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1.
J Endocrinol ; 247(2): R45-R62, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32966970

RESUMO

Coronavirus disease (COVID-19) is caused by a new strain of coronavirus, the severe acute respiratory syndrome coronavirus 2 or SARS-CoV-2. At the time of writing, SARS-CoV-2 has infected over 5 million people worldwide. A key step in understanding the pathobiology of the SARS-CoV-2 was the identification of -converting enzyme 2 (ACE2) as the receptor for SARS-CoV-2 to gain entry into host cells. ACE2 is an established component of the 'protective arm' of the renin-angiotensin-aldosterone-system (RAAS) that opposes ACE/angiotensin II (ANG II) pressor and tissue remodelling actions. Identification of ACE2 as the entry point for SARS-CoV-2 into cells quickly focused attention on the use of ACE inhibitors (ACEi), angiotensin receptor blockers (ARB) and mineralocorticoid receptor antagonists (MRA) in patients with hypertension and cardiovascular disease given that these pharmacological agents upregulate ACE2 expression in target cells. ACE2 is cleaved from the cells by metalloproteases ADAM10 and ADAM17. Steroid hormone receptors regulate multiple components of the RAAS and may contribute to the observed variation in the incidence of severe COVID-19 between men and women, and in patients with pre-existing endocrine-related disease. Moreover, glucocorticoids play a critical role in the acute and chronic management of inflammatory disease, independent of any effect on RAAS activity. Dexamethasone, a synthetic glucocorticoid, has emerged as a life-saving treatment in severe COVID-19. This review will examine the endocrine mechanisms that control ACE2 and discusses the impact of therapies targeting the RAAS, glucocorticoid and other endocrine systems for their relevance to the impact of SARS-CoV-2 infection and the treatment and recovery from COVID-19-related critical illness.


Assuntos
Aldosterona/metabolismo , Betacoronavirus/fisiologia , Infecções por Coronavirus/enzimologia , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/enzimologia , Sistema Renina-Angiotensina , Esteroides/metabolismo , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Animais , Betacoronavirus/genética , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/virologia , Humanos , Pandemias , Peptidil Dipeptidase A/genética , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/metabolismo , Pneumonia Viral/virologia , Receptores de Esteroides/genética , Receptores de Esteroides/metabolismo
2.
Arch Environ Contam Toxicol ; 79(2): 258-269, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32666217

RESUMO

Phenothiazine (PTZ) is a heterocyclic thiazine compound used for industrial and medical purposes. Through environmental surveillance studies, PTZ was found being discharged into a local river in Connecticut. Phenothiazine has been shown to act similarly to endocrine disrupting chemicals. This study sought to identify sex specific hormone receptor changes in Fundulus heteroclitus in response to PTZ exposure. Fundulus heteroclitus, also known as mummichog, are small fish native to the Atlantic coast of the United States and Canada. They reside in brackish waters and can survive harsh toxic environments. This model organism is native to the polluted waters found in Connecticut. In this study, fish were exposed to PTZ concentrations of 0.5 ppm, 1.0 ppm, and 2.0 ppm for 1 week. Following exposure, brain, liver, and gonad tissues were harvested; cDNA was synthesized; and mRNA expression was assessed for 6 different hormone receptors. Compared with vehicle control (ethanol) differences in mRNA expression, levels of hormone receptors were observed in various tissues from male and female fish. Many of the tissues assessed showed changes in expression level, while only female liver and testis showed no change. These results implicate PTZ as a potential endocrine disrupting compound to mummichog at environmentally relevant concentrations.


