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Protein arginylation is a critical regulator of a variety of biological processes. The ability to uncover the global arginylation pattern and its associated signaling pathways would enable us to identify novel disease targets. Here, we report the development of a tool able to capture the N-terminal arginylome. This tool, termed R-catcher, is based on the ZZ domain of p62, which was previously shown to bind N-terminally arginylated proteins. Mutating the ZZ domain enhanced its binding specificity and affinity for Nt-Arg. R-catcher pulldown coupled to LC-MS/MS led to the identification of 59 known and putative arginylated proteins. Among these were a subgroup of novel ATE1-dependent arginylated ER proteins that are linked to diverse biological pathways, including cellular senescence and vesicle-mediated transport as well as diseases, such as Amyotrophic Lateral Sclerosis and Alzheimer's disease. This study presents the first molecular tool that allows the unbiased identification of arginylated proteins, thereby unlocking the arginylome and provide a new path to disease biomarker discovery.
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Aminoaciltransferasas/metabolismo , Arginina/metabolismo , Retículo Endoplásmico/metabolismo , Vectores Genéticos/genética , Proteínas de la Membrana/metabolismo , Procesamiento Proteico-Postraduccional , Aminoaciltransferasas/química , Aminoaciltransferasas/genética , Arginina/química , Arginina/genética , Células HeLa , Humanos , Proteínas de la Membrana/genética , Especificidad por SustratoRESUMEN
UBR box E3 ligases, also called N-recognins, are integral components of the N-degron pathway. Representative N-recognins include UBR1, UBR2, UBR4, and UBR5, and they bind destabilizing N-terminal residues, termed N-degrons. Understanding the molecular bases of their substrate recognition and the biological impact of the clearance of their substrates on cellular signaling pathways can provide valuable insights into the regulation of these pathways. This review provides an overview of the current knowledge of the binding mechanism of UBR box N-recognin/N-degron interactions and their roles in signaling pathways linked to G-protein-coupled receptors, apoptosis, mitochondrial quality control, inflammation, and DNA damage. The targeting of these UBR box N-recognins can provide potential therapies to treat diseases such as cancer and neurodegenerative diseases.
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Apoptosis , Daño del ADN , Inflamación/patología , Receptores Acoplados a Proteínas G/metabolismo , Transducción de Señal , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Humanos , Inflamación/metabolismoRESUMEN
Atopic dermatitis (AD) is a chronic inflammatory skin disease whose prevalence is increasing worldwide. Filaggrin (FLG) is essential for the development of the skin barrier, and its genetic mutations are major predisposing factors for AD. In this study, we developed a convenient and practical method to detect FLG mutations in AD patients using peptide nucleic acid (PNA) probes labelled with fluorescent markers for rapid analysis. Fluorescence melting curve analysis (FMCA) precisely identified FLG mutations based on the distinct difference in the melting temperatures of the wild-type and mutant allele. Moreover, PNA probe-based FMCA easily and accurately verified patient samples with both heterozygote and homozygote FLG mutations, providing a high-throughput method to reliable screen AD patients. Our method provides a convenient, rapid and accurate diagnostic tool to identify potential AD patients allowing for early preventive treatment, leading to lower incidence rates of AD, and reducing total healthcare expenses.
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Análisis Mutacional de ADN/métodos , Sondas de ADN , Dermatitis Atópica/diagnóstico , Dermatitis Atópica/genética , Proteínas de Filamentos Intermediarios/genética , Alelos , Estudios de Casos y Controles , Proteínas Filagrina , Fluorescencia , Heterocigoto , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Homocigoto , Humanos , Mutación , Ácidos Nucleicos de Péptidos/genética , Temperatura de TransiciónRESUMEN
Coumarin, a phenolic compound, is a secondary metabolite produced by plants such as Tanga and Lime. Coumarin derivatives were prepared via Pechmann condensation. In this study, we performed in vitro and in vivo experiments to determine the antimicrobial and gut immune-regulatory functions of coumarin derivatives. For the in vitro antimicrobial activity assay, coumarin derivatives C1 and C2 were selected based on their pathogen-killing activity against various pathogenic microbes. We further demonstrated that the selected coumarin derivatives disrupted bacterial cell membranes. Next, we examined the regulatory function of the coumarin derivatives in gut inflammation using an infectious colitis model. In an in vivo infectious colitis model, administration of selected C1 coumarin derivatives reduced pathogen loads, the number of inflammatory immune cells (Th1 cells and Th17 cells), and inflammatory cytokine levels (IL-6 and IL-1b) in the intestinal tissue after pathogen infection. In addition, we found that the administration of C1 coumarin derivatives minimized abnormal gut microbiome shift-driven pathogen infection. Potential pathogenic gut microbes, such as Enterobacteriaceae and Staphylococcaceae, were increased by pathogen infection. However, this pathogenic microbial expansion was minimized and beneficial bacteria, such as Ligilactobacillus and Limosilactobacillus, increased with C1 coumarin derivative treatment. Functional gene enrichment assessment revealed that the relative abundance of genes associated with lipid and nucleotide metabolism was reduced by pathogen infection; however, this phenomenon was not observed in C1 coumarin derivative-treated animals. Collectively, our data suggest that C1 coumarin derivative is effective antibacterial agents that minimize pathogen-induced gut inflammation and abnormal gut microbiome modulation through their antibacterial activity.
