Shi Xuetao's team developed an artificial white film to repair penile damage and restore normal erectile function

About half of men between the ages of 40 and 70 have been reported to experience some form of erectile dysfunction, while an estimated 5 percent of men have Peyronie's disease, which manifests as fibrous inelastic scarring of the white membrane on the corpus cavernosum, causing pain, penile curvature or deformity, causing mechanical erectile dysfunction
.
This is an area that receives little attention, but the actual needs are enormous
.

Many previous studies have focused on repairing the urethra, and few studies have focused on restoring erectile function
.
Although clinicians can treat damaged leukoma tissue by combining other tissues in the patient's body with the extracellular matrix to make patches, these patches also have disadvantages, sometimes the immune system rejects them or complications develop at the donor site, and because their microstructure is different from the natural white membrane, these patches are difficult to perfectly replace natural white membrane tissue
.

In recent years, Shi's team has been working to address male reproductive health issues by developing biomaterials, including erectile dysfunction, infertility and Peyronie's disease
.

A fibrous tissue membrane
wrapped around the surface of the corpus cavernosum of the penis.
It is composed of dense collagen fibers and elastic fibers, tightly surrounding the surface of the corpus cavernosum of the penis, which is rich in stretchability

On January 4, 2022, Shi Xuetao's team of South China University of Technology published a research paper
entitled: Bionic artificial penile Tunica albuginea in the journal Matter.

The study developed a synthetic tissue as an artificial white membrane (ATA) that repairs penile damage and restores normal erectile function
on pig models.
The results of this study suggest that ATA can mimic the tissue fiber sheath necessary for maintaining an erection and is expected to be used to repair penile damage
in humans.

Professor Shi Xuetao, the corresponding author of the paper, said that although the problems and results in the process of ATA construction were largely foreseen, they were still surprised by the results of animal experiments, and the pigs immediately resumed normal erectile function
after using ATA.
The biggest advantage of ATA is that similar tissue functions
are achieved by mimicking the microstructure of natural tissues.
And this design method is not limited to modeling white membrane tissue, but can be extended to many other load-bearing tissues
.

To solve this problem, the research team developed an artificial white film (ATA) based on polyvinyl alcohol, which has a curly fiber structure
similar to natural white film tissue.
Therefore, the synthetic material is able to simulate the biomechanical properties
of white films.
Research Alternative conducted laboratory experiments to verify the toxicity and hemocompatibility of this synthetic tissue, since it is designed to stay in the body for a long period of time, and it needs to be determined that it is not harmful
to human tissue.

Next, the research team tested ATA
on small pigs with white membrane damage in Bama.
They found that patches made of synthetic tissue restored erectile function, similar to normal penile tissue, suggesting that the patch successfully replaced the function of
natural tissue.
The researchers analyzed the effects of the ATA patch a month later and found that although artificial tissue could not restore the microstructure of surrounding natural tissue, after the penis was injected with saline, it underwent fibrosis comparable to normal tissue and achieved normal erections
.
Examination results one month after surgery showed that the ATA-treated group achieved very good repairs, although not perfectly
.

Shi Xuetao points out that in penile injury, the white membrane is usually not the only tissue damaged, and the surrounding nerves and cavernous bodies are often damaged, making repair more difficult
.
The focus of the current phase is on repairing damaged individual tissues, and the next stage will be to consider the whole defect or directly reconstruct the artificial penis
.
In addition, the team plans to use this technique to repair other tissue damage, such as the heart and bladder
.

It is worth mentioning that as early as June 2020, Professor Shi Xuetao, Professor Mao Chuanbin of the University of Oklahoma, Professor An Geng of the Third Affiliated Hospital of Guangzhou Medical University published papers in Nature Communications journals, and for the first time in the world, stem cells and 3D printing technology were successfully repaired cavernous body defects
.

In this study, a 3D printed hydrogel scaffold with a surface loaded with heparin-coated was constructed and myogenic stem cells (MDSCs) mutated by hypoxia-inducible factor (HIF-1α) were implanted to prepare bioengineered vascularized cavernous scaffolds
.
The rabbit cavernous body defect was repaired by the tissue engineering stent, and the erection and ejaculation function of the rabbit penis were successfully restored, so that the male rabbit with penile cavernous body injury successfully restored its reproductive ability
.