Functional Outcome After Anal Sphincter Injury and Treatment With Mesenchymal Stem Cells. (5th May 2014)

• Record Type: Journal Article
• Authors: Salcedo, Levilester; Penn, Marc; Damaser, Margot; Balog, Brian; Zutshi, Massarat
• Is Part Of: Stem cells translational medicine. Volume 3:Number 6(2014)
• Page Start: 760
• Page End: 767
• Publication Date: 2014-05-05
• Subjects: Mesenchymal stem cells -- Anal sphincter -- Anal pressures -- i.v. infusion -- Fecal incontinence; Stem cells -- Periodicals; Regenerative medicine -- Periodicals; Periodicals; 616.0277405
• DOI: 10.5966/sctm.2013-0157
• Languages: English
• ISSNs: 2157-6564

Abstract

Abstract : An animal model of mesenchymal stem cell (MSC) treatment in anal sphincter injury was studied. Results show that a single i.m. treatment with MSCs after injury resulted in increased anal pressures similar to those of serial i.v. injections, and these pressures were sustained 5 weeks after injection. Given that MSCs delivered i.m. or i.v. resulted in functional recovery, the i.m. route may be preferable as fewer cells seem to be needed. Abstract: : This research demonstrates the regenerative effects of mesenchymal stem cells (MSCs) on the injured anal sphincter by comparing anal sphincter pressures following intramuscular and serial intravascular MSC infusion in a rat model of anal sphincter injury. Fifty rats were divided into injury ( n = 35) and no injury (NI; n = 15) groups. Each group was further divided into i.m., serial i.v., or no-treatment ( n = 5) groups and followed for 5 weeks. The injury consisted of an excision of 25% of the anal sphincter complex. Twenty-four hours after injury, 5 × 10 5 green fluorescent protein-labeled MSCs in 0.2 ml of phosphate-buffered saline (PBS) or PBS alone (sham) were injected into the anal sphincter for i.m. treatment; i.v. and sham i.v. treatments were delivered daily for 6 consecutive days via the tail vein. Anal pressures were recorded before injury and 10 days and 5 weeks after treatment. Ten days after i.m. MSC treatment, resting and peak pressures were significantly increased compared with those in sham i.m. treatment ( p < .001). When compared with the NI group, the injury groups had anal pressures that were not significantly different 5 weeks after i.m./i.v. treatment. Both resting and peak pressures were also significantly increased after i.m./i.v. MSC treatment compared with treatment with PBS ( p < .001), suggesting recovery. Statistical analysis was done using paired t test with Bonferroni correction. Marked decrease in fibrosis and scar tissue was seen in both MSC-treated groups. Both i.m. and i.v. MSC treatment after injury caused an increase in anal pressures sustained at 5 weeks, although fewer cells were injected i.m. The MSC-treated groups showed less scarring than the PBS-treated groups, with the i.v. infusion group showing the least scarring.