ABSTRACT
BACKGROUND: The first step in SARS-CoV-2 infection is binding of the virus to angiotensin converting enzyme 2 (ACE2) on the airway epithelium. Asthma affects over 300 million people world-wide, many of whom may encounter SARS-CoV-2. Epidemiologic data suggests that asthmatics who get infected may be at increased risk of more severe disease. Our objective was to assess whether maintenance inhaled corticosteroids (ICS), a major treatment for asthma, is associated with airway ACE2 expression in asthmatics. METHODS: Large airway epithelium (LAE) of asthmatics treated with maintenance ICS (ICS+), asthmatics not treated with ICS (ICS-), and healthy controls (controls) was analyzed for expression of ACE2 and other coronavirus infection-related genes using microarrays. RESULTS: As a group, there was no difference in LAE ACE2 expression in all asthmatics vs controls. In contrast, subgroup analysis demonstrated that LAE ACE2 expression was higher in asthmatics ICS+ compared to ICSâ¾ and ACE2 expression was higher in male ICS+ compared to female ICS+ and ICSâ¾ of either sex. ACE2 expression did not correlate with serum IgE, absolute eosinophil level, or change in FEV1 in response to bronchodilators in either ICS- or ICS+. CONCLUSION: Airway ACE2 expression is increased in asthmatics on long-term treatment with ICS, an observation that should be taken into consideration when assessing the use of inhaled corticosteroids during the pandemic.
Subject(s)
Adrenal Cortex Hormones/administration & dosage , Angiotensin-Converting Enzyme 2/metabolism , Asthma/drug therapy , Receptors, Virus/metabolism , Respiratory Mucosa/drug effects , Administration, Inhalation , Adrenal Cortex Hormones/adverse effects , Adult , Angiotensin-Converting Enzyme 2/genetics , Asthma/diagnosis , Asthma/enzymology , Asthma/genetics , COVID-19/enzymology , COVID-19/virology , Case-Control Studies , Female , Host-Pathogen Interactions , Humans , Male , Middle Aged , Receptors, Virus/genetics , Respiratory Mucosa/enzymology , SARS-CoV-2/pathogenicity , Time Factors , Up-Regulation , Virus Internalization , Young AdultABSTRACT
In the ongoing coronavirus diseases-2019 (COVID-19) crisis that caused immense suffering and deaths, the choice of therapy for the prevention and life-saving conditions must be based on sound scientific evidence. Uncertainty and apprehension are exacerbated in people using angiotensin-converting enzyme (ACE) inhibitors to control their comorbidities such as hypertension and diabetes. These drugs are reported to result in unfavorable outcome as they tend to increase the levels of ACE2 which mediates the entry of SARS-CoV-2. Amiloride, a prototypic inhibitor of epithelial sodium channels (ENaC) can be an ideal candidate for COVID-19 patients, given its ACE reducing and cytosolic pH increasing effects. Moreover, its potassium-sparing and anti-epileptic activities make it a promising alternative or a combinatorial agent.