Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 147
Filter
Add more filters

Country/Region as subject
Publication year range
1.
Genes Dev ; 35(3-4): 234-249, 2021 02 01.
Article in English | MEDLINE | ID: mdl-33446570

ABSTRACT

The physiological functions of many vital tissues and organs continue to mature after birth, but the genetic mechanisms governing this postnatal maturation remain an unsolved mystery. Human pancreatic ß cells produce and secrete insulin in response to physiological cues like glucose, and these hallmark functions improve in the years after birth. This coincides with expression of the transcription factors SIX2 and SIX3, whose functions in native human ß cells remain unknown. Here, we show that shRNA-mediated SIX2 or SIX3 suppression in human pancreatic adult islets impairs insulin secretion. However, transcriptome studies revealed that SIX2 and SIX3 regulate distinct targets. Loss of SIX2 markedly impaired expression of genes governing ß-cell insulin processing and output, glucose sensing, and electrophysiology, while SIX3 loss led to inappropriate expression of genes normally expressed in fetal ß cells, adult α cells, and other non-ß cells. Chromatin accessibility studies identified genes directly regulated by SIX2. Moreover, ß cells from diabetic humans with impaired insulin secretion also had reduced SIX2 transcript levels. Revealing how SIX2 and SIX3 govern functional maturation and maintain developmental fate in native human ß cells should advance ß-cell replacement and other therapeutic strategies for diabetes.


Subject(s)
Cell Differentiation/genetics , Eye Proteins/metabolism , Gene Expression Regulation/genetics , Homeodomain Proteins/metabolism , Insulin-Secreting Cells/cytology , Nerve Tissue Proteins/metabolism , Diabetes Mellitus, Type 2/physiopathology , Humans , Insulin Secretion/genetics , RNA, Small Interfering/metabolism , Transcriptome , Homeobox Protein SIX3
2.
Nature ; 570(7762): 496-499, 2019 06.
Article in English | MEDLINE | ID: mdl-31189951

ABSTRACT

Strong magnetic fields are required in many fields, such as medicine (magnetic resonance imaging), pharmacy (nuclear magnetic resonance), particle accelerators (such as the Large Hadron Collider) and fusion devices (for example, the International Thermonuclear Experimental Reactor, ITER), as well as for other diverse scientific and industrial uses. For almost two decades, 45 tesla has been the highest achievable direct-current (d.c.) magnetic field; however, such a field requires the use of a 31-megawatt, 33.6-tesla resistive magnet inside 11.4-tesla low-temperature superconductor coils1, and such high-power resistive magnets are available in only a few facilities worldwide2. By contrast, superconducting magnets are widespread owing to their low power requirements. Here we report a high-temperature superconductor coil that generates a magnetic field of 14.4 tesla inside a 31.1-tesla resistive background magnet to obtain a d.c. magnetic field of 45.5 tesla-the highest field achieved so far, to our knowledge. The magnet uses a conductor tape coated with REBCO (REBa2Cu3Ox, where RE = Y, Gd) on a 30-micrometre-thick substrate3, making the coil highly compact and capable of operating at the very high winding current density of 1,260 amperes per square millimetre. Operation at such a current density is possible only because the magnet is wound without insulation4, which allows rapid and safe quenching from the superconducting to the normal state5-10. The 45.5-tesla test magnet validates predictions11 for high-field copper oxide superconductor magnets by achieving a field twice as high as those generated by low-temperature superconducting magnets.

3.
Development ; 147(6)2020 03 30.
Article in English | MEDLINE | ID: mdl-32108026

ABSTRACT

Reliance on rodents for understanding pancreatic genetics, development and islet function could limit progress in developing interventions for human diseases such as diabetes mellitus. Similarities of pancreas morphology and function suggest that porcine and human pancreas developmental biology may have useful homologies. However, little is known about pig pancreas development. To fill this knowledge gap, we investigated fetal and neonatal pig pancreas at multiple, crucial developmental stages using modern experimental approaches. Purification of islet ß-, α- and δ-cells followed by transcriptome analysis (RNA-seq) and immunohistology identified cell- and stage-specific regulation, and revealed that pig and human islet cells share characteristic features that are not observed in mice. Morphometric analysis also revealed endocrine cell allocation and architectural similarities between pig and human islets. Our analysis unveiled scores of signaling pathways linked to native islet ß-cell functional maturation, including evidence of fetal α-cell GLP-1 production and signaling to ß-cells. Thus, the findings and resources detailed here show how pig pancreatic islet studies complement other systems for understanding the developmental programs that generate functional islet cells, and that are relevant to human pancreatic diseases.


