Language
English
Publication Date
4-1-2022
Journal
Journal of Racial and Ethnic Health Disparities
DOI
10.1007/s40615-021-01004-9
PMID
33694125
PMCID
PMC7945617
PubMedCentral® Posted Date
3-10-2021
PubMedCentral® Full Text Version
Post-print
Abstract
BACKGROUND: Covid-19 toll is disproportionate in Blacks although the mechanisms remain incompletely understood. From a biological perspective, several host proteins have received most attention as logical susceptibility targets. Specifically, angiotensin-converting enzyme 2 (ACE2) serves as the epithelial cell receptor and acts in concert with transmembrane protease serine 2 (TMPRSS2). Intriguingly, ACE2 can also suppress the inflammatory response and therefore may impact the severity of Covid-19 infections (from the exuberant immune response a.k.a. "cytokine storm"). We, therefore, assessed expression of ACE2 and TMPRSS2 in Blacks versus Whites.
METHODS: Archived mucosal biopsies from colonoscopic biopsies of visually normal rectal mucosa without concurrent neoplasia or inflammation were used for this study. Total mRNA was isolated and subjected to real-time polymerase chain reaction for ACE2, and TMPRSS2 was assessed from non-Hispanic Blacks (n = 45) and non-Hispanic Whites (n = 38). GAPDH and beta-actin were used for normalization. Multivariable analysis was performed using Analyse-IT software.
RESULTS: ACE2 and TMPRSS2 levels were not altered by gender, BMI, or age. ACE2 levels were lower in Blacks than Whites achieving statistical significance in multivariable (0.51-fold, p = 0.03) but not quite in univariable (p = 0.07) analysis. This downregulation was mirrored in TMRPSS2 in both univariable (p = 0.03) and multivariable analyses (0.41-fold, p = 0.02). Moreover, there was a strong correlation between ACE2 and TMPRSS2 levels (r-squared = 0.78).
CONCLUSIONS: To our knowledge, this is the first report on racial differences inACE2 and TMPRSS2 mucosal expression. This may provide potential biological underpinnings for the disproportionately higher mortality of Covid-19 in Blacks and should spur future studies.
Keywords
Black or African American, Angiotensin-Converting Enzyme 2, COVID-19, Humans, Inflammation, SARS-CoV-2, Covid-19, ACE2, Racial disparities, TMPRSS2
Published Open-Access
yes
Recommended Citation
De La Cruz, Mart; Nunes, David P; Bhardwaj, Vaishali; et al., "Colonic Epithelial Angiotensin-Converting Enzyme 2 (ACE2) Expression in Blacks and Whites: Potential Implications for Pathogenesis Covid-19 Racial Disparities" (2022). Faculty and Staff Publications. 770.
https://digitalcommons.library.tmc.edu/baylor_docs/770
Included in
Biochemical Phenomena, Metabolism, and Nutrition Commons, Biochemistry, Biophysics, and Structural Biology Commons, COVID-19 Commons, Epidemiology Commons, Medical Specialties Commons, Race and Ethnicity Commons, Women's Health Commons