Villous histomorphometry and placental bed biopsy investigation in Type I diabetic pregnancies

Fetoplacental oxygen homeostasis in pregnancies with maternal diabetes mellitus and obesity

Despite improvements in clinical management, pregnancies complicated by pre-existing diabetes mellitus, gestational diabetes mellitus or obesity carry substantial risks for parent and offspring. Some of the endocrine and metabolic changes in parent and fetus in diabetes mellitus and obesity lead to fetal oxygen deficit, mostly due to insulin-induced accelerated fetal metabolism. The human fetus deals with reduced oxygenation through a wide range of adaptive responses that act at various levels in the placenta as well as the fetus. These responses ensure adequate oxygen delivery to the fetus, increase the oxygen transport capacity of fetal blood and redistribute oxygen-rich blood to vital organs such as the brain and heart. The liver has a central role in adapting to reduced oxygenation by increasing its oxygen extraction and stimulating erythropoietin synthesis to increase haematocrit. The type of adaptive response depends on the onset and duration of hypoxia and the severity of the metabolic disturbance. In pregnancies characterized by diabetes mellitus or obesity, these adaptive systems come under additional strain owing to the increased maternal supply of glucose and resultant fetal hyperinsulinaemia, both of which stimulate oxidative metabolism. In the rare situation that the adaptive responses are overwhelmed, stillbirth can ensue.

Clinicopathological study and immunohistochemical analysis of expression of annexin A5 and apelin in human placentae of gestational diabetes mellitus

BACKGROUND AND AIMS

Gestational diabetes mellitus (GDM) is one of the commonest medical complications of pregnancy. Annexin A5 (ANXA5) is a protein, found in apical surfaces of syncytiotrophoblasts, which prevents fetal and placental vascular thrombosis in GDM. Apelin is a bioactive peptide which has been linked to GDM. The aim of the present study was to correlate macroscopic as well as microscopic changes and immunohistochemical expression of ANXA5 and apelin in placentae of GDM with maternal and neonatal clinical features and also to compare the results with those in matched controls.

METHODS

This prospective observational study was undertaken for a period of one year from April 2020 to March 2021. It comprised of 42 patients of GDM. Gross features, microscopic features and intensity and grade of expression of ANXA5 and Apelin were analyzed in placentae of GDM.

RESULTS

Morphological changes detected in GDM placentae included increased immature villi (16 cases, 38%), increased syncytial knots (36, 86%), perivillous fibrin deposition (20, 48%), fibrosis of villous stroma (20, 48%), presence of nucleated red blood cells (12, 28.5%) and hypervascularity (34, 81%). The extent of histopathological changes noted in GDM placentae was significantly higher than that in matched controls. GDM placentae showed significantly reduced expression of ANXA5 and Apelin in terms of grade and intensity when compared with matched controls. Reduced expression (mild intensity) of ANXA5 was noted in 22 GDM cases (52.3%) whereas apelin expression was of weak intensity in 26 (61.9%) cases. Among GDM patients, statistically significant association was noted between ANXA5 intensity and neonatal resuscitation, apelin grade and preterm birth as well as low birth weight and apelin intensity and requirement of treatment in sick neonatal care unit.

CONCLUSION

The placental expression of the proteins, ANXA5 and Apelin, is altered in GDM though their exact pathogenetic mechanisms are yet to be understood. They can be targets for development of prophylactic and therapeutic agents in future.

Abnormal umbilical cord insertions in singleton deliveries: placental histology and neonatal outcomes

AIMS

This study aimed to identify any microscopic features associated with abnormal (membranous/velamentous or marginal) placental cord insertions and to analyse their adverse neonatal outcomes.

METHODS

We retrospectively analysed the records-including pathological findings, clinical information and pregnancy outcomes-for 1060 singleton pregnancies, involving newborn delivered after 24 weeks of gestation.

RESULTS

Marginal cord insertions were identified in 26.60% of cases and membranous cord insertions in 2.64%. Subchorionic vessel thrombus was more prevalent in marginal or membranous insertions (0.97%) than in normal cord insertions (0.27%) (p=0.129). Intervillous thrombi (13.73% vs 8.41%, p<0.05) and chorioamnionitis (8.53% vs 5.48%, p=0.089) were more prevalent in normal cord insertions. Premature rupture of membranes was significantly more commonly associated with abnormal (marginal 15.25% and membranous 17.86%) than with normal (9.87%) insertions (p<0.05). Pre-eclampsia was more common in the group with membranous cord insertions (7.14%) than in the other groups (marginal 0.35%; normal 0.80%) (p<0.05). Marginal and membranous placental cord insertions were associated with earlier gestational age at delivery and smaller fetuses than in the group with normal insertions. Intrauterine fetal demise, cardiac malformations and pregestational diabetes were also more common among cases of abnormal cord insertions.

CONCLUSIONS

Subchorionic vessel thrombus and adverse pregnancy-related outcomes were more prevalent in cases of marginal/membranous cord insertion than for normal insertions.

Spiral Arteries in Second Trimester of Pregnancy: When Is It Possible to Define Expected Physiological Remodeling as Abnormal?

After undergoing remodeling, uterine spiral arteries turn into wide, flexible tubes, with low resistance. If remodeling does not occur, spontaneous abortions, intrauterine growth restriction, and pregnancy-related hypertensive disorders can ensue. Arterial transformation begins at a very early gestational stage; however, second quarter pregnancy histopathological samples have yet to pinpoint the exact moment when abnormal remodeling transpires. We examined 100 samples, taken from consecutive abortions at 12-23 gestational weeks. Following Pijnenborg and Smith guidelines, blinded pathologists analyzed clinical data on remodeling stages. Lab results showed that arterial remodeling is not synchronic in all vessels; a single sample can include various remodeling stages; neither is remodeling homogenous in a single vessel: change may be occurring in one part of the vessel, but not in another. To our knowledge, no one has published this finding. In the examined age group, Smith stage IV predominates; around week 14, substantial muscle and endothelium loss takes place. After week 17, endovascular or fibrin trophoblast does not usually occur. Although scant consensus exists on what defines preeclampsia etiology, it is clear that it involves abnormal remodeling in decidua vessels. Improved understanding requires further knowledge on both the physiological and pathological aspects of the remodeling process. We observed that muscle and endothelial tissues disappear from weeks 14-17, after which time reendothelization predominates. We list the expected proportion of spiral artery changes for each gestational age which, to date, has not been available.

Fetal cardiovascular hemodynamics in type 1 diabetic pregnancies at near-term gestation

INTRODUCTION

Poor glycemic control in maternal type 1 diabetes mellitus during pregnancy can affect fetal cardiac and placental function. However, studies concerning fetal central hemodynamics have revealed conflicting results. We hypothesized that in pregnancies complicated by maternal type 1 diabetes, fetal cardiovascular and placental hemodynamics are comparable to the control fetuses at near-term gestation. In addition, we investigated the relation between newborn serum biomarkers of cardiac function and fetal cardiovascular and placental hemodynamics. Furthermore, we studied whether maternal diabetes is associated with placental inflammation.

