Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 25
Filter
1.
Korean J Gastroenterol ; 78(5): 295-299, 2021 11 25.
Article in English | MEDLINE | ID: mdl-34824188

ABSTRACT

A 54-year-old man was transferred from another hospital due to a hematoma in the third portion of the duodenum on abdomen CT. He had been admitted for 2 weeks due to vomiting at another hospital. He had abdominal discomfort and nausea without abdominal pain when he visited the Gwangyang Sarang Hospital. Other than a distended abdomen and mild general abdominal tenderness, the results of physical examination were unremarkable. Abdominal CT revealed an approximately 9 cm thick walled hematoma at the anteroinferior site of the duodenal third portion. Upper endoscopy revealed stenosis of the third portion of the duodenum without mucosal lesions. The endoscope was not advanced through the narrowed duodenal lumen. A retroperitoneal hematoma was diagnosed, and his state was classified as subacute rather than acute based on the duration. The surgeon did not recommend surgical treatment. Urgent treatment was unnecessary; he was managed conservatively. The size of the hematoma decreased from 9.0 cm to 5.8 cm on the following CT. He could begin to eat food on the 26th admission day, and he was discharged on the 31st admission day. The hematoma disappeared entirely on the following CT. This paper describes a rare case of idiopathic retroperitoneal hematoma with a spontaneous resolution.


Subject(s)
Gastrointestinal Hemorrhage , Hematoma , Abdominal Pain/etiology , Duodenum , Hematoma/diagnosis , Humans , Male , Middle Aged , Vomiting
2.
J Korean Med Sci ; 36(14): e90, 2021 Apr 12.
Article in English | MEDLINE | ID: mdl-33847081

ABSTRACT

BACKGROUND: Liver fibrosis is defined as the accumulation of the extracellular matrix and scar formation. The receptor for advanced glycation end products (RAGE) has been demonstrated to participate in fibrogenesis. S100B is a ligand of RAGE and exerts extracellular functions by inducing a series of signal transduction cascades. However, the involvement of S100B and RAGE in cholestasis-induced liver fibrosis remains unclear. In this study, we investigated S100B and RAGE expression during liver fibrosis in mice that underwent common bile duct ligation (BDL). METHODS: BDL was performed in 10-week-old male C57BL/6J mice with sham control (n = 26) and BDL (n = 26) groups. Expression levels of S100B, RAGE and fibrotic markers in the livers from both groups at week 1 and 3 after BDL were examined by western blot and quantitative real-time reverse transcription polymerase chain reaction analysis. Liver fibrotic changes were examined by histological and ultrastructural analysis. RESULTS: Histological staining with Sirius Red and the evaluation of the messenger RNA expression of fibrotic markers showed noticeable periportal fibrosis and bile duct proliferation. S100B was mainly present in bile duct epithelial cells, and its expression was upregulated in proportion to the ductular reaction during fibrogenesis by BDL. RAGE expression was also increased, and interestingly, triple immunofluorescence staining and transmission electron microscopy showed that both S100B and RAGE were expressed in proliferating bile duct epithelial cells and activated hepatic stellate cells (HSCs) of the BDL livers. In addition, in rat HSCs (HSC-T6), treatment with recombinant S100B protein significantly increased fibrotic markers in a dose-dependent manner, and RAGE small interfering RNA (siRNA) suppressed S100B-stimulated upregulation of fibrotic markers compared with cells treated with scramble siRNA and S100B. CONCLUSION: These findings suggest that the increased expression of S100B and RAGE and the interaction between S100B and RAGE may play an important role in ductular reaction and liver fibrosis induced by BDL.


Subject(s)
Liver Cirrhosis/pathology , Receptor for Advanced Glycation End Products/metabolism , S100 Calcium Binding Protein beta Subunit/metabolism , Animals , Bile Ducts/cytology , Bile Ducts/surgery , Cell Line , Disease Models, Animal , Epithelial Cells/cytology , Epithelial Cells/metabolism , Hepatic Stellate Cells/cytology , Hepatic Stellate Cells/metabolism , Liver/metabolism , Liver/pathology , Liver Cirrhosis/metabolism , Male , Mice , Mice, Inbred C57BL , RNA Interference , RNA, Messenger/metabolism , RNA, Small Interfering/metabolism , Rats , Receptor for Advanced Glycation End Products/antagonists & inhibitors , Receptor for Advanced Glycation End Products/genetics , Recombinant Proteins/biosynthesis , Recombinant Proteins/isolation & purification , Recombinant Proteins/pharmacology , S100 Calcium Binding Protein beta Subunit/genetics , S100 Calcium Binding Protein beta Subunit/pharmacology , Up-Regulation/drug effects
3.
J Neurosci ; 41(3): 446-460, 2021 01 20.
Article in English | MEDLINE | ID: mdl-33262248

