Expression of VEGF and CD68 in the Placenta of Gestational Diabetic Mothers (Immunohistochemistry and Ultrastructural Study)

The Placental Role in Gestational Diabetes Mellitus: A Molecular Perspective

During pregnancy, women undergo several metabolic changes to guarantee an adequate supply of glucose to the foetus. These metabolic modifications develop what is known as physiological insulin resistance. When this process is altered, however, gestational diabetes mellitus (GDM) occurs. GDM is a multifactorial disease, and genetic and environmental factors play a crucial role in its aetiopathogenesis. GDM has been linked to both macroscopic and molecular alterations in placental tissues that affect placental physiology. This review summarizes the role of the placenta in the development of GDM from a molecular perspective, including hormonal and pro-inflammatory changes. Inflammation and hormonal imbalance, the characteristics dominating the GDM microenvironment, are responsible for placental changes in size and vascularity, leading to dysregulation in maternal and foetal circulations and to complications in the newborn. In conclusion, since the hormonal mechanisms operating in GDM have not been fully elucidated, more research should be done to improve the quality of life of patients with GDM and their future children.

CD68 expression in the placenta of gestational diabetic mothers: A case-control study

Background

Gestational diabetes mellitus (GDM) is defined as any degree of glucose intolerance with the onset or first recognition during pregnancy and is the most common metabolic complication of pregnancy. Significant maternal and fetal complications can result from undiagnosed or inadequately treated GDM.

Aim

To investigate the difference in the expression of the CD-68 marker in the Hofbauer cells (HCs) and their distribution within the villi in the placentas of diabetic and non-diabetic mothers.

Materials and Methods

Sixty placentas were included in the study, 30 as controls and 30 from mothers with diagnosed GDM as cases. Full-thickness cross sections of placentas were obtained. Tissue processing was done, followed by haematoxylin and eosin (H&E). A study of CD68 markers (placental macrophages) was done using standard protocols of immunohistochemistry.

Statistical Analysis

Frequencies and percentages of Hofbauer cells (HCs) found in case and control placental tissue were calculated. Student's t-test was used to compare two groups using SPSS 13.0 software. When P is 0.0001, differences were considered statistically significant.

Results and Conclusion

We studied the distribution and number of fetal macrophages (CD68+) in diabetic and non-diabetic placentas. The immunostained CD68+ cell count was identified to be significantly higher in the GDM placenta. In relation to fetal blood vessels in the villus stroma of the GDM placenta in comparison to control, CD68+ cells were found more frequently. This study shows a significant increase in the number of Hofbauer cells in the placenta of mothers with GDM in comparison to control (P < 0.0001). An increase in macrophages in these placentae might be related to the protective mechanism against inflammation. Further studies are required to investigate the mechanism in detail.

Placental structural abnormalities in gestational diabetes and when they develop: A scoping review

Gestational diabetes mellitus (GDM) is defined as diabetes with onset or first recognition during gestation. It is a common complication of pregnancy that has become more prevalent over the past few decades. Abnormalities in fetal growth, including increased incidence of both large and small for gestational age babies, suggest placental dysfunction. The major goal of this scoping review is to determine what is known about abnormalities in placentas delivered from GDM pregnancies, and how early in gestation these abnormalities arise. A secondary goal is to review to what extent other selected factors, in particular obesity, have been found to influence or modify the reported effects of GDM on placental development, and whether these are considered in the study of GDM placentas. PubMed and Scopus databases were searched using the key terms: "gestational diabetes AND (woman OR human) AND placenta AND (ultrasound OR ultrastructure OR imaging OR histology OR pathology). Studies of gross morphology and histoarchitecture in placentas delivered from GDM pregnancies consistently report increased placental size, villous immaturity and a range of vascular lesions when compared to uncomplicated pregnancies. In contrast, a small number of ultrasound studies have examined placental development in GDM pregnancies in the second, and especially, the first trimester. Relatively few studies have analyzed interactions with maternal BMI, but these do suggest that it may play a role in placental abnormalities. Further examination of placental development early in pregnancy is needed to understand when it becomes disrupted in GDM, as a first step to identifying the underlying causes.

Transcriptional profiling reveals altered biological characteristics of chorionic stem cells from women with gestational diabetes

Background

Gestational diabetes (GDM) is a common complication of pregnancy. The impact of pregnancy complications on placental function suggests that extraembryonic stem cells in the placenta may also be affected during pregnancy. Neonatal tissue-derived stem cells, with the advantages of their differentiation capacity and non-invasive isolation processes, have been proposed as a promising therapeutic avenue for GDM management through potential cell therapy approaches. However, the influence of GDM on autologous stem cells remains unclear. Thus, studies that provide comprehensive understanding of stem cells isolated from women with GDM are essential to guide future clinical applications.

Methods

Human chorionic membrane-derived stem cells (CMSCs) were isolated from placentas of healthy and GDM pregnancies. Transcriptional profiling was performed by DNA microarray, and differentially regulated genes between GDM- and Healthy-CMSCs were used to analyse molecular functions, differentiation, and pathway enrichment. Altered genes and biological functions were validated via real-time PCR and in vitro assays.

Results

GDM-CMSCs displayed, vs. Healthy-CMSCs, 162 upregulated genes associated with increased migration ability, epithelial development, and growth factor-associated signal transduction while the 269 downregulated genes were strongly linked to angiogenesis and cellular metabolic processes. Notably, significantly reduced expression of detoxification enzymes belonging to the aldehyde dehydrogenase gene families (ALDH1A1/1A2, ALDH2, ALDH3) accounted for downregulation across several metabolic pathways. ALDH activity and inhibitor assays indicated that reduced gene expression of ALDHs affected ALDH enzymatic functions and resulted in oxidative stress dysregulation in GDM-CMSCs.

Conclusion

Our combined transcriptional analysis and in vitro functional characterisation have provided novel insights into fundamental biological differences in GDM- and Healthy-CMSCs. Enhanced mobility of GDM-CMSCs may promote MSC migration toward injured sites; however, impaired cellular metabolic activity may negatively affect any perceived benefit.