MATERIAL AND METHODS

In this prospective case-control study, fetal central and peripheral hemodynamics were assessed by ultrasonography in 33 women with type 1 diabetes and in 67 controls with singleton pregnancies between 34⁺² and 40⁺² gestational weeks. Newborn umbilical cord serum was collected to analyze cardiac natriuretic peptides (atrial and B-type natriuretic peptides) and troponin T concentrations. Placental tissue samples were obtained for cytokine analyses.

RESULTS

Fetal ventricular wall thicknesses were greater and weight-adjusted stroke volumes and cardiac outputs were lower in the type 1 diabetes group than in the control group. Pulsatility in the aortic isthmus and inferior vena cava blood flow velocity waveforms was greater in the type 1 diabetes group fetuses than in the controls. A positive correlation was found between branch pulmonary artery and aortic isthmus pulsatility index values. Umbilical artery pulsatility indices were comparable between the groups. Umbilical cord serum natriuretic peptide and troponin T concentrations were elevated in the type 1 diabetes fetuses. These cardiac biomarkers correlated significantly with cardiovascular hemodynamics. Placental cytokine levels were not different between the groups.

CONCLUSIONS

In maternal type 1 diabetes pregnancies, fetal cardiovascular hemodynamics is impaired. Maternal type 1 diabetes does not seem to alter placental vascular impedance or induce placental inflammation.

[Comparative morphofunctional analysis of the state of fetoplacental complex in diabetes mellitus (literature review)]

This article reviews the literature on placental morphofunctional changes in placenta of patients with type 1 and type 2 diabetes mellitus and gestational diabetes mellitus. The detailed analysis of features of pathogenesis of various abnormalities of the fetoplacental complex depending on the type of diabetes, its influence on the formation of the placental vascular bed. The analysis of mechanisms of development of placenta formation disorders, pathologies of placental vascular bed, the role of hyperglycemia and hyperinsulinemia in villous maturation, placental weight gain, perinatal outcomes. The discussed anomalies have a significant impact on the fetoplacental complex, acting as epigenetic factors, forming the environment for the fetus, which may later affect the health of the unborn child. They lead to adverse perinatal outcomes, including high infant morbidity and mortality. Literature search was performed in Russian (eLibrary, CyberLeninka.ru) and international (PubMed, Cochrane Library) databases in Russian and English languages. The free access to the full text of the articles was in priority. The selection of sources was prioritized for the period from 2016 to 2020. However, due to the lack of knowledge of the chosen topic, the selection of sources was dated from 2001.

First trimester placental volume and vascular indices in pregestational diabetic compared to nondiabetic pregnant women

AIM

Comparing placental volume (PV) and vascular indices in pregestational diabetic and nondiabetic pregnant women at 11 and 13 weeks gestation.

METHODS

A case-control study conducted at Ain Shams University Maternity Hospital in collaboration with Feto-maternal Unit for Ultrasound Assessment, Ain Shams University Maternity Hospital, Egypt. Ninety-two pregnant women divided into two groups: Group A included 46 women with pregestational diabetes mellitus and group B included 46 nondiabetic pregnant women as control. All participants had PV, vascularization index (VI), flow index (FI) and vascularization flow index (VFI) calculated using three-dimensional (3D) ultrasonography and 3D power Doppler at 11 and 13 weeks of pregnancy.

RESULTS

At 11 weeks, the mean VI, FI and VFI in diabetic group (17.70 ± 12.62, 40.72 ± 11.03 and 7.77 ± 6.37, respectively) were insignificantly higher than in nondiabetic group (12.14 ± 12.62, 34.59 ± 9.66 and 6.52 ± 14.20, respectively) while mean PV in diabetic group (26.90 ± 14.74) was insignificantly lower than in nondiabetic group (27.53 ± 17.46). Also at 13 weeks, the results were not different as the mean VI, FI and VFI in diabetic group (16.51 ± 9.81, 42.52 ± 7.47 and 8.12 ± 7.55, respectively) were insignificantly higher than in nondiabetic group (16.37 ± 14.17, 40.29 ± 17.52 and 7.08 ± 4.35, respectively), and mean PV in diabetic group (52.04 ± 17.95) was insignificantly lower than in nondiabetic group (54.46 ± 17.85). There was strong positive correlation between HbA1C level and VFI measured at 13 weeks gestation.

CONCLUSIONS

Placental indices in early pregnancy do not seem to be useful markers to anticipate placental pathology in pregestational diabetes, however there might be a role for HbA1C level measurement to anticipate such complications.

Histopathological study with immunohistochemical expression of vascular endothelial growth factor in placentas of hyperglycemic and diabetic women

AIMS AND OBJECTIVES

Spectrum of hyperglycemia in pregnancy includes gestational diabetes mellitus (GDM), mild hyperglycemia, and overt diabetes. Many authors have worked on morphological changes of the placenta in diabetes, but few studies have correlated histopathological changes with vascular endothelial growth factor (VEGF) immunoexpression. The aim of this study was to detect different histopathological changes in various groups of diabetic placentas and to correlate with VEGF immunoexpression.

MATERIALS AND METHODS

Pregnant women were screened for diabetes. They were subsequently divided into normoglycemic (12 cases), GDM (33 cases), mild hyperglycemic (13 cases), and overt diabetes (18 cases). Placentas collected were subjected to histopathological examination. VEGF expressions were studied by immunohistochemistry.

RESULTS

Overt diabetic placenta displayed villous immaturity (44.4%), villous edema (38.9%), chorangiosis (61.1%), fibrinoid substance deposition (38.9%), and Hofbauer cell hyperplasia in 44.4% cases. GDM placentas displayed villous immaturity (45.5%), villous edema (45.5%), chorangiosis (42.4%), and fibrinoid substance deposition in 75.6% cases. Mild hyperglycemic placentas displayed villous immaturity (38.5%), chorangiosis (61.5%), and fibrinoid substance deposition in 61.5% cases. VEGF immunoexpression in GDM placentas was absent in all placental components except syncytiotrophoblast. VEGF expression in overt diabetic placentas was increased in syncytiotrophoblast and capillary endothelium compared to normoglycemic placentas. Mild hyperglycemic placentas expressed similar VEGF expression in all components when compared to normoglycemic controls. However, it displayed weak expression in vessel endothelium.

CONCLUSION

Histopathological changes in diabetic placentas might be a consequence of altered or abnormal VEGF expression in diabetic placentas. Pathogenesis and VEGF expression in GDM placentas are significantly different from overt diabetic placentas.

