Effect of maternal cardiovascular conditions and risk factors on offspring cardiovascular disease

Preventive Cardiology and Risk Assessment: Beyond LDL

PURPOSE OF REVIEW

Risk assessment is the foundational cornerstone for cardiovascular prevention. The goal of this review is to apprise the reader of the latest evidence and guideline-based stepwise method for clinical risk assessment for future atherosclerotic events. We also discuss caveats to the current approach and review future directions including the promise of precision medicine.

RECENT FINDINGS

The most recent cholesterol and prevention guidelines improve upon the widely used pooled cohort equations by incorporating risk-enhancing factors to further personalize risk assessment. For those in whom uncertainty remains, there is mounting evidence for using the coronary calcium score to uncover subclinical disease to either up- or down-classify risk. Although still in its infancy, progress in high-throughput molecular analysis is edging the field closer to more precise risk stratification. Atherosclerosis is the leading cause of global morbidity and mortality. Emphasis on cardiovascular prevention is essential to mitigate the burden of disease. Here, we introduce a "4 + 2" paradigm for approaching preventive cardiology based on recent guidelines. Risk stratification is performed in four steps: qualitative risk approximation to initiate counseling and education, quantitative risk estimation based on a validated model, personalization with risk-enhancing factors, and measurement of coronary artery calcium score in select patients. The two foundational principles of preventive management are to promote a healthy lifestyle in all and to escalate preventive pharmacotherapy based on increasing risk. Shared decision-making remains central throughout this process.

Maternal and gestational influences on childhood blood pressure

Exposures that contribute to a sub-optimal intrauterine environment can have an effect on the developing fetus. Impaired fetal growth that results in low birth weight is an established risk factor for cardio-metabolic disorders later in life. Recent epidemiologic and prospective cohort studies that include the maternal and gestational period have identified maternal and gestational conditions that confer increased risk for subsequent cardio-metabolic disorders in the absence of low birth weight. Maternal pre-conception health status, including chronic obesity and type 2 diabetes, increase risk for childhood obesity and obesity-related higher blood pressure (BP) in child offspring. Maternal gestational exposures, including gestational diabetes, gestational hypertension, and preeclampsia, are associated with higher BP in offspring. Other maternal exposures such as cigarette smoke and air pollution also increase risk for higher BP in child offspring. Recent, but limited, data indicate that assisted reproductive technologies can be associated with hypertension in childhood, despite otherwise normal gestation and healthy newborn. Gestational exposures associated with higher BP in childhood can be related to familial lifestyle factors, genetics, or epigenetic modification of fetal deoxyribonucleic acid (DNA). These factors, or combination of factors, as well as other adverse intrauterine conditions, could induce fetal programing leading to health consequences in later life. Current and developing research will provide additional insights on gestational exposures and fetal adjustments that increase risk for higher BP levels in childhood.

DNA methylation loci in placenta associated with birthweight and expression of genes relevant for early development and adult diseases

Background

Birthweight marks an important milestone of health across the lifespan, including cardiometabolic disease risk in later life. The placenta, a transient organ at the maternal-fetal interface, regulates fetal growth. Identifying genetic loci where DNA methylation in placenta is associated with birthweight can unravel genomic pathways that are dysregulated in aberrant fetal growth and cardiometabolic diseases in later life.

Results

We performed placental epigenome-wide association study (EWAS) of birthweight in an ethnic diverse cohort of pregnant women (n = 301). Methylation at 15 cytosine-(phosphate)-guanine sites (CpGs) was associated with birthweight (false discovery rate (FDR) < 0.05). Methylation at four (26.7%) CpG sites was associated with placental transcript levels of 15 genes (FDR < 0.05), including genes known to be associated with adult lipid traits, inflammation and oxidative stress. Increased methylation at cg06155341 was associated with higher birthweight and lower FOSL1 expression, and lower FOSL1 expression was correlated with higher birthweight. Given the role of the FOSL1 transcription factor in regulating developmental processes at the maternal-fetal interface, epigenetic mechanisms at this locus may regulate fetal development. We demonstrated trans-tissue portability of methylation at four genes (MLLT1, PDE9A, ASAP2, and SLC20A2) implicated in birthweight by a previous study in cord blood. We also found that methylation changes known to be related to maternal underweight, preeclampsia and adult type 2 diabetes were associated with lower birthweight in placenta.

Conclusion

We identified novel placental DNA methylation changes associated with birthweight. Placental epigenetic mechanisms may underlie dysregulated fetal development and early origins of adult cardiometabolic diseases.

Clinical trial registration

ClinicalTrials.gov, NCT00912132

Gestational Exercise and Maternal and Child Health: Effects until Delivery and at Post-Natal Follow-up

We studied the influence of pregnancy exercise on maternal/offspring cardiometabolic health until delivery and at follow-up. We pooled data from two randomized controlled trials from our group that were performed following the same methodology (one unpublished). We also collected follow-up data de novo from the participants of both trials and their offspring. In total, 1348 women with uncomplicated, singleton gestations were assigned to an intervention (n = 688, performing a supervised, moderate-intensity exercise program (three sessions/week)) or control group (n = 660). Maternal outcomes were excessive gestational weight gain (EGWG), gestational hypertension/diabetes and, at follow-up, return to pre-pregnancy weight within six months, hypertension, overweight/obesity, and other cardiometabolic conditions. Offspring outcomes were macrosomia and low-birthweight and, at follow-up, overweight/obesity, low-weight, and cardiometabolic conditions. Adherence to the intervention, which proved safe, was > 95%. Pregnancy exercise reduced the risk of EGWG, gestational hypertension, and diabetes (adjusted odds ratio (OR) and 95% confidence interval: 0.60 (0.46–0.79), 0.39 (0.23–0.67), and 0.48 (0.28–0.84)), and it was associated with a greater likelihood of returning to pre-pregnancy weight (2.37 (1.26–4.54)) and a lower risk of maternal cardiometabolic conditions (0.27 (0.08–0.95)) at the end of follow-up (median 6.1 years (interquartile range 1.8)). Pregnancy exercise also reduced the risk of macrosomia (0.36 (0.20–0.63)) and of childhood overweight/obesity during the first year (0.20 (0.06–0.63)). Our findings suggest that pregnancy exercise might protect maternal/offspring health.

