bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identification and Characterization of a New Member of the Placental Prolactin-Like Protein-C (PLP-C) Subfamily, PLP-Cβ*
Authors: Hwang In-Taek , Lee Yong-Hun , Moon Boung-Cheon , Ahn Kyu-Youn , Lee See-Woo , Chun Jong-Yoon 
Published: January 2014

AbstractWe have isolated a complementary DNA (cDNA) clone that encodes a new member of the PRL-like protein-C (PLP-C) subfamily of the PRL gene family. The clone was amplified from a 13.5-day-old mouse conceptus cDNA library by PCR using primers based on conserved regions of PLP-C sequences. The full-length cDNA encodes a predicted protein of 241 residues, which contains a putative signal sequence and 2 putative N-linked glycosylation sites. The predicted protein shares 55–66% amino acid identity with mouse PLP-Cα and rat PLP-D, PLP-H, PLP-Cv, and PLP-C and also contains 6 homologously positioned cysteine residues. Thus, we named this protein PLP-Cβ for consistency. We have also isolated rat PLP-Cβ from rat placenta cDNA library. Surprisingly, two messenger RNA (mRNA) isoforms of rat PLP-Cβ were isolated: one mRNA (rPLP-Cβ) encodes a 241-amino acid product, but another mRNA (rPLP-CβΔ39) lacks 39 bases that encode for a region rich in aromatic amino acids. The 39-bp region corresponds to exon 3 of other PLP-C subfamily members, such as PLP-Cα, PLP-Cv, and d/tPRP. It suggests that the two isoforms are probably generated by an alternative splicing from a single gene. RT-PCR analysis revealed that the rPLP-Cβ form was dominantly expressed in placenta, although both isoforms are coexpressed during placentation. The mouse PLP-Cβ mRNA expression, which was specific to the placenta, was first detected by Northern analysis on embryonic day 11.5 (E 11.5) and persisted until birth. However, in situ hybridization analysis revealed mPLP-Cβ expression on E 10.5 in specific trophoblast subsets, such as giant cells and spongiotrophoblast cells. mPLP-Cβ mRNA was detected in the labyrinthine zone on E 18.5, suggesting that spongiotrophoblast cells had penetrated the labyrinthotrophoblast zone. Consistent with the observed expression in trophoblast giant cells, PLP-Cβ expression was also detected in in vitro differentiated Rcho-1 cells, which express the trophoblast giant cell phenotype. In summary, overall high amino acid identity (79%), the locations of cysteine residues, and consensus sites for N-linked glycosylation between mouse and rat PLP-Cβ clearly indicate that PLP-Cβ is a bona fide member of the PLP-C subfamily. The conservation between mouse and rat, the presence of alternative isoforms, and the pattern of expression during gestation suggest the biological significance of PLP-Cβ during pregnancy.
Transcriptional Regulation of Insulin-Like Growth Factor-I Receptor Gene Expression in Prostate Cancer Cells**This work was supported by V.A. Merit Review Program (to S.R.P.), DAMD 17–98-1–8540 (to J.L.W.), NIH DK-52683 (to S.R.P. and J.L.W.), and NIH DK-50810 (to C.T.R.). The content of this report does not necessarily represent the position or the policy of the United States government, and no official endorsement should be inferred.
Authors: Damon Susan E. , Plymate Stephen R. , Carroll Julie M. , Sprenger Cynthia C. , Dechsukhum Chevaboon , Ware Joy L. , Roberts Charles T. 
Published: January 2014