Subject(s)
Cell Differentiation/genetics , Insulin-Secreting Cells/physiology , Islets of Langerhans/embryology , Islets of Langerhans/growth & development , Swine , Animals , Animals, Newborn , Cells, Cultured , Embryo, Mammalian , Female , Fetus/metabolism , Gene Expression Profiling , Gene Expression Regulation, Developmental , Glucagon-Secreting Cells/cytology , Glucagon-Secreting Cells/physiology , Humans , Islets of Langerhans/cytology , Mice , Organogenesis/genetics , Pregnancy , Swine/embryology , Swine/genetics , Swine/growth & development , Transcription Factors/genetics , Transcription Factors/metabolism , Transcriptome
4.
Mar Drugs ; 21(5)2023 Apr 28.
Article in English | MEDLINE | ID: mdl-37233475

ABSTRACT

This study aimed to elucidate the structural congeners of natural izenamides A, B, and C (1-3) responsible for cathepsin D (CTSD) inhibition. Structurally modified izenamides were synthesized and biologically evaluated, and their biologically important core structures were identified. We confirmed that the natural statine (Sta) unit (3S,4S)-γ-amino-ß-hydroxy acid is a requisite core structure of izenamides for inhibition of CTSD, which is closely related to the pathophysiological roles in numerous human diseases. Interestingly, the statine-incorporated izenamide C variant (7) and 18-epi-izenamide B variant (8) exhibited more potent CTSD-inhibitory activities than natural izenamides.


Subject(s)
Cathepsin D , Protease Inhibitors , Humans , Protease Inhibitors/pharmacology , Protease Inhibitors/chemistry
5.
Proc Natl Acad Sci U S A ; 117(29): 17142-17150, 2020 07 21.
Article in English | MEDLINE | ID: mdl-32636256

ABSTRACT

Gut microbes play diverse roles in modulating host fitness, including longevity; however, the molecular mechanisms underlying their mediation of longevity remain poorly understood. We performed genome-wide screens using 3,792 Escherichia coli mutants and identified 44 E. coli mutants that modulated Caenorhabditis elegans longevity. Three of these mutants modulated C. elegans longevity via the bacterial metabolite methylglyoxal (MG). Importantly, we found that low MG-producing E. coli mutants, Δhns E. coli, extended the lifespan of C. elegans through activation of the DAF-16/FOXO family transcription factor and the mitochondrial unfolded protein response (UPRmt). Interestingly, the lifespan modulation by Δhns did not require insulin/insulin-like growth factor 1 signaling (IIS) but did require TORC2/SGK-1 signaling. Transcriptome analysis revealed that Δhns E. coli activated novel class 3 DAF-16 target genes that were distinct from those regulated by IIS. Taken together, our data suggest that bacteria-derived MG modulates host longevity through regulation of the host signaling pathways rather than through nonspecific damage on biomolecules known as advanced glycation end products. Finally, we demonstrate that MG enhances the phosphorylation of hSGK1 and accelerates cellular senescence in human dermal fibroblasts, suggesting the conserved role of MG in controlling longevity across species. Together, our studies demonstrate that bacteria-derived MG is a novel therapeutic target for aging and aging-associated pathophysiology.


Subject(s)
Caenorhabditis elegans Proteins/metabolism , Caenorhabditis elegans , Forkhead Transcription Factors/metabolism , Longevity/drug effects , Protein Serine-Threonine Kinases/metabolism , Pyruvaldehyde , Animals , Caenorhabditis elegans/drug effects , Caenorhabditis elegans/metabolism , Caenorhabditis elegans/microbiology , Escherichia coli/metabolism , Gastrointestinal Microbiome/physiology , Mechanistic Target of Rapamycin Complex 2/metabolism , Models, Biological , Pyruvaldehyde/metabolism , Pyruvaldehyde/pharmacology , Signal Transduction/drug effects , Transcriptome/genetics
6.
Zygote ; 31(4): 380-385, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37212055

