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1.
J Orthop Sci ; 29(2): 585-588, 2024 Mar.
Article En | MEDLINE | ID: mdl-36822946

INTRODUCTION: This study aimed to investigate the survival rate, postoperative complications, and walking ability in cemented hemiarthroplasty (HA) for displaced femoral neck fractures according to the anaesthesia method. METHODS: We conducted a retrospective study of a multicentre group (the TRON group). Three hundred fifty-eight patients who underwent cemented HA between 2015 and 2019 were selected; 289 patients of ≥75 years of age with no missing data were included. Patient background factors were matched and patients were assigned to spinal anaesthesia (SA) and general anaesthesia (GA) groups. The primary outcome was death at any time during the follow-up period. Secondary outcomes included postoperative complications and walking ability assessed using the Parker mobility score (PMS). Overall survival was evaluated using the Kaplan-Meier method, and differences were compared using the log-rank test. The incidence of each complication and PMS were compared between the two groups using Fisher's exact test. RESULTS: Overall survival during follow-up was significantly higher in the SA group in comparison to the GA group (p = 0.037). In the SA and GA groups, the survival rate at 3 months postoperatively was 98.4% and 95.5%, respectively. The incidence of postoperative pneumonia was significantly higher in the GA (p = 0.012), and PMS at 3 months postoperatively was significantly higher in the SA group (p = 0.016). CONCLUSION: The survival rate of elderly patients who underwent cemented HA was better in the SA group. General anaesthesia in cemented HA may be associated with lower life expectancy, increased incidence of pneumonia, and decreased walking ability.


Anesthesia , Arthroplasty, Replacement, Hip , Femoral Neck Fractures , Hemiarthroplasty , Pneumonia , Humans , Aged , Retrospective Studies , Hemiarthroplasty/methods , Femoral Neck Fractures/surgery , Postoperative Complications/etiology , Anesthesia/adverse effects , Pneumonia/complications , Pneumonia/surgery , Treatment Outcome , Bone Cements , Arthroplasty, Replacement, Hip/adverse effects
2.
Article En | MEDLINE | ID: mdl-25818247

Numerous preclinical studies demonstrate that changes in gene expression in the brain occur in animal models of depression using exposure to stress, such as social defeat and leaned helplessness, and that repeated administration of antidepressants ameliorates these stress-induced changes in gene expression. These findings suggest that alteration in gene transcription in the central nervous system in response to stress plays an important role in the pathophysiology of depression. Recent advances in epigenetics have led to the realization that chromatin remodeling mediated by histone deacetylase (HDAC) is closely involved in the regulation of gene transcription. In this context, we first review several preclinical studies demonstrating the antidepressant-like efficacy of HDAC inhibitors. We then suggest the efficacy of HDAC inhibitors in treatment-resistant depression based on the mechanism of action of HDAC. Finally, we discuss the possibility of using HDAC inhibitors in patients with treatment-resistant depression.


Antidepressive Agents/therapeutic use , Depressive Disorder/drug therapy , Histone Deacetylase Inhibitors/therapeutic use , Animals , Antidepressive Agents/pharmacology , Depressive Disorder/genetics , Depressive Disorder/metabolism , Gene Expression Regulation/drug effects , Histone Deacetylase Inhibitors/pharmacology , Humans
3.
Psychopharmacology (Berl) ; 229(1): 51-62, 2013 Sep.
Article En | MEDLINE | ID: mdl-23584669

RATIONALE: Given that impairment of fear extinction plays a pivotal role in the pathophysiology of posttraumatic stress disorder (PTSD), drugs that facilitate fear extinction may be useful as novel treatments for PTSD. Histone deacetylase (HDAC) inhibitors have recently been shown to enhance fear extinction in animal studies. OBJECTIVES: Using a single prolonged stress (SPS) paradigm, an animal model of PTSD, we examined whether the HDAC inhibitor vorinostat can facilitate fear extinction in rats, and elucidated the mechanism by which vorinostat enhanced fear extinction, focusing on the N-methyl-D-aspartate (NMDA) receptor signals in the hippocampus. METHODS: Seven days after SPS, rats received contextual fear conditioning, followed by 2-day extinction training. Vorinostat was intraperitoneally injected immediately after second extinction training session. Contextual fear response was assessed 24 h after vorinostat injection. Hippocampal tissues were dissected 2 h after vorinostat injection. The levels of mRNA and protein tested were measured by RT-PCR or western blotting, respectively. RESULTS: Systemic administration of vorinostat with extinction training significantly enhanced fear extinction in SPS rats as compared with the controls. Furthermore, vorinostat enhanced the hippocampal levels of NR2B and calcium/calmodulin kinase II (CaMKII) α and ß proteins, accompanied by increases in the levels of acetylated histone H3 and H4. CONCLUSIONS: These findings suggest that vorinostat ameliorated the impaired fear extinction in SPS rats, and this effect was associated with an increase in histone acetylation and thereby enhancement of NR2B and CaMKII in the hippocampus. Our results may provide new insight into the molecular and therapeutic mechanisms of PTSD.


