Erectile Dysfunction in Common Neurological Conditions: A Narrative Review - Beyond the Abstract

Neurogenic erectile dysfunction (NED) can be defined as the inability to achieve or maintain an erection due to central or peripheral neurologic disease. Neurologic diseases can also affect the physical ability and psychological status of the patient. All these factors may lead to a primary or secondary NED. Medication history plays an important role since there are many drugs commonly used in neurologic patients that can lead to ED. The first-line treatment for NED is phos-phodiesterase5inhibitors (PDE5i). Second-line treatments include intracavernous and intraurethral vasoactive injections. Third-line treatments are penile prostheses. The efficacy and safety of each treatment modality depend on the specific neurologic condition.1


Gene therapy strategies that can enhance nitric oxide (NO) production or NO-mediated signaling pathways, growth factor-mediated nerve regeneration, or K+ channel activity in the smooth muscle could be promising approaches for the treatment of ED. The recent clinical study using non-viral gene therapy of the Ca2+ activated BK (Max-K) channel for ED patients shows great promise for the future development of gene-based therapy of ED. This modality could help to improve NED induced by diabetes and cavernous nerve injury.2 Although currently available medications have improved ED treatment, many patients still do not benefit from existing pharmacological options, because of their side effects, or due to their limited effectiveness in treating ED related to diabetes mellitus, prostatectomy. Thus, the development of alternative agents and/or approaches for the treatment of ED is needed. Thus, efforts are underway to develop and test new PDE5i (SLx-2101, Avanafil, Udenafil, Mirodenafil, Lodenafil Carbonate) to obtain molecules with improved potency, tolerability, or more convenient dosage schedules.3

Numerous preclinical and clinical studies have demonstrated that stem-cell (SC) therapy was of great potential for patients with NED. Among those studies, intracavernous injection (ICI) was the most frequently adopted route for SC transplantation. Transplantation of ADSCs-based spheroids (ASs) instead of single-cell suspension of free ADSCs (FAs) for NED may be a wiser choice to achieve steady therapeutic outcomes and to reduce risks for future clinical application.4

Written by: Mohamad Moussa, MD, FEBU,1 Mohamad Abou Chakra, MD,2 Baraa Dabboucy, MD, 3 Athanasios G. Papatsoris, MD, MSc, PhD, FEBU, FES,4 Youssef Fares, MD, PhD, EMBA, FACS, FICS, FWAMS5

  1. Chairman of Urology Department, Faculty of Medicine, Lebanese University, Al Zahraa Hospital, Beirut, Lebanon
  2. Department of Urology, Faculty of Medicine, Lebanese University, Beirut, Lebanon
  3. Department of Neurosurgery, Faculty of Medical Sciences, Lebanese University, Beirut, Lebanon
  4. 2nd Department of Urology, School of Medicine, Sismanoglio Hospital, National and Kapodistrian University of Athens, Athens, Greece
  5. Department of Neurosurgery, Neuroscience Research Center, Faculty of Medical Sciences, Lebanese University, Beirut, Lebanon
References:

  1. Moussa, Mohamad, Athanasios G. Papatsoris, Mohamad Abou Chakra, Baraa Dabboucy, and Youssef Fares. "Erectile dysfunction in common neurological conditions: A narrative review." Archivio Italiano di Urologia e Andrologia 92, no. 4 (2020).
  2. Yoshimura, Naoki, Ryuichi Kato, Michael B. Chancellor, Joel B. Nelson, and Joseph C. Glorioso. "Gene therapy as future treatment of erectile dysfunction." Expert opinion on biological therapy 10, no. 9 (2010): 1305-1314.
  3. S Calabro, Rocco, Giovanni Polimeni, and Placido Bramanti. "Recent advances in the treatment of neurogenic erectile dysfunction." Recent patents on CNS drug discovery 9, no. 1 (2014): 41-53.
  4. Xu, Yongde, Yong Yang, Han Zheng, Chao Huang, Xiaoming Zhu, Yichen Zhu, Ruili Guan, Zhongcheng Xin, Zhiqiang Liu, and Ye Tian. "Intracavernous injection of size-specific stem cell spheroids for neurogenic erectile dysfunction: Efficacy and risk versus single cells." EBioMedicine 52 (2020): 102656.
Read the Abstract