Histidine-rich glycoprotein derived peptides affect endometrial angiogenesisin vitrobut has no effect on embryo development

Effects of HRG and TP73 gene variations on ovarian response

AIMS

This study aims to investigate whether HRG gene C633T rs9898 and TP73 gene rs4648551 A > G polymorphisms have an effect on ovulation and response to the gonadotropin treatments.

MATERIALS AND METHODS

Blood samples were received from a total of 206 individuals (116 patients from whom good quality and optimal of numbers oocytes have not been able to be obtained at the IVF Center of Ondokuz Mayıs University, Faculty of Medicine and 90 controls). Genomic DNA was extracted by DNA isolation and SNP genotyping was performed by real-time qPCR method.

RESULTS

According to the results, a significant difference was observed between the patient and control groups in terms of the TP73 gene variant, however there was no significant difference regarding HRG gene polymorphism.

CONCLUSIONS

Our findings suggest that while AG genotype for TP73 could be a genetic marker for ovarian response, HRG gene C633T variation is not associated with ovarian response in our cohort. Further studies with larger study groups are required to investigate possible associations of these gene variants with ovarian response.

PlGF Immunological Impact during Pregnancy

During pregnancy, the mother’s immune system has to tolerate the persistence of paternal alloantigens without affecting the anti-infectious immune response. Consequently, several mechanisms aimed at preventing allograft rejection, occur during a pregnancy. In fact, the early stages of pregnancy are characterized by the correct balance between inflammation and immune tolerance, in which proinflammatory cytokines contribute to both the remodeling of tissues and to neo-angiogenesis, thus, favoring the correct embryo implantation. In addition to the creation of a microenvironment able to support both immunological privilege and angiogenesis, the trophoblast invades normal tissues by sharing the same behavior of invasive tumors. Next, the activation of an immunosuppressive phase, characterized by an increase in the number of regulatory T (Treg) cells prevents excessive inflammation and avoids fetal immuno-mediated rejection. When these changes do not occur or occur incompletely, early pregnancy failure follows. All these events are characterized by an increase in different growth factors and cytokines, among which one of the most important is the angiogenic growth factor, namely placental growth factor (PlGF). PlGF is initially isolated from the human placenta. It is upregulated during both pregnancy and inflammation. In this review, we summarize current knowledge on the immunomodulatory effects of PlGF during pregnancy, warranting that both innate and adaptive immune cells properly support the early events of implantation and placental development. Furthermore, we highlight how an alteration of the immune response, associated with PlGF imbalance, can induce a hypertensive state and lead to the pre-eclampsia (PE).

Levels of caspase-3 and histidine-rich glycoprotein in the embryo secretome as biomarkers of good-quality day-2 embryos and high-quality blastocysts

Morphological assessment at defined developmental stages is the most important method to select viable embryos for transfer and cryopreservation. Timing of different developmental stages in embryo development has been shown to correlate with its potential to develop into a blastocyst. However, improvements in pregnancy rates by using time-lapse techniques have been difficult to validate scientifically. Therefore, there is a need for new methods, preferably non-invasive methods based on metabolomics, genomics and proteomics, to improve the evaluation of embryo quality even further. The aim of this study was to investigate if different levels of caspase-3 and histidine-rich glycoprotein (HRG), secreted by the embryo into the culture media, can be used as biomarkers of embryo quality. In this study, a total of 334 samples of culture media were collected from in vitro fertilization (IVF) treatments at three different clinics. Protein analysis of the culture media was performed using multiplex proximity extension protein analysis to detect levels of caspase-3 and HRG in the embryo secretome. Protein levels were compared in secretome samples from high- and low-quality blastocysts and embryos that became arrested during development. Correlation between protein levels and time to morula formation was also analyzed. Furthermore, protein levels in secretomes from day-2 cultured embryos were compared on the basis of whether or not pregnancy was achieved. The results showed that caspase-3 levels were lower in secretomes from high-quality vs. low-quality blastocysts and those that became arrested (p ≤ 0.05 for both). In addition, higher HRG levels correlated with a shorter time to morula formation (p ≤ 0.001). Caspase-3 levels were also lower in secretomes from day-2 cultured embryos resulting in a pregnancy vs. those that did not (p ≤ 0.05). Furthermore, it was shown that caspase-3 might be used as a marker for predicting potential success rate after transfer of day-2 cultured embryos, where a caspase-3 cutoff level of 0.02 gave a prediction probability of 68% (p = 0.038). In conclusion, in future prediction models, levels of caspase-3 and HRG might be used as potential markers of embryo quality, and secreted caspase-3 levels could to some extent predict the outcome after transfer of day-2 cultured embryos.