A complicated pregnancy in homozygous familial hypercholesterolaemia treated with lipoprotein apheresis: A case report

BACKGROUND AND AIMS

During pregnancy total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) levels increase significantly and lipoprotein apheresis (LA) is considered the most effective therapy in homozygous familial hypercholesterolaemia (HoFH) for modulating lipid and lipoprotein levels and reducing maternal and foetal complications.

CLINICAL CASE

A primigravida 28 years old Caucasian female patient, previously diagnosed as to be HoFH, was admitted at our outpatient service at the beginning of pregnancy.

METHODS

The patient was continuously submitted to LA every two weeks without foetal complication. During pregnancy two methods have been utilised: selective apheresis, and later plasma exchange. At 33 weeks gestational age the patient developed progressively hypertension, associated to LDL-C levels increase. Weekly LA was favoured.

RESULTS

At 34 weeks +5 days patient suddenly experienced acute chest pain and abnormal electrocardiogram heart tracing and cardiac enzymes increase. An emergency caesarean section was performed without complications and the foetus was healthy. The patient was immediately transferred to Coronary Intensive Care Unit, where she was diagnosed non-ST elevation myocardial infarction (NSTEMI). Notwithstanding the patient improved in few days and was quickly discharged in fair clinical condition.

CONCLUSIONS

LA is a safe and effective tool in HoFH subjects even in pregnancy. Evidence based guidelines for the management of these patients during pregnancy are still lacking.

Childhood Psychosocial Environment and Adult Cardiac Health: A Causal Mediation Approach

INTRODUCTION

This study used causal mediation analysis to assess the life-course associations of a favorable childhood psychosocial environment with left ventricular mass and diastolic function in adulthood and the extent to which adult health behaviors mediate these associations.

METHODS

The sample included 880 participants (56% women) from the Young Finns Study with data on the childhood environment from 1980, adult health behaviors (smoking, physical activity, diet, and BMI) from 2001 and an echocardiographic assessment of the left ventricular mass (g/m^2.7) and diastolic function (E/e' ratio; higher values indicating a lower diastolic function) from 2011. The associations of the childhood environment with the left ventricular mass and E/e' ratio and mediation pathways through health behaviors were assessed using marginal structural models that were controlled for age, sex, and time-dependent confounding by adult socioeconomic position (measured as educational attainment) via inverse probability weighting. The data were analyzed in 2018-2019.

RESULTS

The mean age in 2011 was 41 (range 34-49) years. Those above versus below the median childhood score had a 1.28 g/m^2.7 lower left ventricular mass (95% CI= -2.63, 0.07) and a 0.18 lower E/e' ratio (95% CI= -0.39, 0.03). There was no evidence for indirect effects from childhood environments to left ventricular outcomes through adult health behaviors after controlling for time-dependent confounding by the adult socioeconomic position (indirect effect β= -0.30, 95% CI= -1.22, 0.63 for left ventricular mass; β= -0.04, 95% CI= -0.18, 0.11 for E/e' ratio). The results after multiple imputation were similar.

CONCLUSIONS

A favorable childhood environment is associated with more optimal cardiac structure and function in adulthood. After accounting for socioeconomic positions, adult health behaviors explain little of the associations.

Maternal Diabetes Mellitus as a Risk Factor for High Blood Pressure in Late Childhood

Intrauterine fetal conditions can have lifelong cardiovascular effects. The impact of maternal diabetes mellitus on children's cardiovascular profile is not well established. The goal of this study was to explore the association between maternal diabetes mellitus and offspring's blood pressure (BP) ≤10 years of age. Generation XXI is a prospective birth cohort, which enrolled 8301 mother-offspring pairs, including 586 (7.1%) children of diabetic mothers. The associations between maternal diabetes mellitus and BP at 4, 7, and 10 years of age was modeled using linear regression. A mixed-effects model was built to assess differences in BP variation over time. Path analysis was used to quantify effects of potential mediators. Maternal diabetes mellitus was associated with higher BP in offspring at the age of 10 (systolic: β, 1.48; 95% CI, 0.36-2.59; and diastolic: β, 0.86; 95% CI, 0.05-1.71). This association was independent of maternal perinatal characteristics, and it was mediated by child's body mass index and, to a lesser extent, by gestational age, type of birth, and birth weight (indirect effect proportion, 73%). No significant differences in BP were found at 4 and 7 years of age. Longitudinal analysis showed an accelerated systolic BP increase on maternal diabetes mellitus group (β, 1.16; 95% CI, 0.03-2.28). These finding were especially relevant in males, suggesting sex differences in the mechanisms of BP prenatal programing. Our results provide further evidence that maternal diabetes mellitus is associated with high BP late in childhood, demonstrating a significant role of child's body mass in the pathway of this association.

Cardiovascular effects of prenatal stress-Are there implications for cerebrovascular, cognitive and mental health outcome?