Placental structure in gestational diabetes mellitus

The placenta is a transitory organ, located between the mother and the foetus, which supports intrauterine life. This organ has nutritional, endocrine and immunologic functions to support foetal development. Several factors are related to the correct functioning of the placenta including foetal and maternal blood flow, appropriate nutrients, expression and function of receptors and transporters, and the morphology of the placenta itself. Placental morphology is crucial for understanding the pathophysiology of the organ as represents the physical structure where nutrient exchange occurs. In pathologies of pregnancy such as diabetes mellitus in humans and animal models, several changes in the placental morphology occur, related mainly with placental size, hypervascularization, higher branching capillaries of the villi and increased glycogen deposits among others. Gestational diabetes mellitus is associated with modifications in the structure of the human placenta including changes in the surface area and volume, as well as histological changes including an increased volume of intervillous space and terminal villi, syncytiotrophoblast number, fibrinoid areas, and glycogen deposits. These modifications may result in functional changes in this organ thus limiting the wellbeing of the developing foetus. This review gives an overview of recurrent morphological changes at macroscopic and histological levels seen in the placenta from gestational diabetes in humans and animal models. This article is part of a Special Issue entitled: Membrane Transporters and Receptors in Pregnancy Metabolic Complications edited by Luis Sobrevia.

Modulation of trophoblast function by concurrent hyperglycemia and antiphospholipid antibodies is in part TLR4-dependent

PROBLEM

While diabetes and APS are individually associated with increased risk of poor perinatal outcomes, in particular preeclampsia, recent studies have demonstrated an association between concurrent aPL and diabetes leading to an increased risk of pregnancy morbidity. Hyperglycemia and aPL have independently been shown to alter human trophoblast function by inducing a pro-inflammatory, anti-angiogenic, and antimigratory response. However, little is known about the effects of concurrent hyperglycemia and aPL on trophoblast function.

METHOD OF STUDY

A human first-trimester extravillous trophoblast cell line was exposed to glucose at 5 mmol/L (normoglycemia) or 25 mmol/L (hyperglycemia), all in the presence or absence of low-dose aPL or control IgG. For some experiments, the TLR4 antagonist, LPS-RS, was included. Cell culture supernatants were measured for inflammatory IL-1β and IL-8, and angiogenic PlGF, sFlt-1, and sEndoglin by ELISA. Inflammasome-associated uric acid was measured using a bioassay; caspase-1 was measured using an activity assay. Trophoblast migration was quantified using a two-chamber colorimetric assay.

RESULTS

Compared to excess glucose alone, combination excess glucose and low-dose aPL (a) further augmented trophoblast inflammatory IL-1β, inflammasome-associated uric acid and caspase-1, and pro-angiogenic PlGF; (b) dampened trophoblast inflammatory IL-8, anti-angiogenic sEndoglin, and sFlt-1; and (c) further reduced trophoblast migration.

CONCLUSION

Our findings indicate that while concurrent aPL and hyperglycemia are overall detrimental to trophoblast function, the presence of two simultaneous insults triggers some protective effects.

Peripartum fetal distress in diabetic women: a retrospective case-cohort study

Background

Major concerns of pregnancies complicated by diabetes mellitus are an increased risk of adverse perinatal outcome. The objective of this study was to analyse the rate of fetal distress during labor in women with type 1, type 2 and gestational diabetes compared to control women.

Methods

A retrospective case-cohort study was conducted at the VU University Medical Center, Amsterdam; a tertiary care hospital. 117 women with type 1 diabetes, 59 women with type 2 diabetes, 303 women with gestational diabetes and 15,260 control women were included, who delivered between March 2004 and February 2014. Linear and logistic regression analyses were used to compare maternal and pregnancy characteristics. Risk of fetal distress and perinatal asphyxia was assessed by multiple regression analyses, adjusted for confounding factors as age, smoking, parity, previous cesarean section, hypertensive disorder, pre-eclampsia, prematurity, induction of labor and macrosomia. Main outcome measure was fetal distress, defined either as clinical indication for instrumental or cesarean delivery; or low umbilical artery pH (UA pH), or admission to neonatal unit (NU).

Results

The indication for instrumental or cesarean delivery in women with type 1 and type 2 diabetes mellitus was more frequently based on fetal distress as compared to controls (adjusted OR 2.76 CI 1.74–4.40 and adjusted OR 2.31 CI 1.19–4.51, respectively). In comparison with the control group, infants of women with type 1 diabetes had an increased risk of UA pH < 7.20 (adjusted OR 1.88 CI 1.23–2.87) or UA pH < 7.10 (adjusted OR 3.35 CI 1.79–6.27). Also, infants of women with type 1 diabetes were at increased risk for admission to NU as compared to infants of control women (OR 8.07 CI 4.75–13.70).

Conclusions

Women with type 1 and type 2 diabetes are at increased risk of fetal distress during labor as compared to controls.

Prokineticin 1 is up-regulated by insulin in decidualizing human endometrial stromal cells

Prokineticin 1 (PROK1), a hypoxia‐regulated angiogenic factor, has emerged as a crucial regulator of embryo implantation and placentation. Dysregulation of PROK1 has been linked to recurrent pregnancy loss, pre‐eclampsia, foetal growth restriction and preterm birth. These pregnancy complications are common in women with obesity and polycystic ovary syndrome, i.e. conditions associated with insulin resistance and compensatory hyperinsulinaemia. We investigated the effect of insulin on PROK1 expression during in vitro decidualization. Endometrial stromal cells were isolated from six healthy, regularly menstruating women and decidualized in vitro. Insulin induced a significant dose‐dependent up‐regulation of PROK1 on both mRNA and protein level in decidualizing endometrial stromal cells. This up‐regulation was mediated by hypoxia‐inducible factor 1‐alpha (HIF1α) via the phosphatidylinositol 3‐kinase (PI3K) pathway. Furthermore, we demonstrated that PROK1 did not affect the viability, but significantly inhibited the migration of endometrial stromal cells and the migratory and invasive capacity of trophoblast cell lines. This in vitro study provides new insights into the regulation of PROK1 by insulin in human decidualizing endometrial stromal cells, the action of PROK1 on migration of endometrial stromal cells, as well as migration and invasion of trophoblasts. We speculate that hyperinsulinaemia may be involved in the mechanisms by which PROK1 is linked to placenta‐related pregnancy complications.

Decidual arteriolopathy with or without associated hypertension modifies the underlying histomorphology in placentas from diabetic mothers

AIM

The aim of this study was to retrospectively document the impact of hypertensive conditions in pregnancy and decidual arteriolopathy on the patterns of placental injury in maternal diabetes mellitus (MDM).

METHODS

Among all 5248 > 20 weeks' placentas, the frequencies of 19 selected clinical and 24 placental phenotypes were compared between 287 MDM placentas and 4961 remaining placentas (control group [CG]) before and after further exclusion of 85 and 611 patients with hypertensive conditions (gestational hypertension, pre-eclampsia, chronic hypertension).

RESULTS

Cesarean section rate, heavy placentas, decidual arteriolopathy, microscopic chorionic pseudocysts, and chorangiosis were more common in MDM than in the CG both before and after exclusion of hypertensive conditions. The frequencies of preuterine patterns of chronic hypoxic placental injury and plasma cell deciduitis became statistically significant only after exclusion of hypertensive conditions.

CONCLUSION

Hypertensive conditions of pregnancy may obscure the underlying preuterine placental hypoxic pattern in MDM placentas. Even in normotensive patients, decidual arteriolopathy, and shallow placental implantation significantly impact placental histomorphology in MDM.

