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1.
Nat Commun ; 14(1): 7096, 2023 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-37925459

RESUMEN

Disrupted circadian rhythms have been linked to an increased risk of hypertension and cardiovascular disease. However, many studies show inconsistent findings and are not sufficiently powered for targeted subgroup analyses. Using the UK Biobank cohort, we evaluate the association between circadian rhythm-disrupting behaviours, blood pressure (SBP, DBP) and inflammatory markers in >350,000 adults with European white British ancestry. The independent U-shaped relationship between sleep length and SBP/DBP is most prominent with a low inflammatory status. Poor sleep quality and permanent night shift work are also positively associated with SBP/DBP. Although fully adjusting for BMI in the linear regression model attenuated effect sizes, these associations remain significant. Two-sample Mendelian Randomisation (MR) analyses support a potential causal effect of long sleep, short sleep, chronotype, daytime napping and sleep duration on SBP/DBP. Thus, in the current study, we present a positive association between circadian rhythm-disrupting behaviours and SBP/DBP regulation in males and females that is largely independent of age.


Asunto(s)
Horario de Trabajo por Turnos , Trastornos del Inicio y del Mantenimiento del Sueño , Adulto , Masculino , Femenino , Humanos , Presión Sanguínea/fisiología , Bancos de Muestras Biológicas , Sueño/fisiología , Ritmo Circadiano/fisiología , Inflamación , Reino Unido
2.
Vitam Horm ; 123: 285-312, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37717989

RESUMEN

The cellular response to the adrenal steroid aldosterone is mediated by the mineralocorticoid receptor (MR), a member of the nuclear receptor superfamily of ligand-dependent transcription factors. The MR binds more than one physiological ligand with binding at the MR determined by pre-receptor metabolism of glucocorticoid ligands by 11ß hydroxysteroid dehydrogenase type 2. The MR has a wide tissue distribution with multiple roles beyond the classical role in electrolyte homeostasis including cardiovascular function, immune cell signaling, neuronal fate and adipocyte differentiation. The MR has three principal functional domains, an N-terminal ligand domain, a central DNA binding domain and a C-terminal, ligand binding domain, with structures having been determined for the latter two domains but not for the whole receptor. MR signal-transduction can be best viewed as a series of interactions which are determined by the conformation conferred on the receptor by ligand binding. This conformation then determines subsequent intra- and inter-molecular interactions. These interactions include chromatin, coregulators and other transcription factors, and additional less well characterized cytoplasmic non-genomic effects via crosstalk with other signaling pathways. This chapter will provide a review of MR structure and function, and an analysis of the critical interactions involved in MR-mediated signal transduction, which contribute to ligand- and tissue-specificity. Understanding the relevant mechanisms for selective MR signaling in terms of these interactions opens the possibility of novel therapeutic approaches for the treatment of MR-mediated diseases.


Asunto(s)
Aldosterona , Receptores de Mineralocorticoides , Humanos , Ligandos , Transducción de Señal , Relación Estructura-Actividad
3.
J Endocrinol ; 259(1)2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37486000

RESUMEN

Primary aldosteronism, or Conn syndrome, is the most common endocrine cause of hypertension. It is associated with a higher risk of cardiovascular, metabolic and renal diseases, as well as a lower quality of life than for hypertension due to other causes. The multi-systemic effects of primary aldosteronism can be attributed to aldosterone-mediated activation of the mineralocorticoid receptor in a range of tissues. In this review, we explore the signalling pathways of the mineralocorticoid receptor, with a shift from the traditional focus on the regulation of renal sodium-potassium exchange to a broader understanding of its role in the modulation of tissue inflammation, fibrosis and remodelling. The appreciation of primary aldosteronism as a multi-system disease with tissue-specific pathophysiology may lead to more vigilant testing and earlier institution of targeted interventions.


Asunto(s)
Hiperaldosteronismo , Hipertensión , Humanos , Hiperaldosteronismo/complicaciones , Receptores de Mineralocorticoides/metabolismo , Calidad de Vida , Antagonistas de Receptores de Mineralocorticoides , Aldosterona/metabolismo , Hipertensión/complicaciones
4.
Endocrine ; 79(1): 135-142, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36129592