ABSTRACT

In this study, we built on our previous research that discovered that autophagy activated the metaphase I stage during porcine oocytes in vitro maturation. We investigated the relationship between autophagy and oocyte maturation. First, we confirmed whether autophagy was activated differently by different media (TCM199 and NCSU-23) during maturation. Then, we investigated whether oocyte maturation affected autophagic activation. In addition, we examined whether the inhibition of autophagy affected the nuclear maturation rate of porcine oocytes. As for the main experiment, we measured LC3-II levels using western blotting after inhibition of nuclear maturation via cAMP treatment in an in vitro culture to clarify whether nuclear maturation affected autophagy. After autophagy inhibition, we also counted matured oocytes by treating them with wortmannin or a E64d and pepstatin A mixture. Both groups, which had different treatment times of cAMP, showed the same levels of LC3-II, while the maturation rates were about four times higher after cAMP 22 h treatment than that of the 42 h treatment group. This indicated that neither cAMP nor nuclear status affected autophagy. Autophagy inhibition during in vitro oocyte maturation with wortmannin treatment reduced oocyte maturation rates by about half, while autophagy inhibition by the E64d and pepstatin A mixture treatment did not significantly affect the oocyte maturation. Therefore, wortmannin itself, or the autophagy induction step, but not the degradation step, is involved in the oocyte maturation of porcine oocytes. Overall, we propose that oocyte maturation does not stand upstream of autophagy activation, but autophagy may exist upstream of oocyte maturation.


Subject(s)
In Vitro Oocyte Maturation Techniques , Oocytes , Animals , Swine , Wortmannin/pharmacology , Wortmannin/metabolism , Oocytes/physiology , Metaphase , Autophagy
7.
Bioorg Chem ; 122: 105716, 2022 05.
Article in English | MEDLINE | ID: mdl-35303621

ABSTRACT

The discovery of small molecules that regulate specific neuronal phenotypes is important for the development of new therapeutic candidates for neurological diseases. Estrogen-related receptor γ (ERRγ), an orphan nuclear receptor widely expressed in the central nervous system (CNS), is closely related to the regulation of neuronal metabolism and differentiation. We previously reported that upregulation of ERRγ could enhance dopaminergic neuronal phenotypes in the neuroblastoma cell line, SH-SY5Y. In this study, we designed and synthesized a series of new ERRγ agonists using the X-ray crystal structure of the GSK4716-bound ERRγ complex and known synthetic ligands. Our new ERRγ agonists exhibited increased transcriptional activities of ERRγ. In addition, our molecular docking results supported the experimental findings for ERRγ agonistic activity of the potent analogue, 5d. Importantly, 5d not only enhanced the expression of dopaminergic neuronal-specific molecules, TH and DAT but also activated the relevant signaling events, such as the CREB-mediated signaling pathway. The results of the present study may provide useful clues for the development of novel ERRγ agonists for neurological diseases related to the dopaminergic nervous system.


Subject(s)
Dopaminergic Neurons , Receptors, Estrogen , Dopaminergic Neurons/metabolism , Molecular Docking Simulation , Phenotype , Receptors, Estrogen/metabolism , Up-Regulation
8.
Eur Heart J ; 42(41): 4264-4276, 2021 11 01.
Article in English | MEDLINE | ID: mdl-34279605

ABSTRACT

AIMS: Non-compaction cardiomyopathy is a devastating genetic disease caused by insufficient consolidation of ventricular wall muscle that can result in inadequate cardiac performance. Despite being the third most common cardiomyopathy, the mechanisms underlying the disease, including the cell types involved, are poorly understood. We have previously shown that endothelial cell-specific deletion of the chromatin remodeller gene Ino80 results in defective coronary vessel development that leads to ventricular non-compaction in embryonic mouse hearts. We aimed to identify candidate angiocrines expressed by endocardial and endothelial cells (ECs) in wildtype and LVNC conditions in Tie2Cre;Ino80fl/fltransgenic embryonic mouse hearts, and test the effect of these candidates on cardiomyocyte proliferation and maturation. METHODS AND RESULTS: We used single-cell RNA-sequencing to characterize endothelial and endocardial defects in Ino80-deficient hearts. We observed a pathological endocardial cell population in the non-compacted hearts and identified multiple dysregulated angiocrine factors that dramatically affected cardiomyocyte behaviour. We identified Col15a1 as a coronary vessel-secreted angiocrine factor, downregulated by Ino80-deficiency, that functioned to promote cardiomyocyte proliferation. Furthermore, mutant endocardial and endothelial cells up-regulated expression of secreted factors, such as Tgfbi, Igfbp3, Isg15, and Adm, which decreased cardiomyocyte proliferation and increased maturation. CONCLUSIONS: These findings support a model where coronary endothelial cells normally promote myocardial compaction through secreted factors, but that endocardial and endothelial cells can secrete factors that contribute to non-compaction under pathological conditions.


