ABSTRACT
PURPOSE: Although progenitor cells may contribute to intimal hyperplasia (IH) after arterial injury, positive contribution of IH is variable with type of injury or cells. This study was designed to examine whether differentiated muscle derived stem cells (MDSC) attenuate IH in rat. METHODS: MDSCs were retrieved using preplate techniques from rat calf muscle and MDSCs (preplate 6th culture fraction, pp6) were exposed to VEGF (50 ng/ml) for endothelial differentiation prior to injection. Male rats were divided into two groups (cell treated vs. control) and underwent carotid balloon injury with 2-Fr catheter. The virus containing Green fluorescent protein (GFP) gene was transfected into cells for monitoring. Cells (5x10(6)) were indwelled into carotid artery for 30 minutes after injury and then blood flow was restored. Arteries were harvested at various intervals (1, 2 and 4 weeks) after injury. The intima to media thickness ratio (IMTR) was calculated with morphometric analysis. RESULTS: Endothelial surface markers such as VE-CADHERIN were strongly expressed on differentiated MDSCs. At 4 weeks after injury, IH was predominantly observed in control group compared to cell treated group. The intensity of GFP was strongly observed at 1 week and declined at 4 weeks in carotid artery wall at MDSC group. CD31(+) endothelial cells were observed at MDSC group compared to control. The mean IMTR in cell treated groups were significantly lower than control at 2 weeks (P=0.005) and 4 weeks (P< or =0.001). CONCLUSION: Our study demonstrates that MDSCs therapy promotes re-endothelialization and leads to attenuation of IH after balloon injury in rat.
Subject(s)
Animals , Humans , Male , Rats , Antigens, CD , Arteries , Cadherins , Carotid Arteries , Catheters , Endothelial Cells , Hyperplasia , Muscles , Stem Cells , Vascular Endothelial Growth Factor A , VirusesABSTRACT
PURPOSE: In this study, we tested whether injections of muscle-derived stem cells and alginate(Alg)/polycaprolactone(PCL) after denervation of the pudendal nerve could increase the leak point pressure(LPP) and closing pressure(CP) over the long term in a rat model of urinary incontinence. MATERIALS AND METHODS: Muscle derived stem cells(MDSC) were isolated from the gastrocnemius muscle of normal female rats, and these cells were purified for creating a myogenic population by the preplate technique. In the denervated(D) group, the pudendal nerve was transected bilaterally via a dorsal incision in order to denervate the external urethral sphincter. The denervated external urethral sphincter was injected with Alg/PCL(AP group), or MDSC/Alg/PCL(M group) into the proximal urethra after pudendal nerve transection. At 1 and 3 months, the LPP and CP measurements were visually identified by using the vertical tilt/intravesical pressure clamp model of stress urinary incontinence. The rats were then sacrificed and their urethras were harvested for histology. RESULTS: Both the LPP and CP were significantly lower in the denervated group at each time compared with the normal(N group), AP and M groups, and both the LPP and CP in the N, AP and M groups were significantly higher than those in the D group at both 1 and 3 months. The persistence of MDSC over the period of the study was verified by histology. Thus, pudendal nerve denervation led to a progressive decline in the LPP and CP that was evident at 1 month and this persisted to 3 months, and injection of MDSC/Alg/PCL into the denervated rats led to a long term increase in the LPP and CP. CONCLUSIONS: The N, AP and M groups all had significantly higher LPPs than the D group, and MDSC/Alg/PCL injection into the denervated external urethral sphincter in female rats increased the LPP and CP in both the short and long term. We also observed a long term bulking effect of MDSC/Alg/PCL injection in the stress incontinence animal model.
Subject(s)
Animals , Female , Humans , Rats , Denervation , Models, Animal , Muscle, Skeletal , Pudendal Nerve , Stem Cells , Urethra , Urinary IncontinenceABSTRACT
50%) or cultured with low concentration of serum,these cells tended to fuse to form myotubes,and were skeletal myosin~+.CONCLUSION: Preplate technique can effectively isolate MDSCs,this provides tissue engineering with a new type of seed cells.