ABSTRACT

Preconditioning peripheral nerve injury enhances the intrinsic growth capacity of DRGs sensory axons by inducing transcriptional upregulation of the regeneration-associated genes (RAGs). However, it is still unclear how preconditioning injury leads to the orchestrated induction of many RAGs. The present study identified Myc proto-oncogene as a transcriptional hub gene to regulate the expression of a distinct subset of RAGs in DRGs following the preconditioning injury. We demonstrated that c-MYC bound to the promoters of certain RAGs, such as Jun, Atf3, and Sprr1a, and that Myc upregulation following SNI preceded that of the RAGs bound by c-MYC. Marked DNA methylation of the Myc exon 3 sequences was implicated in the early transcriptional activation and accompanied by open histone marks. Myc deletion led to a decrease in the injury-induced expression of a distinct subset of RAGs, which were highly overlapped with the list of RAGs that were upregulated by Myc overexpression. Following dorsal hemisection spinal cord injury in female rats, Myc overexpression in DRGs significantly prevented the retraction of the sensory axons in a manner dependent on its downstream RAG, June Our results suggest that Myc plays a critical role in axon regeneration via its transcriptional activity to regulate the expression of a spectrum of downstream RAGs and subsequent effector molecules. Identification of more upstream hub transcription factors and the epigenetic mechanisms specific for individual hub transcription factors would advance our understanding of how the preconditioning injury induces orchestrated upregulation of RAGs.


Subject(s)
Gene Expression Regulation/genetics , Gene Expression Regulation/physiology , Nerve Regeneration/genetics , Nerve Regeneration/physiology , Peripheral Nerve Injuries/genetics , Peripheral Nerve Injuries/physiopathology , Proto-Oncogene Proteins c-myc/genetics , Proto-Oncogene Proteins c-myc/physiology , Animals , Axons/physiology , DNA Methylation , Epigenesis, Genetic/genetics , Female , Ganglia, Spinal/cytology , Ganglia, Spinal/physiology , Neurites , PC12 Cells , Rats , Rats, Sprague-Dawley , Sensory Receptor Cells/physiology
4.
Exp Neurol ; 326: 113177, 2020 04.
Article in English | MEDLINE | ID: mdl-31926166

ABSTRACT

Preconditioning peripheral nerve injury primes the sensory neurons in the dorsal root ganglia (DRGs) to acquire axon regeneration competence. Transcription of a large set of regeneration-associated-genes (RAGs) contributes to the enhanced intrinsic axonal regeneration capacity. However, the mechanism underlying the coordinated upregulation of RAGs orchestrated by preconditioning injury is unclear. We sought to determine potential influence of DNA methylation change on transcriptional activation of RAGs in the L4-L6 DRGs following sciatic nerve injury. Genome-wide sequencing revealed that about 20% of the methylated DNA fragments were differentially methylated, and >3000 genes contained differentially methylated regions. Not only demethylation but also increased methylation was observed to a similar extent. The change in the global DNA methylation did not correlate with the gene expression level of most genes, including the well-documented RAGs. However, pharmacological inhibition or activation of DNA methylation markedly attenuated the axon growth capacity of the preconditioned DRG neurons. Pharmacological perturbation of DNA methylation resulted in simultaneous downregulation of many highly overlapping non-transcription factor RAGs, which was accompanied by a concurrent, robust upregulation of SOCS3 and Serpine1. Overexpression of SOCS3 and Serpine1 in the DRG neurons overrode injury-induced axon growth competence, corroborating their roles as the negative regulators of axon regeneration. We conclude that the injury-induced global alteration of DNA methylome strongly influences the axon growth competence in preconditioned DRG neurons. Our results also suggest a possibility that perturbing DNA methylome changes might lead to the upregulation of negative regulator RAGs thereby attenuating axon growth capacity.


Subject(s)
Axons/pathology , DNA Methylation , Ischemic Preconditioning , Peripheral Nerve Injuries/pathology , Sensory Receptor Cells/pathology , Animals , Cells, Cultured , DNA Methylation/drug effects , Ganglia, Spinal/cytology , Ganglia, Spinal/pathology , Gene Expression Regulation/genetics , Male , Nerve Regeneration/genetics , Neurites/drug effects , Plasminogen Activator Inhibitor 1/biosynthesis , Plasminogen Activator Inhibitor 1/genetics , Rats , Rats, Sprague-Dawley , Suppressor of Cytokine Signaling 3 Protein/biosynthesis , Suppressor of Cytokine Signaling 3 Protein/genetics , Transcriptional Activation
5.
Mol Neurobiol ; 55(4): 3172-3184, 2018 Apr.
Article in English | MEDLINE | ID: mdl-28470584

