)Hospital Universitari Son Espases, Gastroenterology Unit, Palma de Mallorca, Spain;(17)Hospital Universitari Mutua Terrasa and Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas CIBERehd, Gastroenterology Unit, Terrasa, Spain;
Background
Inflammatory bowel disease (IBD) is a complex multi-factorial disease characterized by chronic inflammation of the gastrointestinal tract. Despite significant efforts to understand the pathogenetic mechanisms of IBD, the elucidation of its etiopathology and progression is far from fully understood. The direct analysis of the intestinal tissue from the endoscopy which leads to IBD diagnosis (before starting any treatment) would be the ideal sample to elucidate IBD pathogenesis.
Methods
High-throughput mass-spectrometry-based quantitative proteomic analysis was performed using formalin-fixed paraffin-embedded human intestinal samples from newly diagnosed patients to elucidate the potential mechanisms responsible for gut inflammation in Crohn´s disease (CD) and ulcerative colitis (UC). For this purpose, 192 formalin-fixed paraffin-embedded samples from 40 active UC patients, 67 active CD patients and 46 normal biopsies from healthy controls (HC) were analyzed (Figure 1). Proteins with p-value < 0.05 were considered as significantly dysregulated. Moreover, we used Ingenuity Pathway Analysis (IPA) to analyze the pathways and functions in different locations of the gut (ileum or left colon) that could be related to IBD pathogenesis.
Results
A total of 2,903 proteins were identified, of which 1,010 were differentially expressed between left colon from CD patients and HC. 1,242 proteins were differentially expressed between left colon from UC patients and HC, and 952 differential proteins discriminated between left colon from CD and UC patients. In the comparative study of ileum biopsies from Crohn's disease patients and healthy controls, 956 proteins were differentially expressed (Figure 2). IPA revealed multiple canonical pathways, including EIF2 signaling, regulation of eIF4 and serine/threonine kinase P7056K signaling, mitochondrial dysfunction, and oxidative phosphorylation altered in ileum biopsies from CD patients compared to HC (Figure 3). Regarding the proteomic study in left colon samples, the main canonical pathways enrichment in the comparison of UC and CD with HC were the following: neutrophil extracellular trap signaling pathways, fatty acid oxidation, sirtuin signaling pathway, tRNA charging, and mitochondrial dysfunction (Figure 4).
Conclusion
The proteomic results revealed dysregulated proteins and pathways in ileum and left colon biopsies from patients with active CD and UC compared to HC that may unravel key mechanisms contributing to the pathogenesis of these diseases. The results of the study serve as a starting point for hypotheses to understand the pathogenesis and search for therapeutic targets.