Tumor necrosis factor-alpha (TNF-alpha) inhibits insulin-like growth factor-I (IGF-I) activities in human trophoblast cell cultures through IGF-I/insulin hybrid receptors

Obesity and gestational diabetes independently and collectively induce specific effects on placental structure, inflammation and endocrine function in a cohort of South African women

Maternal obesity and gestational diabetes mellitus (GDM) are associated with insulin resistance and health risks for mother and offspring. Obesity is also characterized by low-grade inflammation, which in turn, impacts insulin sensitivity. The placenta secretes inflammatory cytokines and hormones that influence maternal glucose and insulin handling. However, little is known about the effect of maternal obesity, GDM and their interaction, on placental morphology, hormones and inflammatory cytokines. In a South African cohort of non-obese and obese pregnant women with and without GDM, this study examined placental morphology using stereology, placental hormone and cytokine expression using real-time PCR, western blotting and immunohistochemistry, and circulating TNFα and IL-6 concentrations using ELISA. Placental expression of endocrine and growth factor genes was not altered by obesity or GDM. However, LEPTIN gene expression was diminished, syncytiotrophoblast TNFα immunostaining elevated and stromal and fetal vessel IL-6 staining reduced in the placenta of obese women in a manner that was partly influenced by GDM status. Placental TNFα protein abundance and maternal circulating TNFα concentrations were reduced in GDM. Both maternal obesity and, to a lesser extent, GDM were accompanied by specific changes in placental morphometry. Maternal blood pressure and weight gain and infant ponderal index were also modified by obesity and/or GDM. Thus, obesity and GDM have specific impacts on placental morphology and endocrine and inflammatory states that may relate to pregnancy outcomes. These findings may contribute to developing placenta-targeted treatments that improve mother and offspring outcomes, which is particularly relevant given increasing rates of obesity and GDM worldwide. KEY POINTS: Rates of maternal obesity and gestational diabetes (GDM) are increasing worldwide, including in low-middle income countries (LMIC). Despite this, much of the work in the field is conducted in higher-income countries. In a well-characterised cohort of South African women, this study shows that obesity and GDM have specific impacts on placental structure, hormone production and inflammatory profile. Moreover, such placental changes were associated with pregnancy and neonatal outcomes in women who were obese and/or with GDM. The identification of specific changes in the placenta may help in the design of diagnostic and therapeutic approaches to improve pregnancy and neonatal outcomes with particular significant benefit in LMICs.

Role of ADAM and ADAMTS Disintegrin and Metalloproteinases in Normal Pregnancy and Preeclampsia

Normal pregnancy (NP) involves intricate processes starting with egg fertilization, proceeding to embryo implantation, placentation and gestation, and culminating in parturition. These pregnancy-related processes require marked uteroplacental and vascular remodeling by proteolytic enzymes and metalloproteinases. A disintegrin and metalloproteinase (ADAM) and ADAM with thrombospondin motifs (ADAMTS) are members of the zinc-dependent family of proteinases with highly conserved protein structure and sequence homology, which include a pro-domain, and a metalloproteinase, disintegrin and cysteine-rich domain. In NP, ADAMs and ADAMTS regulate sperm-egg fusion, embryo implantation, trophoblast invasion, placental angiogenesis and spiral arteries remodeling through their ectodomain proteolysis of cell surface cytokines, cadherins and growth factors as well as their adhesion with integrins and cell-cell junction proteins. Preeclampsia (PE) is a serious complication of pregnancy characterized by new-onset hypertension (HTN) in pregnancy (HTN-Preg) at or after 20 weeks of gestation, with or without proteinuria. Insufficient trophoblast invasion of the uterine wall, inadequate expansive remodeling of the spiral arteries, reduced uteroplacental perfusion pressure, and placental ischemia/hypoxia are major initiating events in the pathogenesis of PE. Placental ischemia/hypoxia increase the release of reactive oxygen species (ROS), which lead to aberrant expression/activity of certain ADAMs and ADAMTS. In PE, abnormal expression/activity of specific ADAMs and ADAMTS that function as proteolytic sheddases could alter proangiogenic and growth factors, and promote the release of antiangiogenic factors and inflammatory cytokines into the placenta and maternal circulation leading to generalized inflammation, endothelial cell injury and HTN-Preg, renal injury and proteinuria, and further decreases in uteroplacental blood flow, exaggeration of placental ischemia, and consequently fetal growth restriction. Identifying the role of ADAMs and ADAMTS in NP and PE has led to a better understanding of the underlying molecular and vascular pathways, and advanced the potential for novel biomarkers for prediction and early detection, and new approaches for the management of PE.