ABSTRACT

Myelin basic protein (MBP) citrullination by peptidylarginine deiminase (PAD) enzymes leads to incomplete protein-lipid bilayer interactions and vulnerability to proteolytic enzymes, resulting in disorganization of the myelin sheath in the central nervous system. Therefore, citrullinated MBP (citMBP) has been suggested as a hallmark of demyelination, but how citMBP is implicated in prion diseases remains unknown. For the first time, we developed mouse monoclonal anti-citMBP IgG1 (clones 1B8, 1H1, and 3C6) and IgM (clone 3G5) antibodies that recognize human citMBP at its R25, R122, and R130 residues and at its C-terminal region (or the corresponding sites in mouse MBP), respectively. Using a biochemical, immunohistochemical, and immunogold-silver staining for electron microscopy techniques, we found that MBP residue R23 (corresponding to human R25) was specifically citrullinated, was stained as intense punctae in the corpus callosum, the striatum, and the cerebellar white matter, and was predominantly localized in disorganized myelin in the brains of scrapie-infected mice. In the brains of Creutzfeldt-Jakob disease (CJD) patients, MBP residues R25, R122, and R130 were markedly citrullinated and were stained as fibrils and punctae. In particular, white matter regions, such as the midbrain and the medulla, exhibited high levels of citMBP compared to other regions. However, the high levels of citMBP were not correlated with PAD2 expression. The clone 3G5 recognized significantly increased expression of the 18.5 kDa and/or 21.5 kDa variants of MBP in prion disease. Our findings suggest that significantly increased levels of citMBP may reflect demyelinating neuropathology, and that these newly developed antibodies may be useful for identifying demyelination.


Subject(s)
Antibodies, Monoclonal/immunology , Central Nervous System/pathology , Citrullination , Demyelinating Diseases/metabolism , Myelin Basic Protein/metabolism , Prion Diseases/immunology , Aged , Aged, 80 and over , Animals , Brain/metabolism , Brain/pathology , Brain/ultrastructure , Creutzfeldt-Jakob Syndrome/metabolism , Creutzfeldt-Jakob Syndrome/pathology , Female , Humans , Male , Mice , Middle Aged , Myelin Sheath/metabolism , Myelin Sheath/pathology , Scrapie/immunology , Scrapie/pathology , White Matter/metabolism , White Matter/pathology
6.
Exp Neurobiol ; 27(6): 489-507, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30636901

ABSTRACT

Survival and migration of transplanted neural stem cells (NSCs) are prerequisites for therapeutic benefits in spinal cord injury. We have shown that survival of NSC grafts declines after transplantation into the injured spinal cord, and that combining treadmill training (TMT) enhances NSC survival via insulin-like growth factor-1 (IGF-1). Here, we aimed to obtain genetic evidence that IGF-1 signaling in the transplanted NSCs determines the beneficial effects of TMT. We transplanted NSCs heterozygous (+/-) for Igf1r, the gene encoding IGF-1 receptor, into the mouse spinal cord after injury, with or without combining TMT. We analyzed the influence of genotype and TMT on locomotor recovery and survival and migration of NSC grafts. In vitro experiments were performed to examine the potential roles of IGF-1 signaling in the migratory ability of NSCs. Mice receiving +/- NSC grafts showed impaired locomotor recovery compared with those receiving wild-type (+/+) NSCs. Locomotor improvement by TMT was more pronounced with +/+ grafts. Deficiency of one allele of Igf1r significantly reduced survival and migration of the transplanted NSCs. Although TMT did not significantly influence NSC survival, it substantially enhanced the extent of migration for only +/+ NSCs. Cultured neurospheres exhibited dynamic motility with cytoplasmic protrusions, which was regulated by IGF-1 signaling. IGF-1 signaling in transplanted NSCs may be essential in regulating their survival and migration. Furthermore, TMT may promote NSC graft-mediated locomotor recovery via activation of IGF-1 signaling in transplanted NSCs. Dynamic NSC motility via IGF-1 signaling may be the cellular basis for the TMT-induced enhancement of migration.

7.
PLoS One ; 11(12): e0167293, 2016.
Article in English | MEDLINE | ID: mdl-27936017

ABSTRACT

Prion diseases are infectious and fatal neurodegenerative diseases which require the cellular prion protein, PrPC, for development of diseases. The current study shows that the PrPC augments infectivity and plaque formation of a mouse endogenous retrovirus, MuLV. We have established four neuronal cell lines expressing mouse PrPC, PrP+/+; two express wild type PrPC (MoPrPwild) and the other two express mutant PrPC (MoPrPmut). Infection of neuronal cells from various PrP+/+ and PrP-/- (MoPrPKO) lines with MuLV yielded at least three times as many plaques in PrP+/+ than in PrP-/-. Furthermore, among the four PrP+/+ lines, one mutant line, P101L, had at least 2.5 times as many plaques as the other three PrP+/+ lines. Plaques in P101L were four times larger than those in other PrP+/+ lines. Colocalization of PrP and CAgag was seen in MuLV-infected PrP+/+ cells. In the PrP-MuLV interaction, the involvement of galectin-3 and -6 was observed by immunoprecipitation with antibody to PrPC. These results suggest that PrPC combined with galectin-3 and -6 can act as a receptor for MuLV. P101L, the disease form of mutant PrPC results suggest the genetic mutant form of PrPC may be more susceptible to viral infection.


