Up to 80 percent of men experience erectile dysfunction after undergoing surgery to remove a cancerous prostate gland. Now scientists believe a protein can quickly regenerate the nerve that is damaged during such surgery and restore erectile function.
The protein, named sonic hedgehog after a video game character, normally promotes regeneration of nerves and orchestrates the activity of other proteins in the body. In a new study conducted by scientists at Northwestern University Feinberg School of Medicine, the protein was combined with a nanofiber gel, which was applied to crushed cavernous nerves in rats. This is the nerve that is often crushed or pulled during surgery to remove the prostate gland.
Once the nerve is damaged, smooth muscles cells begin to die quickly in the penis. This leads to scarring, which eventually limits blood flow to the penis and results in erectile dysfunction. Speeding up healing of the nerve is critical to prevent nerve cell death and to preserve erectile function.
When principal investigator Carol Podlasek, assistant professor of urology at Feinberg and a member of the Robert H. Lurie Comprehensive Cancer Center of Northwestern University, examined the treated nerves six weeks later, they had regenerated twice as fast as they are able to do on their own. Podlasek believes this discovery could be applied not only to erectile dysfunction in men who have undergone prostate surgery but also when the cavernous nerve is damaged by diabetes.
Podlasek noted that there is a tremendous need for a therapy to treat erectile dysfunction caused by cavernous nerve damage. Loss of the ability to obtain and maintain an erection is a quality of life issue, and a recent survey showed that men undergoing prostate cancer treatment were most concerned about quality of life after surgery.
Concerns about being able to have an erection after surgery is of greater concern, noted Podlasek, because men are being diagnosed with prostate cancer at a younger age and they live longer because of improved treatments.
Results of this latest study are promising and build on previous research in which Podlasek observed a 63 percent decrease in smooth muscle cell death in the penis when sonic hedgehog was administered to damaged cavernous nerves. Further research is needed before the leap is made from rats to men in using the protein to treat erectile dysfunction in men who have had their prostate removed because of cancer.
Bond CW et al. Peptide amphiphile nanofiber delivery of sonic hedgehog protein to reduce smooth muscle apoptosis in the penis after cavernous nerve resection. Journal of Sexual Medicine 201 Jan; 8(1): 78-89