Assuntos
Fundulidae/fisiologia , Fenotiazinas/toxicidade , Receptores de Esteroides/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Canadá , Disruptores Endócrinos/metabolismo , Monitoramento Ambiental , Feminino , Fundulidae/metabolismo , Fígado/química , Masculino , Fenotiazinas/metabolismo , Testículo/efeitos dos fármacos , Poluentes Químicos da Água/análise
3.
Nature ; 584(7821): 415-419, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32641829

RESUMO

Sexual dimorphism arises from genetic differences between male and female cells, and from systemic hormonal differences1-3. How sex hormones affect non-reproductive organs is poorly understood, yet highly relevant to health given the sex-biased incidence of many diseases4. Here we report that steroid signalling in Drosophila from the ovaries to the gut promotes growth of the intestine specifically in mated females, and enhances their reproductive output. The active ovaries of the fly produce the steroid hormone ecdysone, which stimulates the division and expansion of intestinal stem cells in two distinct proliferative phases via the steroid receptors EcR and Usp and their downstream targets Broad, Eip75B and Hr3. Although ecdysone-dependent growth of the female gut augments fecundity, the more active and more numerous intestinal stem cells also increase female susceptibility to age-dependent gut dysplasia and tumorigenesis, thus potentially reducing lifespan. This work highlights the trade-offs in fitness traits that occur when inter-organ signalling alters stem-cell behaviour to optimize organ size.


Assuntos
Drosophila melanogaster/metabolismo , Fertilidade/fisiologia , Intestinos/crescimento & desenvolvimento , Longevidade/fisiologia , Tamanho do Órgão/fisiologia , Ovário/metabolismo , Esteroides/metabolismo , Envelhecimento , Animais , Carcinogênese , Proliferação de Células , Copulação/fisiologia , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/anatomia & histologia , Drosophila melanogaster/citologia , Drosophila melanogaster/fisiologia , Ecdisona/metabolismo , Feminino , Mucosa Intestinal/anatomia & histologia , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Intestinos/anatomia & histologia , Intestinos/citologia , Intestinos/patologia , Masculino , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de Esteroides/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Fatores de Transcrição/metabolismo
4.
J Ayub Med Coll Abbottabad ; 32(2): 160-164, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32583986

RESUMO

BACKGROUND: The objective of the study is to analyze the expression of androgen, estrogen and progesterone receptor in different types of endometrial carcinomas and to correlate the androgen receptor expression with estrogen and progesterone receptor and the clinicopathological parameters like lymphovascular invasion, grade of the tumour, size of tumour and extent of myometrial invasion.. METHODS: It is a cross-sectional analytical study design with a simple random sample of a total of 54 cases of different types of endometrial carcinomas from the year 2017. Immunohistochemical stains androgen receptor, estrogen receptor, and Progesterone receptor were applied in all the cases. The Pearson Chi-square test of independence was applied to measure association and P-value is calculated to check the significance of the results. RESULTS: Androgen receptor expression was observed in 73% of low-grade endometrioid carcinomas, 62.5% of high-grade endometrioid carcinomas, 62% of serous, 20% of clear cell and 18% of carcinosarcomas, respectively. Androgen positive tumours were also positive for estrogen and progesterone in most of the cases, except 3 serous carcinomas and one low-grade endometrioid carcinoma. However, no significant relation was observed between androgen expression and prognostic parameters like the lymphovascular invasion, size of the tumour and myometrial invasion. CONCLUSIONS: Maximum expression of androgen receptor was observed in endometrioid and serous carcinomas, while carcinosarcomas and clear cell carcinomas showed minimum expression with no significant correlation between androgen receptor expression and clinicopathological parameters.


Assuntos
Neoplasias do Endométrio , Receptores de Esteroides , Carcinoma Endometrioide , Estudos Transversais , Neoplasias do Endométrio/química , Neoplasias do Endométrio/epidemiologia , Neoplasias do Endométrio/metabolismo , Neoplasias do Endométrio/patologia , Feminino , Humanos , Receptores de Esteroides/análise , Receptores de Esteroides/metabolismo
8.
Med Sci (Paris) ; 36(2): 130-136, 2020 Feb.
Artigo em Francês | MEDLINE | ID: mdl-32129748

RESUMO

Cholesterol is synthesized in the endoplasmic reticulum (RE) and then transported to cellular compartments whose functions require high cholesterol levels. Here, we describe the mechanism by which cholesterol is transported from the RE to the trans-Golgi network (TGN) by the protein OSBP (Oxysterol-Binding Protein). OSBP has two complementary activities. First, it tethers the RE to the TGN by forming a contact site where the two membranes are about twenty nanometers away. Then, it exchanges RE cholesterol for a TGN lipid, phosphatidylinositol 4-phosphate (PI4P). Eventually, PI4P is hydrolyzed at the RE, making the exchange cycle irreversible. Thus, OSBP is at the center of a lipid exchange market where a transported cholesterol "costs" a PI4P. Antiviral or anti-cancer molecules target OSBP, suggesting the importance of the OSBP cycle in different physiopathological contexts. The general principles of this cycle are shared by other lipid-transfer proteins.


