Effects of adipose tissue-derived mesenchymal stem cells and/or sildenafil citrate in experimental colon anastomosis model.

Abstract

This study aimed to evaluate the healing effects of adipose tissue-derived mesenchymal stem cells (AT-MSC) and sildenafil citrate alone or in combination of colon anastomosis experimental model. A total of 40 female Wistar rats were randomly distributed to four groups: Control (without any intervention post-anas-tomosis), stem cell (AT-MSC injection on the anastomosis site), SIL (oral gavage of 10 mg/kg sildenafil citrate), and stem cell + SIL (AT-MSC injection and oral administration of sildenafil citrate) groups. Rats were euthanized 5 days post-anastomosis. Intra-abdominal adhesion status and anastomotic burst pressure were measured to assess anastomotic healing. Hydroxyproline and TNF-α level, neu-trophil leukocyte infiltration, epithelial regeneration, and necrosis in the anastomosis tissue were examined. Anastomosis leakage and anastomosis burst pressure were not different among the groups. Treatment with sildenafil, stem cell, and stem cell + SIL reduced the degree of perianastomotic adhesions compared to control (p<0.05). A significant increase was noted in hydroxyproline in the stem cell and stem cell + SIL groups (p=0.001). AT-MSC injection alone or in combination with sildenafil citrate reduced the TNF-α concentration at the anastomosis site (p=0.001). Histopathological examination revealed that all treatments enhanced the clearance of the necrotic debris, reduced leukocytes infiltration, and accelerated the retraction of anastomo-sed ends except control (p=0.001). Epithelial regeneration was more pronounced in the stem cell group than other groups (p=0.001). Macrophage density was lower in groups treated with the SIL or stem cell groups than the control and stem cell + SIL groups (p=0.001). Sildenafil citrate and/or AT-MSC in the anastomosed rats promoted the anastomosis healing that was more pro-nounced in groups receiving stem cell injections.