RESUMEN

AIM: Although Graves' disease (GD) is common in endocrine practices worldwide, global differences in diagnosis and management remain. We sought to assess the current practices for GD in countries across Asia and the Pacific (APAC), and to compare these with previously published surveys from North America and Europe. METHODS: A web-based survey on GD management was conducted on practicing clinicians. Responses from 542 clinicians were received and subsequently analysed and compared to outcomes from similar surveys from other regions. RESULTS: A total of 542 respondents participated in the survey, 515 (95%) of whom completed all sections. Of these, 86% were medical specialists, 11% surgeons, and 3% nuclear medicine physicians. In addition to serum thyroid-stimulating hormone (TSH) and free thyroxine assays, most respondents would request TSH-receptor autoantibody (TRAb) measurement (68%) during initial work-up. Thyroid ultrasound is requested by about half of respondents (53%), while the use of nuclear medicine scans is limited. The preferred first-line treatment is anti-thyroid drug (ATD) therapy (79%) with methimazole (MMI) or carbimazole (CBZ), followed by radioiodine (RAI; 19%) and surgery (2%). In case of surgery, one-third of respondents would opt for a subtotal rather than a total thyroidectomy. In case of mild Graves orbitopathy (GO), ATDs (67%) remains the preferred treatment, but a larger proportion of clinicians prefer surgery (20%). For a patient with intention to conceive, the preferred treatment pattern remained unchanged, although propylthiouracil (PTU) became the preferred ATD-agent during the first trimester. In comparison to European and American practices, marked differences were noted in the relatively infrequent usage of nuclear medicine scans and the overall higher use of a ATDs and ß-blockers and adjunctive ATD-treatment during RAI in the APAC-group. CONCLUSION: Although regional differences regarding the diagnosis and management of GD are apparent in this first pan-Asia-Pacific survey, this study reveals the overall approach to the management of this disease in Asia-Pacific generally tends to fall between the trends appreciated in the American and European cohorts.


Asunto(s)
Enfermedad de Graves , Oftalmopatía de Graves , Humanos , Oftalmopatía de Graves/tratamiento farmacológico , Pautas de la Práctica en Medicina , Radioisótopos de Yodo/uso terapéutico , Enfermedad de Graves/diagnóstico , Enfermedad de Graves/terapia , Encuestas y Cuestionarios , Hormonas Tiroideas/uso terapéutico , Antitiroideos/uso terapéutico , Asia
5.
Neurobiol Dis ; 156: 105422, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34126164

RESUMEN

Synthetic glucocorticoids (sGCs) such as dexamethasone (DEX), while used to mitigate inflammation and disease progression in premature infants with severe bronchopulmonary dysplasia (BPD), are also associated with significant adverse neurologic effects such as reductions in myelination and abnormalities in neuroanatomical development. Ciclesonide (CIC) is a sGC prodrug approved for asthma treatment that exhibits limited systemic side effects. Carboxylesterases enriched in the lower airways convert CIC to the glucocorticoid receptor (GR) agonist des-CIC. We therefore examined whether CIC would likewise activate GR in neonatal lung but have limited adverse extra-pulmonary effects, particularly in the developing brain. Neonatal rats were administered subcutaneous injections of CIC, DEX or vehicle from postnatal days 1-5 (PND1-PND5). Systemic effects linked to DEX exposure, including reduced body and brain weight, were not observed in CIC treated neonates. Furthermore, CIC did not trigger the long-lasting reduction in myelin basic protein expression in the cerebral cortex nor cerebellar size caused by neonatal DEX exposure. Conversely, DEX and CIC were both effective at inducing the expression of select GR target genes in neonatal lung, including those implicated in lung-protective and anti-inflammatory effects. Thus, CIC is a promising, novel candidate drug to treat or prevent BPD in neonates given its activation of GR in neonatal lung and limited adverse neurodevelopmental effects. Furthermore, since sGCs such as DEX administered to pregnant women in pre-term labor can adversely affect fetal brain development, the neurological-sparing properties of CIC, make it an attractive alternative for DEX to treat pregnant women severely ill with respiratory illness, such as with asthma exacerbations or COVID-19 infections.


Asunto(s)
Cerebelo/efectos de los fármacos , Corteza Cerebral/efectos de los fármacos , Glucocorticoides , Pulmón/efectos de los fármacos , Pregnenodionas/farmacología , Profármacos/farmacología , Transducción de Señal/efectos de los fármacos , Animales , Animales Recién Nacidos , Antiinflamatorios/farmacología , Peso Corporal/efectos de los fármacos , Encéfalo/efectos de los fármacos , Encéfalo/crecimiento & desarrollo , Dexametasona/farmacología , Femenino , Ratones , Ratones Endogámicos C57BL , Proteína Básica de Mielina/biosíntesis , Tamaño de los Órganos/efectos de los fármacos , Embarazo , Ratas , Ratas Sprague-Dawley , Receptores de Glucocorticoides/efectos de los fármacos , Tratamiento Farmacológico de COVID-19
6.
Mol Cell ; 80(2): 279-295.e8, 2020 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-33065020