Assuntos
Colesterol/metabolismo , Metabolismo dos Lipídeos/fisiologia , Receptores de Esteroides/metabolismo , Animais , Transporte Biológico , Retículo Endoplasmático/metabolismo , Humanos , Fosfatos de Fosfatidilinositol/metabolismo , Receptores de Esteroides/fisiologia
9.
Gen Comp Endocrinol ; 291: 113434, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32057911

RESUMO

The extreme climatic conditions (ECCs) of the Qinghai-Tibet Plateau impose strong selective pressures on the evolution of phenotypic traits in free-living animals. It is not well understood how animals on the Qinghai-Tibet Plateau modify their adrenocortical functions in response to both predictable and unpredictable events of ECCs, especially when the available resources are lowest during the wintering life-history stage. To uncover potential physiological mechanisms, we studied the life history stage dependent features of morphology, the plasma corticosterone response to acute stress and brain glucocorticoid receptor (GR) and mineralocorticoid receptor (MR) mRNA expression in two sympatric snow finches: the white-rumped snow finch (Onychostruthus taczanowskii, WRSF); and the rufous-necked snow finch, Pyrgilauda ruficollis, RNSF) in Qinghai Province, China. Our results showed that (a) baseline corticosterone and stressor-induced corticosterone levels significantly varied with life history stage, but not between the species; (b) in WRSF, GR mRNA expression in the paraventricular nucleus was higher in the wintering stage compared to the pre-basic molt stage. There were no differences in hippocampus MR mRNA expression between stages in either species; (c) in the wintering stage, the suppression of corticosterone secretion in both species was an unexpected strategy in free-living animals. Both convergent and divergent phenotypic traits of adrenocortical responses to acute stress in two sympatric snow finches contribute to our understanding of the coping mechanisms of closely related species in the severe winter on the Qinghai-Tibet Plateau.


Assuntos
Córtex Suprarrenal/fisiologia , Tentilhões/fisiologia , Estações do Ano , Neve , Estresse Fisiológico , Simpatria/fisiologia , Animais , Cruzamento , Corticosterona/sangue , Tentilhões/sangue , Estágios do Ciclo de Vida , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Esteroides/metabolismo , Tibet
10.
Sci Rep ; 10(1): 1866, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-32024859

RESUMO

Bile acids are endogenous ligands of nuclear receptors pregnane X (PXR) and farnesoid X (FXR). PXR and FXR regulate pathways that are impaired in inflammatory bowel disease (IBD). Decreases in PXR and FXR activity are documented in IBD; however reasons for this are unknown. We aimed to assess the effect of Crohn's disease (CD) on the plasma bile acid composition in vivo and the resultant impact on PXR and FXR activation. A cross-sectional study evaluated the plasma concentrations of 12 bile acids in addition to 4ß-hydroxycholesterol (4ßOHC), an in vivo probe of the PXR target-gene cytochrome 3A4 (CYP3A4) and the FXR target-gene, fibroblast growth factor (FGF) 19 in individuals with (n = 74) and without (n = 71) CD. An in vitro model was used to assess the impact of CD-specific changes in the plasma bile acid composition on PXR and FXR activation. Decreases in glycochenodeoxycholic acid, taurocholic acid and lithocholic acid were seen in CD with increases in glycodeoxycholic acid and glycocholic acid relative to the total plasma bile acid profile. In vitro, increasing concentrations of bile acids applied in the same ratio as seen in the study cohorts resulted in decreased activation of both PXR and FXR in the CD model. In vivo, plasma 4ßOHC (CD = 18.68 ng/ml ± 13.02 ng/ml, non-CD = 46.38 ng/ml ± 40.70 ng/ml, p ≤ 0.0001) and FGF19 (CD = 0.276 pg/L ± 0.189 pg/L, non-CD = 0.485 pg/L ± 0.42 pg/L, p = 0.0002) concentrations were lower in CD versus controls. Ultimately, CD-specific changes in the plasma bile acid composition lead to reduced activation of FXR and PXR target genes in vitro and in vivo.


