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1.
Neuropharmacology ; 251: 109919, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38548221

RESUMO

Ghrelin and its mimetics have been shown to reduce cisplatin-induced emesis in preclinical studies using ferrets and shrews. This study investigated the effectiveness of ghrelin and des-acyl ghrelin (DAG) in antagonizing cisplatin-induced emesis and physiological changes indicative of nausea in Suncus murinus. Animals implanted with radiotelemetry devices were administered ghrelin (0.2, 1.0, and 5.0 µg/day), DAG (0.2, 1.0, and 5.0 µg/day), or saline (14 µL/day) intracerebroventricularly 4 days before and 3 days after treatment with cisplatin (30 mg/kg). At the end, the anti-apoptotic potentials of ghrelin and DAG were assessed by measuring Bax expression and cytochrome C activity. Neurotransmitter changes in the brain were evaluated using liquid chromatography-mass spectrometry analysis. Ghrelin and DAG reduced cisplatin-induced emesis in the delayed (24-72 h) but not the acute phase (0-24 h) of emesis. Ghrelin also partially reversed the inhibitory effects of cisplatin on food intake without affecting gastrointestinal myoelectrical activity or causing hypothermia; however, ghrelin or DAG did not prevent these effects. Ghrelin and DAG could attenuate the cisplatin-induced upregulation of Bax and cytochrome C in the ileum. Cisplatin dysregulated neurotransmitter levels in the frontal cortex, amygdala, thalamus, hypothalamus, and brainstem, and this was partially restored by low doses of ghrelin and DAG. Our findings suggest that ghrelin and DAG exhibit protective effects against cisplatin-induced delayed emesis. The underlying antiemetic mechanism may involve GHSR and/or unspecified pathways that modulate the neurotransmitters involved in emesis control in the brain and an action to attenuate apoptosis in the gastrointestinal tract.


Assuntos
Antieméticos , Antineoplásicos , Animais , Cisplatino/toxicidade , Grelina/farmacologia , Grelina/uso terapêutico , Vômito/induzido quimicamente , Vômito/tratamento farmacológico , Vômito/prevenção & controle , Citocromos c , Proteína X Associada a bcl-2 , Furões , Náusea/induzido quimicamente , Náusea/tratamento farmacológico , Náusea/prevenção & controle , Antieméticos/farmacologia , Antieméticos/uso terapêutico , Antineoplásicos/toxicidade , Neurotransmissores/efeitos adversos
2.
Biochem Biophys Res Commun ; 704: 149708, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38417346

RESUMO

Glucagon like peptide-1 (GLP-1) is a peptide hormone encoded by the pre-proglucagon gene that serves multiple physiological functions, including incretin action. While GLP-1 is primarily synthesized in the L cells of the lower intestine, recent findings indicate its presence in the stomachs of both rats and humans. However, the role of gastric GLP-1 in other species remains unclear. In this study, we aimed to identify GLP-1-producing cells and examine the localization of GLP-1 production in the mouse stomach. We found that pre-proglucagon mRNA was higher in the corpus than that in the antrum of the stomach. In addition, GLP-1 immunoreactive cells were found in the gastric mucosa, and their cell number was higher in the corpus than that in the antrum. Double immunofluorescence showed that some GLP-1 immunoreactive cells displayed somatostatin immunoreactivity, whereas did not co-localize with ghrelin and gastrin. Moreover, transmembrane G protein-coupled Receptor 5 (TGR5) agonist decreased pre-proglucagon mRNA expression in SG-1 cells in a concentration-dependent manner, and in vivo experiments showed a decrease in its mRNA levels in the gastric corpus but not in the antrum. This study marks the first report of GLP-1 production in the mouse stomach. Our findings suggest that gastric pre-proglucagon mRNA expression is regulated by a distinct mechanism compared to the L cells of the lower intestine.


