1
|
Abstract
Using optimized, asymmetric radiofrequency (RF) pulses for slice selection, the authors demonstrate that stimulated echo acquisition mode (STEAM) localization with ultra-short echo time (1 ms) is possible. Water suppression was designed to minimize sensitivity to B1 inhomogeneity using a combination of 7 variable power RF pulses with optimized relaxation delays (VAPOR). Residual water signal was well below the level of most observable metabolites. Contamination by the signals arising from outside the volume of interest was minimized by outer volume saturation using a series of hyperbolic secant RF pulses, resulting in a sharp volume definition. In conjunction with FASTMAP shimming (Gruetter Magn Reson Med 1993;29: 804-811), the short echo time of 1 msec resulted in highly resolved in vivo 1H nuclear magnetic resonance spectra. In rat brain the water linewidths of 11-13 Hz and metabolite singlet linewidths of 8-10 Hz were measured in 65 microl volumes. Very broad intense signals (delta v(1/2) > 1 kHz), as expected from membranes, for example, were not observed, suggesting that their proton T2 are well below 1 msec. The entire chemical shift range of 1H spectrum was observable, including resolved resonances from alanine, aspartate, choline group, creatine, GABA, glucose, glutamate, glutamine, myo-inositol, lactate, N-acetylaspartate, N-acetylaspartylglutamate, phosphocreatine, and taurine. At 9.4 T, peaks close to the water were observed, including the H-1 of alpha-D-glucose at 5.23 ppm and a tentative H-1 resonance of glycogen at 5.35 ppm.
Collapse
|
|
26 |
767 |
2
|
Choi IY, Piccio L, Childress P, Bollman B, Ghosh A, Brandhorst S, Suarez J, Michalsen A, Cross AH, Morgan TE, Wei M, Paul F, Bock M, Longo VD. A Diet Mimicking Fasting Promotes Regeneration and Reduces Autoimmunity and Multiple Sclerosis Symptoms. Cell Rep 2016; 15:2136-2146. [PMID: 27239035 DOI: 10.1016/j.celrep.2016.05.009] [Citation(s) in RCA: 334] [Impact Index Per Article: 37.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 02/20/2016] [Accepted: 04/26/2016] [Indexed: 01/20/2023] Open
Abstract
Dietary interventions have not been effective in the treatment of multiple sclerosis (MS). Here, we show that periodic 3-day cycles of a fasting mimicking diet (FMD) are effective in ameliorating demyelination and symptoms in a murine experimental autoimmune encephalomyelitis (EAE) model. The FMD reduced clinical severity in all mice and completely reversed symptoms in 20% of animals. These improvements were associated with increased corticosterone levels and regulatory T (Treg) cell numbers and reduced levels of pro-inflammatory cytokines, TH1 and TH17 cells, and antigen-presenting cells (APCs). Moreover, the FMD promoted oligodendrocyte precursor cell regeneration and remyelination in axons in both EAE and cuprizone MS models, supporting its effects on both suppression of autoimmunity and remyelination. We also report preliminary data suggesting that an FMD or a chronic ketogenic diet are safe, feasible, and potentially effective in the treatment of relapsing-remitting multiple sclerosis (RRMS) patients (NCT01538355).
Collapse
|
Research Support, U.S. Gov't, Non-P.H.S. |
9 |
334 |
3
|
Lim JH, Lee JC, Lee YH, Choi IY, Oh YK, Kim HS, Park JS, Kim WK. Simvastatin prevents oxygen and glucose deprivation/reoxygenation-induced death of cortical neurons by reducing the production and toxicity of 4-hydroxy-2E-nonenal. J Neurochem 2006; 97:140-50. [PMID: 16515553 DOI: 10.1111/j.1471-4159.2006.03715.x] [Citation(s) in RCA: 234] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Lipid membrane peroxidation is highly associated with neuronal death in various neurodegenerative diseases including cerebral stroke. Here, we report that simvastatin decreases oxygen and glucose deprivation (OGD)/reoxygenation-evoked neuronal death by inhibiting the production and cytoxicity of 4-hydroxy-2E-nonenal (HNE), the final product of lipid peroxidation. Simvastatin markedly decreased the OGD/reoxygenation-evoked death of cortical neurons. OGD/reoxygenation increased the intracellular HNE level mostly in neuronal cells, not glial cells. Simvastatin decreased the intracellular level of HNE in neuronal cells exposed to OGD/reoxygenation. We further found that HNE induced the cytotoxicity in neuronal cells and synergistically increased the N-methyl-D-aspartate (NMDA) receptor-mediated excitotoxicity. Simvastatin largely blocked the NMDA neurotoxicity potentiated by HNE. However, simvastatin did not alter the NMDA-evoked calcium influx in the absence or presence of HNE. HNE inhibited the activity of nuclear factor-kappa B (NF-kappaB), and the cytotoxicity of HNE was in good correlation with inactivation of NF-kappaB. Simvastatin reversed the inhibition of NF-kappaB activity induced by OGD/reoxygenation or HNE. The neuroprotection by simvastatin was significantly attenuated by various NF-kappaB inhibitors, implying that simvastatin inhibits the cytotoxicity of HNE at least in part by maintaining the activity of NF-kappaB. Further understanding of the neuroprotective mechanism of simvastatin may provide a therapeutic strategy for oxidative stress-related neurodegenerative diseases.
