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Dong Li Department of Orthopedics, The Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, Jiangsu, China

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Chenhao Cao Department of Orthopedics, The Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, Jiangsu, China

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Zhuofan Li Department of Orthopedics, The Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, Jiangsu, China

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Zhiyong Chang Department of Orthopedics, The Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, Jiangsu, China

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Ping Cai Department of Orthopedics, The Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, Jiangsu, China

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Chenxi Zhou Department of Orthopedics, The Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, Jiangsu, China

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Jun Liu Department of Orthopedics, The Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, Jiangsu, China

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Kaihua Li Department of Orthopedics, The Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, Jiangsu, China

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Bin Du Department of Orthopedics, The Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, Jiangsu, China

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Icariside II, a flavonoid glycoside, is the main component found invivo after the administration of Herba epimedii and has shown some pharmacological effects, such as prevention of osteoporosis and enhancement of immunity. Increased levels of marrow adipose tissue are associated with osteoporosis. S100 calcium-binding protein A16 (S100A16) promotes the differentiation of bone marrow mesenchymal stem cells (BMSCs) into adipocytes. This study aimed to confirm the anti-lipidogenesis effect of Icariside II in the bone marrow by inhibiting S100A16 expression. We used ovariectomy (OVX) and BMSC models. The results showed that Icariside II reduced bone marrow fat content and inhibited BMSCs adipogenic differentiation and S100A16 expression, which correlated with lipogenesis. Overexpression of S100A16 eliminated the inhibitory effect of Icariside II on lipid formation. β-catenin participated in the regulation adipogenesis mediated by Icariside II/S100A16 in the bone. In conclusion, Icariside II protects against OVX-induced bone marrow adipogenesis by downregulating S100A16, in which β-catenin might also be involved.

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Hsien-Ming Wu Department of Obstetrics and Gynecology, Chang Gung Memorial Hospital Linkou Medical Center, Chang Gung University School of Medicine, Taoyuan, Taiwan

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Liang-Hsuan Chen Department of Obstetrics and Gynecology, Chang Gung Memorial Hospital Linkou Medical Center, Chang Gung University School of Medicine, Taoyuan, Taiwan

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Wei-Jung Chiu Department of Obstetrics and Gynecology, Chang Gung Memorial Hospital Linkou Medical Center, Chang Gung University School of Medicine, Taoyuan, Taiwan

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Chia-Lung Tsai Department of Obstetrics and Gynecology, Chang Gung Memorial Hospital Linkou Medical Center, Chang Gung University School of Medicine, Taoyuan, Taiwan

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In this study, we investigate the effects of miRNA-138-5p and probable G-protein coupled receptor 124 (GPR124)-regulated inflammasome and downstream leukemia inhibitory factor (LIF)–STAT and adhesion molecule signaling in human decidual stromal cells. After informed consent was obtained from women aged 25–38 years undergoing surgical termination of the normal pregnancy and spontaneous miscarriage after 6–9 weeks of gestation, human decidual stromal cells were extracted from the decidual tissue. Extracellular vesicles (EVs) with microRNA (miRNA) between cells have been regarded as critical factors for embryo–maternal interactions on embryo implantation and programming of human pregnancy. MicroRNA-138-5p acts as the transcriptional regulator of GPR124 and the mediator of downstream inflammasome. LIF-regulated STAT activation and expression of integrins might influence embryo implantation. Hence, a better understanding of LIF–STAT and adhesion molecule signaling would elucidate the mechanism of microRNA-138-5p- and GPR124-regulated inflammasome activation on embryo implantation and pregnancy. Our results show that microRNA-138-5p, purified from the EVs of decidual stromal cells, inhibits the expression of GPR124 and the inflammasome, and activates the expression of LIF–STAT and adhesion molecules in human decidual stromal cells. Additionally, the knockdown of GPR124 and NLRP3 through siRNA increases the expression of LIF–STAT and adhesion molecules. The findings of this study help us gain a better understanding the role of EVs, microRNA-138-5p, GPR124, inflammasomes, LIF–STAT, and adhesion molecules in embryo implantation and programming of human pregnancy.