AbstractA marked decrease in the type 1 insulin-like growth factor (IGF) receptor (IGF-IR) occurs in prostate epithelial cells during transformation from the benign to the metastatic state. One of the principal regulators of IGF-IR gene expression, the WT1 tumor suppressor, is expressed in prostate cancer and in prostate cancer cell lines. The purpose of this study was to determine whether the decrease in IGF-IR expression was transcriptionally regulated, and whether WT1 action may be involved in the repression of the IGF-IR gene in prostate cancer cells. The P69 cell line was derived by immortalization of human primary prostate epithelial cells with simian virus-40 T antigen and is rarely tumorigenic. The M12 line was derived from the P69 line by selection for tumor formation in nude mice and is tumorigeneic and metastatic. P69 cells express 20,000 IGF-IR/cell, whereas M12 cells express 3,500 IGF-IR/cell. These differences in receptor number are reflected in proportional differences in IGF-IR mRNA levels. To assess IGF-IR promoter activity in these cell lines, each was transiently transfected with luciferase reporter vectors containing the IGF-IR gene transcription start site and 476 bp of 5′-flanking sequence, 640 bp of 5′-untranslated region sequence, or both regions. The promoter activity of the full-length construct was 50% lower (P &lt; 0.01) in M12 cells compared with P69 cells, the activity of the 5′-flanking region construct was 53% lower (P &lt; 0.0001), and that of the 5′-untranslated region construct was 36% lower (P = 0.01). P69 clones stably transfected with a WT1 expression vector exhibited decreased expression of the endogenous IGF-IR gene and decreased promoter activity in transient transfection assays with IGF-IR promoter constructs containing multiple WT1 binding sites. The observed reduction in endogenous IGF-IR expression was sufficient to inhibit IGF-I-stimulated cell proliferation. These data suggest that most of the decreased expression of the IGF-IR seen in malignant prostate epithelium is the result of transcriptional repression of the IGF-IR gene, and that this repression may be due in part to the increased expression of the WT1 tumor suppressor in metastatic prostate cancer.
Phosphatidylinositol-3,4,5-Trisphosphate Is Required for Insulin-Like Growth Factor 1-Mediated Survival of 3T3-L1 Preadipocytes**This work was supported by a grant (to A.S.) from the Medical Research Council of Canada.
Authors: Gagnon AnneMarie , Dods Patti , Roustan-Delatour Nicolas , Chen Ching-Shih , Sorisky Alexander 
Published: January 2014

AbstractAdipocyte number, a determinant of adipose tissue mass, reflects the balance between the rates of proliferation/differentiation vs. apoptosis of preadipocytes. The percentage of 3T3-L1 preadipocytes undergoing cell death following serum deprivation was reduced by 10 nm insulin-like growth factor (IGF)-1 (from 50.0 ± 0.7% for control starved cells to 27.5 ± 3.1%). TUNEL staining confirmed the apoptotic nature of the cell death. The protective effect of IGF-1 was blocked by phosphoinositide 3-kinase (PI3K) inhibitors, wortmannin, and LY294002, but was unaffected by rapamycin, PD98059, or SB203580, which inhibit mammalian target of rapamycin (mTOR), ERK kinase (MEK1), and p38 MAPK respectively. Exogenous PI(3,4,5)P3 (10 μm), the principal product of IGF-1-stimulated PI3K in 3T3-L1 preadipocytes, had a modest survival effect on its own, reducing cell death from 47.9± 3.4% to 35.6 ± 3.5%. When added to the combination of IGF-1 and LY294002, PI(3,4,5)P3 reversed most of the inhibitory effect of LY294002 on IGF-1-dependent cell survival, protein kinase B/Akt phosphorylation, and caspase-3 activity. Taken together, these results implicate PI(3,4,5)P3 as a necessary signal for the anti-apoptotic action of IGF-1 on 3T3-L1 preadipocytes.
Induction of Type 3 Iodothyronine Deiodinase by Nerve Injury in the Rat Peripheral Nervous System
Authors: Li Wen Wu , Le Goascogne Claude , Ramaugé Martine , Schumacher Michael , Pierre Michel , Courtin Françoise 
Published: January 2014

AbstractThyroid hormones are essential for the development and repair of the peripheral nervous system. The type 2 deiodinase, which is responsible for the activation of T4 into T3, is induced in injured sciatic nerve. To obtain information on the type 3 deiodinase (D3) responsible for the degradation of thyroid hormones, we looked for its expression (mRNA and activity) in the sciatic nerve after injury. D3 was undetectable in the intact sciatic nerve of adult rats, but was rapidly and highly increased in the distal and proximal segments after nerve lesion. After cryolesion, D3 up-regulation disappeared after 3 d in the proximal segment, whereas it was sustained for 10 d in the distal segment, then declined to reach basal levels after 28 d, when functional recovery was completed. After a transsection preventing the nerve regeneration, up-regulation of D3 persisted up to 28 d at high levels in the distal segment. D3 was expressed in peripheral connective sheaths and in the internal endoneural compartment. D3 mRNA was inducible by 12-O-tetradecanoylphorbol-13-acetate in cultured fibroblasts or Schwann cells. In conclusion, induction of D3 in the peripheral nervous system after injury may play an important role during the regeneration process by adjusting intracellular T3 levels.
Quantitative Analysis of Estrogen Receptor Proteins in Rat Mammary Gland*
Authors: Saji Shigehira , Sakaguchi Hideki , Andersson Sandra , Warner Margaret , Gustafsson Jan-Åke 
Published: January 2014