Prenatal stress programs offspring cognitive and mental health outcome. We reviewed whether prenatal stress also programs cardiovascular dysfunction which potentially modulates cerebrovascular, cognitive and mental health disorders. We focused on maternal stress and prenatal glucocorticoid (GC) exposure which have different programming effects. While maternal stress induced cortisol is mostly inactivated by the placenta, synthetic GCs freely cross the placenta and have different receptor-binding characteristics. Maternal stress, particularly anxiety, but not GC exposure, has adverse effects on maternal-fetal circulation throughout pregnancy, probably by co-activation of the maternal sympathetic nervous system, and by raising fetal catecholamines. Both effects may impair neurodevelopment. Experimental data also suggest that severe maternal stress and GC exposure during early and mid-gestation may increase the risk for cardiovascular disorders. Human data are scarce and especially lacking for older age. Programming mechanisms include aberrations in cardiac and kidney development, and functional changes in the renin-angiotensin-aldosterone-system, stress axis and peripheral and coronary vasculature. Adequate experimental or human studies examining the consequences for cerebrovascular, cognitive and mental disorders are unavailable.

TLR2-Deficiency Promotes Prenatal LPS Exposure-Induced Offspring Hyperlipidemia

Toll-like receptor 2 (TLR2), which recognizes several lipopeptides and transduces inflammatory signaling, promotes the pathogenesis of diet-induced dyslipidemia and obesity. TLR2-deficient mice were shown to have improved insulin sensitivity and reduced diet-induced metabolic syndrome. Previous studies demonstrated that prenatal lipopolysaccharide (LPS) exposure causes dyslipidemia accompanied by increased body weight and insulin resistance in offspring. To determine whether TLRs are involved in this complex abnormal phenotype, we analyzed TLR2 and TLR4 expression levels in adipose tissues from offspring with prenatal LPS-exposure (offspring-pLPS) and compared these levels to those of control offspring with prenatal saline-exposure (offspring-pSaline). TLR2 expression was specifically upregulated in the adipose tissue of offspring-pLPS mice. However, unexpectedly, TLR2-deficient offspring-pLPS mice not only presented with an abnormal phenotype comparable to that of wild-type offspring-pLPS mice but also exhibited significantly more severe hyperlipidemia. Our further analyses revealed a dramatic upregulation of TLR4 expression and overactivation of the TLR4/Myd88 signaling pathway in TLR2-deficient offspring-pLPS adipose tissue. Our finding suggests a compensatory genetic interaction between TLR2 and TLR4 in the context of prenatal inflammatory stimulation, and this interaction likely contributes to the prenatal inflammation-induced hyperlipidemia and lipid overload-induced obesity, thus providing a potential mechanism for the fetal origin of adult metabolic diseases.

Endothelial PPARγ (Peroxisome Proliferator-Activated Receptor-γ) Protects From Angiotensin II-Induced Endothelial Dysfunction in Adult Offspring Born From Pregnancies Complicated by Hypertension

Preeclampsia is a hypertensive disorder of pregnancy associated with vascular dysfunction and cardiovascular risk to offspring. We hypothesize that endothelial PPARγ (peroxisome proliferator-activated receptor-γ) provides cardiovascular protection in offspring from pregnancies complicated by hypertension. C57BL/6J dams were bred with E-V290M sires, which express a dominant-negative allele of PPARγ selectively in the endothelium. Arginine vasopressin was infused throughout gestation. Vasopressin elevated maternal blood pressure at gestational day 14 to 15 and urinary protein at day 17 consistent. Systolic blood pressure and vasodilation responses to acetylcholine were similar in vasopressin-exposed offspring compared to offspring from control pregnancies. We treated offspring with a subpressor dose of angiotensin II to test if hypertension during pregnancy predisposes offspring to hypertension. Male and female angiotensin II-treated E-V290M offspring from vasopressin-exposed but not control pregnancy exhibited significant impairment in acetylcholine-induced relaxation in carotid artery. Endothelial dysfunction in angiotensin II-treated E-V290M vasopressin-exposed offspring was attenuated by tempol, an effect which was more prominent in male offspring. Nrf2 (nuclear factor-E2-related factor) protein levels were significantly elevated in aorta from male E-V290M offspring, but not female offspring compared to controls. Blockade of ROCK (Rho-kinase) signaling and incubation with a ROCK2-specific inhibitor improved endothelial function in both male and female E-V290M offspring from vasopressin-exposed pregnancy. Our data suggest that interference with endothelial PPARγ in offspring from vasopressin-exposed pregnancies increases the risk for endothelial dysfunction on exposure to a cardiovascular stressor in adulthood. This implies that endothelial PPARγ provides protection to cardiovascular stressors in offspring of a pregnancy complicated by hypertension and perhaps in preeclampsia.

Prevention: From the cradle to the grave and beyond

Present cardiac prevention mainly focuses on risk reduction later in life, and focuses also mainly on reducing risk factors for coronary heart disease. However, multiple studies have gathered evidence that the development risk of cardiovascular disease starts early in life and that even preconceptional influences play an important role in lifetime risk. Therefore, the importance of well-timed prevention strategies to reduce cardiovascular disease is well established. In this article, we discuss different risk factors for future cardiac disease, and how we can respond to lesser known cardiac risk factors in the different stages of life.

Atrial and ventricular ejection force of the fetal heart: Which of the four chambers is the dominant?

Background/Aim:

This study aimed to measure and compare the ejection force of the cardiac chambers in healthy singleton fetuses and to investigate the relationship of ejection force of cardiac chambers with gestational age, fetal sex, and fetal heart rate.