Placental function in maternal obesity

Maternal obesity is associated with pregnancy complications and increases the risk for the infant to develop obesity, diabetes and cardiovascular disease later in life. However, the mechanisms linking the maternal obesogenic environment to adverse short- and long-term outcomes remain poorly understood. As compared with pregnant women with normal BMI, women entering pregnancy obese have more pronounced insulin resistance, higher circulating plasma insulin, leptin, IGF-1, lipids and possibly proinflammatory cytokines and lower plasma adiponectin. Importantly, the changes in maternal levels of nutrients, growth factors and hormones in maternal obesity modulate placental function. For example, high insulin, leptin, IGF-1 and low adiponectin in obese pregnant women activate mTOR signaling in the placenta, promoting protein synthesis, mitochondrial function and nutrient transport. These changes are believed to increase fetal nutrient supply and contribute to fetal overgrowth and/or adiposity in offspring, which increases the risk to develop disease later in life. However, the majority of obese women give birth to normal weight infants and these pregnancies are also associated with activation of inflammatory signaling pathways, oxidative stress, decreased oxidative phosphorylation and lipid accumulation in the placenta. Recent bioinformatics approaches have expanded our understanding of how maternal obesity affects the placenta; however, the link between changes in placental function and adverse outcomes in obese women giving birth to normal sized infants is unclear. Interventions that specifically target placental function, such as activation of placental adiponectin receptors, may prevent the transmission of metabolic disease from obese women to the next generation.

Relationship between dietary inflammatory index, hs-CRP level in the second trimester and neonatal birth weight: a cohort study

The aim of this study was to investigate whether diet plays a role in the effect of inflammation on birth weight. The normal pre-pregnancy body mass index and healthy single pregnant women without classical inflammatory were recruited at 16-20 weeks of pregnancy and provided blood sample to measure plasma high sensitive C-reactive protein (hs-CRP) level. The Dietary Inflammatory Index (DII) score was calculated by a three-day 24 h recall method, and a cohort of 307 eligible pregnant women was established. According to birth weight, the subjects were divided into three groups: normal birth weight (NBW) group, low birth weight (LBW) group, and high birth weight (HBW) group. The hs-CRP level and DII score were significantly different between NBW and LBW groups. The risk of higher hs-CRP in the pro-inflammatory dietary group was 1.89 times than the control group (95% CI: 1.05, 3.42). The risk of LBW with higher hs-CRP was 3.81 times than normal hs-CRP (95% CI: 1.26, 11.56). The risk of LBW in the pro-inflammatory dietary group was 10.44 times than in the anti-inflammatory dietary group (95%CI: 1.29, 84.61). The pro-inflammatory dietary in the second trimester affects the hs-CRP level, showing a positive correlation. And both of two factors increase the risk of LBW.

Control strategies in systemic metabolism

Metabolic control systems coordinate myriad processes across the cellular, tissue and organismal levels to optimize the allocation of limited supplies across multiple, often competing, metabolic demands. As such, the regulation of metabolism can be analysed from the perspective of the economic theory of supply and demand. Here, we discuss how such analyses can provide new insights into the logic of metabolic control. In particular, we suggest that, in addition to being subject to well-appreciated homeostatic control, metabolism is subject to supply-driven and demand-driven controls, each operated by a dedicated set of signals throughout various physiological states, including inflammation. Furthermore, we argue that systemic homeostasis is a derived feature that evolved from the control systems that monitor metabolic supply and demand.

Synergistic effects of tumor necrosis factor-α and insulin-like growth factor-I on survival of human trophoblast-derived BeWo cell line

OBJECTIVE

Trophoblast survival is regulated by cytokines and growth factors. While the pharmacological levels (10-100 ng/mL) of tumor necrosis factor (TNF)- α affect trophoblasts survival in vitro, the effects of the physiological levels (1-10 pg/mL) of TNF-α remain unknown. We investigated the effects of the physiological levels of TNF-α on proliferation and apoptosis of human trophoblast cells by using BeWo cells. Insulin-like growth factor (IGF)-I is also a potent regulator of trophoblast survival and has been known to exert synergistic effects with other hormones. The interaction of IGF-I and TNF-α on BeWo cells survival was also examined.