RESUMEN

The PTEN tumor suppressor controls cell death and survival by regulating functions of various molecular targets. While the role of PTEN lipid-phosphatase activity on PtdIns(3,4,5)P3 and inhibition of PI3K pathway is well characterized, the biological relevance of PTEN protein-phosphatase activity remains undefined. Here, using knockin (KI) mice harboring cancer-associated and functionally relevant missense mutations, we show that although loss of PTEN lipid-phosphatase function cooperates with oncogenic PI3K to promote rapid mammary tumorigenesis, the additional loss of PTEN protein-phosphatase activity triggered an extensive cell death response evident in early and advanced mammary tumors. Omics and drug-targeting studies revealed that PI3Ks act to reduce glucocorticoid receptor (GR) levels, which are rescued by loss of PTEN protein-phosphatase activity to restrain cell survival. Thus, we find that the dual regulation of GR by PI3K and PTEN functions as a rheostat that can be exploited for the treatment of PTEN loss-driven cancers.


Asunto(s)
Neoplasias Mamarias Animales/metabolismo , Neoplasias Mamarias Animales/patología , Fosfohidrolasa PTEN/metabolismo , Receptores de Glucocorticoides/metabolismo , Animales , Carcinogénesis , Muerte Celular , Línea Celular Tumoral , Proliferación Celular , Dexametasona/farmacología , Femenino , Humanos , Isoenzimas/metabolismo , Ratones , Modelos Biológicos , Mutación/genética , Organoides/patología , Fosfohidrolasa PTEN/genética , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación , Estabilidad Proteica , Proteoma/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo
7.
J Endocrinol ; 246(2): 123-134, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32464598

RESUMEN

MR activation in macrophages is critical for the development of cardiac inflammation and fibrosis. We previously showed that MR activation modifies macrophage pro-inflammatory signalling, changing the cardiac tissue response to injury via both direct gene transcription and JNK/AP-1 second messenger pathways. In contrast, MR-mediated renal electrolyte homeostasis is critically determined by DNA-binding-dependent processes. Hence, ascertaining the relative contribution of MR actions via DNA binding or alternative pathways on macrophage behaviour and cardiac inflammation may provide therapeutic opportunities which separate the cardioprotective effects of MR antagonists from their undesirable renal potassium-conserving effects. We developed new macrophage cell lines either lacking MR or harbouring a mutant MR incapable of DNA binding. Western blot analysis demonstrated that MR DNA binding is required for lipopolysaccharide (LPS), but not phorbol 12-myristate-13-acetate (PMA), induction of the MAPK/pJNK pathway in macrophages. Quantitative RTPCR for pro-inflammatory and pro-fibrotic targets revealed subsets of LPS- and PMA-induced genes that were either enhanced or repressed by the MR via actions that do not always require direct MR-DNA binding. Analysis of the MR target gene and profibrotic factor MMP12 identified promoter elements that are regulated by combined MR/MAPK/JNK signalling. Evaluation of cardiac tissue responses to an 8-day DOC/salt challenge in mice selectively lacking MR DNA-binding in macrophages demonstrated levels of inflammatory markers equivalent to WT, indicating non-DNA binding-dependent MR signalling in macrophages is sufficient for DOC/salt-induced tissue inflammation. Our data demonstrate that the MR regulates a macrophage pro-inflammatory phenotype and cardiac tissue inflammation, partially via pathways that do not require DNA binding.


Asunto(s)
Fibrosis/metabolismo , Inflamación/metabolismo , Miocardio/metabolismo , Receptores de Mineralocorticoides/metabolismo , Animales , Western Blotting , Lipopolisacáridos/farmacología , Macrófagos/metabolismo , Masculino , Metaloproteinasa 12 de la Matriz/metabolismo , Ratones , Receptores Citoplasmáticos y Nucleares/metabolismo
8.
J Mol Endocrinol ; 64(3): 155-164, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31958317

RESUMEN

Glucocorticoid (GC) signaling via the glucocorticoid receptor (GR) is essential for lung maturation in mammals. Previous studies using global or conditional mouse model knockouts of the GR gene have established that GR-mediated signaling in the interstitial mesenchyme of the fetal lung is critical for normal lung development. Screens for downstream GC-targets in conditional mesenchymal GR deficient mouse lung (GRmesKO) identified Versican (Vcan), an important extracellular matrix component and cell proliferation regulator, as a potential GR-regulated target. We show that, of the five major VCAN isoforms, the VCAN-V1 isoform containing the GAGß domain is the predominant VCAN isoform in the fetal mouse lung distal mesenchyme at both E16.5 and E18.5, whereas the GAGα-specific VCAN-V2 isoform was only localized to the smooth muscle surrounding proximal airways. Both Vcan-V1 mRNA and protein levels were strongly overexpressed in the GRmesKO lung at E18.5. Finally, we investigated the GC regulation of the ECM protease ADAMTS 12 and showed that Adamts 12 mRNA levels were markedly reduced at E18.5 in GRmesKO fetal mouse lung and were strongly induced by both cortisol and betamethasone in cultures of primary rat fetal lung fibroblasts. ADAMTS12 protein immunoreactivity was also strongly increased in the distal lung at E18.5, after dexamethasone treatment in utero. In summary, glucocorticoid signaling via GR represses GAGß domain-containing VCAN isoforms in distal lung mesenchyme in vivo by repressing Vcan gene expression and, in part, by inducing the ECM protease ADAMTS12, thereby contributing to the control of ECM remodelling and lung cell proliferation prior to birth.