Collapse
|
Research Support, Non-U.S. Gov't |
19 |
234 |
4
|
Lee G, Ramirez CN, Kim H, Zeltner N, Liu B, Radu C, Bhinder B, Kim YJ, Choi IY, Mukherjee-Clavin B, Djaballah H, Studer L. Large-scale screening using familial dysautonomia induced pluripotent stem cells identifies compounds that rescue IKBKAP expression. Nat Biotechnol 2012; 30:1244-8. [PMID: 23159879 PMCID: PMC3711177 DOI: 10.1038/nbt.2435] [Citation(s) in RCA: 176] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Accepted: 10/30/2012] [Indexed: 01/12/2023]
Abstract
Patient-specific induced pluripotent stem cells (iPSCs) represent a novel system for modeling human genetic disease and could develop into a key drug discovery platform. We recently reported disease-specific phenotypes in iPSCs from familial dysautonomia (FD) patients. FD is a rare but fatal genetic disorder affecting neural crest lineages. Here we demonstrate the feasibility of performing a primary screen in FD-iPSC derived neural crest precursors. Out of 6,912 compounds tested we characterized 8 hits that rescue expression of IKBKAP, the gene responsible for FD. One of those hits, SKF-86466, is shown to induce IKBKAP transcription via modulation of intracellular cAMP levels and PKA dependent CREB phosphorylation. SKF-86466 also rescues IKAP protein expression and the disease-specific loss of autonomic neuron marker expression. Our data implicate alpha-2 adrenergic receptor activity in regulating IKBKAP expression and demonstrate that small molecule discovery in an iPSC-based disease model can identify candidate drugs for potential therapeutic intervention.
Collapse
|
Research Support, Non-U.S. Gov't |
13 |
176 |
5
|
Choi IY, Lim H, Estrellas K, Mula J, Cohen TV, Zhang Y, Donnelly CJ, Richard JP, Kim YJ, Kim H, Kazuki Y, Oshimura M, Li HL, Hotta A, Rothstein J, Maragakis N, Wagner KR, Lee G. Concordant but Varied Phenotypes among Duchenne Muscular Dystrophy Patient-Specific Myoblasts Derived using a Human iPSC-Based Model. Cell Rep 2016; 15:2301-2312. [PMID: 27239027 DOI: 10.1016/j.celrep.2016.05.016] [Citation(s) in RCA: 126] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Revised: 10/08/2015] [Accepted: 04/30/2016] [Indexed: 12/11/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) remains an intractable genetic disease. Althogh there are several animal models of DMD, there is no human cell model that carries patient-specific DYSTROPHIN mutations. Here, we present a human DMD model using human induced pluripotent stem cells (hiPSCs). Our model reveals concordant disease-related phenotypes with patient-dependent variation, which are partially reversed by genetic and pharmacological approaches. Our "chemical-compound-based" strategy successfully directs hiPSCs into expandable myoblasts, which exhibit a myogenic transcriptional program, forming striated contractile myofibers and participating in muscle regeneration in vivo. DMD-hiPSC-derived myoblasts show disease-related phenotypes with patient-to-patient variability, including aberrant expression of inflammation or immune-response genes and collagens, increased BMP/TGFβ signaling, and reduced fusion competence. Furthermore, by genetic correction and pharmacological "dual-SMAD" inhibition, the DMD-hiPSC-derived myoblasts and genetically corrected isogenic myoblasts form "rescued" multi-nucleated myotubes. In conclusion, our findings demonstrate the feasibility of establishing a human "DMD-in-a-dish" model using hiPSC-based disease modeling.
Collapse
|
Research Support, Non-U.S. Gov't |
9 |
126 |
6
|
Choi IY, Lee SP, Kim SG, Gruetter R. In vivo measurements of brain glucose transport using the reversible Michaelis-Menten model and simultaneous measurements of cerebral blood flow changes during hypoglycemia. J Cereb Blood Flow Metab 2001; 21:653-63. [PMID: 11488534 DOI: 10.1097/00004647-200106000-00003] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Glucose is the major substrate that sustains normal brain function. When the brain glucose concentration approaches zero, glucose transport across the blood-brain barrier becomes rate limiting for metabolism during, for example, increased metabolic activity and hypoglycemia. Steady-state brain glucose concentrations in alpha-chloralose anesthetized rats were measured noninvasively as a function of plasma glucose. The relation between brain and plasma glucose was linear at 4.5 to 30 mmol/L plasma glucose, which is consistent with the reversible Michaelis-Menten model. When the model was fitted to the brain glucose measurements, the apparent Michaelis-Menten constant, Kt, was 3.3 +/- 1.0 mmol/L, and the ratio of the maximal transport rate relative to CMRglc, Tmax/CMRglc, was 2.7 +/- 0.1. This Kt is comparable to the authors' previous human data, suggesting that glucose transport kinetics in humans and rats are similar. Cerebral blood flow (CBF) was simultaneously assessed and constant above 2 mmol/L plasma glucose at 73 +/- 6 mL 100 g(-1) min(-1). Extrapolation of the reversible Michaelis-Menten model to hypoglycemia correctly predicted the plasma glucose concentration (2.1 +/- 0.6 mmol/L) at which brain glucose concentrations approached zero. At this point, CBF increased sharply by 57% +/- 22%, suggesting that brain glucose concentration is the signal that triggers defense mechanisms aimed at improving glucose delivery to the brain during hypoglycemia.