Subject(s)
Galectin 3/metabolism , Galectins/metabolism , Leukemia Virus, Murine/growth & development , Neurons/metabolism , PrPC Proteins/metabolism , Animals , Animals, Newborn , Astrocytes/cytology , Astrocytes/metabolism , Astrocytes/virology , Blotting, Western , Cell Line , Cells, Cultured , Endogenous Retroviruses/growth & development , Endogenous Retroviruses/physiology , Galectin 3/genetics , Galectins/genetics , Hippocampus/cytology , Hippocampus/virology , Host-Pathogen Interactions , Leukemia Virus, Murine/physiology , Mice, Knockout , Microscopy, Confocal , Neurons/cytology , Neurons/virology , PrPC Proteins/genetics , Protein Binding , Reverse Transcriptase Polymerase Chain Reaction
8.
Mol Neurobiol ; 53(5): 3102-3112, 2016 07.
Article in English | MEDLINE | ID: mdl-25983034

ABSTRACT

The most prominent hallmark of prion diseases is prion protein conversion and the subsequent deposition of the altered prions, PrP(Sc), at the pathological sites of affected individuals, particularly in the brain. A previous study has demonstrated that the N-terminus of the pathogenic prion isoform (PrP(Sc)) is modified with advanced glycation end products (AGEs), most likely at one or more of the three Lys residues (positions 23, 24, and 27) in the N-terminus (23KKRPKP28). The current study investigated whether N(ε)-(carboxymethyl)lysine (CML), a major AGE form specific to Lys residues produced by nonenzymatic glycation, is an AGE adduct of the N-terminus of PrP(Sc). We show that CML is linked to at least one Lys residue at the N-terminus of PrP(Sc) in 263K prion-infected hamster brains and at least one of the eight Lys residues (positions 101, 104, 106, 110, 185, 194, 204, and 220) in the proteinase K (PK)-resistant core region of PrP(Sc). The nonenzymatic glycation of the Lys residue(s) of PrP(Sc) with CML likely occurs in the widespread prion-deposit areas within infected brains, particularly in some of the numerous tyrosine hydroxylase-positive thalamic and hypothalamic nuclei. CML glycation does not occur in PrP(C) but is seen in the pathologic PrP(Sc) isoform. Furthermore, the modification of PrP(Sc) with CML may be closely involved in prion propagation and deposition in pathological brain areas.


Subject(s)
Lysine/analogs & derivatives , PrPSc Proteins/metabolism , Animals , Cell Compartmentation , Cell Membrane/metabolism , Endopeptidase K/metabolism , Glycation End Products, Advanced/metabolism , Glycosylation , Lysine/metabolism , Male , Mesocricetus , Neurons/metabolism , PrPSc Proteins/chemistry , Protein Isoforms/metabolism , Solubility , Thalamus/metabolism , Thalamus/pathology , Tyrosine 3-Monooxygenase/metabolism
10.
J Neurosci ; 35(48): 15934-47, 2015 Dec 02.
Article in English | MEDLINE | ID: mdl-26631474

ABSTRACT

CNS neurons in adult mammals do not spontaneously regenerate axons after spinal cord injury. Preconditioning peripheral nerve injury allows the dorsal root ganglia (DRG) sensory axons to regenerate beyond the injury site by promoting expression of regeneration-associated genes. We have previously shown that peripheral nerve injury increases the number of macrophages in the DRGs and that the activated macrophages are critical to the enhancement of intrinsic regeneration capacity. The present study identifies a novel chemokine signal mediated by CCL2 that links regenerating neurons with proregenerative macrophage activation. Neutralization of CCL2 abolished the neurite outgrowth activity of conditioned medium obtained from neuron-macrophage cocultures treated with cAMP. The neuron-macrophage interactions that produced outgrowth-promoting conditioned medium required CCL2 in neurons and CCR2/CCR4 in macrophages. The conditioning effects were abolished in CCL2-deficient mice at 3 and 7 d after sciatic nerve injury, but CCL2 was dispensable for the initial growth response and upregulation of GAP-43 at the 1 d time point. Intraganglionic injection of CCL2 mimicked conditioning injury by mobilizing M2-like macrophages. Finally, overexpression of CCL2 in DRGs promoted sensory axon regeneration in a rat spinal cord injury model without harmful side effects. Our data suggest that CCL2-mediated neuron-macrophage interaction plays a critical role for amplification and maintenance of enhanced regenerative capacity by preconditioning peripheral nerve injury. Manipulation of chemokine signaling mediating neuron-macrophage interactions may represent a novel therapeutic approach to promote axon regeneration after CNS injury.