Asunto(s)
Glucocorticoides/farmacología , Pulmón/efectos de los fármacos , Pulmón/embriología , Versicanos/genética , Animales , Animales Recién Nacidos , Células Cultivadas , Embrión de Mamíferos , Matriz Extracelular/efectos de los fármacos , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Femenino , Feto/efectos de los fármacos , Feto/metabolismo , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Glucocorticoides/metabolismo , Pulmón/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Embarazo , Ratas , Ratas Sprague-Dawley , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/fisiología , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Versicanos/metabolismo
9.
Semin Fetal Neonatal Med ; 24(3): 170-175, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31147162

RESUMEN

Steroids are complex lipophilic molecules that have many actions in the body to regulate cellular, tissue and organ functions across the life-span. Steroid hormones such as cortisol, aldosterone, estradiol and testosterone are synthesised from cholesterol in specialised endocrine cells in the adrenal gland, ovary and testis, and released into the circulation when required. Steroid hormones move freely into cells to activate intracellular nuclear receptors that function as multi-domain ligand-dependent transcriptional regulators in the cell nucleus. Activated nuclear receptors modify expression of hundreds to thousands of specific target genes in the genome. Steroid hormone actions in the fetus include developmental roles in the respiratory system, brain, and cardiovascular system. The synthetic glucocorticoid steroid betamethasone is used antenatally to reduce the complications of preterm birth. Development of novel selective partial glucocorticoid receptor agonists may provide improved therapies to treat the respiratory complications of preterm birth and spare the deleterious effects of postnatal glucocorticoids in other organs.


Asunto(s)
Esteroides/fisiología , Desarrollo Fetal/fisiología , Glucocorticoides/farmacología , Humanos , Pulmón/efectos de los fármacos , Pulmón/embriología , Receptores Citoplasmáticos y Nucleares/fisiología , Receptores de Esteroides/fisiología , Transducción de Señal/fisiología , Esteroides/biosíntesis
10.
Endocrinology ; 160(8): 1868-1884, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31107524

RESUMEN

Preterm birth is characterized by severe lung immaturity that is frequently treated antenatally or postnatally with the synthetic steroid betamethasone. The underlying cellular targets and pathways stimulated by betamethasone in the fetal lung are poorly defined. In this study, betamethasone was compared with corticosterone in steroid-treated primary cultures of fetal rat lung fibroblasts stimulated for 6 hours and analyzed by whole-cell transcriptome sequencing and glucocorticoid (GC) receptor (GR) chromatin immunoprecipitation sequencing (ChIP-Seq) analysis. Strikingly, betamethasone stimulated a much stronger transcriptional response compared with corticosterone for both induced and repressed genes. A total of 483 genes were significantly stimulated by betamethasone or corticosterone, with 476 stimulated by both steroids, indicating a strong overlap in regulation. Changes in mRNA levels were confirmed by quantitative PCR for eight induced and repressed target genes. Pathway analysis identified cell proliferation and cytoskeletal/cell matrix remodeling pathways as key processes regulated by both steroids. One target, transglutaminase 2 (Tgm2), was localized to fetal lung mesenchymal cells. Tgm2 mRNA and protein levels were strongly increased in fibroblasts by both steroids. Whole-genome GR ChIP-Seq analysis with betamethasone identified GC response element-binding sites close to the previously characterized GR target genes Per1, Dusp1, Fkbp5, and Sgk1 and near the genes identified by transcriptome sequencing encoding Crispld2, Tgm2, Hif3α, and Kdr, defining direct genomic induction of expression in fetal lung fibroblasts via the GR. These results demonstrate that betamethasone stimulates specific genes and cellular pathways controlling cell proliferation and extracellular matrix remodeling in lung mesenchymal fibroblasts, providing a basis for betamethasone's treatment efficacy in preterm birth.