Abstract
Estrogen receptor α and β proteins (ERα and ERβ) at various stages of development of the rat mammary gland were quantified by Western blotting. ERα and ERβ recombinant proteins were used as standards, and their molar concentrations were measured by ligand binding assays. In 3-week-old pregnant, lactating, and postlactating rats the ERα content ranged from 0.30–1.55 fmol/μg total protein (mean values). The ERβ content of the same samples ranged between 1.06–7.50 fmol/μg total protein. At every developmental stage, the ERβ content of the mammary gland was higher than that of ERα. When receptor levels were normalized against β-actin, it was evident that ER expression changed during development, with maximum expression of both receptors during the lactation period. With an antibody raised against the 18-amino acid insert of the ERβ variant, originally called ERβ2 but named ERβins in this paper, Western blots revealed that ERβins protein was up-regulated during the lactation period. RT-PCR showed that the levels of messenger RNA of ERβins paralleled those of the protein. Double immunohistochemical staining with anti-ERα and anti-ERβins antibodies revealed that ERβins protein colocalized with ERα in 70–80% of the ERα-expressing epithelial cells during lactation and with 30% of these cells during pregnancy. These observations indicate that expression of ERβins is regulated not only quantitatively, but also with regard to its cellular distribution. As ERβins acts as the dominant repressor of ERα, we suggest that its coexpression with ERα quenches ERα function and may be one of the factors that contribute to the previously described insensitivity of the mammary gland to estrogens during lactation.
Inhibin Suppresses and Activin Stimulates Osteoblastogenesis and Osteoclastogenesis in Murine Bone Marrow Cultures
Authors: Gaddy-Kurten D. , Coker J. K. , Abe E. , Jilka R. L. , Manolagas S. C. 
Published: January 2014

AbstractUsing primary murine bone marrow cell cultures, we demonstrate that inhibin suppresses osteoblastogenesis and osteoclastogenesis. In contrast, activin supports osteoblast formation (by alkaline phosphatase-positive and mineralized colony formation); and activin also stimulates osteoclast formation (as measured by staining tartrate-resistant acid phosphatase-positive multinucleated cells). Inhibin, the activin antagonist follistatin, and the bone morphogenetic protein antagonist noggin can all suppress endogenous activin accumulation in bone marrow cultures. Associated with this decrease in activin is the loss of mineralized osteoblastic colony formation (colony forming unit-osteoblast; CFU-OB). However, exogenous activin administration, even in the presence of noggin, permits both alkaline phosphatase-positive and CFU-OB colony formation in vitro. In contrast, the stimulatory effects of locally produced activin on osteoblast and osteoclast development are not likely to be dominant over the suppressive effects of gonadally derived inhibin. The suppressive effect of inhibin is maintained in the presence of either activin or bone morphogenetic protein, suggesting the presence of a distinct inhibin-specific receptor. Taken together, the direct regulation of osteoblastogenesis and osteoclastogenesis by inhibin and activin in vitro suggest that changes in the inhibin/activin ratio detected by bone marrow cells, during the perimenopausal transition, contribute to altered cell differentiation and may be associated with the increased bone resorption observed at this time.
11β-Hydroxysteroid Dehydrogenase 1 Transforms 11-Dehydrocorticosterone into Transcriptionally Active Glucocorticoid in Neonatal Rat Heart
Authors: Sheppard Karen E. , Autelitano Dominic J. 
Published: January 2014

AbstractThe ability of cells to directly respond to glucocorticoids and aldosterone is a function of GR and MR expression, and coexpression of 11β-hydroxysteroid dehydrogenases (11βHSDs), which convert glucocorticoids and their 11-ketometabolites into either receptor inactive or active derivatives. The aim of the present study was to determine the cellular expression of GR, MR, 11βHSD1, and 11βHSD2 in neonatal rat heart and determine the role these enzymes play in modulating glucocorticoid and aldosterone action. Ribonuclease protection analysis and steroid binding assays showed that GR is expressed in both cardiac myocytes and fibroblasts, whereas MR is expressed only in myocytes. 11βHSD2 was not detected in cardiac cells, but 11βHSD1 was expressed at high levels in both cardiac myocytes and fibroblasts. Enzyme activity studies demonstrated that 11βHSD1 acted as a reductase only, converting biologically inactive 11-dehydrocorticosterone to corticosterone, which then stimulated serum and glucocorticoid-induced kinase gene transcription via GR. In both cardiac myocytes and fibroblasts, aldosterone stimulated serum and glucocorticoid-induced kinase gene expression exclusively via GR, but not MR, indicating that aldosterone can have glucocorticoid-like actions in heart. The ability of cardiac cells to use both circulating corticosterone and 11-dehydrocorticosterone as a source of glucocorticoid suggests that the heart is under tonic glucocorticoid control, implying that glucocorticoids play important homeostatic roles in the heart.
Double-Stranded RNA Cooperates with Interferon-γ and IL-1β to Induce Both Chemokine Expression and Nuclear Factor-κB-Dependent Apoptosis in Pancreatic β-Cells: Potential Mechanisms for Viral-Induced Insulitis and β-Cell Death in Type 1 Diabetes Mellitus
Authors: Liu Dongbo , Cardozo Alessandra K. , Darville Martine I. , Eizirik Décio L. 
Published: January 2014