Subject(s)
Endothelial Cells , Myocytes, Cardiac , Animals , Endocardium , Heart Ventricles , Mice , Myocardium
9.
Molecules ; 27(19)2022 Oct 07.
Article in English | MEDLINE | ID: mdl-36235197

ABSTRACT

This paper reports a concise and scalable method for the synthesis of the phytoestrogen 7,2'-dihydroxy-4',5'-dimethoxyisoflavanone 1 via an optimized synthetic route. Compound 1 was readily obtained in 11 steps and 11% overall yield on a gram scale from commercially available 3,4-dimethoxyphenol. The key features of the synthesis include the construction of the deoxybenzoin unit through a sequence of Claisen rearrangement, oxidative cleavage, and aryllithium addition and the efficient synthesis of the isoflavanone architecture from highly functionalized 2-hydroxyketone.


Subject(s)
Phytoestrogens , Phytoestrogens/pharmacology , Stereoisomerism
10.
Pharmacol Res ; 165: 105423, 2021 03.
Article in English | MEDLINE | ID: mdl-33434621

ABSTRACT

Brain derived neurotrophic factor (BDNF) promotes maturation of dopaminergic (DAergic) neurons in the midbrain and positively regulates their maintenance and outgrowth. Therefore, understanding the mechanisms regulating the BDNF signaling pathway in DAergic neurons may help discover potential therapeutic strategies for neuropsychological disorders associated with dysregulation of DAergic neurotransmission. Because estrogen-related receptor gamma (ERRγ) is highly expressed in both the fetal nervous system and adult brains during DAergic neuronal differentiation, and it is involved in regulating the DAergic neuronal phenotype, we asked in this study whether ERRγ ligand regulates BDNF signaling and subsequent DAergic neuronal phenotype. Based on the X-ray crystal structures of the ligand binding domain of ERRγ, we designed and synthesized the ERRγ agonist, (E)-4-hydroxy-N'-(4-(phenylethynyl)benzylidene)benzohydrazide (HPB2) (Kd value, 8.35 µmol/L). HPB2 increased BDNF mRNA and protein levels, and enhanced the expression of the BDNF receptor tropomyosin receptor kinase B (TrkB) in human neuroblastoma SH-SY5Y, differentiated Lund human mesencephalic (LUHMES) cells, and primary ventral mesencephalic (VM) neurons. HPB2-induced upregulation of BDNF was attenuated by GSK5182, an antagonist of ERRγ, and siRNA-mediated ERRγ silencing. HPB2-induced activation of extracellular-signal-regulated kinase (ERK) and phosphorylation of cAMP-response element binding protein (CREB) was responsible for BDNF upregulation in SH-SY5Y cells. HPB2 enhanced the DAergic neuronal phenotype, namely upregulation of tyrosine hydroxylase (TH) and DA transporter (DAT) with neurite outgrowth, both in SH-SY5Y and primary VM neurons, which was interfered by the inhibition of BDNF-TrkB signaling, ERRγ knockdown, or blockade of ERK activation. HPB2 also upregulated BDNF and TH in the striatum and induced neurite elongation in the substantia nigra of mice brain. In conclusion, ERRγ activation regulated BDNF expression and the subsequent DAergic neuronal phenotype in neuronal cells. Our results might provide new insights into the mechanism underlying the regulation of BDNF expression, leading to novel therapeutic strategies for neuropsychological disorders associated with DAergic dysregulation.


Subject(s)
Brain-Derived Neurotrophic Factor/biosynthesis , Dopaminergic Neurons/metabolism , Estradiol Congeners/pharmacology , Membrane Glycoproteins/biosynthesis , Receptor, trkB/biosynthesis , Receptors, Estrogen/metabolism , Up-Regulation/physiology , Animals , Brain-Derived Neurotrophic Factor/chemistry , Cell Line, Tumor , Dopaminergic Neurons/drug effects , Estradiol Congeners/chemistry , Female , Humans , Ligands , Male , Membrane Glycoproteins/chemistry , Mice , Mice, Inbred C57BL , Microsomes, Liver/drug effects , Microsomes, Liver/metabolism , Phenotype , Pregnancy , Protein Structure, Secondary , Protein Structure, Tertiary , Rats , Rats, Sprague-Dawley , Receptor, trkB/chemistry , Receptors, Estrogen/chemistry , Up-Regulation/drug effects
11.
Bioorg Chem ; 116: 105398, 2021 11.
Article in English | MEDLINE | ID: mdl-34628222

