Identification of novel cell survival regulation in diabetic embryopathy via phospholipidomic profiling.

Diabetes mellitus in early pregnancy causes birth defects by disturbing metabolic homeostasis and increasing programmed cell death in the embryo. Over-activation of phospholipase Cß3 and γ1 suggests disturbed phospholipid metabolism, which is an important in regulation of cell signaling and activity. Metabolomic examinations reveal significant changes in the profile of phospholipid metabolism. Among the metabolites, levels of phosphatidylinositol bisphosphate (PIP2) are increased. PIP2 effector PTEN (phosphatase and tensin homolog deleted on chromosome 10) is activated. Activation of protein kinase Bα (PKBα, or AKT1) and mTOR (mechanistic target of rapamycin) is decreased. Inhibition of PLCs and PTEN suppresses over-generation of reactive oxygen species and inhibition of PLCs prevents fragmentation of mitochondria in neural stem cells cultured in high glucose. These observations suggest that maternal hyperglycemia disrupts phospholipid metabolism, leading to perturbation of mitochondrial dynamics and redox homeostasis and suppression of the PKB-mTOR cell survival signaling in the embryos.

Decreased fetal cardiac performance in the first trimester correlates with hyperglycemia in pregestational maternal diabetes.

OBJECTIVE: In-vitro animal studies suggest that high glucose levels impair fetal cardiac function early in gestation. We aimed to study whether evidence of first-trimester myocardial dysfunction can be detected in fetuses of women with pregestational diabetes mellitus. METHODS: Women with diabetes mellitus underwent fetal echocardiography at 11-14 weeks' gestational age. In fetuses with normal anatomy, the cardiac preload, diastolic function, global myocardial performance and placental afterload were studied by Doppler of the ductus venosus (DV), mitral and tricuspid early/atrial (E/A) ratios, left and right ventricular myocardial performance index (MPI) and umbilical artery (UA) Doppler, respectively. Cases were matched for gestational age and UA and DV Doppler with controls that had no diabetes mellitus. RESULTS: Sixty-three singleton diabetic pregnancies were matched with 63 controls. Mean gestational age at enrollment was 12.6 (range, 11.1-13.6) weeks. Diabetic mothers had moderate to poor glycemic control (median (range) glycosylated hemoglobin A1 (HbA1c), 7.5 (5.1-12.7)%, and the HbA1c level was ≥ 7% in 37 (59%)). Fetuses of diabetic mothers exhibited worse measures of diastolic dysfunction: the isovolumetric relaxation time (IRT) was significantly prolonged (left ventricle: 36.9 ± 7.4 ms vs. 45.8 ± 6.8 ms; right ventricle: 35.6 ± 8 ms vs. 46.4 ± 7.3 ms, P < 0.0001 for both). The mitral E/A ratio was lower in diabetics (0.55 ± 0.06 vs. 0.51 ± 0.08, P = 0.03), and the global myocardial performance was lower in both ventricles (left ventricle MPI: 0.5 ± 0.08; right ventricle MPI: 0.52 ± 0.08, P = 0.03 and P < 0.0001, respectively). This lower global myocardial performance was caused by a prolonged myocardial relaxation time, which was most marked in diabetics with an HbA1c of ≥ 7% (P < 0.001 vs. controls for both ventricles). There were no significant correlations between cardiac Doppler parameters and DV, UA indices and fetal heart rate (P > 0.05 for all). CONCLUSIONS: Fetuses of poorly controlled diabetic mothers demonstrate significant differences in first-trimester diastolic myocardial function compared with non-diabetic controls. The decrease in myocardial performance is more marked with increasing HbA1c and appears to be independent of preload and afterload. The ability to document these cardiac functional changes this early in pregnancy opens potential new avenues to understand the consequences of maternal glycemic status.

At diabetes-like concentration, glucose down-regulates the placental serotonin transport system in a cell-cycle-dependent manner.