A clinical study which relates to a theoretical simulation of the glucose transport in the human placenta under various diabetic conditions

AIMS

To characterize placental glucose delivery under normoglycemic conditions, gestational and pre-gestational diabetes and to relate the clinical data to theoretical predictions.

METHODS

Data from 125 pregnancies: 50 normal gestations and 75 ones with various types of diabetes were collected. In parallel, we formulated a theoretical model for the transport of glucose under various diabetic conditions. Measured glucose blood levels were fed into the theoretical model that predicts glucose supply to the fetus and the results were confronted with measured fetal weights.

RESULTS

Measured fetal weight and computed glucose delivery in gestational diabetic parturients resemble the situation in normal pregnancies. However, pre-gestational diabetes has a major effect as it involves heavier fetuses and enhanced computed glucose fluxes via placental membranes.

CONCLUSIONS

Fetal weight (increased in pre-gestational and unaltered in gestational diabetes) correlates with the predicted rate of glucose delivery through the placenta.

Shear wave elastography of the placenta in patients with gestational diabetes mellitus

To evaluate placental elasticty in women with gestational diabetes mellitus (GDM) and non-diabetic controls. Thirty-three pregnant women with GDM according to the current criteria of the American Diabetes Association and 43 healthy pregnant women who were admitted to the antenatal clinic were recruited for this case-control study. Elasticity values of both the peripheral and the central parts of the placentas of the patients in both groups were determined by shear wave elastography (SWE) imaging. Mean elasticity values of both the central and the peripheral part of the placentas were significantly higher in GDM pregnancies (p < 0.001). No difference was observed in the mean elasticity values of the central and the peripheral part of the placentas in two groups (p > 0.05). SWE imaging technology might provide a quantitative assessment of the morphological pathologies of placentas in pregnant women with GDM.

Vascular endothelial growth factor and its receptors in the placenta of women with type 1 diabetes mellitus

We performed a morphological study of placentas from women with type 1 diabetes mellitus receiving insulin therapy (insulin pump). Expression of vascular endothelial growth factor (VEGF) and its receptors (VEGFR-1, VEGFR-2, VEGFR-3) was demonstrated by immunohistochemical methods. Processes of branched angiogenesis predominated in the placentas from women with type 1 diabetes mellitus. Immunohistochemical study revealed more intensive reaction of VEGF and its receptors in syncytiotrophoblast and capillary endothelium of terminal villi.

Maternal Body Weight and Gestational Diabetes Differentially Influence Placental and Pregnancy Outcomes

CONTEXT

Maternal obesity and gestational diabetes mellitus (GDM) can both contribute to adverse neonatal outcomes. The extent to which this may be mediated by differences in placental metabolism and nutrient transport remains to be determined.

OBJECTIVE

Our objective was to examine whether raised maternal body mass index (BMI) and/or GDM contributed to a resetting of the expression of genes within the placenta that are involved in energy sensing, oxidative stress, inflammation, and metabolic pathways.

METHODS

Pregnant women from Spain were recruited as part of the "Study of Maternal Nutrition and Genetics on the Foetal Adiposity Programming" survey at the first antenatal visit (12-20 weeks of gestation) and stratified according to prepregnancy BMI and the incidence of GDM. At delivery, placenta and cord blood were sampled and newborn anthropometry measured.

RESULTS

Obese women with GDM had higher estimated fetal weight at 34 gestational weeks and a greater risk of preterm deliveries and cesarean section. Birth weight was unaffected by BMI or GDM; however, women who were obese with normal glucose tolerance had increased placental weight and higher plasma glucose and leptin at term. Gene expression for markers of placental energy sensing and oxidative stress, were primarily affected by maternal obesity as mTOR was reduced, whereas SIRT-1 and UCP2 were both upregulated. In placenta from obese women with GDM, gene expression for AMPK was also reduced, whereas the downstream regulator of mTOR, p70S6KB1 was raised.

CONCLUSIONS

Placental gene expression is sensitive to both maternal obesity and GDM which both impact on energy sensing and could modulate the effect of either raised maternal BMI or GDM on birth weight.

The impact of insulin treatment on the expression of vascular endothelial cadherin and Beta-catenin in human fetoplacental vessels

Vascular endothelial cadherin and β-catenin play a key role in establishment and maintenance of the endothelial monolayer integrity, regulation of vascular barrier function, and initiation of angiogenesis. The cadherin-catenin complex has been shown to be reduced in type 1 diabetic placenta, but the exact relationship between histopathologic findings and clinical data is not known. Immunohistochemistry of placental tissue from type 1, type 2, and gestational diabetes showed that diabetes per se might be compatible with normal levels of vascular endothelial (VE)-cadherin and β-catenin in fetoplacental vessels as long as the patient has not been treated with insulin. Immunoreactivity of VE-cadherin did correlate poorly with maternal glycemic control, as was investigated in this study, by birth weight, body mass index, and hemoglobin A1c (HbA1c). There was no correlation found between the immunoreactivity of β-catenin and birth weight, body mass index, or HbA1c. However our data did show a strong correlation between immunoreactivity and whether or not the patient had been treated with insulin. Patients diagnosed with gestational diabetes who had not been treated with insulin had similar levels of VE-cadherin and β-catenin to the control group, thus indicating that diabetes per se must not necessarily lead to a reduction. Our study suggests that therapeutic intervention using insulin in pregnancies complicated by diabetes might have potentially harmful effects on placental morphology. Future studies should further investigate these findings.

Impaired trophoblast invasion and increased numbers of immune cells at day 18 of pregnancy in the mesometrial triangle of type 1 diabetic rats

INTRODUCTION

Type 1 diabetes (T1D) is associated with adverse pregnancy outcome, usually attributed to hyperglycemia. Recently, we showed that pregnancy outcome in normoglycemic T1D rats was characterized by decreased fetal and placental weight, suggesting impaired placental development. In the present study, we tested the hypothesis that trophoblast invasion and spiral artery (SA) remodeling is impaired in T1D rats ant that this is associated with aberrant local presence of NK cells and macrophages in the mesometrial triangle (MT).

METHODS

Placentae with MT from pregnant biobreeding diabetes-prone (BBDP; T1D model) rats, control biobreeding diabetes-resistant (BBDR) and Wistar-rats were dissected at day 18 of gestation and stained for trophoblast invasion, SA remodeling, uNK cells and macrophages.

RESULTS

Interstitial trophoblast invasion and SA remodeling was impaired in BBDP-rats vs. control rats, coinciding with increased presence of NK cells and an increased iNOS+/CD206+ ratio of macrophages.

DISCUSSION

Decreased fetal and placental weight in BBDP-rats was associated with diminished interstitial trophoblast invasion and less optimal SA remodeling, increased numbers of NK cells and increased iNOS+/CD206+ macrophage ratio in the MT of BBDP-rats.

CONCLUSIONS

The impaired trophoblast invasion and SA remodeling may be due to an aberrant local immune-response and may result in damage to the fetal placenta and insufficient supply of nutrients towards the fetus with eventually decreased fetal weight as a consequence.