Subject(s)
Chemokine CCL2/metabolism , Macrophages/physiology , Nerve Regeneration/genetics , Neurons/physiology , Peripheral Nerve Injuries/physiopathology , Animals , Cells, Cultured , Chemokine CCL2/genetics , Cholera Toxin/metabolism , Coculture Techniques , Dependovirus/genetics , Disease Models, Animal , Female , Ganglia, Spinal/cytology , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Mice , Mice, Inbred C57BL , Mice, Transgenic , Nerve Regeneration/physiology , Nerve Tissue Proteins/metabolism , Neurites/physiology , Neurons/cytology , Pain Measurement , Pain Threshold/physiology , Rats , Rats, Sprague-Dawley , Receptors, CCR2/genetics , Receptors, CCR2/metabolism
11.
Nanoscale ; 6(24): 14622-6, 2014 Dec 21.
Article in English | MEDLINE | ID: mdl-25355156

ABSTRACT

We observed giant enhancement of the Raman intensity from 4-Mpy molecules adsorbed on semiconducting one-dimensional ZnO nanostructures, nanowires and nanocones, without involving any noble metals. Interestingly, the enhancement is strongly dependent on the geometry of ZnO nanostructures and can mainly be explained by the cavity-like structural resonance of the electric field. Our results can be applied to systematically create hot spots for Raman signal enhancement using one-dimensional semiconducting nanomaterials.

12.
J Neurosci ; 34(38): 12788-800, 2014 Sep 17.
Article in English | MEDLINE | ID: mdl-25232115

ABSTRACT

Combining cell transplantation with activity-based rehabilitation is a promising therapeutic approach for spinal cord repair. The present study was designed to investigate potential interactions between the transplantation (TP) of neural stem cells (NSCs) obtained at embryonic day 14 and treadmill training (TMT) in promoting locomotor recovery and structural repair in rat contusive injury model. Combination of TMT with NSC TP at 1 week after injury synergistically improved locomotor function. We report here that combining TMT increased the survival of grafted NSCs by >3-fold and >5-fold at 3 and 9 weeks after injury, respectively. The number of surviving NSCs was significantly correlated with the extent of locomotor recovery. NSCs grafted into the injured spinal cord were under cellular stresses induced by reactive nitrogen or oxygen species, which were markedly attenuated by TMT. TMT increased the concentration of insulin-like growth factor-1 (IGF-1) in the CSF. Intrathecal infusion of neutralizing IGF-1 antibodies, but not antibodies against either BDNF or Neurotrophin-3 (NT-3), abolished the enhanced survival of NSC grafts by TMT. The combination of TP and TMT also resulted in tissue sparing, increased myelination, and restoration of serotonergic fiber innervation to the lumbar spinal cord to a larger extent than that induced by either TP or TMT alone. Therefore, we have discovered unanticipated beneficial effects of TMT in modulating the survival of grafted NSCs via IGF-1. Our study identifies a novel neurobiological basis for complementing NSC-based spinal cord repair with activity-based neurorehabilitative approaches.


Subject(s)
Insulin-Like Growth Factor I/physiology , Motor Activity/physiology , Neural Stem Cells/physiology , Neural Stem Cells/transplantation , Signal Transduction , Spinal Cord Injuries/rehabilitation , Spinal Cord Injuries/therapy , Animals , Antibodies, Neutralizing/administration & dosage , Antibodies, Neutralizing/immunology , Antibodies, Neutralizing/pharmacology , Brain-Derived Neurotrophic Factor/immunology , Cell Survival/immunology , Cell Survival/physiology , Combined Modality Therapy/methods , Female , Injections, Spinal , Insulin-Like Growth Factor I/immunology , Insulin-Like Growth Factor I/metabolism , Lumbosacral Region/innervation , Myelin Sheath/metabolism , Neurotrophin 3/immunology , Rats , Reactive Nitrogen Species/metabolism , Reactive Oxygen Species/metabolism , Recovery of Function/physiology , Serotonergic Neurons/physiology , Spinal Cord Injuries/metabolism , Spinal Cord Injuries/physiopathology , Spinal Cord Regeneration/immunology , Spinal Cord Regeneration/physiology
13.
Anticancer Res ; 34(9): 4857-68, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25202067