Patients and Methods:

A prospective study was performed on 68 singleton fetuses with a gestational age of 17–34 weeks. Atrial and ventricular ejection force was measured. Measurements were repeated in 18 of the fetuses to assess intraobserver reliability.

Results:

The right atrium had the highest ejection force of all the cardiac chambers. Ejection force of both atria and ventricles increased with gestational age.

Conclusion:

The right atrium is the dominant chamber of the fetal heart in 17–34 weeks of gestation. Comparison of our values with previous studies indicates that left atrial ejection force almost doubles in the 1^st month after birth. This study highlights the crucial role of the right atrium in the fetal cardiac function during 17–34 weeks of gestation.

A rat model to study maternal depression during pregnancy and postpartum periods, its comorbidity with cardiovascular diseases and neurodevelopmental impact in the offspring

This study aimed to develop an animal model of human depression during pregnancy and lactation to examine the effect of maternal, perinatal depression on offspring development. Maternal depression during pregnancy affects up to 20% of women and is a risk factor for both the developmental and long-term health issues. It is often comorbid with the cardiovascular disease (CVD) that affects the uteroplacental circulation and impacts offspring development. More than half of the expecting mothers with depression use antidepressants that cross the placenta and may interfere with the neurodevelopmental programming. Thus, depressed pregnant mothers face a difficult choice whether "to use or not to use" antidepressant therapy, since both untreated depression and antenatal antidepressant exposure present increased risks of neurodevelopmental pathologies. The ongoing clinical debate presents inconclusive data, while the existing animal models of maternal depression do not include early gestational periods, and, do not monitor depressive-like behavior nor address the cardiovascular abnormalities. The presented model includes pregestational depressive behavior extending into pregnancy and lactation, periods that have not been previously examined. Rat dams exposed to pre-gestational chronic mild stress (CMS) developed a sustained decrease in self-grooming behavior, correlated with hormonal, behavioral, and cardiac changes persisting through the postpartum period. Preliminary data indicate neurodevelopmental delays, behavioral and cardiac abnormalities, and altered levels of both the brain and the heart markers in the offspring of stressed dams. Furthermore, the preliminary data predict that maternal pregnancy during the perinatal period is likely to impact the neurodevelopmental process in a sex-dependent manner. Thus the presented here model (PG-LAC CMS) fulfills both the face and the construct validity criteria for maternal stress-induced depression during pregnancy and postpartum that may facilitate further studies of the relative risks of untreated vs. antidepressant-treated maternal depression during pregnancy to the mother and her offspring.

Copenhagen Baby Heart Study: a population study of newborns with prenatal inclusion

Congenital heart diseases (CHDs) are reported in 0.8% of newborns. Numerous factors influence cardiovascular development and CHD prevalence, and possibly also development of cardiovascular disease later in life. However, known factors explain the probable etiology in only a fraction of patients. Past large-scale population-based studies have made invaluable contributions to the understanding of cardiac disease, but none recruited participants prenatally and focused on the neonatal period. The Copenhagen Baby Heart Study (CBHS) is a population-based study of the prevalence, spectrum, and prognosis of structural and functional cardiac abnormalities. The CBHS will also establish normal values for neonatal cardiac parameters and biomarkers, and study prenatal and early childhood factors potentially affecting later cardiovascular disease risk. The CBHS is an ongoing multicenter, prospective study recruiting from second trimester pregnancy (gestational weeks 18-20) (expected n = 25,000). Information on parents, pregnancy, and delivery are collected. After birth, umbilical cord blood is collected for biochemical analysis, DNA purification, and biobank storage. An echocardiographic examination, electrocardiography, and post-ductal pulse oximetry are performed shortly after birth. Infants diagnosed with significant CHD are referred to a specialist or admitted to hospital, depending on CHD severity. CBHS participants will be followed prospectively as part of specific research projects or regular clinical follow-up for CHD. CBHS design and methodology are described. The CBHS aims to identify new mechanisms underlying cardiovascular disease development and new targets for prevention, early detection, and management of CHD and other cardiac diseases presenting at birth or developing later in life.

Correlates of elevated blood pressure in healthy children: a systematic review

The prevalence of hypertension in children is increasing globally. Addressing this will require a robust understanding of associated risk factors. To this end, we conducted a systematic review to identify correlates of elevated blood pressure (BP) in children. Literature searches were conducted using pre-defined search terms from three academic databases. The abstract and full text of identified studies were screened for eligibility by two independent reviewers. A total of 100 studies were included in this systematic review. An assessment tool was first used to assess study quality; a narrative synthesis was then performed. We found a broad range of physiological, social and behavioural factors associated with elevated BP in children. The most common correlate observed was adiposity, suggesting that childhood obesity may be implicated in the increased prevalence of hypertension observed in children. However, the broad range of other factors identified underscores the multi-factorial aetiology of hypertension. Data from a broad range of studies showed that the correlates of hypertension in children are multi-factorial. Therefore, approaches aimed at preventing hypertension must in turn be multi-factorial to ensure that the burden of hypertension in childhood is addressed.