A systematic review of placental pathology in maternal diabetes mellitus

INTRODUCTION

During a pregnancy complicated by diabetes, the human placenta undergoes a number of functional and structural pathologic changes, such as increased placental weight and increased incidence of placental lesions including villous maturational defects and fibrinoid necrosis. The pathologic findings reported have differed among studies, potentially reflecting differences in type of diabetes, study methodology, or glycemic control of study participants. Alternatively, these discrepancies may represent different biologic adaptations to distinct metabolic diseases.

METHODS

We conducted a comprehensive review of English language citations in Pubmed and Embase using the keywords "diabetes", "placenta", AND "pathology". Abstracts were reviewed for relevance then full-text articles were reviewed in order to extract a comprehensive summary of current pathological findings associated with pregestational and gestational diabetes mellitus, as well as an understanding of the impact of glycemic control on placental pathology.

RESULTS

Placental abnormalities most consistently associated with maternal diabetes are an increased incidence of villous immaturity, increased measures of angiogenesis, and increased placental weight.

CONCLUSIONS

The literature suggests that, despite similarities in placental abnormalities, differences in placental pathology may reflect differences in pathophysiology among different types of diabetes. Consequently, standardization of terminology used to define placental lesions is warranted. Moreover, further research is needed to investigate the impact of pathophysiology, glycemic control and clinical factors, such as infant sex, weight and race, on placental structure and function.

Are there any relationships between umbilical artery Pulsatility Index and macrosomia in fetuses of type I diabetic mothers?

OBJECTIVE

To establish whether there are relationships between umbilical artery Pulsatility Index (PI) and fetal macrosomia in pregnancies complicated by type I diabetes.

METHODS

In a retrospective observational study, 102 singleton pregnant women with type I diabetes were considered. Umbilical artery PI was measured by Doppler ultrasonography within one week from delivery and related to neonatal weight. Pregnancies were grouped according to birtweight in macrosomic group (≥4000 g) and normal growth group (<4000 g). Relationships between umbilical artery PI and birth weight and birth weight centile were tested by Pearson's correlation analysis. Further umbilical artery PI values were compared between macrosomic and normally grown fetuses.

RESULTS

Birth weight was ≥4000 g in 24 pregnancies (23.5%). A significant relationship was found between umbilical artery PI and neonatal weight (r = 0.512; p < 0.01) and neonatal weight centile (r = 0.400; p < 0.01). Umbilical artery PI were significantly lower (t = -6.013; p < 0.001) in the macrosomic group (0.78; 95% confidence interval (CI) 0.73-0.84) than in the normal growth group (1.00; 95% CI 0.97-1.04).

CONCLUSIONS

In pregnancies complicated by type I diabetes there is a significant relationship between umbilical artery PI value before delivery and absolute birth weight and birth weight centile. Macrosomic fetuses show a significant reduction in umbilical artery PI when compared with diabetic pregnancies without fetal overgrowth.

Glucose, insulin, and oxygen interplay in placental hypervascularisation in diabetes mellitus

The placental vasculature rapidly expands during the course of pregnancy in order to sustain the growing needs of the fetus. Angiogenesis and vascular growth are stimulated and regulated by a variety of growth factors expressed in the placenta or present in the fetal circulation. Like in tumors, hypoxia is a major regulator of angiogenesis because of its ability to stimulate expression of various proangiogenic factors. Chronic fetal hypoxia is often found in pregnancies complicated by maternal diabetes as a result of fetal hyperglycaemia and hyperinsulinemia. Both are associated with altered levels of hormones, growth factors, and proinflammatory cytokines, which may act in a proangiogenic manner and, hence, affect placental angiogenesis and vascular development. Indeed, the placenta in diabetes is characterized by hypervascularisation, demonstrating high placental plasticity in response to diabetic metabolic derangements. This review describes the major regulators of placental angiogenesis and how the diabetic environment in utero alters their expression. In the light of hypervascularized diabetic placenta, the focus was placed on proangiogenic factors.

Comparing the expression patterns of placental magnesium/phosphorus-transporting channels between healthy and preeclamptic pregnancies

Preeclampsia is a pregnancy-specific disorder characterized by de novo development of concurrent hypertension, proteinuria, and placental oxidative stress. During the last trimester of gestation, maternal-to-fetal transport of minerals is dramatically increased and becomes tightly mediated by ion channels that are highly permeable to various divalent cations, such as Ca(2+) , Mg(2+) , and Zn(2+) . The regulation of magnesium/inorganic phosphorus ion-channel transport in the placenta, however, is not incompletely understood. In the present study, we examined the regulation of magnesium/inorganic phosphorus channels (MPCs) in the placenta of pregnant women suffering from preeclampsia as well as in primary human placental cells subjected to oxidative stress. The expression of MPC genes (TRPM6, TRPM7, PiT-1, and PiT-2) was down-regulated in preeclamptic placenta tissues during preterm labor, and generally remained lower at term labor-although TRPM7 expression in the central placenta or PiT-2 expression in whole placenta was unchanged or up-regulated. Consistent with this association, expression of MPC genes in the primary placental cells was reduced under hypoxic conditions. TRPM6, TRPM7, and PiT-1 channels were predominantly detected in the syncytiotrophoblast layers of the placenta. In contrast, PiT-2 was abundant in the placental intravillous connective tissues. Taken together, our findings indicated that placental MPC expression is down-regulated in cases of preeclampsia and under hypoxia. This relationship may contribute to a better understanding of the interrelationship between magnesium/inorganic phosphorus imbalances and preeclampsia development during preterm or term labor.

A theoretical model of glucose transport suggests symmetric GLUT1 characteristics at placental membranes

The process of glucose transport via the placenta is not fully deciphered. Here, we apply a theoretical model to compute glucose fluxes via the terminal villi of the human placenta for various sets of parameter values and conclude on characteristics of transport across the two bordering membranes. Based on available measured data, the spatial geometry of the terminal villi is being simulated. Within this region, glucose concentrations and fluxes are computed by a numerical scheme that solves the diffusion equation with boundary conditions that account for transporter mediated diffusion at the membranes. Feasible parameter values (ones that induce physiological glucose fluxes) are determined for four optional symmetry characteristics of the membranes. Confronting computed results with clinical knowledge reveals the most plausible scenario-symmetric activity of the transporter at the microvillous membrane. Thus, sensitivity analysis of the computed results enables deduction about micro-scale mechanisms at the bordering membranes based on macro-scale knowledge.

Placental histomorphometry in gestational diabetes mellitus: the relationship between subsequent type 2 diabetes mellitus and race/ethnicity

OBJECTIVES

We examined placental histomorphometry in gestational diabetes mellitus (GDM) for factors associated with race/ethnicity and subsequent type 2 diabetes mellitus (T2DM).

METHODS

We identified 124 placentas from singleton, full-term live births whose mothers had clinically defined GDM and self-reported race/ethnicity. Clinical and placental diagnoses were abstracted from medical records.