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Abigail R Walker Institute of Reproductive and Developmental Biology, Department Metabolism, Digestion and Reproduction, Imperial College London, London, UK

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Holly A Parkin Institute of Reproductive and Developmental Biology, Department Metabolism, Digestion and Reproduction, Imperial College London, London, UK

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Sung Hye Kim Institute of Reproductive and Developmental Biology, Department Metabolism, Digestion and Reproduction, Imperial College London, London, UK

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Vasso Terzidou Institute of Reproductive and Developmental Biology, Department Metabolism, Digestion and Reproduction, Imperial College London, London, UK

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David F Woodward Department of Bioengineering, Imperial College London, London, UK

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Phillip R Bennett Institute of Reproductive and Developmental Biology, Department Metabolism, Digestion and Reproduction, Imperial College London, London, UK

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Aylin C Hanyaloglu Institute of Reproductive and Developmental Biology, Department Metabolism, Digestion and Reproduction, Imperial College London, London, UK

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The prostanoid G protein-coupled receptor (GPCR) EP2 is widely expressed and implicated in endometriosis, osteoporosis, obesity, pre-term labour and cancer. Internalisation and intracellular trafficking are critical for shaping GPCR activity, yet little is known regarding the spatial programming of EP2 signalling and whether this can be exploited pharmacologically. Using three EP2-selective ligands that favour activation of different EP2 pathways, we show that EP2 undergoes limited agonist-driven internalisation but is constitutively internalised via dynamin-dependent, β-arrestin-independent pathways. EP2 was constitutively trafficked to early and very early endosomes (VEE), which was not altered by ligand activation. APPL1, a key adaptor and regulatory protein of the VEE, did not impact EP2 agonist-mediated cAMP. Internalisation was required for ~70% of the acute butaprost- and AH13205-mediated cAMP signalling, yet PGN9856i, a Gαs-biased agonist, was less dependent on receptor internalisation for its cAMP signalling, particularly in human term pregnant myometrial cells that endogenously express EP2. Inhibition of EP2 internalisation partially reduced calcium signalling activated by butaprost or AH13205 and had no effect on PGE2 secretion. This indicates an agonist-dependent differential spatial requirement for Gαs and Gαq/11 signalling and a role for plasma membrane-initiated Gαq/11-Ca2+-mediated PGE2 secretion. These findings reveal a key role for EP2 constitutive internalisation in its signalling and potential spatial bias in mediating its downstream functions. This, in turn, could highlight important considerations for future selective targeting of EP2 signalling pathways.

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Weiye Zhao Department of Biology, University of York, York, UK

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Susanna F Rose Department of Biology, University of York, York, UK

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Ryan Blake CRUK Cambridge Institute, University of Cambridge, Cambridge, UK

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Aňze Godicelj Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Smith Building, Boston, Massachusetts, USA

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Amy E Cullen CRUK Cambridge Institute, University of Cambridge, Cambridge, UK

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Jack Stenning Department of Biology, University of York, York, UK

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Lucy Beevors The Institute of Metabolism and Systems Research (IMSR), University of Birmingham, College of Medical and Dental Sciences, Birmingham, UK

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Marcel Gehrung CRUK Cambridge Institute, University of Cambridge, Cambridge, UK

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Sanjeev Kumar Chris O’Brien Lifehouse, Sydney, New South Wales, Australia

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Kamal Kishore CRUK Cambridge Institute, University of Cambridge, Cambridge, UK

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Ashley Sawle CRUK Cambridge Institute, University of Cambridge, Cambridge, UK

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Matthew Eldridge CRUK Cambridge Institute, University of Cambridge, Cambridge, UK

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Federico M Giorgi Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy

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Katherine S Bridge Department of Biology, University of York, York, UK
York Biomedical Research Institute, University of York, York, UK

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Florian Markowetz CRUK Cambridge Institute, University of Cambridge, Cambridge, UK

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Andrew N Holding Department of Biology, University of York, York, UK
York Biomedical Research Institute, University of York, York, UK
The Alan Turing Institute, Kings Cross, London, UK

