The Complex Interplay between Serum Testosterone and the Clinical Course of Coronavirus Disease 19 Pandemic: A Systematic Review of Clinical and Preclinical Evidence

Is SARS-CoV-2-induced disease a decisive factor influencing testosterone in males? Findings from a case-control ex post facto study

BACKGROUND

Whether the observed lower total testosterone (tT) levels in male patients with COVID-19 are caused by a direct impact of SARS-CoV-2 infection or are collateral phenomena shared by other systemic inflammatory conditions has not yet been clarified.

OBJECTIVES

To investigate the independent role of COVID-19 in reducing circulating tT levels in men.

MATERIALS AND METHODS

We compared demographic, clinical, and hormonal values of patients with laboratory confirmed COVID-19 admitted during the first wave of the pandemic with a cohort of consecutive male patients admitted to the intensive care unit (ICU) of the same academic center because of severe acute respiratory distress syndrome (ARDS) but without SARS-CoV-2 infection and no previous history of COVID-19. Linear regression model tested the independent impact of COVID-19 on circulating tT levels. Logistic regression model was used to test predictors of death in the entire cohort.

RESULTS

Of 286 patients with COVID-19, 70 men had been admitted to the ICU ( = cases) and were compared to 79 patients equally admitted to ICU because of severe ARDS but negative for SARS-CoV-2 infection and without previous history of COVID-19 ( = controls). Controls were further grouped into noninfective (n = 49) and infective-ARDS (n = 30) patients. At baseline, controls were older (p = 0.01) and had more comorbidities (p < 0.0001). Overall, cases admitted to ICU had significantly lower circulating tT levels compared to controls (0.9 nmol/L vs. 2.1 nmol/L; vs. 1.2 nmol/L; p = 0.03). At linear regression, being negative for COVID-19 was associated with higher tT levels (Coeff: 2.13; 95% confidence interval - CI 0.71-3.56; p = 0.004) after adjusting for age, BMI, comorbidities and IL-6 levels. Only age and IL-6 levels emerged to be associated with higher risk of death regardless of COVID-19 status.

CONCLUSIONS

This case-control ex post facto study showed lower tT levels in men with COVID-19 compared to those without COVID-19 despite both groups have been equally admitted to ICU for severe ARDS, thus suggesting a possible direct impact of SARS-CoV-2 infection toward circulating tT levels and a consequent more severe clinical outcome.

Acute murine-betacoronavirus infection impairs testicular steroidogenesis and the quality of sperm production

Although several testicular alterations promoted by coronavirus infection have been demonstrated, the extent, causes, and players of testicular pathogenesis are not totally understood. The present study aimed to investigate the short-term effects on male fertility of intranasally administered murine hepatitis virus strain 3 (MHV-3), a member of the genus Betacoronavirus, which causes a severe systemic acute infection. This mouse model might be used as a in vivo prototype for investigating the impact of betacoronavirus on the endocrine and exocrine testicular functions with the advantage to be performed in a biosafety level 2 condition. Herein, we performed virological, histopathological, and molecular studies regarding the testicular spermatogenesis and the spermatic quality analyses in an MHV-3-infected C57BL/6 mice. The main outcomes showed that MHV-3 infects mouse testis and induces a testicular inflammatory state, impairing the steroidogenic pathway. The infection led to several alterations in the testicular parenchyma, such as: seminiferous epithelium sloughing, retention of residual bodies, germ cell apoptosis, alterations in intercellular junction proteins, and worse spermatogenic parameters. Moreover, the levels of plasmatic testosterone as well as the quality of sperm production reduced. Therefore, the present data suggest that the viral/inflammatory impairment of the steroidogenic pathway and the consequent imbalance of androgen levels is critical in testicular pathology, disturbing the SC barrier function and the germ cell differentiation. Our study is important for comprehending the effects of beta coronavirus infections on testis function in order to develop treatments that could prevent virus-mediated male infertility.