RESULTS

Forty-eight white and 76 nonwhite women were followed for 4.1 years (median, range 0.0-8.9 years). White women developed less T2DM (12.5% vs 35.5%; P = .005) but had higher systolic (mean ± SD, 116 ± 13 vs 109 ± 11 mm Hg; P < .001) and diastolic (71 ± 9 vs 68 ± 7 mm Hg; P = .02) blood pressure, more smoking (35.4% vs 10.5%; P = .004), and more chorangiosis (52.1% vs 30.3%; P = .02) than nonwhite women.

CONCLUSIONS

Although more nonwhite women developed T2DM, more white women had chorangiosis, possibly secondary to the higher percentage of smokers among them. Further study is necessary to elucidate the relationship among chorangiosis, subsequent maternal T2DM, and race.

[Evaluation of intrauterine death: importance of examination of fetal, placental and maternal factors]

AIMS

Intrauterine death is a multifactorial major complication during pregnancy. In this retrospective analysis the pathological anatomical findings of fetuses and placentas as well as maternal factors were evaluated.

MATERIAL AND METHODS

A retrospective screening of post-mortem examinations, corresponding placental examinations and clinical data on maternal status (1998-2008) was carried out. A classification of all findings was made with the ReCoDe system and induced abortions and cases with incomplete data were excluded from the study.

RESULTS

A total of 84 pregnancies involving 87 fetuses (9 siblings) were evaluated. The median gestation age was 20 weeks (range 12-41). The evaluation based on the ReCoDe system revealed that intrauterine death was mainly associated with placental diseases (n = 63) and to a lesser extent with fetal malformations (n = 15) or maternal diseases (n = 4). Idiopathic cases were rare (n = 2).

CONCLUSIONS

Placental examination is important for explaining intrauterine death because in most cases an association with placental diseases can be found but fetal malformation and maternal diseases must be taken into account.

Hypoxic patterns of placental injury: a review

CONTEXT

In utero hypoxia is an important cause of perinatal morbidity and mortality and can be evaluated retrospectively to explain perinatal outcomes, to assess recurrence risk in subsequent pregnancies, and to investigate for medicolegal purposes by identification of many hypoxic placental lesions. Definitions of some placental hypoxic lesions have been applied relatively liberally, and many of them are frequently underreported. Objectives To present a comprehensive assessment of the criteria for diagnosing acute and chronic histologic features, patterns, and lesions of placental and fetal hypoxia and to discuss clinicopathologic associations and limitations of the use thereof. The significance of lesions that have been described relatively recently and are not yet widely used, such as laminar necrosis; excessive, extravillous trophoblasts; decidual multinucleate extravillous trophoblasts; and, most important, the patterns of diffuse chronic hypoxic preuterine, uterine, and postuterine placental injury and placental maturation defect, will be discussed.

DATA SOURCES

Literature review.

CONCLUSIONS

The placenta does not respond in a single way to hypoxia, and various placental hypoxic features should be explained within a clinical context. Because the placenta has a large reserve capacity, hypoxic lesions may not result in poor fetal condition or outcome. On the other hand, very acute, in utero, hypoxic events, followed by prompt delivery, may not be associated with placental pathology, and many poor perinatal outcomes can be explained by an etiology other than hypoxia. Nevertheless, assessment of placental hypoxic lesions is helpful for retrospective explanations of complications in pregnancy and in medicolegal investigation.

The feto-placental endothelium in pregnancy pathologies

This review aims to provide a comprehensive summary of the aspects of endothelial and vascular dysfunction in the feto-placental vasculature occurring in pregnancy pathologies. This endothelium is continuous with the fetal circulation. Its function and potential dysfunction in pathologies will have a profound impact on fetal development. Gestational diabetes mellitus represents one of these pathologies, in which its associated metabolic derangements will alter feto-placental endothelial functions. These, in turn, may result in functional changes of the placenta, which may entail impaired fetal development. By contrast, changes in the feto-placental vasculature observed in cases of fetal growth restriction and preeclampsia may be causative (fetal growth restriction) or secondary (preeclampsia) for the pathology.

Morphometric characteristics of placental villi in pregnant women with diabetes

We conducted a comparative morphological study of placentas from women with gestational diabetes and diabetes mellitus. Morphometry of histological preparations revealed similar type of changes in the studied parameters of placental villi in diabetes mellitus and gestational diabetes. The maximum deviation of the studied parameters from the control was noted in type 1 diabetes mellitus.

First trimester placental volume and three dimensional power doppler ultrasonography in type I diabetic pregnancies

OBJECTIVE

This study aimed to investigate the placental volume and three dimensional (3D) power Doppler vascularization in type I diabetic pregnancies during the first trimester

METHODS

3D-power Doppler ultrasonography of the placenta was performed at 11+0-13+6 weeks in 32 pregnancies complicated by type I diabetes. Placental volume, vascularization index (VI), flow index (FI), and vascularization flow index (VFI) were calculated using a standardized setting.

RESULTS

In nine pregnancies, a poor first trimester glycemic control was present as expressed by HbA1c levels  ≥ 7%, whereas in the remaining 23 mothers, the HbA1c concentrations were <7%. No differences were found in the placental volumes of diabetic mothers when compared with reference limits. 3D Doppler placental vascular indices were significantly higher in diabetic mothers (VI delta value 0.99, p=0.0012; FI delta value 0.64, p=0.0008; VFI delta value 1.28, p=0.0039) when compared with reference limits. Pregnancies with HbA1c ≥ 7% exhibited higher placental vascular indices when compared with diabetic mothers with better glycemic control.

CONCLUSIONS

In type I diabetic mothers, placental vascular indices are increased and these modifications are more evident in pregnancies with poor first trimester glycemic control.

The branching pattern of villous capillaries and structural changes of placental terminal villi in type 1 diabetes mellitus

Maternal diabetes is associated with changes of the placental structure. These changes include great variability of vascularity manifested by strikingly hypovascular as well as hypervascular terminal villi. In this paper, normal placental terminal villi and pathological villi of type 1 diabetic placentas were compared concerning the structure of villous stroma, spatial arrangement of villous capillary bed and quantitative assessment of capillary branching pattern. Formalin fixed and paraffin embedded specimens of 14 normal and 17 Type 1 diabetic term placentas were used for picrosirius staining, vimentin and desmin immunohistochemistry and confocal microscopy. 3D models of villi and villous capillaries were constructed from stacks of confocal optical sections. Hypervascular as well as hypovascular villi of diabetic placenta displayed changed structure of villous stroma, i.e. the collagen envelope around capillaries looked thinner and the network of collagen fibers seemed less dense. The desmin immunocytochemistry has shown that stromal cells of hypervascular as well as hypovascular villi appeared nearly or completely void of desmin filaments. In comparison with normal villi, capillaries of hypovascular villi had a smaller diameter and displayed a markedly wavy course whereas in hypervascular villi numerous capillaries occurred in reduced stroma and often had a large diameter. The quantitative assessment of capillary branching has shown that villous capillaries are more branched in diabetic placentas. It is concluded that type 1 maternal diabetes enhances the surface area of the capillary wall by elongation, enlargement of diameter and higher branching of villous capillaries and disrupts the stromal structure of terminal villi.