Collapse
|
|
24 |
124 |
7
|
Rho MJ, Choi IY, Lee J. Predictive factors of telemedicine service acceptance and behavioral intention of physicians. Int J Med Inform 2014; 83:559-71. [PMID: 24961820 DOI: 10.1016/j.ijmedinf.2014.05.005] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2012] [Revised: 05/23/2014] [Accepted: 05/23/2014] [Indexed: 01/27/2023]
Abstract
PURPOSE Despite the proliferation of telemedicine technology, telemedicine service acceptance has been slow in actual healthcare settings. The purpose of this research is to develop a theoretical model for explaining the predictive factors influencing physicians' willingness to use telemedicine technology to provide healthcare services. METHODS We developed the Telemedicine Service Acceptance model based on the technology acceptance model (TAM) with the inclusion of three predictive constructs from the previously published telemedicine literature: (1) accessibility of medical records and of patients as clinical factors, (2) self-efficacy as an individual factor and (3) perceived incentives as regulatory factors. A survey was conducted, and structural equation modeling was applied to evaluate the empirical validity of the model and causal relationships within the model using the data collected from 183 physicians. RESULTS Our results confirmed the validity of the original TAM constructs: the perceived usefulness of telemedicine directly impacted the behavioral intention to use it, and the perceived ease of use directly impacted both the perceived usefulness and the behavioral intention to use it. In addition, new predictive constructs were found to have ramifications on TAM variables: the accessibility of medical records and of patients directly impacted the perceived usefulness of telemedicine, self-efficacy had a significant positive effect on both the perceived ease of use and the perceived usefulness of telemedicine, and perceived incentives were found to be important with respect to the intention to use telemedicine technology. CONCLUSIONS This study demonstrated that the Telemedicine Service Acceptance model was feasible and could explain the acceptance of telemedicine services by physicians. These results identified important factors for increasing the involvement of physicians in telemedicine practice.
Collapse
|
Research Support, Non-U.S. Gov't |
11 |
109 |
8
|
Kim YJ, Lim H, Li Z, Oh Y, Kovlyagina I, Choi IY, Dong X, Lee G. Generation of multipotent induced neural crest by direct reprogramming of human postnatal fibroblasts with a single transcription factor. Cell Stem Cell 2014; 15:497-506. [PMID: 25158936 DOI: 10.1016/j.stem.2014.07.013] [Citation(s) in RCA: 106] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Revised: 06/19/2014] [Accepted: 07/29/2014] [Indexed: 12/22/2022]
Abstract
Neural crest (NC) generates diverse lineages including peripheral neurons, glia, melanocytes, and mesenchymal derivatives. Isolating multipotent human NC has proven challenging, limiting our ability to understand NC development and model NC-associated disorders. Here, we report direct reprogramming of human fibroblasts into induced neural crest (iNC) cells by overexpression of a single transcription factor, SOX10, in combination with environmental cues including WNT activation. iNC cells possess extensive capacity for migration in vivo, and single iNC clones can differentiate into the four main NC lineages. We further identified a cell surface marker for prospective isolation of iNCs, which was used to generate and purify iNCs from familial dysautonomia (FD) patient fibroblasts. FD-iNC cells displayed defects in cellular migration and alternative mRNA splicing, providing insights into FD pathogenesis. Thus, this study provides an accessible platform for studying NC biology and disease through rapid and efficient reprogramming of human postnatal fibroblasts.
Collapse
|
Research Support, Non-U.S. Gov't |
11 |
106 |
9
|
Kim Y, Jeong JE, Cho H, Jung DJ, Kwak M, Rho MJ, Yu H, Kim DJ, Choi IY. Personality Factors Predicting Smartphone Addiction Predisposition: Behavioral Inhibition and Activation Systems, Impulsivity, and Self-Control. PLoS One 2016; 11:e0159788. [PMID: 27533112 PMCID: PMC4988723 DOI: 10.1371/journal.pone.0159788] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 07/08/2016] [Indexed: 01/08/2023] Open
Abstract
The purpose of this study was to identify personality factor-associated predictors of smartphone addiction predisposition (SAP). Participants were 2,573 men and 2,281 women (n = 4,854) aged 20–49 years (Mean ± SD: 33.47 ± 7.52); participants completed the following questionnaires: the Korean Smartphone Addiction Proneness Scale (K-SAPS) for adults, the Behavioral Inhibition System/Behavioral Activation System questionnaire (BIS/BAS), the Dickman Dysfunctional Impulsivity Instrument (DDII), and the Brief Self-Control Scale (BSCS). In addition, participants reported their demographic information and smartphone usage pattern (weekday or weekend average usage hours and main use). We analyzed the data in three steps: (1) identifying predictors with logistic regression, (2) deriving causal relationships between SAP and its predictors using a Bayesian belief network (BN), and (3) computing optimal cut-off points for the identified predictors using the Youden index. Identified predictors of SAP were as follows: gender (female), weekend average usage hours, and scores on BAS-Drive, BAS-Reward Responsiveness, DDII, and BSCS. Female gender and scores on BAS-Drive and BSCS directly increased SAP. BAS-Reward Responsiveness and DDII indirectly increased SAP. We found that SAP was defined with maximal sensitivity as follows: weekend average usage hours > 4.45, BAS-Drive > 10.0, BAS-Reward Responsiveness > 13.8, DDII > 4.5, and BSCS > 37.4. This study raises the possibility that personality factors contribute to SAP. And, we calculated cut-off points for key predictors. These findings may assist clinicians screening for SAP using cut-off points, and further the understanding of SA risk factors.