METHODS

After incubating BeWo under the presence of TNF-α (10-10⁵ pg/mL) and IGF-I (10² ng/mL), we assessed cell number by WST-1 assay and cell proliferation by BrdU uptake assay and immunocytochemistry with anti-Ki67 antibody. Apoptosis was evaluated by TUNEL assay and caspase-3, 8 activity assays.

RESULTS

Under the presence of IGF-I, cell number, BrdU uptake, and Ki-67 expression of BeWo were dose-dependently enhanced by low TNF-α (10-10² pg/mL), while no such effects were detected without IGF-I. Higher levels of TNF-α (10⁴-10⁵ pg/mL) showed inhibiting effects on cell number and cell proliferation. The number of TUNEL positive cells were decreased and caspase activities were suppressed by lower levels (10-10² pg/mL) of TNF-α and IGF-I independently. Higher levels of TNF-α (10⁴-10⁵ pg/mL) showed promoting effects on apoptosis irrespective of IGF-I.

CONCLUSION

The physiological levels of TNF-α and IGF-I had synergetic effects on enhancing cell proliferation and also independently inhibited apoptosis of Bewo cells.

ASAS-SSR Triennnial Reproduction Symposium: Looking Back and Moving Forward-How Reproductive Physiology has Evolved: Fetal origins of impaired muscle growth and metabolic dysfunction: Lessons from the heat-stressed pregnant ewe

Intrauterine growth restriction (IUGR) is the second leading cause of perinatal mortality and predisposes offspring to metabolic disorders at all stages of life. Muscle-centric fetal adaptations reduce growth and yield metabolic parsimony, beneficial for IUGR fetal survival but detrimental to metabolic health after birth. Epidemiological studies have reported that IUGR-born children experience greater prevalence of insulin resistance and obesity, which progresses to diabetes, hypertension, and other metabolic disorders in adulthood that reduce quality of life. Similar adaptive programming in livestock results in decreased birth weights, reduced and inefficient growth, decreased carcass merit, and substantially greater mortality rates prior to maturation. High rates of glucose consumption and metabolic plasticity make skeletal muscle a primary target for nutrient-sparing adaptations in the IUGR fetus, but at the cost of its contribution to proper glucose homeostasis after birth. Identifying the mechanisms underlying IUGR pathophysiology is a fundamental step in developing treatments and interventions to improve outcomes in IUGR-born humans and livestock. In this review, we outline the current knowledge regarding the adaptive restriction of muscle growth and alteration of glucose metabolism that develops in response to progressively exacerbating intrauterine conditions. In addition, we discuss the evidence implicating developmental changes in β adrenergic and inflammatory systems as key mechanisms for dysregulation of these processes. Lastly, we highlight the utility and importance of sheep models in developing this knowledge.

Momordica charantia extracts ameliorate insulin resistance by regulating the expression of SOCS-3 and JNK in type 2 diabetes mellitus rats

CONTEXT

Momordica charantia L. (Cucurbitaceae) has long been widely used as a traditional remedy for diabetes mellitus in some countries. However, detailed antidiabetic mechanisms are largely unknown.

OBJECTIVES

This study clarified the ameliorating effects of M. charantia ethanol extracts (MCE) on the insulin resistance in type 2 diabetes mellitus (T2DM) rats.

MATERIALS AND METHODS

T2DM rat model was established by high-fat diet and streptozotocin (STZ) injection. Diabetic rats were randomized into five groups: the model control group (n = 8) (common diet), the high-fat diet metformin (50 mg/kg/d), and the three-dose MCE (100, 200, and 400 mg/kg/d) groups (n = 8 each). After 8  weeks, the fasting serum glucose, insulin, TNF-α, and IL-6 were measured, and the relevant factors of glucose and insulin were monitored by glycogen dyeing, RT-PCR, and western blot, respectively.

RESULTS

The 8-week treatment of 400 mg/kg MCE significantly lowered body weight (330.1 versus 365.9 g), serum glucose (7.41 versus 16.63 mmol/L), insulin (12.06 versus 15.89 mIU/L), TNF-α (52.72 versus 81.83 ng/L), and IL-6 (104.81 versus 135.74 ng/L) in comparison with those of the diabetic control group (p < 0.05). It was the same for skeletal muscle glucose transporter 4 (GLUT-4) protein, and glycogen level, suppressor of cytokine signaling-3 (SOCS-3), c-Jun N-terminal kinase (JNK), and Akt expression at both protein and mRNA levels in liver (p < 0.05).

