Abstract Background: Teduglutide is an enterotrophic analogue of glucagon-like peptide-2, with an indirect and poorly understood mechanism of action, approved for the rehabilitation of short-bowel syndrome. This study aims to analyze the response of tissue growth factors to surgical injury and teduglutide administration on an animal model of intestinal anastomosis. Methods: Wistar rats (n = 59) were distributed into four groups: "ileal resection" or "laparotomy", each one subdivided into "postoperative teduglutide administration" or "no treatment"; and sacrificed at the third or the seventh day, with ileal sample harvesting. Gene expression of insulin-like growth factor 1 (Igf1), vascular endothelial growth factor a (Vegfa), transforming growth factor β1 (Tgfβ1), connective tissue growth factor (Ctgf), fibroblast growth factor 2 (Fgf2), fibroblast growth factor 7 (Fgf7), epidermal growth factor (Egf), heparin-binding epidermal-like growth factor (Hbegf), platelet-derived growth factor b (Pdgfb) and glucagon-like peptide 2 receptor (Glp2r) was studied by real-time polymerase chain reaction. Results: Upregulation of Fgf7, Fgf2, Egf, Vegfa and Glp2r at the third day and of Pdgf at the seventh day was verified in the perianastomotic segment. Teduglutide administration was associated with higher fold-change of relative gene expression of Vegfa (3.6 ± 1.3 vs. 1.9 ± 2.0, p = 0.0001), Hbegf (2.2 ± 2.3 vs. 1.1 ± 0.9, p = 0.001), Igf1 (1.6 ± 7.6 vs. 0.9 ± 0.7, p = 0.002) and Ctgf (1.1 ± 2.1 vs. 0.6 ± 2.0, Conclusions: Those results underscore the recognized role of Igf1 and Hbegf as molecular mediators of the effects of teduglutide and suggest that other humoral factors, like Vegf and Ctgf, may also be relevant in the perioperative context. Induction of Vegfa, Igf1 and Ctgf gene expressions might indicate a favorable influence of teduglutide on the intestinal anastomotic healing.

Resumen Introducción: teduglutida es un análogo intestinotrófico do péptido-2 similar al glucagón, con un mecanismo de acción indirecto y poco conocido, aprobado para la rehabilitación del síndrome de intestino corto. Este estudio propone analizar la respuesta de los factores de crecimiento tisulares a la agresión quirúrgica y a la administración de teduglutida en un modelo animal de anastomosis intestinal. Métodos: ratones Wistar (n = 59) fueron distribuidos en cuatro grupos: "resección ileal" o "laparotomía", cada uno subdividido en "administración post-operatoria de teduglutida" o "sin tratamiento"; y sacrificados en el tercero o el séptimo día, con recogida de muestras ileales. La expresión génica de Igf1, Vegfa, Tgfβ1, Ctgf, Fgf2, Fgf7, Egf, Hbegf, Pdgfb y Glp2r fue analizada por qRT-PCR. Resultados: en el segmento perianastomótico se verificó una sobrerregulación de Fgf7, Fgf2, Egf, Vegfa y Glp2r al tercer día y de Pdg al séptimo día. La administración de teduglutida se asoció con mayor cambio de la expresión génica relativa de Vegfa (3.6 ± 1.3 vs. 1.9 ± 2.0, p = 0.0001), Hbegf (2.2 ± 2.3 vs. 1.1 ± 0.9, p = 0.001), Igf1 (1.6 ± 7.6 vs. 0.9 ± 0.7, p = 0.002) y Ctgf (1.1 ± 2.1 vs. 0.6 ± 2.0, p = 0.013); y menor cambio de Tgfβ1, Fgf7 y Glp2r. Conclusiones: estos resultados refuerzan el reconocido papel de Igf1 y Hbegf como mediadores moleculares de los efectos de la teduglutida y sugieren que otros factores humorales, como Vegf y Ctgf, también pueden ser relevantes en el contexto perioperatorio. La inducción de las expresiones de los genes Vegfa, Igf1 y Ctgf podría indicar una influencia favorable de teduglutida en la cicatrización anastomótica intestinal.

Abstract Purpose: To investigate the inflammatory and redox responses to teduglutide on an animal model of laparotomy and intestinal anastomosis. Methods: Wistar rats (n=62) were allocated into four groups: “Ileal Resection and Anastomosis” vs. “Laparotomy”, each one split into “Postoperative Teduglutide Administration” vs. “No Treatment”; and euthanized at the third or the seventh day. Ileal and blood samples were recovered at the baseline and at the euthanasia. Flow cytometry was used to study the inflammatory response (IL-1α, MCP-1, TNF-α, IFN-γ and IL-4 levels), oxidative stress (cytosolic peroxides, mitochondrial reactive species, intracellular glutathione and mitochondrial membrane potential) and cellular viability and death (annexin V/propidium iodide double staining). Results: Postoperative teduglutide treatment was associated with higher cellular viability index and lower early apoptosis ratio at the seventh day; higher cytosolic peroxides level at the third day and mitochondrial overgeneration of reactive species at the seventh day; higher tissue concentration of IL-4 and lower local pro-to-anti-inflammatory cytokines ratio at the seventh day. Conclusion: Those findings suggest an intestinal pro-oxidative and anti-inflammatory influence of teduglutide on the peri-operative context with a potential interference in the intestinal anastomotic healing.