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1.
Cell Mol Life Sci ; 81(1): 14, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38191696

RESUMEN

Sigma-1 receptor (S1R) is a calcium-sensitive, ligand-operated receptor chaperone present on the endoplasmic reticulum (ER) membrane. S1R plays an important role in ER-mitochondrial inter-organelle calcium signaling and cell survival. S1R and its agonists confer resilience against various neurodegenerative diseases; however, the molecular mechanism of S1R is not yet fully understood. At resting state, S1R is either in a monomeric or oligomeric state but the ratio of these concentrations seems to change upon activation of S1R. S1R is activated by either cellular stress, such as ER-calcium depletion, or ligands. While the effect of ligands on S1R quaternary structure remains unclear, the effect of cellular stress has not been studied. In this study we utilize cellular and an in-vivo model to study changes in quaternary structure of S1R upon activation. We incubated cells with cellular stressors (H2O2 and thapsigargin) or exogenous ligands, then quantified monomeric and oligomeric forms. We observed that benzomorphan-based S1R agonists induce monomerization of S1R and decrease oligomerization, which was confirmed in the liver tissue of mice injected with (+)-Pentazocine. Antagonists block this effect but do not induce any changes when used alone. Oxidative stress (H2O2) increases the monomeric/oligomeric S1R ratio whereas ER calcium depletion (thapsigargin) has no effect. We also analyzed the oligomerization ability of various truncated S1R fragments and identified the fragments favorizing oligomerization. In this publication we demonstrate that quaternary structural changes differ according to the mechanism of S1R activation. Therefore, we offer a novel perspective on S1R activation as a nuanced phenomenon dependent on the type of stimulus.


Asunto(s)
Benzomorfanos , Calcio , Animales , Ratones , Peróxido de Hidrógeno , Receptor Sigma-1 , Tapsigargina , Señalización del Calcio
2.
BMC Cancer ; 23(1): 1103, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37957624

RESUMEN

BACKGROUND: Non-gestational choriocarcinoma (NGC) is a rare subtype of malignant germ cell tumour and there is no consensus on its treatment. The lack of suitable preclinical models for NGC is a challenge in drug discovery research. Patient-derived xenograft (PDX) models recapitulate the tumour microenvironment of the original cancer tissue. Therefore, they have received considerable attention for studies on rare cancer. Here, we aimed to establish a PDX model from a patient with recurrent NGC. METHODS: Fresh NGC tumour tissue was immediately transplanted into a severely immune-deficient mouse (NOD.Cg-Prkdcscid1l2rgtm1Wjl/SzJ) and maintained for more than three in vivo passages. Subsequently, we evaluated the molecular characteristics of the PDX model using immunohistochemistry, polymerase chain reaction, and RNA sequencing. Moreover, the PDX tumours were transplanted into BALB/c nude mice, and we evaluated their sensitivity for cisplatin and methotrexate. RESULTS: The PDX tumour maintained the morphological features of NGC. Moreover, Immunohistochemistry revealed that the human chorionic gonadotropin, cytokeratin 7, and EpCAM expression levels were similar to those in the primary tumour. Furthermore, serum human chorionic gonadotropin levels were elevated in both the primary tumour and the PDX models. Additionally, using PCR analysis with species-specific primers, we confirmed that the PDX tumour contained human genes and was derived from human tissue. Moreover, the gene expression profile of the NGC was compared with that of epithelial ovarian cancer samples and cell lines, and 568 dysregulated genes in the NGC were extracted. The expression of the dysregulated genes in PDX was significantly correlated with that in the primary tumour (R2 = 0.873, P < 0.001). Finally, we demonstrated that the PDX tumour was sensitive to cisplatin and methotrexate; therefore, its clinical response to the agents was similar to that of the primary tumour. CONCLUSIONS: We successfully established a PDX model of NGC, to the best of our knowledge, for the first time. The established PDX retained the molecular and transcriptome characteristics of the primary tumour and can be used to predict drug effects. It may facilitate further research and the development of novel therapeutic agents for NGC.