Assuntos
Ácidos e Sais Biliares/metabolismo , Doença de Crohn/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de Esteroides/metabolismo , Adolescente , Adulto , Idoso , Estudos Transversais , Proteínas de Ligação a DNA/metabolismo , Feminino , Fatores de Crescimento de Fibroblastos/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Reprod Biol Endocrinol ; 18(1): 12, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32070380

RESUMO

BACKGROUND: Pregnant women have high serum concentrations of sex steroid hormones, which are major regulators of paracrine and autocrine responses for many maternal and placental functions. The main purpose of this study was to compare patients with preeclampsia and patients with uncomplicated pregnancies in terms of serum steroid hormones (estradiol [E2], progesterone [P4], dehydroepiandrosterone sulfate [DHEAS], and testosterone [T]) throughout pregnancy and the levels of cord blood and placental steroid receptors during the third trimester. METHODS: Quantitative real-time reverse transcription PCR, western blotting, and immunohistochemistry were used to determine the levels of steroid hormones in the serum and cord blood and the placental levels of estrogen receptor-α (ERα), ERß, androgen receptor (AR), and progesterone receptor (PR). RESULTS: There were 45 women in the uncomplicated pregnancy group and 30 women in the preeclampsia group. Serum levels of T were greater and serum levels of E2 were reduced in the preeclampsia group, but the two groups had similar levels of P4 and DHEAS during the third trimester. Cord blood had a decreased level of DHEAS in the preeclampsia group, but the two groups had similar levels of P4, E2, and T. The two groups had similar placental mRNA levels of ERα, ERß, AR, and PR, but the preeclampsia group had a higher level of ERß protein and a lower level of ERα protein. Immunohistochemistry indicated that the preeclampsia group had a greater level of ERß in the nucleus and cytoplasm of syncytiotrophoblasts and stromal cells. CONCLUSIONS: Women with preeclampsia had lower levels of steroid hormones, estrogen, and ERα but higher levels of T and ERß. These molecules may have roles in the pathogenesis of preeclampsia.


Assuntos
Sangue Fetal/metabolismo , Hormônios Esteroides Gonadais/metabolismo , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Receptores de Esteroides/metabolismo , Adulto , Biomarcadores/sangue , Biomarcadores/metabolismo , Sulfato de Desidroepiandrosterona/metabolismo , Estradiol/sangue , Estradiol/metabolismo , Feminino , Hormônios Esteroides Gonadais/sangue , Humanos , Pessoa de Meia-Idade , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/diagnóstico , Gravidez , Progesterona/sangue , Progesterona/metabolismo , Estudos Prospectivos , Receptores de Esteroides/sangue , Testosterona/sangue , Testosterona/metabolismo , Adulto Jovem
12.
Nat Commun ; 11(1): 470, 2020 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-31980607

RESUMO

The molecular mechanisms underlying the response to exercise and inactivity are not fully understood. We propose an innovative approach to profile the skeletal muscle transcriptome to exercise and inactivity using 66 published datasets. Data collected from human studies of aerobic and resistance exercise, including acute and chronic exercise training, were integrated using meta-analysis methods (www.metamex.eu). Here we use gene ontology and pathway analyses to reveal selective pathways activated by inactivity, aerobic versus resistance and acute versus chronic exercise training. We identify NR4A3 as one of the most exercise- and inactivity-responsive genes, and establish a role for this nuclear receptor in mediating the metabolic responses to exercise-like stimuli in vitro. The meta-analysis (MetaMEx) also highlights the differential response to exercise in individuals with metabolic impairments. MetaMEx provides the most extensive dataset of skeletal muscle transcriptional responses to different modes of exercise and an online interface to readily interrogate the database.


