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1.
Zoolog Sci ; 41(1): 60-67, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38587518

RESUMEN

Ovarian follicle development is an essential process for continuation of sexually reproductive animals, and is controlled by a wide variety of regulatory factors such as neuropeptides and peptide hormones in the endocrine, neuroendocrine, and nervous systems. Moreover, while some molecular mechanisms underlying follicle development are conserved, others vary among species. Consequently, follicle development processes are closely related to the evolution and diversity of species. Ciona intestinalis type A (Ciona rubusta) is a cosmopolitan species of ascidians, which are the closest relative of vertebrates. However, unlike vertebrates, ascidians are not endowed with the hypothalamus-pituitary-gonadal axis involving pituitary gonadotropins and sexual steroids. Combined with the phylogenetic position of ascidians as the closest relative of vertebrates, such morphological and endocrine features suggest that ascidians possess both common and species-specific regulatory mechanisms in follicle development. To date, several neuropeptides have been shown to participate in the growth of vitellogenic follicles, oocyte maturation of postvitellogenic follicles, and ovulation of fully mature follicles in a developmental stage-specific fashion. Furthermore, recent studies have shed light on the evolutionary processes of follicle development throughout chordates. In this review, we provide an overview of the neuropeptidergic molecular mechanism in the premature follicle growth, oocyte maturation, and ovulation in Ciona, and comparative views of the follicle development processes of mammals and teleosts.


Asunto(s)
Ciona intestinalis , Neuropéptidos , Animales , Femenino , Filogenia , Ovulación , Folículo Ovárico , Mamíferos
2.
Int J Mol Sci ; 21(22)2020 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-33198405

RESUMEN

Gonadotropin-releasing hormones (GnRHs) play pivotal roles in reproduction via the hypothalamus-pituitary-gonad axis (HPG axis) in vertebrates. GnRHs and their receptors (GnRHRs) are also conserved in invertebrates lacking the HPG axis, indicating that invertebrate GnRHs do not serve as "gonadotropin-releasing factors" but, rather, function as neuropeptides that directly regulate target tissues. All vertebrate and urochordate GnRHs comprise 10 amino acids, whereas amphioxus, echinoderm, and protostome GnRH-like peptides are 11- or 12-residue peptides. Intracellular calcium mobilization is the major second messenger for GnRH signaling in cephalochordates, echinoderms, and protostomes, while urochordate GnRHRs also stimulate cAMP production pathways. Moreover, the ligand-specific modulation of signal transduction via heterodimerization between GnRHR paralogs indicates species-specific evolution in Ciona intestinalis. The characterization of authentic or putative invertebrate GnRHRs in various tissues and their in vitro and in vivo activities indicate that invertebrate GnRHs are responsible for the regulation of both reproductive and nonreproductive functions. In this review, we examine our current understanding of and perspectives on the primary sequences, tissue distribution of mRNA expression, signal transduction, and biological functions of invertebrate GnRHs and their receptors.


Asunto(s)
Hipotálamo/metabolismo , Invertebrados/metabolismo , Receptores LHRH/metabolismo , Animales , Evolución Biológica , Células COS , Calcio/metabolismo , Chlorocebus aethiops , Ciona intestinalis , AMP Cíclico/metabolismo , Equinodermos , Femenino , Hormona Liberadora de Gonadotropina/metabolismo , Células HEK293 , Humanos , Ligandos , Masculino , Cadenas de Markov , Moluscos , Transducción de Señal , Distribución Tisular , Urocordados
3.
Cell Tissue Res ; 377(3): 293-308, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31079207

RESUMEN

The digestive system is responsible for nutrient intake and defense against pathogenic microbes. Thus, identification of regulatory factors for digestive functions and immune systems is a key step to the verification of the life cycle, homeostasis, survival strategy and evolutionary aspects of an organism. Over the past decade, there have been increasing reports on neuropeptides, their receptors, variable region-containing chitin-binding proteins (VCBPs) and Toll-like receptors (TLRs) in the ascidian, Ciona intestinalis. Mass spectrometry-based peptidomes and genome database-searching detected not only Ciona orthologs or prototypes of vertebrate peptides and their receptors, including cholecystokinin, gonadotropin-releasing hormones, tachykinin, calcitonin and vasopressin but also Ciona-specific neuropeptides including Ci-LFs and Ci-YFVs. The species-specific regulation of GnRHergic signaling including unique signaling control via heterodimerization among multiple GnRH receptors has also been revealed. These findings shed light on the remarkable significance of ascidians in investigations of the evolution and diversification of the peptidergic systems in chordates. In the defensive systems of C. intestinalis, VCBPs and TLRs have been shown to play major roles in the recognition of exogenous microbes in the innate immune system. These findings indicate both common and species-specific functions of the innate immunity-related molecules between C. intestinalis and vertebrates. In this review article, we present recent advances in molecular and functional features and evolutionary aspects of major neuropeptides, their receptors, VCBPs and TLRs in C. intestinalis.


