The Role of Adipose Tissue Mesenchymal Stem Cells in Colonic Anastomosis Healing in Inflammatory Bowel Disease: Experimental Study in Rats.

(1) Background: A surgical operation on an inflamed bowel is, diachronically, a challenge for the surgeon, especially for patients with inflammatory bowel disease. Adipose tissue-derived mesenchymal stromal cells are already in use in clinical settings for their anti-inflammatory properties. The rationale of the current study was to use AdMSCs in high-risk anastomoses to monitor if they attenuate inflammation and prevent anastomotic leak. (2) Methods: a total of 4 groups of rats were subjected to a surgical transection of the large intestine and primary anastomosis. In two groups, DSS 5% was administered for 7 days prior to the procedure, to induce acute intestinal inflammation. After the anastomosis, 5 × 10 6 autologous AdMSCs or an acellular solution was injected locally. Macroscopic evaluation, bursting pressure, hydroxyproline, and inflammatory cytokine expression were the parameters measured on the 8th post-operative day. (3) Results: Significantly less intra-abdominal complications, higher bursting pressures, and a decrease in pro-inflammatory markers were found in the groups that received AdMSCs. No difference in VEGF expression was observed on the 8th post-operative day. (4) Conclusions: AdMSCs attenuate inflammation in cases of acutely inflamed anastomosis.