Asunto(s)
Coriocarcinoma no Gestacional , Cisplatino , Femenino , Humanos , Ratones , Animales , Ensayos Antitumor por Modelo de Xenoinjerto , Metotrexato , Xenoinjertos , Ratones Desnudos , Ratones Endogámicos NOD , Modelos Animales de Enfermedad , Gonadotropina Coriónica , Ratones SCID , Microambiente Tumoral
3.
Int J Mol Sci ; 24(9)2023 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-37175473

RESUMEN

The sigma-1 receptor (SIGMAR1) is one of a kind: a receptor chaperone protein. This 223 amino acid-long protein is enriched at the mitochondria-associated endoplasmic reticulum membrane (MAM), a specialized microdomain of the endoplasmic reticulum that is structurally and functionally connected to the mitochondria. As a receptor, SIGMAR1 binds a wide spectrum of ligands. Numerous molecules targeting SIGMAR1 are currently in pre-clinical or clinical development. Interestingly, the range of pathologies covered by these studies is broad, especially with regard to neurodegenerative disorders. Upon activation, SIGMAR1 can translocate and interact with other proteins, mostly at the MAM but also in other organelles, which allows SIGMAR1 to affect many cellular functions. During these interactions, SIGMAR1 exhibits chaperone protein behavior by participating in the folding and stabilization of its partner. In this short communication, we will shed light on how SIGMAR1 confers protection against neurodegeneration to the cells of the nervous system and why this ability makes SIGMAR1 a multifunctional therapeutic prospect.


Asunto(s)
Enfermedades Neurodegenerativas , Receptores sigma , Humanos , Retículo Endoplásmico/metabolismo , Mitocondrias/metabolismo , Enfermedades Neurodegenerativas/metabolismo , Receptores sigma/metabolismo , Receptor Sigma-1
4.
Autophagy ; 19(1): 126-151, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35507432

RESUMEN

Macroautophagy/autophagy is an essential process for cellular survival and is implicated in many diseases. A critical step in autophagy is the transport of the transcription factor TFEB from the cytosol into the nucleus, through the nuclear pore (NP) by KPNB1/importinß1. In the C9orf72 subtype of amyotrophic lateral sclerosis-frontotemporal lobar degeneration (ALS-FTD), the hexanucleotide (G4C2)RNA expansion (HRE) disrupts the nucleocytoplasmic transport of TFEB, compromising autophagy. Here we show that a molecular chaperone, the SIGMAR1/Sigma-1 receptor (sigma non-opioid intracellular receptor 1), facilitates TFEB transport into the nucleus by chaperoning the NP protein (i.e., nucleoporin) POM121 which recruits KPNB1. In NSC34 cells, HRE reduces TFEB transport by interfering with the association between SIGMAR1 and POM121, resulting in reduced nuclear levels of TFEB, KPNB1, and the autophagy marker LC3-II. Overexpression of SIGMAR1 or POM121, or treatment with the highly selective and potent SIGMAR1 agonist pridopidine, currently in phase 2/3 clinical trials for ALS and Huntington disease, rescues all of these deficits. Our results implicate nucleoporin POM121 not merely as a structural nucleoporin, but also as a chaperone-operated signaling molecule enabling TFEB-mediated autophagy. Our data suggest the use of SIGMAR1 agonists, such as pridopidine, for therapeutic development of diseases in which autophagy is impaired.Abbreviations: ALS-FTD, amyotrophic lateral sclerosis-frontotemporal dementiaC9ALS-FTD, C9orf72 subtype of amyotrophic lateral sclerosis-frontotemporal dementiaCS, citrate synthaseER, endoplasmic reticulumGSS, glutathione synthetaseHRE, hexanucleotide repeat expansionHSPA5/BiP, heat shock protein 5LAMP1, lysosomal-associated membrane protein 1MAM, mitochondria-associated endoplasmic reticulum membraneMAP1LC3/LC3, microtubule-associated protein 1 light chain 3NP, nuclear poreNSC34, mouse motor neuron-like hybrid cell lineNUPs, nucleoporinsPOM121, nuclear pore membrane protein 121SIGMAR1/Sigma-1R, sigma non-opioid intracellular receptor 1TFEB, transcription factor EBTMEM97/Sigma-2R, transmembrane protein 97.


Asunto(s)
Esclerosis Amiotrófica Lateral , Autofagia , Demencia Frontotemporal , Proteínas de la Membrana , Receptores sigma , Animales , Ratones , Esclerosis Amiotrófica Lateral/metabolismo , Autofagia/genética , Proteína C9orf72/genética , Demencia Frontotemporal/genética , Proteínas de Choque Térmico/metabolismo , Proteínas de Complejo Poro Nuclear , Factores de Transcripción/metabolismo , Proteínas de la Membrana/genética , Receptores sigma/metabolismo , Receptor Sigma-1
5.
Sci Transl Med ; 14(631): eabh3763, 2022 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-35138910