Assuntos
Adaptação Fisiológica/genética , Exercício Físico/fisiologia , Músculo Esquelético/fisiologia , Comportamento Sedentário , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Perfilação da Expressão Gênica , Ontologia Genética , Redes Reguladoras de Genes , Humanos , Receptores de Esteroides/genética , Receptores de Esteroides/metabolismo , Receptores dos Hormônios Tireóideos/genética , Receptores dos Hormônios Tireóideos/metabolismo , Treinamento de Resistência
13.
Dev Cell ; 52(4): 461-476.e4, 2020 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-31928972

RESUMO

Phosphoinositides, diacylglycerolpyrophosphate, ceramide-1-phosphate, and phosphatidic acid belong to a unique class of membrane signaling lipids that contain phosphomonoesters in their headgroups having pKa values in the physiological range. The phosphomonoester headgroup of phosphatidic acid enables this lipid to act as a pH biosensor as changes in its protonation state with intracellular pH regulate binding to effector proteins. Here, we demonstrate that binding of pleckstrin homology (PH) domains to phosphatidylinositol 4-phosphate (PI4P) in the yeast trans-Golgi network (TGN) is dependent on intracellular pH, indicating PI4P is a pH biosensor. pH biosensing by TGN PI4P in response to nutrient availability governs protein sorting at the TGN, likely by regulating sterol transfer to the TGN by Osh1, a member of the conserved oxysterol-binding protein (OSBP) family of lipid transfer proteins. Thus, pH biosensing by TGN PI4P allows for direct metabolic regulation of protein trafficking and cell growth.


Assuntos
Proteínas de Transporte/metabolismo , Glucose/farmacologia , Fosfatos de Fosfatidilinositol/metabolismo , Receptores de Esteroides/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Rede trans-Golgi/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Transporte Proteico , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Transdução de Sinais , Edulcorantes/farmacologia , Rede trans-Golgi/efeitos dos fármacos
14.
Biochim Biophys Acta Mol Cell Res ; 1867(2): 118603, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31733263

RESUMO

Not so long ago, contact sites between the endoplasmic reticulum (ER) and lipid droplets (LDs) were largely unexplored on a molecular level. In recent years however, numerous proteins have been identified that are enriched or exclusively located at the interfaces between LDs and the ER. These comprise members of protein classes typically found in diverse types of contacts, such as organelle tethers and lipid transfer proteins, but also proteins that have no similarities to known contact site machineries. This structurally heterogeneous group of contact site residents might be required to fulfill unique aspects of LD-ER contact biology, such as de novo LD biogenesis, and maintenance of lipidic connections between LDs and ER. Here, we summarize the current knowledge on the molecular components of this special organelle contact site, and discuss their features and functions.


Assuntos
Retículo Endoplasmático/metabolismo , Gotículas Lipídicas/metabolismo , Subunidades gama da Proteína de Ligação ao GTP/química , Subunidades gama da Proteína de Ligação ao GTP/metabolismo , Humanos , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Receptores de Esteroides/química , Receptores de Esteroides/metabolismo , Nexinas de Classificação/química , Nexinas de Classificação/metabolismo , Proteínas de Transporte Vesicular/química , Proteínas de Transporte Vesicular/metabolismo , Proteínas rab de Ligação ao GTP/química , Proteínas rab de Ligação ao GTP/metabolismo
15.
Environ Pollut ; 256: 112957, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31672375