Serotonin [5-hydroxytryptamine (5HT)] is a vasoconstrictor that also acts as a developmental signal early in embryogenesis. The 5HT transporter (SERT) on the membranes of the placental trophoblast cells controls 5HT levels in the maternal bloodstream to maintain stable transplacental blood flow and simultaneously provide 5HT to the embryo. The 5HT uptake rate of placental SERT is important for both the mother and the developing embryo. The impact of glucose on the placental SERT system during diabetic pregnancy is not known. The present in vitro study investigated this important issue in human placental choriocarcinoma (JAR) cells that were cultured for 24-96 h in a medium containing either 5.5 (physiologic concentration) or 25 mmol/L D-glucose (diabetic-like concentration). The 5HT uptake rates of the cultured cells were not altered at exogenous D-glucose concentrations in the range of 5.5-15 mmol/L, but were decreased significantly at a diabetic-like concentration (>or=25 mmol/L). To understand better the role of glucose on the placental 5HT system, we first characterized SERT in JAR cells at different cell-cycle phases and then determined the expression levels of SERT on the plasma membrane and in the intracellular pools of JAR cells at the late-S and G2 phases, where the uptake rates were decreased 73% under diabetic-like glucose concentrations. Finally, the importance of self-association of SERT molecules was examined. In JAR cells co-expressing Flag- and myc-tagged SERT, myc-antibody precipitated 70% of Flag-SERT, indicating that a large percentage of SERT proteins exist as oligomers in situ. Under diabetic conditions, myc-antibody no longer precipitated Flag-SERT, suggesting a disruption in the aggregation of SERT molecules. Therefore, we propose that under uncontrolled diabetic conditions, glucose down-regulates 5HT uptake rates of placental SERT by interfering with its functional expression in a cell-cycle-dependent manner.

Cerebellar growth in normal fetuses of multiple gestations.

OBJECTIVE: The purpose of this study was to compare the cerebellar growth in twin and triplet gestations with cerebellar growth in singleton pregnancies. METHODOLOGY: An ultrasound study was conducted in a population of normal pregnant women with singleton, twin and triplet gestations. Routine ultrasound examinations were performed in healthy pregnant women: 951 women with singleton pregnancies; 151 with twin gestations; and 28 with triplet gestations. Although multiple biometric parameters were measured throughout the course of pregnancy, in this study a single measurement (the last measurement before delivery) of the transverse cerebellar diameter (TCD) was used from each patient for statistical analysis. Growth of the TCD was determined in the multiple gestations and compared with growth in singleton pregnancies. RESULTS: A statistically significant relationship was found between TCD and gestational age in all three groups (singleton, twin A and B, and triplets) respectively: R2 = 0.963; R2 = 0.980; R2 = 0.977. No statistical difference was found between the three sets of normative measurements. CONCLUSIONS: There was no significant difference observed in cerebellar growth among singleton and multiple gestations. Therefore, nomograms previously established for singleton pregnancies may be useful to assess growth in multifetal pregnancies.

Intensive interventional maternity care reduces infant morbidity and hospital costs.

OBJECTIVE: The purpose of this study was to introduce an intensive interventional maternity care program, called the Temple Infant and Parent Support Services (TIPSS) program, and to determine whether comprehensive maternal and infant care would reduce the high rate of infant morbidity and mortality. METHODS: The TIPSS program was comprehensive, offering multidisciplinary services that were family focused and community based. Program services included community outreach, health education, as well as clinical care for the entire family. The effect of this program was evaluated among a very high-risk group of women who were recruited into care versus a control group of high-risk patients from the same neighborhood who voluntarily sought care at the Temple University School of Medicine. Outcome parameters evaluated included gestational age at delivery, birth weight, neonatal intensive care admission, infant death and cost of infant care. RESULTS: Among the TIPSS study group, 5.2% of infants were below 2500 g versus 11% in the control group (p < 0.05). Similarly, preterm deliveries occurred in 4.2% and 12% of the study and control groups, respectively (p < 0.005). Other significant differences observed included the number of prenatal visits (p < 0.001), maternal weight gain (p < 0.05) and admission to the neonatal intensive care unit (2% vs. 6.6%; p < 0.05). The reduced admission rate among neonates from the TIPSS program resulted in significant cost savings: $2849 for neonates in the study group versus $8499 for those in the control group. This corresponds to a $5560 savings per infant born to mothers cared for in the TIPSS study group. CONCLUSIONS: The Temple Infant and Parent Support Services program demonstrated that infant morbidity could be reduced when a comprehensive prenatal program was made available to indigent patients, even if there were multiple factors that placed the mother and her infant at high risk for complications.