Asunto(s)
Ciona intestinalis , Sistema Digestivo , Neuropéptidos , Receptores de Péptidos , Receptores Toll-Like , Animales , Ciona intestinalis/inmunología , Ciona intestinalis/metabolismo , Sistema Digestivo/inmunología , Sistema Digestivo/metabolismo , Neuropéptidos/química , Neuropéptidos/genética , Filogenia , Receptores de Péptidos/química , Receptores de Péptidos/genética , Especificidad de la Especie , Receptores Toll-Like/química , Receptores Toll-Like/genética
4.
Inorg Chem ; 57(11): 6648-6657, 2018 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-29790349

RESUMEN

We have investigated high-pressure, high-temperature phase transitions of spinel (Sp)-type MgV2O4, FeV2O4, and MnCr2O4. At 1200-1800 °C, MgV2O4 Sp decomposes at 4-7 GPa into a phase assemblage of MgO periclase + corundum (Cor)-type V2O3, and they react at 10-15 GPa to form a phase with a calcium titanite (CT)-type structure. FeV2O4 Sp transforms to CT-type FeV2O4 at 12 GPa via decomposition phases of FeO wüstite + Cor-type V2O3. MnCr2O4 Sp directly transforms to the calcium ferrite (CF)-structured phase at 10 GPa and 1000-1400 °C. Rietveld refinements of CT-type MgV2O4 and FeV2O4 and CF-type MnCr2O4 confirm that both the CT- and CF-type structures have frameworks formed by double chains of edge-shared B3+O6 octahedra (B3+ = V3+ and Cr3+) running parallel to one of orthorhombic cell axes. A relatively large A2+ cation (A2+ = Mg2+, Fe2+, and Mn2+) occupies a tunnel-shaped space formed by corner-sharing of four double chains. Effective coordination numbers calculated from eight neighboring oxygen-A2+ cation distances of CT-type MgV2O4 and FeV2O4 and CF-type MnCr2O4 are 5.50, 5.16, and 7.52, respectively. This implies that the CT- and CF-type structures practically have trigonal prism (six-coordinated) and bicapped trigonal prism (eight-coordinated) sites for the A2+ cations, respectively. A relationship between cation sizes of VIIIA2+ and VIB3+ and crystal structures (CF- and CT-types) of A2+B23+O4 is discussed using the above new data and available previous data of the postspinel phases. We found that CF-type A2+B23+O4 crystallize in wide ionic radius ranges of 0.9-1.4 Å for VIIIA2+ and 0.55-1.1 Å for VIB3+, whereas CT-type phases crystallize in very narrow ionic radius ranges of ∼0.9 Å for VIIIA2+ and 0.6-0.65 Å for VIB3+. This would be attributed to the fact that the tunnel space of CT-type structure is geometrically less flexible due to the smaller coordination number for A2+ cation than that of CF-type.

5.
Chembiochem ; 17(24): 2324-2333, 2016 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-27685371

RESUMEN

The transfer of photoenergized electrons from extracellular photosensitizers across a bacterial cell envelope to drive intracellular chemical transformations represents an attractive way to harness nature's catalytic machinery for solar-assisted chemical synthesis. In Shewanella oneidensis MR-1 (MR-1), trans-outer-membrane electron transfer is performed by the extracellular cytochromes MtrC and OmcA acting together with the outer-membrane-spanning porin⋅cytochrome complex (MtrAB). Here we demonstrate photoreduction of solutions of MtrC, OmcA, and the MtrCAB complex by soluble photosensitizers: namely, eosin Y, fluorescein, proflavine, flavin, and adenine dinucleotide, as well as by riboflavin and flavin mononucleotide, two compounds secreted by MR-1. We show photoreduction of MtrC and OmcA adsorbed on RuII -dye-sensitized TiO2 nanoparticles and that these protein-coated particles perform photocatalytic reduction of solutions of MtrC, OmcA, and MtrCAB. These findings provide a framework for informed development of strategies for using the outer-membrane-associated cytochromes of MR-1 for solar-driven microbial synthesis in natural and engineered bacteria.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/metabolismo , Colorantes/química , Grupo Citocromo c/metabolismo , Titanio/química , Catálisis , Transporte de Electrón , Eosina Amarillenta-(YS)/química , Compuestos Férricos/química , Mononucleótido de Flavina/química , Luz , Nanopartículas del Metal/química , Oxidación-Reducción , Fármacos Fotosensibilizantes/química , Shewanella
6.
Gen Comp Endocrinol ; 227: 101-8, 2016 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-26031189