Wenshen Yangxue decoction improves endometrial receptivity recovery and promotes endometrial angiogenesis in a rat model

CONTEXT

Wenshen Yangxue decoction (WSYXD) is a famous traditional Chinese medicine (TCM) formula and has been used in infertility treatment, but the exact mechanism is still unknown.

OBJECTIVES

To determine if WSYXD improves endometrial receptivity recovery and promotes endometrial angiogenesis in a rat model.

MATERIALS AND METHODS

A total of 100 proestrus female SPF Wistar rats were randomly assigned into five groups: control (saline), model (saline and hydroxyurea solution), high (5.2/100 g), middle (2.6/100 g) and low (1.3/100 g) WSYXD dose groups for 10 d. The microvessel densities, endometrial microstructure, as well as blastocysts number, were observed, followed by detection of angiogenesis-related gene/protein expression by immunohistochemistry, western blot and quantitative real-time polymerase chain reaction (RT-PCR), respectively.

RESULTS

Compared with the model group, the blastocyst number in WSYXD middle and high groups were significantly increased (4.50 ± 3.11 vs. 13.00 ± 2.12, 14.00 ± 1.83, p < 0.01). Lower MVD can be found in the model group (4.7) when compared with the normal control (13.7), middle (8.4) and high (9.7) dose groups. Additionally, significant differences were observed in VEGF, HIF-1α, p-AKT, p-PI3K, Ang1 and Ang2 (all p < 0.01) among different groups.

DISCUSSION AND CONCLUSIONS

In conclusion, WSYXD could help endometrial receptivity recovery and promote endometrial angiogenesis through PI3K, HIF-1α signalling and VEGF expression regulation. This study provides molecular evidence for application of WSYXD in the clinic and promotes new drug development from TCM.

HRG C633T polymorphism and risk of gestational hypertensive disorders: a pilot study

Background

Preeclampsia and gestational hypertensive disorders are thought to occur due to endothelial cell dysfunction and abnormal placentation, triggered by angiogenesis-related factors yet undetermined. The aim of this study was to investigate whether a genetic polymorphism (SNP) of Histidine-rich glycoprotein (HRG), HRG C633T SNP, is associated with gestational hypertensive disorders.

Methods

It was performed a nested case-control study from the BASIC Cohort of Uppsala University Hospital comprising 92 women diagnosed with gestational hypertensive disorders without other comorbidities and 200 women with full term uncomplicated pregnancies, all genotyped regarding HRG C633T SNP.

Results

The genetic analysis of the study sample showed that C/C genotype was more prevalent among controls. The presence of the T-allele showed a tendency towards an increased risk of gestational hypertensive disorders. After clustering the study participants based on their genotype, it was observed that the odds for gestational hypertensive disorders among heterozygous C/T or homozygous T/T carriers were higher compared to homozygous C/C carriers [OR 1.72, 95% CI (1.04–2.84)]. The association remained significant even after adjustment for maternal age, BMI and parity.

Conclusions

The HRG C633T genotype seems to be associated with gestational hypertensive disorders, and as part of a greater algorithm, might contribute in the future to the prediction of the individual susceptibility to the condition.