Aberrant patterns of cellular communication in diabetes-induced embryopathy. I. Membrane signalling.

OBJECTIVE: Our purpose was to investigate the role of membrane signalling in the mechanism of diabetes-induced embryopathy. METHODS: Three groups of 70-90-day-old Sprague-Dawley rats were employed in our study: group 1 was normal control rats receiving a normal diet; group 2 represented experimentally induced diabetic rats with malformed offspring (intravenous injection of 65 mg/kg streptozotocin on pregnancy day 6) and group 3 included streptozotocin-induced diabetic rats with normal offspring. Embryos were examined on day 12 under light microscopy, categorized as morphologically normal or defective, and yolk sac cells were harvested from each group. Activities of ERK1 and 2, Raf-1, JNK1 and 2 in yolk sac cells were analyzed by Western blot with primary antibodies specific to the phosphorylated kinases, respectively. RESULTS: A strong link between hyperglycemia and congenital malformations was confirmed. Key mitogen-activated protein kinases serve as syllabic intermediates: increased activities of Jun-amino-terminal kinase (JNK1 and 2) and decreased activities of extracellular signal-regulated kinase (ERK1 and 2) were observed during hyperglycemia-induced embryopathy. CONCLUSIONS: Poorly controlled maternal diabetes results in embryopathy which is mediated via a pattern of aberrant cellular communication manifested by both macroscopic and microscopic membrane injury.

Blood glucose monitoring in gestational diabetes mellitus: 1- versus 2-h blood glucose determinations.

Gestational diabetes mellitus is a common disorder of pregnancy affecting 3-5% of pregnant women. Although significant controversy exists regarding its diagnosis and treatment, macrosomia has been consistently associated with maternal hyperglycemia. Numerous studies have addressed different approaches to monitoring blood glucose levels, but data on the ideal timing for postprandial determinations are scarce. This article reviews current recommendations and recent findings on the implications of 1- versus 2-h blood glucose determinations in pregnant women with gestational diabetes mellitus. Preliminary studies have shown a statistically significant reduction in macrosomia and decreased need for emergency Cesarean section among women monitored 1 h after meals. Until larger studies confirm these benefits, compliance is of the utmost importance for successful treatment. Therefore, patient preferences should be considered in planning a monitoring strategy.

Self-monitoring of blood glucose in gestational diabetes.

Numerous studies have clearly demonstrated a significant association between maternal glycemic control and adverse outcomes in pregnancies complicated by gestational diabetes. However, despite our understanding of the importance of stringent glucose control in the management of these pregnancies, the definition of optimal glycemic control and monitoring protocols have yet to be firmly established. This article reviews current evidence regarding the efficacy of self-monitoring of blood glucose in the management of gestational diabetes. The role of various self-monitoring protocols and their impact on outcome is also explored. Areas where further investigations are needed in terms of glucose assessment are highlighted.

Role of diltiazem in pregnant women with chronic renal disease.

OBJECTIVE: To determine whether diltiazem therapy decreases proteinuria during pregnancy in women with chronic renal disease, resulting in decreased risk of pre-eclampsia, preterm delivery and intrauterine fetal growth restriction. METHODS: We undertook retrospective data collection by chart review of pregnant women with chronic renal disease. Women treated with and without diltiazem were compared by independent t test analysis. RESULTS: Seven women were eligible for inclusion in the study. Individual patient trends revealed decreased or attenuated increase in proteinuria across gestation with diltiazem therapy. Mean arterial pressure was also decreased in the therapy group compared to increased pressure in the third trimester in the group with no therapy. The incidence of fetal growth restriction and need for labor induction were lower in the diltiazem-treated group. CONCLUSIONS: Diltiazem, a non-dihydropyridine calcium channel antagonist, decreases proteinuria and preserves renal structure and function and should be considered an alternative to angiotensin converting enzyme inhibitors in pregnancy in women with chronic renal disease.