Assuntos
Peptídeo 1 Semelhante ao Glucagon , Estômago , Animais , Camundongos , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1 , Intestinos/metabolismo , Proglucagon/metabolismo , RNA Mensageiro/genética , Estômago/metabolismo
3.
Food Funct ; 15(4): 2221-2233, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38318756

RESUMO

Motilin is an important hormonal regulator in the migrating motor complex (MMC). Free fatty acid receptor-1 (FFAR1, also known as GPR40) has been reported to stimulate motilin release in human duodenal organoids. However, how FFAR1 regulates gastric motility in vivo is unclear. This study investigated the role of FFAR1 in the regulation of gastric contractions and its possible mechanism of action using Suncus murinus. Firstly, intragastric administration of oleic acid (C18:1, OA), a natural ligand for FFAR1, stimulated phase II-like contractions, followed by phase III-like contractions in the fasted state, and the gastric emptying rate was accelerated. The administration of GW1100, an FFAR1 antagonist, inhibited the effects of OA-induced gastric contractions. Intravenous infusion of a ghrelin receptor antagonist (DLS) or serotonin 4 (5-HT4) receptor antagonist (GR125487) inhibited phase II-like contractions and prolonged the onset of phase III-like contractions induced by OA. MA-2029, a motilin receptor antagonist, delayed the occurrence of phase III-like contractions. In vagotomized suncus, OA did not induce phase II-like contractions. In addition, OA promoted gastric emptying through a vagal pathway during the postprandial period. However, OA did not directly act on the gastric body to induce contractions in vitro. In summary, this study indicates that ghrelin, motilin, 5-HT, and the vagus nerve are involved in the role of FFAR1 regulating MMC. Our findings provide novel evidence for the involvement of nutritional factors in the regulation of gastric motility.


Assuntos
Ácidos Graxos não Esterificados , Motilidade Gastrointestinal , Humanos , Animais , Ácidos Graxos não Esterificados/farmacologia , Motilina/metabolismo , Motilina/farmacologia , Complexo Mioelétrico Migratório/fisiologia , Estômago/fisiologia , Musaranhos/metabolismo
4.
PLoS One ; 19(1): e0297361, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38277416

RESUMO

Composite materials are popular because of their high performance capabilities, but new material development is time-consuming. To accelerate this process, researchers studying material informatics, an academic discipline combining computational science and material science, have developed less time-consuming approaches for predicting possible material combinations. However, these processes remain problematic because some materials are not suited for them. The limitations of specific candidates for new composites may cause potential new material pairs to be overlooked. To solve this problem, we developed a new method to predict possible composite material pairs by considering more materials than previous techniques. We predicted possible material pairs by conducting link predictions of material word co-occurrence networks while assuming that co-occurring material word pairs in scientific papers on composites were reported as composite materials. As a result, we succeeded in predicting the co-occurrence of material words with high specificity. Nodes tended to link to many other words, generating new links in the created co-occurrence material word network; notably, the number of material words co-occurring with graphene increased rapidly. This phenomenon confirmed that graphene is an attractive composite component. We expect our method to contribute to the accelerated development of new composite materials.