CONCLUSIONS

MCE can ameliorate insulin resistance in T2DM rats. This effect may be related to the regulation of mRNA and protein levels of SOCS-3 and JNK.

Insulin Receptor Isoforms in Physiology and Disease: An Updated View

The insulin receptor (IR) gene undergoes differential splicing that generates two IR isoforms, IR-A and IR-B. The physiological roles of IR isoforms are incompletely understood and appear to be determined by their different binding affinities for insulin-like growth factors (IGFs), particularly for IGF-2. Predominant roles of IR-A in prenatal growth and development and of IR-B in metabolic regulation are well established. However, emerging evidence indicates that the differential expression of IR isoforms may also help explain the diversification of insulin and IGF signaling and actions in various organs and tissues by involving not only different ligand-binding affinities but also different membrane partitioning and trafficking and possibly different abilities to interact with a variety of molecular partners. Of note, dysregulation of the IR-A/IR-B ratio is associated with insulin resistance, aging, and increased proliferative activity of normal and neoplastic tissues and appears to sustain detrimental effects. This review discusses novel information that has generated remarkable progress in our understanding of the physiology of IR isoforms and their role in disease. We also focus on novel IR ligands and modulators that should now be considered as an important strategy for better and safer treatment of diabetes and cancer and possibly other IR-related diseases.

Placental phenotype and the insulin-like growth factors: resource allocation to fetal growth

The placenta is the main determinant of fetal growth and development in utero. It supplies all the nutrients and oxygen required for fetal growth and secretes hormones that facilitate maternal allocation of nutrients to the fetus. Furthermore, the placenta responds to nutritional and metabolic signals in the mother by altering its structural and functional phenotype, which can lead to changes in maternal resource allocation to the fetus. The molecular mechanisms by which the placenta senses and responds to environmental cues are poorly understood. This review discusses the role of the insulin-like growth factors (IGFs) in controlling placental resource allocation to fetal growth, particularly in response to adverse gestational environments. In particular, it assesses the impact of the IGFs and their signalling machinery on placental morphogenesis, substrate transport and hormone secretion, primarily in the laboratory species, although it draws on data from human and other species where relevant. It also considers the role of the IGFs as environmental signals in linking resource availability to fetal growth through changes in the morphological and functional phenotype of the placenta. As altered fetal growth is associated with increased perinatal morbidity and mortality and a greater risk of developing adult-onset diseases in later life, understanding the role of IGFs during pregnancy in regulating placental resource allocation to fetal growth is important for identifying the mechanisms underlying the developmental programming of offspring phenotype by suboptimal intrauterine growth.

Post-Transplant Diabetes Mellitus: Causes, Treatment, and Impact on Outcomes

Post-transplant diabetes mellitus (PTDM) is a frequent consequence of solid organ transplantation. PTDM has been associated with greater mortality and increased infections in different transplant groups using different diagnostic criteria. An international consensus panel recommended a consistent set of guidelines in 2003 based on American Diabetes Association glucose criteria but did not exclude the immediate post-transplant hospitalization when many patients receive large doses of corticosteroids. Greater glucose monitoring during all hospitalizations has revealed significant glucose intolerance in the majority of recipients immediately after transplant. As a result, the international consensus panel reviewed its earlier guidelines and recommended delaying screening and diagnosis of PTDM until the recipient is on stable doses of immunosuppression after discharge from initial transplant hospitalization. The group cautioned that whereas hemoglobin A1C has been adopted as a diagnostic criterion by many, it is not reliable as the sole diabetes screening method during the first year after transplant. Risk factors for PTDM include many of the immunosuppressant medications themselves as well as those for type 2 diabetes. The provider managing diabetes and associated dyslipidemia and hypertension after transplant must be careful of the greater risk for drug-drug interactions and infections with immunosuppressant medications. Treatment goals and therapies must consider the greater risk for fluctuating and reduced kidney function, which can cause hypoglycemia. Research is actively focused on strategies to prevent PTDM, but until strategies are found, it is imperative that immunosuppression regimens are chosen based on their evidence to prolong graft survival, not to avoid PTDM.

