Altered circadian expression of cytokines in blood of patients with essential hypertension following COVID-19

Abstract

In spite of a vast number of trials devoted to quantitative characteristics of the cytokine profile in patients with various diseases, no exact reference intervals are presented. It is just as important that there is a limited number of trials analyzing circadian rhythms of cytokine synthesis in patients with arterial hypertension. The purpose of the work was to analyze the characteristics of circadian rhythms of cytokines (IL18, IL18 BP, LIF, sLIFr, M-CSF, MCSFR) in patients with Grade II essential arterial hypertension, and to detect pathogenetically significant characteristics developed following Covid-19. Blood samples were taken at 7.00–8.00, 12.00–13.00, 19.00–20.00.00, 00.00–1.00 to determine the levels of IL18, IL18 BP, LIF, sLIFr, M-CSF, MCSFR in 18 patients (56 (95% CI (54–69) years) with essential arterial hypertension (EAH) within three days prior to and following Covid-19. For this, the immunoenzyme method was used. The obtained data demonstrated altered circadian expression of cytokines in the peripheral blood of patients with essential hypertension depending on whether they have EAH or not, and their additional distortion following Covid-19, which is stable in the majority of cases. It is preserved for six months as low IL18 BP (р < 0.001), and twofold increase of sLIFr and MCSF (р < 0,001) at 18.00. A significant association is determined between the circadian rhythms of sLIFr and altered systolic BP resulting in the abnormal rhythm with BP rise at night (night peaker) in patients with EAH following COVID-19. The obtained fundamental data offer prospects for new research of immunopathogenesis following COVID-19 in patients with hypertension taking into account circadian rhythms of cytokines in the blood.