5.
Neurogastroenterol Motil ; 36(2): e14716, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38031349

RESUMO

BACKGROUND: Colonic motility is regulated by various factors along the gut-brain axis; however, detailed mechanisms are unknown. This study aimed to examine the involvement of the autonomic nervous system in colonic motility. Suncus murinus (suncus) is a small laboratory mammal suitable for gastrointestinal motility studies. METHODS: Colonic motility and concomitant feeding and defecation behaviors in vagotomized and reserpine-administered suncus were recorded simultaneously for 24 h. Furthermore, we performed immunohistochemistry on tyrosine hydroxylase (TH) and in situ hybridization on corticotropin-releasing hormone (CRH) in suncus brain. Additionally, we examined c-Fos expression in the brain using immunohistochemistry in conscious suncus with colorectal distension. KEY RESULTS: In vagotomized suncus, clustered giant migrating contractions (GMCs), consisting of strong contractions occurring in a short time, were observed, and the percentage of GMCs without defecation increased. The frequency of GMCs in the reserpine-administered suncus increased during a light period (ZT0-4, 4-8) and decreased during a dark period (ZT16-20, 20-24) compared to a vehicle group. Additionally, the percentage of GMCs without defecation in the reserpine-administered suncus increased. Suncus TH-immunopositive neurons were found in the locus coeruleus (LC), as shown in rodents. In contrast, CRH mRNA-expressing cells were not observed in a region assumed to be the Barrington's nucleus (Bar). Furthermore, colorectal distension in conscious suncus induced c-Fos expression in LC TH neurons. CONCLUSIONS & INFERENCES: Our results suggest that the vagus and sympathetic nerves are not required for induction of GMCs in vivo. However, they are likely to exert a modulatory role in control of GMC frequency in Suncus murinus.


Assuntos
Neoplasias Colorretais , Reserpina , Animais , Nervo Vago/fisiologia , Motilidade Gastrointestinal/fisiologia , Estado de Consciência , Hormônio Liberador da Corticotropina , Mamíferos
6.
Healthcare (Basel) ; 11(23)2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38063618

RESUMO

Studies have indicated that higher numbers of nurses regarding staffing ensure patient safety and a better practice environment. Using citation analysis, this study visualizes the landscape of nurse staffing research over the last two decades to show the overall publication trends, major contributors, and main research topics. We extracted bibliometric information from PubMed from January 2000 to September 2022. After clustering the network, we analyzed each cluster's characteristics by keyword. A total of 2167 papers were considered for analysis, and 14 clusters were created. The analysis showed that the number of papers published per year has been increasing. Researchers from the US, the UK, Canada, Australia, and Belgium have led this field. As the main clusters in nurse staffing research during the past two decades, the following five research settings were identified: nurse outcome and patient outcome research in acute care hospitals, nurse staffing mandate evaluation research, nursing home research, and school nurse research. The first three clusters accounted for more than 80% of the total number of published papers, and this ratio has not changed in the past 20 years. To further develop nurse staffing research globally, evidence from other geographic areas, such as African and Asian countries, and from long-term care or community settings is necessary.

7.
Gen Comp Endocrinol ; 342: 114352, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37517599

RESUMO

In a fasting gastrointestinal tract, a characteristic cyclical rhythmic migrating motor complex (MMC) occur that comprises of three phases: I, II, and III. Among these, phase III contractions propagate from the stomach to the lower intestine in mammals, including humans, dogs, and Suncus murinus (suncus). Apart from the phase III of MMC propagating from the stomach, during the gastric phase II, small intestine-originated strong contractions propagate to the lower small intestine; however, the mechanism of contractions originating in the small intestine has not been clarified. In this study, we aimed to elucidate the role of cholecystokinin (CCK) in small intestinal motility. Administration of sulfated CCK-8 in phase I induced phase II-like contractions in the small intestine, which lasted for approximately 10-20 min and then returned to the baseline, while no change was observed in the stomach. Contractions of small intestine induced by CCK-8 were abolished by lorglumide, a CCK1 receptor antagonist. Gastrin, a ligand for the CCK2 receptor, evoked strong contractions in the stomach, but did not induce contractions in the small intestine. To examine the effect of endogenous CCK on contractions of small intestinal origin, lorglumide was administered during phase II. However, there was no change in the duodenal motility pattern, and strong contractions of small intestinal origin were not abolished by treatment with lorglumide. These results suggest that exogenous CCK stimulates contractions of small intestine via CCK1 receptors, whereas endogenous CCK is not involved in the strong contractions of small intestinal origin.


