A new study on rhesus macaque confirms the male genital tract as a target of SARS-CoV-2. Published as bioRxiv preprint, this study supports the evidence of male reproductive organs being affected during especially severe coronavirus disease (COVID-19), with resultant erectile dysfunction (ED). Long-term consequences are still largely unknown; however, stem cell treatments offer a viable solution for men dealing with ED.
COVID-19 and erectile disfunction
COVID-19 impacts men more than women. Androgens (male hormones) are deemed responsible for more severe pathology; in fact, their receptors are implicated in viral infection. Also, the excessive production of inflammatory molecules (the so-called cytokine storm) and microvascular thrombo-embolic events are believed to be responsible for multi-organ dysfunction.
Among the affected system is the male genital tract, with ED as a possible consequence of SARS-CoV-2 infection. Economic and psychological pressure, together with the health problems driven by the disease, negatively influence sexual life in several ways. However, COVID-19’s consequences on man’s reproductive health are not only indirect. In fact, ED can be the direct effect of SARS-CoV-2-dependent dysfunction of the epithelium lining blood vessels (the endothelium).
Such endothelial dysfunction plays a pivotal role in COVID-19 symptoms. In the case of ED, SARS-CoV-2 was supposed to corrupt the physiological pathways that regulate erection. In particular, the immune response stimulated by this coronavirus – specifically, the cytokine storm – can cause vascular damage. Given the active and dynamic role played by endothelial cells in the regulation of the tone of vascular smooth muscle of the corpus cavernosum (the spongy tissue that contains the blood vessels that, filled with blood, help make an erection) this endothelial damage can affect erection. What is more, the inflammatory molecules produced during the cytokine storm (e.g. TNF-α, IL-6 and IL-1β) are associated with sexual dysfunction’s clinical progression, and ED is associated with both cardiovascular and immuno-inflammatory diseases (e.g. hypertension and inflammatory bowel disease). Finally, COVID-19 correlates with suppression of the enzyme responsible for the production of nitric oxide (NO), which mediates corpus cavernosum dilation during erection.
The new evidence
Viral RNA was already detected in penile vascular endothelial cells of COVID-19 patients. In the new study, a team of researchers led by experts from the Northwestern University of Chicago (USA) confirmed the presence of the protein used by SARS-CoV-2 to infect cells (Spike) in the male genital tract. The authors utilized a probe based on an anti-SARS-CoV-2 Spike antibody to study COVID-19 pathogenesis in rhesus macaque. Infection was detected in both the testicular and penile tissues, highlighting the possible pathologic outcomes of viral replication in the male genital tract.
«Our results suggest that SARS-CoV-2 rapidly and efficiently infects multiple tissues of the male genital tract early during infection in rhesus macaques. The complex vasculature (…) of the MGT [male genital tract, ndr] make it a potential target of the virus», the authors explain. «Although these studies were done with a rhesus macaque model, it is reasonable to suggest that these observations may also apply to humans infected with SARS-CoV-2 because of several clinical observations relating to male sexual health and fertility. (…) SARS-CoV-2 infection of the penis is potentially associated with the vasculature of the corpus cavernosum, which expresses high levels of ACE2 [the Spike receptor, ndr] in the rhesus macaque and human penile tissue. Because the corpus cavernosum plays a key role in erectile function, the inflammation caused by SARS-CoV-2 infection of the penile vasculature is hypothesized to lead to erectile dysfunction. (…) In addition, treatments for ED such as Viagra and Cialis are known to affect the renin-angiotensin-aldosterone-system where ACE2 functions as a part of the physiologic regulation of blood flow associated with normal erectile function.»
How to treat erectile dysfunction
Besides conventional solutions (such as Viagra and Cialis-based treatments), Adipose-Derived Stem Cells (ADSCs) represent a natural choice to treat erectile dysfunction. They present with several advantages:
- ADSCs can be easily isolated from excess fat and expanded in the laboratory to obtain sufficient numbers for treatment.
- ADSC treatment is tolerable, safe, and efficient.
- ADSC therapy can be combined with other approaches to promote the growth of new blood vessels and reduce cell destruction.
The treatment consists in the injection of ADSCs into the corpus cavernosum. Once injected, stem cells also exert immunomodulating effects, decreasing inflammation and promoting healing. Their mechanism of action is believed to involve the production of several molecules that promote tissue repair, collagen secretion, and reduction of inflammation and apoptosis (cell death), together with the production of new blood vessels.
For more information, please discover ANDROSKILL, Bioscience Institute’s solution for erectile dysfunction. Feel free to contact us at firstname.lastname@example.org or to call us at +971 (0)4 375 722. Our biologist will answer your questions without commitment on your part.
- Kaynar M et al. Tip of the iceberg: erectile dysfunction and COVID-19. Int J Impot Res. 2022 Feb 12;1-6. doi: 10.1038/s41443-022-00540-0
- Madden PJ et al. An immunoPET probe to SARS-CoV-2 reveals early infection of the male genital tract in rhesus macaques. bioRxiv. 2022 Feb 28;2022.02.25.481974. doi: 10.1101/2022.02.25.481974. Preprinte