Calcium-Calmodulin-Dependent Protein Kinase Type 2/biosynthesis , Extinction, Psychological/drug effects , Fear/drug effects , Hydroxamic Acids/therapeutic use , Receptors, N-Methyl-D-Aspartate/biosynthesis , Stress Disorders, Post-Traumatic/drug therapy , Animals , Disease Models, Animal , Extinction, Psychological/physiology , Fear/physiology , Hippocampus/drug effects , Hippocampus/metabolism , Histone Deacetylase Inhibitors/pharmacology , Histone Deacetylase Inhibitors/therapeutic use , Hydroxamic Acids/pharmacology , Male , Rats , Rats, Sprague-Dawley , Vorinostat
4.
Nihon Shinkei Seishin Yakurigaku Zasshi ; 32(4): 195-201, 2012 Aug.
Article Ja | MEDLINE | ID: mdl-23012887

Pharmacological agents enhancing fear extinction may be promising tools for the treatment of PTSD. Histone acetylation is involved in memory formation, and histone deacetylase (HDAC) inhibitors increase histone acetylation and subsequently enhance fear extinction. In this study, we examined whether vorinostat, an HDAC inhibitor, facilitated fear extinction, using a contextual fear conditioning (FC) paradigm. We found that vorinostat facilitated fear extinction. Next, the levels of global acetylated histone were measured by Western blotting. We also assessed the effect of vorinostat on the hippocampal levels of NMDA receptor mRNA by real-time quantitative PCR (RT-PCR). The levels of acetylated histone and NR2B mRNA, but not NR1 or NR2A mRNA, were elevated in the hippocampus 2 h after administration of vorinostat. We investigated the levels of acetylated histones and phospho-CREB (p-CREB) binding at the promoter of the NR2B gene using the chromatin immunoprecipitation (ChIP) assay followed by RT-PCR. The levels of acetylated histone and the binding of p-CREB to its binding site at the promoter of the NR2B gene were increased. These findings suggest that vorinostat in conjunction with exposure therapy can be a promising new avenue for the treatment of PTSD.


Acetyltransferases/metabolism , Extinction, Psychological/physiology , Fear/drug effects , Receptors, N-Methyl-D-Aspartate/metabolism , Stress Disorders, Post-Traumatic/drug therapy , Animals , Hydroxamic Acids/pharmacology , Male , Rats , Receptors, N-Methyl-D-Aspartate/genetics , Stress Disorders, Post-Traumatic/metabolism , Vorinostat
6.
J Psychiatr Res ; 46(5): 635-43, 2012 May.
Article En | MEDLINE | ID: mdl-22364833

Histone acetylation, which alters the compact chromatin structure and changes the accessibility of DNA to regulatory proteins, is emerging as a fundamental mechanism for regulating gene expression. Histone deacetylase (HDAC) inhibitors increase histone acetylation and enhance fear extinction. In this study, we examined whether vorinostat, an HDAC inhibitor, facilitates fear extinction, using a contextual fear conditioning (FC) paradigm, in Sprague-Dawley rats. We found that vorinostat facilitated fear extinction. Next, the levels of global acetylated histone H3 and H4 were measured by Western blotting. We also assessed the effect of vorinostat on the hippocampal levels of NMDA receptor mRNA by real-time quantitative PCR (RT-PCR) and protein by Western blotting. 2 h after vorinostat administration, the levels acetylated histones and NR2B mRNA, but not NR1 or NR2A mRNA, were elevated in the hippocampus. The NR2B protein level was elevated 4 h after vorinostat administration. Last, we investigated the levels of acetylated histones and phospho-CREB (p-CREB) binding at the promoter of the NR2B gene using the chromatin immunoprecipitation (ChIP) assay followed by RT-PCR. The ChIP assay revealed increases in the levels of acetylated histones and they were accompanied by enhanced binding of p-CREB to its binding site at the promoter of the NR2B gene 2 h after vorinostat administration. These findings suggest that vorinostat increases the expression of NR2B in the hippocampus by enhancing histone acetylation, and this process may be implicated in fear extinction.


