Intrauterine growth restriction-induced deleterious adaptations in endothelial progenitor cells: possible mechanism to impair endothelial function

Abnormal epigenetic memory of mesenchymal stem and progenitor cells caused by fetal malnutrition induces hypertension and renal injury in adulthood

Fetal malnutrition has been reported to induce hypertension and renal injury in adulthood. We hypothesized that this hypertension and renal injury would be associated with abnormal epigenetic memory of stem and progenitor cells contributing to organization in offspring due to fetal malnutrition. We measured blood pressure (BP) for 60 weeks in offspring of pregnant rats fed a normal protein diet (Control), low-protein diet (LP), and LP plus taurine (LPT) in the fetal period. We used western blot analysis to evaluate the expression of αSMA and renin in CD44-positive renal mesenchymal stem cells (MSCs) during differentiation by TGF-β1. We measured kidney label-retaining cells (LRCs) at 11 weeks of age and formation of endothelial progenitor cells (EPCs) at 60 weeks of age from the offspring with fetal malnutrition. Epigenetics of the renal MSCs at 14 weeks were investigated by ATAC-sequence and RNA-sequence analyses. BP was significantly higher in LP than that in Control and LPT after 45-60 weeks of age. Numbers of LRCs and EPC colonies were significantly lower in LP than in Control. Renal MSCs from LP already showed expression of h-caldesmon, αSMA, LXRα, and renin before their differentiation. Epigenetic analyses identified PAR2, Chac1, and Tspan6 genes in the abnormal differentiation of renal MSCs. These findings suggested that epigenetic abnormalities of stem and progenitor cell memory cause hypertension and renal injury that appear in adulthood of offspring with fetal malnutrition.

Endothelial progenitor cells in pregnancy-related diseases

Placental neovascularization plays a crucial role in fetomaternal circulation throughout pregnancy and is dysregulated in several pregnancy-related diseases, including preeclampsia, gestational diabetes mellitus, and fetal growth restriction. Endothelial progenitor cells (EPCs) are a heterogeneous population of cells that differentiate into mature endothelial cells, which influence vascular homeostasis, neovascularization, and endothelial repair. Since their discovery in 1997 by Asahara et al., the role of EPCs in vascular biology has garnered a lot of interest. However, although pregnancy-related conditions are associated with changes in the number and function of EPCs, the reported findings are conflicting. This review discusses the discovery, isolation, and classification of EPCs and highlights discrepancies between current studies. Overviews of how various diseases affect the numbers and functions of EPCs, the role of EPCs as biomarkers of pregnancy disorders, and the potential therapeutic applications involving EPCs are also provided.

Pathomechanisms of Prenatally Programmed Adult Diseases

Based on epidemiological observations Barker et al. put forward the hypothesis/concept that an adverse intrauterine environment (involving an insufficient nutrient supply, chronic hypoxia, stress, and toxic substances) is an important risk factor for the development of chronic diseases later in life. The fetus responds to the unfavorable environment with adaptive reactions, which ensure survival in the short run, but at the expense of initiating pathological processes leading to adult diseases. In this review, the major mechanisms (including telomere dysfunction, epigenetic modifications, and cardiovascular-renal-endocrine-metabolic reactions) will be outlined, with a particular emphasis on the role of oxidative stress in the fetal origin of adult diseases.

Endothelial Colony-Forming Cells Dysfunctions Are Associated with Arterial Hypertension in a Rat Model of Intrauterine Growth Restriction

Infants born after intrauterine growth restriction (IUGR) are at risk of developing arterial hypertension at adulthood. The endothelium plays a major role in the pathogenesis of hypertension. Endothelial colony-forming cells (ECFCs), critical circulating components of the endothelium, are involved in vasculo-and angiogenesis and in endothelium repair. We previously described impaired functionality of ECFCs in cord blood of low-birth-weight newborns. However, whether early ECFC alterations persist thereafter and could be associated with hypertension in individuals born after IUGR remains unknown. A rat model of IUGR was induced by a maternal low-protein diet during gestation versus a control (CTRL) diet. In six-month-old offspring, only IUGR males have increased systolic blood pressure (tail-cuff plethysmography) and microvascular rarefaction (immunofluorescence). ECFCs isolated from bone marrow of IUGR versus CTRL males displayed a decreased proportion of CD31+ versus CD146+ staining on CD45- cells, CD34 expression (flow cytometry, immunofluorescence), reduced proliferation (BrdU incorporation), and an impaired capacity to form capillary-like structures (Matrigel test), associated with an impaired angiogenic profile (immunofluorescence). These dysfunctions were associated with oxidative stress (increased superoxide anion levels (fluorescent dye), decreased superoxide dismutase protein expression, increased DNA damage (immunofluorescence), and stress-induced premature senescence (SIPS; increased beta-galactosidase activity, increased p16INK4a, and decreased sirtuin-1 protein expression). This study demonstrated an impaired functionality of ECFCs at adulthood associated with arterial hypertension in individuals born after IUGR.

Intrauterine growth restriction weakens anticontractile influence of NO in coronary arteries of adult rats

Intrauterine growth restriction (IUGR) is one of the most common pathologies of pregnancy. The cardiovascular consequences of IUGR do not disappear in adulthood and can manifest themselves in pathological alterations of vasomotor control. The hypothesis was tested that IUGR weakens anticontractile influence of NO and augments procontractile influence of Rho-kinase in arteries of adult offspring. To model IUGR in the rat, dams were 50% food restricted starting from the gestational day 11 till delivery. Mesenteric and coronary arteries of male offspring were studied at the age of 3 months using wire myography, qPCR, and Western blotting. Contractile responses of mesenteric arteries to α1-adrenoceptor agonist methoxamine as well as influences of NO and Rho-kinase did not differ between control and IUGR rats. However, coronary arteries of IUGR rats demonstrated elevated contraction to thromboxane A2 receptor agonist U46619 due to weakened anticontractile influence of NO and enhanced role of Rho-kinase in the endothelium. This was accompanied by reduced abundance of SODI protein and elevated content of RhoA protein in coronary arteries of IUGR rats. IUGR considerably changes the regulation of coronary vascular tone in adulthood and, therefore, can serve as a risk factor for the development of cardiac disorders.

