Effect of myogenic stem cells on the integrity and histomorphology of repaired transected external anal sphincter

Abstract

In this animal model, administration of myogenic stem cells to transected/repaired anal sphincters did not alter the amount of inflammation nor the volume of striated muscle, suggesting that stem cells might improve contractile function through other cellular processes.

Electrical Stimulation Followed by Mesenchymal Stem Cells Improves Anal Sphincter Anatomy and Function in a Rat Model at a Time Remote From Injury

“…13 at the time of acute injury, the tissues attract growth factors and exhibit subsequent inflammation and fibrosis. 26 however, symptoms often occur much later after anal sphincter trauma. the site of injury, at a time remote from acute trauma, does not demonstrate the environment that occurs at the time of injury.…”

Evaluation of anatomical and functional results of overlapping anal sphincter repair with or without the injection of bone marrow aspirate concentrate: a case–control study

“…Fitzwater et al . proposed that administration of myogenic stem cells improves the contractile function of the EAS through cellular mechanisms other than muscle regeneration.…”

“…White and coworkers [10] found that injection of myogenic stem cells with EAS repair resulted in enhanced contractile function at 3 months compared with repair alone. Fitzwater et al [11] proposed that administration of myogenic stem cells improves the contractile function of the EAS through cellular mechanisms other than muscle regeneration.…”

Functional Outcome of Human Adipose Stem Cell Injections in Rat Anal Sphincter Acute Injury Model

“…Pathi et al, on the other hand, did not find significant advantage in the iv-administration of rat bonemarrow derived MSCs compared with the PBS controls, but the local injections of MSCs were effective according to in vitro assessment [17]. Recently Fitzwater et al noticed that the administration of rat myogenic stem cells enhanced the contractile function of the sphincter without significant changes in histologic morphology, which addresses the paracrine processes in stem cell therapy [14]. To simplify the cell isolation and proliferation process, Mazzanti et al used freshly isolated minimally manipulated bonemarrow derived mononuclear cells without expansion and found them to be as effective as in vitro expanded BM-MSCs in the recovery of iatrogenic anal sphincter rupture [38].…”

“…There are several studies concerning stem cells in the treatment of anal sphincter defects. Rat models with muscle-derived stem cells or myoblasts as the stem cell origin are the most common study designs [10][11][12][13][14], although bigger animals (rabbits, dogs) have been used as well [15,16]. Mesenchymal stem cells (MSC) derived from bone marrow have been used in a few studies and the results are promising [17][18][19].…”