Assuntos
Motilidade Gastrointestinal , Sincalida , Humanos , Animais , Cães , Sincalida/farmacologia , Complexo Mioelétrico Migratório/fisiologia , Colecistocinina/farmacologia , Estômago , Musaranhos , Receptores da Colecistocinina
8.
Heliyon ; 9(5): e16104, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37234663

RESUMO

Sustainable supply chain networks are critical to the survival of companies in interconnected business ecosystems. Today's rapidly changing market conditions require firms to restructure their network resources flexibly. In this study, we quantitatively investigated how firms' ability to adapt to the turbulent market depends on the stable maintenance and flexible recombination of inter-firm relationships. Using the proposed quantitative index "metabolism," we measured the micro-level dynamics of the supply chain, which represents each firm's average replacement rate of business partners. We applied this index to longitudinal data on the annual transactions of about 10,000 firms from 2007 to 2016 in the Tohoku region, which was affected by the 2011 earthquake and tsunami. The distribution of metabolism values differed across regions and industries, indicating differences in the adaptive capacity of the corresponding firms. We also found the typical balance between supply chain flexibility and stability for successful companies that have survived in the market for a long time. In other words, the relationship between metabolism and duration was not linear but U-shaped, indicating an appropriate metabolism value for survival. These findings provide a deeper understanding of supply chain strategies for adapting to regional market dynamics.

9.
Sci Rep ; 13(1): 4759, 2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36959309

RESUMO

A scientist's choice of research topic affects the impact of their work and future career. While the disparity between nations in scientific information, funding, and facilities has decreased, scientists on the cutting edge of their fields are not evenly distributed across nations. Here, we quantify relative progress in research topics of a nation from the time-series comparison of reference lists from papers, using 71 million published papers from Scopus. We discover a steady leading-following relationship in research topics between Western nations or Asian city-states and others. Furthermore, we find that a nation's share of information-rich scientists in co-authorship networks correlates highly with that nation's progress in research topics. These results indicate that scientists' relationships continue to dominate scientific evolution in the age of open access to information and explain the failure or success of nations' investments in science.

10.
Gen Comp Endocrinol ; 331: 114167, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36402245

RESUMO

Ghrelin is a gut-derived peptide with several physiological functions, including feeding, gastrointestinal motility, and hormonal secretion. Recently, a host defense peptide, liver-expressed antimicrobial peptide-2 (LEAP2), was reported as an endogenous antagonist of growth hormone secretagogue receptor (GHS-R). The physiological relevance of the molecular LEAP2-GHS-R interaction in mammals has been explored; however, studies on non-mammals are limited. Here, we report the identification and functional characterization of ghrelin and its related molecules in Western clawed frog (Xenopus tropicalis), a known model organism. We first identified cDNA encoding X. tropicalis ghrelin and GHS-R. RT-qPCR revealed that ghrelin mRNA expression was most abundant in the stomach. GHS-R mRNA was widely distributed in the brain and peripheral tissues, and a relatively strong signal was observed in the stomach and intestine. In addition, LEAP2 was mainly expressed in intestinal tissues at higher levels than in the liver. In functional analysis, X. tropicalis ghrelin and human ghrelin induced intracellular Ca2+ mobilization with EC50 values in the low nanomolar range in CHO-K1 cells expressing X. tropicalis GHS-R. Furthermore, ghrelin-induced GHS-R activation was antagonized with IC50 values in the nanomolar range by heterologous human LEAP2. We also validated the expression of ghrelin and feeding-related factors under fasting conditions. After 2 days of fasting, no changes in ghrelin mRNA levels were observed in the stomach, but GHS-R mRNA levels were significantly increased, associated with significant downregulation of nucb2. In addition, LEAP2 upregulation was observed in the duodenum. These results provide the first evidence that LEAP2 functions as an antagonist of GHS-R in the anuran amphibian X. tropicalis. It has also been suggested that the ghrelin/GHS-R/LEAP2 system may be involved in energy homeostasis in X. tropicalis.