Collapse
|
Journal Article |
9 |
103 |
10
|
Li B, Wang X, Choi IY, Wang YC, Liu S, Pham AT, Moon H, Smith DJ, Rao DS, Boldin MP, Yang L. miR-146a modulates autoreactive Th17 cell differentiation and regulates organ-specific autoimmunity. J Clin Invest 2017; 127:3702-3716. [PMID: 28872459 DOI: 10.1172/jci94012] [Citation(s) in RCA: 103] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 07/18/2017] [Indexed: 12/14/2022] Open
Abstract
Autoreactive CD4 T cells that differentiate into pathogenic Th17 cells can trigger autoimmune diseases. Therefore, investigating the regulatory network that modulates Th17 differentiation may yield important therapeutic insights. miR-146a has emerged as a critical modulator of immune reactions, but its role in regulating autoreactive Th17 cells and organ-specific autoimmunity remains largely unknown. Here, we have reported that miR-146a-deficient mice developed more severe experimental autoimmune encephalomyelitis (EAE), an animal model of human multiple sclerosis (MS). We bred miR-146a-deficient mice with 2D2 T cell receptor-Tg mice to generate 2D2 CD4 T cells that are deficient in miR-146a and specific for myelin oligodendrocyte glycoprotein (MOG), an autoantigen in the EAE model. miR-146a-deficient 2D2 T cells induced more severe EAE and were more prone to differentiate into Th17 cells. Microarray analysis revealed enhancements in IL-6- and IL-21-induced Th17 differentiation pathways in these T cells. Further study showed that miR-146a inhibited the production of autocrine IL-6 and IL-21 in 2D2 T cells, which in turn reduced their Th17 differentiation. Thus, our study identifies miR-146a as an important molecular brake that blocks the autocrine IL-6- and IL-21-induced Th17 differentiation pathways in autoreactive CD4 T cells, highlighting its potential as a therapeutic target for treating autoimmune diseases.
Collapse
|
Journal Article |
8 |
103 |
11
|
Pfeuffer J, Tkác I, Choi IY, Merkle H, Ugurbil K, Garwood M, Gruetter R. Localized in vivo 1H NMR detection of neurotransmitter labeling in rat brain during infusion of [1-13C] D-glucose. Magn Reson Med 1999; 41:1077-83. [PMID: 10371437 DOI: 10.1002/(sici)1522-2594(199906)41:6<1077::aid-mrm1>3.0.co;2-#] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Resolved localized nuclear magnetic resonance (NMR) signals of 1H bound to 13C label in the carbon positions of glutamate C4, C3 and glutamine C4, C3, as well as in aspartate C3, lactate C3, alanine C3, gamma-aminobutyric acid C3, and glucose C1 were simultaneously observed in spectra obtained from rat brain in vivo. Time-resolved label incorporation was measured with a new adiabatic carbon editing and decoupling (ACED) single-voxel stimulated echo acquisition mode (STEAM) sequence. Adiabatic carbon broadband decoupling of 12 kHz bandwidth was achieved in vivo, which decoupled the entire 13C spectrum at 9.4 T. Resonances from N-acetyl-aspartate and creatine were also detected, consistent with natural-abundance 13C levels. These results emphasize the potential of 1H NMR for following complex biochemical pathways in localized areas of resting rat brain as well as during focal activation using infusions of 13C-labeled glucose.
Collapse
|
|
26 |
94 |
12
|
Choi IY, Tkác I, Ugurbil K, Gruetter R. Noninvasive measurements of [1-(13)C]glycogen concentrations and metabolism in rat brain in vivo. J Neurochem 1999; 73:1300-8. [PMID: 10461925 DOI: 10.1046/j.1471-4159.1999.0731300.x] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Using a specific 13C NMR localization method, 13C label incorporation into the glycogen C1 resonance was measured while infusing [1-(13)C]glucose in intact rats. The maximal concentration of [1-(13)C]glycogen was 5.1 +/- 0.6 micromol g(-1) (mean +/- SE, n = 8). During the first 60 min of acute hyperglycemia, the rate of 13C label incorporation (synthase flux) was 2.3 +/- 0.7 micromol g(-1) h(-1) (mean +/- SE, n = 9 rats), which was higher (p < 0.01) than the rate of 0.49 +/- 0.14 micromol g(-1) h(-1) measured > or = 2 h later. To assess whether the incorporation of 13C label was due to turnover or net synthesis, the infusion was continued in seven rats with unlabeled glucose. The rate of 13C label decline (phosphorylase flux) was lower (0.33 +/- 0.10 micromol g(-1) h(-1)) than the initial rate of label incorporation (p < 0.01) and appeared to be independent of the duration of the preceding infusion of [1-(13)C]glucose (p > 0.05 for correlation). The results implied that net glycogen synthesis of approximately 3 micromol g(-1) had occurred, similar to previous reports. When infusing unlabeled glucose before [1-(13)C]glucose in three studies, the rate of glycogen C1 accumulation was 0.46 +/- 0.08 micromol g(-1) h(-1). The results suggest that steady-state glycogen turnover rates during hyperglycemia are approximately 1% of glucose consumption.