One or two hours postprandial glucose measurements: are they the same?

OBJECTIVE: This study was undertaken to compare the rate of abnormal glucose levels measured after 1 hour (>140 mg%) with those measured after 2 hours (>120 mg%) postprandially in women with gestational diabetes mellitus (GDM). STUDY DESIGN: Sixty-eight women were included in this study. All had GDM based on the criteria of Carpenter-Coustan. Women with fasting glucose levels of 105 mg% or more were excluded from the study. All women were initially treated by diet. All women measured daily capillary blood glucose levels when fasting as well as 1 hour and 2 hours postprandially for 1 week, immediately after diagnosis of GDM. Glucose levels were obtained by memory-based glucometers. All women were followed in a specialized gestational-diabetes clinic throughout the pregnancy. Insulin therapy was started on an individual basis according to common clinical criteria. Epidemiologic and perinatal data were collected from medical charts. RESULTS: The average age of the women was 30.8 +/- 5.4 years. Thirty-five percent of participants were primipara. The mean gestational age at diagnosis was 28.8 +/- 5.4 weeks. Glucose measurements included 618 readings during fasting and 2730 either 1 hour or 2 hours postprandial. Rates of abnormal glucose (>95 mg% when fasting; >140 mg% 1 hour or >120 mg% 2 hours after each meal) per person were the following: fasting, 27.1% abnormal glucose measurements; postbreakfast, 22.4% abnormal levels after 1 and 8.5% after 2 hours (P < .01); postlunch, 16.4% abnormal levels after 1 hour and 18.2% after 2 hours (not significant); postdinner, 16.3% abnormal levels after 1 hour and 30.1% after 2 hours (P < .01). CONCLUSION: The rate of abnormal values was 2.5-fold greater 1 hour postbreakfast than 2 hours postbreakfast, in contrast to an opposite ratio of a 2-fold increase in the rate of abnormal values 2 hours postdinner versus 1 hour postdinner. Therefore, differential measurement (1 hour after breakfast and 2 hours after dinner) might impose stricter criteria for controlling blood glucose levels. Further clinical research should explore whether differential measurements might reduce the rate of diabetes-associated complications.

Fetal serum levels of insulin, growth hormone and insulin-like growth factor-I in concordant and discordant twin gestations.

OBJECTIVE: To examine the role of insulin, growth hormone and insulin-like growth factor (IGF)-I in concordant and discordant twin pairs. METHODS: Umbilical cord serum samples were obtained from 20 twin pairs with weight discordancy (intertwin birth weight difference > 20%) and from 20 concordant twins (intertwin birth weight difference < 20%), both groups of similar gestational age, gravidity, and parity. The serum samples were analyzed for the levels of IGF-I, growth hormone and insulin in both maternal and fetal compartments. RESULTS: Among the group of discordant twins, the normally grown twin, in all cases, had significantly higher cord serum IGF-I levels than their growth-restricted co-twin (108 +/- 73 ng/ml vs. 39 +/- 24 ng/ml; p < 0.01). There were no significant intertwin differences in the cord blood IGF-I levels in the concordant twin pairs (87 +/- 44 vs. 88 +/- 48 ng/ml; p = 0.986). Insulin and growth hormone levels did not correlate with intertwin birth weight differences. CONCLUSION: These data demonstrate that IGF-I is important in the regulation of both normal and restricted fetal growth in utero, and its action appears to be, at least in part, through an endocrine action. The precise role of growth hormone and insulin in fetal growth restriction remains uncertain.

To screen or not to screen for gestational diabetes mellitus. The clinical quagmire.

Although there continues to be a lack of agreement about the most appropriate way to screen for GDM, screening remains the standard of care in this country. Universal screening of all pregnant women maximizes sensitivity but has significant financial implications because of its increased costs. Additional studies are needed that apply cost-analysis to various screening protocols to identify cost-effective screening strategies.

The fetal superior cerebellar vermian width in normal, growth-restricted and macrosomic fetuses.