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The estrogen receptor-α (ER) drives 75% of breast cancers. On activation, the ER recruits and assembles a 1–2 MDa transcriptionally active complex. These complexes can modulate tumour growth, and understanding the roles of individual proteins within these complexes can help identify new therapeutic targets. Here, we present the discovery of ER and ZMIZ1 within the same multi-protein assembly by quantitative proteomics, and validated by proximity ligation assay. We characterise ZMIZ1 function by demonstrating a significant decrease in the proliferation of ER-positive cancer cell lines. To establish a role for the ER-ZMIZ1 interaction, we measured the transcriptional changes in the estrogen response post-ZMIZ1 knockdown using an RNA-seq time-course over 24 h. Gene set enrichment analysis of the ZMIZ1-knockdown data identified a specific delay in the response of estradiol-induced cell cycle genes. Integration of ENCODE data with our RNA-seq results identified that ER and ZMIZ1 both bind the promoter of E2F2. We therefore propose that ER and ZMIZ1 interact to enable the efficient estrogenic response at subset of cell cycle genes via a novel ZMIZ1–ER–E2F2 signalling axis. Finally, we show that high ZMIZ1 expression is predictive of worse patient outcome, ER and ZMIZ1 are co-expressed in breast cancer patients in TCGA and METABRIC, and the proteins are co-localised within the nuclei of tumour cell in patient biopsies. In conclusion, we establish that ZMIZ1 is a regulator of the estrogenic cell cycle response and provide evidence of the biological importance of the ER–ZMIZ1 interaction in ER-positive patient tumours, supporting potential clinical relevance.

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Marta Santos-Hernández Institute of Metabolic Science, Addenbrooke’s Hospital, Cambridge, UK

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Frank Reimann Institute of Metabolic Science, Addenbrooke’s Hospital, Cambridge, UK

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Fiona M Gribble Institute of Metabolic Science, Addenbrooke’s Hospital, Cambridge, UK

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Enteroendocrine cells located along the gastrointestinal epithelium sense different nutrients/luminal contents that trigger the secretion of a variety of gut hormones with different roles in glucose homeostasis and appetite regulation. The incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are involved in the regulation of insulin secretion, appetite, food intake and body weight after their nutrient-induced secretion from the gut. GLP-1 mimetics have been developed and used in the treatment of type 2 diabetes mellitus and obesity. Modulating the release of endogenous intestinal hormones may be a promising approach for the treatment of obesity and type 2 diabetes without surgery. For that reason, current understanding of the cellular mechanisms underlying intestinal hormone secretion will be the focus of this review. The mechanisms controlling hormone secretion depend on the nature of the stimulus, involving a variety of signalling pathways including ion channels, nutrient transporters and G-protein-coupled receptors.

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Yan Meng School of Life Sciences, University of Nottingham, Queen’s Medical Centre, Nottingham, UK

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Maria Toledo-Rodriguez School of Life Sciences, University of Nottingham, Queen’s Medical Centre, Nottingham, UK

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Olena Fedorenko School of Life Sciences, University of Nottingham, Queen’s Medical Centre, Nottingham, UK

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Paul A Smith School of Life Sciences, University of Nottingham, Queen’s Medical Centre, Nottingham, UK

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White adipose tissue (WAT) requires extracellular Ca2+ influx for lipolysis, differentiation, and expansion. This partly occurs via plasma membrane Ca2+ voltage-dependent channels (CaVs). However, WFA exists in different depots whose function varies with age, sex, and location. To explore whether their CaV expression profiles also differ we used RNAseq and qPCR on gonadal, mesenteric, retroperitoneal, and inguinal subcutaneous fat depots from rats of different ages and sex. CaV expression was found dependent on age, sex, and WFA location. In the gonadal depots of both sexes a significantly lower expression of CaV1.2 and CaV1.3 was seen for adults compared to pre-pubescent juveniles. A lower level of expression was also seen for CaV3.1 in adult male but not female gonadal WFA, the latter of whose expression remained unchanged with age. Relatively little expression of CaV3.2 and 3.2 was observed. In post-pubescent inguinal subcutaneous fat, where the third and fourth mammary glands are located, CaV3.1 was decreased in males but increased in females – thus suggesting that this channel is associated with mammogenesis; however, no difference in intracellular Ca2+ levels or adipocyte size were noted. For all adult depots, CaV3.1 expression was larger in females than males – a difference not seen in pre-pubescent rats. These observations are consistent with the changes of CaV3.1 expression seen in 3T3-L1 cell differentiation and the ability of selective CaV3.1 antagonists to inhibit adipogensis. Our results show that changes in CaV expression patterns occur in fat depots related to sexual dimorphism: reproductive tracts and mammogenesis.