RESUMEN

The Wolfram syndrome is a rare autosomal recessive disease affecting many organs with life-threatening consequences; currently, no treatment is available. The disease is caused by mutations in the WSF1 gene, coding for the protein wolframin, an endoplasmic reticulum (ER) transmembrane protein involved in contacts between ER and mitochondria termed as mitochondria-associated ER membranes (MAMs). Inherited mutations usually reduce the protein's stability, altering its homeostasis and ultimately reducing ER to mitochondria calcium ion transfer, leading to mitochondrial dysfunction and cell death. In this study, we found that activation of the sigma-1 receptor (S1R), an ER-resident protein involved in calcium ion transfer, could counteract the functional alterations of MAMs due to wolframin deficiency. The S1R agonist PRE-084 restored calcium ion transfer and mitochondrial respiration in vitro, corrected the associated increased autophagy and mitophagy, and was able to alleviate the behavioral symptoms observed in zebrafish and mouse models of the disease. Our findings provide a potential therapeutic strategy for treating Wolfram syndrome by efficiently boosting MAM function using the ligand-operated S1R chaperone. Moreover, such strategy might also be relevant for other degenerative and mitochondrial diseases involving MAM dysfunction.


Asunto(s)
Receptores sigma , Síndrome de Wolfram , Animales , Calcio/metabolismo , Femenino , Humanos , Masculino , Ratones , Receptores sigma/agonistas , Pez Cebra/metabolismo , Receptor Sigma-1
6.
Cell Mol Neurobiol ; 42(3): 597-620, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33095392

RESUMEN

Sigma-1 receptor (Sig-1R) is a protein present in several organs such as brain, lung, and heart. In a cell, Sig-1R is mainly located across the membranes of the endoplasmic reticulum and more specifically at the mitochondria-associated membranes. Despite numerous studies showing that Sig-1R could be targeted to rescue several cellular mechanisms in different pathological conditions, less is known about its fundamental relevance. In this review, we report results from various studies and focus on the importance of Sig-1R in physiological conditions by comparing Sig-1R KO mice to wild-type mice in order to investigate the fundamental functions of Sig-1R. We note that the Sig-1R deletion induces cognitive, psychiatric, and motor dysfunctions, but also alters metabolism of heart. Finally, taken together, observations from different experiments demonstrate that those dysfunctions are correlated to poor regulation of ER and mitochondria metabolism altered by stress, which could occur with aging.


Asunto(s)
Receptores sigma , Animales , Retículo Endoplásmico/metabolismo , Estrés del Retículo Endoplásmico , Ratones , Mitocondrias/metabolismo , Receptores sigma/genética , Receptores sigma/metabolismo , Receptor Sigma-1
8.
Mol Neurobiol ; 58(6): 2523-2541, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33459966

RESUMEN

Sigma-1 receptors (Sig-1Rs) are endoplasmic reticulum (ER) chaperones implicated in neuropathic pain. Here we examine if the Sig-1R may relate to neuropathic pain at the level of dorsal root ganglia (DRG). We focus on the neuronal excitability of DRG in a "spare nerve injury" (SNI) model of neuropathic pain in rats and find that Sig-1Rs likely contribute to the genesis of DRG neuronal excitability by decreasing the protein level of voltage-gated Cav2.2 as a translational inhibitor of mRNA. Specifically, during SNI, Sig-1Rs translocate from ER to the nuclear envelope via a trafficking protein Sec61ß. At the nucleus, the Sig-1R interacts with cFos and binds to the promoter of 4E-BP1, leading to an upregulation of 4E-BP1 that binds and prevents eIF4E from initiating the mRNA translation for Cav2.2. Interestingly, in Sig-1R knockout HEK cells, Cav2.2 is upregulated. In accordance with those findings, we find that intra-DRG injection of Sig-1R agonist (+)pentazocine increases frequency of action potentials via regulation of voltage-gated Ca2+ channels. Conversely, intra-DRG injection of Sig-1R antagonist BD1047 attenuates neuropathic pain. Hence, we discover that the Sig-1R chaperone causes neuropathic pain indirectly as a translational inhibitor.


Asunto(s)
Genoma , Neuralgia/genética , Receptores sigma/metabolismo , Animales , Canales de Calcio Tipo N/genética , Canales de Calcio Tipo N/metabolismo , Retículo Endoplásmico/metabolismo , Factor 4E Eucariótico de Iniciación/metabolismo , Ganglios Espinales/metabolismo , Regulación de la Expresión Génica , Células HEK293 , Humanos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Masculino , Tejido Nervioso/lesiones , Tejido Nervioso/patología , Membrana Nuclear/metabolismo , Regiones Promotoras Genéticas/genética , Biosíntesis de Proteínas , Proteínas Proto-Oncogénicas c-fos/metabolismo , Caperuzas de ARN/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas Sprague-Dawley , Receptores sigma/agonistas , Receptores sigma/genética , Canales de Translocación SEC/metabolismo , Transcripción Genética , Receptor Sigma-1
9.
Food Chem Toxicol ; 135: 110927, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31678484