AbstractViral infections may trigger the autoimmune assault leading to type 1 diabetes mellitus. Double-stranded RNA (dsRNA) is produced by many viruses during their replicative cycle. The dsRNA, tested as synthetic poly(IC) (PIC), in synergism with the proinflammatory cytokines interferon-γ (IFN-γ) and/or IL-1β, results in nitric oxide production, Fas expression, β-cell dysfunction, and death. Activation of the transcription nuclear factor-κB (NF-κB) is required for PIC-induced inducible nitric oxide synthase expression in β-cells, and we hypothesized that this transcription factor may also participate in PIC-induced Fas expression and β-cell apoptosis. This hypothesis, and the possibility that PIC induces expression of additional chemokines and cytokines (previously reported as NF-κB dependent) in pancreatic β-cells, was investigated in the present study. We observed that the PIC-responsive region in the Fas promoter is located between nucleotides −223 and −54. Site-directed mutations at the NF-κB and CCAAT/enhancer binding protein-binding sites prevented PIC-induced Fas promoter activity. Increased Fas promoter activity was paralleled by enhanced susceptibility of PIC + cytokine-treated β-cells to apoptosis induced by Fas ligand. β-Cell infection with the NF-κB inhibitor AdIκB(SA)2 prevented both necrosis and apoptosis induced by PIC + IL-1β or PIC + IFN-γ. Messenger RNAs for several chemokines and one cytokine were induced by PIC, alone or in combination with IFN-γ, in pancreatic β-cells. These included IP-10, interferon-γ-inducible protein-10, IL-15, macrophage chemoattractant protein-1, fractalkine, and macrophage inflammatory protein-3α. There was not, however, induction of IL-1β expression. We propose that dsRNA, generated during a viral infection, may contribute for β-cell demise by both inducing expression of chemokines and IL-15, putative contributors for the build-up of insulitis, and by synergizing with locally produced cytokines to induce β-cell apoptosis. Activation of the transcription factor NF-κB plays a central role in at least part of the deleterious effects of dsRNA in pancreatic β-cells.
Prenatal LHRH Neurons in Nasal Explant Cultures Express Estrogen Receptor β Transcript
Authors: Sharifi Neda , Reuss Andree E. , Wray Susan 
Published: January 2014

AbstractSex steroids influence LHRH neuronal activity, exerting a negative or positive feedback action, depending on the reproductive state of the animal. Recent evidence indicates that LHRH neurons possess the estrogen receptor β (ERβ) subtype postnatally, suggesting that estrogen may act, in part, directly on LHRH neurons. In this study, we identified ERβ transcript in prenatal LHRH neurons as a function of age. Single-cell cDNA pools were made from LHRH neurons maintained for 7, 14, and 28 d in vitro (div). Screening of the cDNA pools by PCR with ERβ-specific primers revealed ERβ-positive LHRH neurons at all three ages. However, the number of LHRH cells coexpressing ERβ transcript decreased dramatically between 14 (6/10) and 28 div (1/10). None of the LHRH cells were positive for ERα transcript. These results indicate that developing LHRH neurons express the transcript for ERβ and suggest that continued expression of ERβ is either a characteristic of LHRH neurons that may require cues from the central nervous system and/or periphery or predetermined to be maintained in a subpopulation of LHRH neurons.
The Somatostatin Analog Octreotide Inhibits GH-Stimulated, But Not IGF-I-Stimulated, Bone Growth in Hypophysectomized Rats
Authors: Zapf Jürgen , Gosteli-Peter Martina , Weckbecker Gisbert , Hunziker Ernst B. , Reinecke Manfred 
Published: January 2014