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Antibacterianos , Colitis , Cumarinas , Modelos Animales de Enfermedad , Microbioma Gastrointestinal , Cumarinas/farmacología , Microbioma Gastrointestinal/efectos de los fármacos , Animales , Colitis/microbiología , Colitis/tratamiento farmacológico , Antibacterianos/farmacología , Ratones , Citocinas/metabolismo , Bacterias/efectos de los fármacos , Bacterias/clasificación , Ratones Endogámicos C57BL , Inflamación/tratamiento farmacológico , Células Th17/efectos de los fármacos , Células Th17/inmunología , Células TH1/inmunología , Células TH1/efectos de los fármacos , MasculinoRESUMEN
The gut microbiota plays a pivotal role in metabolic disorders, notably type 2 diabetes mellitus (T2DM). In this study, we investigated the synergistic potential of combining the effects of Bifidobacterium longum NBM7-1 (CKD1) with anti-diabetic medicines, Lobeglitazoneâ (LO), Sitagliptinâ (SI), and Metforminâ (Met), to alleviate hyperglycemia in a diabetic mouse model. CKD1 effectively mitigated insulin resistance, hepatic steatosis, and enhanced pancreatic ß-cell function, as well as fortifying gut-tight junction integrity. In the same way, SI-CKD1 and Met- CKD1 synergistically improved insulin sensitivity and prevented hepatic steatosis, as evidenced by the modulation of key genes associated with insulin signaling, ß-oxidation, gluconeogenesis, adipogenesis, and inflammation by qRT-PCR. The comprehensive impact on modulating gut microbiota composition was observed, particularly when combined with Metforminâ. This combination induced an increase in the abundance of Rikenellaceae and Alistipes related negatively to the T2DM incidence while reducing the causative species of Cryptosporangium, Staphylococcaceae, and Muribaculaceae. These alterations intervene in gut microbiota metabolites to modulate the level of butyrate, indole-3-acetic acid, propionate, and inflammatory cytokines and to activate the IL-22 pathway. However, it is meaningful that the combination of B. longum NBM7-1(CKD1) reduced the medicines' dose to the level of the maximal inhibitory concentrations (IC50). This study advances our understanding of the intricate relationship between gut microbiota and metabolic disorders. We expect this study to contribute to developing a prospective therapeutic strategy modulating the gut microbiota.
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Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Resistencia a la Insulina , Metformina , Ratones , Animales , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Regulación hacia Arriba , Diabetes Mellitus Experimental/tratamiento farmacológico , Metformina/farmacología , Metformina/uso terapéuticoRESUMEN
Protein arginylation is a unique and under-explored posttranslational modification, which governs many biological functions and the fate of affected proteins. Since ATE1 was discovered in 1963, a central tenet of protein arginylation is that arginylated proteins are destined for proteolysis. However, recent studies have shown that protein arginylation controls not only the half-life of a protein but also various signaling pathways. Here, we introduce a novel molecular tool to elucidate protein arginylation. This new tool, termed R-catcher, is derived from the ZZ domain of p62/sequestosome-1, an N-recognin of the N-degron pathway. The ZZ domain, which has been shown to strongly bind N-terminal arginine, has been modified at specific residues to increase specificity and affinity for N-terminal arginine. R-catcher is a powerful analysis tool allowing researchers to capture the cellular arginylation patterns under various stimuli and conditions, thereby identifying potential therapeutic targets in numerous diseases.