RESUMO

Parabens are class of preservatives used in vast majority of commercial products, and a potential Endocrine Disrupting Chemical (EDC). The present study was undertaken to delineate the effects of n-butylparaben on F1 male progeny exposed maternally through gestation and lactation via subcutaneous route. The F0 dams were given subcutaneous injections of n-butylparaben from gestation day (GD) 6 to postnatal day (PND) 21 with doses of 10, 100, 1000 mg/kg Bw/day in corn oil. The F1 male rats were monitored for pubertal development and sexual maturation; these were sacrificed on PND 30, 45 and 75. On PND 75, these F1 male rats were subjected for fertility assessment with unexposed female rats. A delayed testicular descent at 100 and 1000 mg/kg Bw dose and delayed preputial separation at 10 mg/kg Bw dose was observed in exposed F1 male rats. Decreased sperm count, motility and Daily Sperm Production was observed at 100 mg/kg Bw dose at PND 75. Interestingly, the sperm transit time in the epididymis was accelerated at this dose. Significant perturbed testicular expression of steroid receptors (ERα and ß, AR), INSL3 and StAR genes with increased T and LH levels indicates direct effect on spermatogenesis and steroidogenesis. These F1 generation adult rats were sub-fertile with increased (%) pre- and post-implantation loss at 100 and 1000 mg/kg Bw/day dose. This is the first report on n-butylparaben highlighting the involvement of testicular leydig cells with accelerated sperm transit time leading to reduced fertility in the maternally exposed F1 male rats through estrogenic/anti-androgenic action.


Assuntos
Disruptores Endócrinos/toxicidade , Fertilidade/efeitos dos fármacos , Parabenos/toxicidade , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Receptores de Esteroides/metabolismo , Espermatogênese/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Lactação , Células Intersticiais do Testículo/efeitos dos fármacos , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Ratos , Receptores de Esteroides/genética , Maturidade Sexual/efeitos dos fármacos , Contagem de Espermatozoides , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testículo/embriologia , Testículo/crescimento & desenvolvimento
16.
J Cell Biol ; 219(1)2020 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-31653673

RESUMO

Lipid droplets (LDs) are evolutionarily conserved organelles that play important roles in cellular metabolism. Each LD is enclosed by a monolayer of phospholipids, distinct from bilayer membranes. During LD biogenesis and growth, this monolayer of lipids expands by acquiring phospholipids from the endoplasmic reticulum (ER) through nonvesicular mechanisms. Here, in a mini-screen, we find that ORP5, an integral membrane protein of the ER, can localize to ER-LD contact sites upon oleate loading. ORP5 interacts with LDs through its ligand-binding domain, and ORP5 deficiency enhances neutral lipid synthesis and increases the size of LDs. Importantly, there is significantly more phosphatidylinositol-4-phosphate (PI(4)P) and less phosphatidylserine (PS) on LDs in ORP5-deficient cells than in normal cells. The increased presence of PI(4)P on LDs in ORP5-deficient cells requires phosphatidylinositol 4-kinase 2-α. Our results thus demonstrate the existence of PI(4)P on LDs and suggest that LD-associated PI(4)P may be primarily used by ORP5 to deliver PS to LDs.


Assuntos
Retículo Endoplasmático/metabolismo , Gotículas Lipídicas/metabolismo , Antígenos de Histocompatibilidade Menor/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Proteínas de Transferência de Fosfolipídeos/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Receptores de Esteroides/metabolismo , Células HEK293 , Humanos , Metabolismo dos Lipídeos
17.
PLoS Genet ; 15(12): e1008491, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31809495

RESUMO

Neuronal diversity is at the core of the complex processing operated by the nervous system supporting fundamental functions such as sensory perception, motor control or memory formation. A small number of progenitors guarantee the production of this neuronal diversity, with each progenitor giving origin to different neuronal types over time. How a progenitor sequentially produces neurons of different fates and the impact of extrinsic signals conveying information about developmental progress or environmental conditions on this process represent key, but elusive questions. Each of the four progenitors of the Drosophila mushroom body (MB) sequentially gives rise to the MB neuron subtypes. The temporal fate determination pattern of MB neurons can be influenced by extrinsic cues, conveyed by the steroid hormone ecdysone. Here, we show that the activation of Transforming Growth Factor-ß (TGF-ß) signalling via glial-derived Myoglianin regulates the fate transition between the early-born α'ß' and the pioneer αß MB neurons by promoting the expression of the ecdysone receptor B1 isoform (EcR-B1). While TGF-ß signalling is required in MB neuronal progenitors to promote the expression of EcR-B1, ecdysone signalling acts postmitotically to consolidate theα'ß' MB fate. Indeed, we propose that if these signalling cascades are impaired α'ß' neurons lose their fate and convert to pioneer αß. Conversely, an intrinsic signal conducted by the zinc finger transcription factor Krüppel-homolog 1 (Kr-h1) antagonises TGF-ß signalling and acts as negative regulator of the response mediated by ecdysone in promoting α'ß' MB neuron fate consolidation. Taken together, the consolidation of α'ß' MB neuron fate requires the response of progenitors to local signalling to enable postmitotic neurons to sense a systemic signal.