ABSTRACT

BACKGROUND/AIM: The aim of the present study was to elucidate whether tunicamycin (TM) induces paraptosis as a cell death subroutine in anaplastic thyroid carcinoma (ATC) cells. MATERIALS AND METHODS: 8505C, CAL62 and FRO cells were used. After treatment of TM, cell survival and morphology were investigated. The effect of the BRAF(V600E) inhibitor PLX4032 in combination with TM was evaluated. RESULTS: In FRO cells, TM induced paraptosis characteristic of cytoplasmic vacuolation and endoplasmic reticulum (ER) swelling, which was not associated with caspase activation and ER stress. TM-induced paraptosis was ameliorated by pre-treatment with the translation inhibitor cycloheximide, while it was accelerated by pre-treatment with the proteasome inhibitor MG132. PLX4032 augmented TM-induced paraptosis. CONCLUSION: TM induces paraptosis relevant to de novo protein synthesis and proteasomal activity, and inhibition of BRAF(V600E) potentiates TM-induced paraptosis in FRO cells harboring BRAF(V600E).


Subject(s)
Apoptosis/drug effects , Proto-Oncogene Proteins B-raf/antagonists & inhibitors , Thyroid Neoplasms/metabolism , Tunicamycin/pharmacology , Caspases/metabolism , Cell Line, Tumor , Cell Survival/drug effects , Endoplasmic Reticulum Stress , Enzyme Activation/drug effects , Humans , Indoles/pharmacology , Mutation , Proteasome Endopeptidase Complex/metabolism , Protein Biosynthesis , Proto-Oncogene Proteins B-raf/genetics , Proto-Oncogene Proteins B-raf/metabolism , Sulfonamides/pharmacology , Thyroid Carcinoma, Anaplastic , Thyroid Neoplasms/genetics , Thyroid Neoplasms/pathology , Vemurafenib
14.
Front Aging Neurosci ; 6: 207, 2014.
Article in English | MEDLINE | ID: mdl-25202268

ABSTRACT

Normal cellular prion protein (PrP(C)) is highly expressed in the central nervous system. The Zürich I Prnp-deficient mouse strain did not show an abnormal phenotype in initial studies, however, in later studies, deficits in exploratory behavior and short- and long-term memory have been revealed. In the present study, numerous autophagic vacuoles were found in neurons from Zürich I Prnp-deficient mice. The autophagic accumulation in the soma of cortical neurons in Zürich I Prnp-deficient mice was observed as early as 3 months of age, and in the hippocampal neurons at 6 months of age. Specifically, there is accumulation of electron dense pigments associated with autophagy in the neurons of Zürich I Prnp-deficient mice. Furthermore, autophagic accumulations were observed as early as 3 months of age in the CA3 region of hippocampal and cerebral cortical neuropils. The autophagic vacuoles increased with age in the hippocampus of Zürich I Prnp-deficient mice at a faster rate and to a greater extent than in normal C57BL/6J mice, whereas the cortex exhibited high levels that were maintained from 3 months old in Zürich I Prnp-deficient mice. The pigmented autophagic accumulation is due to the incompletely digested material from autophagic vacuoles. Furthermore, a deficiency in PrP(C) may disrupt the autophagic flux by inhibiting autophagosome-lysosomal fusion. Overall, our results provide insight into the protective role of PrP(C) in neurons, which may play a role in normal behavior and other brain functions.

15.
J Virol ; 88(21): 12311-25, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25122791

ABSTRACT

UNLABELLED: The hepatitis C virus (HCV) life cycle is tightly regulated by lipid metabolism of host cells. In order to identify host factors involved in HCV propagation, we have recently screened a small interfering RNA (siRNA) library targeting host genes that control lipid metabolism and lipid droplet formation using cell culture-grown HCV (HCVcc)-infected cells. We selected and characterized the gene encoding stearoyl coenzyme A (CoA) desaturase 1 (SCD1). siRNA-mediated knockdown or pharmacological inhibition of SCD1 abrogated HCV replication in both subgenomic replicon and Jc1-infected cells, while exogenous supplementation of either oleate or palmitoleate, products of SCD1 activity, resurrected HCV replication in SCD1 knockdown cells. SCD1 was coimmunoprecipitated with HCV nonstructural proteins and colocalized with both double-stranded RNA (dsRNA) and HCV nonstructural proteins, indicating that SCD1 is associated with HCV replication complex. Moreover, SCD1 was fractionated and enriched with HCV nonstructural proteins at detergent-resistant membrane. Electron microscopy data showed that SCD1 is required for NS4B-mediated intracellular membrane rearrangement. These data further support the idea that SCD1 is associated with HCV replication complex and that its products may contribute to the proper formation and maintenance of membranous web structures in HCV replication complex. Collectively, these data suggest that manipulation of SCD1 activity may represent a novel host-targeted antiviral strategy for the treatment of HCV infection. IMPORTANCE: Stearoyl coenzyme A (CoA) desaturase 1 (SCD1), a liver-specific enzyme, regulates hepatitis C virus (HCV) replication through its enzyme activity. HCV nonstructural proteins are associated with SCD1 at detergent-resistant membranes, and SCD1 is enriched on the lipid raft by HCV infection. Therein, SCD1 supports NS4B-mediated membrane rearrangement to provide a suitable microenvironment for HCV replication. We demonstrated that either genetic or chemical knockdown of SCD1 abrogated HCV replication in both replicon cells and HCV-infected cells. These findings provide novel mechanistic insights into the roles of SCD1 in HCV replication.