Extinction, Psychological/drug effects , Fear/drug effects , Gene Expression Regulation/drug effects , Hippocampus/drug effects , Histone Deacetylase Inhibitors/pharmacology , Hydroxamic Acids/pharmacology , Receptors, N-Methyl-D-Aspartate/metabolism , Analysis of Variance , Animals , Behavior, Animal/drug effects , CREB-Binding Protein/metabolism , Chromatin Immunoprecipitation , Conditioning, Psychological/drug effects , Conditioning, Psychological/physiology , Exploratory Behavior/drug effects , Hippocampus/metabolism , Histones/metabolism , Male , Motor Activity/drug effects , RNA, Messenger/genetics , Rats , Rats, Sprague-Dawley , Receptors, N-Methyl-D-Aspartate/genetics , Vocalization, Animal/drug effects , Vorinostat
7.
J Psychiatr Res ; 45(4): 460-8, 2011 Apr.
Article En | MEDLINE | ID: mdl-20863519

Because the majority of patients with posttraumatic stress disorder (PTSD) exhibit long-lasting traumatic fear memory, we hypothesize that enhanced fear memory consolidation is closely involved in the pathophysiology of PTSD. Brain-derived neurotrophic factor (BDNF) and its receptor, tyrosine kinase receptor B (TrkB), are crucial for hippocampal-dependent learning and memory. In particular, differential induction of BDNF gene transcripts mediated by histone acetylation plays a role in the consolidation of fear memory. In the present study, total and exon-specific mRNA and protein levels of BDNF and TrkB in the hippocampus after contextual fear conditioning (FC) were compared between rats subjected to single prolonged stress (SPS) and sham treatment. In addition, we examined the degree of histone acetylation at the promoter of each exon of the BDNF gene by chromatin immunoprecipitation (ChIP). We previously demonstrated a significant increase in contextual freezing in SPS rats. In the present study, SPS rats also showed increased total BDNF mRNA (including exons I, IV) and BDNF protein levels in the hippocampus after FC, accompanied by increased acetylation of histone H3 and H4 at the promoter of exon I and IV relative to sham-treated rats. Furthermore, the TrkB protein levels in the hippocampus of SPS rats were significantly higher than those in sham rats. These findings suggest that the enhanced levels of BDNF as well as TrkB along with epigenetic regulation of the BDNF gene during fear memory consolidation is, at least in part, associated with long-lasting fear memory in patients with PTSD.


Brain-Derived Neurotrophic Factor/metabolism , Conditioning, Psychological/physiology , Fear , Hippocampus/metabolism , Receptor, trkB/metabolism , Signal Transduction/physiology , Stress Disorders, Post-Traumatic/pathology , Acetylation , Analysis of Variance , Animals , Brain-Derived Neurotrophic Factor/genetics , Chromatin Immunoprecipitation/methods , Disease Models, Animal , Enzyme-Linked Immunosorbent Assay/methods , Gene Expression Regulation , Histones/metabolism , Male , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Receptor, trkB/genetics , Stress Disorders, Post-Traumatic/physiopathology
8.
Seishin Shinkeigaku Zasshi ; 112(10): 986-91, 2010.
Article Ja | MEDLINE | ID: mdl-21179661

Numerous epigenetic studies have revealed that the acetylated status of histone as well as methylated status of cytosine is closely involved in gene transcription. Preclinical and clinical studies demonstrate that changes in levels of various genes in the brain including BDNF, play a role in the pathophysiology of depression. It is well known that the levels of BDNF mRNA and protein in the rat brain, such as frontal cortex and hippocampus, was decreased in response to stress, but the precise mechanism of stress-induced downregulation of BDNF has yet to be characterized. In this context, we examined the influence of a single immobilization stress (SIS) on the levels of total BDNF mRNA with each exon mRNA by real-time PCR and acetylated histone at the promoters of the BDNF gene by chromatin immunoprecipitaion assay in the rat hippocampus. SIS significantly decreased the levels of total BDNF mRNA with significant reduced levels of exon I and IV mRNA. Significant decreases in acetylated histone H3, but not H4, were found at the promoters of exons I, IV, and VI. On the other hand, antidepressant-like effects has been reported with sodium butylate (SB), a histone deacetylase (HDAC) inhibitor, promoting gene transcription. We also found antidepressant-like effect of repeated administration of SB in the forced swim test using rats. In addition, we found that upregulation in transthyretin mRNA in the rat hippocampus is, at least in part, associated with this effect using DNA microarray and real-time PCR. Based on these findings, it is postulated that epigenetic regulation of the BDNF gene by stress and antidepressants may be involved in the pathophysiology of depression.


