And what about epidermal growth factor (EGF) as the bridge between survivin and cardiac remodelling?

Maternal glycoregulation in pregnancies complicated by diabetes mellitus in the prediction of fetal echography findings and perinatal outcomes

AIM

We aimed to determine maternal hemoglobin A1c (HbA1c) levels and pregestational body mass index (BMI) as the predictors of glycemic control and its importance for fetal echography findings and perinatal outcomes in pregnancies complicated by diabetes mellitus (DM).

METHODS

Our intention was to evaluate how BMI and HbA1c levels might be used to predict fetal interventricular septum (IVS) thickness, atrioventricular inflow early diastole (E)/ atrial systole (A) velocity ratio, and perinatal outcomes. Patients in the 38th gestational week were divided into three groups according to their insulin therapy: (i) patients with gestational diabetes mellitus (GDM) treated only with dietary changes (GDM group, n = 32); (ii) patients with GDM treated with insulin therapy (DM2 group, n = 27); and (iii) patients with type 1 DM (DM1 group, n = 22).

RESULTS

In the DM1 group, we found statistically significant correlations between BMI and IVS thickness (P = 0.036), HbA1c and IVS thickness, as well as the mitral E/A velocity ratio (P = 0.013 vs P = 0.007). In this group, HbA1c showed a statistically significant correlation to neonatal birth weight (P = 0.037) and BMI influenced on appearance respiratory distress syndrome in neonates in DM1 group (P = 0.027). The values of HbA1c predict neonatal respiratory distress syndrome in DM2 and GDM groups (P = 0.036).

CONCLUSION

As good predictors of maternal glycoregulation, BMI and HbA1c levels determine fetal echography findings as well as neonatal outcomes in pregnancies complicated by DM.

Prediction of Fetal Hypertrophic Cardiomyopathy in Diabetic Pregnancies Compared with Postnatal Outcome

OBJECTIVE

The aim of this study was to estimate the accuracy of prenatal assessment of interventricular septum (IVS) thickness, right myocardial wall thickness (RMWT), and left myocardial wall thickness (LMWT) by two-dimensional (2D) ultrasound for the prediction of perinatal mortality and postnatal diagnosis of hypertrophic cardiomyopathy (HCM) among diabetic pregnant women.

SUBJECTS AND METHODS

A total of 120 diabetic pregnant women at 35 weeks or more were enrolled in this study from January 1, 2012, to June 30, 2014, at Ain Shams Maternity Hospital, Cairo, Egypt. The 2D ultrasound was done once for all the participants at the time of recruitment; IVS thickness, RMWT, and LMWT were measured. The glycosylated hemoglobin (HbA1c) levels of the participants were recorded. Neonatal assessment including postnatal echocardiography was done after 48 hours. Postnatal results were compared with the prenatal predictive results.

RESULTS

Higher thickness values for IVS, RMW, and LMW were obtained in the uncontrolled diabetic cases (HbA1c > 6.5%) than in the controlled diabetic cases (HbA1c < 6.5%; P < 0.01). Of the included 120 neonates, 10 (8.3%) were stillborn, 99 (82.5%) had a five-minute Apgar score ≥7, and 4 (3.3%) had a five-minute Apgar score ≤3. The four neonates with severe neonatal distress died after admission to neonatal intensive care unit within one week after delivery. Out of 110 live-born neonates, 4 (3.6%) neonates had a low ejection fraction (EF) (<50%) due to HCM; of them 2 (1.8%) died within one week after delivery, while 2 (1.8%) survived. Another two (1.8%) neonates died from severe respiratory distress syndrome. A cutoff value of ≥4.5 mm for prenatal IVS thickness was predictive of neonatal distress due to HCM with a sensitivity of 82%, specificity of 68%, and diagnostic accuracy of 72%. A cutoff value of <1.18 for the ratio of IVS thickness to LMWT had a sensitivity of 82%, specificity of 72%, and diagnostic accuracy of 74% for the prediction of neonatal distress due to HCM. In this study, 8 of the 10 fetuses with intrauterine demise and the 2 neonates who died within one week after delivery due to heart failure had a prenatal IVS thickness of ≥4.5 mm, while 7 of the 10 fetuses with intrauterine demise and the 2 neonates who died postnatal from heart failure had a prenatal IVS thickness to LMWT ratio of ≤1.18.

CONCLUSION

A prenatal IVS thickness of ≥4.5 mm or an IVS/LMWT ratio of ≤1.18 seems to be predictive of HCM and is associated with almost twofold higher risk of intrauterine fetal death and almost threefold higher risk of possibly relevant perinatal mortality.

EGFR inhibition protects cardiac damage and remodeling through attenuating oxidative stress in STZ-induced diabetic mouse model

Diabetes mellitus is strongly associated with cardiomyopathy. The underlying mechanisms for the development of diabetic cardiomyopathy are complex and not completely understood. Recent studies showed that epidermal growth factor receptors (EGFRs) are involved in diabetes-induced cardiac injury. However, the role of EGFR in the diabetic heart has yet to be confirmed. The aim of the present study is to further determine the role of EGRF in the pathogenesis of diabetic heart injury. The type 1 diabetic mice induced by streptozotocin were treated with EGFR inhibitors (AG1478 and 451) for 8 weeks, respectively. It was observed that diabetes induced phospohorylation of EGFR and AKT, increased cardiac ROS levels, and ultimately led to cardiac remodeling including cardiac hypertrophy, disorganization, apoptosis, and fibrosis, while all these molecular and pathological alterations were attenuated by the treatment with EGFR inhibitors. In vitro, either pharmacological inhibition of EGFR/AKT or sh-RNA silencing of EGFR significantly inhibited high concentration glucose (HG)-induced ROS generation and subsequently cell apoptosis in both cardiac H9C2 cells and primary rat cardiomyocytes, respectively. The ROS reduction by EGFR inhibitor was associated with the decreased NADPH oxidase activity and expression in H9c2 cells. HG-induced cardiomyocyte injuries were also reduced by NAC, an inhibitor of ROS. This study provides evidence that EGFR has a key role in the pathogenesis of STZ-induced diabetic cardiac damage and remodeling via ROS generation, and suggests that EGFR may be a potential target in treating diabetic cardiomyopathy.

The role of epidermal growth factor receptor in diabetes-induced cardiac dysfunction

The incidence of diabetes mellitus is increasing rapidly and set to reach near epidemic proportions with the latest estimates suggesting that by 2030 there will be over 550 million people with this debilitating disease. Cardiovascular complications and dysfunctions are three- to eight-folds more likely in diabetic patients and are major causes of increased mortality. The exact underlying mechanisms for the development of complications of the diabetic heart are poorly understood and may involve multiple signaling pathways that are affected by hyperglycemia. This focused article reviews the recent evidence for a possible dual role of epidermal growth factor receptor signaling in diabetes-induced cardiac dysfunction.