Investigating the relationship between COVID-19 vaccination and ACE2 gene expression in cardiovascular disease

Background: Cardiovascular disease (CVD) is a major global health problem, and the angiotensin-converting enzyme 2 (ACE 2) gene plays a crucial role in SARS-CoV-2  cell entry and cardiovascular homeostasis. Although COVID-19 vaccines are widely used, their potential effects on ACE2 gene expression in individuals with pre-existing cardiac disease remain incompletely understood.

Objective: The aim of this study was to investigate whether ACE2 gene expression is altered by COVID-19 vaccination in cardiac patients compared with healthy controls.

Methods: A total of 90 participants were studied, including 47 healthy controls and 43 patients with confirmed heart disease. Veneous tissue samples were obtained, total RNA extracted and reverse-transcribed to cDNA and ACE2 expression levels were determined by quantitative real-time PCR (qPCR) with  ACTB as the reference gene. Fold-change calculations and correlation tests were performed for statistical analysis.

Results: ACE2 mRNA expression was detectable in venous tissue samples from both patient and control groups. No statistically significant difference in normalized ACE2 expression was observed between healthy controls and  patients with cardiovascular disease (p > 0.05). Correlation analyses showed no significant association between ACTB and ACE2 expression in either group. Although considerable inter-individual variability in ACE2 expression was observed, fold-change analysis did not reveal a consistent directional difference between groups.

Conclusion: These findings indicate that COVID-19 vaccination is not associated with significant alterations in ACE2 mRNA expression in venous tissue of healthy individuals or patients with cardiovascular disease. Further large-scale, multicentre and longitudinal studies are  required to clarify tissue-specific regulation of ACE2 and its potential clinical implications following vaccination.