Depression/genetics , Epigenesis, Genetic , Animals , Brain-Derived Neurotrophic Factor/genetics , Rats
9.
Biosci Biotechnol Biochem ; 74(4): 753-8, 2010.
Article En | MEDLINE | ID: mdl-20445320

Hyperpigmentations are a serious concern addressed by both the medical community and the cosmetic industry through the development of agents that block melanin biosynthesis. In this study, we found that 2-amino-3H-phenoxazin-3-one (APO), isolated from extracts of the edible mushroom Agaricus bisporus Imbach, exhibited potent inhibitory effects on melanogenesis in B16 cells, a murine melanoma cell line. APO inhibited melanin biosynthesis at 1,000 times lower concentrations (IC(50)=1.31+/-0.08 microM) than kojic acid (IC(50)=1.31+/-0.13 mM), without causing cellular toxicity. APO did not directly inhibit the enzyme activity of tyrosinase, the rate-limiting melanogenic enzyme. Further study showed that APO inhibited the protein expression of tyrosinase and microphthalmia-associated transcription factor (MITF), a melanogenic transcription factor that regulates the expression of tyrosinase. These results suggest that APO is a promising depigmenting agent with both therapeutic and cosmetic value in preventing melanogenesis.


Melanins/biosynthesis , Agaricales/metabolism , Animals , Cell Line, Tumor , Indoles , Melanins/antagonists & inhibitors , Melanins/metabolism , Melanoma/metabolism , Melanoma, Experimental/enzymology , Melanoma, Experimental/metabolism , Mice , Microphthalmia-Associated Transcription Factor/metabolism , Monophenol Monooxygenase/antagonists & inhibitors , Monophenol Monooxygenase/metabolism , Pyrones , Transcription Factors/metabolism
10.
J Psychiatr Res ; 44(15): 1069-74, 2010 Nov.
Article En | MEDLINE | ID: mdl-20427053

Previous studies have demonstrated that rats subjected to single prolonged stress (SPS) exhibit posttraumatic stress disorder (PTSD)-like symptoms, such as enhanced contextual fear in response to trauma-related and trauma-unrelated events. Furthermore, we previously reported that upregulation of hippocampal glycine transporter 1 (GlyT-1) mRNA after context exposure could be the initial mechanism underlying impaired fear extinction in SPS rats. To clarify the involvement of the hippocampal glycinergic system in impaired fear extinction in SPS rats, we measured the time course of changes in the duration of freezing and the hippocampal levels of Gly-T1 mRNA using contextual fear conditioning (FC) and extinction training. We also used in vivo microdialysis to measure the concentration of extracellular glycine in the hippocampus during the time interval between FC and the first context exposure. SPS rats exhibited increased and sustained contextual fear responses. The enhanced contextual fear response in SPS rats was associated with a sustained increase in hippocampal levels of Gly-T1 mRNA after FC relative to sham rats, and by a decrease in the extracellular glycine concentration. GlyT-1 mRNA levels in rats that underwent repeated extinction training were significantly lower than in rats that did not undergo extinction training. These findings indicate that reduced activity of the hippocampal glycinergic system could be closely involved in impaired fear extinction in SPS rats, suggesting that activation of the glycinergic system by d-cycloserine or GlyT-1 inhibitors may ameliorate the impairment of fear extinction.


