• ALEETA MARIA JOLLY Department of Pharmacology, Amrita School of Pharmacy, Amrita Vishwa Vidyapeetham, Ponekkara, Kerala, India.
  • JAYA THOMAS Department of Pharmacology, Amrita School of Pharmacy, Amrita Vishwa Vidyapeetham, Ponekkara, Kerala, India.



COVID-19, Angiotensin-converting enzyme 2, Transmembrane serine protease 2, Obesity, Smoking, Alcohol, Antioxidant, Comorbidity, Climate, Pollution


Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) enters into host cells through the angiotensin-converting enzyme 2 (ACE2) receptor and transmembrane serine protease 2 (TMPRSS2) helps in propagation. Expression of ACE2 gene was found to be higher in kidney, testis, heart, thyroid, and adipose tissue whereas expression of TMPRSS2 was found to be highest in the kidney, small intestine, and prostate. ACE2 and TMPRSS2 expression increases as age increases. Estrogen has a protective role against SARS-CoV-2. Thus mortality rate of SARS-CoV-2 is more in men compared to women. ACE2 is also expressed in adipose tissue therefore as body mass index increases the disease severity increases. Smoking upregulates the lung airway expression of ACE2 and TMPRSS2. Alcoholics have more chances to get a COVID-19 as it elevates the expression of the angiotensin II type 1 receptor. Administer an antioxidant-rich diet to fight against COVID-19. Patients with hypertension, diabetes, cardiovascular disease, chronic lung disease, chronic kidney disease, and cancer cause more severity to COVID-19. ACE2 expression increased while administering drugs such as ACE inhibitors, angiotensin II type I receptor blocker, thiazolidinediones, and NSAIDs thus elevates the severity of COVID-19 infection. Anti-histo-blood natural antibodies act as a protective role in blood group O. Blacks and Histapanic community have a higher risk of infection and mortality compared white people. Temperature and humidity are negatively correlated with COVID-19. ACE2 expression is elevated in the alveolar cells of the population exposed to air pollution thus elevates the exposure to the SARS-CoV infection. In this article, we will compare the modifiable and non-modifiable risk factors of COVID-19 that affect both first and second waves.


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How to Cite

JOLLY, A. M., & THOMAS, J. (2022). ANGIOTENSIN-CONVERTING ENZYME 2 AND TMPRSS2 EXPRESSIONS IN COVID-19. Innovare Journal of Medical Sciences, 10(3), 1–5.



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