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Jenica H Kakadia Department of Biochemistry, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada
Children's Health Research Institute, London, Ontario, Canada

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Muhammad U Khalid Department of Biochemistry, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada

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Ilka U Heinemann Department of Biochemistry, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada

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Victor K Han Department of Biochemistry, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada
Children's Health Research Institute, London, Ontario, Canada
Department of Pediatrics, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada

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Mechanisms underlying limitations in glucose supply that restrict fetal growth are not well established. IGF-1 is an important regulator of fetal growth and IGF-1 bioavailability is markedly inhibited by IGFBP-1 especially when the binding protein is hyperphosphorylated. We hypothesized that the AMPK–mTORC1 pathway increases IGFBP-1 phosphorylation in response to glucose deprivation. Glucose deprivation in HepG2 cells activated AMPK and TSC2, inhibited mTORC1 and increased IGFBP-1 secretion and site-specific phosphorylation. Glucose deprivation also decreased IGF-1 bioavailability and IGF-dependent activation of IGF-1R. AICAR (an AMPK activator) activated TSC2, inhibited mTORC1, and increased IGFBP-1 secretion/phosphorylation. Further, siRNA silencing of either AMPK or TSC2 prevented mTORC1 inhibition and IGFBP-1 secretion and phosphorylation in glucose deprivation. Our data suggest that the increase in IGFBP-1 phosphorylation in response to glucose deprivation is mediated by the activation of AMPK/TSC2 and inhibition of mTORC1, providing a possible mechanistic link between glucose deprivation and restricted fetal growth.

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Isabelle Durrer Department of Nephrology and Hypertension University of Bern, Berne, Switzerland

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Daniel Ackermann Department of Nephrology and Hypertension University of Bern, Berne, Switzerland

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Rahel Klossner Department of Nephrology and Hypertension University of Bern, Berne, Switzerland
Department of Internal Medicine, Sonnenhof, Lindenhofgruppe, Berne, Switzerland

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Michael Grössl Department of Nephrology and Hypertension University of Bern, Berne, Switzerland

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Clarissa Vögel Department of Nephrology and Hypertension University of Bern, Berne, Switzerland

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Therina Du Toit Department for BioMedical Research University of Bern, Berne, Switzerland

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Bruno Vogt Department of Nephrology and Hypertension University of Bern, Berne, Switzerland

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Heidi Jamin Department of Nephrology and Hypertension University of Bern, Berne, Switzerland
Department for BioMedical Research University of Bern, Berne, Switzerland

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Markus G Mohaupt Department of Internal Medicine, Sonnenhof, Lindenhofgruppe, Berne, Switzerland
Department for BioMedical Research University of Bern, Berne, Switzerland

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Carine Gennari-Moser Department of Nephrology and Hypertension University of Bern, Berne, Switzerland
Department for BioMedical Research University of Bern, Berne, Switzerland

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Extra-adrenal de novo aldosterone (Aldo) production has been described inconsistently. Systematic data based upon state-of-the-art technology including validated controls are sparse. We hypothesized that aldosterone synthase (CYP11B2) expression and de novo Aldo production are absent in nonadrenal human cell lines, either immortalized cell lines or commercially available primary cell lines, including peripheral blood mononuclear cells (PBMCs) of individuals without and with primary hyperaldosteronism (PA). CYP11B2-transfected COS-7 and endogenous CYP11B2 expressing adrenal H295R cells served as positive controls. Various well-characterized, purchased, immortalized (BeWo, HEK293, HTR-8/SVneo, JEG-3) and primary (HAEC, HLEC, HRGEC, HRMC, HUAEC, HUVEC, PBMC) cell lines as well as self-isolated PBMCs from PA patients (n = 5) were incubated with the steroid hormone substrates progesterone, deoxycorticosterone, corticosterone or 18-OH-corticosterone with and without Ang II for 24 h to assess CYP11B2 enzymatic activity. CYP11B2 expression was analyzed by real-time PCR and liquid chromatography–mass spectrometry was used to quantify Aldo production. Pronounced CYP11B2 mRNA expression and Aldo production were observed in both positive controls, which followed an incremental time course. Neither substrates alone nor coincubation with Ang II significantly stimulated CYP11B2 expression or Aldo production in various immortalized and primary cell lines and PBMCs of PA patients. These results strongly support the absence of relevant de novo extra-adrenal Aldo production in nonadrenal cells, including blood mononuclear cells, irrespective of the absence or presence of autonomous adrenal Aldo production.