AbstractIGF-I mediates growth-promoting actions of GH. In the present study we investigated whether the somatostatin analog octreotide blunts the stimulatory effects of GH and/or IGF-I on bone growth in hypophysectomized rats infused for 6 d with vehicle, GH, or IGF-I. We found that octreotide significantly suppressed the GH-induced rise in liver IGF-I mRNA (−27%) and peptide (−32%) and the serum IGF-I level (−26%) and concomitantly inhibited GH-stimulated, but not IGF-I-stimulated, body weight gain (−31%), tibial epiphyseal width (−14%), and bone growth rate (−24%). Furthermore, octreotide significantly reduced the GH-induced increase in the number of IGF-I immunoreactive chondrocytes in all layers (except in the upper hypertrophic zone) of the tibial growth plate cartilage (P &lt; 0.0001 for stem cell and proliferative zone; P &lt; 0.0005 for lower hypertrophic zone). These findings demonstrate that octreotide does not interfere with IGF-I action, but does interfere with local GH-stimulated IGF-I production in the growth plate. Thus, besides inhibiting pituitary GH secretion, octreotide exerts inhibitory peripheral effects on GH-stimulated longitudinal bone growth.
Coexpression of Dopamine and Somatostatin Receptor Subtypes in Corticotroph Adenomas
Authors: de Bruin Christiaan , Pereira Alberto M. , Feelders Richard A. , Romijn Johannes A. , Roelfsema Ferdinand , Sprij-Mooij Diane M. , van Aken Maarten O. , van der Lelij Aart-Jan , de Herder Wouter W. , Lamberts Steven W. J. , Hofland Leo J. 
Published: January 2014

Abstract
Context: Previous studies have demonstrated the expression of somatostatin receptor subtypes (mainly sst5) and dopamine (DA) receptor subtypes (mainly D2) in smaller series of human corticotroph adenomas. In line with these findings, sst5 and D2-targeting agents have already been used clinically in patients with Cushing’s disease (CD) and have shown promising results in subsets of patients. To what extent these receptor subtypes are coexpressed within individual adenomas, is not known however.
Objective: The aim of the study was to investigate the (co-)expression of both sst and DA receptors in a large series of human corticotroph adenomas.
Design: We conducted in vitro analysis of corticotroph adenoma tissue obtained via transsphenoidal adenomectomy.
Setting: The study was conducted at two university medical centers.
Patients: Thirty patients with CD participated in the study.
Results: Analyzed by quantitative RT-PCR, D2 and sst5 were significantly (co-) expressed in the majority (60%) of adenomas, whereas 23% of adenomas only expressed D2, but not sst5. The remaining 17% of adenomas did not significantly express either sst5 or D2. Overall, expression of sst1–4 and D4 was low to nondetectable. Corticotroph adenomas with invasive growth invariably showed loss of sst5 and D2 expression. Autoradiography revealed clear D2 and/or SS-14 binding in a subset of cases, which correlated well with their respective mRNA data.
Conclusions: sst5 and especially D2 are highly expressed in the majority of human corticotroph adenomas, with coexpression of sst5 and D2 being a common phenomenon. These findings support the current studies with sst5 and D2-targeting agents in patients with CD and highlight the rationale behind sst5-D2 combination therapy.
Increased Hypothalamic-Pituitary-Adrenal Axis Activity in Huntington’s Disease
Authors: Aziz N. Ahmad , Pijl Hanno , Frölich Marijke , van der Graaf A. W. Maurits , Roelfsema Ferdinand , Roos Raymund A. C. 
Published: January 2014

Abstract
Context: Huntington’s disease (HD) is a fatal hereditary neurodegenerative disorder characterized by motor, cognitive, and behavioral disturbances. Hypothalamic-pituitary-adrenal (HPA) axis dysfunction could contribute to a number of HD signs and symptoms; however, no data are available on cortisol diurnal variations and secretory dynamics in HD patients.
Objective: The aim of the study was to perform a detailed analysis of HPA axis function in HD patients in relation to clinical signs and symptoms.
Design, Setting, and Participants: Twenty-four-hour cortisol secretion was studied in eight early-stage, medication-free HD patients and eight age-, sex-, and body mass index-matched controls in a clinical research laboratory. Cortisol levels were measured every 10 min.
Main Outcome Measures: Multiparameter autodeconvolution and cosinor regression were applied to quantify basal, pulsatile, and total cortisol secretion rates as well as diurnal variations in cortisol levels.
Results: Total cortisol secretion rate and the amplitude of the diurnal cortisol profile were both significantly higher in HD patients compared with controls (3490 ± 320 vs. 2500 ± 220 nmol/liter/24 h, P = 0.023; and 111 ± 14 vs. 64 ± 8 nmol/liter, P = 0.012, respectively). Cortisol concentrations in patients were particularly increased in the morning and early afternoon period. In HD patients, mean 24-h cortisol levels significantly correlated with total motor score, total functional capacity, as well as body mass index.
Conclusions: HPA axis hyperactivity is an early feature of HD and is likely to result from a disturbed central glucocorticoid feedback due to hypothalamic pathology. HPA axis dysfunction may contribute to some signs and symptoms in HD patients.