Intrauterine growth restriction leads to a high-corticosterone producing offspring: An implication for pulmonary infection susceptibility

AIMS

Although intrauterine growth restriction (IUGR) impairs immune system homeostasis and lung development, its relationship with the susceptibility to pulmonary infections remains unclear. Thus, this study aimed to investigate the impact of IUGR on acute lung inflammatory response induced by bacterial stimulus.

MATERIALS AND METHODS

Pregnant female Wistar rats were subjected to 50% caloric-protein food restriction during gestation. To mimic bacterial lung infection, adult male offspring (12 weeks old) were challenged with a single lipopolysaccharide (LPS) intranasal instillation, and 6 h later, we assessed the acute inflammatory response. Normal birth weight (NBW) animals represent the control group.

KEY FINDINGS

LPS instillation increased the protein levels in the airways of both the NBW and low birth weight (LBW) groups, indicating vascular leakage. LBW animals exhibited a lower number of neutrophils, reduced production of interleukin-6 and macrophage-inflammatory protein-2 and decreased upregulation of intercellular adhesion molecule-1 gene expression in lung tissues. Further analysis revealed that the LBW group produced lower levels of prostaglandin-E₂ and failed to secrete leukotriene-B₄ upon LPS stimulation, which correlated with impaired cyclooxygenase-2 and 5-lipoxygenase expression. These results were probably associated with their inability to upregulate the expression of Toll-like receptor-4 and downstream signaling proteins, such as nuclear factor kappa-B, in the lungs. The LBW group also exhibited abnormal airway thickening and high corticosterone levels under basal conditions.

SIGNIFICANCE

This study suggests that IUGR-induced foetal programming in LBW offspring threatens HPA axis physiology and corticosterone biodisponibility, and impairs the innate response to bacterial antigens, increasing future susceptibility to pulmonary infection.

Developmental programming of cardiovascular function: a translational perspective

The developmental origins of health and disease (DOHaD) is a concept linking pre- and early postnatal exposures to environmental influences with long-term health outcomes and susceptibility to disease. It has provided a new perspective on the etiology and evolution of chronic disease risk, and as such is a classic example of a paradigm shift. What first emerged as the 'fetal origins of disease', the evolution of the DOHaD conceptual framework is a storied one in which preclinical studies played an important role. With its potential clinical applications of DOHaD, there is increasing desire to leverage this growing body of preclinical work to improve health outcomes in populations all over the world. In this review, we provide a perspective on the values and limitations of preclinical research, and the challenges that impede its translation. The review focuses largely on the developmental programming of cardiovascular function and begins with a brief discussion on the emergence of the 'Barker hypothesis', and its subsequent evolution into the more-encompassing DOHaD framework. We then discuss some fundamental pathophysiological processes by which developmental programming may occur, and attempt to define these as 'instigator' and 'effector' mechanisms, according to their role in early adversity. We conclude with a brief discussion of some notable challenges that hinder the translation of this preclinical work.

Developmental programming of adult haematopoiesis system

The Barker hypothesis of 'foetal origin of adult diseases' has led to emphasize the concept of 'developmental programming', based on the crucial role of epigenetic factors. Accordingly, it has been demonstrated that parental adversity (before conception and during pregnancy) and foetal factors (i.e., hypoxia, malnutrition and placental insufficiency) permanently modify the physiological systems of the progeny, predisposing them to premature ageing and chronic disease during adulthood. Thus, an altered functionality of the endocrine, immune, nervous and cardiovascular systems is observed in the progeny. However, it remains to be understood whether the haematopoietic system itself also represents a portrait of foetal programming. Here, we provide evidence, reporting and discussing related theories, and results of studies described in the literature. In addition, we have outlined our opinions and suggest how it is possible to intervene to correct foetal mal-programming. Some pro-health interventions and recommendations are proposed, with the hope of guarantee the health of future generations and trying to combat the continuous increase in age-related diseases in human populations.

Intrauterine growth restriction - impact on cardiovascular diseases later in life

Intrauterine growth restriction (IUGR) is a fetal pathology which leads to increased risk for certain neonatal complications. Furthermore, clinical and experimental studies revealed that IUGR is associated with a significantly higher incidence of metabolic, renal and cardiovascular diseases (CVD) later in life. One hypothesis for the higher risk of CVD after IUGR postulates that IUGR induces metabolic alterations that then lead to CVD.This minireview focuses on recent studies which demonstrate that IUGR is followed by early primary cardiovascular alterations which may directly progress to CVD later in life.

Neonatal and Long-Term Consequences of Fetal Growth Restriction

BACKGROUND

Fetal Growth Restriction (FGR) is one of the most common noxious antenatal conditions in humans, inducing a substantial proportion of preterm delivery and leading to a significant increase in perinatal mortality, neurological handicaps and chronic diseases in adulthood. This review summarizes the current knowledge about the postnatal consequences of FGR, with a particular emphasis on the long-term consequences on respiratory, cardiovascular and neurological structures and functions.

RESULT AND CONCLUSION

FGR represents a global health challenge, and efforts are urgently needed to improve our understanding of the critical factors leading to FGR and subsequent insults to the developing organs.