Levels of melatonin and some indicators of angiogenesis, antioxidant system and lipid peroxidation in blood plasma in women with uterine leiomyoma
Authors:   Bukovinian State Medical University, Chernivtsi, Ukraine, Sokolov B. ,   Patna Medical College and Hospital, Patna, India, Berbets A. , Kant Shashi , Yuzko O. 
Published: May 2024

Uterine leiomyoma is one of the most common gynaecological diseases, which often leads to loss of fertility. It is known that in this pathology, damage to the tissues of the uterus is accompanied by oxidative stress, and the mechanisms of its compensation play a decisive role in the process of myometrial regeneration, especially when performing organ-preserving operations. The aim of the study was to determine the levels of melatonin, reproductive hormones and state of angiogenesis, antioxidant system and lipid peroxidation in women of reproductive age who were diagnosed with uterine leiomyoma. Material and methods. 60 women of reproductive age with uterine leiomyoma (study group) were examined. The control group consisted of 20 healthy women of the same age group. Melatonin levels in women's blood were determined once, on an empty stomach, at 8 a.m.; the concentrations of estradiol and progesterone in the follicular phase of the menstrual cycle were also measured. The state of the angiogenesis system was studied by examining the levels of vascular endothelial growth factor (VEGF) and the content of the final metabolites of nitric oxide NO in blood plasma. The activity of the antioxidant system was assessed by blood plasma concentrations of reduced glutathione, glutathione peroxidase, and glutathione transferase. Indicators of lipid peroxidation were investigated by the content of malondialdehyde (MDA) in blood plasma and erythrocytes. Results. It was found that in the patients of the study group with leiomyoma, there was a significantly lower level of melatonin in blood plasma (111.1 ± 18.5 ng/mL) compared to the control group (153.5 ± 8.5 ng/mL), while the concentration of estradiol was almost three times higher (107.4 ± 25.3 pg/mL) compared to the control group (36.2 ± 3.2 pg/mL), and the concentration of progesterone was 1.9 times higher (2.1 ± 0.4 ng/mL compared to 1.1 ± 0.5 ng/mL in the control group). The level of VEGF in blood plasma in women with uterine leiomyoma was also higher (90.4 ± 23.6 pg/mL) compared to the control group (35.1 ± 8.3 pg/mL), as well as the concentration of final metabolites of nitric oxide, which reached 25.3 ± 5.9 pg/mL compared to 9.9 ± 3.9 pg/mL in the control group. The reduced glutathione level in the blood plasma of women with uterine leiomyoma was significantly lower (0.77 ± 0.13 µmol/L) compared to healthy women (1.02 ± 0.14 µmol/L) in the control group, while the concentrations of glutathione-S-transferase and glutathione peroxidase enzymes were higher (161.3 ± 22.3 ng/mL and 235.7 ± 35.9 ng/mL, respectively), whereas in the control group these indicators were 118.9 ± 18.0 ng/mL and 105.3 ± 41.2 ng/mL, respectively. The MDA content in women of the study group was higher, measuring 5.2 ± 0.8 nmol/L in plasma and 10.8 ± 1.1 nmol/L in erythrocytes compared to 2.3 ± 0.8 nmol/L and 5.3 ± 0.8 nmol/L in the control group, respectively. Conclusions. The levels of melatonin and reduced glutathione in the blood plasma of women with uterine leiomyoma were significantly lower, while the concentrations of estradiol, progesterone, glutathione-S-transferase, glutathione peroxidase, VEGF, final metabolites of nitric oxide, as well as the average MDA content in plasma and erythrocytes, were significantly higher compared to healthy women. In the study group, the relationship between the level of progesterone in blood plasma and the content of malondialdehyde in erythrocytes was described using a linear regression equation, which, as we suggest, indicates an activating effect of progesterone on oxidative stress mechanisms in the myometrium. In our opinion, oxidative stress in uterine leiomyoma occurs due to inadequate activity of the antioxidant system, an integral part of which is melatonin, leading to enhanced angiogenesis against the background of estrogen-induced myometrial proliferation.