High-fat diet reduces weight gain but increases other cardio-metabolic indices in offspring of normotensive and hypertensive rats

This study investigated the effect of post-natal consumption of high-fat diet (HFD) on cardio-metabolic indices in male offspring of hypertensive female rats. There were neither significant differences in body weight gain either in pups from normotensive or hypertensive dams that received normal diet during the post-weaning periods (except at 7th and 9th weeks), nor in both pup groups that received HFD. However, both pup groups that received HFD had reduced body weight gain when compared to their counterparts that received normal diet. Post-weaning administration of HFD to pups of hypertensive and normotensive dams significantly increased their blood glucose, pressure and lipid profiles when compared to those weaned to normal diet. It was concluded that male offspring consumption of HFD diet elicits cardio-metabolic disturbance that slightly depended of maternal cardiovascular status but majorly depended on post-weaning weight gain, while that elicited by maternal hypertension is not related to post-weaning weight gain.

Milk cholesterol concentration in mice is not affected by high cholesterol diet- or genetically-induced hypercholesterolaemia

Breast milk cholesterol content may imply to affect short- and long-term cholesterol homeostasis in the offspring. However, mechanisms of regulating milk cholesterol concentration are only partly understood. We used different mouse models to assess the impact of high cholesterol diet (HC)- or genetically-induced hypercholesterolaemia on milk cholesterol content. At day 14 postpartum we determined milk, plasma and tissue lipids in wild type (WT), LDL receptor knockout (Ldlr−/−), and ATP-binding cassette transporter G8 knockout (Abcg8−/−) mice fed either low- or 0.5% HC diet. In chow-fed mice, plasma cholesterol was higher in Ldlr−/− dams compared to WT. HC-feeding increased plasma cholesterol in all three models compared to chow diet. Despite the up to 5-fold change in plasma cholesterol concentration, the genetic and dietary conditions did not affect milk cholesterol levels. To detect possible compensatory changes, we quantified de novo cholesterol synthesis in mammary gland and liver, which was strongly reduced in the various hypercholesterolaemic conditions. Together, these data suggest that milk cholesterol concentration in mice is not affected by conditions of maternal hypercholesterolaemia and is maintained at stable levels via ABCG8- and LDLR-independent mechanisms. The robustness of milk cholesterol levels might indicate an important physiological function of cholesterol supply to the offspring.

Maternal supraphysiological hypercholesterolemia associates with endothelial dysfunction of the placental microvasculature

Maternal physiological or supraphysiological hypercholesterolemia (MPH, MSPH) occurs during pregnancy. MSPH is associated with foetal endothelial dysfunction and atherosclerosis. However, the potential effects of MSPH on placental microvasculature are unknown. The aim of this study was to determine whether MSPH alters endothelial function in the placental microvasculature both ex vivo in venules and arterioles from the placental villi and in vitro in primary cultures of placental microvascular endothelial cells (hPMEC). Total cholesterol < 280 mg/dL indicated MPH, and total cholesterol ≥280 mg/dL indicated MSPH. The maximal relaxation to histamine, calcitonin gene-related peptide and adenosine was reduced in MSPH venule and arteriole rings. In hPMEC from MSPH placentas, nitric oxide synthase (NOS) activity and L-arginine transport were reduced without changes in arginase activity or the protein levels of endothelial NOS (eNOS), human cationic amino acid 1 (hCAT-1), hCAT-2A/B or arginase II compared with hPMEC from MPH placentas. In addition, it was shown that adenosine acts as a vasodilator of the placental microvasculature and that NOS is active in hPMEC. We conclude that MSPH alters placental microvascular endothelial function via a NOS/L-arginine imbalance. This work also reinforces the concept that placental endothelial cells from the macro- and microvasculature respond differentially to the same pathological condition.

Association of Maternal Prepregnancy Dyslipidemia With Adult Offspring Dyslipidemia in Excess of Anthropometric, Lifestyle, and Genetic Factors in the Framingham Heart Study

IMPORTANCE

Dyslipidemia in young adults in the United States during their childbearing years is common, and the consequences for the next generation are poorly understood. Further understanding of the harmful consequences of elevated low-density lipoprotein cholesterol (LDL-C) levels in young adults may help to inform population screening and management strategies.

OBJECTIVE

To examine whether adult levels of serum LDL-C are associated with maternal prepregnancy LDL-C levels beyond that attributable to inherited genetic sequence polymorphisms, diet, physical activity, and body mass index.

DESIGN, SETTING, AND PARTICIPANTS

The Framingham Heart Study is a multigenerational, population-based inception cohort initiated in 1948 in Framingham, Massachusetts. In this study of families, the analyses included 538 parent-offspring pairs with parental LDL-C levels measured in the study prior to the offspring's birth. Parental prebirth, parental concurrent, and adult offspring assessments occurred in 1971-1983, 1998-2001, and 2002-2005, respectively. Data analyses were conducted between March 1, 2013, and May 30, 2015.

EXPOSURES

Maternal prepregnancy LDL-C levels compared with paternal prepregnancy and parental concurrent LDL-C levels in association with adult offspring LDL-C levels.

MAIN OUTCOMES AND MEASURES

Adult offspring LDL-C levels were examined as both a continuous and dichotomous outcome (using a threshold of 130 mg/dL).

RESULTS

Among the 538 parent-offspring pairs, there were 241 mother-offspring and 297 father-offspring pairs with a mean (SD) offspring age of 26 (3) years. Adult offspring LDL-C levels were associated with maternal prepregnancy LDL-C levels after adjustment for family relatedness and offspring lifestyle, anthropometric factors, and inherited genetic variants (β = 0.32 [SE, 0.05] mg/dL; P < .001). After multivariable adjustment, adults who had been exposed to elevated maternal prepregnancy LDL-C levels were at a 3.8 (95% CI, 1.5-9.8) times higher odds of having elevated LDL-C levels (P = .005) and had an adjusted LDL-C level of 18 mg/dL (95% CI, 9-27 mg/dL) higher than did those without such exposure. Maternal prepregnancy LDL-C levels explained 13% of the variation in adult offspring LDL-C levels beyond common genetic variants and classic risk factors for elevated LDL-C levels.