OBJECTIVES: To obtain dimensions of the fetal superior cerebellar vermian width as a basis for further studies and for comparisons with deviation in growth. STUDY DESIGN: The study group included 266 normal pregnant women from 20 to 37 weeks of gestation. Several biometric measurements were obtained throughout pregnancy, including the fetal superior cerebellar vermian width. Forty-three growth-restricted and 30 macrosomic fetuses were included in this study. RESULTS: A linear growth function was observed between the superior cerebellar vermian width and gestational age (GA) (R = 0.859; p < 0.00001; y = -4.033 + 0.416 x GA), transverse cerebellar diameter (TCD) (R = 0.870; p < 0.00001; y = 0.404 + 0.223 x TCD), biparietal diameter (BPD) (R = 0.823; p < 0.00001; y = -3.086 + 0.155 x BPD), head circumference (HC) (R = 0.82; p < 0.00001; y = -3.21 + 0.434 x HC), femoral length (FL) (R = 0.843; p < 0.00001; y = -1.75 + 0.184 x FL) and humeral length (HL) (R = 0.824; p < 0.00001; y = -2.691 + 0.223 x HL). The ratio between the superior cerebellar vermian width and the transverse cerebellar diameter remained constant throughout gestation. In all 43 growth-restricted and the 30 macrosomic fetuses, the dimensions of the fetal superior cerebellar vermian width remained within the normal range for the indexed gestational age. CONCLUSION: These results provide normative data for the fetal superior cerebellar vermian width in various dimensions and across gestational ages. In addition, growth of the superior cerebellar vermis remained normal in growth-restricted as well as macrosomic fetuses. Therefore, cerebellar vermian growth may be used adjunctively as a standard against which deviant fetal growth may be compared when precise gestational age determination is necessary.

Insulin secretion during and after pregnancy in patients with gestational diabetes mellitus.

We have determined prehepatic insulin secretion rates (ISRs) in seven patients with gestational diabetes mellitus (GDM) and in eight age- and weight-matched nondiabetic pregnant women during late gestation (third trimester) and again postpartum. Plasma glucose concentrations were raised to approximately 8.9 mM with iv glucose (hyperglycemic clamping), and ISRs were determined by deconvolution of peripheral C-peptide concentrations using C-peptide kinetic parameters that were obtained in every patient during late gestation and again postpartum. Plasma insulin levels were measured by RIA with an antibody with minimal (<0.2%) cross-reactivity with proinsulin. During late gestation, women with GDM were more insulin resistant than nondiabetic controls and had significantly lower ISRs (689 vs. 849 pmol/min, P < 0.05) and glucose uptake rates (30.6 vs. 49.4 micromol/kg.min, P < 0.05) in response to hyperglycemia. Postpartum, ISRs and insulin resistance decreased in women with GDM and controls (ISR by 43% and 43%, respectively, and insulin resistance by 75% and 118%, respectively), and both groups had similar ISRs (352 vs. 408 pmol/min, nonsignificant). Women with GDM, however, continued to be more insulin resistant than controls. In summary, patients with GDM during late pregnancy not only had severe deficiencies in ISR but, in addition, were more insulin resistant than controls. Postpartum, insulin resistance and ISRs (and plasma insulin levels) improved in both groups, and ISRs (and plasma insulin levels) were no longer significantly different in patients with GDM and controls. Insulin resistance, however, remained higher in women with GDM, and their glucose uptake remained lower. We concluded that the women with GDM had a major ss-cell defect that made it impossible for them to compensate for their increased level of insulin resistance, which occurred during late pregnancy.

Cord leptin level and fetal macrosomia.

OBJECTIVE: To determine the relationships among serum leptin, insulin-like growth factor-I, and insulin levels in large for gestational age (LGA) infants. METHODS: Serum samples were collected from maternal veins and umbilical arteries of 52 consecutive, term, LGA neonates of nondiabetic mothers. Maternal and neonatal serum samples were analyzed for levels of leptin, insulin-like growth factor-I, and insulin by specific radioimmunoassays. Multiple regression analysis was used to determine independent risk factors for fetal macrosomia. RESULTS: The independent risk factor significantly associated with fetal macrosomia was umbilical cord leptin concentration (P <.01, beta = 0.59). There was a statistically significant correlation between umbilical cord leptin and insulin-like growth factor-I levels and birth weight (r = 0.51, P <.01; r = 0.37, P <.01; respectively). The correlation between umbilical cord insulin levels and birth weight was not statistically significant (r = 0.06, P =.63), nor was that between maternal body mass index and birth weight (r = 0.09, P =.50). CONCLUSION: Our data showed that umbilical cord leptin concentration was an independent risk factor for fetal macrosomia.