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Aminoaciltransferasas , Aminoaciltransferasas/química , Procesamiento Proteico-Postraduccional , Proteolisis , Proteínas/metabolismo , Arginina/metabolismoRESUMEN
Background: Neuromyelitis optica spectrum disorder (NMOSD) diagnostic criteria for inflammatory demyelinating central nervous system diseases included symptomatic narcolepsy; however, no relevant case-control studies exist. We aimed to examine the relationship among cerebrospinal fluid orexin-A (CSF-OX) levels, cataplexy and diencephalic syndrome; determine risk factors for low-and-intermediate CSF-OX levels (≤200 pg/mL) and quantify hypothalamic intensity using MRI. Methods: This ancillary retrospective case-control study included 50 patients with hypersomnia and 68 controls (among 3000 patients) from Akita University, the University of Tsukuba and community hospitals (200 facilities). Outcomes were CSF-OX level and MRI hypothalamus-to-caudate-nucleus-intensity ratio. Risk factors were age, sex, hypersomnolence and MRI hypothalamus-to-caudate-nucleus-intensity ratio >130%. Logistic regression was performed for the association between the risk factors and CSF-OX levels ≤200 pg/mL. Results: The hypersomnia group (n=50) had significantly more cases of NMOSD (p<0.001), diencephalic syndrome (p=0.006), corticosteroid use (p=0.011), hypothalamic lesions (p<0.023) and early treatment (p<0.001). No cataplexy occurred. In the hypersomnia group, the median CSF-OX level was 160.5 (IQR 108.4-236.5) pg/mL and median MRI hypothalamus-to-caudate-nucleus-intensity ratio was 127.6% (IQR 115.3-149.1). Significant risk factors were hypersomnolence (adjusted OR (AOR) 6.95; 95% CI 2.64 to 18.29; p<0.001) and MRI hypothalamus-to-caudate-nucleus-intensity ratio >130% (AOR 6.33; 95% CI 1.18 to 34.09; p=0.032). The latter was less sensitive in predicting CSF-OX levels ≤200 pg/mL. Cases with MRI hypothalamus-to-caudate-nucleus-intensity ratio >130% had a higher rate of diencephalic syndrome (p<0.001, V=0.59). Conclusions: Considering orexin as reflected by CSF-OX levels and MRI hypothalamus-to-caudate-nucleus-intensity ratio may help diagnose hypersomnia with diencephalic syndrome.
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Non-rapid eye movement (NREM) sleep is tightly homeostatically regulated and essential for survival. In the electroencephalogram (EEG), oscillations in the delta (0.5-4 Hz) range are prominent during NREM sleep. These delta oscillations are, to date, the best indicator for homeostatic sleep regulation; they are increased after prolonged waking and fade during NREM sleep. The precise mechanisms underlying sleep homeostasis and the generation of EEG delta oscillations are still being investigated. Activity-dependent neuronal calcium influx has been hypothesized to play an important role in generating delta oscillations and might be involved in downstream signaling that mediates sleep function. Dihydropyridine blockers of L-type voltage-gated calcium channels (VGCCs) are in wide clinical use to treat hypertension and other cardiovascular disorders and are readily blood-brain-barrier penetrant. We therefore, wanted to investigate their potential effects on EEG delta oscillation and homeostatic NREM sleep regulation in freely behaving mice. In vivo two-photon imaging of cortical neurons showed larger spontaneous calcium transients in NREM sleep compared to waking. Application of the dihydropyridine calcium blocker nicardipine significantly reduced cortical calcium transients without affecting the generation of delta oscillations. Nicardipine also did not affect EEG delta oscillations over 24 h following application. The time spent in NREM sleep and NREM episode duration was also not affected. Thus, acute block of calcium entry through L-type VGCCs does not interfere with EEG delta oscillations or their homeostatic regulation, despite prior evidence from calcium channel knockout mice.
