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Advanced Neurology Cerebrovascular pathology biomarkers in post-COVID-19 patients

in Table 2. It is worth noting that in the comparison
group, the concentration of IL-6 both before and after
treatment was lower in women than in men. Previous
studies have shown that male gender is a risk factor for
more severe disease, with correspondingly higher serum
levels of IL-6 in patients with COVID-19. 17,18 Multiple
genes associated with immune functions are situated
on the X chromosome; therefore, X-linked mosaicism
Figure 3. Vascular endothelial growth factor A (VEGF-A) levels in blood confers a highly polymorphic genetic expression, enabling
serum in patients who had contracted COVID-19 1 – 1.5 years earlier, females to respond with a more expanded immunological
before and after treatment repertoire than men. Nevertheless, in our study, no
19
a
Notes: P < 0.05 when comparing the serum VEGF-A levels of the gender differences in the concentration of IL-6 were found
experimental group and the comparison group before treatment; P < 0.05 in the experimental group.
b
when comparing the serum VEGF-A levels of the experimental group
t
after and before treatment; P < 0.05 when comparing the serum IL-6 levels In women in the experimental group, the concentration
of the experimental group and the comparison group after treatment. of ET-1 in the blood serum was lower than the corresponding
indicator in men, but only before treatment. The obtained
Therefore, SARS-CoV-2 leaves its mark not only in
the form of cytokine load but also in the activation of data does not contradict the conclusions of previous
studies that reported more severe endothelial dysfunction
the endothelial system, facilitating the development of in men with COVID-19. 20,21 Overall, pretreatment serum
endothelial dysfunction. This endothelial dysfunction is levels of IL-6, ET-1, and VEGF-A in both male and female
evidenced by the established two-to-threefold increase COVID-19 survivors were higher than those of male and
in the levels of ET-1 and VEGF-A in the blood serum of female comparison group patients.
patients who had COVID-19.
After treatment, the concentration of IL-6 in the blood
Changes in VEGF levels have been described during
both bacterial and viral infections. Human viruses serum of men in the experimental group decreased,
15
while it did not change in the women. Similar changes
may upregulate the expression of VEGF directly or were recorded in the comparison group. The level of
indirectly through various mechanisms involving HIF-1α, ET-1 after treatment significantly decreased in men of
cyclooxygenase 2, activator protein-1, NF-κB, and IL-6. the comparison group but did not change in women.
16
Importantly, the release of VEGF in response to viral Conversely, in the experimental group, there were no
infection does not occur as an isolated event but is part of a changes in men, whereas this indicator of endothelial
molecular network characterized by concomitant increases dysfunction decreased in women. For the concentration of
of proinflammatory systemic cytokines or chemokines such VEGF-A in the blood serum of both groups, there were no
as IL-6, IL-8, and monocyte chemoattractant protein-1, gender differences after treatment.
or imbalances in leukocyte subsets. Therefore, the
overproduction of VEGF appears as a common feature of 3.3. Severity of COVID-19 infection and vaccination
infections or inflammation and is not specific to COVID-19.
Figure 4 illustrates the indicators of the biomarkers of
The 2-week treatment of patients in both groups had patients in the experimental group, categorized by the
different effects on the biomarkers studied. Specifically, severity (mild, moderate, or severe) of COVID-19 they
IL-6 levels in the experimental group did not decrease after experienced 1 – 1.5 years ago.
treatment and remained significantly higher compared to
the comparison group (Figure 1). However, the treatment Notably, there were no differences in IL-6 concentrations,
was more effective in the comparison group, leading to a whereas ET-1 and VEGF-A differed significantly between the
decrease in the IL-6 level. Notably, the treatment had no severity levels of COVID-19. Significantly, mild COVID-19
effect on the ET-1 levels in the blood serum of either group infection had the most significant impact on the endothelial
(Figure 2). In contrast, the serum concentration of VEGF-A system, as evidenced by increased levels of these biomarkers
in patients of both groups decreased almost twofold due to compared to the values in moderate and severe infections. It
treatment (Figure 3), leading to the normalization of this was observed that during the treatment for CVD in patients
indicator in patients in the experimental group. with a mild COVID-19 infection 1 – 1.5 years earlier, there
was no normalization of endothelial dysfunction.
3.2. Gender characteristics Previous studies have shown that in patients with
Gender characteristics in the serum biomarker levels of a history of COVID-19 of varying severity, there is an
inflammation and endothelial dysfunction are presented increase in the expression of VEGF-R2, which may

Volume 3 Issue 2 (2024) 4 doi: 10.36922/an.2878