Table 1. Application of stem cells for the therapy of erectile dysfunction.
| SCs type | SCs form | Model system | Study duration | Functional results | Histology and molecular results |
|---|---|---|---|---|---|
| Rat BMSCs102 | Cell (gene modified with eNOS) | Aged rats | 3 weeks | Enhanced ICP during CN electrostimulation. Better enhancement when combined with eNOS gene therapy | Enhanced eNOS expression, and cGMP levels. Transplanted cells exhibited ECs and SMCs markers |
| Human BMSC103 | Cell | Young adult rats | 2 weeks | No functional testing. | Transplanted cells exhibited ECs and SMCs markers |
| Rat BMSCs106 | Cell (isolated by p75 NGF receptor) | Young adult rats with CN crush | 4 weeks | Enhanced ICP during CN electrostimulation. Better enhancement for p75-derived BMSCs | p75-derived BMSCs secreted significantly more basic NGF than control group |
| Rat BMSCs107, 109 | Cell (gene modified with VEGF) | Young adult rats with DM I | 4 weeks | Enhanced ICP during CN electrostimulation. Better enhancement when combined with VEGF gene therapy | Increased content of smooth muscle and endothelium in corporal cavernosum. Transplanted cells exhibited ECs and SMCs markers |
| Rat MDSCs115 | Cell | Young adult rats with CN transaction | 2 weeks, 4 weeks | Enhanced ICP during CN electrostimulation | Increased percent area of PGP 9.5 staining |
| Mouse MDSCs78 | Cell | Young adult rats and aged rats | 2 weeks, 4 weeks | Enhanced ICP during CN electrostimulation in aged rats (2 weeks) and young adult rats (4 weeks) | Increased content of smooth muscle in corporal cavernosum. Transplanted cells exhibited SMCs markers |
| Rabbit MDSC114 | ACCMs seeded with MDSCs | Young adult rabbits | 2 months, 4 months, 6 months | No functional testing | Cells expressing ECs and SMCs markers and better arranged growth were prevalent |
| Rat EPCs132 | Cell (gene modified with VEGF) | Young adult rats with DM I | 3 weeks | Enhanced ICP during CN electrostimulation | Enhanced neovascularisation in the corpora cavernosum. Transplanted cells exhibited ECs markers |
| Human UCBSCs 134 | Cell | Senior human with DM II | 11 months | Regained morning erections in some patients. Increased rigidity, but was insufficient for penetration | No relevant testing |
| Rat ADSCs123 | Cell | Young adult rats | 4 weeks | No functional testing | Injected ADSCs were localized to the sinusoid endothelium. Some Transplanted cells exhibited ECs markers |
| Rat ADSCs126 | Cell | Young adult rats with hyperlipid-emia | 4 weeks | Enhanced ICP during CN electrostimulation | Increased content of smooth muscle and endothelium in corporal cavernosum, and nNOS-positive nerve fibres in penile dorsal nerves |
| Rat ADSCs127 | Cell | Adult ZDF rats with DM II | 4 weeks | Enhanced ICP during CN electrostimulation | Increased nNOS staining area in penile dorsal nerves. Inhibition of apoptosis in corpus cavernosum |
| Rat ADSCs129 | Cell and cell lysate | Young adult rats with CN crush | 4 weeks | Enhanced ICP during CN electrostimulation | Increased content of smooth muscle in corporal cavernosum, and nNOS-positive nerve fibres in penile dorsal nerves. Inhibition of fibrosis and apoptosis |
| Human fetal NCSCs137 | Cell | Young adult rats | 2 weeks | No functional testing | Transplanted cells exhibited ECs and SMCs markers |
| Rat fetal BDSCs136 | Cell | Young adult rats | 6 weeks | No functional testing | Transplanted cells exhibited SMCs markers or VEGF |
| Rat GRPCs140 | Cell | Young adult rats with spinal cord injury | 12 weeks | Preserved full and partial erectile events per 24 h | GRPCs survived, differentiated and formed extensive transplants that were well integrated with host tissue |
| Rat neural ESCs141 | Cell | Young adult rats with CN crush | 12 weeks | Enhanced ICP during CN electrostimulation | Increased neurofilament staining in the MPG and penile dorsal nerves. Improved morphological characteristics of nerve fibres in the corpora cavernosum |
Abbreviations: ACCMs, acellular corporal collagen matrices; ADSCs, adipose tissue derived stem cells; BDSCs, brain-derived stem cells; BMSCs, bone marrow mesenchymal stem cells; CN, cavernous nerve; DM I, diabetes mellitus type I; DM II, diabetes mellitus type 2; ECs, endothelial cells; eNOS, endothelial nitric oxide synthase; EPCs, endothelial precursor stem cells; ESCs, embryonic stem cells; GRPCs, glial restricted progenitor cells; ICP, intracavernous pressure; MDSCs, muscle-derived stem cells; MPG, major pelvic ganglia; NCSCs, neural crest stem cells; nNOS, neuronal nitric oxide synthase; SCs, stem cells; SMCs, smooth muscle cells; UCBSCs, umbilical cord blood stem cells. PGP9.5, protein gene product 9.5; NGF, nerve growth factor; VEGF, vascular endothelial growth factor; ZDF, Zucker diabetic fatty.