The morphometry of materno-fetal oxygen exchange barrier in a baboon model of obesity

INTRODUCTION

More than one-fourth of U.S. women are overweight; more than one-third are obese. Maternal obesity has been linked to an increased incidence of stillbirths, fetal macrosomia, fetal intrauterine growth restriction and pre-eclampsia. The placenta plays a key role in the nutrients and oxygen supply to the fetus. The data about structural changes in the placental villous membrane (VM), a major component of the feto-maternal nutrient and oxygen exchange barrier, during obesity are sparse and inconsistent. Our objective was to evaluate the morphometric changes in the placental exchange barrier in a baboon model of obesity.

MATERIALS AND METHODS

The previously described baboon model of maternal obesity was studied. We compared 4 obese to 4 non-obese baboons. Placental stereology with the use of transmission electron microscopy was performed to estimate VM oxygen diffusing capacities and morphometry.

RESULTS

The specific placental oxygen diffusing capacities per unit of fetal weight were similar in baboons and humans. Maternal leptin concentrations correlated negatively with placental basement membrane thickness (r = -0.78, p < 0.05), while fetal leptin levels correlated negatively with endothelial thickness of fetal capillaries (r = -0.78, p < 0.05). The total and specific villous membrane oxygen diffusing capacities were not different between the two groups.

CONCLUSION

To the best of our knowledge this is the first report of placental oxygen diffusing capacities and placental ultrastructural changes in a baboon model of obesity. Previously reported placental inflammation in maternal obesity is not associated with changes in the VM diffusing capacities and ultrastructure.

Circulatory and renal consequences of pregnancy in diabetic NOD mice

OBJECTIVES

Women with diabetes have elevated gestational risks for severe hemodynamic complications, including preeclampsia in mid- to late pregnancy. This study employed continuous, chronic radiotelemetry to compare the hemodynamic patterns in non-obese diabetic (NOD) mice who were overtly diabetic or normoglycemic throughout gestation. We hypothesized that overtly diabetic, pregnant NOD mice would develop gestational hypertension and provide understanding of mechanisms in progression of this pathology.

STUDY DESIGN

Telemeter-implanted, age-matched NOD females with and without diabetes were assessed for six hemodynamic parameters (mean, systolic, diastolic, pulse pressures, heart rate and activity) prior to mating, over pregnancy and over a 72 h post-partum interval. Urinalysis, serum biochemistry and renal histopathology were also conducted.

RESULTS

Pregnant, normoglycemic NOD mice had a hemodynamic profile similar to other inbred strains, despite insulitis. This pattern was characterized by an interval of pre-implantation stability, post implantation decline in arterial pressure to mid gestation, and then a rebound to pre-pregnancy baseline during later gestation. Overtly diabetic NOD mice had a blood pressure profile that was normal until mid-gestation then become mildly hypotensive (-7 mmHg, P < 0.05), severely bradycardic (-80 bpm, P < 0.01) and showed signs of acute kidney injury. Pups born to diabetic dams were viable but growth restricted, despite their mothers' failing health, which did not rebound post-partum (-10% pre-pregnancy pressure and HR, P < 0.05).

CONCLUSIONS

Pregnancy accelerates circulatory and renal pathologies in overtly diabetic NOD mice and is characterized by depressed arterial pressure from mid-gestation and birth of growth-restricted offspring.

Placental vascular dysfunction in diabetic pregnancies: intimations of fetal cardiovascular disease?

In the human placenta, the angioarchitecture of fetal vessels lying in maternal blood is useful for nutrient uptake, but it makes the synthesis, maturation and functioning of placental vessels vulnerable to any alterations in the fetal and maternal environment. This review discusses how the maternal diabetic milieu, and the resultant fetal hyperglycemia and hyperinsulinemia, may act together to produce an altered placental vascular phenotype, which includes increased angiogenesis, altered junctional maturity, increased vascular endothelial-like growth factor (VEGF), altered VEGF and insulin receptor profiles, and upregulation of genes involved in signal transduction, transcription and mitosis in placental endothelial cells. The placental vascular dysfunction does extend to other fetal vascular beds including endothelial cells from umbilical vessels, where there are reports of elevated basal iNOS activity and altered sensitivity to insulin. There is emerging evidence of epigenetic modulation of fetal endothelial genes in diabetes and long-term vascular consequences of this. Thus, placental vascular dysfunction in diabetes may be contributing to and describing disturbances in the fetal vasculature, which may produce an overt pathological response in later life if challenged with additional cardiovascular stresses.

Clinical associations with a placental diagnosis of delayed villous maturation: a retrospective study

Delayed villous maturation (DVM) is a spectrum of placental disease characterized by decreased tertiary villus formation, reduced vasculosyncytial membrane formation, and, in its more severe forms, increased large bullous villi. In some series it has been associated with an increased risk of stillbirth in the late third trimester, but overall there are few data on its significance. The aim of this study was to assess perinatal factors associated with, and the clinical significance of, the finding of DVM on placental histology. This was a retrospective study investigating all pregnancies with DVM diagnosed on placental histology in a tertiary level unit between December 2001 and August 2006. Over a 6-year period, 2915 placentas were triaged for histopathological assessment, representing 6.1% of all 48 054 deliveries in this time period. One hundred ninety (6.3%) of these selected cases showed DVM. Fifteen placentas from infants with less than 34 completed weeks of gestation were excluded, leaving 175 for further analysis. When compared with controls matched for gestation and delivering within the same time period (n  =  175), DVM was significantly associated with pregestational diabetes (8% vs 2.8%, P < .05; relative risk 2.8 [95% confidence interval 1.03-7.6]), gestational diabetes (8.6% vs 3.4%, P < 0.05; relative risk 2.5 [95% confidence interval 0.99-6.3]), and prenatal or intrapartum intrauterine death (8.6% vs 0%, P < 0.05). Delayed villous maturation is associated with both gestational and pregestational diabetes mellitus and with perinatal death.

Vascular dysfunction in the diabetic placenta: causes and consequences

The development and functioning of the human fetoplacental vascular system are vulnerable to the maternal diabetic milieu. These vessels are in direct continuum with the fetal vascular system and are therefore also vulnerable to fetal endocrine derangements. Increased angiogenesis, altered junctional maturity and molecular occupancy, together with increased leakiness, constitute a well-described phenotype of vessels in the Type 1 diabetic human placenta and can be related to increased levels of placental vascular endothelial growth factor. The causes of these observed changes, whether maternal hyperglycaemia or fetal hyperinsulinaemia, still remain to be shown in the human placenta. Mechanistic studies using different vascular systems have shown high glucose and insulin to have profound vascular effects, with elevations in vascular endothelial growth factor, nitric oxide and protein kinase C being behind alterations in junctional adhesion molecules such as occludin and vascular endothelial-cadherin and vascular leakage of albumin. The role of advanced glycation products and oxidative stress in this vascular pathology is also discussed. The altered molecular mechanisms underlying the vascular changes in the diabetic human placenta may reflect similar consequences of high glucose and hyperinsulinaemia.

