Obstetrics and Gynaecology - Research Publications

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    Punicalagin Suppresses Mediators Involved in Labor Onset and Progression in vitro
    Nguyen-Ngo, C ; Willcox, JC ; Lappas, M (Science Publications, 2021-01-01)
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    Extracellular vesicles and their potential role inducing changes in maternal insulin sensitivity during gestational diabetes mellitus
    Nair, S ; Ormazabal, V ; Lappas, M ; McIntyre, HD ; Salomon, C (WILEY, 2021-02)
    Gestational diabetes mellitus (GDM) is one of the most common endocrine disorders during gestation and affects around 15% of all pregnancies worldwide, paralleling the global increase in obesity and type 2 diabetes. Normal pregnancies are critically dependent on the development of maternal insulin resistance balanced by an increased capacity to secrete insulin, which allows for the allocation of nutrients for adequate foetal growth and development. Several factors including placental hormones, inflammatory mediators and nutrients have been proposed to alter insulin sensitivity and insulin response and underpin the pathological outcomes of GDM. However, other factors may also be involved in the regulation of maternal metabolism and a complete understanding of GDM pathophysiology requires the identification of these factors, and the mechanisms associated with them. Recent studies highlight the potential utility of tissue-specific extracellular vesicles (EVs) in the diagnosis of disease onset and treatment monitoring for several pregnancy-related complications, including GDM. To date, there is a paucity of data defining changes in the release, content, bioactivity and diagnostic utility of circulating EVs in pregnancies complicated by GDM. Placental EVs may engage in paracellular interactions including local cell-to-cell communication between the cell constituents of the placenta and contiguous maternal tissues, and/or distal interactions involving the release of placental EVs into biological fluids and their transport to a remote site of action. Hence, the aim of this review is to discuss the biogenesis, isolation methods and role of EVs in the physiopathology of GDM, including changes in maternal insulin sensitivity during pregnancy.
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    Obstetric and perinatal outcomes for women with pre-existing diabetes in rural compared to metropolitan settings in Victoria, Australia
    Williamson, RL ; McCarthy, EA ; Oats, JJ ; Churilov, L ; Lappas, M ; Shub, A (WILEY, 2021-06)
    BACKGROUND: Pre-existing diabetes in pregnancy is associated with an increased risk of complications. Likewise, living in rural, regional and remote Victoria, Australia, is also associated with poorer health outcomes. There is a gap in the literature with regard to whether Victorian women with pre-existing diabetes experience a greater risk of adverse pregnancy outcomes compared to their metropolitan counterparts. AIM: Our objective is to compare obstetric and perinatal outcomes for women with pre-existing diabetes delivering in rural vs metropolitan hospitals in Victoria, Australia. MATERIALS AND METHODS: Retrospective population-based study using routinely collected state-based data of singleton births to women with type 1 and type 2 diabetes who delivered in metropolitan (n = 3233) and rural hospitals (n = 693) in Victoria, Australia, between 2006-2015. Pearson's χ2 test, Fisher's exact test and MannWhitney U-test were used to compare obstetric and perinatal outcomes between metropolitan and rural locations. RESULTS: Delivery in a rural hospital was associated with higher rates of stillbirth (2.3% vs 1.1%, P = 0.027), macrosomia (25.9% vs 16.9%, P < 0.001), shoulder dystocia (8.4% vs 3.5%, P < 0.001) and admission to the neonatal intensive care unit/special care nursery (73.2% vs 59.3%, P < 0.001). Smoking (18.0% vs 8.9%, P < 0.001), overweight/obesity (P = 0.047) and socioeconomic disadvantage (P < 0.001) were more common in rural women. CONCLUSIONS: Women with pre-existing diabetes who deliver in rural hospitals experience a greater risk of adverse perinatal outcomes and present with increased maternal risk factors. These results suggest a need to improve care for women with pre-existing diabetes in rural Victoria.