Assuntos
Grelina , Receptores de Grelina , Animais , Cricetinae , Humanos , Grelina/genética , Grelina/metabolismo , Xenopus/metabolismo , Receptores de Grelina/metabolismo , Cricetulus , Clonagem Molecular , RNA Mensageiro
11.
Heliyon ; 8(9): e10721, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36193537

RESUMO

Comprehensive observations of science, technology, and research policy transactions are important for developing an innovation strategy. We propose a new method that combines the academic landscape and matrix analysis to understand the relationships among activities of three aspects of the technological landscape: science, technology, and research policy. First, we divided academic research into 28 knowledge domains by clustering a citation network of scientific papers. Next, we developed a new matrix classifying them into three groups: "mature technology," "intermediate technology," and "emerging technology." The results showed that research domains in "emerging technology" showed a high rate of patent increase, indicating that they were commercializing rapidly. Finally, we identified the group that each country focused on, and this result reflected the countries' research policies. China and Singapore showed high rates, whereas Japan, France, and Germany had low values. This result reflects countries' research policies and implies that specialty research areas differed by country. As above, our research result implies that academia, industry, and government have paid attention to knowledge domains in "emerging technology" and these are important for creating innovation. A supercapacitor, also known as an electric double layer capacitor or ultracapacitor, was selected as an example in our method. This research could help academic researchers, industrial companies, and policymakers in developing innovation strategies.

12.
PLoS One ; 17(9): e0274253, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36103497

RESUMO

Identifying promising research as early as possible is vital to determine which research deserves investment. Additionally, developing a technology for automatically predicting future research trends is necessary because of increasing digital publications and research fragmentation. In previous studies, many researchers have performed the prediction of scientific indices using specially designed features for each index. However, this does not capture real research trends. It is necessary to develop a more integrated method to capture actual research trends from various directions. Recent deep learning technology integrates different individual models and makes it easier to construct more general-purpose models. The purpose of this paper is to show the possibility of integrating multiple prediction models for scientific indices by network-based representation learning. This paper will conduct predictive analysis of multiple future scientific impacts by embedding a heterogeneous network and showing that a network embedding method is a promising tool for capturing and expressing scientific trends. Experimental results show that the multiple heterogeneous network embedding improved 1.6 points than a single citation network embedding. Experimental results show better results than baseline for the number of indices, including the author h-index, the journal impact factor (JIF), and the Nature Index after three years from publication. These results suggest that distributed representations of a heterogeneous network for scientific papers are the basis for the automatic prediction of scientific trends.

13.
J Phys Chem Lett ; 13(34): 8078-8085, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35997491

RESUMO

Hydrogen-associated electron-doping Mottronics for d-band correlated oxides (e.g., VO2) opens up a new paradigm to regulate the electronic functionality via directly manipulating the orbital configuration and occupancy. Nevertheless, the role of hydrogen in the Mottronic transition of VO2 is yet unclear because opposite orbital reconfigurations toward either the metallic or highly insulating states were both reported. Herein, we demonstrate the root cause for such hydrogen-induced multiple electronic phase transitions by 1H quantification using nuclear reaction analysis. A low hydrogenation temperature is demonstrated to be vital in achieving a large hydrogen concentration (nH ≈ 1022 cm-3) that further enhances the t2g orbital occupancy to trigger electron localizations. In contrast, elevating the hydrogenation temperatures surprisingly reduces nH to ∼1021 cm-3 but forms more stable metallic H0.06VO2. This leads to the recognition of a weaker hydrogen interaction that triggers electron localization within VO2 via Mottronically enhancing the orbital occupancies.