Asunto(s)
Betametasona/farmacología , Fibroblastos/efectos de los fármacos , Pulmón/efectos de los fármacos , Mesodermo/efectos de los fármacos , Animales , Proliferación Celular/efectos de los fármacos , Corticosterona/farmacología , Femenino , Perfilación de la Expresión Génica , Pulmón/citología , Pulmón/metabolismo , Sistema de Señalización de MAP Quinasas , Proteína Glutamina Gamma Glutamiltransferasa 2 , Ratas , Ratas Sprague-Dawley , Receptores de Glucocorticoides/fisiología , Transducción de Señal , Transglutaminasas/análisis
11.
Respir Res ; 19(1): 155, 2018 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-30126423

RESUMEN

BACKGROUND: Prenatal glucocorticoid treatment decreases alveolar tissue volumes and facilitates fetal lung maturation, however the mechanisms responsible are largely unknown. This study examines whether changes in versican levels or sulphation patterns of chondroitin sulphate (CS) side chains, are associated with glucocorticoid-induced reductions in peri-alveolar tissue volumes. METHODS: Lung tissue was collected from 1) fetal sheep at 131 ± 0.1 days gestational age (GA) infused with cortisol (122-131d GA) to prematurely induce a pre-parturient-like rise in circulating cortisol, 2) fetal sheep at 143d GA bilaterally adrenalectomised (ADX) at 112d GA to remove endogenous cortisol and 3) fetal sheep at 124d GA in which bolus doses (2 × 11.4 mg) of betamethasone were administered to the pregnant ewe. The level and distribution of versican and CS glycosaminoglycans (GAG) were determined using immunohistochemistry (IHC). Fluorophore assisted carbohydrate electrophoresis (FACE) was used to determine changes in CS sulphation patterns. RESULTS: Cortisol infusion significantly decreased chondrotin-6-sulphate levels (C-6-S) to 16.4 ± 0.7 AU, compared with saline-infused fetuses (18.9 ± 0.7 AU: p = 0.04) but did not significantly alter the level of versican or chondroitin-4-sulphate (C-4-S). ADX significantly increased the level of C-4-S (28.2 ± 2.2 AU), compared with sham-operated fetuses (17.8 ± 2.0 AU; p = 0.006) without altering versican or C-6-S levels. Betamethasone significantly decreased versican, C-4-S and C-6-S in the fetal sheep lung (19.2 ± 0.9 AU, 24.9 ± 1.4 AU and 23.2 ± 1.0 AU, respectively), compared with saline-exposed fetuses (24.3 ± 0.4 AU, p = 0.0004; 33.3±0.6 AU, p = 0.0003; 29.8±1.3 AU, 0.03, respectively). CONCLUSIONS: These results indicate that glucocorticoids alter versican levels and CS side chain microstructure in alveolar lung tissue. Betamethasone appears to have a greater impact on versican and CS side chains than cortisol.


Asunto(s)
Sulfatos de Condroitina/biosíntesis , Desarrollo Fetal/fisiología , Glucocorticoides/farmacología , Pulmón/metabolismo , Proteoglicanos/biosíntesis , Versicanos/biosíntesis , Animales , Femenino , Desarrollo Fetal/efectos de los fármacos , Feto , Pulmón/efectos de los fármacos , Pulmón/crecimiento & desarrollo , Embarazo , Ovinos
12.
Sci Rep ; 7(1): 16323, 2017 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-29176597

RESUMEN

Cigarette smoking is undoubtedly a risk factor for lung cancer. Moreover, smokers with genetic mutations on chromosome 3p21.3, a region frequently deleted in cancer and notably in lung cancer, have a dramatically higher risk of aggressive lung cancer. The RNA binding motif 5 (RBM5) is one of the component genes in the 3p21.3 tumour suppressor region. Studies using human cancer specimens and cell lines suggest a role for RBM5 as a tumour suppressor. Here we demonstrate, for the first time, an in vivo role for RBM5 as a tumour suppressor in the mouse lung. We generated Rbm5 loss-of-function mice and exposed them to a tobacco carcinogen NNK. Upon exposure to NNK, Rbm5 loss-of-function mice developed lung cancer at similar rates to wild type mice. As tumourigenesis progressed, however, reduced Rbm5 expression lead to significantly more aggressive lung cancer i.e. increased adenocarcinoma nodule numbers and tumour size. Our data provide in vivo evidence that reduced RBM5 function, as occurs in a large number of patients, coupled with exposure to tobacco carcinogens is a risk factor for an aggressive lung cancer phenotype. These data suggest that RBM5 loss-of-function likely underpins at least part of the pro-tumourigenic consequences of 3p21.3 deletion in humans.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Proteínas de Unión al ADN/metabolismo , Neoplasias Pulmonares/metabolismo , Pulmón/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Animales , Proteínas de Ciclo Celular/genética , Proteínas de Unión al ADN/genética , Genes Supresores de Tumor/fisiología , Humanos , Pulmón/patología , Neoplasias Pulmonares/patología , Masculino , Ratones , Proteínas de Unión al ARN/genética , Proteínas Supresoras de Tumor/genética
13.
Stem Cells Transl Med ; 6(12): 2094-2105, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29027762