RESUMEN

The present study was conducted to examine the influence of dietary canola oil (CAN) and partially-hydrogenated soybean oil (HSO) compared to soybean oil (SOY, control) on the morphology and function of testes using miniature pigs as the test subject. Male miniature pigs were fed a diet containing 10%SOY, 9%CAN+1%SOY, or 9%HSO+1%SOY for 18 months. The scheduled autopsies revealed no abnormalities in histopathological examination of the major organs, except the testes. Atrophy of the seminiferous tubules and hyperplasia in the Leydig cells were found in the SOY and CAN groups. DNA microarray analysis indicated downregulation in the CAN and the HSO groups of genes encoding for gonadotropins in the pituitary gland and of enzymes and proteins involved in steroid hormone metabolism in the testes, compared to the SOY group. Plasma levels of sex hormones in the CAN and HSO groups tended to be higher and testosterone and dihydrotestosteorne in the HSO group were significantly higher than in the SOY group. These results demonstrate that testes are morphologically and functionally affected by the dietary oils, while the plasma steroid hormone levels do not necessarily reflect the gene expression, probably owing to feedback regulation via the gonadal hormones in the hypothalamus-pituitary-gonadal axis.


Asunto(s)
Aceite de Brassica napus/toxicidad , Aceite de Soja/toxicidad , Testículo/efectos de los fármacos , Congéneres de la Testosterona/metabolismo , Animales , Peso Corporal/efectos de los fármacos , Dieta , Regulación hacia Abajo/genética , Expresión Génica/efectos de los fármacos , Masculino , Tamaño de los Órganos/efectos de los fármacos , Porcinos , Porcinos Enanos , Testículo/metabolismo
10.
Elife ; 82019 10 09.
Artículo en Inglés | MEDLINE | ID: mdl-31596232

RESUMEN

Cocaine is an addictive drug that acts in brain reward areas. Recent evidence suggests that cocaine stimulates synthesis of the endocannabinoid 2-arachidonoylglycerol (2-AG) in midbrain, increasing dopamine neuron activity via disinhibition. Although a mechanism for cocaine-stimulated 2-AG synthesis is known, our understanding of 2-AG release is limited. In NG108 cells and mouse midbrain tissue, we find that 2-AG is localized in non-synaptic extracellular vesicles (EVs) that are secreted in the presence of cocaine via interaction with the chaperone protein sigma-1 receptor (Sig-1R). The release of EVs occurs when cocaine causes dissociation of the Sig-1R from ADP-ribosylation factor (ARF6), a G-protein regulating EV trafficking, leading to activation of myosin light chain kinase (MLCK). Blockade of Sig-1R function, or inhibition of ARF6 or MLCK also prevented cocaine-induced EV release and cocaine-stimulated 2-AG-modulation of inhibitory synapses in DA neurons. Our results implicate the Sig-1R-ARF6 complex in control of EV release and demonstrate that cocaine-mediated 2-AG release can occur via EVs.


Asunto(s)
Cocaína/farmacología , Endocannabinoides/metabolismo , Vesículas Extracelulares/metabolismo , Receptores sigma/metabolismo , Transducción de Señal/efectos de los fármacos , Factor 6 de Ribosilación del ADP , Factores de Ribosilacion-ADP/metabolismo , Animales , Mesencéfalo/efectos de los fármacos , Mesencéfalo/metabolismo , Ratones , Quinasa de Cadena Ligera de Miosina/metabolismo , Receptor Sigma-1
11.
J Drug Alcohol Res ; 52016 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-27088037

RESUMEN

The sigma-1 receptor (Sig-1R) is an endoplasmic reticulum membrane protein that involves a wide range of physiological functions. The Sig-1R has been shown to bind psychostimulants including cocaine and methamphetamine (METH) and thus has been implicated in the actions of those psychostimulants. For example, it has been demonstrated that the Sig-1R antagonists mitigate certain behavioral and cellular effects of psychostimulants including hyperactivity and neurotoxicity. Thus, the Sig-1R has become a potential therapeutic target of medication development against drug abuse that differs from traditional monoamine-related strategies. In this review, we will focus on the molecular mechanisms of the Sig-1R and discuss in such a manner with a hope to further understand or unveil unexplored relations between the Sig-1R and the actions of cocaine and METH, particularly in the context of cellular biological relevance.