ABSTRACT

The first total syntheses of isocorniculatolide B, corniculatolide B, and corniculatolide C, consisting of isomeric corniculatolide skeletons, have been accomplished in a divergent manner. The key features of the synthesis involve the construction of diaryl ether linkages by nucleophilic aromatic substitution, installation of a C14-substituted alkyl side chain via a sequence of Baeyer-Villiger reaction and Claisen rearrangement, and efficient construction of corniculatolide and isocorniculatolide frameworks, including 17-membered (exterior) macrolactone skeletons from a versatile diaryl ether intermediate by Mitsunobu macrolactonization. Moreover, we prepared the structural congeners of isomeric corniculatolides via diverted total synthesis approach including desmethyl analogues and related dimeric macrolides. The anti-inflammatory activities of the synthesized natural products, analogues and synthetic intermediates were also investigated. In particular, corniculatolide B significantly inhibited the protein expression of COX-2 and the mRNA expressions of TNF-α, IL-1ß and IL-6 by inhibiting of NF-κB signaling in intestinal epithelial cells induced by lipopolysaccharide treatment. It also significantly inhibited the promoter activity and the phosphorylation of subunits p50 and p65 of NF-κB to the same extent as Bay 11-7082, a potent IκB kinase inhibitor. These results suggest that corniculatolide B might have therapeutic potential in inflammatory bowel disease via NF-κB signaling pathway.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Lactones/pharmacology , Macrolides/pharmacology , NF-kappa B/antagonists & inhibitors , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemical synthesis , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Cell Line , Dose-Response Relationship, Drug , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Lactones/chemical synthesis , Macrolides/chemical synthesis , Molecular Structure , NF-kappa B/metabolism , Rats , Structure-Activity Relationship
12.
Molecules ; 25(21)2020 Nov 06.
Article in English | MEDLINE | ID: mdl-33172169

ABSTRACT

Pyrimidine is a privileged scaffold in many synthetic compounds exhibiting diverse pharmacological activities, and is used for therapeutic applications in a broad spectrum of human diseases. In this study, we prepared a small set of pyrimidine libraries based on the structure of two hit compounds that were identified through the screening of an in-house library in order to identify an inhibitor of anoctamin 1 (ANO1). ANO1 is amplified in various types of human malignant tumors, such as head and neck, parathyroid, and gastrointestinal stromal tumors, as well as in breast, lung, and prostate cancers. After initial screening and further structure optimization, we identified Aa3 as a dose-dependent ANO1 blocker. This compound exhibited more potent anti-cancer activity in the NCI-H460 cell line, expressing high levels of ANO1 compared with that in A549 cells that express low levels of ANO1. Our results open a new direction for the development of small-molecule ANO1 blockers composed of a pyrimidine scaffold and a nitrogen-containing heterocyclic moiety, with drug-like properties.


Subject(s)
Anoctamin-1/antagonists & inhibitors , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Neoplasm Proteins/antagonists & inhibitors , Pyrimidines/chemistry , Animals , Anoctamin-1/metabolism , Antineoplastic Agents/chemical synthesis , Cell Line, Tumor , Cell Survival/drug effects , Dose-Response Relationship, Drug , Drug Design , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Neoplasm Proteins/metabolism , Pyrimidines/pharmacology , Rats
13.
Molecules ; 25(9)2020 May 08.
Article in English | MEDLINE | ID: mdl-32397326

ABSTRACT

Despite numerous reports on the beneficial effects of catechin or epicatechin contained in tea and cacao extract on human health, a conclusive and precise molecular mechanism has not been elucidated. Metabolism of chemical compounds in gut microbiota recently gained significant attention, and extensive studies have been devoted in this field. In conjunction with these results, our group focused on the anti-inflammatory effects of both enantiomers of DHPV (5-(3',4'-dihydroxyphenyl)-γ-valerolactone), produced in the intestine by microbiota metabolism, on IEC-6 cells. Divergent and efficient enantioselective synthesis of (S)- and (R)-DHPV was efficiently achieved by cross-metathesis and Sharpless asymmetric dihydroxylation as a key reaction for four steps in 16% and 14% overall yields, respectively. The anti-inflammatory effects of two enantiomers were tested on IEC-6 cells, and we found that (S)-DHPV was more active than (R)-DHPV. This result implicates that the metabolite produced in the gut has beneficial effects on IEC-6 cells of rat intestines, and the chirality of the metabolite is important for its anti-inflammatory activity. This also provided information for the future discovery of novel small molecular therapeutics for the treatment of inflammatory bowel disease.