CONCLUSIONS AND RELEVANCE

Adult offspring dyslipidemia is associated with maternal prepregnancy dyslipidemia in excess of measured lifestyle, anthropometric, and inherited genetic factors. The findings support the possibility of a maternal epigenetic contribution to cardiovascular disease risk in the general population. Further research is warranted to determine whether ongoing public health efforts to identify and reduce dyslipidemia in young adults prior to their childbearing years may have additional potential health benefits for the subsequent generation.

Marine Omega-3 Fatty Acids, Complications of Pregnancy and Maternal Risk Factors for Offspring Cardio-Metabolic Disease

Marine omega-3 polyunsaturated fatty acids (n-3 PUFA) are important nutrients during periods of rapid growth and development in utero and infancy. Maternal health and risk factors play a crucial role in birth outcomes and subsequently offspring cardio-metabolic health. Evidence from observational studies and randomized trials have suggested a potential association of maternal intake of marine n-3 PUFAs during pregnancy with pregnancy and birth outcomes. However, there is inconsistency in the literature on whether marine n-3 PUFA supplementation during pregnancy can prevent maternal complications of pregnancy. This narrative literature review summarizes recent evidence on observational and clinical trials of marine n-3 PUFA intake on maternal risk factors and effects on offspring cardio-metabolic health. The current evidence generally does not support a role of maternal n-3 PUFA supplementation in altering the incidence of gestational diabetes, pregnancy-induced hypertension, or pre-eclampsia. It may be that benefits from marine n-3 PUFA supplementation are more pronounced in high-risk populations, such as women with a history of complications of pregnancy, or women with low marine n-3 PUFA intake. Discrepancies between studies may be related to differences in study design, dosage, fatty acid interplay, and length of treatment. Further prospective double-blind studies are needed to clarify the impact of long-chain marine n-3 PUFAs on risk factors for cardio-metabolic disease in the offspring.

The effect of sex and prematurity on the cardiovascular baroreflex response in sheep

NEW FINDINGS

What is the central question of this study? Late preterm infants are often assumed to escape long-term morbidities known to impact earlier preterm offspring. Is this true for the cardiovascular system? What is the main finding and its importance? We show that late preterm birth is a risk factor for cardiovascular dysfunction in early adulthood and is influenced by sex. Early signs of cardiovascular dysfunction might predispose to heart disease in adulthood. Very preterm infants have an increased risk of cardiovascular disease; however, the effects of a late preterm birth on future cardiovascular function are not known. We hypothesized that after a late preterm birth, the well-described impairments in heart rate variability and baroreflex sensitivity would persist into adulthood. To test this hypothesis, sheep born preterm (0.9 gestation; nine male and seven female) or term (11 male and six female) underwent surgery at 14 months of age for insertion of femoral arterial and venous catheters and a femoral flow probe. After recovery, heart rate variability was assessed, followed by a baroreflex challenge (using the vasoactive agents phenylephrine and sodium nitroprusside) in conscious adult lambs. Our data demonstrate decreased low-frequency normalised units (LFnu) and low-frequency/high-frequency ratio in female but not male ex-preterm sheep at rest. When challenged, mature male ex-preterm sheep have an increased blood pressure response but dampened heart rate baroreflex response. We show that even a late preterm birth leads to cardiovascular dysfunction in adulthood. These early signs of cardiovascular dysfunction might underpin the later hypertension and increased risk of heart disease observed in adults born preterm. These findings are particularly important because late preterm infants are often assumed to escape the long-term morbidities known to impact on very preterm and extremely preterm offspring.

Perinatal Hypercholesterolemia Exacerbates Atherosclerosis Lesions in Offspring by Altering Metabolism of Trimethylamine-N-Oxide and Bile Acids

OBJECTIVE

Experimental studies suggest that maternal hypercholesterolemia may be relevant for the early onset of cardiovascular disease in offspring. We investigated the effect of perinatal hypercholesterolemia on the atherosclerosis development in the offspring of apolipoprotein E-deficient mice and the underlying mechanism.

APPROACH AND RESULTS

Atherosclerosis and related parameters were studied in adult male or female apolipoprotein E-deficient mice offspring from either normocholesterolemic or hypercholesterolemic mothers and normocholesterolemic fathers. Female born to hypercholesterolemic mothers had more aortic root lesions than female born to normocholesterolemic mothers. Lesions in whole aorta did not differ between groups. Higher trimethylamine-N-oxide levels and Fmo3 hepatic gene expression were higher in female born to hypercholesterolemic mothers offspring compared with female born to normocholesterolemic mothers and male. Trimethylamine-N-oxide levels were correlated with the size of atherosclerotic root lesions. Levels of hepatic cholesterol and gallbladder bile acid were greater in male born to hypercholesterolemic mothers compared with male born to normocholesterolemic mothers. At 18 weeks of age, female born to hypercholesterolemic mothers showed lower hepatic Scarb1 and Cyp7a1 but higher Nr1h4 gene expression compared with female born to normocholesterolemic mothers. Male born to hypercholesterolemic mothers showed an increase in Scarb1 and Ldlr gene expression compared with male born to normocholesterolemic mothers. At 25 weeks of age, female born to hypercholesterolemic mothers had lower Cyp7a1 gene expression compared with female born to normocholesterolemic mothers. DNA methylation of Fmo3, Scarb1, and Ldlr promoter regions was slightly modified and may explain the mRNA expression modulation.