RESUMEN

Ascidians are the closest phylogenetic neighbors to vertebrates and are believed to conserve the evolutionary origin in chordates of the endocrine, neuroendocrine, and nervous systems involving neuropeptides and peptide hormones. Ciona intestinalis harbors various homologs or prototypes of vertebrate neuropeptides and peptide hormones including gonadotropin-releasing hormones (GnRHs), tachykinins (TKs), and calcitonin, as well as Ciona-specific neuropeptides such as Ciona vasopressin, LF, and YFV/L peptides. Moreover, molecular and functional studies on Ciona tachykinin (Ci-TK) have revealed the novel molecular mechanism of inducing oocyte growth via up-regulation of vitellogenesis-associated protease activity, which is expected to be conserved in vertebrates. Furthermore, a series of studies on Ciona GnRH receptor paralogs have verified the species-specific regulation of GnRHergic signaling including unique signaling control via heterodimerization among multiple GnRH receptors. These findings confirm the remarkable significance of ascidians in investigations of the evolutionary processes of the peptidergic systems in chordates, leading to the promising advance in the research on Ciona peptides in the next stage based on the recent development of emerging technologies including genome-editing techniques, peptidomics-based multi-color staining, machine-learning prediction, and next-generation sequencing. These technologies and bioinformatic integration of the resultant "multi-omics" data will provide unprecedented insights into the comprehensive understanding of molecular and functional regulatory mechanisms of the Ciona peptides, and will eventually enable the exploration of both conserved and diversified endocrine, neuroendocrine, and nervous systems in the evolutionary lineage of chordates.


Asunto(s)
Evolución Biológica , Ciona intestinalis/metabolismo , Neuropéptidos/metabolismo , Transducción de Señal/fisiología , Animales , Oogénesis/fisiología , Filogenia , Regulación hacia Arriba , Vertebrados/metabolismo
7.
JAMA Netw Open ; 7(7): e2423544, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-39078632

RESUMEN

Importance: There is currently no consensus on clinically effective interventions for polypharmacy among older inpatients. Objective: To evaluate the effect of multidisciplinary team-based medication optimization on survival, unscheduled hospital visits, and rehospitalization in older inpatients with polypharmacy. Design, Setting, and Participants: This open-label randomized clinical trial was conducted at 8 internal medicine inpatient wards within a community hospital in Japan. Participants included medical inpatients 65 years or older who were receiving 5 or more regular medications. Enrollment took place between May 21, 2019, and March 14, 2022. Statistical analysis was performed from September 2023 to May 2024. Intervention: The participants were randomly assigned to receive either an intervention for medication optimization or usual care including medication reconciliation. The intervention consisted of a medication review using the STOPP (Screening Tool of Older Persons' Prescriptions)/START (Screening Tool to Alert to Right Treatment) criteria, followed by a medication optimization proposal for participants and their attending physicians developed by a multidisciplinary team. On discharge, the medication optimization summary was sent to patients' primary care physicians and community pharmacists. Main Outcomes and Measures: The primary outcome was a composite of death, unscheduled hospital visits, and rehospitalization within 12 months. Secondary outcomes included the number of prescribed medications, falls, and adverse events. Results: Between May 21, 2019, and March 14, 2022, 442 participants (mean [SD] age, 81.8 [7.1] years; 223 [50.5%] women) were randomly assigned to the intervention (n = 215) and usual care (n = 227). The intervention group had a significantly lower percentage of patients with 1 or more potentially inappropriate medications than the usual care group at discharge (26.2% vs 33.0%; adjusted odds ratio [OR], 0.56 [95% CI, 0.33-0.94]; P = .03), at 6 months (27.7% vs 37.5%; adjusted OR, 0.50 [95% CI, 0.29-0.86]; P = .01), and at 12 months (26.7% vs 37.4%; adjusted OR, 0.45 [95% CI, 0.25-0.80]; P = .007). The primary composite outcome occurred in 106 participants (49.3%) in the intervention group and 117 (51.5%) in the usual care group (stratified hazard ratio, 0.98 [95% CI, 0.75-1.27]). Adverse events were similar between each group (123 [57.2%] in the intervention group and 135 [59.5%] in the usual care group). Conclusions and Relevance: In this randomized clinical trial of older inpatients with polypharmacy, the multidisciplinary deprescribing intervention did not reduce death, unscheduled hospital visits, or rehospitalization within 12 months. The intervention was effective in reducing the number of medications with no significant adverse effects on clinical outcomes, even among older inpatients with polypharmacy. Trial Registration: UMIN Clinical Trials Registry: UMIN000035265.


