Abstract
Stem cell (SC) therapy for erectile dysfunction (ED) has been investigated in 35 published studies, with one being a small-scale clinical trial. Out of these 35 studies, 19 are concerned with cavernous nerve (CN) injury-associated ED while 10 with diabetes mellitus- (DM-) associated ED. Adipose-derived SCs (ADSCs) were employed in 18 studies while bone marrow SCs (BMSCs) in 9. Transplantation of SCs was done mostly by intracavernous (IC) injection, as seen in 25 studies. Allogeneic and xenogeneic transplantations have increasingly been performed but their immune-incompatibility issues were rarely discussed. More recent studies also tend to use combinatory therapies by modifying or supplementing SCs with angiogenic or neurotrophic genes or proteins. All studies reported better erectile function with SC transplantation, and the majority also reported improved muscle, endothelium, and/or nerve in the erectile tissue. However, differentiation or engraftment of transplanted SCs has rarely been observed; thus, paracrine action is generally believed to be responsible for SC’s therapeutic effects. But still, few studies actually investigated and none proved paracrine action as a therapeutic mechanism. Thus, based exclusively on functional outcome data shown in preclinical studies, two clinical trials are currently recruiting patients for treatment with IC injection of ADSC and BMSC, respectively.
Highlights
Erectile dysfunction (ED) is a term recommended by a panel of experts in 1992 to replace the term “impotence” [1]
While the majority of ED cases can be treated with currently available medications or devices, approximately 20% of the overall ED patient population remains unresponsive to treatment [13], and in certain patient populations, such as those having diabetes mellitus (DM) or having undergone radical prostatectomy (RP), the failure rates are even higher, at 40% [14,15,16]
The reasons are as follows: (1) it is necessary to clarify whether tunica albuginea (TA) injury can truly cause ED, (2) hyperlipidemiaassociated ED has been investigated in only one Stem cell (SC)-for-ED study, (3) aging-associated ED is related to the normal process of aging, not to any specific disease, and (4) these latter two types of ED are usually responsive to PDE5 inhibitors (PDE5Is) treatment
Summary
Erectile dysfunction (ED) is a term recommended by a panel of experts in 1992 to replace the term “impotence” [1]. While the majority of ED cases can be treated with currently available medications or devices, approximately 20% of the overall ED patient population remains unresponsive to treatment [13], and in certain patient populations, such as those having diabetes mellitus (DM) or having undergone radical prostatectomy (RP), the failure rates are even higher, at 40% [14,15,16] Regardless of their therapeutic efficacy or inefficacy, all current treatment options treat only the symptoms, not the underlying causes, and most of them need to be taken by or administered to the patient when having an erection which is perceived as necessary. One of such research efforts is the investigation of stem cells (SCs) as therapeutic agents, and in this review article I will summarize and discuss all available relevant data in this field of research
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