CONCLUSIONS

Our findings suggest that maternal hypercholesterolemia may exacerbate the development of atherosclerosis in female offspring by affecting metabolism of trimethylamine-N-oxide and bile acids. These data could be explained by epigenetic alterations.

Histological changes in the umbilical artery following severe chorioamnionitis and funisitis may be indicative of early atherosclerosis

We investigated whether histological evidence of early atherosclerosis was present in the umbilical artery of 21 pregnancies complicated by severe perinatal inflammation, and 21 controls matched for gestational age, sex and birth weight. Severe chorioamnionitis with funisitis was associated with increased numbers of CD68 and CD45 positive cells (both P < 0.01), indicating accumulation of monocyte-derived macrophages in lesion-susceptible regions. A down-regulation of SMA expression (P = 0.01) was also observed. These preliminary findings suggest that chorioamnionitis with funisitis may promote changes in the intima and media of the umbilical artery similar to that seen in early atherosclerosis.

Sustained elevation of NF-κB activity sensitizes offspring of maternal inflammation to hypertension via impairing PGC-1α recovery

Growing evidence has demonstrated that maternal detrimental factors, including inflammation, contribute to the development of hypertension in the offspring. The current study found that offspring subjected to prenatal exposure of inflammation by lipopolysaccharide (LPS) challenge during the second semester showed significantly increased systolic blood pressure. In addition, these offspring also displayed augmented vascular damage and reactive oxygen species (ROS) levels in thoracic aortas when challenged with deoxycorticosterone acetate and high-salt diet (DOCA-salt). Interestingly, the antioxidant N-acetyl-L-cysteine markedly reversed these changes. Mechanistically, prenatal LPS exposure led to pre-existing elevated peroxisome proliferators-activated receptor-γ co-activator (PGC)-1α, a critical master of ROS metabolism, which up-regulated the ROS defense capacity and maintained the balance of ROS generation and elimination under resting state. However, continued elevation of NF-κB activity significantly suppressed the rapid recovery of PGC-1α expression response to DOCA-salt challenge in offspring that underwent prenatal inflammatory stimulation. This was further confirmed by using a NF-κB inhibitor (N-p-Tosyl-L-phenylalanine chloromethyl ketone) that restored PGC-1α recovery and prevented blood pressure elevation induced by DOCA-salt. Our results suggest that maternal inflammation programmed proneness to NF-κB over-activation which impaired PGC-1α-mediated anti-oxidant capacity resulting in the increased sensitivity of offspring to hypertensive damage.

Maternal inflammation activated ROS-p38 MAPK predisposes offspring to heart damages caused by isoproterenol via augmenting ROS generation

Maternal inflammation contributes to the increased incidence of adult cardiovascular disease. The current study investigated the susceptibility of cardiac damage responding to isoproterenol (ISO) in adult offspring that underwent maternal inflammation (modeled by pregnant Sprague-Dawley rats with lipopolysaccharides (LPS) challenge). We found that 2 weeks of ISO treatment in adult offspring of LPS-treated mothers led to augmented heart damage, characterized by left-ventricular systolic dysfunction, cardiac hypertrophy and myocardial fibrosis. Mechanistically, prenatal exposure to LPS led to up-regulated expression of nicotinamide adenine dinucleotide phosphate (NADPH) oxidases, antioxidant enzymes, and p38 MAPK activity in left ventricular of adult offspring at resting state. ISO treatment exaggerated ROS generation, p38 MAPK activation but down-regulated reactive oxygen species (ROS) elimination capacity in the left ventricular of offspring from LPS-treated mothers, while antioxidant N-acetyl-L-cysteine (NAC) reversed these changes together with improved cardiac functions. The p38 inhibitor SB202190 alleviated the heart damage only via inhibiting the expression of NADPH oxidases. Collectively, our data demonstrated that prenatal inflammation programs pre-existed ROS activation in the heart tissue, which switches on the early process of oxidative damages on heart rapidly through a ROS-p38 MAPK-NADPH oxidase-ROS positive feedback loop in response to a myocardial hypertrophic challenge in adulthood.

Inflammation, lipids and aortic intima-media thickness in newborns following chorioamnionitis

AIM

This study investigated whether chorioamnionitis was associated with increased inflammation, dyslipidaemia and adverse cardiovascular phenotypes in the immediate postnatal period.

METHODS

This prospective case-control study included preterm infants (30(+0) -35(+6) weeks gestational age, GA) whose mothers did not have pregnancy-related conditions that may influence outcomes. Chorioamnionitis was diagnosed by placental histology, and infants were divided retrospectively into cases (chorioamnionitis-exposed) and controls (unexposed). Serum high-sensitivity C-reactive protein (hsCRP), lipid profile, far-wall abdominal aortic intima-media thickness (aIMT) and blood pressure (BP) were measured in the first week of life.

RESULTS

There were 20 (16 male, mean GA 32.4 weeks) cases and 31 (12 male, mean GA 32.6 weeks) controls. Histological chorioamnionitis was associated with a significant increase in hsCRP and a non-significant trend towards an adverse lipid profile. There was no evidence of differences in aIMT or BP.

CONCLUSION

Preterm infants exposed to chorioamnionitis have greater postnatal inflammation. There were no early postnatal differences in aIMT or BP. The inflammatory stimulus of chorioamnionitis late in gestation may be of insufficient intensity and duration to result in immediate postnatal alterations to arterial structure. Cardiovascular follow-up of infants exposed to chorioamnionitis may identify differential risk trajectories and subsequent inflammatory responses.