Asunto(s)
Polifarmacia , Humanos , Femenino , Masculino , Anciano , Anciano de 80 o más Años , Japón , Pacientes Internos/estadística & datos numéricos , Conciliación de Medicamentos/métodos , Readmisión del Paciente/estadística & datos numéricos , Grupo de Atención al Paciente
8.
Angew Chem Int Ed Engl ; 52(47): 12313-6, 2013 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-24115736

RESUMEN

Take a breath: An oxygen-tolerant hydrogenase can be employed with a dye in a photocatalytic scheme for the generation of H2 . The homogeneous system does not require a redox mediator and visible-light irradiation yields high amounts of H2 even in the presence of air.

9.
Eur J Case Rep Intern Med ; 10(1): 003735, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36819651

RESUMEN

A 32-year-old woman presented to the outpatient clinic with persistent fever, anterior neck pain, and palpitations over the past week which developed 2 days after she had received the first dose of the Pfizer/BioNTech SARS-CoV-2 mRNA vaccine. On examination, the patient's heart rate was 140 beats per minute and the thyroid gland was tender on palpation. Laboratory studies showed a low serum TSH level with elevated free thyroxine. Thyroid ultrasound revealed low-echoic lesions compatible with the site of tenderness. The patient was diagnosed with subacute thyroiditis and treatment was initiated with acetaminophen and propranolol, which resulted in symptom resolution within 2 weeks. Clinicians should be aware that subacute thyroiditis may occur within a few days following COVID-19 vaccination, especially in patients with anterior cervical pain with no significant abnormal pharyngeal findings and/or severe palpitations, because differentiating them from early non-specific adverse reactions can be challenging. LEARNING POINTS: Cases of subacute thyroiditis after vaccination, including against COVID-19, have been increasingly reported.Subacute thyroiditis should be considered in patients with anterior cervical pain with no significant abnormal pharyngeal findings and/or severe palpitations after COVID-19 vaccination because these can be diagnostic clues.It is important to note that this condition can occur as early as a few days after vaccination, in order to avoid diagnostic pitfalls.

10.
Front Endocrinol (Lausanne) ; 14: 1260600, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37842312

RESUMEN

Invertebrates lack hypothalamic-pituitary-gonadal axis, and have acquired species-specific regulatory systems for ovarian follicle development. Ascidians are marine invertebrates that are the phylogenetically closest living relatives to vertebrates, and we have thus far substantiated the molecular mechanisms underlying neuropeptidergic follicle development of the cosmopolitan species, Ciona intestinalis Type A. However, no ovarian factor has so far been identified in Ciona. In the present study, we identified a novel Ciona-specific peptide, termed PEP51, in the ovary. Immunohistochemical analysis demonstrated the specific expression of PEP51 in oocyte-associated accessory cells, test cells, of post-vitellogenic (stage III) follicles. Immunoelectron microscopy revealed that PEP51 was localized in the cytosol of test cells in early stage III follicles, which lack secretory granules. These results indicate that PEP51 acts as an intracellular factor within test cells rather than as a secretory peptide. Confocal laser microscopy verified that activation of caspase-3/7, the canonical apoptosis marker, was detected in most PEP51-positive test cells of early stage III. This colocalization of PEP51 and the apoptosis marker was consistent with immunoelectron microscopy observations demonstrating that a few normal (PEP51-negative) test cells reside in the aggregates of PEP51-positive apoptotic test cells of early stage III follicles. Furthermore, transfection of the PEP51 gene into COS-7 cells and HEK293MSR cells resulted in activation of caspase-3/7, providing evidence that PEP51 induces apoptotic signaling. Collectively, these results showed the existence of species-specific ovarian peptide-driven cell metabolism in Ciona follicle development. Consistent with the phylogenetic position of Ciona as the closest sister group of vertebrates, the present study sheds new light on the molecular and functional diversity of the regulatory systems of follicle development in the Chordata.


Asunto(s)
Ciona intestinalis , Animales , Femenino , Ciona intestinalis/genética , Filogenia , Caspasa 3/genética , Aminoácidos/metabolismo , Péptidos/metabolismo , Folículo Ovárico , Vertebrados
11.
Intern Med ; 61(3): 357-360, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34334568

RESUMEN

We herein report a case of large-vessel vasculitis in a 57-year-old woman who developed an intermittent fever and weight loss. While contrast-enhanced computed tomography was noncontributory, positron emission tomography-computed tomography (PET-CT) revealed the diffuse, intense uptake of fluorodeoxyglucose (FDG) in the aorta and its branches. Although she had no signs of relapse after successful oral corticosteroid therapy, PET-CT at 30 months revealed a persistent FDG uptake in the large vessels, which warranted regular follow-up imaging for vascular complications. In cases with an intense FDG uptake at the diagnosis, PET-CT follow-up after clinical remission may help predict the risk of relapse and vascular complications.