Collapse
|
|
26 |
86 |
13
|
Choi IY, Lee C, Longo VD. Nutrition and fasting mimicking diets in the prevention and treatment of autoimmune diseases and immunosenescence. Mol Cell Endocrinol 2017; 455:4-12. [PMID: 28137612 PMCID: PMC5862044 DOI: 10.1016/j.mce.2017.01.042] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 01/25/2017] [Accepted: 01/25/2017] [Indexed: 02/04/2023]
Abstract
Complex and coordinated signals are necessary to initiate and sustain the activation, proliferation, and differentiation of lymphocytes. These signals, which are known to determine T-cell fate and function, also depend on the metabolic state of the organism. Recent studies indicate that both the type and levels of nutrients can influence the generation, survival and function of lymphocytes and therefore can affect several autoimmune diseases. Here, we review the dysregulation of lymphocytes during autoimmunity and aging, the mechanisms associated with loss of immune function, and how fasting mimicking diets and other dietary interventions affect autoimmunity and immunosenescence.
Collapse
|
Review |
8 |
83 |
14
|
Oz G, Tkác I, Charnas LR, Choi IY, Bjoraker KJ, Shapiro EG, Gruetter R. Assessment of adrenoleukodystrophy lesions by high field MRS in non-sedated pediatric patients. Neurology 2005; 64:434-41. [PMID: 15699371 DOI: 10.1212/01.wnl.0000150906.52208.e7] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Early detection of white matter lesions in childhood-onset cerebral adrenoleukodystrophy (ALD) is important as hematopoietic cell transplantation (HCT), currently the only effective treatment, is beneficial only if performed early in the disease course. OBJECTIVE To establish reliable biochemical markers of cerebral disease progression in patients with ALD to aid in treatment planning. METHODS The authors used proton magnetic resonance spectroscopy (MRS) in combination with LCModel analysis to quantify brain metabolites in small volumes (3 to 16 mL) in the occipital and frontal white matter and the splenium of the corpus callosum of 17 unsedated patients and 26 healthy volunteers (adult n = 21, age-matched n = 5) at 4 tesla. RESULTS Absolute concentrations of 12 metabolites were reliably determined, seven of which were established as markers of lesion development. Among these, creatine and choline containing compounds were the weakest markers while N-acetylaspartate, glutamine, and lipids + lactate were the strongest. The large extent of changes in the markers enabled detection of early neurochemical changes in lesion formation prior to detection of abnormalities by conventional MRI. Concentrations of a number of metabolites were also significantly different between normal appearing white matter of patients and controls indicating biochemical alterations in the absence of cerebral disease. Neurochemical improvements following HCT were measured in six patients. CONCLUSIONS The progression of adrenoleukodystrophy, as well as effectiveness of its treatment, can be assessed with high precision using high field 1H magnetic resonance spectroscopy in individual patients without the need for sedation.
Collapse
|
Research Support, U.S. Gov't, P.H.S. |
20 |
79 |
15
|
Koopman FA, Tang MW, Vermeij J, de Hair MJ, Choi IY, Vervoordeldonk MJ, Gerlag DM, Karemaker JM, Tak PP. Autonomic Dysfunction Precedes Development of Rheumatoid Arthritis: A Prospective Cohort Study. EBioMedicine 2016; 6:231-237. [PMID: 27211565 PMCID: PMC4856742 DOI: 10.1016/j.ebiom.2016.02.029] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 02/02/2016] [Accepted: 02/16/2016] [Indexed: 12/11/2022] Open
Abstract
Background Heart rate variability (HRV) is a validated method to establish autonomic nervous system (ANS) activity. Rheumatoid arthritis (RA) is accompanied by ANS imbalance. We hypothesized that ANS dysfunction may precede the development of RA, which would suggest that it plays a role in its etiopathogenesis. Methods First, we assessed HRV parameters in supine (resting) and upright (active) position in healthy subjects (HS, n = 20), individuals at risk of developing arthritis (AR subjects, n = 50) and RA patients (RA, n = 20). Next, we measured resting heart rate (RHR), a parasympathetic HRV parameter, in an independent prospective cohort of AR subjects (n = 45). We also evaluated expression levels of the parasympathetic nicotinic acetylcholine receptor type 7 (α7nAChR) on circulating monocytes. Findings Both AR subjects (68 beats per minute (bpm), interquartile range (IQR) 68–73) and RA patients (68 bpm, IQR 62–76) had a significantly higher RHR compared to HS (60 bpm, IQR 56–63). RHR was significantly higher at baseline in individuals who subsequently developed arthritis. Expression levels of α7nAChR were lower in AR subjects with RHR ≥ 70 bpm compared to those with RHR < 70 bpm, consistent with reduced activity of the parasympathetic cholinergic anti-inflammatory pathway. Interpretation These data support the notion that autonomic dysfunction precedes the development of RA. Individuals at risk of developing RA show autonomic dysfunction similar to established RA patients. Autonomic dysfunction is a predictor of development of arthritis in subjects at risk of RA, suggesting a role in its etiopathogenesis.