Post-Natal Inhibition of NF-κB Activation Prevents Renal Damage Caused by Prenatal LPS Exposure

Prenatal exposure to an inflammatory stimulus has been shown to cause renal damage in offspring. Our present study explored the role of intra-renal NF-κB activation in the development of progressive renal fibrosis in offspring that underwent prenatal exposure to an inflammatory stimulus. Time-dated pregnant rats were treated with saline (control group) or 0.79 mg/kg lipopolysaccharide (LPS) through intra-peritoneal injection on gestational day 8, 10 and 12. At the age of 7 weeks, offspring from control or LPS group were treated with either tap water (Con+Ve or LPS+Ve group) or pyrollidine dithiocarbamate (PDTC, 120mg/L), a NF-κB inhibitor, via drinking water starting (Con+PDTC or LPS+PDTC group), respectively, till the age of 20 or 68 weeks. The gross structure of kidney was assessed by hematoxylin-eosin, periodic acid–Schiff staining and Sirius red staining. The expression levels of TNF-α, IL-6, α-smooth muscle actin (α-SMA) and renin-angiotensin system (RAS) genes were determined by real time polymerase chain reaction and/or immunohistochemical staining. Our data showed that post-natal persistent PDTC administration efficiently repressed intra-renal NF-κB activation, TNF-α and IL-6 expression. Post-natal PDTC also prevented intra-renal glycogen deposition and collagenous fiber generation as evident by the reduced expression of collagen III and interstitial α-SMA in offspring of prenatal LPS exposure. Furthermore, post-natal PDTC administration reversed the intra-renal renin-angiotensin system (RAS) over-activity in offspring of prenatal LPS exposure. In conclusion, prenatal inflammatory exposure results in offspring’s intra-renal NF-κB activation along with inflammation which cross-talked with excessive RAS activation that caused exacerbation of renal fibrosis and dysfunction in the offspring. Thus, early life prevention of NF-κB activation may be a potential preventive strategy for chronic renal inflammation and progressive renal damage.

Dyslipidemia in Pregnancy

"Recent studies have revealed evidence that poorly controlled cholesterol, triglycerides, and their metabolites during pregnancy may be associated with cardiometabolic dysfunction and have significant detrimental fetal and maternal vascular consequences. Cardiometabolic dysfunction during pregnancy may not only contribute to long-term effects of the mother and child's vascular health but also potentially create cardiovascular risk for generational offspring. This article provides updates on this rapidly expanding and multifaceted topic and reviews new insight regarding why recognition of this disordered maternal cholesterol and triglyceride metabolism is likely to have long-term effect on the increasing atherosclerotic burden of the burgeoning population."

Role for Tetrahydrobiopterin in the Fetoplacental Endothelial Dysfunction in Maternal Supraphysiological Hypercholesterolemia

Maternal physiological hypercholesterolemia occurs during pregnancy, ensuring normal fetal development. In some cases, the maternal plasma cholesterol level increases to above this physiological range, leading to maternal supraphysiological hypercholesterolemia (MSPH). This condition results in endothelial dysfunction and atherosclerosis in the fetal and placental vasculature. The fetal and placental endothelial dysfunction is related to alterations in the L-arginine/nitric oxide (NO) pathway and the arginase/urea pathway and results in reduced NO production. The level of tetrahydrobiopterin (BH4), a cofactor for endothelial NO synthase (eNOS), is reduced in nonpregnant women who have hypercholesterolemia, which favors the generation of the superoxide anion rather than NO (from eNOS), causing endothelial dysfunction. However, it is unknown whether MSPH is associated with changes in the level or metabolism of BH4; as a result, eNOS function is not well understood. This review summarizes the available information on the potential link between MSPH and BH4 in causing human fetoplacental vascular endothelial dysfunction, which may be crucial for understanding the deleterious effects of MSPH on fetal growth and development.

Associations of blood pressure in pregnancy with offspring blood pressure trajectories during childhood and adolescence: findings from a prospective study

Background

Hypertensive disorders of pregnancy are related to higher offspring blood pressure (BP), but it is not known whether this association strengthens or weakens as BP changes across childhood. Our aim was to assess the associations of hypertensive disorders of pregnancy and maternal BP changes during pregnancy with trajectories of offspring BP from age 7 to 18 years.

Methods and Results

In a large UK cohort of maternal–offspring pairs (N=6619), we used routine antenatal BP measurements to derive hypertensive disorders of pregnancy and maternal BP trajectories. These were related to offspring BP trajectories, obtained from research clinic assessments, using linear spline random-effects models. After adjusting for maternal and offspring variables, including body mass index, offspring of women who had existing hypertension, gestational hypertension, or preeclampsia during pregnancy had on average higher BP at age 7 years compared to offspring of normotensive pregnancies (mean difference [95%CI] in systolic BP: 1.67 mm Hg [0.48, 2.86], 1.98 mm Hg [1.32, 2.65], and 1.22 mm Hg [−0.52, 2.97], respectively). These differences were consistent across childhood to age 18 years, as the patterns of BP change did not differ between offspring of hypertensive pregnancies and normotensive pregnancies. Maternal BP at 8 weeks’ gestation was also positively associated with offspring BP in childhood and adolescence, but changes in BP across pregnancy were not strongly associated.

Conclusions

The differences in BP between offspring of hypertensive pregnancies and offspring of normotensive pregnancies remain consistent across childhood and adolescence. These associations appear to be most contributed to by higher maternal BP in early pregnancy rather than by pregnancy-related BP changes.