14.
Gen Comp Endocrinol ; 327: 114074, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35700795

RESUMO

Cholecystokinin (CCK) is a peptide hormone mainly secreted by small intestinal endocrine I-cells and functions as a regulator of gallbladder contraction, gastric emptying, gastrointestinal (GI) motility, and satiety. The cellular effects of CCK in these peripheral tissues are predominantly mediated via CCK-A receptors which are found in smooth muscles, enteric neurons, and vagal afferent neurons in humans and animal models. Although various functions of CCK have been reported to be neurally mediated, it can also stimulate contraction via the CCK receptor on the smooth muscle. However, the entire underlying neural and cellular mechanisms involved in CCK-induced GI contractions are not clearly understood. Here, we first determined the cDNA and amino acid sequences of CCK and CCK-A receptor along with the distributions of cck mRNA and CCK-producing cells in house musk shrew (Suncus murinus, the laboratory strain named as suncus) and examined the mechanism of CCK-induced contraction in the GI tract. Mature suncus CCK-8 was identical to other mammalian species tested here, and suncus CCK-A receptor presented high nucleotide and amino acid homology with that of human, dog, mouse, and rat, respectively. Suncus CCK mRNA and CCK-producing cells were found mainly in small intestine and colon. In the organ bath study, CCK-8 induced dose-dependent contractions in the suncus stomach, duodenum, and jejunum, and these contractions were inhibited by atropine and CCK-A receptor antagonist. These results suggest that CCK-8-induced contraction is mediated in the myenteric cholinergic neural network and that CCK-A receptor is partly responsible for CCK-8-induced contractions. This study indicates that suncus is a useful animal model to study the functions of CCK involved in GI motility.


Assuntos
Colecistocinina , Receptor de Colecistocinina A , Musaranhos , Animais , Colecistocinina/genética , Clonagem Molecular , Cães , Motilidade Gastrointestinal , Humanos , Camundongos , Contração Muscular , RNA Mensageiro/genética , Ratos , Receptor de Colecistocinina A/genética , Musaranhos/genética , Sincalida/farmacologia
15.
Front Pharmacol ; 13: 858522, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35462894

RESUMO

Nesfatin-1 is an anorectic peptide expressed in both peripheral tissues and brain areas involved in the regulation of feeding, emotion and emesis. The aim of the present study is to characterize the distribution of NUCB2/nesfatin-1 in Suncus murinus and to investigate the actions of nesfatin-1 to affect gastrointestinal contractility, emesis, food and water intake, and locomotor activity. The deduced amino acid sequence of S. murinus nesfatin-1 using in silico cloning showed high homology with humans and rodents. NUCB2 mRNA was detected throughout the entire brain and in the gastrointestinal tract, including the stomach and gut. Western blot analysis and immunohistochemistry confirmed the expression of nesfatin-1 protein in these regions. The NUCB2 mRNA levels in the hypothalamus, hippocampus and brainstem were significantly decreased, whereas that in the striatum were increased after 24 h starvation compared to ad libitum-fed animals (p < 0.05). In in vitro studies, nesfatin-1 (0.3-1,000 pM) failed to contract or relax the isolated gastric antrum and intestinal segments. In conscious, freely moving animals, intracerebroventricular administration of nesfatin-1 (1-50 pmol) induced emesis (p < 0.05) and suppressed 6-h cumulative food intake (p < 0.05), without affecting the latency to feeding. Nesfatin-1 (25 pmol, i.c.v.) decreased 24-h cumulative food and water intake by 28.3 and 35.4%, respectively (p < 0.01). No significant differences in locomotor activity were observed. In conclusion, NUCB2/nesfatin-1 might be a potent regulator of feeding and emesis in S. murinus. Further studies are required to elucidate the mechanism of actions of this peptide as a mediator linking the brainstem NUCB2/nesfatin-1 to forebrain system.