The autonomous nervous system is a neurological control system that acts largely unconsciously and regulates a variety of bodily functions. We found that dysfunction of this system may precede and predict the development of rheumatoid arthritis (RA), a chronic inflammatory disease with great unmet need. These findings provide important insights into the changes in the nervous system contributing to the development of this condition. They also open up the perspective of potential measures aimed at prevention of RA by restoring the balance in the nervous system before arthritis develops, which would have major implications for patients as well as society.
Collapse
|
Journal Article |
9 |
67 |
16
|
Oh Y, Zhang F, Wang Y, Lee EM, Choi IY, Lim H, Mirakhori F, Li R, Huang L, Xu T, Wu H, Li C, Qin CF, Wen Z, Wu QF, Tang H, Xu Z, Jin P, Song H, Ming GL, Lee G. Zika virus directly infects peripheral neurons and induces cell death. Nat Neurosci 2017; 20:1209-1212. [PMID: 28758997 PMCID: PMC5575960 DOI: 10.1038/nn.4612] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 07/01/2017] [Indexed: 12/16/2022]
Abstract
Zika virus (ZIKV)-infection is associated with neurological disorders of both the central and peripheral nervous systems (PNS), yet few studies have directly examined PNS-infection. Here we show that intraperitoneally or intraventricularly-injected ZIKV in the mouse could infect and impact peripheral neurons in vivo. Moreover, ZIKV productively infects stem cell-derived human neural crest cells and peripheral neurons in vitro, leading to increased cell death, transcriptional dysregulation and cell-type specific molecular pathology.
Collapse
|
Journal Article |
8 |
66 |
17
|
Abstract
Metabolite signals with short T(1) or T(2) are difficult to localize with full sensitivity. This limitation was overcome with the development and implementation of a single-shot, complete three-dimensional "non-echo" localization method with reduced sensitivity to spatial B(1) variation, which is suitable for measuring signals with very short T(1) or T(2), e.g., the (13)C NMR signals of glycogen. The proposed method is based on a T(1)-optimized outer volume suppression scheme using pulses of the hyperbolic secant type applied at different power levels, which is robust over a fivefold range of T(1). Strong lipid, muscle glycogen, and glucose signals originating outside the rat brain were suppressed. Signals of glycogen, aspartate, glutathione, GABA C4, N-acetyl aspartate as well as the C3 and C4 signals of glutamate and glutamine with resolved homonuclear (13)C-(13)C coupling were fully resolved in vivo at 9.4 Tesla using higher-order shimming. The method can be extended to other nuclei and to localized MRS of humans.
Collapse
|
|
25 |
60 |
18
|
Shin DH, Bae YC, Kim-Han JS, Lee JH, Choi IY, Son KH, Kang SS, Kim WK, Han BH. Polyphenol amentoflavone affords neuroprotection against neonatal hypoxic-ischemic brain damage via multiple mechanisms. J Neurochem 2006; 96:561-72. [PMID: 16336627 DOI: 10.1111/j.1471-4159.2005.03582.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Flavonoids are naturally occurring polyphenolic compounds that have many biological properties, including antioxidative, anti-inflammatory and neuroprotective effects. Here, we report that amentoflavone significantly reduced cell death induced by staurosporine, etoposide and sodium nitroprusside in neuroblastoma SH-SY5Y cells. In post-natal day 7 rats, hypoxic-ischemic (H-I) brain damage induced by unilateral carotid ligation and hypoxia resulted in distinct features of neuronal cell death including apoptosis and necrosis. In this model, a systemic administration of amentoflavone (30 mg/kg) markedly reduced the H-I-induced brain tissue loss with a wide therapeutic time window up to 6 h after the onset of hypoxia. Amentoflavone blocked the activation of caspase 3, characteristic of apoptosis, and the proteolytic cleavage of its substrates following H-I injury. Amentoflavone also reduced the excitotoxic/necrotic cell death after H-I injury in vivo and after oxygen/glucose deprivation in mouse mixed cultures in vitro. Treatment of mouse microglial cells with amentoflavone resulted in a significant decrease in the lipopolysaccharide-induced production of nitric oxide and induction of inducible nitric oxide synthase and cyclo-oxygenase-2. Furthermore, amentoflavone decreased the inflammatory activation of microglia after H-I injury when assessed by the microglial-specific marker OX-42. These data demonstrate for the first time that amentoflavone strongly protects the neonatal brain from H-I injury by blocking multiple cellular events leading to brain damage.
Collapse
|
|
19 |
59 |
19
|
Lee JH, Choi IY, Kil IS, Kim SY, Yang ES, Park JW. Protective role of superoxide dismutases against ionizing radiation in yeast. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1526:191-8. [PMID: 11325541 DOI: 10.1016/s0304-4165(01)00126-x] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The protective role of superoxide dismutases (SODs) against ionizing radiation, which generates reactive oxygen species (ROS) harmful to cellular function, was investigated in the wild-type and in mutant yeast strains lacking cytosolic CuZnSOD (sod1Delta), mitochondrial MnSOD (sod2Delta), or both SODs (sod1Deltasod2Delta). Upon exposure to ionizing radiation, there was a distinct difference between these strains in regard to viability and the level of protein carbonyl content, which is the indicative marker of oxidative damage to protein, intracellular H2O2 level, as well as lipid peroxidation. When the oxidation of 2',7'-dichlorofluorescin was used to examine the hydroperoxide production in yeast cells, the SOD mutants showed a higher degree of increase in fluorescence upon exposure to ionizing radiation as compared to wild-type cells. These results indicated that mutants deleted for SOD genes were more sensitive to ionizing radiation than isogenic wild-type cells. Induction and inactivation of other antioxidant enzymes, such as catalase, glucose 6-phosphate dehydrogenase, and glutathione reductase, were observed after their exposure to ionizing radiation both in wild-type and in mutant cells. However, wild-type cells maintained significantly higher activities of antioxidant enzymes than did mutant cells. These results suggest that both CuZnSOD and MnSOD may play a central role in protecting cells against ionizing radiation through the removal of ROS, as well as in the protection of antioxidant enzymes.