Assuntos
Encéfalo/crescimento & desenvolvimento , Drosophila/crescimento & desenvolvimento , Ecdisona/metabolismo , Transdução de Sinais , Animais , Padronização Corporal , Encéfalo/metabolismo , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Fatores de Transcrição Kruppel-Like/metabolismo , Corpos Pedunculados/crescimento & desenvolvimento , Corpos Pedunculados/metabolismo , Receptores de Esteroides/metabolismo , Fator de Crescimento Transformador beta/metabolismo
18.
Reprod Biol Endocrinol ; 17(1): 111, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31878927

RESUMO

BACKGROUND: Previous studies of expression profiles of major endometrial effectors of steroid physiology in endometriosis have yielded markedly conflicting conclusions, presumably because the relative effects of type of endometriosis, fertility history and menstrual cycle phases on the measured variables were not considered. In the present study, endometrial mRNA and protein levels of several effectors of steroid biosynthesis and action in patients with stage III-IV ovarian endometriosis (OE) with known fertility and menstrual cycle histories were compared with the levels in control endometrium to test this concept. METHODS: Endometrial samples were collected from patients without endometriosis (n = 32) or OE stages III-IV (n = 52) with known fertility and cycle histories. qRT-PCR and immunoblotting experiments were performed to measure levels of NR5A1, STAR, CYP19A1, HSD17Bs, ESRs and PGR transcripts and proteins, respectively. Tissue concentrations of steroids (P4, T, E1 and E2) were measured using ELISAs. RESULTS: The levels of expression of aromatase and ERß were lower (P < 0.0001) and 17ß-HSD1 (P < 0.0001) and PRA (P < 0.01) were higher in OE endometrium. Lower aromatase levels and higher 17ß-HSD1 levels were detected in fertile (aromatase: P < 0.05; 17ß-HSD1: P < 0.0001) and infertile (aromatase: P < 0.0001; 17ß-HSD1: P < 0.0001) OE endometrium than in the matched control tissues. Both proliferative (PP) and secretory (SP) phase OE samples expressed aromatase (P < 0.0001) and ERß (PP: P < 0.001; SP: P < 0.01) at lower levels and 17ß-HSD1 (P < 0.0001) and PRA (PP: P < 0.01; SP: P < 0.0001) at higher levels than matched controls. Higher 17ß-HSD1 (P < 0.01) and E2 (P < 0.05) levels and a lower (P < 0.01) PRB/PRA ratio was observed in infertile secretory phase OE endometrium than in control. CONCLUSIONS: We report that dysregulated expression of 17ß-HSD1 and PGR resulting in hyperestrogenism and progesterone resistance during the secretory phase of the menstrual cycle, rather than an anomaly in aromatase expression, was the hallmark of eutopic endometrium from infertile OE patients. Furthermore, the results provide proof of concept that the fertility and menstrual cycle histories exerted relatively different effects on steroid physiology in the endometrium from OE patients compared with the control subjects.


Assuntos
Endometriose/metabolismo , Endométrio/metabolismo , Hormônios Esteroides Gonadais/metabolismo , Doenças Ovarianas/metabolismo , Receptores de Esteroides/metabolismo , 17-Hidroxiesteroide Desidrogenases/análise , 17-Hidroxiesteroide Desidrogenases/genética , Adolescente , Adulto , Aromatase/análise , Aromatase/genética , Endométrio/química , Estradiol/análise , Feminino , Expressão Gênica , Humanos , Infertilidade Feminina/metabolismo , Ciclo Menstrual , Progesterona/análise , Receptores Estrogênicos/análise , Receptores de Progesterona/análise , Receptores de Esteroides/genética , Adulto Jovem
19.
Biochemistry (Mosc) ; 84(11): 1306-1328, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31760920