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Xiaojing Wei Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, Xi’an Jiaotong University, Xi’an, China
Institute of Neuroscience, Translational Medicine Institute, Xi’an Jiaotong University Health Science Center, Xi’an, China

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Yutian Tan Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, Xi’an Jiaotong University, Xi’an, China
Institute of Neuroscience, Translational Medicine Institute, Xi’an Jiaotong University Health Science Center, Xi’an, China

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Jiaqi Huang Institute of Basic Medicine, School of Medicine, Tsinghua University, Beijing, China

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Ximing Dong Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, Xi’an Jiaotong University, Xi’an, China
Institute of Neuroscience, Translational Medicine Institute, Xi’an Jiaotong University Health Science Center, Xi’an, China

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Weijie Feng Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, Xi’an Jiaotong University, Xi’an, China
Institute of Neuroscience, Translational Medicine Institute, Xi’an Jiaotong University Health Science Center, Xi’an, China

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Tanglin Liu Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, Xi’an Jiaotong University, Xi’an, China
Institute of Neuroscience, Translational Medicine Institute, Xi’an Jiaotong University Health Science Center, Xi’an, China

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Zhao Yang Department of Obstetrics and Gynecology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China

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Guiying Yang Department of Obstetrics and Gynecology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China

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Xiao Luo Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, Xi’an Jiaotong University, Xi’an, China
Institute of Neuroscience, Translational Medicine Institute, Xi’an Jiaotong University Health Science Center, Xi’an, China

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N1-methylnicotinamide (MNAM), a product of methylation of nicotinamide through nicotinamide N-methyltransferase, displays antidiabetic effects in male rodents. This study aimed to evaluate the ameliorative potential of MNAM on glucose metabolism in a gestational diabetes mellitus (GDM) model. C57BL/6N mice were fed with a high-fat diet (HFD) for 6 weeks before pregnancy and throughout gestation to establish the GDM model. Pregnant mice were treated with 0.3% or 1% MNAM during gestation. MNAM supplementation in CHOW diet and HFD both impaired glucose tolerance at gestational day 14.5 without changes in insulin tolerance. However, MNAM supplementation reduced hepatic lipid accumulation as well as mass and inflammation in visceral adipose tissue. MNAM treatment decreased GLUT4 mRNA and protein expression in skeletal muscle, where NAD+ salvage synthesis and antioxidant defenses were dampened. The NAD+/sirtuin system was enhanced in liver, which subsequently boosted hepatic gluconeogenesis. GLUT1 protein was diminished in placenta by MNAM. In addition, weight of placenta, fetus weight, and litter size were not affected by MNAM treatment. The decreased GLUT4 in skeletal muscle, boosted hepatic gluconeogenesis and dampened GLUT1 in placenta jointly contribute to the impairment of glucose tolerance tests by MNAM. Our data provide evidence for the careful usage of MNAM in treatment of GDM.

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Deyana Ivanova Department of Women and Children’s Health, Faculty of Life Science and Medicine, King’s College London, UK
Division of Endocrinology, Diabetes, and Hypertension, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, USA

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Kevin T O’Byrne Department of Women and Children’s Health, Faculty of Life Science and Medicine, King’s College London, UK

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The exact neural construct underlying the dynamic secretion of gonadotrophin-releasing hormone (GnRH) has only recently been identified despite the detection of multiunit electrical activity volleys associated with pulsatile luteinising hormone (LH) secretion four decades ago. Since the discovery of kisspeptin/neurokinin B/dynorphin neurons in the mammalian hypothalamus, there has been much research into the role of this neuronal network in controlling the oscillatory secretion of gonadotrophin hormones. In this review, we provide an update of the progressive application of cutting-edge techniques combined with mathematical modelling by the neuroendocrine community, which are transforming the functional investigation of the GnRH pulse generator. Understanding the nature and function of the GnRH pulse generator can greatly inform a wide range of clinical studies investigating infertility treatments.

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