16.
Gen Comp Endocrinol ; 323-324: 114031, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35331740

RESUMO

Motilin, a peptide hormone consisting of 22 amino acid residues, was identified in the duodenum of pigs in the 1970s. It is known to induce gastrointestinal contractions during the interdigestive state in mammals. Although the motilin gene has been identified in various animal species, it has not been studied in amphibians. Here, we identified the motilin gene in the Japanese fire bellied newt (Cynops pyrrhogaster), and conducted an analysis of tissue distribution, morphological observations, and physiological experiments. The deduced mature newt motilin comprises 22 amino acid residues, like in mammals and birds. The C-terminus of the newt motilin showed high homology with motilin from other species compared to the N-terminus region, which is considered the bioactive site. Motilin mRNA expression in newts was abundant in the upper small intestine, with notably high motilin mRNA expression found in the pancreas. Motilin-producing cells were found in the mucosal layer of the upper small intestine and existed as two cell types: open-and closed-type cells. Motilin-producing cells in the pancreas were also found to produce insulin but not glucagon. Newt motilin stimulated gastric contractions but not in other parts of the intestines in vitro, and motilin-induced gastric contraction was significantly inhibited by treatment with atropine, a muscarinic acetylcholine receptor antagonist. These results indicate that motilin is also present in amphibians, and that its gastrointestinal contractile effects are conserved in mammals, birds, and amphibians. Additionally, we demonstrated for the first time the existence of pancreatic motilin, suggesting that newt motilin has an additional unknown physiological role.


Assuntos
Motilina , Salamandridae , Aminoácidos , Animais , Aves/metabolismo , Motilidade Gastrointestinal , Mamíferos/metabolismo , Motilina/farmacologia , Contração Muscular , RNA Mensageiro/metabolismo , Salamandridae/genética , Salamandridae/metabolismo , Suínos
17.
Neurogastroenterol Motil ; 34(6): e14302, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34846085

RESUMO

BACKGROUND: The aim of this study was to investigate the fundamental mechanisms of colonic motility in the house musk suncus (Suncus murinus) as an established animal model of gut motility. METHODS: To measure gut motility in free-moving conscious suncus, strain gauge force transducers were implanted on the serosa of the colon and gastric body. KEY RESULTS: We recorded diurnal changes in colonic motility and observed the relationship between feeding and colonic motility. Giant migrating contractions (GMCs) of the colon were invariably detected during defecation and tended to increase during the dark period, thereby indicating that colonic motility has a circadian rhythm. Given that GMCs in the suncus were observed immediately after feeding during the dark period, we assume the occurrence of a gastrocolic reflex in suncus, similar to that observed in humans and dogs. We also examined the factors that regulate suncus GMCs. Intravenous administration of 5-HT (100 µg/kg), substance P (10 and 100 µg/kg), calcitonin gene-related peptide (10 µg/kg), and α2 adrenergic receptor antagonist yohimbine (0.5, 1, and 3 mg/kg) induced GMC-like contractions, as did intragastric and intracolonic administration of the transient receptor potential vanilloid 1 agonist, capsaicin (1 mg/kg). CONCLUSIONS & INFERENCES: These results indicate that the fundamental mechanisms of colonic motility in suncus are similar to those in humans and dogs, and we thus propose that suncus could serve as a novel small animal model for studying colonic motility.


Assuntos
Colo , Motilidade Gastrointestinal , Animais , Capsaicina/farmacologia , Cães , Motilidade Gastrointestinal/fisiologia , Musaranhos/fisiologia , Estômago/fisiologia
18.
Neuropeptides ; 90: 102187, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34450431

RESUMO

Ghrelin is a multifunctional gut peptide with a unique structure, which is modified by a medium chain fatty acid at the third serine by ghrelin O-acyl transferase (GOAT). It is well known that the major source of plasma ghrelin is the stomach, but the transcriptional regulation of gastric ghrelin and GOAT is incompletely understood. Here, we studied the involvement of the nuclear receptors REV-ERBα and REV-ERBß on ghrelin and GOAT gene expression in vivo and in vitro. Reverse-transcriptase polymerase chain reaction analysis showed that REV-ERBα and REV-ERBß mRNAs were expressed in the stomach and a stomach-derived ghrelin cell line (SG-1 cells). In vivo experiments with mice revealed the circadian rhythm of ghrelin, GOAT, and REV-ERBs. The peak expression of ghrelin and GOAT mRNAs occurred at Zeitgeber time (ZT) 4, whereas that of REV-ERBα and REV-ERBß was observed at ZT8 and ZT12, respectively. Treatment of SG-1 cells with SR9009, a REV-ERB agonist, led to a significant reduction in ghrelin and GOAT mRNA levels. Overexpression of REV-ERBα and REV-ERBß decreased ghrelin and GOAT mRNA levels in SG-1 cells. In contrast, small-interfering RNA (siRNA)-mediated double-knockdown of REV-ERBα and REV-ERBß in SG-1 cells led to the upregulation in the expression of ghrelin and GOAT mRNAs. These results suggest that REV-ERBs suppress ghrelin and GOAT mRNA expression.