Asunto(s)
Arteritis , Arteritis de Células Gigantes , Aorta , Femenino , Fluorodesoxiglucosa F18 , Humanos , Persona de Mediana Edad , Tomografía Computarizada por Tomografía de Emisión de Positrones , Tomografía de Emisión de Positrones , Radiofármacos , Tomografía Computarizada por Rayos X
12.
Front Endocrinol (Lausanne) ; 13: 858885, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35321341

RESUMEN

Omics studies contribute to the elucidation of genomes and profiles of gene expression. In the ascidian Ciona intestinalis Type A (Ciona robusta), mass spectrometry (MS)-based peptidomic studies have detected numerous Ciona-specific (nonhomologous) neuropeptides as well as Ciona homologs of typical vertebrate neuropeptides and hypothalamic peptide hormones. Candidates for cognate G protein-coupled receptors (GPCRs) for these peptides have been found in the Ciona transcriptome by two ways. First, Ciona homologous GPCRs of vertebrate counterparts have been detected by sequence homology searches of cognate transcriptomes. Second, the transcriptome-derived GPCR candidates have been used for machine learning-based systematic prediction of interactions not only between Ciona homologous peptides and GPCRs but also between novel Ciona peptides and GPCRs. These data have ultimately led to experimental evidence for various Ciona peptide-GPCR interactions. Comparative transcriptomics between the wildtype and Ciona vasopressin (CiVP) gene-edited Ciona provide clues to the biological functions of CiVP in ovarian follicular development and whole body growth. Furthermore, the transcriptomes of follicles treated with peptides, such as Ciona tachykinin and cionin (a Ciona cholecystokinin homolog), have revealed key regulatory genes for Ciona follicle growth, maturation, and ovulation, eventually leading to the verification of essential and novel molecular mechanisms underlying these biological events. These findings indicate that omics studies, combined with artificial intelligence and single-cell technologies, pave the way for investigating in greater details the nervous, neuroendocrine, and endocrine systems of ascidians and the molecular and functional evolution and diversity of peptidergic regulatory networks throughout chordates.


Asunto(s)
Ciona intestinalis , Neuropéptidos , Hormonas Peptídicas , Animales , Inteligencia Artificial , Ciona intestinalis/genética , Ciona intestinalis/metabolismo , Femenino , Neuropéptidos/metabolismo , Hormonas Peptídicas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Vertebrados/metabolismo
13.
Bone Joint J ; 104-B(1): 97-102, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34969274

RESUMEN

AIMS: To develop and internally validate a preoperative clinical prediction model for acute adjacent vertebral fracture (AVF) after vertebral augmentation to support preoperative decision-making, named the after vertebral augmentation (AVA) score. METHODS: In this prognostic study, a multicentre, retrospective single-level vertebral augmentation cohort of 377 patients from six Japanese hospitals was used to derive an AVF prediction model. Backward stepwise selection (p < 0.05) was used to select preoperative clinical and imaging predictors for acute AVF after vertebral augmentation for up to one month, from 14 predictors. We assigned a score to each selected variable based on the regression coefficient and developed the AVA scoring system. We evaluated sensitivity and specificity for each cut-off, area under the curve (AUC), and calibration as diagnostic performance. Internal validation was conducted using bootstrapping to correct the optimism. RESULTS: Of the 377 patients used for model derivation, 58 (15%) had an acute AVF postoperatively. The following preoperative measures on multivariable analysis were summarized in the five-point AVA score: intravertebral instability (≥ 5 mm), focal kyphosis (≥ 10°), duration of symptoms (≥ 30 days), intravertebral cleft, and previous history of vertebral fracture. Internal validation showed a mean optimism of 0.019 with a corrected AUC of 0.77. A cut-off of ≤ one point was chosen to classify a low risk of AVF, for which only four of 137 patients (3%) had AVF with 92.5% sensitivity and 45.6% specificity. A cut-off of ≥ four points was chosen to classify a high risk of AVF, for which 22 of 38 (58%) had AVF with 41.5% sensitivity and 94.5% specificity. CONCLUSION: In this study, the AVA score was found to be a simple preoperative method for the identification of patients at low and high risk of postoperative acute AVF. This model could be applied to individual patients and could aid in the decision-making before vertebral augmentation. Cite this article: Bone Joint J 2022;104-B(1):97-102.


