ORCID Profile
0000-0002-2916-1428
Current Organisations
University of the Punjab
,
Thermo Fisher Scientific/ Patheon Biologics
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Publisher: Elsevier BV
Date: 08-2019
Publisher: Springer Science and Business Media LLC
Date: 06-01-2021
DOI: 10.1007/S43032-020-00413-1
Abstract: Maternal alcohol consumption during pregnancy results in elevated vulnerability to intrauterine growth restriction, preterm birth, miscarriage, and stillbirth. Many of the detrimental effects of fetal alcohol exposure may be mediated through placental dysfunction however, the exact mechanisms remain unknown. Here, we aimed to determine the effect of maternal alcohol exposure prior to and during early pregnancy on placental glucocorticoid receptor (GR) isoforms, associated GR regulated genes, and infant outcomes. Participants carrying singleton fetuses (n = 113) were recruited during early pregnancy. Amount and type of alcohol consumed over the last 12 months were obtained at 18 weeks of gestation. The level of drinking was separated into none (0 g/day), low ( 100 g/day). At delivery, placental weight, infant sex, birthweight, and head circumference were recorded. Placental GR isoforms and genes involved in downstream signalling pathways were quantified. The majority of women (70.8%) consumed alcohol. Of these, most consumed low (48.8%) or moderate (37.5%) amounts. Placental weight was unaffected by alcohol consumption, but infants born to heavy drinkers tended to be lighter at birth. In female, but not male, placentae, maternal alcohol consumption resulted in increased GRαC and decreased GRαD1 cytoplasmic expression. In both female and male placentae, a d ened inflammatory response was evident with maternal alcohol consumption, involving downregulated IL6R and upregulated POU2F2 gene expression, respectively. Maternal alcohol consumption in the months prior to, and/or during early, pregnancy alters placental GR isoform and expression of some inflammatory genes in a sex-specific manner.
Publisher: Elsevier BV
Date: 03-2022
DOI: 10.1016/J.PLACENTA.2022.02.010
Abstract: The mechanisms that contribute to continued male intrauterine growth in response to an adverse maternal environment, such as those brought on by maternal asthma, remain largely undefined but may, in part, be mediated by androgen-mediated signalling. We previously reported the expression of multiple AR protein isoforms in the human placenta and proposed the novel AR-45 isoform to be integral in mediating male-specific androgen-dependent signalling in the presence of maternal asthma. In the current study we have used an ex vivo approach to further understand sex-specific differences in placental androgen signalling in the presence and absence of inflammation using human term villous placental explants. Explants were cultured in the presence and absence of 0.1 nM dihydrotestosterone (DHT), 1 μg/ml lipopolysaccharide (LPS), or DHT + LPS for 24hr. Tissue was used for gene expression and subcellular AR protein isoform expression. Cytoplasmic and nuclear AR protein isoforms expression did not vary between culture conditions in either sex. AR-45 activity was upregulated in male placentae cultured in DHT, LPS and DHT + LPS only. There were no changes in the expression of androgen-mediated downstream targets in males in response to culture conditions, but females had significantly reduced IGF1R expression in response to LPS. Increased AR-45 activity in the presence of inflammation may drive continued male feto-placental growth via maintained expression of downstream growth targets. Our findings build on previous work suggesting an important role for AR-45 in regulating male-specific adaptations to placental inflammation and underscores the need to further characterise the function of this AR isoform.
