Plasma levels of melatonin, certain cytokines and placental growth factor at non-pharmacological correction of pineal function in pregnant women with intrauterine growth restriction
Authors:   Bukovinian State Medical University, Chernivtsi, Ukraine, Berbets A. 
Published: January 2021

The pineal gland produces the important hormone melatonin, the level of which in the blood of pregnant women decreases in case of placental insufficiency. The effect of dysfunction of the pineal gland on the immune system of pregnant women and on the angiogenic activity of the placenta during pregnancy remains insufficiently studied. Objective: to establish the effect of our method of non-drug correction of function of pineal gland on the state of the cytokine part of the immune system and on the synthesis of placental growth factor (PlGF) in pregnant women with placental insufficiency manifesting as fetal intrauterine growth restriction (IUGR). Material and methods. 46 pregnant women with IUGR at 30-36 weeks of gestation were examined. The group was divided into two subgroups: with non-drug correction of the pineal gland function (n = 25) and without correction (n = 21). The method of correction included a set of measures of following of lighting regimen, activity and sleep for 14 days. The control group consisted of 20 women with uncomplicated pregnancy. Levels of melatonin, PlGF, TNF-α, IL-1β, IL-6, IL-4, IL-10 were determined in the venous blood by enzyme-linked immunosorbent assay. Results. It was established that the concentration of melatonin in the blood of pregnant women with IUGR was significantly reduced, as well as the concentration of PlGF (p < 0.01). Significant changes were also found in pregnant women with placental insufficiency, namely, increased concentrations of proinflammatory cytokines, such as TNF-α (p < 0.05), IL-1-β (p < 0.001) and IL-6 (p < 0.05), comparing to healthy pregnant women. Also, in the group of pregnant women with IUGR the levels of anti-inflammatory cytokines IL-4 (p <0.001) and IL-10 (p < 0.001) were elevated in comparison to the control group. After application of the developed complex of non-drug correction of pineal gland function, the concentration of melatonin in the blood of pregnant women in the subgroup of correction increased significantly, comparing to the subgroup without correction (p < 0.001), as well as the level of PlGF (p < 0.05). Also, significantly lower levels of proinflammatory cytokines TNF-α, IL-1-β and IL-6 were observed in pregnant women in the subgroup of correction (p < 0.01). Regarding anti-inflammatory cytokines, under the influence of the developed complex of measures there was a decrease in the level of IL-4 and an increase in the level of IL-10 (p < 0.01). Conclusions. When the measures, aimed at non-drug correction of function of pineal gland, are applied in pregnant women with placental insufficiency, manifested as IUGR, the following changes are observed: increased of plasma levels of melatonin and placental growth factor, decreased of levels of proinflammatory cytokines. We suggest that the pineal gland exerts its effect on the immune system through melatonin, which moderates the activity of pro- and anti-inflammatory cytokines, thereby reducing the influence of inflammation on placental tissue, what results in increasing of concentrations of placental growth factor in the blood of pregnant women.