Asunto(s)
Técnicas de Apoyo para la Decisión , Fracturas por Compresión/etiología , Complicaciones Posoperatorias/etiología , Fracturas de la Columna Vertebral/etiología , Vertebroplastia , Anciano , Anciano de 80 o más Años , Femenino , Fracturas por Compresión/diagnóstico por imagen , Humanos , Japón , Masculino , Complicaciones Posoperatorias/diagnóstico por imagen , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Sensibilidad y Especificidad , Fracturas de la Columna Vertebral/diagnóstico por imagen
14.
Mol Biol Evol ; 27(5): 1097-106, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20026483

RESUMEN

Gonadotropin-releasing hormones (GnRHs) play pivotal roles in control of reproduction via a hypothalamic-pituitary-periphery endocrine system and nervous systems of not only vertebrates but also invertebrates. GnRHs trigger several signal transduction cascades via GnRH receptors (GnRHRs), members of the G protein-coupled receptor (GPCR) family. Recently, six GnRHs (tunicate GnRH [tGnRH]-3 to tGnRH-8) and four GnRHRs (Ciona intestinalis [Ci]-GnRHR1 to GnRHR-4), including a species-specific paralog, Ci-GnRHR4 (R4) regarded as an orphan receptor or nonfunctional receptor, were identified in the protochordate, C. intestinalis, which lacks the hypothalamic-pituitary system. Here, we show novel functional modulation of GnRH signaling pathways via GPCR heterodimerization. Immunohistochemical analysis showed colocalization of R1 and R4 in test cells of the ascidian ovary. The native R1-R4 heterodimerization was detected in the Ciona ovary by coimmunoprecipitation analysis. The heterodimerization in HEK293 cells cotransfected with R1 and R4 was also observed by coimmunoprecipitation and fluorescent energy transfer analyses. Binding assay revealed that R4 had no affinity for tGnRHs, and the heterodimerization did not alter the binding affinity of R1 to the ligands. The R1-R4 elicited 10-fold more potent Ca2+ mobilization than R1 exclusively by tGnRH-6, although R1-mediated cyclic AMP production was not affected by any of tGnRHs via the R1-R4 heterodimer. Moreover, the R1-R4 heterodimer potentiated translocation of both Ca2+-dependent protein kinase C-alpha (PKCalpha) by tGnRH-6 and Ca2+-independent PKCzeta by tGnRH-5 and tGnRH-6, eventually leading to the upregulation of extracellular signal-regulated kinase (ERK) phosphorylation compared with R1 alone. These results provide evidence that the species-specific GnRHR orphan paralog, R4, serves as an endogenous modulator for the fine-tuning of activation of PKC subtype-selective signal transduction via heterodimerization with R1 and that the species-specific GPCR heterodimerization, in concert with multiplication of tGnRHs and Ci-GnRHRs, participates in functional evolution of neuropeptidergic GnRH signaling pathways highly conserved throughout the animal kingdom.


Asunto(s)
Ciona intestinalis/metabolismo , Receptores Nucleares Huérfanos/metabolismo , Multimerización de Proteína , Receptores LHRH/metabolismo , Transducción de Señal , Animales , Línea Celular , Membrana Celular/efectos de los fármacos , Membrana Celular/enzimología , Ciona intestinalis/citología , Ciona intestinalis/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Femenino , Transferencia Resonante de Energía de Fluorescencia , Hormona Liberadora de Gonadotropina/farmacología , Humanos , Concentración 50 Inhibidora , Espacio Intracelular/efectos de los fármacos , Espacio Intracelular/metabolismo , Ligandos , Modelos Biológicos , Ovario/citología , Ovario/efectos de los fármacos , Ovario/metabolismo , Fosforilación/efectos de los fármacos , Unión Proteica/efectos de los fármacos , Proteína Quinasa C/metabolismo , Multimerización de Proteína/efectos de los fármacos , Transporte de Proteínas/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Especificidad de la Especie
15.
Zoolog Sci ; 27(2): 134-53, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20141419

RESUMEN

The critical phylogenetic position of ascidians leads to the presumption that neuropeptides and hormones in vertebrates are highly likely to be evolutionarily conserved in ascidians, and the cosmopolitan species Ciona intestinalis is expected to be an excellent deuterostome Invertebrate model for studies on neuropeptides and hormones. Nevertheless, molecular and functional characterization of Ciona neuropeptides and hormone peptides was restricted to a few peptides such as a cholecystokinin (CCK)/gastrin peptide, cionin, and gonadotropin-releasing hormones (GnRHs). In the past few years, mass spectrometric analyses and database searches have detected Ciona orthologs or prototypes of vertebrate peptides and their receptors, including tachykinin, insulin/relaxin, calcitonin, and vasopressin. Furthermore, studies have shown that several Ciona peptides, including vasopressin and a novel GnRH-related peptide, have acquired ascidian-specific molecular forms and/or biological functions. These findings provided indisputable evidence that ascidians, unlike other invertebrates (including the traditional protostome model animals), possess neuropeptides and hormone peptides structurally and functionally related to vertebrate counterparts, and that several peptides have uniquely diverged in ascidian evolutionary lineages. Moreover, recent functional analyses of Ciona tachykinin in the ovary substantiated the novel tachykininergic protease-assoclated oocyte growth pathway, which could not have been revealed in studies on vertebrates. These findings confirm the outstanding advantages of ascidians in understanding the neuroscience, endocrinology, and evolution of vertebrate neuropeptides and hormone peptides. This article provides an overview of basic findings and reviews new knowledge on ascidian neuropeptides and hormone peptides.