12.
Biomed Res ; 33(4): 217-24, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22975632

RESUMEN

Glial cells missing Drosophila homolog a (GCMa) is a member of the GCM transcription factor family and plays critical roles in trophoblast differentiation and placental functions. It is well established that the cyclic AMP (cAMP)-dependent pathway induces the expression and transcriptional activity of GCMa by regulating post-translational modifications of GCMa, which results in enhancement of trophoblast differentiation. We previously observed that phorbol 12-myristate 13-acetate (PMA) stimulates phosphorylation of GCMa on serines 328, 378 and 383 through the protein kinase C (PKC)- and mitogen-activated protein kinase kinase (MEK)/extracellular signalregulated kinase (ERK)-dependent pathway, which decreases the protein stability of GCMa. Here we report that PMA increases the ubiquitination level of GCMa, dependent on the phosphorylation of GCMa on serines 328, 378 and 383. We found that this phosphorylation also stimulates the transcriptional activity of GCMa. Our data indicate that the PMA-induced PKC- and MEK/ERKdependent pathway enhances the degradation as well as the transcriptional activity of GCMa. We also examined the impact of this signaling pathway on trophoblasts and the results suggest that the PKC- and MEK/ERK-dependent pathway is involved in the regulation of trophoblast differentiation.


Asunto(s)
Proteínas Nucleares/metabolismo , Proteolisis , Acetato de Tetradecanoilforbol/análogos & derivados , Factores de Transcripción/metabolismo , Activación Transcripcional , Diferenciación Celular , Proteínas de Unión al ADN , Ensayo de Inmunoadsorción Enzimática , Células HEK293 , Humanos , Sistema de Señalización de MAP Quinasas , Proteínas Nucleares/genética , Fosforilación , Proteína Quinasa C/metabolismo , Estabilidad Proteica , Serina/metabolismo , Acetato de Tetradecanoilforbol/farmacología , Factores de Transcripción/genética , Trofoblastos/metabolismo , Ubiquitinación
13.
Environ Health Prev Med ; 17(3): 173-82, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-21853259

RESUMEN

OBJECTIVES: Patients with nonalcoholic fatty liver disease are increasing worldwide, and preventive measures are an urgent need and primary concern today. AIM: This study aimed to develop and clarify the usefulness of the SHRSP5/Dmcr rat, derived from a stroke-prone spontaneously hypertensive rat, as a novel animal model for time-course analysis of steatohepatitis and the severe fibrosis progression often observed in the disease. METHODS: Ten-week-old male SHRSP5/Dmcr rats were divided into six groups: half were fed a high-fat and high-cholesterol-containing diet (HFC diet), and the others the control, stroke-prone (SP) diet for 2, 8, and 14 weeks. RESULTS: The HFC diet significantly increased serum transaminase and gamma glutamyl transpeptidase activities, tumor necrosis factor alpha levels, and serum and hepatic total cholesterol levels over time. In contrast, this diet decreased serum albumin, glucose, and adiponectin levels throughout or the later stage of the feeding period, but did not influence serum insulin levels. Histopathologically, the HFC diet increased microvesicular steatosis, and focal or spotty necrosis with lymphocyte infiltrations were observed in the liver at 2 weeks, macrovesicular steatosis, ballooned hepatocytes with Mallory-Denk body formation in some, and multilobular necrosis and fibrosis at 8 weeks. Interestingly, this fibrosis formed a honeycomb network at 14 weeks. These changes are very similar to those observed in patients with non-alcoholic steatohepatitis. CONCLUSIONS: SHRSP5/Dmcr rats appear to be a useful model for analyzing the time-dependent changes of HFC diet-induced steatohepatitis and fibrosis progression.


Asunto(s)
Colesterol en la Dieta/efectos adversos , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Hígado Graso/etiología , Cirrosis Hepática/etiología , Ratas Endogámicas SHR , Adiponectina/sangre , Albúminas/metabolismo , Animales , Biomarcadores/sangre , Glucemia/metabolismo , Presión Sanguínea , Colesterol/sangre , Progresión de la Enfermedad , Hígado Graso/sangre , Hígado Graso/patología , Insulina/sangre , Hígado/patología , Cirrosis Hepática/sangre , Cirrosis Hepática/patología , Masculino , Ratas , Ratas Endogámicas SHR/sangre , Ratas Endogámicas SHR/fisiología , Transaminasas/sangre , Factor de Necrosis Tumoral alfa/sangre , Aumento de Peso , gamma-Glutamiltransferasa/sangre
14.
Biochem Biophys Res Commun ; 417(4): 1127-32, 2012 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-22206674