Factors associated with fetal macrosomia in offspring of gestational diabetic women.

OBJECTIVE: To determine whether there is a relationship between birthweight and interval between 1-h and 3-h glucose tolerance test (GTT) as well as other factors. METHODS: We performed a retrospective analysis of our computerized diabetes database for the years 1992-1997. Ninety-four women with gestational diabetes fulfilled the inclusion criteria (i.e., singleton gestation, term delivery, absence of medical conditions, and known interval between 1-h and 3-h GTT). They were evaluated based on prepregnancy body mass index (BMI), mean glucose values, interval between diagnostic testing, and gestational age of 3-h GTT. RESULTS: Subjects with GDM had a mean glucose value of 96.8 mg/dl and average prepregnancy BMI of 29.3 kg/m2. When GDM subjects with and without macrosomic infants were compared, mean glucose values (97.4 vs. 96.6 mg/dl) and mean interval (18.1 vs. 17.0 days) between diagnostic testing did not significantly differ. However, maternal prepregnancy BMI was higher in the group of women who gave birth to macrosomic infants (32.2 vs. 28.22 kg/m2, P = 0.008). Using stepwise multiple regression, maternal prepregnancy BMI was the only variable found to be predictive of macrosomia. CONCLUSION: We were unable to show a statistical relationship between interval of diagnostic testing and rate of macrosomia. However, we demonstrated a clear relationship between maternal BMI and infant birthweight.

Neonatal transverse cerebellar diameter in normal and growth-restricted infants.

OBJECTIVE: To assess the transverse cerebellar diameter (TCD) in preterm and term neonates with normal growth or growth restriction. METHODS: TCD was sonographically measured after birth in 404 neonates born between 23 and 42 weeks of gestation. The study included two groups: Group 1: 334 appropriately grown for gestational age (AGA) neonates (both birthweight (BW) and head circumference (HC) were between the 3rd and 97th centiles), which were subdivided into two subgroups according to the HC measurements. Group 2: 70 small for gestational age (SGA) neonates (BW <3rd centile), were further divided into three subgroups according to HC measurements. RESULTS: In Group 1 of AGA neonates, a linear growth function was observed between the TCD and GA (R = 0.914, P < 0.00001, TCD = 0.279 + 0.142 X GA), and between TCD and HC (R = 0.886, P < 0.00001, TCD = -0.333 + 1.777 X HC). The percentage of neonates with normal TCD (> or =10th centile) was more than 85% of the AGA and asymmetric SGA subgroups, and 60.7% of the microcephalic SGA subgroup (P < 0.02). CONCLUSIONS: This study provides normative data of neonatal TCD across gestational age. TCD measurement via sonography is a new adjunctive criterion for objectively assessing gestational age in infants when a precise determination of gestational age is necessary. This is very important since utility of the TCD is effective for both AGA and asymmetric SGA infants.

Effect of medical therapy on progressive nephropathy: influence of pregnancy, diabetes and hypertension.

Nephropathy is a complication of diabetes mellitus that can affect women in their reproductive years. This article reviews the effects on treatment on the main factors associated with short- and long-term complications in pregnant women with diabetic nephropathy. Tight glycemic control, adequate treatment of elevated blood pressure, and renal function in early pregnancy are the most significant predictors of maternal and perinatal outcomes. Contemporary methods of perinatal care and adequate treatment of blood pressure allow fetal survival rates of 95%. Furthermore, pregnancy per se does not appear to worsen the natural progression to end-stage renal disease for most women with renal insufficiency. However, patients with moderate to severe renal impairment may experience acceleration of renal disease.