Asunto(s)
Ciona intestinalis/metabolismo , Neuropéptidos/metabolismo , Receptores de Neuropéptido/metabolismo , Receptores de Péptidos/metabolismo , Animales , Evolución Molecular , Regulación de la Expresión Génica/fisiología
16.
BMJ Open ; 10(10): e041125, 2020 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-33046478

RESUMEN

INTRODUCTION: Whether medication optimisation improves clinical outcomes in elderly individuals remains unclear. The current study aims to evaluate the effect of multidisciplinary team-based medication optimisation on survival, rehospitalisation and unscheduled hospital visits in elderly patients. METHODS AND ANALYSIS: We report the protocol of a single-centre, open-label, randomised controlled trial. The enrolled subjects will be medical inpatients, aged 65 years or older, admitted to a community hospital and receiving five or more regular medications. The participants will be randomly assigned to receive either an intervention for medication optimisation or the usual care. The intervention will consist of a multidisciplinary team-based medication review, followed by a medication optimisation proposal based on the Screening Tool of Older Persons' potentially inappropriate Prescriptions/Screening Tool to Alert doctors to the Right Treatment criteria and an implicit medication optimisation protocol. Medication optimisation summaries will be sent to primary care physicians and community pharmacists on discharge. The primary outcome will be a composite of death, unscheduled hospital visits and rehospitalisation until 48 weeks after randomisation. Secondary outcomes will include each of the primary endpoints, the number of prescribed medications, quality of life score, level of long-term care required, drug-related adverse events, death during hospitalisation and falls. Participants will be followed up for 48 weeks with bimonthly telephone interviews to assess the primary and secondary outcomes. A log-rank test stratified by randomisation factors will be used to compare the incidence of the composite endpoint. The study was initiated in 2019 and a minimum of 500 patients will be enrolled. ETHICS AND DISSEMINATION: The study protocol has been approved by the Institutional Ethical Committee of St. Marianna University School of Medicine (No. 4129). The results of the current study will be submitted to a peer-reviewed journal. TRIAL REGISTRATION NUMBER: UMIN000035265.


Asunto(s)
Geriatría , Administración del Tratamiento Farmacológico , Anciano , Anciano de 80 o más Años , Hospitalización , Humanos , Prescripción Inadecuada , Pacientes Internos , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto
17.
Physiol Behav ; 96(4-5): 548-56, 2009 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-19146864

RESUMEN

It has been shown that in orthopteran insects each of the optic lobes (OLs) contains a circadian pacemaker controlling locomotor activity and that the pars intercerebralis (PI) modifies the activity level. However, the present study showed Period protein-like immunoreactivity (PER-ir) in the PI and dorsolateral protocerebrum (DL) as well as in the OLs in the American cockroach, Periplaneta americana, which raised the possibility that the PI or DL could be a clock element. Therefore, we removed the PI or DL surgically and observed the effects on locomotor rhythms and feeding behavior. In constant darkness (DD), cockroaches with an ablated PI (PIX-DD) showed arrhythmicity in locomotion and a massive increase in food consumption that led to increased body length and weight, while PIX cockroaches reared under LD 12:12 (PIX-LD) and the sham-treated cockroaches in DD (CNT-DD) showed rhythmicity and no increase in food consumption. Statistical analysis showed that arrhythmicity was not accompanied by hyperactivity, suggesting that the PI is involved in the regulation of locomotor activity and feeding in DD. The activities of alpha-amylase and proteases were found to be markedly elevated in the midgut of PIX-DD cockroaches but not in PIX-LD cockroaches. Taken together, these results indicate that the PI modulates locomotor rhythms and feeding behavior of cockroaches in a light-dependent manner. The PI and the OL may regulate circadian rhythms and feeding via distinct pathways.