Collapse
|
Comparative Study |
24 |
51 |
20
|
Kim HS, Choi W, Baek EK, Kim YA, Yang SJ, Choi IY, Yoon KH, Cho JH. Efficacy of the smartphone-based glucose management application stratified by user satisfaction. Diabetes Metab J 2014; 38:204-10. [PMID: 25003074 PMCID: PMC4083027 DOI: 10.4093/dmj.2014.38.3.204] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 09/16/2013] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND We aimed to assess the efficacy of the smartphone-based health application for glucose control and patient satisfaction with the mobile network system used for glucose self-monitoring. METHODS Thirty-five patients were provided with a smartphone device, and self-measured blood glucose data were automatically transferred to the medical staff through the smartphone application over the course of 12 weeks. The smartphone user group was divided into two subgroups (more satisfied group vs. less satisfied group) based on the results of questionnaire surveys regarding satisfaction, comfort, convenience, and functionality, as well as their willingness to use the smartphone application in the future. The control group was set up via a review of electronic medical records by group matching in terms of age, sex, doctor in charge, and glycated hemoglobin (HbA1c). RESULTS Both the smartphone group and the control group showed a tendency towards a decrease in the HbA1c level after 3 months (7.7%±0.7% to 7.5%±0.7%, P=0.077). In the more satisfied group (n=27), the HbA1c level decreased from 7.7%±0.8% to 7.3%±0.6% (P=0.001), whereas in the less satisfied group (n=8), the HbA1c result increased from 7.7%±0.4% to 8.1%±0.5% (P=0.062), showing values much worse than that of the no-smartphone control group (from 7.7%±0.5% to 7.7%±0.7%, P=0.093). CONCLUSION In addition to medical feedback, device and network-related patient satisfaction play a crucial role in blood glucose management. Therefore, for the smartphone app-based blood glucose monitoring to be effective, it is essential to provide the patient with a well-functioning high quality tool capable of increasing patient satisfaction and willingness to use.
Collapse
|
research-article |
11 |
43 |
21
|
Wang X, Li B, Kim YJ, Wang YC, Li Z, Yu J, Zeng S, Ma X, Choi IY, Di Biase S, Smith DJ, Zhou Y, Li YR, Ma F, Huang J, Clarke N, To A, Gong L, Pham AT, Moon H, Pellegrini M, Yang L. Targeting monoamine oxidase A for T cell-based cancer immunotherapy. Sci Immunol 2021; 6:eabh2383. [PMID: 33990379 DOI: 10.1126/sciimmunol.abh2383] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Accepted: 04/15/2021] [Indexed: 12/11/2022]
Abstract
Monoamine oxidase A (MAO-A) is an enzyme best known for its function in the brain, where it breaks down neurotransmitters and thereby influences mood and behavior. Small-molecule MAO inhibitors (MAOIs) have been developed and are clinically used for treating depression and other neurological disorders. However, the involvement of MAO-A in antitumor immunity has not been reported. Here, we observed induction of the Maoa gene in tumor-infiltrating immune cells. Maoa knockout mice exhibited enhanced antitumor T cell immunity and suppressed tumor growth. MAOI treatment significantly suppressed tumor growth in preclinical mouse syngeneic and human xenograft tumor models in a T cell-dependent manner. Combining MAOI and anti-PD-1 treatments generated synergistic tumor suppression effects. Clinical data correlation studies associated intratumoral MAOA expression with T cell dysfunction and decreased patient survival in a broad range of cancers. We further demonstrated that MAO-A restrains antitumor T cell immunity through controlling intratumoral T cell autocrine serotonin signaling. Together, these data identify MAO-A as an immune checkpoint and support repurposing MAOI antidepressants for cancer immunotherapy.
Collapse
|
Research Support, N.I.H., Extramural |
4 |
38 |
22
|
Kim IJ, Lee KW, Park BY, Lee JK, Park J, Choi IY, Eom SJ, Chang TS, Kim MJ, Yeom YI, Chang SK, Lee YD, Choi EJ, Han PL. Molecular cloning of multiple splicing variants of JIP-1 preferentially expressed in brain. J Neurochem 1999; 72:1335-43. [PMID: 10098834 DOI: 10.1046/j.1471-4159.1999.721335.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) is activated by a variety of cellular or environmental stresses. Proper regulation of the SAPK/JNK pathway may be critical for cell survival or death under various conditions. In this study, we report the molecular cloning of novel isoforms of JIP-1, which harbor a putative phosphotyrosine interaction domain and a helix-loop-helix domain, as well as an SH3 homologous region in the C terminus. Northern analysis indicates that transcription variant jip-1 is expressed in brain and kidney and transcription variants jip-2 and jip-3 are specifically expressed in brain. In situ hybridization data showed that the hybridized jip messages were heavily concentrated in adult brain, and were particularly enriched in the cerebral cortex and hippocampus, the brain regions vulnerable to pathological states such as hypoxia-ischemia, epilepsy, and Alzheimer's disease. All the deduced protein products of the jip transcription variants appear to have a similar property in that they inhibit the SAPK/JNK stimulation when overexpressed. Inhibition of SAPK activation by overexpression of the novel isoform JIP-2a resulted in suppression of etoposide-induced cell death in a neuroglioma cell line, N18TG. These findings suggest that JIP may play an important role in regulation of the SAPK pathway that is involved in stress-induced cellular responses.
