Adipose-derived stem cells on the healing of ischemic colitis: a therapeutic effect by angiogenesis

There has been no specific treatment for ischemic colitis. We verified the effects of adipose-derived stem cells (ASCs) on ischemia-induced colitis in a rat model. Forty male Sprague-Dawley rats (10 weeks old; weight, 350 +/- 20 g) were divided into two groups: a control group (only fibrinogen and thrombin injected, n = 20) and an ASC group (local implantation of ASCs mixed with thrombin and fibrinogen, n = 20). An ischemic colitis model was established by modifying Nagahata's methods with double-blind randomization. ASCs (1 x 10(6) cells) were implanted intramurally into the ischemic area using a fibrin glue mixture. The severity of adhesion, degree of ileus, the number and size of the ulcers, Wallace macroscopic and microscopic scores, and microvascular density were measured. The degree of ileus was significantly lower, and significantly fewer and smaller ulcerations were found in the ASC group than those in the control group. Wallace macroscopic and microscopic scores were lower in the ASC group than in the control group (1.90 +/- 1.22 versus 3.25 +/- 1.83, p < 0.01 and 1.55 +/- 1.88 versus 2.84 +/- 1.89, p < 0.05, respectively). Microvascular density was higher in the ASC group than in the control (54.45 +/- 19.45 versus 26.54 +/- 13.14, p < 0.01, respectively). Local implantation of ASCs into an ischemic-injured colonic wall reduced the grade of ischemic injury and enhanced tissue healing by promoting angiogenesis.