RESUMEN

Treatment of preterm human infants with high oxygen can result in disrupted lung alveolar and vascular development. Local or systemic administration of endothelial progenitor cells (EPCs) is reported to remedy such disruption in animal models. In this study, the effects of both fresh (enriched for KDR) and cultured bone marrow (BM)-derived cell populations with EPC characteristics were examined following hyperoxia in neonatal mouse lungs. Intraperitoneal injection of fresh EPCs into five-day-old mice treated with 90% oxygen resulted in full recovery of hyperoxia-induced alveolar disruption by 56 days of age. Partial recovery in septal number following hyperoxia was observed following injection of short-term cultured EPCs, yet aberrant tissue growths appeared following injection of long-term cultured cells. Fresh and long-term cultured cells had no impact on blood vessel development. Short-term cultured cells increased blood vessel number in normoxic and hyperoxic mice by 28 days but had no impact on day 56. Injection of fresh EPCs into normoxic mice significantly reduced alveolarization compared with phosphate buffered saline-injected normoxic controls. These results indicate that fresh BM EPCs have a higher and safer corrective profile in a hyperoxia-induced lung injury model compared with cultured BM EPCs but may be detrimental to the normoxic lung. The appearance of aberrant tissue growths and other side effects following injection of cultured EPCs warrants further investigation. Stem Cells Translational Medicine 2017;6:2094-2105.


Asunto(s)
Displasia Broncopulmonar/terapia , Células Progenitoras Endoteliales/trasplante , Hiperoxia/terapia , Animales , Displasia Broncopulmonar/etiología , Células Cultivadas , Células Progenitoras Endoteliales/citología , Hiperoxia/complicaciones , Inyecciones Intraperitoneales , Pulmón/irrigación sanguínea , Ratones , Ratones Endogámicos C57BL , Neovascularización Fisiológica
14.
Endocr Connect ; 6(7): 489-499, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28871060

RESUMEN

Steroid hormones play clinically important and specific regulatory roles in the development, growth, metabolism, reproduction and brain function in human. The type 1 and 2 11-beta hydroxysteroid dehydrogenase enzymes (11ß-HSD1 and 2) have key roles in the pre-receptor modification of glucocorticoids allowing aldosterone regulation of blood pressure, control of systemic fluid and electrolyte homeostasis and modulation of integrated metabolism and brain function. Although the activity and function of 11ß-HSDs is thought to be understood, there exists an open reading frame for a distinct 11ßHSD-like gene; HSD11B1L, which is present in human, non-human primate, sheep, pig and many other higher organisms, whereas an orthologue is absent in the genomes of mouse, rat and rabbit. We have now characterised this novel HSD11B1L gene as encoded by 9 exons and analysis of EST library transcripts indicated the use of two alternate ATG start sites in exons 2 and 3, and alternate splicing in exon 9. Relatively strong HSD11B1L gene expression was detected in human, non-human primate and sheep tissue samples from the brain, ovary and testis. Analysis in non-human primates and sheep by immunohistochemistry localised HSD11B1L protein to the cytoplasm of ovarian granulosa cells, testis Leydig cells, and gonadatroph cells in the anterior pituitary. Intracellular localisation analysis in transfected human HEK293 cells showed HSD1L protein within the endoplasmic reticulum and sequence analysis suggests that similar to 11ßHSD1 it is membrane bound. The endogenous substrate of this third HSD enzyme remains elusive with localisation and expression data suggesting a reproductive hormone as a likely substrate.

15.
J Endocrinol ; 234(1): T83-T92, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28550025

RESUMEN

The mineralocorticoid receptor (MR) mediates the actions of two important adrenal corticosteroid hormones, aldosterone and cortisol. The cell signalling roles of the MR in vivo have expanded enormously since the cloning of human MR gene 30 years ago and the first MR gene knockout in mice nearly 20 years ago. Complete ablation of the MR revealed important roles postnatally for regulation of kidney epithelial functions, with MR-null mice dying 1-2 weeks postnatally from renal salt wasting and hyperkalaemia, with elevated plasma renin and aldosterone. Generation of tissue-selective MR-deficient mice using Cre recombinase-LoxP gene targeting has made it possible to analyse mice lacking MR only in specific cell types. Targeting renal-specific MR has differentiated roles in specific compartments of the kidney. Ablating MR in neurons of the forebrain reinforced important roles of the MR in response to stress, behaviour and anxiety, but suggested a minimal role in maintaining basal HPA axis tone. Deletion of the MR in macrophages and other cell types of the cardiovascular system clearly defined important roles for the regulation of cardiovascular physiology and pathophysiology. Knockdown of MR mRNA in vivo using antisense/siRNA approaches, and similarly MR overexpression, has provided useful rodent models to study physiological roles of MR signalling in vivo More recently, targeted mutation of specific domains of the MR such as the DBD has defined genomic vs non-genomic roles in vivo New tissue-selective MR-null models are required to define roles of MR signalling in other regions of the brain, the eye, gastrointestinal tract, lung, skin, breast and gonadal organs.