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    Hepatitis A virus cellular receptor 2 (HAVCR2) is decreased with viral infection and regulates pro-labour mediators OA
    Liong, S ; Lim, R ; Barker, G ; Lappas, M (WILEY, 2017-07)
    PROBLEM: Intrauterine infection caused by viral infection has been implicated to contribute to preterm birth. Hepatitis A virus cellular receptor 2 (HAVCR2) regulates inflammation in non-gestational tissues in response to viral infection. METHOD OF STUDY: The aims of this study were to determine the effect of: (i) viral dsRNA analogue polyinosinic:polycytidylic acid (poly(I:C)) on HAVCR2 expression; and (ii) HAVCR2 silencing by siRNA (siHAVCR2) in primary amnion and myometrial cells on poly(I:C)-induced inflammation. RESULTS: In human foetal membranes and myometrium, HAVCR2 mRNA and protein expression was decreased when exposed to poly(I:C). Treatment of primary amnion and myometrial cells with poly(I:C) significantly increased the expression and release of pro-inflammatory cytokines TNF, IL1A, IL1B and IL6; the expression of chemokines CXCL8 and CCL2; the expression and secretion of adhesion molecules ICAM1 and VCAM1; and PTGS2 and PTGFR mRNA expression and the release of prostaglandin PGF2α . This increase was significantly augmented in cells transfected with siHAVCR2. Furthermore, mRNA expression of anti-inflammatory cytokines IL4 and IL10 was significantly decreased. CONCLUSION: Collectively, our data suggest that HAVCR2 regulates cytokines, chemokines, prostaglandins and cell adhesion molecules in the presence of viral infection. This suggests a potential for HAVCR2 activators as therapeutics for the management of preterm birth associated with viral infections.
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    TRADD, TRAF2, RIP1 and TAK1 are required for TNF--induced pro-labour mediators in human primary myometrial cells
    Lim, R ; Barker, G ; Lappas, M (WILEY, 2017-07)
    PROBLEM: TNF-α plays a central role in the processes of human labour and delivery. This study sought to determine the role of the adaptor proteins TNFR1-associated death domain protein (TRADD), TNF receptor-associated factor 2 (TRAF2), receptor interacting protein 1 (RIP1) and transforming growth factor beta-activated kinase 1 (TAK1) in TNF-α-induced formation of pro-labour mediators. METHOD OF STUDY: Human primary myometrial cells were transfected with siRNA against TRADD (siTRADD), TRAF2 (siTRAF2), RIP1 (siRIP1) or TAK1 (siTAK1), treated with TNF-α, and assayed for pro-inflammatory mediators expression. RESULTS: siTRADD, siTRAF2, siRIP1 and siTAK1 significantly decreased TNF-α-induced IL-1α, IL-1β, IL-6, IL-8, MCP-1 mRNA expression and release of IL-6, IL-8 and MCP-1; and cyclooxygenase (COX)-2 expression and release of prostaglandin PGF2α . There was a significant attenuation of TNF-α-induced expression of adhesion molecules ICAM-1 and VCAM-1 mRNA with siTRADD, siTRAF2 or siRIP1. siTRADD and siRIP1 significantly attenuated TNF-α-induced MMP-9 mRNA expression and release and nuclear factor κB (NF-κB) transcriptional activity. There was a significant increase in TNF-α-induced sVCAM-1 release, MMP-9 mRNA expression and NF-κB activity with siTAK1. CONCLUSION: TRADD, TRAF2, RIP1 and TAK1 are involved in TNF-α signalling in human myometrium. Further studies are required to determine whether inhibition of these proteins can prevent preterm birth.
