RESUMEN

BACKGROUND: The epigenetic status of patients 6-month post-COVID-19 infection remains largely unexplored. The existence of long-COVID, or post-acute sequelae of SARS-CoV-2 infection (PASC), suggests potential long-term changes. Long-COVID includes symptoms like fatigue, neurological issues, and organ-related problems, regardless of initial infection severity. The mechanisms behind long-COVID are unclear, but virus-induced epigenetic changes could play a role. METHODS AND RESULTS: Our study explores the lasting epigenetic impacts of SARS-CoV-2 infection. We analyzed genome-wide DNA methylation patterns in an Italian cohort of 96 patients 6 months after COVID-19 exposure, comparing them to 191 healthy controls. We identified 42 CpG sites with significant methylation differences (FDR < 0.05), primarily within CpG islands and gene promoters. Dysregulated genes highlighted potential links to glutamate/glutamine metabolism, which may be relevant to PASC symptoms. Key genes with potential significance to COVID-19 infection and long-term effects include GLUD1, ATP1A3, and ARRB2. Furthermore, Horvath's epigenetic clock showed a slight but significant age acceleration in post-COVID-19 patients. We also observed a substantial increase in stochastic epigenetic mutations (SEMs) in the post-COVID-19 group, implying potential epigenetic drift. SEM analysis identified 790 affected genes, indicating dysregulation in pathways related to insulin resistance, VEGF signaling, apoptosis, hypoxia response, T-cell activation, and endothelin signaling. CONCLUSIONS: Our study provides valuable insights into the epigenetic consequences of COVID-19. Results suggest possible associations with accelerated aging, epigenetic drift, and the disruption of critical biological pathways linked to insulin resistance, immune response, and vascular health. Understanding these epigenetic changes could be crucial for elucidating the complex mechanisms behind long-COVID and developing targeted therapeutic interventions.

Asunto(s)

COVID-19 , Islas de CpG , Metilación de ADN , Epigénesis Genética , SARS-CoV-2 , Humanos , Metilación de ADN/genética , COVID-19/genética , Epigénesis Genética/genética , Masculino , Femenino , Persona de Mediana Edad , Islas de CpG/genética , Adulto , Envejecimiento/genética , Anciano , Estudio de Asociación del Genoma Completo/métodos , Síndrome Post Agudo de COVID-19 , Italia

RESUMEN

Introduction & Backgroundthe SARS-CoV-2 infection determines the COVID-19 syndrome characterized, in the worst cases, by severe respiratory distress, pulmonary and cardiac fibrosis, inflammatory cytokines release, and immunodepression. This condition has led to the death of about 2.15% of the total infected world population so far. Among survivors, the presence of the so-called post-COVID19 syndrome (PPCS) is a common finding. In patients who survived the SARS-CoV-2 infection, overt PPCS presents one or more symptoms such as fatigue, dyspnea, memory loss, sleep disorders, and difficulty concentrating. The pathophysiology of PPCS is currently poorly understood, and whether epigenetic mechanisms are involved in this process is unexplored. Methods & ResultsIn this study, a cohort of 117 COVID19 survivors (post-COVID19) and 144 non-infected volunteers (COVID19-free) were analyzed using pyrosequencing of defined CpG islands previously identified as suitable for biological age determination. Besides, telomere length (TL) and ACE2 and DPP4 receptor expression were determined. The results show a consistent biological age increase in the post-covid population (58,44 {+/-} 14,66 ChronoAge Vs. 67,18 {+/-} 10,86 BioAge, P<0,0001), determining a DeltaAge acceleration of 10,45 {+/-} 7,29 years (+5.25 years above range of normality) compared to 3,68 {+/-} 8,17 years for the COVID19-free population (P<0,0001). A significant telomere shortening parallels this finding in the post-COVID19 cohort compared to COVID19-free subjects (post-COVID19 TL: 3,03 {+/-} 2,39 Kb vs. COVID19-free: 10,67 {+/-} 11,69 Kb; P<0,0001). Additionally, ACE2 expression was decreased in post-COVID19 patients compare to COVID19-free, while DPP-4 did not change. ConclusionIn light of these observations, we hypothesize that some epigenetic alterations are associated with the post-COVID19 condition, particularly in the younger (<60 years). Although the consequences of such modifications on the long-term clinical outcome remain unclear, they might indicate a direction to investigate the pathophysiological basis of the post-COVID19 syndrome.