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Vertebrate reproductive science and technology
REVIEW (Open Access)

Physiological implications of COVID-19 in reproduction: angiotensin-converting enzyme 2 a key player

G. Taru Sharma https://orcid.org/0000-0002-5052-9477 A F , Vikash Chandra A , Pratheesh Mankuzhy https://orcid.org/0000-0002-8284-9969 B , Yasotha Thirupathi A , Dilip Kumar Swain C , Harikrishna Pillai D , Shailesh Kumar Patel E , Mamta Pathak E and SaiKumar Guttula E
+ Author Affiliations
- Author Affiliations

A Department of Physiology, Indian Council of Agricultural Research (ICAR) – Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttarpradesh, India.

B Department of Physiology, Kerala Veterinary and Animal Sciences University, Lakkidi, Pookode, Kerala, India.

C Department of Physiology, UP Pandit Deen Dayal Upadhyaya Pashu Chikitsa Vigyan Vishwavidyalaya Evam Go Anusandhan Sansthan, Mathura, Uttarpradesh, India.

D Animal Husbandry Department, Government of Kerala, Kerala, India.

E Department of Pathology, Indian Council of Agricultural Research (ICAR) – Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttarpradesh, India.

F Corresponding author. Email: gts553@gmail.com

Reproduction, Fertility and Development 33(6) 381-391 https://doi.org/10.1071/RD20274
Submitted: 16 October 2020  Accepted: 19 January 2021   Published: 18 March 2021

Journal Compilation © CSIRO 2021 Open Access CC BY

Abstract

The COVID-19 outbreak, caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), was first identified in China, and it has quickly become a global threat to public health due to its rapid rate of transmission and fatalities. Angiotensin-converting enzyme 2 (ACE2) has been identified as a receptor that mediates the entry of SARS-CoV-2 into human cells, as in the case of severe acute respiratory syndrome coronavirus (SARS-CoV). Several studies have reported that ACE2 expression is higher in Leydig, Sertoli and seminiferous ductal cells of males, as well as in ovarian follicle cells of females, suggesting possible potential pathogenicity of the coronavirus in the reproductive system. Higher ACE2 expression in the human placenta and reports of vertical transmission of SARS-CoV-2 among clinical cases have increased the relevance of further studies in this area. This review focuses on the interaction between SARS-CoV-2 and the ACE2 receptor and speculates on the mechanistic interplay in association with male and female reproductive physiology. In addition, based on the available literature, we discuss the alleged sex differences in terms of the infectivity of SARS-CoV-2, which is claimed greater among males, and further explore the physiological role of ACE2 and 17β-oestradiol for the same.

Graphical Abstract Image

Keywords: COVID-19, SARS-CoV-2, ACE2 receptors, reproductive physiology, gender bias.


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