Mesenchymal Stem Cells Enhance Colonic Anastomotic Repair Through Augmented Collagen Deposition and Decreased Inflammation in a Rat Model.

Background/Objectives: Mesenchymal stem cells (MSCs), due to their regenerative and multipotent properties, have emerged as promising therapeutic agents in tissue repair and regeneration. These biological characteristics might contribute to optimized anastomotic healing and to a reduction in postoperative complications following digestive surgery. The present study aimed to evaluate whether intraperitoneal or perianastomotic administration of MSCs provides superior healing outcomes in colonic anastomoses in Wistar rats. Methods: MSCs were isolated from inguinal adipose tissue harvested from 2 Wistar rats. Thirty male Wistar rats were allocated to 3 groups: (i) the control group, with regular anastomosis, (ii) peri-anastomotic injection of MSCs, and (iii) intraperitoneal injection of MSCs. The animals were sacrificed on postoperative day 14. The evaluated outcomes included clinical evolution, adhesion index, histological characteristics, and tissue hydroxyproline content. Results: The incidence of anastomotic leakage and the mortality rate were 0%. Therefore, the present study primarily demonstrates changes in surrogate markers of healing, including inflammatory response, collagen deposition, adhesion formation, and hydroxyproline content. The adhesion index was similar in the groups receiving MSC administration (p = 0.05); however, intraperitoneal administration demonstrated superior outcomes when compared to standard anastomosis in reducing adhesion formation (p = 0.002). Histopathological analysis showed a decreased inflammatory process and an increased collagen deposition at the anastomotic site following MSC administration (p < 0.05). Moreover, tissue hydroxyproline levels were significantly increased after both perianastomotic (0.831 ± 0.02, p < 0.05) and intraperitoneal (0.54 ± 0.02, p < 0.05) MSC administration compared with the control group (0.251 ± 0.006). Conclusions: These results suggest that MSC administration may improve histological and biochemical markers associated with colonic anastomotic healing in a non-ischemic experimental model. The experimental model used is suitable for further studies aimed at determining the optimal indications, routes of administration, and adjunctive agents that may potentiate the effects of MSCs.