RESUMO

Focal brain injuries (in particular, stroke and traumatic brain injury) induce with high probability the development of delayed (months, years) cognitive and depressive disturbances which are frequently comorbid. The association of these complications with hippocampal alterations (in spite of the lack of a primary injury of this structure), as well as the lack of a clear dependence between the probability of depression and dementia development and primary damage severity and localization served as the basis for a new hypothesis on the distant hippocampal damage as a key link in the pathogenesis of cognitive and psychiatric disturbances. According to this hypothesis, the excess of corticosteroids secreted after a focal brain damage, in particular in patients with abnormal stress-response due to hypothalamic-pituitary-adrenal axis (HPAA) dysfunction, interacts with corticosteroid receptors in the hippocampus inducing signaling pathways which stimulate neuroinflammation and subsequent events including disturbances in neurogenesis and hippocampal neurodegeneration. In this article, the molecular and cellular mechanisms associated with the regulatory role of the HPAA and multiple functions of brain corticosteroid receptors in the hippocampus are analyzed. Functional and structural damage to the hippocampus, a brain region selectively vulnerable to external factors and responding to them by increased cytokine secretion, forms the basis for cognitive function disturbances and psychopathology development. This concept is confirmed by our own experimental data, results of other groups and by prospective clinical studies of post-stroke complications. Clinically relevant biochemical approaches to predict the risks and probability of post-stroke/post-trauma cognitive and depressive disturbances are suggested using the evaluation of biochemical markers of patients' individual stress-response. Pathogenetically justified ways for preventing these consequences of focal brain damage are proposed by targeting key molecular mechanisms underlying hippocampal dysfunction.


Assuntos
Lesões Encefálicas/patologia , Hipocampo/metabolismo , Animais , Lesões Encefálicas/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Citocinas/metabolismo , Humanos , Estresse Oxidativo , Sistema Hipófise-Suprarrenal , Receptores de Esteroides/metabolismo
20.
PLoS Biol ; 17(10): e3000145, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31589603

RESUMO

Male reproductive glands like the mammalian prostate and the paired Drosophila melanogaster accessory glands secrete seminal fluid components that enhance fecundity. In humans, the prostate, stimulated by environmentally regulated endocrine and local androgens, grows throughout adult life. We previously showed that in fly accessory glands, secondary cells (SCs) and their nuclei also grow in adults, a process enhanced by mating and controlled by bone morphogenetic protein (BMP) signalling. Here, we demonstrate that BMP-mediated SC growth is dependent on the receptor for the developmental steroid ecdysone, whose concentration is reported to reflect sociosexual experience in adults. BMP signalling appears to regulate ecdysone receptor (EcR) levels via one or more mechanisms involving the EcR's N terminus or the RNA sequence that encodes it. Nuclear growth in virgin males is dependent on ecdysone, some of which is synthesised in SCs. However, mating induces additional BMP-mediated nuclear growth via a cell type-specific form of hormone-independent EcR signalling, which drives genome endoreplication in a subset of adult SCs. Switching to hormone-independent endoreplication after mating allows growth and secretion to be hyperactivated independently of ecdysone levels in SCs, permitting more rapid replenishment of the accessory gland luminal contents. Our data suggest mechanistic parallels between this physiological, behaviour-induced signalling switch and altered pathological signalling associated with prostate cancer progression.


Assuntos
Proteínas Morfogenéticas Ósseas/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Ecdisona/metabolismo , Genoma de Inseto , Proteínas de Insetos/genética , Receptores de Esteroides/genética , Animais , Proteínas Morfogenéticas Ósseas/metabolismo , Núcleo Celular/metabolismo , Núcleo Celular/ultraestrutura , Copulação/fisiologia , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Insetos/antagonistas & inibidores , Proteínas de Insetos/metabolismo , Masculino , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Receptores de Esteroides/antagonistas & inibidores , Receptores de Esteroides/metabolismo , Transdução de Sinais
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