RESUMEN

The glial cells missing a (GCMa) transcription factor plays a pivotal role in the placental development by regulating the expression of several genes in the placenta that are responsible for the proper formation of the syncytiotrophoblast. It is well known that the function of GCMa is regulated at both transcriptional and post-translational levels by the cyclic AMP (cAMP)/protein kinase A (PKA)-dependent pathway, the activation of which increases the GCMa protein level and leads to trophoblast differentiation into the syncytiotrophoblast. However, little is known about the regulatory control of GCMa by PKC-dependent signaling mechanism(s). To investigate whether GCMa is regulated by PKC-dependent pathway, we treated the human choriocarcinoma JEG-3 cells with phorbol 12-myristate 13-acetate (PMA) and studied its effect on the GCMa protein using a monoclonal anti-GCMa antibody we prepared. PMA caused a transient decrease in the endogenous GCMa protein level in JEG-3 cells that was accompanied by an increase in GCMa phosphorylation. The phosphorylation and degradation of GCMa by PMA treatment was effectively reduced by pretreatment with protein kinase C (PKC) inhibitors and a mitogen-activated protein kinase (MAPK) kinase (MEK) inhibitor, indicating a PKC- and MEK-dependent mechanism. Furthermore, we identified the serine residues 328, 378 and 383 to be the phosphorylation sites on GCMa that are involved in the PMA-induced degradation of GCMa. Our data demonstrate for the first time that GCMa is phosphorylated by the PKC- and MEK/extracellular signal-regulated kinase (ERK)-dependent mechanism, and that this phosphorylation is involved in its degradation process.


Asunto(s)
Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Proteínas Nucleares/metabolismo , Proteína Quinasa C/metabolismo , Acetato de Tetradecanoilforbol/metabolismo , Factores de Transcripción/metabolismo , Animales , Anticuerpos Monoclonales , Proteínas de Unión al ADN , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Células HEK293 , Humanos , Hibridomas , Sistema de Señalización de MAP Quinasas , Ratones , Neuropéptidos/genética , Neuropéptidos/inmunología , Neuropéptidos/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/inmunología , Fosforilación , Inhibidores de Proteínas Quinasas/farmacología , Estabilidad Proteica , Serina/genética , Serina/metabolismo , Acetato de Tetradecanoilforbol/farmacología , Factores de Transcripción/genética , Factores de Transcripción/inmunología
15.
Biochem Biophys Res Commun ; 415(1): 168-73, 2011 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-22033413

RESUMEN

Rho family GTPase-specific guanine nucleotide exchange factors of the Dbl family regulate a variety of cellular events including cytoskeletal arrangement, signal transduction, and gene expression through activation of Rho family GTPases. In this study, we show that hPEM-2 is a downstream effector of G(s) and G(q) signaling in Neuro-2a neuroblastoma cells. Co-expression with hPEM-2 and GTPase-deficient (constitutively active) mutants of Gαs (Gα(s)Q213L) or Gα(q) (Gα(q)Q209L), but not other GTPase-deficient mutants of Gα subunit and Gßγ subunits, activated serum response element (SRE)-dependent gene transcription, which is known to be induced by Rho family activation. Although a dominant negative mutant of Rac1 strongly blocks Gα(s)Q213L or Gα(q)Q209L/hPEM-2 activated SRE-dependent gene transcription, those of Cdc42 or RhoA are marginally affected. A PKA inhibitor, H-89, attenuated Gα(s)/hPEM-2-activated SRE-dependent gene transcription. And a dominant negative mutant of c-Src and an Src inhibitor attenuated Gα(q)Q209L/hPEM-2-activated SRE-dependent gene transcription. Experiments using hPEM-2 deletion mutants indicate that some regions of hPEM-2 play an important role in enhancing SRE activation by G(s) and G(q) signalings. These results reveal that G(s) and G(q) signalings regulate hPEM-2 functions through PKA and c-Src in Neuro-2a neuroblastoma cells, respectively.


Asunto(s)
Subunidades alfa de la Proteína de Unión al GTP Gq-G11/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gs/metabolismo , Factores de Intercambio de Guanina Nucleótido/metabolismo , Animales , Proteína Tirosina Quinasa CSK , Línea Celular Tumoral , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Factores de Intercambio de Guanina Nucleótido/genética , Humanos , Ratones , Proteínas Tirosina Quinasas/metabolismo , Factores de Intercambio de Guanina Nucleótido Rho , Transcripción Genética , Familia-src Quinasas
16.
Biomed Res ; 32(4): 237-45, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21878731

RESUMEN

Previously, we noted that the dietary restriction of α-linolenic acid (ALA, n-3) for 4 weeks after weaning brought about significant decreases in the BDNF content and p38 MAPK activity in the striatum of mice, but not in the other regions of the brain, compared with an ALA- and linoleic acid (LNA, n-6)-adequate diet. In this study, we examined whether a prolonged dietary manipulation induces biochemical changes in other regions of the brain as well. Mice were fed a safflower oil (SAF) diet (ALA-restricted, LNA-adequate) or a perilla oil (PER) diet (containing adequate amounts of ALA and LNA) for 8 weeks from weaning. The docosahexaenoic acid (DHA, 22:6n-3) contents and p38 MAPK activities in the cerebral cortex, striatum and hippocampus were significantly lower in the SAF group. The BDNF contents and protein kinase C (PKC) activities in the cerebral cortex as well as in the striatum, but not in the hippocampus, were significantly lower in the SAF group. These data indicate that the biochemical changes induced by the dietary restriction of ALA have a time lag in the striatum and cortex, suggesting that the signal is transmitted through decreased p38 MAPK activity and BDNF content and ultimately decreased PKC activity.