Crosstalk between the TNF and IGF pathways enhances NF-κB activation and signaling in cancer cells

BACKGROUND

The receptor for type I insulin like growth factor (IGF-IR) and NFκB signaling both play essential roles in cancer initiation and progression but relatively little is known about possible crosstalk between these pathways. We have shown that the IGF-IR could rescue lung and colon carcinoma cells from Tumor necrosis factor -α (ΤΝF-α)-induced apoptosis by activating autocrine, pro-survival IL-6/gp130/STAT3 signaling, suggesting that IGF-IR expression could alter NF-κB signaling that is required for transcriptional activation of IL-6.

OBJECTIVE

Here we sought to determine if and how IGF-IR signaling promotes TNF-α-induced NFκB activation.

DESIGN

We used lung carcinoma M-27 and colon carcinoma MC-38 cells to investigate IGF-IR-induced changes to the IKK/IκBα/NFκB pathway by a combination of qPCR, Western blotting, electrophoretic mobility shift assay, a reporter assay and gene silencing.

RESULTS

We show that in the presence of increased IGF-IR expression or activation levels, nuclear translocation of NFκB in response to TNF-α was enhanced in lung and colon carcinoma cells and this was due to accelerated phosphorylation and degradation of IκBα. This effect was AKT-dependent and mediated via mitogen-activated protein kinase kinase kinase 3(MEKK3) activation.

CONCLUSION

The results suggest that ligand-mediated activation of IGF-IR alters NF-κB signaling in cancer cells in an AKT/MEKK3-dependent manner and that temporal aspects of NF-κB activation can regulate the cytokine profile of the tumor cells and thereby, their interaction with the microenvironment.

Data Mining of Determinants of Intrauterine Growth Retardation Revisited Using Novel Algorithms Generating Semantic Maps and Prototypical Discriminating Variable Profiles

OBJECTIVES

Intra-uterine growth retardation is often of unknown origin, and is of great interest as a "Fetal Origin of Adult Disease" has been now well recognized. We built a benchmark based upon a previously analysed data set related to Intrauterine Growth Retardation with 46 subjects described by 14 variables, related with the insulin-like growth factor system and pro-inflammatory cytokines, namely interleukin-6 and tumor necrosis factor-α.

DESIGN AND METHODS

We used new algorithms for optimal information sorting based on the combination of two neural network algorithms: Auto-contractive Map and Activation and Competition System. Auto-Contractive Map spatializes the relationships among variables or records by constructing a suitable embedding space where 'closeness' among variables or records reflects accurately their associations. The Activation and Competition System algorithm instead works as a dynamic non linear associative memory on the weight matrices of other algorithms, and is able to produce a prototypical variable profile of a given target.

RESULTS

Classical statistical analysis, proved to be unable to distinguish intrauterine growth retardation from appropriate-for-gestational age (AGA) subjects due to the high non-linearity of underlying functions. Auto-contractive map succeeded in clustering and differentiating completely the conditions under study, while Activation and Competition System allowed to develop the profile of variables which discriminated the two conditions under study better than any other previous form of attempt. In particular, Activation and Competition System showed that ppropriateness for gestational age was explained by IGF-2 relative gene expression, and by IGFBP-2 and TNF-α placental contents. IUGR instead was explained by IGF-I, IGFBP-1, IGFBP-2 and IL-6 gene expression in placenta.

CONCLUSION

This further analysis provided further insight into the placental key-players of fetal growth within the insulin-like growth factor and cytokine systems. Our previous published analysis could identify only which variables were predictive of fetal growth in general, and identified only some relationships.

The IGF-1 receptor and regulation of nitric oxide bioavailability and insulin signalling in the endothelium

The insulin-like growth factor-1 receptor (IGF-1R), like the insulin receptor (IR), plays a significant role in determining bioavailability of the critical signalling molecule nitric oxide (NO) and hence, modulates endothelial cell function, particularly in response to stimulation with insulin. In particular, the ability of the IGF-1R to form hybrid receptors with the IR appears to be highly significant in determining the sensitivity of the endothelial cell to insulin. This review will examine the structure of the IGF-1R and how this, with particular reference to the ability of the IGF-1R and the IR to form hybrid receptors, may have an effect both on endothelial cell function and the development of cardiovascular disease.