Publisher: ClinMed International Library
Date: 31-12-2015
Publisher: Informa UK Limited
Date: 25-10-2023
DOI: 10.1080/02770903.2022.2134794
Abstract: Asthma and obesity are both inflammatory complications of pregnancy and when combined contribute to an increased risk of uncontrolled asthma during pregnancy and poor perinatal outcomes. Our previous work has identified the presence of maternal asthma is associated with a proinflammatory milieu in the placenta and reduced fetal growth. The current study was designed to determine the relationships between immunomodulatory metabolic pathways and inflammation and establish whether these pathways are associated with uncontrolled asthma in obese pregnant women. Fifty-three obese (BMI >30) pregnant women were recruited prospectively. Participants were classified as having no asthma, controlled asthma, and uncontrolled asthma based on a doctor diagnosis and assessment using the Asthma Control Questionnaire (ACQ). Circulating plasma concentrations of metabolic hormones leptin, adiponectin, insulin, glucose, and extracellular vesicle (EVs) associated cytokines were measured at 18- and 36-weeks gestation. Concentrations of metabolic and inflammatory markers among obese participants with or without asthma were not significantly different throughout gestation. However total adiponectin concentrations increased as gestation progressed in obese, non-asthmatic women but did not increase in women with asthma. Plasma adiponectin and leptin levels in women with uncontrolled asthma were positively correlated with EV inflammatory markers including GM-CSF, IL-6, TNFα and IFNγ protein. This study demonstrated that most metabolic markers remain unchanged with the presence and severity of asthma in obese pregnant women. However, differences in the associations between metabolic and inflammatory pathways were observed in women with asthma and may be one of the mechanisms contributing to uncontrolled asthma in obese pregnant women.
Publisher: Bioscientifica
Date: 08-2017
DOI: 10.1530/JOE-17-0171
Abstract: Maternal dexamethasone exposure in the mouse impairs placental development and programs adult disease in a sexually dimorphic manner. Glucocorticoids bind to different glucocorticoid receptor (GR) isoforms to regulate gene transcription and cellular signaling. We hypothesized that sexually dimorphic placental responses to glucocorticoids are due to differences in GR isoforms present in the placenta. Pregnant C57Bl6 mice were exposed to saline or dexamethasone from E12.5 until E14.5 (1 µg/kg/h) before the collection of placentae. Cytoplasmic and nuclear protein fractions were extracted from placentae of male and female fetuses for Western blot analysis of GR isoforms. Eight known isoforms of the GR were detected in the mouse placenta including the translational isoforms GRα-A, B, C and D1–3 and the splice variants GRA and GRP. The expression of GRA, GRP and each of the GRα isoforms were altered by dexamethasone in relation to fetal sex and cellular location. Placentae of female fetuses had higher GRα-A and GRP expression in the cytoplasm than males, and GRα-C was more highly expressed in the nucleus of females than that in males. Dexamethasone significantly increased the cytoplasmic expression of GRα-A, but reduced the expression of GRα-C in placentae of males. Dexamethasone increased the expression of the GRα-C-regulated genes Sgk1 and Bcl2l11 , particularly in females. The cleaved caspase-3 staining in placental sections indicated GRα-C may mediate sex differences in dexamethasone-induced apoptosis. These findings may underlie the sex-specific placental adaptations that regulate different growth profiles in males and females and different risks for programmed disease outcomes in offspring.
Publisher: Elsevier BV
Date: 06-2017
DOI: 10.1016/J.PLACENTA.2016.12.017
Abstract: The physiological mechanisms that confer different outcomes in morbidity and mortality of the fetus exposed to stressful environments may be driven by significant differences in the expression and function of the placental glucocorticoid receptor (GR). The recent discovery that the placenta contains at least 8 different isoforms of the GR raises questions about the regulation and physiological relevance of the many GR variants expressed in the placenta. The current data also highlights that in idual differences in glucocorticoid sensitivity, variations in the effect of different complications of pregnancy on birth outcomes and sex differences in the response to stress, may all be dependent on a specific GR isoform expression profile. This review will investigate the current state of knowledge of GR isoforms in the placenta and discuss the potential role of these multiple isoforms in regulating glucocorticoid sensitivity.