Asunto(s)
Encéfalo/anatomía & histología , Encéfalo/metabolismo , Grasas de la Dieta/metabolismo , Ácido alfa-Linolénico/metabolismo , Animales , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Ácidos Docosahexaenoicos/metabolismo , Masculino , Ratones , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Factores de Crecimiento Nervioso/metabolismo , Aceites de Plantas/administración & dosificación , Aceites de Plantas/química , Aceites de Plantas/metabolismo , Proteína Quinasa C/metabolismo , Aceite de Cártamo/administración & dosificación , Aceite de Cártamo/química , Aceite de Cártamo/metabolismo , Ácido alfa-Linolénico/administración & dosificación , Ácido alfa-Linolénico/química , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
17.
J Toxicol Sci ; 35(5): 743-7, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20930468

RESUMEN

Canola and some other types of oil unusually shorten the survival of stroke-prone spontaneously hypertensive rats (SHRSP), compared with soybean oil, perilla oil and animal fats. Since differential effects of canola and soybean oil on steroid hormone metabolism were suggested by a preliminary DNA microarray analysis as a reason for this, the steroid hormone levels in the serum and tissues of SHRSP fed different oils were investigated. The testosterone levels in the serum and the testes were found to be significantly lower in the canola oil group than in the soybean oil group, while no significant differences were detected in the corticosterone and estradiol levels in tissues. In a second experiment, it was found that hydrogenated soybean oil, with a survival-shortening activity comparable to that of canola oil, also decreased the testosterone level in testes to a similar degree. The testosterone-lowering activity of canola and hydrogenated soybean oil observed in SHRSP was considered in relation to other factors possibly affecting the physiology of SHRSP.


Asunto(s)
Ácidos Grasos Monoinsaturados/efectos adversos , Hipertensión/metabolismo , Aceite de Soja/efectos adversos , Accidente Cerebrovascular/metabolismo , Testosterona/metabolismo , Glándulas Suprarrenales/efectos de los fármacos , Glándulas Suprarrenales/metabolismo , Animales , Femenino , Expresión Génica/efectos de los fármacos , Hormonas Esteroides Gonadales/sangre , Hormonas Esteroides Gonadales/genética , Hormonas Esteroides Gonadales/metabolismo , Hipertensión/sangre , Hipertensión/complicaciones , Masculino , Análisis de Secuencia por Matrices de Oligonucleótidos , Ovario/efectos de los fármacos , Ovario/metabolismo , Próstata/efectos de los fármacos , Próstata/metabolismo , Aceite de Brassica napus , Ratas , Ratas Endogámicas SHR , Accidente Cerebrovascular/sangre , Accidente Cerebrovascular/complicaciones , Testículo/efectos de los fármacos , Testículo/metabolismo , Testosterona/sangre , Testosterona/genética
18.
Life Sci ; 87(15-16): 490-4, 2010 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-20837030

RESUMEN

AIMS: The purpose of this study was to determine a relatively short-term effect of feeding an α-linolenic acid (ALA, n-3)-restricted, linoleic acid (LA, n-6)-adequate diet on neurotrophin contents and protein kinase activities in brain regions of the mouse. MAIN METHODS: After feeding mice a safflower oil (SAF) diet (ALA-restricted, LA-adequate) or perilla oil (PER) diet (containing adequate amounts of ALA and LA) for 4 weeks from weaning, the fatty acid compositions of brain regions were analyzed by capillary column gas-liquid chromatography, nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) contents were measured using enzyme-linked immunosorbent assay. KEY FINDINGS: The striatum and hippocampus, but not the cerebral cortex, from the SAF group, contained a smaller amount of docosahexaenoic acid (DHA, 22:6n-3) than those from the PER group. The NGF contents in these brain regions were not different between the two dietary groups. However, the striatal BDNF content of the SAF group was significantly lower than that of the PER group. Protein kinase A, protein kinase C, and p44/42 mitogen-activated protein kinase (p44/42 MAPK) activities in brain regions showed no significant difference between the two dietary groups. However, the striatal p38 MAPK activity was significantly lower in the SAF group than in the PER group. No such differences were observed in the hippocampus or the cerebral cortex. SIGNIFICANCE: A relatively short-term feeding of an α-linolenic acid-restricted, linoleic acid-adequate diet was found to lower the DHA content, BDNF content and p38 MAPK activity in the mouse striatum.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/metabolismo , Ácidos Docosahexaenoicos/metabolismo , Proteínas Quinasas/metabolismo , Ácido alfa-Linolénico/administración & dosificación , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Animales , Corteza Cerebral/metabolismo , Cromatografía de Gases , Cromatografía Liquida , Cuerpo Estriado/metabolismo , Dieta con Restricción de Grasas , Ensayo de Inmunoadsorción Enzimática , Hipocampo/metabolismo , Masculino , Ratones , Ratones Endogámicos ICR , Factor de Crecimiento Nervioso/metabolismo
19.
Lipids ; 42(9): 821-5, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17546469