Improvement of insulin sensitivity promotes extravillous trophoblast cell migration stimulated by insulin-like growth factor-I

Insulin-like growth factor-I (IGF-I) has been shown to stimulate extravillous trophoblast (EVT) cell migration and invasion, and to play a crucial role in placental function, thereby, influencing placental development and fetal growth. Insufficient invasion of EVT cells into the uterine endometrium leads to pregnancy-related complications, including spontaneous abortion, fetal growth restriction (FGR), and pregnancy-induced hypertension (PIH). Insulin-resistant conditions such as polycystic ovary syndrome (PCOS) and gestational diabetes mellitus (GDM) have also been associated with abortion and PIH. However, the effects of IGF-I on EVT cells under insulin-resistant conditions have not been elucidated yet. The current study was undertaken to analyze the effects of IGF-I under insulin-resistant conditions and to determine whether improvement in insulin sensitivity alters IGF signaling and cell migration in the EVT. Incubation with pioglitazone, an insulin sensitizer, increased peroxisome proliferator-activated receptor-γ (PPARγ) expression after 48 h. A 48-h pre-incubation with insulin reduced the phosphorylation and concentration of the insulin receptors, which were increased by insulin treatment. Long-term exposure to insulin reduced phosphorylation of the IGF-I receptor, insulin receptor substrate-1 (IRS-1), and Akt, and also reduced EVT cell migration. However, when the cells were incubated with pioglitazone in addition to insulin for 48 h, the phosphorylation of these proteins was restored. This combination partially reversed the inhibitory effect of insulin on EVT cell migration. These results suggest that abnormalities in pregnancy that are induced by loss of insulin sensitivity can be treated by improving insulin sensitivity.

Effects of increased fetuin-A in human trophoblast cells and associated pregnancy outcomes

OBJECTIVE

The purpose of this study was to determine whether fetuin-A affects trophoblast viability and invasion, whether growth factors that bind receptors that activate tyrosine kinase are impaired by fetuin-A, and whether elevated maternal serum fetuin-A levels are associated with adverse pregnancy outcomes.

STUDY DESIGN

We studied viability and invasion in first-trimester extravillous trophoblast cells that were exposed to fetuin-A, insulin-like growth factor, and placental growth factor. Insulin receptor substrates expression was assessed. We compared serum fetuin-A levels in 111 preeclampsia cases and 95 controls.

RESULTS

Fetuin-A reduced extravillous trophoblast cell viability and invasion in the presence or absence of growth factors. Fetuin-A reduced insulin receptor substrate-1 and tyrosine phosphorylated insulin receptor substrate-1 expression in extravillous trophoblast cells that had been treated with insulin-like growth factor. Elevated serum fetuin-A levels were more prevalent in preeclampsia cases than control subjects, even after we controlled for diabetes mellitus, hypertension, and obesity.

CONCLUSION

Fetuin-A may decrease trophoblast viability and invasion caused by the inhibition of receptor tyrosine kinase activity. Elevated serum levels of fetuin-A may be associated with preeclampsia.

Placental malaria-associated inflammation disturbs the insulin-like growth factor axis of fetal growth regulation

BACKGROUND

The pathogenetic mechanisms of fetal growth restriction associated with placental malaria are largely unknown. We sought to determine whether placental malaria and related inflammation were associated with disturbances in the insulin-like growth factor (IGF) axis, a major regulator of fetal growth.

METHOD

We measured IGF-1 and IGF-2 concentrations in plasma from 88 mother-neonate pairs at delivery and IGF binding proteins 1 and 3 (IGFBP-1 and IGFBP-3, respectively) in cord plasma from a cohort of Papua New Guinean women with and without placental malaria. Messenger RNA levels of IGF-1, IGF-2, and the IGF receptors were measured in matched placental biopsy specimens.

RESULTS

Compared with those for uninfected pregnancies, IGF-1 levels were reduced by 28% in plasma samples from women with placental Plasmodium falciparum infection and associated inflammation (P = .007) and by 25% in their neonates (P = .002). Levels of fetal IGFBP-1 were elevated in placental malaria with and without inflammation (P = .08 and P = .006, respectively) compared with uninfected controls. IGF-2 and IGFBP-3 plasma concentrations and placental IGF ligand and receptor messenger RNA transcript levels were similar across groups.

CONCLUSION

Placental malaria-associated inflammation disturbs maternal and fetal levels of IGFs, which regulate fetal growth. This may be one mechanism by which placental malaria leads to fetal growth restriction.