Searchable abstracts of presentations at key conferences in endocrinology

ea0044ec1.5 | Early Career Symposium: Launching your career whatever it may be | SFEBES2016

Rejection from Tesco: Making your PhD work

Mirczuk Samantha

We all work incredibly hard to produce a thesis that will allow us to sail through our vivas and get that piece of paper, which says we have a doctorate. The next step is to grab hold of an exciting post-doc position, where we can press the “start” button on a rather traditional career path to independence. During the course of two post-docs, the golden numbers of research articles will be written, submitted, peer-reviewed and published, allowing for a fellowship app...

ea0034p155 | Cytokines and growth factors | SFEBES2014

Modelling hepatic encephalopathy in vitro: molecular and functional consequences of hyperammonaemia in C6 glioma cells

Mirczuk Samantha , Robson Camille , Stacey Emily , Fowkes Robert , Lipscomb Victoria

Hepatic encephalopathy (HE), a syndrome of neurological abnormalities caused by impaired liver function, is induced by many chronic liver diseases, such as liver failure or hepatic portosystemic shunts. Whilst multiple substances reach toxic levels in the systemic circulation of HE patients, hyperammonemia (excessive ammonia) is known to be a major contributing factor to the neurological disturbances. Astrocytes utilise ammonia in generating glutamine leading to brain oedema a...

ea0034p163 | Growth and development | SFEBES2014

C-type natriuretic peptide regulates growth and pituitary development in the zebrafish (Danio rerio)

Lessey Andrew , Mirczuk Samantha , McGonnell Imelda , Fowkes Robert

C-type natriuretic peptide (CNP), the predominant natriuretic peptide in the pituitary, is associated with neuroendocrine development and function. Our previous studies show that genes encoding CNP (nppc2, cnp3, nppc4, and nppcl) are expressed during pituitary development in humans and zebrafish (Danio rerio), however a precise role for CNP in the pituitary has yet to be elucidated. Using the versatile zebrafish, we explored in ...

ea0031p140 | Growth and development | SFEBES2013

Comprehensive spatio-temporal expression profiling reveals a complete natriuretic peptide system in the developing Zebrafish (Danio rerio)

Lessey Andrew , Mirczuk Samantha , McGonnell Imelda , Fowkes Robert

C-type natriuretic peptide (CNP) is the ancestral and most highly conserved member of the mammalian natriuretic peptide family. Although broadly expressed throughout the periphery (bone, gonads, kidneys), CNP is the major natriuretic peptide of the brain and CNS and is suspected to influence neuroendocrine function. Our recent studies using fetal human pituitary samples has shown that the gene encoding CNP, NPPC, is expressed early on in pituitary development but a co...

ea0031p248 | Pituitary | SFEBES2013

Transcriptional regulation of C-type natriuretic peptide (CNP/Nppc) and its receptor guanylyl cyclase-B (GC-B/Npr2) in gonadotroph and somatolactotroph cell lines

Mirczuk Samantha , Jones Alexander , McGonnell Imelda , Fowkes Robert

C-type natriuretic peptide (CNP) has recently been implicated as a key meiotic arrest factor in oocytes, and mechanistic studies suggest that the transcriptional regulation of the CNP gene (Nppc) and of its receptor, GC-B (Npr2) is sensitive to gonadotrophin-dependent cAMP accumulation. We have shown CNP to be a major regulator of gonadotrophs in the pituitary, but have yet to establish how either Nppc or Npr2 are transcriptionally controlled locally. In the current study, the...

ea0038p373 | Reproduction | SFEBES2015

Identification of novel transcription factors that may regulate transcription of the equine chorionic gonadotrophin beta subunit

Read Jordan , Cabrera-Sharp Victoria , Mirczuk Samantha , Fowkes Robert , de Mestre Amanda

Equine Chorionic Gonadotrophin (eCG) is a heterodimeric glycoprotein produced by terminally differentiated, bi/multi-nucleate trophoblast cells in the placenta of horses and humans. It is responsible for the maintenance of early pregnancy via rescue of the corpus luteum and subsequently promotion of progesterone production. The beta subunit of eCG is expressed at levels ten-fold lower than that of the alpha subunit and confers the glycoproteins specificity to the placenta. Ver...

ea0034s7.2 | Natriuretic peptides: so much more than salt and water | SFEBES2014

Natriuretic peptides in pituitary development and function

Fowkes Robert , Mirczuk Samantha , Lessey Andrew , Lipscomb Victoria , Niessen Stijn , McArdle Craig , McGonnell Imelda

The cardiovascular properties of the natriuretic peptide family of hormones are well-characterised, and provide valuable prognostic indicators in the treatment of heart failure in humans and companion animals. Of the three main mammalian natriuretic peptides, C-type natriuretic peptide (CNP) remains the most enigmatic, even though CNP represents the ancestral natriuretic peptide from which Atrial- (ANP) and B-type (BNP) natriuretic peptides evolved through gene duplication. We...

ea0034p156 | Cytokines and growth factors | SFEBES2014

Spatial expression profiling reveals tissue-specific sexual dimorphism of the natriuretic peptide system in mice

Mirczuk Samantha , Robson Camille , Robinson Benjamin , Lessey Andrew , Lipscomb Victoria , McGonnell Imelda , Fowkes Robert

The mammalian natriuretic peptide family consists of three members, Atrial-, B-type, and C-type natriuretic peptides (ANP, BNP, and CNP respectively), and exert their effects on blood pressure, sodium homeostasis, growth and reproduction, via their selective guanylyl cyclase receptors, GC-A or GC-B. Previous attempts to map spatial expression profiling have generated conflicting results, due predominantly to the range of techniques employed, and the relative paucity of tools t...

ea0034p286 | Pituitary | SFEBES2014

The gonadotroph natriuretic peptide system is sensitive to pulsatile GnRH stimulation: insights into CNP/GC-B signalling in gonadotroph function

Mirczuk Samantha , Catterick Alice , Lessey Andrew , Perrett Rebecca , McArdle Craig , McGonnell Imelda , Fowkes Robert

Gonadotrophs in rats, mice and humans, express an intact natriuretic peptide system, in which C-type natriuretic peptide (CNP) is the predominant member. Despite showing an interaction between CNP and GnRH at the level of cGMP and Ca2+ signalling, the role of CNP in gonadotroph biology is poorly understood. In this study, we utilise a novel multiplex qRT-PCR assay, examining simultaneous expression of natriuretic peptide genes along with genes for gonadotroph transc...

ea0031p147 | Growth and development | SFEBES2013

Effects of the endocrine disrupting herbicide, Atrazine, on pituitary development, gene expression and signalling pathways in Zebrafish (Danio rerio) and mouse pituitary cell lines

Swain Joshua , Lessey Andrew , Mirczuk Samantha , Lambertucci-Bonnet Julien , Tucker Lisa , McGonnell Imelda , Fowkes Robert

Atrazine (ATR) is a widely used herbicide, with known effects as an endocrine disrupting chemical. Several studies have implicated ATR in causing disorders of sex development in reptiles, and chronic exposure can cause an increase incidence of intersex in fish, suggesting that the hypothalamo-pituitary–gonadal axis is a major site of ATR action. In this study, we investigated whether acute exposure (hours to days) to ATR could cause abnormalities in the development of Zeb...