Subject(s)
Anti-Inflammatory Agents , Inflammatory Bowel Diseases/drug therapy , Intestinal Mucosa/metabolism , Animals , Anti-Inflammatory Agents/chemical synthesis , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/pharmacology , Cell Line , Inflammatory Bowel Diseases/metabolism , Inflammatory Bowel Diseases/pathology , Intestinal Mucosa/pathology , Lactones/chemical synthesis , Lactones/chemistry , Lactones/pharmacology , Rats
14.
EMBO J ; 34(19): 2424-40, 2015 Oct 01.
Article in English | MEDLINE | ID: mdl-26206584

ABSTRACT

Primary cilia start forming within the G1 phase of the cell cycle and continue to grow as cells exit the cell cycle (G0). They start resorbing when cells re-enter the cell cycle (S phase) and are practically invisible in mitosis. The mechanisms by which cilium biogenesis and disassembly are coupled to the cell cycle are complex and not well understood. We previously identified the centrosomal phosphoprotein NDE1 as a negative regulator of ciliary length and showed that its levels inversely correlate with ciliogenesis. Here, we identify the tumor suppressor FBW7 (also known as FBXW7, CDC4, AGO, or SEL-10) as the E3 ligase that mediates the destruction of NDE1 upon entry into G1. CDK5, a kinase active in G1/G0, primes NDE1 for FBW7-mediated recognition. Cells depleted of FBW7 or CDK5 show enhanced levels of NDE1 and a reduction in ciliary length, which is corrected in cells depleted of both FBW7 or CDK5 and NDE1. These data show that cell cycle-dependent mechanisms can control ciliary length through a CDK5-FBW7-NDE1 pathway.


Subject(s)
Cell Cycle Proteins/metabolism , Cell Cycle/physiology , Cyclin-Dependent Kinase 5/metabolism , F-Box Proteins/metabolism , Microtubule-Associated Proteins/metabolism , Proteolysis , Ubiquitin-Protein Ligases/metabolism , Ubiquitination/physiology , Animals , BALB 3T3 Cells , Cell Cycle Proteins/genetics , Cilia/genetics , Cilia/metabolism , Cyclin-Dependent Kinase 5/genetics , F-Box Proteins/genetics , F-Box-WD Repeat-Containing Protein 7 , HEK293 Cells , Humans , Mice , Microtubule-Associated Proteins/genetics , Signal Transduction/physiology , Ubiquitin-Protein Ligases/genetics
15.
Biochem Biophys Res Commun ; 515(4): 725, 2019 Aug 06.
Article in English | MEDLINE | ID: mdl-31239030

ABSTRACT

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the authors. The authors have indicated that Fig. 1D data originated from another source not specified in the article. They also indicated image duplication in Fig. 1A and B. The authors of this article would like to apologize to all affected parties.

16.
FASEB J ; 32(1): 111-122, 2018 01.
Article in English | MEDLINE | ID: mdl-28855280

ABSTRACT

Human intestinal organoids (hIOs) derived from human pluripotent stem cells (hPSCs) have immense potential as a source of intestines. Therefore, an efficient system is needed for visualizing the stage of intestinal differentiation and further identifying hIOs derived from hPSCs. Here, 2 fluorescent biosensors were developed based on human induced pluripotent stem cell (hiPSC) lines that stably expressed fluorescent reporters driven by intestine-specific gene promoters Krüppel-like factor 5 monomeric Cherry (KLF5mCherry) and intestine-specific homeobox enhanced green fluorescence protein (ISXeGFP). Then hIOs were efficiently induced from those transgenic hiPSC lines in which mCherry- or eGFP-expressing cells, which appeared during differentiation, could be identified in intact living cells in real time. Reporter gene expression had no adverse effects on differentiation into hIOs and proliferation. Using our reporter system to screen for hIO differentiation factors, we identified DMH1 as an efficient substitute for Noggin. Transplanted hIOs under the kidney capsule were tracked with fluorescence imaging (FLI) and confirmed histologically. After orthotopic transplantation, the localization of the hIOs in the small intestine could be accurately visualized using FLI. Our study establishes a selective system for monitoring the in vitro differentiation and for tracking the in vivo localization of hIOs and contributes to further improvement of cell-based therapies and preclinical screenings in the intestinal field.-Jung, K. B., Lee, H., Son, Y. S., Lee, J. H., Cho, H.-S., Lee, M.-O., Oh, J.-H., Lee, J., Kim, S., Jung, C.-R., Kim, J., Son, M.-Y. In vitro and in vivo imaging and tracking of intestinal organoids from human induced pluripotent stem cells.