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INTRODUCTION: Current hypnotic agents have next-day residual effects. The new orexin antagonist, suvorexant, has little muscle relaxation effect on the physical and cognitive function in the following morning and daytime. In this study, the effects of suvorexant, zolpidem, ramelteon and placebo in elderly subjects were evaluated. METHODS: Six men and eight women aged 63-75 years received a single tablet and lights were then turned off. Subjects were instructed to sleep from 23:00-6:00 with an interruption from 4:00-4:30 for evaluations. Suvorexant 10 mg, zolpidem 5 mg, ramelteon 4 mg or placebo was administered single time in a randomized, double-blind and crossover design with a one-week drug holiday in between each drug. Measures of objective parameters and subjective ratings were obtained every 2 h from 4:00 to 16:00. RESULT: No subjects showed serious side effects from physical observations and vital sign checks before and after hypnotics were taken. During the first sleep period, the REM sleep time with suvorexant was especially longer than that with zolpidem. During the second sleep period, suvorexant had shorter sleep latency and longer stage2 sleep time than ramelteon and zolpidem, respectively. During the whole entire sleep, the REM sleep time with suvorexant was longer than zolpidem and placebo. For the body sway test with closed eye, the main effects of the medicines and zolpidem were significantly better than suvorexant and ramelteon. CONCLUSION: The changes of physical and cognitive functions in healthy elderly after taking hypnotics were not remarkable. Therefore, these three hypnotics maybe appropriate for the elderly people with insomnia for single-time low dose administration.
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Hipnóticos y Sedantes , Anciano , Azepinas , Método Doble Ciego , Femenino , Humanos , Hipnóticos y Sedantes/efectos adversos , Indenos , Masculino , Orexinas , Triazoles , ZolpidemRESUMEN
Controlled ovarian hyperstimulation (COH) is routinely used in the in vitro fertilization and embryo transfer (IVF-ET) cycles to increase the number of retrieved mature oocytes. However, the relationship between repeated COH and ovarian function is still controversial. Therefore, we investigated whether repeated ovarian stimulation affects ovarian aging and function, including follicular development, autophagy, and apoptosis in follicles. Ovarian hyperstimulation in mice was induced by intraperitoneal injection with pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG). Mice subjected to ovarian stimulation once were used as a control group and 10 times as an experimental group. Repeated injections with PMSG and hCG significantly reduced the number of primary follicles compared to a single injection. The number of secondary and antral follicles increased slightly, while the number of corpus luteum increased significantly with repeated injections. On the other hand, repeated injections did not affect apoptosis in follicles associated with follicular atresia. The expression of autophagy-related genes Atg5, Atg12, LC3B, and Beclin1, cell proliferation-related genes mTOR, apoptosis-related genes Fas, and FasL was not significantly different between the two groups. In addition, the expression of the aging-related genes Dnmt1, Dnmt3a, and AMH were also not significantly different. In this study, we demonstrated that repeated ovarian stimulation in mice affects follicular development, but not autophagy, apoptosis, aging in ovary. These results suggest that repetition of COH in the IVF-ET cycle may not result in ovarian aging, such as a decrease in ovarian reserve in adult women.
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PURPOSE: Multiple sleep latency test (MSLT) is performed as objective assessment of sleepiness, on the following day after polysomnography (PSG). In most clinics, patients are required to stay for 2 days. However, if patients have chronic sleep debt before the examination, even if they get adequate nocturnal sleep during the initial PSG, their sleep debt would not be fully resolved, affecting MSLT results. This may lead to improper administration of psycho-stimulant medication. To clarify the sleep debt for the patients who showed short sleep latencies, we compared the mean sleep latencies of MSLTs. METHODS: Twelve hypersomnolent males, who underwent MSLTs (1st MSLT with 1 night and 2nd MSLT with more than 3 nights), were enrolled. We selected these cases based on the longer total sleep time on PSG night compared to the mean total sleep time on pre-examination sleep logs and shortened sleep latencies on PSG. To evaluate the effect of the sleep debt for the patients who showed short sleep latencies, we extended their hospitalization or re-hospitalized them. RESULTS: The mean sleep latency of 1st MSLT was 5.8 minutes and that of 2nd was 13.9 minutes (P < .001). Among these 12 cases, 5 cases altered from short to normal sleep latencies at the 2nd MSLT. These 5 cases were prevented from over-diagnoses by the extension of evaluations. CONCLUSIONS: The sleep debt may produce false-positive results when patients are examined by standard PSG and MSLT. Accumulation of sleep debt will cause shortened sleep latencies in the following nights. Patients should be advised to extend their hospitalization before PSG and MSLT to reduce the chronic sleep debt for accurate diagnosis of hypersomnia.