Subject(s)
Hepacivirus/physiology , Host-Pathogen Interactions , Stearoyl-CoA Desaturase/metabolism , Virus Replication , Cell Line , Cell Membrane/ultrastructure , Gene Knockdown Techniques , Genetic Testing , Hepatocytes/virology , Humans , Microscopy, Electron
16.
Biochem Biophys Res Commun ; 448(2): 157-62, 2014 May 30.
Article in English | MEDLINE | ID: mdl-24755077

ABSTRACT

Mitochondrial dysfunction is a common and prominent feature of many neurodegenerative diseases, including prion diseases; it is induced by oxidative stress in scrapie-infected animal models. In previous studies, we found swelling and dysfunction of mitochondria in the brains of scrapie-infected mice compared to brains of controls, but the mechanisms underlying mitochondrial dysfunction remain unclear. To examine whether the dysregulation of mitochondrial proteins is related to the mitochondrial dysfunction associated with prion disease, we investigated the expression patterns of mitochondrial fusion and fission proteins in the brains of ME7 prion-infected mice. Immunoblot analysis revealed that Mfn1 was up-regulated in both whole brain and specific brain regions, including the cerebral cortex and hippocampus, of ME7-infected mice compared to controls. Additionally, expression levels of Fis1 and Mfn2 were elevated in the hippocampus and the striatum, respectively, of the ME7-infected brain. In contrast, Dlp1 expression was significantly reduced in the hippocampus in the ME7-infected brain, particularly in the cytosolic fraction. Finally, we observed abnormal mitochondrial enlargement and histopathological change in the hippocampus of the ME7-infected brain. These observations suggest that the mitochondrial dysfunction, which is presumably caused by the dysregulation of mitochondrial fusion and fission proteins, may contribute to the neuropathological changes associated with prion disease.


Subject(s)
Brain/pathology , Mitochondria/pathology , Mitochondrial Dynamics , Scrapie/pathology , Animals , Brain/metabolism , Cytosol/metabolism , Disease Models, Animal , Dynamins/metabolism , GTP Phosphohydrolases , Hippocampus/metabolism , Hippocampus/pathology , Mice , Mice, Inbred C57BL , Mitochondria/metabolism , Mitochondrial Proteins/metabolism , PrPSc Proteins/metabolism , Scrapie/metabolism
17.
J Glaucoma ; 23(4): 225-31, 2014.
Article in English | MEDLINE | ID: mdl-24682006

ABSTRACT

BACKGROUND: To compare the macular and peripapillary choroidal thickness between normal and glaucoma eyes and find out factors related to choroidal thickness using enhanced depth imaging (EDI) of Heidelberg Spectralis SD-OCT. STUDY DESIGN: Cross-sectional transverse study. METHODS: A total of 108 glaucoma patients and 48 healthy controls were included in the analysis. Choroidal thickness was measured from 6 mm length radial B-scans at the macular and the optic nerve head by EDI OCT. Choroidal thickness was compared between normal controls, normal tension glaucoma (NTG) patients, and primary open-angle glaucoma (POAG) patients. Factors related to choroidal thickness were analyzed by regression analysis. RESULTS: There were no differences in average, temporal, nasal, superior, and inferior macular choroidal thickness between normal, NTG, and POAG eyes. The peripapillary thickness did not differ between normal and POAG eyes; however, average, temporal, nasal, superior, and inferior peripapillary choroidal thickness were significantly thinner in NTG eyes. Axial length (ß=-11.36, P<0.001) was the most significant factor associated with peripapillary choroidal thickness, followed by age (ß=-5.10, P<0.001). Glaucoma type (ß=-11.28, P<0.001) were also significantly associated with peripapillary choroidal thickness. CONCLUSIONS: Peripapillary choroidal thickness was significantly reduced in NTG eyes based on EDI OCT measurements in vivo.