Publisher: Elsevier BV
Date: 09-2018
Publisher: American Association for Cancer Research (AACR)
Date: 15-12-2005
DOI: 10.1158/0008-5472.CAN-05-0936
Abstract: A BAC located in the 16q24.3 breast cancer loss of heterozygosity region was previously shown to restore cellular senescence when transferred into breast tumor cell lines. We have shown that FBXO31, although located just distal to this BAC, can induce cellular senescence in the breast cancer cell line MCF-7 and is the likely candidate senescence gene. FBXO31 has properties consistent with a tumor suppressor, because ectopic expression of FBXO31 in two breast cancer cell lines inhibited colony growth on plastic and inhibited cell proliferation in the MCF-7 cell line. In addition, compared with the relative expression in normal breast, levels of FBXO31 were down-regulated in breast tumor cell lines and primary tumors. FBXO31 was cell cycle regulated in the breast cell lines MCF-10A and SKBR3 with maximal expression from late G2 to early G1 phase. Ectopic expression of FBXO31 in the breast cancer cell line MDA-MB-468 resulted in the accumulation of cells at the G1 phase of the cell cycle. FBXO31 contains an F-box domain and is associated with the proteins Skp1, Roc-1, and Cullin-1, suggesting that FBXO31 is a component of a SCF ubiquitination complex. We propose that FBXO31 functions as a tumor suppressor by generating SCFFBXO31 complexes that target particular substrates, critical for the normal execution of the cell cycle, for ubiquitination and subsequent degradation. (Cancer Res 2005 65(24): 11304-313)
Publisher: Public Library of Science (PLoS)
Date: 03-02-2016
Publisher: Elsevier BV
Date: 09-2017
Publisher: Elsevier BV
Date: 11
DOI: 10.1016/J.PLACENTA.2021.01.003
Abstract: Maternal asthma is known to impact intrauterine growth outcomes, which may be mediated, in part, by altered androgen signalling. Our aim was to explore whether the sheep placenta expresses androgen receptor (AR) isoforms and determine if the differential expression of AR protein isoforms is altered by maternal asthma. Four known AR isoforms were detected (AR-FL, AR-v1, AR-v7, and AR-45), and their expression and subcellular distribution was altered in the presence of maternal allergic asthma. These findings underscore the importance for in vivo models of maternal asthma to delineate molecular patterns that may contribute to feto-placental growth and development.
Publisher: Future Medicine Ltd
Date: 2012
DOI: 10.2217/EBO.11.61
Publisher: Elsevier BV
Date: 05-2021
DOI: 10.1016/J.PLACENTA.2021.03.013
Abstract: The human placenta expresses multiple glucocorticoid receptor (GR) isoforms that may be partially regulated by the untranslated 5' exon 1 GR gene promoter region which consists of 9 different promoters and 13 splice variants. The objective of this study was to determine which GR exon 1 variants are expressed in the human placenta and relate these findings to GR mRNA and protein expression. Placental extracts from pregnancies with or without the complication of maternal asthma and trophoblast cells exposed to an inflammatory challenge in vitro were examined using PCR and Western blot to measure GR exon 1 variants, GR splice variant mRNA and GR protein isoforms, respectively. All 9 GR exon 1 variants were detectable in the human placenta and included GR exons 1A, 1B, 1C, 1D, 1E, 1F, 1H, 1I and 1J. In the presence of maternal asthma and a male fetus there was preferential expression of GR exon 1B, 1C, IF and 1J (KW-ANOVA, P < 0.05) which were positively correlated with GRα D3 protein isoform. In female placentae from pregnancies complicated by asthma there was no upregulation of any exon 1 variant (KW-ANOVA, P < 0.05). Exposure of BeWo trophoblast cell line to an inflammatory challenge, lipopolysaccharide, in vitro, resulted in preferential expression of GR exon 1B, 1D, 1E and 1H and associated with GRα-D1 protein upregulation. The preferential expression of different GR exon 1 promoters drive the upregulation of GRα D isoforms and contribute to glucocorticoid resistance observed in male placentae of pregnancies complicated by asthma.
