Functional and histologic effects after implanting pluripotent stem cells in a murine model with sphincterotomy. / Efectos funcionales e histológicos posteriores al implante de células madre pluripotentes en un modelo murino con esfinterotomía.

INTRODUCTION AND AIMS: Fecal incontinence is a disabling condition with devastating consequences for the patients. Medical and surgical options are not very satisfactory, reason by which regenerative medicine has been considered in this field. In the present research, we analyzed functional and histologic effects after implanting pluripotent stem cells (PSCs) in a murine model with sphincterotomy. MATERIALS AND METHODS: Female Wistar rats were subjected to sphincterotomy and divided into three groups. Group 1 (control group) was treated with 300µL of balanced saline solution and group 2 (late treatment) and group 3 (early treatment) received 50,000 PSCs resuspended in 300µL of balanced saline solution. All animals were evaluated through high-resolution anorectal manometry 24hours before and after sphincterotomy and every month for three months. Finally, the rats were euthanized and histopathologic sections from the anal canal were obtained. RESULTS: All groups showed a decrease in resting anal pressure and squeeze anal pressure 24hours after sphincterotomy. At the third month, higher anal pressures in the groups treated with PSCs were detected. Regarding the histologic effects, the microscopic architecture was restored and there was a significant decrease in the inflammatory response in the groups treated with PSCs. CONCLUSION: PSCs implantation improves anal tone, as well as histologic structure, presenting better regenerative results when implanted as early treatment.