ASSESSMENT OF PROTEIN OXIDATIVE MODIFICATION MARKERS IN PREGNANT WOMEN WITH HYPERTENSIVE DISORDERS IN THE THIRD TRIMESTER
Hypertensive disorders of pregnancy (HDP) remain one of the leading causes of maternal and perinatal morbidity and mortality worldwide [ACOG Practice Bulletin, 2020]. The pathogenesis of HDP is multifactorial and includes abnormal placentation, endothelial dysfunction, angiogenic imbalance, immune activation, and excessive production of reactive oxygen species (ROS) [Afrose D et al., 2025; Burton GJ et al., 2019]. Oxidative stress (OS), resulting from an imbalance be- tween ROS generation and the efficiency of antioxidant defense, plays a central role in the development of HDP. OS leads to damage of various biomacromole- cules, including lipids, nucleic acids, and proteins [Lian R et al., 2022; Joo EH et al., 2021]. The accumulation of oxidatively modified proteins (OMB) may lead to enzyme dysfunction, impaired structural and transport protein activity, apoptosis, and activation of inflammatory responses [Cuffe JS et al., 2017]. According to recent systematic reviews, OMB are among the most promising biomarkers of OS in obstetric practice and may be considered diagnostic and prognostic indicators of PE [Ibrahim A et al., 2024].
Objective: to determine the levels of oxidatively modified proteins in pregnant women with hypertensive disorders.
MATERIALS AND METHODS.
This study included 65 women in the third trimester of pregnancy, 35 preg- nant women with HDP and 30 women with uncomplicated singleton physiolog- ical pregnancies as controls. OMB levels in serum were determined spectropho- tometrically. Two parameters were analyzed: aldehyde-protein hydrazones (APH) and carbonyl-protein hydrazones (CPH). Measurements were performed before and after in vitro stimulation. Data are presented as median [interquartile range]. OMB levels were expressed in arbitrary units per gram of protein (a.u./g protein). Statistical analysis was carried out using non-parametric methods (Mann-Whit- ney U test, Wilcoxon signed-rank test).
RESULTS.
In the HDP group, a significant increase in OMB levels was observed after stimulation. Median APH rose from 4.28 [3.91–4.81] to 6.86 [6.13–7.44] a.u./g protein (p<0.05), while CPH increased from 3.60 [3.27–4.17] to 4.76 [4.10–5.57] a.u./g protein (p<0.05). In the control group, APH levels also increased after stim- ulation – from 2.93 [2.44–3.15] to 4.14 [3.23–5.28] a.u./g protein (p<0.05). CPH levels increased from 2.98 [2.79–3.14] to 3.26 [2.84–3.39] a.u./g protein, but this change did not reach statistical significance (p>0.05). Between-group comparison demonstrated significantly higher concentrations of both APH and CPH in the HDP group compared to controls, both before and after stimulation (all p<0.05).
CONCLUSIONS.
Pregnant women with hypertensive disorders of pregnancy are characterized by significantly elevated levels of oxidatively modified proteins, reflecting the in- tensity of systemic oxidative stress. The increase in aldehyde-protein hydrazones and carbonyl-protein hydrazones after in vitro stimulation in women with hyper- tensive disorders of pregnancy suggests depletion of adaptive mechanisms and increased susceptibility of protein structures to oxidative damage.
Objective: to determine the levels of oxidatively modified proteins in pregnant women with hypertensive disorders.
MATERIALS AND METHODS.
This study included 65 women in the third trimester of pregnancy, 35 preg- nant women with HDP and 30 women with uncomplicated singleton physiolog- ical pregnancies as controls. OMB levels in serum were determined spectropho- tometrically. Two parameters were analyzed: aldehyde-protein hydrazones (APH) and carbonyl-protein hydrazones (CPH). Measurements were performed before and after in vitro stimulation. Data are presented as median [interquartile range]. OMB levels were expressed in arbitrary units per gram of protein (a.u./g protein). Statistical analysis was carried out using non-parametric methods (Mann-Whit- ney U test, Wilcoxon signed-rank test).
RESULTS.
In the HDP group, a significant increase in OMB levels was observed after stimulation. Median APH rose from 4.28 [3.91–4.81] to 6.86 [6.13–7.44] a.u./g protein (p<0.05), while CPH increased from 3.60 [3.27–4.17] to 4.76 [4.10–5.57] a.u./g protein (p<0.05). In the control group, APH levels also increased after stim- ulation – from 2.93 [2.44–3.15] to 4.14 [3.23–5.28] a.u./g protein (p<0.05). CPH levels increased from 2.98 [2.79–3.14] to 3.26 [2.84–3.39] a.u./g protein, but this change did not reach statistical significance (p>0.05). Between-group comparison demonstrated significantly higher concentrations of both APH and CPH in the HDP group compared to controls, both before and after stimulation (all p<0.05).
CONCLUSIONS.
Pregnant women with hypertensive disorders of pregnancy are characterized by significantly elevated levels of oxidatively modified proteins, reflecting the in- tensity of systemic oxidative stress. The increase in aldehyde-protein hydrazones and carbonyl-protein hydrazones after in vitro stimulation in women with hyper- tensive disorders of pregnancy suggests depletion of adaptive mechanisms and increased susceptibility of protein structures to oxidative damage.
