ASCL1 negatively correlates with inflammation in pediatric COVID-19, while ACE2 levels vary with disease severity
Background
Dysregulation of the innate immune response to SARS-CoV-2 is a hallmark of severe COVID-19, with neutrophils playing a critical role in driving inflammation and poor outcomes. Understanding the factors that modulate this inflammatory response, particularly in vulnerable populations like children, is crucial. Neuropeptides and related molecules are increasingly recognized for their involvement in neuroimmune crosstalk, influencing inflammatory pathways. This study investigates the expression of specific neuropeptide family members and enzymes like ACE2 and transcription factors like ASCL1 in pediatric COVID-19 to identify potential biomarkers or therapeutic targets that could mitigate disease severity.
Study Design
Researchers collected blood samples from 40 hospitalized children newly diagnosed with COVID-19 and 17 hospitalized children with non-COVID-19 bronchial pneumonia. Baseline clinical data were gathered, and peripheral blood samples were analyzed. Expression levels of neuropeptide-related molecules, specifically ACE (Angiotensin Converting Enzyme), ACE2 (Angiotensin Converting Enzyme 2), and ASCL1 (achaete-scute family bHLH transcription factor 1), were measured using ELISA. Additionally, complete blood counts with differentials, C-Reactive Protein (CRP), liver enzymes, Substance P (SP), Vasoactive Intestinal Polypeptide (VIP), and Gastrin-Releasing Peptide (GRP) were quantified for correlation analysis.
Results
Comparison between 40 COVID-19 patients (43% males) and 17 non-COVID-19 patients (71% males) revealed significant differences in key markers. ACE2 levels in both the non-COVID-19 and moderate COVID-19 groups were significantly higher than in the severe COVID-19 group (p=0.04 and p=0.03, respectively). ASCL1 expression in the non-COVID-19 group was higher than in the overall COVID-19 group (p=0.04), and specifically higher than in the severe COVID-19 group (p=0.02). No significant differences were observed for SP, VIP, or GRP between the COVID-19 and non-COVID-19 cohorts. > ASCL1 demonstrated a strong negative correlation with blood neutrophils (r = -0.534, p<0.001) and CRP (r = -0.522, p<0.001), while showing a positive correlation with lymphocytes (r = 0.572, p<0.001) and aspartate aminotransferase (r = 0.496, p=0.001). No significant correlation was found between ASCL1 and white blood cell count, platelet count, alanine transaminase, or Lactate dehydrogenase.
Key Findings
ACE2levels were higher in non-COVID-19 and moderate COVID-19 groups compared to severe COVID-19 (p=0.04; p=0.03).ASCL1levels were higher in the non-COVID-19 group than in the overall COVID-19 group (p=0.04).ASCL1negatively correlated with blood neutrophils (r = -0.534, p<0.001) andCRP(r = -0.522, p<0.001).ASCL1positively correlated with lymphocytes (r = 0.572, p<0.001).- No significant differences were found for
Substance P,VIP, orGRPbetween groups.
Why It Matters
The observed inverse correlation between ASCL1 and inflammatory markers like neutrophils and CRP suggests that ASCL1 may play a protective or modulatory role in pediatric COVID-19-associated inflammation. Identifying ASCL1 as a potential biomarker could aid in predicting disease severity or guiding therapeutic strategies for children with COVID-19. While this study is observational, it lays groundwork for future research into ASCL1's functional role and whether its modulation could offer a novel approach to managing the exaggerated inflammatory response seen in severe cases. The findings also highlight ACE2 as a severity indicator, reinforcing its known role in SARS-CoV-2 pathogenesis. Further mechanistic studies are needed to explore if ASCL1 could be a target for pharmacological intervention, but it is far from a usable protocol currently.
covid-19
pediatric
inflammation
ascl1
ace2
biomarker