Preeclampsia: 2-methoxyestradiol induces cytotrophoblast invasion and vascular development specifically under hypoxic conditions

Inadequate invasion of the uterus by cytotrophoblasts is speculated to result in pregnancy-induced disorders such as preeclampsia. However, the molecular mechanisms that govern appropriate invasion of cytotrophoblasts are unknown. Here, we demonstrate that under low-oxygen conditions (2.5% oxygen), 2-methoxyestradiol (2-ME), which is a metabolite of estradiol and is generated by catechol-o-methyltransferase (COMT), induces invasion of cytotrophoblasts into a naturally-derived, extracellular matrix. Neither low-oxygen conditions nor 2-ME alone induces the invasion of cytotrophoblasts in this system; however, low-oxygen conditions combined with 2-ME result in the appropriate invasion of cytotrophoblasts into the extracellular matrix. Cytotrophoblast invasion under these conditions is also associated with a decrease in the expression of hypoxia-inducible factor-1alpha (HIF-1alpha), transforming growth factor-beta3 (TGF-beta3), and tissue inhibitor of metalloproteinases-2 (TIMP-2). Pregnant COMT-deficient mice with hypoxic placentas and preeclampsia-like features demonstrate an up-regulation of HIF-1alpha, TGF-beta3, and TIMP-2 when compared with wild-type mice; normal levels are restored on administration of 2-ME, which also results in the resolution of preeclampsia-like features in these mice. Indeed, placentas from patients with preeclampsia reveal lower levels of COMT and higher levels of HIF-1alpha, TGF-beta3, and TIMP-2 when compared with those from normal pregnant women. We demonstrate that low-oxygen conditions of the placenta are a critical co-stimulator along with 2-ME for the proper invasion of cytotrophoblasts to facilitate appropriate vascular development and oxygenation during pregnancy.

Placental structure in type 1 diabetes: relation to fetal insulin, leptin, and IGF-I

OBJECTIVE

Alteration of placental structure may influence fetal overgrowth and complications of maternal diabetes. We examined the placenta in a cohort of offspring of mothers with type 1 diabetes (OT1DM) to assess structural changes and determine whether these were related to maternal A1C, fetal hematocrit, fetal hormonal, or metabolic axes.

RESEARCH DESIGN AND METHODS

Placental samples were analyzed using stereological techniques to quantify volumes and surface areas of key placental components in 88 OT1DM and 39 control subjects, and results related to maternal A1C and umbilical cord analytes (insulin, leptin, adiponectin, IGF-I, hematocrit, lipids, C-reactive protein, and interleukin-6).

RESULTS

Intervillous space volume was increased in OT1DM (OT1DM 250 + or - 81 cm(3) vs. control 217 + or - 65 cm(3); P = 0.02) with anisomorphic growth of villi (P = 0.025). The placentas showed a trend to increased weight (OT1DM 690 + or - 19 g; control 641 + or - 22 g; P = 0.08), but villous, nonparenchymal, trophoblast, and capillary volumes did not differ. Villous surface area, capillary surface area, membrane thickness, and calculated morphometric diffusing capacity were also similar in type 1 diabetic and control subjects. A1C at 26-34 weeks associated with birth weight (r = 0.27, P = 0.03), placental weight (r = 0.41, P = 0.0009), and intervillous space volume (r = 0.38, P = 0.0024). In multivariate analysis of cord parameters in OT1DM, fetal IGF-I emerged as a significant correlate of most components (intervillous space, villous, trophoblast, and capillary volumes, all P < 0.01). By contrast, fetal insulin was only independently associated with capillary surface area (positive, r(2) = 6.7%; P = 0.02).

CONCLUSIONS

There are minimal placental structural differences between OT1DM and control subjects. Fetal IGF-I but not fetal insulin emerges as a key correlate of placental substructural volumes, thereby facilitating feedback to the placenta regarding fetal metabolic demand.

The incidence of placental abnormalities, maternal and cord plasma malondialdehyde and vascular endothelial growth factor levels in women with gestational diabetes mellitus and nondiabetic controls

BACKGROUND/AIMS

To evaluate the incidence of placental abnormalities, cord plasma erythropoietin (EPO) levels and nucleated red blood cell (NRBC) counts, maternal and cord plasma malondialdehyde (MDA) and vascular endothelial growth factor (VEGF) levels in women with gestational diabetes mellitus (GDM) and nondiabetic controls.

METHODS

Twenty-two women with GDM, diagnosed according to the current criteria of the American Diabetes Association, were compared with 22 controls. Maternal and cord blood and placental samples were obtained from all pregnant women. Cord plasma EPO levels and NRBC counts, maternal and cord plasma MDA and VEGF levels were determined. Placental tissues were examined histologically.

RESULTS

Maternal and cord plasma levels of MDA and cord plasma EPO levels and NRBC counts were significantly higher in GDM pregnancies (p < 0.01). The presence of villous immaturity, chorangiosis and ischemia were significantly increased in the placentas of women with GDM (p < 0.05). The maternal and cord plasma levels of MDA increased (p = 0.007 and p = 0.001, respectively), whereas VEGF decreased (p = 0.046 and p = 0.001, respectively) with the presence of villous immaturity.

CONCLUSION

The complex process of villous development and maturity might be influenced by the maternal and fetal oxidative and angiogenetic milieu. The placenta that shows abnormalities in angiogenesis and maturation may lead to fetal hypoxia and compromise.

Aberrant endometrial features of pregnancy in diabetic NOD mice

OBJECTIVE

Pregnant diabetic women are at a 4-12 times higher risk for preeclampsia, an urgent acute-onset complication of mid- to late gestation, than normal pregnant women. Hallmarks of preeclampsia are hypertension, proteinuria, and incomplete modification of endometrial spiral arteries. Transient proangiogenic lymphocytes called uterine natural killer (uNK) cells are implicated in human and rodent spiral artery modification. We studied mid- to late gestations in spontaneously type 1 diabetic NOD mice to investigate whether diabetes alters uNK cell homing and/or function.

RESEARCH DESIGN AND METHODS

Normoglycemic, pre-diabetic, and diabetic NOD mice and controls were mated. Lymphocytes and endometrial endothelium and decidua were studied histologically and in functional assays.

RESULTS

Conception accelerated progression to overt diabetes in NOD females who had limited spiral artery development, heavier placentas, and lighter fetuses displaying numerous birth defects compared with controls. UNK cell numbers were reduced in the decidua basalis of diabetic females, whereas interferon-gamma production was elevated. In diabetic NOD mice, decidual expression of the mucosal vascular addressin cell adhesion molecule (MAdCAM)-1 was aberrant in position, whereas vascular cell adhesion molecule (VCAM)-1 expression was reduced. Assays of lymphocyte adhesion to tissue sections under shear forces indicated that diabetes compromises the potential homing functions of both endometrial endothelium and peripheral NK cells.

CONCLUSIONS

In diabetes, gestational endometrium has immune and vascular defects that likely contribute to murine fetal loss and birth defects. Analogous problems and preeclampsia in diabetic women may involve similar mechanisms.