Effect of mesenchymal stem cell penile transplantation on erectile signaling of aged rats

Stem cell-based therapy targeted at the penile tissue has been lately considered in preclinical studies. This work aimed to assess the effect of intracavernous administration of mesenchymal stem cells (MSCs) in aged rats (n = 100). They were subjected to single intracavernous injection (ICI) of 1.0 million MSCs, followed up for 3, 4 weeks, 3 and 4 months (each group 25 rats) and compared with both adult and aged controls (n = 50). In dissected cavernous tissues, cGMP and histopathology were assessed in addition to intracavernous pressure (ICP) measurement in some anaesthetised rats. The results showed that cavernous tissue cGMP was significantly increased in MSCs transplanted rats in all investigated groups compared with the controls. The mean cavernous cGMP levels after 3 and 4 months of MSCs transplantation were significantly increased compared with those after 3 or 4 weeks. Cavernous tissue ICP measurement showed significant increase in MSCs transplanted groups compared with the controls, more in the long-term follow up than in the shorter one. Histopathological examination detected markedly dilated sinusoidal vascular spaces in the long-term follow-up study. It is concluded that stem cell-based therapy is feasible for age-associated erectile dysfunction and could improve erectile signaling.