Asunto(s)
Ritmo Circadiano/fisiología , Conducta Alimentaria/fisiología , Ganglios de Invertebrados/fisiología , Actividad Motora/fisiología , Lóbulo Óptico de Animales no Mamíferos/fisiología , Periplaneta/fisiología , Análisis de Varianza , Animales , Encéfalo/anatomía & histología , Encéfalo/fisiología , Conducta Alimentaria/efectos de la radiación , Inmunohistoquímica , Luz , Masculino , Actividad Motora/efectos de la radiación , Proteínas Nucleares/metabolismo , Proteínas Circadianas Period , Periplaneta/anatomía & histología , Fotoperiodo , Distribución Tisular
18.
Results Probl Cell Differ ; 68: 107-125, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31598854

RESUMEN

The critical phylogenetic position of the ascidian, Ciona intestinalis, as the closest relative of vertebrates, suggested its potential applicability as a model organism in a wide variety of biological events including the nervous, neuroendocrine, and endocrine regulation. To date, approximately 40 neuropeptides and/or peptide hormones and several cognate receptors have been identified. These peptides are categorized into two types: (1) orthologs of vertebrate peptides, such as cholecystokinin, GnRH, tachykinin, vasopressin, and calcitonin, and (2) novel family peptides such as LF peptides and YFL/V peptides. Ciona GnRH receptors (Ci-GnRHR) were found to be multiplicated in the Ciona-specific lineages and to form unique heterodimers between Ci-GnRHR1 and R4 and between Ci-GnRHR2 and R4, leading to fine-tuning of the generation of second messengers. Furthermore, Ciona tachykinin was shown to regulate a novel protease-associated follicle growth pathway. These findings will pave the way for the exploration of both conserved and diversified endocrine, neuroendocrine, and nervous systems in the evolutionary lineage of invertebrate deuterostomes and/or chordates. In this chapter, we provide an overview of primary sequences, functions, and evolutionary aspects of neuropeptides, peptide hormones, and their receptors in C. intestinalis.


Asunto(s)
Ciona intestinalis/metabolismo , Neuropéptidos/metabolismo , Hormonas Peptídicas/metabolismo , Receptores de Péptidos/metabolismo , Animales , Filogenia
19.
Endocrinology ; 149(9): 4346-56, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18483149

RESUMEN

Tachykinins (TKs) and their receptors have been shown to be expressed in the mammalian ovary. However, the biological roles of ovarian TKs have yet to be verified. Ci-TK-I and Ci-TK-R, characterized from the protochordate (ascidian), Ciona intestinalis, are prototypes of vertebrate TKs and their receptors. In the present study, we show a novel biological function of TKs as an inducible factor for oocyte growth using C. intestinalis as a model organism. Immunostaining demonstrated the specific expression of Ci-TK-R in test cells residing in oocytes at the vitellogenic stage. DNA microarray and real-time PCR revealed that Ci-TK-I induced gene expression of several proteases, including cathepsin D, chymotrypsin, and carboxy-peptidase B1, in the ovary. The enzymatic activities of these proteases in the ovary were also shown to be enhanced by Ci-TK-I. Of particular significance is that the treatment of Ciona oocytes with Ci-TK-I resulted in progression of growth from the vitellogenic stage to the post-vitellogenic stage. The Ci-TK-I-induced oocyte growth was blocked by a TK antagonist or by protease inhibitors. These results led to the conclusion that Ci-TK-I enhances growth of the vitellogenic oocytes via up-regulation of gene expression and enzymatic activities of the proteases. This is the first clarification of the biological roles of TKs in the ovary and the underlying essential molecular mechanism. Furthermore, considering the phylogenetic position of ascidians as basal chordates, we suggest that the novel TK-regulated oocyte growth is an "evolutionary origin" of the tachykininergic functions in the ovary.


Asunto(s)
Evolución Biológica , Ciona intestinalis/fisiología , Oocitos/efectos de los fármacos , Ovario/efectos de los fármacos , Taquicininas/farmacología , Animales , Femenino , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Modelos Biológicos , Oocitos/crecimiento & desarrollo , Oogénesis/efectos de los fármacos , Ovario/metabolismo , Ovario/fisiología , Péptido Hidrolasas/genética , Péptido Hidrolasas/metabolismo , Receptores de Taquicininas/genética , Receptores de Taquicininas/metabolismo , Receptores de Taquicininas/fisiología , Distribución Tisular , Regulación hacia Arriba
20.
Protein Pept Lett ; 15(3): 300-8, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18336362

RESUMEN

G protein coupled-receptors (GPCR) have been shown to form heterodimers or heterooligomers with various biochemical and/or pharmacological activity that are distinct from those of the corresponding monomers or homomers. Recent in vitro and in vivo experimental data have also shown novel functional roles of several orphan GPCRs as modulatory units of heterodimers and potentials for development of heterodimer-selective clinical agents. In this review, we summarize essential and latest knowledge as to GPCR heterodimerizations and the current issues to be solved in the near future.


Asunto(s)
Receptores Acoplados a Proteínas G/química , Animales , Sitios de Unión , Dimerización , Humanos , Conformación Proteica , Receptores Acoplados a Proteínas G/metabolismo , Transducción de Señal
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