Asunto(s)
Regulación de la Expresión Génica/fisiología , Receptores de Mineralocorticoides/metabolismo , Animales , Riñón/citología , Ratones , Ratones Noqueados , Receptores de Mineralocorticoides/genética
16.
Sci Rep ; 6: 22615, 2016 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-26936335

RESUMEN

Cetaceans are protected worldwide but vulnerable to incidental harm from an expanding array of human activities at sea. Managing potential hazards to these highly-mobile populations increasingly requires a detailed understanding of their seasonal distributions and habitats. Pursuant to the urgent need for this knowledge for the U.S. Atlantic and Gulf of Mexico, we integrated 23 years of aerial and shipboard cetacean surveys, linked them to environmental covariates obtained from remote sensing and ocean models, and built habitat-based density models for 26 species and 3 multi-species guilds using distance sampling methodology. In the Atlantic, for 11 well-known species, model predictions resembled seasonal movement patterns previously suggested in the literature. For these we produced monthly mean density maps. For lesser-known taxa, and in the Gulf of Mexico, where seasonal movements were less well described, we produced year-round mean density maps. The results revealed high regional differences in small delphinoid densities, confirmed the importance of the continental slope to large delphinoids and of canyons and seamounts to beaked and sperm whales, and quantified seasonal shifts in the densities of migratory baleen whales. The density maps, freely available online, are the first for these regions to be published in the peer-reviewed literature.


Asunto(s)
Biodiversidad , Cetáceos/fisiología , Modelos Biológicos , Animales , Océano Atlántico , Golfo de México , Humanos
17.
Endocrinology ; 156(8): 2958-68, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26066075

RESUMEN

The classic role of mineralocorticoid receptor (MR) is to promote sodium transport in epithelial tissues. However, the MR is also expressed in a range of tissues in which its role appears unrelated to sodium transport, and under normal physiological conditions, it may be responding to cortisol (corticosterone in rodents) rather than aldosterone. The relative importance of transcriptional mechanisms such as classical genomic signaling via a hormone response element, transrepression of other transcription factors, and nongenomic signaling is not clear, particularly in nonepithelial tissues. The goal of the present study was to define the role of the different signaling pathways for the MR by separating the functional role of classic genomic signaling, mediated by DNA binding, from these two other mechanisms. We used gene targeting to generate mice in which serine is substituted for cysteine at codon 603 in the MR; this mutation precludes DNA binding. These MR C603S mutant mice either die at birth or fail to thrive, lose weight, and die between days 10 and 13 in a manner similar to that observed previously for mice null for the MR gene. Renal expression and cellular localization of MR C603S by immunohistochemistry was equivalent to control mice. MR C603S mice were rescued by twice-daily saline injections. Despite increased aldosterone levels, renal expression of aldosterone-induced genes was not increased. This unique mouse model demonstrates that DNA binding is essential for the epithelial MR response and will provide the basis for analysis of nonclassical signaling of the MR in nonepithelial tissues.


Asunto(s)
Aldosterona/farmacología , ADN/metabolismo , Riñón/efectos de los fármacos , Riñón/metabolismo , Receptores de Mineralocorticoides/metabolismo , Sodio/metabolismo , Secuencia de Aminoácidos , Animales , Regulación de la Expresión Génica/efectos de los fármacos , Técnicas de Sustitución del Gen , Transporte Iónico/efectos de los fármacos , Transporte Iónico/genética , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Mutación Missense , Unión Proteica/efectos de los fármacos , Dominios y Motivos de Interacción de Proteínas/genética , Receptores de Mineralocorticoides/genética , Dedos de Zinc/genética
18.
PeerJ ; 3: e866, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25861555