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    A mobile health intervention promoting healthy gestational weight gain for women entering pregnancy at a high body mass index: the txt4two pilot randomised controlled trial
    Willcox, JC ; Wilkinson, SA ; Lappas, M ; Ball, K ; Crawford, D ; McCarthy, EA ; Fjeldsoe, B ; Whittaker, R ; Maddison, R ; Campbell, KJ (WILEY, 2017-10)
    OBJECTIVE: To determine the feasibility and effectiveness of an mHealth intervention promoting healthy diet, physical activity and gestational weight gain in pregnant women. DESIGN: Randomised controlled trial (RCT). SETTING: Australian tertiary obstetric hospital. POPULATION: One hundred pregnant women who were overweight or obese prior to pregnancy. METHODS: Women recruited at the first antenatal clinic visit were randomised to either an intervention or a control group. The intervention consisted of a tailored suite of strategies delivered (from first antenatal visit until 36 weeks' gestation) via multiple modalities available on mobile devices. MAIN OUTCOME MEASURES: The primary outcome was intervention feasibility and secondary outcomes were objectively measured changes in gestational weight gain (GWG) and self-reported dietary intake and physical activity. RESULTS: Ninety-one women completed the study. Delivery to protocol provides evidence of program feasibility. Most women engaged regularly with the program, with the majority (97.6%) reporting that the intervention was helpful. Secondary outcomes demonstrated a significantly lower GWG in the intervention group (7.8 kg ± 4.7 versus 9.7 kg ± 3.9; P =0.041) compared with the control group at intervention completion. Intervention group women reported significantly smaller reductions in total, light- and moderate-intensity physical activity from baseline to completion of the intervention (P = 0.001) compared with the control group, but no differences in consumption frequencies of key food groups. CONCLUSION: An intervention that aimed to deliver healthy diet, physical activity and GWG guidance utilising innovative technology can be feasibly implemented and produce positive physical activity and GWG outcomes. TWEETABLE ABSTRACT: txt4two mHealth study improved gestational weight gain and physical activity in pregnant women with high BMIs.
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    Maternal 25-hydroxyvitamin D is inversely correlated with foetal serotonin
    Murthi, P ; Davies-Tuck, M ; Lappas, M ; Singh, H ; Mockler, J ; Rahman, R ; Lim, R ; Leaw, B ; Doery, J ; Wallace, EM ; Ebeling, PR (WILEY, 2017-03)
    OBJECTIVE: Maternal vitamin D deficiency during pregnancy has been linked to impaired neurocognitive development in childhood. The mechanism by which vitamin D affects childhood neurocognition is unclear but may be via interactions with serotonin, a neurotransmitter involved in foetal brain development. In this study, we aimed to explore associations between maternal and foetal vitamin D concentrations, and foetal serotonin concentrations at term. STUDY DESIGN AND MEASUREMENTS: Serum 25-hydroxyvitamin D (25(OH)D, nmol/l) and serotonin (5-HT, nmol/l) concentrations were measured in maternal and umbilical cord blood from mother-infant pairs (n = 64). Association between maternal 25(OH)D, cord 25(OH)D and cord serotonin was explored using linear regression, before and after adjusting for maternal serotonin levels. We also assessed the effects of siRNA knockdown of the vitamin D receptor (VDR) and administration of 10 nm 1,25-dihydroxyvitamin D3 on serotonin secretion in human umbilical vein endothelial cells (HUVECs) in vitro. RESULTS: We observed an inverse relationship between both maternal and cord 25(OH)D concentrations with cord serotonin concentrations. The treatment of HUVECs with 1,25-dihydroxyvitamin D3 in vitro decreased the release of serotonin (193·9 ±14·8 nmol/l vs 458·9 ± 317·5 nmol/l, control, P < 0·05). Conversely, inactivation of VDR increased serotonin release in cultured HUVECs. CONCLUSIONS: These observations provide the first evidence of an inverse relationship between maternal 25(OH)D and foetal serotonin concentrations. We propose that maternal vitamin D deficiency increases foetal serotonin concentrations and thereby contributes to longer-term neurocognitive impairment in infants and children.
