Effects of lipoproteins on endothelial cells and macrophages function and its possible implications on fetal adverse outcomes associated to maternal hypercholesterolemia during pregnancy

Excessive Hypercholesterolemia in Pregnancy Impairs Later-Life Maternal Vascular Function in Rats

BACKGROUND

Preeclampsia is a risk factor for the development of later-life cardiovascular disease. However, the underlying mechanisms are poorly understood. Excessive hypercholesteremia in pregnancy induces a preeclampsia-like phenotype, but whether this also impacts maternal vascular function later in life has not been fully characterized.

METHODS AND RESULTS

Sprague Dawley rats received a control diet (CD) or a high-cholesterol (HCD) diet from gestational day 6 to 20, after which maternal vascular function was assessed 3 months postpartum. Exposure to an HCD in pregnancy reduced later-life endothelium-dependent vasodilation in carotid arteries (-15.24±3.27%), which was mediated via prostaglandin H synthase 2. There were no differences in vasodilation between CD and HCD postpartum rats in the mesenteric arteries, coronary arteries, or aortas. Vasoconstriction to phenylephrine increased in carotid arteries (61.02±21.48%) and reduced in aortas (-23.24±6.19%) of the HCD postpartum group versus CD dams, without differences in mesenteric and coronary arteries. The increased vasoconstriction in carotid arteries was due to lower nitric oxide modulation of constriction. Moreover, carotid artery myogenic response was reduced (-37.68±10.07%) and stiffness was increased (19.67±6.21%) in the HCD postpartum rats compared with CD along with decreased elastin density (-20.85±4.52%). The impact of the HCD on vascular function did not occur in age-matched never-pregnant female rats.

CONCLUSIONS

Excessive hypercholesterolemia in pregnancy impairs later-life maternal vascular function in rats with varying impacts across different vascular beds. Understanding mechanisms for pregnancy-specific excessive hypercholesterolemia provides avenues for targeted intervention strategies to reduce the burden of cardiovascular disease in women who had a complicated pregnancy.

Pathophysiology of Maternal Obesity and Hypertension in Pregnancy

Obesity is one of the biggest health problems in the 21st century and the leading health disorder amongst women of fertile age. Maternal obesity is associated with several adverse maternal and fetal outcomes. In this group of women, the risk for the development of hypertensive disorders of pregnancy (HDPs), such as gestational hypertension (GH) and pre-eclampsia (PE), is increased. In fact, there is a linear association between an increase in pre-pregnancy body mass index (BMI) and PE. Excessive weight gain during pregnancy is also related to the development of PE and GH. The role of obesity in the pathophysiology of HDP is complex and is most likely due to an interaction between several factors that cause a state of poor maternal cardiometabolic health. Adipokines seem to have a central role in HDP development, especially for PE. Hypoadiponectinemia, hyperleptinemia, insulin resistance (IR), and a proinflammatory state are metabolic disturbances related to PE pathogenesis, contributing to its development by inducing a state of maternal endothelial dysfunction. Hypertriglyceridemia is suggested to also be a part of the disease mechanisms of HDP. Therefore, this review seeks to explore the scientific literature to assess the complications of maternal obesity and its association with the development of HDP.

Excessive hypercholesterolaemia during pregnancy as a risk factor for endothelial dysfunction in pre-eclampsia

Pregnancy induces significant changes in the maternal cardiovascular system, and insufficient vascular endothelial adaptations to pregnancy contribute to the development of pregnancy complications such as pre-eclampsia. Pre-eclampsia is not only a major cause of maternal morbidity and mortality, but also a significant risk factor for the development of later-life cardiovascular disease. However, the specific mechanisms underlying the pathophysiology of pre-eclampsia, as well as the mechanisms for an increased susceptibility to cardiovascular disease later in life, are not fully characterized. In this review, we discuss the concept that excessive pregnancy-specific dyslipidaemia, particularly hypercholesterolaemia, is a significant risk factor for the development of pre-eclampsia. We further outline novel potential mechanisms (i.e. oxidized low-density lipoprotein receptor 1 and toll-like receptor 4) underlying endothelial dysfunction induced by excessively high cholesterol levels during pregnancy (in the context of pre-eclampsia), in addition to discussing the overall implications of having had a pregnancy complicated by pre-eclampsia on later-life maternal vascular health. Determining the mechanisms by which excessive, pregnancy-specific dyslipidaemia/hypercholesterolaemia impact maternal endothelial health in pregnancy, and later in life, will create a window of opportunity to diagnose and develop targeted therapy for a susceptible population of women, aiming to ultimately reduce the societal burden of cardiovascular disease.

Body composition in second trimester is associated with dyslipidemia in third trimester

OBJECTIVE

The aim of this study was to examine the correlation between maternal body composition during the second trimester and the occurrence of dyslipidemia in the third trimester.

METHODS

A cohort of 1508 pregnant women who underwent antenatal testing at Shanghai Sixth People's Hospital, affiliated with Shanghai Jiao Tong University School of Medicine, were included in this study. Maternal body composition was assessed using bioimpedance analysis between 14 and 22 weeks of gestation.

