ABSTRACT Background. Post-COVID syndrome (PCS), characterized by symptoms that persist for more than 4 weeks after initial infection, could increase cardiovascular risk. High-density lipoproteins (HDL) have antiatherogenic functions, such as the ability to promote reverse cholesterol transport (RCT) and antioxidant activity. In this regard, paraoxonase 1 (PON 1) plays a key role. Objective. The aim of this study was to evaluate HDL functions in patients with PCS and compare them with asymptomatic patients (AP) and controls. Methods. The study included 9 patients with PCS, 18 AP and 10 controls. Complete blood count, basic lipoprotein profile, apolipoproteins A-I and B, and inflammatory markers were measured using automated methods. PON 1 activity was evaluated by a spectrophotometric assay, and the 3 steps of RCT, cellular cholesterol (efflux CCE), lecithin-cholesterol acyltransferase (LCAT) activity and cholesteryl ester transfer protein (CETP) activity were evaluated by radiometric assays. Results. There were no differences in sex, age, or general parameters. The AP group had higher PON activity than the control group (94±76 vs. 183±111 vs. 148±58 nmol/mL.min, in controls, AP and PCS, respectively; p=0.049). There were no differences in RCT. Cellular cholesterol efflux (r=-0.45; p=0.049) and CETP (r=- 0.38; p=0.028) had a negative correlation with neutrophil-to-lymphocyte ratio. LCAT had an inverse correlation with ferritin (r=-0.34; p=0.046). Conclusions . Increased antioxidant activity of PON 1 would represent a defensive mechanism against oxidative stress after infection. All the RCT steps had a negative correlation with inflammatory markers. Our findings may explain, at least in part, the link between COVID-19 and atherosclerosis.
RESUMEN Introducción. El síndrome post COVID (SPC), que se caracteriza por síntomas que se extienden superando las 4 semanas post-infección, podría desencadenar aumento en el riesgo cardiovascular. Las lipoproteínas de alta densidad (HDL) presentan funciones antiaterogénicas, como su capacidad para promover el transporte inverso del colesterol (TIC) y su actividad antioxidante, en la que es clave la enzima paraoxonasa 1 (PON 1). Objetivo. Evaluar funcionalidad de HDL en pacientes con SPC comparados con pacientes asintomáticos (PA) y controles. Material y métodos. Se incluyeron 9 individuos con SPC, 18 PA y 10 controles. Se midieron el hemograma, el perfil lipoproteico básico, las apolipoproteínas A-I y B, y marcadores inflamatorios por métodos automatizados. La actividad de PON 1 se evaluó empleando un método espectrofotométrico y los 3 pasos del TIC, eflujo de colesterol (ECC), y actividades de lecitina:colesterol aciltransferasa (LCAT) y proteína transportadora de colesterol esterificado (CETP), por métodos radiométricos. Resultados. No se observaron diferencias en sexo, edad, ni parámetros generales. El grupo PA presentó mayor actividad PON que los controles (94±76 vs. 183±111 vs. 148±58 nmol/mL.min, en controles, PA y SPC, respectivamente; p=0,049). No se observaron diferencias en el TIC. El ECC (r=-0,45; p=0,049) y CETP (r=-0,38; p=0,028) correlacionaron negativamente con el índice neutrófilos/linfocitos. LCAT correlacionó inversamente con la ferritina (r=-0,34; p=0,046). Conclusiones. El incremento de PON 1 en el grupo PA representaría un mecanismo de defensa frente al estrés oxidativo post-infección. Todos los pasos del TIC mostraron una correlación negativa con marcadores inflamatorios. Nuestros resultados podrían explicar, en parte, el vínculo entre COVID y ateroesclerosis.