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    Extracellular vesicle-associated miRNAs are an adaptive response to gestational diabetes mellitus
    Nair, S ; Guanzon, D ; Jayabalan, N ; Lai, A ; Scholz-Romero, K ; de Croft, PK ; Ormazabal, V ; Palma, C ; Diaz, E ; McCarthy, EA ; Shub, A ; Miranda, J ; Gratacos, E ; Crispi, F ; Duncombe, G ; Lappas, M ; McIntyre, HD ; Rice, G ; Salomon, C (BMC, 2021-08-20)
    BACKGROUND: Gestational diabetes mellitus (GDM) is a serious public health issue affecting 9-15% of all pregnancies worldwide. Recently, it has been suggested that extracellular vesicles (EVs) play a role throughout gestation, including mediating a placental response to hyperglycaemia. Here, we investigated the EV-associated miRNA profile across gestation in GDM, assessed their utility in developing accurate, multivariate classification models, and determined the signaling pathways in skeletal muscle proteome associated with the changes in the EV miRNA profile. METHODS: Discovery: A retrospective, case-control study design was used to identify EV-associated miRNAs that vary across pregnancy and clinical status (i.e. GDM or Normal Glucose Tolerance, NGT). EVs were isolated from maternal plasma obtained at early, mid and late gestation (n = 29) and small RNA sequencing was performed. Validation: A longitudinal study design was used to quantify expression of selected miRNAs. EV miRNAs were quantified by real-time PCR (cases = 8, control = 14, samples at three times during pregnancy) and their individual and combined classification efficiencies were evaluated. Quantitative, data-independent acquisition mass spectrometry was use to establish the protein profile in skeletal muscle biopsies from normal and GDM. RESULTS: A total of 2822 miRNAs were analyzed using a small RNA library, and a total of 563 miRNAs that significantly changed (p < 0.05) across gestation and 101 miRNAs were significantly changed between NGT and GDM. Analysis of the miRNA changes in NGT and GDM separately identified a total of 256 (NGT-group), and 302 (GDM-group) miRNAs that change across gestation. A multivariate classification model was developed, based on the quantitative expression of EV-associated miRNAs, and the accuracy to correctly assign samples was > 90%. We identified a set of proteins in skeletal muscle biopsies from women with GDM associated with JAK-STAT signaling which could be targeted by the miRNA-92a-3p within circulating EVs. Interestingly, overexpression of miRNA-92a-3p in primary skeletal muscle cells increase insulin-stimulated glucose uptake. CONCLUSIONS: During early pregnancy, differently-expressed, EV-associated miRNAs may be of clinical utility in identifying presymptomatic women who will subsequently develop GDM later in gestation. We suggest that miRNA-92a-3p within EVs might be a protected mechanism to increase skeletal muscle insulin sensitivity in GDM.
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    Anti-Diabetic, Anti-Inflammatory, and Anti-Oxidant Effects of Naringenin in an In Vitro Human Model and an In Vivo Murine Model of Gestational Diabetes Mellitus
    Nguyen-Ngo, C ; Willcox, JC ; Lappas, M (WILEY, 2019-10)
    SCOPE: Gestational diabetes mellitus (GDM), which affects up to 20% of pregnant women, is associated with maternal peripheral insulin resistance, low-grade inflammation, and oxidative stress. The flavonoid naringenin has potent anti-diabetic, anti-inflammatory, and anti-oxidative properties; however, its effects in GDM remain unknown. The study aimed to determine the effects of naringenin on glucose metabolism, inflammation, and oxidative stress associated with GDM both in vitro and in vivo. METHODS AND RESULTS: In vitro, human tissue samples obtained at term elective Caesarean section are stimulated with tumour necrosis factor alpha (TNF) to develop a GDM-like environment. Naringenin treatment significantly improves TNF-impaired glucose uptake in skeletal muscle. In placenta and visceral adipose tissue (VAT), naringenin significantly reduces expression of pro-inflammatory cytokines and chemokines and increases antioxidant mRNA expression. Mechanistically, naringenin suppresses nuclear factor κB activation. In vivo, pregnant heterozygous db/+ mice are used to model GDM. Daily intraperitoneal injections of GDM mice with naringenin from gestational day 10-17 significantly improve glucose tolerance, reduces IL1A mRNA expression, and increases antioxidant mRNA expression in placenta, VAT, and subcutaneous adipose tissue. CONCLUSION: Naringenin is shown to improve insulin sensitivity, inflammation, and oxidative stress associated with GDM and shows promise as a novel preventive therapeutic.