Collapse
|
|
26 |
38 |
23
|
Ko JH, Lee CS, Kim KH, Pang MG, Koo JS, Fang N, Koo DB, Oh KB, Youn WS, Zheng GD, Park JS, Kim SJ, Han YM, Choi IY, Lim J, Shin ST, Jin SW, Lee KK, Yoo OJ. Production of biologically active human granulocyte colony stimulating factor in the milk of transgenic goat. Transgenic Res 2000; 9:215-22. [PMID: 11032370 DOI: 10.1023/a:1008972010351] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We have developed a transgenic female goat harboring goat beta-casein promoter/human granulocyte colony stimulating factor (G-CSF) fusion gene by microinjection into fertilized one-cell goat zygotes. Human G-CSF was produced at levels of up to 50 microg/ml in transgenic goat milk. Its biological activity was equivalent to recombinant human G-CSF expressed from Chinese hamster ovary (CHO) cell when assayed using in vitro HL-60 cell proliferation. Human G-CSF from transgenic goat milk increased the total number of white blood cells in C57BL/6N mice with leucopenia induced by cyclophosphamide (CPA). The secreted human G-CSF was glycosylated although the degree of O-glycosylation was lower compared to CHO cell-derived human G-CSF.
Collapse
|
|
25 |
36 |
24
|
Piao HZ, Choi IY, Park JS, Kim HS, Cheong JH, Son KH, Jeon SJ, Ko KH, Kim WK. Wogonin inhibits microglial cell migration via suppression of nuclear factor-kappa B activity. Int Immunopharmacol 2008; 8:1658-62. [PMID: 18725324 DOI: 10.1016/j.intimp.2008.07.018] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2008] [Accepted: 07/29/2008] [Indexed: 01/06/2023]
Abstract
Previously, we and others have demonstrated that wogonin, an active component from the root of Scutellaria baicalensis Georgi, has a neuroprotective effect in cerebral ischemic insult. The neuroprotective effect of wogonin may at least in part be due to its anti-inflammatory properties. Microglial cells, well-known residential macrophages in the central nervous system, migrate to the ischemic lesion and play a pivotal role in the development of chronic inflammation. In the present study, we observed that wogonin potently inhibited microglial migration toward a chemokine, monocyte chemoattractant protein-1 (MCP-1). The anti-migratory effect of wogonin was provoked at nanomolar concentrations, at which wogonin did not significantly inhibit the production of cytokines and chemokines. NF-kappaB has previously shown to regulate microglial cell migration, and activation of cAMP-signaling pathway has also been associated with inhibition of microglial cell motility. In the present study, wogonin at low micromolar concentrations completely suppressed the activity of NF-kappaB in MCP-1-stimulated microglia, and NF-kappaB inhibitors such as N-acetyl cysteine and pyrrolidinedithiocarbamate inhibited the MCP-1-induced migration of microglial cells. However, wogonin did not stimulate the production of cAMP in microglial cells. Our results indicate that the anti-inflammatory activity of wogonin is exerted at least in part by suppressing microglial cell motility via inhibition of NF-kappaB activity.
Collapse
|
Research Support, Non-U.S. Gov't |
17 |
36 |
25
|
Choi W, Rho MJ, Park J, Kim KJ, Kwon YD, Choi IY. Information system success model for customer relationship management system in health promotion centers. Healthc Inform Res 2013; 19:110-20. [PMID: 23882416 PMCID: PMC3717434 DOI: 10.4258/hir.2013.19.2.110] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 06/20/2013] [Accepted: 06/24/2013] [Indexed: 11/23/2022] Open
Abstract
Objectives Intensified competitiveness in the healthcare industry has increased the number of healthcare centers and propelled the introduction of customer relationship management (CRM) systems to meet diverse customer demands. This study aimed to develop the information system success model of the CRM system by investigating previously proposed indicators within the model. Methods The evaluation areas of the CRM system includes three areas: the system characteristics area (system quality, information quality, and service quality), the user area (perceived usefulness and user satisfaction), and the performance area (personal performance and organizational performance). Detailed evaluation criteria of the three areas were developed, and its validity was verified by a survey administered to CRM system users in 13 nationwide health promotion centers. The survey data were analyzed by the structural equation modeling method, and the results confirmed that the model is feasible. Results Information quality and service quality showed a statistically significant relationship with perceived usefulness and user satisfaction. Consequently, the perceived usefulness and user satisfaction had significant influence on individual performance as well as an indirect influence on organizational performance. Conclusions This study extends the research area on information success from general information systems to CRM systems in health promotion centers applying a previous information success model. This lays a foundation for evaluating health promotion center systems and provides a useful guide for successful implementation of hospital CRM systems.
Collapse
|
Journal Article |
12 |
34 |