Subject(s)
Induced Pluripotent Stem Cells/cytology , Intestines/cytology , Organoids/cytology , Animals , Biosensing Techniques , Cell Differentiation/genetics , Cell Line , Computer Systems , Genes, Reporter , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Heterografts , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Humans , Induced Pluripotent Stem Cells/metabolism , Induced Pluripotent Stem Cells/transplantation , Intestinal Mucosa/metabolism , Intestine, Small/cytology , Intestine, Small/metabolism , Kruppel-Like Transcription Factors/genetics , Kruppel-Like Transcription Factors/metabolism , Luminescent Proteins/genetics , Luminescent Proteins/metabolism , Mice , Mice, Inbred NOD , Mice, Knockout , Mice, SCID , Organoids/metabolism , Real-Time Polymerase Chain Reaction , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Red Fluorescent Protein
17.
Compr Psychiatry ; 89: 67-77, 2019 02.
Article in English | MEDLINE | ID: mdl-30597426

ABSTRACT

BACKGROUND: Despite heterogeneity of older people in suicidal behavior, research identifying characteristics by age groups is scarce. We examined baseline features of older community-dwelling suicidal ideators by dichotomized age groups and the 6-month trajectory of their suicidal ideation along with its related psychopathology. Predictors of suicidal ideation within each group were investigated. METHODS: Older community-dwelling suicidal ideators enrolled in the Korean Cohort for the Model Predicting a Suicide and Suicide-related Behavior study were subdivided into the "young-old (65-74 years)" and "old-old (≥75 years)" group. Baseline, 1-, and 6-month assessments were compared. Within each group, multiple regression analysis using rating scales (Patient Health Questionnaire-9, Beck Anxiety Inventory, Alcohol Use Disorders Identification Test, Stress Questionnaire for Korean National Health and Nutrition Examination Survey-Short Form, and Social Relationships Scale) was conducted to identify predictors of suicidal ideation measured with the intensity subscale of the Columbia-Suicide Severity Rating Scale. Two-way repeated-measures analysis of variance (RM-ANOVA) was used to compare changes in suicidal ideation, depression, anxiety between age groups over time, and one-way RM-ANOVA to examine changes within each age group. RESULTS: Among 29 "young-old" and 53 "old-old" ideators, the latter were less likely to be receiving psychiatric treatment (odds ratio [OR] = 4.065) and make suicide attempts (OR = 2.874), whereas the former revealed greater levels of anxiety and stress. Baseline depression and stress in the "young-old" group and the "old-old" group, respectively, predicted the intensity of suicidal ideation at both baseline and 1-month assessments. No significant age group x time interactions on suicidal ideation and depression were found. However, within each age group, both suicidal ideation and depression significantly decreased only during the first month with no further improvement. CONCLUSION: We speculate cautiously that more attention may need to be paid to the "old-old" ideators in the evaluation of psychiatric issues and for referral to psychiatrists. To decrease suicidal ideation, tailored approaches involving proactive, timely management of depression in the "young-old" and interventions focusing on stress reduction in the "old-old," would be helpful.


Subject(s)
Age Factors , Independent Living/psychology , Suicidal Ideation , Aged , Aged, 80 and over , Analysis of Variance , Anxiety/psychology , Depression/psychology , Female , Follow-Up Studies , Humans , Longitudinal Studies , Male , Nutrition Surveys , Suicide, Attempted/psychology , Surveys and Questionnaires
18.
Compr Psychiatry ; 88: 29-38, 2019 01.
Article in English | MEDLINE | ID: mdl-30468986

ABSTRACT

BACKGROUND: The Korean Cohort for the Model Predicting a Suicide and Suicide-related Behavior (K-COMPASS) study is a prospective, naturalistic, observational cohort study, aiming to identify predictors of suicide attempt and suicide characteristics in the Korean suicidal population. The findings intend to contribute to a thorough understanding of suicidal phenomena and development of suicide prevention guidelines. The present cross-section study examines the study rationale, methodology, and baseline characteristics of the participants. METHODS: Participants were enrolled via the hospital and community gateways, establishing the hospital-based cohort (HC) and community-based cohort (CC), respectively. Baseline assessment was conducted on sociodemographic, clinical, diagnostic, and psychopathological aspects. The Columbia-Suicide Severity Rating Scale was used to investigate suicidality. RESULTS: A total of 800 suicidal people aged 15 years or older were enrolled from 8 university hospitals and 8 community mental health welfare centers (CMHWCs), among whom 480 (60%) were suicidal ideators and 320 (40%) were attempters. The ideators comprised 207 CC and 273 HC participants, whereas the attempters, 34 CC and 286 HC participants. Despite their lower severity in some measures, including suicidal ideation, compared with their HC counterparts, the CC participants within each group of ideators or attempters presented clinically significant psychopathology. Moreover, alcohol use problems and past suicide attempt were more likely to be found in CC participants. Only 11.1% to 21.6% of the participants in each of the four groups (defined by the cohorts and the ideators/attempters) were on any type of psychiatric treatment. CONCLUSIONS: Suicidal visitors to CMHWCs need to be as closely monitored as suicidal patients in university hospitals, especially considering their association with problem drinking and past suicide attempt. A cautious assumption is that the high suicide rate in Korea might be partly attributable to the low proportion of patients receiving psychiatric services.