Publisher: Elsevier BV
Date: 06-2017
DOI: 10.1016/J.PLACENTA.2017.01.123
Abstract: Asthma is a highly prevalent chronic medical condition affecting an estimated 12% of pregnant, women each year, with prevalence of asthma greatest (up to 16%) among the socially disadvantaged. Maternal asthma is associated with significant perinatal morbidity and mortality including preterm births, neonatal hospitalisations and low birthweight outcomes each year. We have identified that the placenta adapts to the presence of chronic, maternal asthma during pregnancy in a sex specific manner that may confer sex differences in fetal outcome. The male fetus was at greater risk of a poor outcome than a female fetus in the presence of maternal asthma and an acute inflammatory event such as an asthma exacerbation. This review will examine the role of sex specific differences in placental function on fetal growth and survival.
Publisher: Elsevier BV
Date: 05-2019
DOI: 10.1016/J.PLACENTA.2019.03.012
Abstract: Numerous studies show that males have increased intrauterine growth compared to females, and that pregnancy complications may further these growth differences, but the regulatory mechanisms underlying these differences remain unknown. We propose that these growth outcomes may be due to sex-specific differences in androgen sensitivity - giving rise to altered growth signalling pathways - mediated by the differential expression of placental androgen receptor (AR) variants. Placental protein and mRNA were used to identify AR protein variant levels and AR-downstream target gene expression, and were then analysed against neonatal measurements. Dihydrotestosterone (DHT)-induced AR protein variant expression and downstream growth factors were examined in vitro. Four known AR variants (AR-FL, AR-V1, AR-V7, and AR-45), and three unknown proteins (120, 90 and 55 kDa) immunoreactive to the anti-AR antibody were identified in human placentae. Male placentae from controlled asthmatic pregnancies had increased AR-45 and decreased AR-V1 and AR-V7 nuclear expression. Increased nuclear AR-45 expression was associated with increased insulin-like growth factor 1 (IGF-1), IGF-1 receptor (IGF-1R), and IGF-binding protein 5 (IGFBP-5) mRNA expression and normal male growth. AR-45 mRNA and protein did not change in the presence of uncontrolled maternal asthma and associated with an increase in small for gestational (SGA) male fetuses. In vitro DHT stimulation increased AR-45 protein and IGF-1R and IGFBP-5 mRNA expression. Collectively, our data shows altered AR protein expression and downstream signalling targets may contribute to sex-specific fetal growth outcomes in response to an adverse environment, and that AR-45 appears central in mediating these changes.
Publisher: Elsevier BV
Date: 04-2014
DOI: 10.1016/J.PLACENTA.2014.01.012
Abstract: We have previously identified sex-specific differences in the fetal-placental response to cortisol. Our recent studies suggest that this differential response to cortisol is driven by differences in glucocorticoid receptor (GR) protein function rather than through changes in gene transcription or protein expression. This study was designed to define whether the human placenta expresses different isoforms of the GR and whether expression was altered by fetal sex and maternal asthma. Asthma and non-asthma pregnant women were prospectively recruited at their first antenatal visit and placentae collected at delivery. Placental GR expression was examined in relation to maternal asthma, fetal sex and birthweight. Twelve specific bands for the GR were identified at molecular weights of 94, 91, 81, 74, 69, 68, 65, 60, 55, 50, 48 and 38 kDa. The 12 isoforms were localised to the placental trophoblast and expression varied in relation to cellular location in either the cytoplasm or nucleus, fetal sex, fetal size and the presence and absence of maternal asthma. This is the first study to identify the presence of several protein isoforms of the GR in the human placenta. The data suggest glucocorticoid resistance observed in male placentae may be mediated through increased GRβ, GR A and GR P localisation to the nucleus. While female placentae may be more sensitive to cortisol in the presence of maternal asthma through a decrease in GRβ and an enhancement GRα activity via an interaction with GRα D3 and GRα C.
Publisher: Elsevier BV
Date: 09-2017
Publisher: Elsevier BV
Date: 07-2015
Location: Australia
Location: Pakistan
No related grants have been discovered for Zarqa Saif.