RESULTS

Among the 1508 participants, a total of 1420 individuals (94.2%) were diagnosed with dyslipidemia. Notably, there were significant differences in body composition between the normal lipid group and the dyslipidemia group. Logistic regression analysis revealed that various factors including BMI, total body water (TBW), intra-cellular water (ICW), extra-cellular water (ECW), percent body fat (PBF), visceral fat area (VFA), fat-free mass (FFM) and arm circumference (AC) during the second trimester were all found to be associated with dyslipidemia in the third trimester.

CONCLUSION

The present study found that maternal body composition was associated with dyslipidemia. The BMI, TBW, ICW, ECW, PBF, VFA, FFM and AC in second trimester were associated with dyslipidemia in third trimester.

Multi-omics integrative analysis revealed characteristic changes in blood cell immunity and amino acid metabolism in a silkworm model of hyperproteinemia

Hyperproteinemia is a serious metabolic disease of both humans and animals characterized by an abnormally high plasma protein concentration (HPPC). Although hyperproteinemia can cause an imbalance in blood cell homeostasis, the functional changes to blood cells remain unclear. Here, a HPPC silkworm model was used to assess changes to the chromatin accessibility and transcript levels of genes related to blood cell metabolism and immune function. The results showed that HPPC enhanced phagocytosis of blood cells, increased chromatin accessibility and transcript levels of genes involved in cell phagocytosis, proliferation, stress, and programmed death, while genes associated with aromatic amino acid metabolism, and antibacterial peptide synthesis were inhibited in blood cells. Further analysis of the chromatin accessibility of the promoter region found that the high chromatin accessibility of genes sensitive to HPPC, was related to histone modifications, including tri-methylation of lysine residue 4 of histone H3 and acetylation of lysine residue 27 of histone H3. Changes to the chromatin accessibility and transcript levels of genes related to immune function and amino acid metabolism in the blood cells of the HPPC silkworm model provided useful references for future studies of the mechanisms underlying epigenomic regulation mediated by hyperproteinemia.

Maternal Supraphysiological Hypercholesterolemia Is Accompanied by Shifts in the Composition and Anti-Atherogenic Functions of Maternal HDL along with Maternal Cardiovascular Risk Markers at Term of Pregnancy

BACKGROUND

Maternal physiological hypercholesterolemia (MPH) occurs in pregnancy for a proper fetal development. When cholesterol increases over the physiological range, maternal supraphysiological hypercholesterolemia (MSPH) is described, a condition underdiagnosed by a lack of evidence showing its biological and clinical relevance.

AIM

To determine if MSPH associates with maternal vascular dysfunction, along with changes in the composition and function of maternal HDL leading to increased cardiovascular risk.

METHODS

This study included 57 women at term of pregnancy in which a lipid profile was determined.

RESULTS

Maternal total cholesterol (TC) and LDL but not HDL were increased in MSPH women. The isolated HDL from a subgroup of MSPH women had a lower protein abundance and a reduced activity of the antioxidant enzyme PON1; however, an increased antioxidant capacity compared to MPH was observed, along with higher serum levels of α-tocopherol. Moreover, HDL from a subgroup of MSPH women had a lower capacity to induce NO synthesis in endothelial cells compared to MPH. In the circulation, we observed a reduced total antioxidant capacity and augmented levels of soluble VCAM, ApoB, ApoCII, ApoCIII, IL-10, and IL-12p70, as well as the cardiovascular risk ratio ApoB/ApoAI, compared to MPH women.

CONCLUSION

MSPH women present dysfunctional HDL and increased atherogenic cardiovascular risk factors.

Therapeutic potential of traditional Chinese medicine against atherosclerosis: Targeting trimethylamine N-oxide

BACKGROUND

Recent studies have shown that plasma trimethylamine-N-oxide (TMAO) level is highly correlated with the risk of atherosclerosis (AS), and the elevated level is significantly positively correlated with the incidence of AS.

PURPOSE

The purpose of this article is to offer a useful summary of the correlation between TMAO and AS, and the effect of herbal monomers, herbal extracts, and formulas on anti-atherosclerosis mediated by TMAO.

METHOD

The data contained in this article comes from PubMed, Web of Science, and China National Knowledge Infrastructure.

RESULTS

This review discusses the main mechanism of AS induced by TMAO, including endothelial dysfunction, macrophage foaming, platelet reactivity, and cholesterol metabolism, and summarizes 6 herb monomers, 5 herb extracts, and 2 formulas that have been tested for their anti-TMAO activity.

CONCLUSION

The current understanding of possible ways to reduce TMAO generation is discussed, with the effect and potential of herb monomers, herb extracts, and formulas highlighted.

An Overview of Obesity, Cholesterol, and Systemic Inflammation in Preeclampsia

Preeclampsia (PE), an inflammatory state during pregnancy, is a significant cause of maternal and fetal morbidity and mortality. Adverse outcomes associated with PE include hypertension, proteinuria, uterine/placental abnormalities, fetal growth restriction, and pre-term birth. Women with obesity have an increased risk of developing PE likely due to impaired placental development from altered metabolic homeostasis. Inflammatory cytokines from maternal adipose tissue and circulating cholesterol have been linked to systemic inflammation, hypertension, and other adverse outcomes associated with PE. This review will summarize the current knowledge on the role of nutrients, obesity, and cholesterol signaling in PE with an emphasis on findings from preclinical models.