Subject(s)
Choroid/pathology , Glaucoma, Open-Angle/complications , Low Tension Glaucoma/complications , Tomography, Optical Coherence , Cross-Sectional Studies , Female , Glaucoma, Open-Angle/diagnosis , Gonioscopy , Healthy Volunteers , Humans , Intraocular Pressure/physiology , Low Tension Glaucoma/diagnosis , Macula Lutea , Male , Middle Aged , Optic Disk , Organ Size , Tonometry, Ocular , Visual Acuity/physiology , Visual Field Tests , Visual Fields/physiology
18.
PLoS One ; 9(2): e88215, 2014.
Article in English | MEDLINE | ID: mdl-24520355

ABSTRACT

Traumatic spinal cord injury (SCI) often leads to debilitating loss of locomotor function. Neuroplasticity of spinal circuitry underlies some functional recovery and therefore represents a therapeutic target to improve locomotor function following SCI. However, the cellular and molecular mechanisms mediating neuroplasticity below the lesion level are not fully understood. The present study performed a gene expression profiling in the rat lumbar spinal cord at 1 and 3 weeks after contusive SCI at T9. Another group of rats received treadmill locomotor training (TMT) until 3 weeks, and gene expression profiles were compared between animals with and without TMT. Microarray analysis showed that many inflammation-related genes were robustly upregulated in the lumbar spinal cord at both 1 and 3 weeks after thoracic injury. Notably, several components involved in an early complement activation pathway were concurrently upregulated. In line with the microarray finding, the number of microglia substantially increased not only in the white matter but also in the gray matter. C3 and complement receptor 3 were intensely expressed in the ventral horn after injury. Furthermore, synaptic puncta near ventral motor neurons were frequently colocalized with microglia after injury, implicating complement activation and microglial cells in synaptic remodeling in the lumbar locomotor circuitry after SCI. Interestingly, TMT did not influence the injury-induced upregulation of inflammation-related genes. Instead, TMT restored pre-injury expression patterns of several genes that were downregulated by injury. Notably, TMT increased the expression of genes involved in neuroplasticity (Arc, Nrcam) and angiogenesis (Adam8, Tie1), suggesting that TMT may improve locomotor function in part by promoting neurovascular remodeling in the lumbar motor circuitry.


Subject(s)
Lumbar Vertebrae/pathology , Motor Activity/genetics , Physical Conditioning, Animal , Spinal Cord Injuries/genetics , Spinal Cord Injuries/physiopathology , Spinal Cord/pathology , Thoracic Injuries/genetics , Animals , Down-Regulation/genetics , Female , Gene Expression Profiling , Inflammation/genetics , Inflammation/pathology , Lumbar Vertebrae/physiopathology , Microglia/metabolism , Microglia/pathology , Oligonucleotide Array Sequence Analysis , Protein Interaction Maps/genetics , Rats , Rats, Sprague-Dawley , Recovery of Function/genetics , Reproducibility of Results , Spinal Cord/physiopathology , Spinal Cord Injuries/pathology , Thoracic Injuries/pathology , Thoracic Injuries/physiopathology , Up-Regulation/genetics
19.
Nanoscale ; 5(24): 12261-71, 2013 Dec 21.
Article in English | MEDLINE | ID: mdl-24150526

ABSTRACT

Nanopatterned 2-dimensional Au nanocluster arrays with controlled configuration are fabricated onto reconstructed nanoporous poly(styrene-block-vinylpyridine) inverse micelle monolayer films. Near-field coupling of localized surface plasmons is studied and compared for disordered and ordered core-centered Au NC arrays. Differences in evolution of the absorption band and field enhancement upon Au nanoparticle adsorption are shown. The experimental results are found to be in good agreement with theoretical studies based on the finite-difference time-domain method and rigorous coupled-wave analysis. The realized Au nanopatterns are exploited as substrates for surface-enhanced Raman scattering and integrated into Kretschmann-type SPR sensors, based on which unprecedented SPR-coupling-type sensors are demonstrated.


Subject(s)
Biosensing Techniques/instrumentation , Gold/chemistry , Micelles , Nanostructures/chemistry , Surface Plasmon Resonance/instrumentation , Biotin/chemistry , Metal Nanoparticles/chemistry , Spectrum Analysis, Raman/instrumentation , Stereoisomerism , Streptavidin/chemistry , Sulfhydryl Compounds/chemistry , Surface Properties
20.
Pathogens ; 2(3): 436-45, 2013 Jun 26.
Article in English | MEDLINE | ID: mdl-25437200

ABSTRACT

Cellular prion protein (PrPC) plays an important role in the cellular defense against oxidative stress. However, the exact protective mechanism of PrPC is unclear. Autophagy is essential for survival, differentiation, development, and homeostasis in several organisms. Although the role that autophagy plays in neurodegenerative disease has yet to be established, it is clear that autophagy-induced cell death is observed in neurodegenerative disorders that exhibit protein aggregations. Moreover, autophagy can promote cell survival and cell death under various conditions. In this review, we describe the involvement of autophagy in prion disease and the effects of PrPC.

SELECTION OF CITATIONS
SEARCH DETAIL
...