Assuntos
Aciltransferases/biossíntese , Grelina/metabolismo , Grelina/farmacologia , Proteínas de Membrana/biossíntese , Receptor ErbB-2/genética , Estômago/metabolismo , Aciltransferases/genética , Animais , Linhagem Celular , Ritmo Circadiano , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Pirrolidinas/farmacologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Interferente Pequeno/farmacologia , Estômago/efeitos dos fármacos , Tiofenos/farmacologia
19.
Appl Netw Sci ; 6(1): 48, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34226873

RESUMO

Delayed recognition in which innovative discoveries are re-evaluated after a long period has significant implications for scientific progress. The quantitative method to detect delayed recognition is described as the pair of Sleeping Beauty (SB) and its Prince (PR), where SB refers to citation bursts and its PR triggers SB's awakeness calculated based on their citation history. This research provides the methods to extract valid and large SB-PR pairs from a comprehensive Scopus dataset and analyses how PR discovers SB. We prove that the proposed method can extract long-sleep and large-scale SB and its PR best covers the previous multi-disciplinary pairs, which enables to observe delayed recognition. Besides, we show that the high-impact SB-PR pairs extracted by the proposed method are more likely to be located in the same field. This indicates that a hidden SB that your research can awaken may exist closer than you think. On the other hand, although SB-PR pairs are fat-tailed in Beauty Coefficient and more likely to integrate separate fields compared to ordinary citations, it is not possible to predict which citation leads to awake SB using the rarity of citation. There is no easy way to limit the areas where SB-PR pairs occur or detect it early, suggesting that researchers and administrators need to focus on a variety of areas. This research provides comprehensive knowledge about the development of scientific findings that will be evaluated over time.

20.
Mol Biol Rep ; 48(7): 5513-5518, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34302584

RESUMO

Pyridoxine (PN), one of the vitamers of vitamin B6, plays an important role in the maintenance of epidermal function and is used to treat acne and rough skin. Clinical studies have revealed that PN deficiency causes skin problems such as seborrheic dermatitis and stomatitis. However, the detailed effects of PN and its mechanism of action in epidermal function are poorly understood. In this study, we examined the effects of PN on epidermal function in normal human epidermal keratinocytes and found that PN specifically causes an increase in the expression of profilaggrin mRNA, among marker genes of terminal epidermal differentiation. In addition, PN treatment caused an increase in the production of filaggrin protein in a concentration-dependent manner. Treatment with P2x purinoceptor antagonists, namely, pyridoxal phosphate-6-azo (benzene-2,4-disulfonic acid) tetrasodium salt hydrate and TNP-ATP hydrate, induced an increase in the filaggrin protein levels. Moreover, we showed that elevated filaggrin production induced upon PN treatment was suppressed by ATP (known as P2x purinoceptor agonist). This study is the first to report that PN causes an increase in filaggrin transcription and production, and these results suggest that PN-induced filaggrin production may be a useful target as a daily care component in atopic dermatitis, wherein filaggrin levels are specifically reduced.


Assuntos
Proteínas de Filamentos Intermediários/genética , Queratinócitos/metabolismo , Piridoxina/metabolismo , Células Cultivadas , Epiderme/metabolismo , Proteínas Filagrinas , Regulação da Expressão Gênica , Humanos , Piridoxina/farmacologia
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