RESUMEN

In 1998, the United States sought and received International Maritime Organization-endorsement of two Mandatory Ship Reporting (MSR) systems designed to improve mariner awareness about averting ship collisions with the endangered North Atlantic right whale (Eubalaena glacialis). Vessel collisions are a serious threat to the right whale and the program was among the first formal attempts to reduce this threat. Under the provisions of the MSR, all ships >300 gross tons are required to report their location, speed, and destination to a shore-based station when entering two key right whale habitats: one in waters off New England and one off coastal Georgia and Florida. In return, reporting ships receive an automatically-generated message, delivered directly to the ship's bridge, that provides information about right whale vulnerability to vessel collisions and actions mariners can take to avoid collisions. The MSR has been in operation continuously from July 1999 to the present. Archived incoming reports provided a 15-plus year history of ship operations in these two locations. We analyzed a total of 26,772 incoming MSR messages logged between July 1999 and December 2013. Most ships that were required to report did so, and compliance rates were generally constant throughout the study period. Self-reported vessel speeds when entering the systems indicated that most ships travelled between 10 and 16 (range = 5-20 +) knots. Ship speeds generally decreased in 2009 to 2013 following implementation of vessel speed restrictions. The number of reports into the southern system remained relatively constant following a steady increase through 2007, but numbers in the northern system decreased annually beginning in 2008. If reporting is indicative of long-term patterns in shipping operations, it reflects noteworthy changes in marine transportation. Observed declines in ship traffic are likely attributable to the 2008-2009 economic recession, the containerized shipping industry making increased use of larger ships that made fewer trips, and diminished oil/gas US imports as previously inaccessible domestic deposits were exploited. Recent declines in shipping activity likely resulted in lowered collision risks for right whales and reduced their exposure to underwater noise from ships.

19.
Mol Endocrinol ; 29(2): 158-71, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25535891

RESUMEN

Glucocorticoid (GC) steroid hormones have well-characterized roles in the regulation of systemic homeostasis, yet less understood is their known role in utero to mature the developing respiratory system in preparation for birth. During late gestation, endogenously produced GCs thin the interstitial tissue of the lung, causing the vasculature and future airspaces to come into close alignment, allowing for efficient gas exchange at birth. More potent synthetic GCs are also used worldwide to reduce the severity of respiratory distress suffered by preterm infants; however, their clinical benefits are somewhat offset by potential detrimental long-term effects on health and development. Here, we review the recent literature studying both global and conditional gene-targeted respiratory mouse models of either GC deficiency or glucocorticoid receptor ablation. Although some discrepancies exist between these transgenic mouse strains, these models have revealed specific roles for GCs in particular tissue compartments of the developing lung and identify the mesenchyme as the critical site for glucocorticoid receptor-mediated lung maturation, particularly for the inhibition of cell proliferation and epithelial cell differentiation. Specific mesenchymal and epithelial cell-expressed gene targets that may potentially mediate the effect of GCs have also been identified in these studies and imply a GC-regulated system of cross talk between compartments during lung development. A better understanding of the specific roles of GCs in specific cell types and compartments of the fetal lung will allow the development of a new generation of selective GC ligands, enabling better therapeutic treatments with fewer side effects for lung immaturity at birth in preterm infants.


Asunto(s)
Glucocorticoides/metabolismo , Pulmón/crecimiento & desarrollo , Pulmón/metabolismo , Receptores de Glucocorticoides/deficiencia , Animales , Modelos Animales de Enfermedad , Ratones Noqueados , Receptores de Glucocorticoides/metabolismo , Respiración , Transducción de Señal
20.
Dev Dyn ; 244(2): 99-109, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25523132

RESUMEN

BACKGROUND: Trop2 was first discovered as a biomarker of invasive trophoblast cells. Since then most research has focused on its role in tumourigenesis because it is highly expressed in the vast majority of human tumours and animal models of cancer. It is also highly expressed in stem cells and in many organs during development. RESULTS: We review the multifaceted role of Trop2 during development and tumourigenesis, including its role in regulating cell proliferation and migration, self-renewal, and maintenance of basement membrane integrity. We discuss the evolution of Trop2 and its related protein Epcam (Trop1), including their distinct roles. Mutation of Trop2 leads to gelatinous drop-like corneal dystrophy, whereas over-expression of Trop2 in human tumours promotes tumour aggressiveness and increases mortality. Although Trop2 expression is sufficient to promote tumour growth, the surprising discovery that Trop2-null mice have an increased risk of tumour development has highlighted the complexity of Trop2 signaling. Recently, studies have begun to identify the mechanisms underlying TROP2's functions, including regulated intramembrane proteolysis or specific interactions with integrin b1 and claudin proteins. CONCLUSIONS: Understanding the mechanisms underlying TROP2 signaling will clarify its role during development, aid in the development of better cancer treatments and unlock a promising new direction in regenerative medicine.


Asunto(s)
Antígenos de Neoplasias/metabolismo , Moléculas de Adhesión Celular/metabolismo , Distrofias Hereditarias de la Córnea/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Experimentales/metabolismo , Transducción de Señal/genética , Animales , Antígenos de Neoplasias/genética , Moléculas de Adhesión Celular/genética , Movimiento Celular/genética , Proliferación Celular/genética , Conexinas/genética , Conexinas/metabolismo , Distrofias Hereditarias de la Córnea/genética , Humanos , Ratones , Proteínas de Neoplasias/genética , Neoplasias Experimentales/genética , Proteína beta1 de Unión Comunicante
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