RESUMEN

Healthy ageing is gaining attention in the lipid nutrition field. As in vivo biomarkers of healthy ageing, we have evaluated the survival, learning/memory performance, and physical potencies in rodents fed a diet supplemented with high-linoleic acid (LNA, omega6) safflower oil or high-alpha-linolenic acid (ALA, omega3) perilla oil for long periods. The results suggested that perilla oil with a low omega6/omega3 ratio is beneficial for healthy ageing. In order to address this issue further, we determined the survival of stroke-prone SHR (SHRSP) rats fed a conventional rodent diet supplemented with 10% fat or oil. Survival was longer with omega3-rich oils compared with omega6-rich oils. However, some kinds of vegetable oils and hydrogenated oils shortened the survival of SHRSP rats to an unusual degree (ca. 40% compared with that of omega6-rich oil) that could not be accounted for by the fatty acid and phytosterol composition of the oils. The observed decrease in platelet counts was associated with pathological changes in the kidney and other organs. Dihydro-vitamin K1 is proposed as a likely candidate as a stroke-stimulating factor in hydrogenated oils. Thus, factors other than fatty acids (omega6/omega3 balance) and phytosterols must be taken into account when fats and oils are evaluated in relation to healthy ageing.


Asunto(s)
Envejecimiento/efectos de los fármacos , Grasas Insaturadas en la Dieta/farmacología , Animales , Humanos , Aceites de Plantas/farmacología , Ratas , Ratas Endogámicas SHR , Aceite de Cártamo/farmacología , Accidente Cerebrovascular/enzimología , Accidente Cerebrovascular/metabolismo , Ácido alfa-Linolénico/farmacología
20.
Nihon Koshu Eisei Zasshi ; 52(10): 865-73, 2005 Oct.
Artículo en Japonés | MEDLINE | ID: mdl-16334407

RESUMEN

OBJECTIVES: The study was conducted to analyze risk, causes and places of death, and related factors among elderly with and without dementia in a community. METHODS: In 1994, the entire elderly population, aged 65 and older in city K were surveyed for their health status. Among them, 201 were diagnosed as suffering from dementia by psychiatric doctors, according to DSM-III-R. Date, causes and places of death were surveyed individually using the vital statistics record of the national government, for ten years from July 1, 1994. The risk of death adjusted for age-classes, was analyzed with the Cox proportional hazard model. Median survival time was calculated using the Kaplan-Maier method, and causes and places of death were analyzed with the chi2 test. Ten factors at the baseline study were examined for each sex, to analyze their relations to death. RESULTS: Among 198 elderly with dementia followed, 170 died (85.9%), while 1696 (33.9%) died in the 5004 non-dementia group. The hazard ratio for dementia/non-dementia was 2.99, and the female/male was 0.56, stratified by age-classes. The rate for death due to CVD in the elderly with dementia was particularly high accounting for 37.1% of the total. With the CVD and undifferentiated types of dementia, the rate was 47.0%. The rate for malignant tumor was low. In the dementia group, mortality at nursing homes was higher and at hospitals/clinics was lower, compared to non-dementia group (p< 0.05). When stratified by age-classes, the factors significantly related to death of the elderly with dementia were severity of dementia (male), type of dementia (female), being bed-ridden and having impaired walking or toileting capabilities (both sexes). CONCLUSIONS: Dementia is a significant death related factor for elderly people, particularly linked to mortality from cerebro-vascular disease. The type and severity of dementia, and walking or toileting activities appear significant to be factors for death of elderly with dementia.


Asunto(s)
Causas de Muerte , Demencia/mortalidad , Anciano , Anciano de 80 o más Años , Trastornos Cerebrovasculares/mortalidad , Comorbilidad , Femenino , Estudios de Seguimiento , Estado de Salud , Humanos , Japón/epidemiología , Masculino , Neoplasias/mortalidad , Modelos de Riesgos Proporcionales
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