Subject(s)
Alcoholism/epidemiology , Alcoholism/psychology , Suicidal Ideation , Suicide, Attempted/psychology , Adolescent , Adult , Aged , Aged, 80 and over , Alcoholism/diagnosis , Cohort Studies , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Prospective Studies , Republic of Korea/epidemiology , Suicide, Attempted/trends , Young Adult
19.
Int J Mol Sci ; 20(9)2019 May 10.
Article in English | MEDLINE | ID: mdl-31083413

ABSTRACT

Arazyme, a metalloprotease from the spider Nephila clavata, exerts hepatoprotective activity in CCL4-induced acute hepatic injury. This study investigated the hepatoprotective effects in high-fat diet (HFD)-induced non-alcoholic fatty liver disease-like C57BL/6J mice. The mice were randomly divided into four groups (n = 10/group): the normal diet group, the HFD group, the arazyme group (HFD with 0.025% arazyme), and the milk thistle (MT) group (HFD with 0.1% MT). Dietary supplementation of arazyme for 13 weeks significantly lowered plasma triglyceride (TG) and non-esterified fatty acid levels. Suppression of HFD-induced hepatic steatosis in the arazyme group was caused by the reduced hepatic TG and total cholesterol (TC) contents. Arazyme supplementation decreased hepatic lipogenesis-related gene expression, sterol regulatory element-binding transcription protein 1 (Srebf1), fatty acid synthase (Fas), acetyl-CoA carboxylase 1 (Acc1), stearoyl-CoA desaturase-1 (Scd1), Scd2, glycerol-3-phosphate acyltransferase (Gpam), diacylglycerol O-acyltransferase 1 (Dgat1), and Dgat2. Arazyme directly reduced palmitic acid (PA)-induced TG accumulation in HepG2 cells. Arazyme suppressed macrophage infiltration and tumor necrosis factor α (Tnfa), interleukin-1ß (Il1b), and chemokine-ligand-2 (Ccl2) expression in the liver, and inhibited secretion of TNFα and expression of inflammatory mediators, Tnfa, Il1b, Ccl2, Ccl3, Ccl4, and Ccl5, in PA-induced RAW264.7 cells. Arazyme effectively protected hepatic steatosis and steatohepatitis by inhibiting SREBP-1-mediated lipid accumulation and macrophage-mediated inflammation.


Subject(s)
Metalloproteases/therapeutic use , Non-alcoholic Fatty Liver Disease/drug therapy , Animals , Biomarkers/blood , Body Weight , Diet, High-Fat , Disease Models, Animal , Gene Expression Regulation , Glucose Tolerance Test , Hep G2 Cells , Humans , Inflammation/pathology , Lipogenesis/genetics , Macrophages/metabolism , Male , Mice , Mice, Inbred C57BL , Non-alcoholic Fatty Liver Disease/blood , Organ Size , Palmitic Acid , RAW 264.7 Cells
20.
Molecules ; 24(24)2019 Dec 08.
Article in English | MEDLINE | ID: mdl-31817984

ABSTRACT

The unexpected rearrangement of N-allyl-2-phenyl-4,5-dihydrooxazole-4-carboxamides in the presence of LiHMDS has been found. The key features are: (1) the net reaction consisted of 1,3-migration of the N-allyl group, (2) the rearrangement produced a congested aza-quaternary carbon center, (3) both cyclic and acyclic substrates underwent the unexpected rearrangement to afford products in moderate to high yields, and (4) the reaction seemed to be highly stereoselective. In addition, a plausible mechanism has been discussed.


Subject(s)
Allyl Compounds/chemistry , Carbon/chemistry , Molecular Structure , Stereoisomerism
SELECTION OF CITATIONS
SEARCH DETAIL