Unraveling the role of oxidative stress and lipid status parameters in the onset of preeclampsia

Maternal hypercholesterolemia would increase the incidence of embryo aneuploidy in couples with recurrent implantation failure

BACKGROUND

The association of dyslipidemia with embryo development and pregnancy outcomes is largely unknown, especially in unexplained recurrent implantation failure (uRIF) patients. Here, this study aimed to explore the impact of abnormal blood lipid levels on embryo genetic status and pregnancy outcomes after preimplantation genetic testing for aneuploidy (PGT-A) from a clinical perspective.

METHODS

This study retrospectively analyzed 502 patients diagnosed as uRIF. They were divided into four groups according to the levels of cholesterol and triglyceride: nonhyperlipidemia group (NonH group), simple hypercholesterolemia group (SHC group), simple hypertriglyceridemia group (SHC group) and mixed hyperlipidemia group (MixH group). At the same time, patients were divided into non-low HDL-C group and low HDL-C group according to their HDL-C level. The outcomes of embryos genetic testing and pregnancy outcomes after PGT-A was analyzed between groups. Binary logistic regression and/or generalized estimating equation (GEE) model were conducted to investigate the association of different types of dyslipidemia with embryonic aneuploidy rate and cumulative live-birth rate.

RESULTS

474 women who met the inclusion criteria were divided into four groups: NonH group (N = 349), SHC group (N = 55), SHT group (N = 52) and MixH group (N = 18). Compared with the NonH group, SHC group had a significantly increased rate of embryo aneuploidy [48.3% vs. 36.7%, P = 0.006; adjusted OR (95% confidence interval) = 1.52(1.04-2.22), P = 0.029], as well as a reduced number of good-quality embryos on day 5 or 6 [3.00 ± 2.29 vs. 3.74 ± 2.77, P = 0.033]. The SHC group showed a tendency of a lower cumulative live birth rate (47.0% vs. 40.0%), a lower incidence of good birth outcome (37.2% vs. 34.5%) and a higher risk of clinical pregnancy loss (11.1% vs. 17.9%), but did not reach statistical significance (P > 0.05). The incidences of obstetric or neonatal complications and other adverse events were similar in the four groups. Whether patients have low HDL-C did not differ in pregnancy outcomes.

CONCLUSIONS

We found that uRIF women with hypercholesterolemia had an increased proportion of aneuploid embryos and a reduced proportion of high-quality embryos, while different types of hyperlipidemia had no correlation with cumulative live birth rate as well as pregnancy and neonatal outcomes.

Biochemical and hematological parameters in the 1st trimester of pregnancy

The 1st trimester of pregnancy is accompanied with changes in different biochemical and hematological parameters. Analyses scheduled to be performed in the 1st trimester are complete blood count, blood group, Rh factor and the double test. Many experts also suggest the determination of lipid status parameters as a routine analysis in the early pregnancy. Reliable data about maternal and fetal health can be obtained by the assessment of the above-mentioned parameters. They may be helpful in assessing the risk for pregnancy complication development and/or perinatal adverse outcomes.

Correlation of Blood Lipid and Serum Inflammatory Factor Levels With Hypertensive Disorder Complicating Pregnancy

Purpose

To explore the changes of blood lipid and serum inflammatory factors in pregnant women with hypertensive disorder complicating pregnancy (HDP) and the relationship with disease development.

Methods

107 pregnant women with HDP who had regular prenatal examination in our hospital from July 2018 to July 2021 were selected as the research objects. According to the severity of the disease, they were divided into gestational hypertension group, mild preeclampsia group and severe preeclampsia group. 30 healthy pregnant women who underwent prenatal examination in the same period were selected as the healthy group. Serum total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), lipoprotein-associated phospholipaseA2 (Lp-PLA2), C- reactive protein (CRP), interleukin -6 (IL-6), tumor necrosis factor-α (TNF-α) were measured. Receiver operating characteristic curve (ROC) was used to analyze the predictive value of blood lipid and serum inflammatory factors in pregnant women with HDP.

Results

The levels of serum TC, TG and LDL-C increased with the progression of HDP, the level of serum HDL-C decreased with the progression of HDP (P < 0.05). The levels of serum Lp-PLA2, CRP, IL-6 and TNF-α increased with the progression of HDP (P < 0.05). The AUC of serum TC, TG, HDL-C and LDL-C levels for predicting HDP were 0.759, 0.854, 0.770 and 0.785, respectively. The AUC of serum Lp-PLA2, CRP, IL-6 and TNF-α levels for predicting HDP were 0.873, 0.991, 0.966 and 0.999, respectively.

Conclusion

The levels of blood lipid and serum inflammatory factor are closely related to HDP, which has certain value in predicting the occurrence and development of HDP.

Foetal lipoprotein oxidation and preeclampsia

Preeclampsia (PE) is a multisystemic syndrome specific to pregnancy. Although PE is the leading cause of death from complications associated with pregnancy, its aetiology is still unknown. In PE, lipid metabolism is altered. When lipids are damaged, both the mother and the foetus may be at risk. Lipoproteins contain apolipoproteins, triacylglycerols, free and esterified cholesterol, and phospholipids, all of which are susceptible to oxidative stress when high levels of oxygen and nitrogen free radicals are present. Lipoperoxidation can occur in three stages: mild, moderate, and severe. In severe lipid damage, highly toxic products such as malondialdehyde (MDA) can be generated; under these conditions, low-density lipoprotein (LDL) proteins can be oxidized (oxLDL). oxLDL is a biomolecule that can affect the production of nitric oxide (NO), the main vasodilator derived from the endothelium. oxLDL can interfere with the transduction of the signals responsible for triggering the activation of endothelial nitric oxide synthase (eNOS), causing reduced vasodilation and endothelial dysfunction, which are the main characteristics of preeclampsia. The objective of the review was to analyse the information the current information about exists about the impact generated by the oxidation of LDL and HDL lipoproteins in neonates of women with preeclampsia and how these alterations can predispose the neonate to develop diseases in adulthood.

PE can cause foetal loss, intrauterine growth restriction, or developmental complications. Neonates of mothers with PE have a high risk of cardiovascular diseases, stroke, mental retardation, sensory deficiencies and an increased risk of developing metabolic diseases. PE not only affects the foetus, generating complications during pregnancy but also predisposes them to chronic diseases in adulthood.

Atherosclerosis Development and Progression: The Role of Atherogenic Small, Dense LDL

Atherosclerosis is responsible for large cardiovascular mortality in many countries globally. It has been shown over the last decades that the reduction of atherosclerotic progression is a critical factor for preventing future cardiovascular events. Low-density lipoproteins (LDL) have been successfully targeted, and their reduction is one of the key preventing measures in patients with atherosclerotic disease. LDL particles are pivotal for the formation and progression of atherosclerotic plaques; yet, they are quite heterogeneous, and smaller, denser LDL species are the most atherogenic. These particles have greater arterial entry and retention, higher susceptibility to oxidation, as well as reduced affinity for the LDL receptor. Increased proportion of small, dense LDL particles is an integral part of the atherogenic lipoprotein phenotype, the most common form of dyslipidemia associated with insulin resistance. Recent data suggest that both genetic and epigenetic factors might induce expression of this specific lipid pattern. In addition, a typical finding of increased small, dense LDL particles was confirmed in different categories of patients with elevated cardiovascular risk. Small, dense LDL is an independent risk factor for cardiovascular diseases, which emphasizes the clinical importance of both the quality and the quantity of LDL. An effective management of atherosclerotic disease should take into account the presence of small, dense LDL in order to prevent cardiovascular complications.