Gene Expression Regulation/physiology , Glycine Plasma Membrane Transport Proteins/metabolism , Glycine/metabolism , Hippocampus/metabolism , Stress Disorders, Post-Traumatic/pathology , Analysis of Variance , Animals , Conditioning, Classical/physiology , Disease Models, Animal , Electrochemistry/methods , Fear/psychology , Glycine Plasma Membrane Transport Proteins/genetics , Male , Microdialysis/methods , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Stress Disorders, Post-Traumatic/etiology , Time Factors
11.
Psychiatry Investig ; 7(4): 251-6, 2010 Dec.
Article En | MEDLINE | ID: mdl-21253408

Neuronal plasticity induced by changes in synaptic morphology and function is well known to play a pivotal role in leaning and memory as well as adaptation to stress. It is suggested that these plastic changes are due to orchestration of alterations in gene expression in the brain. Recent advances in molecular biology have provided evidence that epigenetic mechanisms, such as DNA methylation and histone modification, are crucial to gene transcription in the mammalian brain. Our research group has recently investigated the involvement of histone actylation at the promoter of the brain-derived neurotrophic factor (BDNF) gene in stress-induced reduction in BDNF, as well as in fear conditioning-induced enhancement of BDNF, in the rat hippocampus. The results of the stress study demonstrated that single-immobilization stress significantly reduced the levels of total, exon I, and exon IV BDNF mRNA, and also significantly reduced acetylation levels of histone H3, but not H4, at the promoter of exons I, IV, and VI. The results of the fear conditioning study showed that footshock stress significantly increased the levels of total, exon I, and exon IV BDNF mRNA, with significantly increased acetylation levels of both histone H3 and H4, at the promoter of exons I and IV, followed by enhanced freezing to fear-context exposure. These findings suggest that changes in BDNF transcription in the rat hippocampus in response to stressful stimuli are, at least in part, regulated by histone acetylation status.

12.
Depress Anxiety ; 26(12): 1110-7, 2009.
Article En | MEDLINE | ID: mdl-19918929

Although selective serotonin reuptake inhibitors (SSRIs) are reported to be effective in decreasing posttraumatic stress disorder (PTSD) symptoms, a subgroup of PTSD patients remain chronically symptomatic and maintain conditioned fear responses to traumatic stimuli. In this context, the establishment of an appropriate animal model of PTSD is necessary to promote better understanding of the mechanisms of the disorder and to facilitate the development of more effective therapeutic alternatives to SSRIs. Although no single widely accepted animal model of PTSD has been established to date, the single prolonged stress (SPS) animal model has been partially validated as a model for PTSD. SPS rats mimic the pathophysiological abnormalities and behavioral characteristics of PTSD, such as enhanced anxiety-like behavior and glucocorticoid negative feedback, and they exhibit the expected therapeutic response to paroxetine on enhanced fear memory. In addition, SPS rats exhibit enhanced freezing in response to contextual fear conditioning, and impaired extinction of fear memory, which is alleviated by D-cycloserine. The enhanced consolidation and impaired extinction of fear memory found in SPS rats suggests that this model has additional value because recent studies of PTSD indicate that memory abnormalities are a central feature. In this study, we summarize the behavioral and pathophysiological PTSD-like symptoms in SPS, focusing on memory abnormalities, and evaluate the validity of SPS as an animal model of PTSD.


Disease Models, Animal , Stress Disorders, Post-Traumatic/psychology , Animals , Antidepressive Agents, Second-Generation/pharmacology , Antimetabolites/pharmacology , Arousal/drug effects , Arousal/physiology , Brain/physiopathology , Conditioning, Classical/drug effects , Conditioning, Classical/physiology , Cycloserine/pharmacology , Extinction, Psychological/drug effects , Extinction, Psychological/physiology , Fear/drug effects , Fear/physiology , Glucocorticoids/physiology , Humans , Mental Recall/drug effects , Mental Recall/physiology , Paroxetine/pharmacology , Rats , Stress Disorders, Post-Traumatic/drug therapy , Stress Disorders, Post-Traumatic/physiopathology
13.
Article Ja | MEDLINE | ID: mdl-19663264

Although the impaired extinction of traumatic memory is one of the hallmark symptoms of PTSD, the underlying mechanisms of impaired extinction are unclear and effective pharmacological interventions have not yet been developed. In this study, using rats subjected to single prolonged stress (SPS), an animal model of PTSD, we examined (a) the ability of SPS to impair fear extinction, (b) whether D-cycloserine (DCS) can alleviate impaired fear extinction in SPS rats, and (c) the effect of SPS and/or DCS on the levels of N-methyl-D-aspartate (NMDA) receptor subunit mRNAs in the rat hippocampus during extinction training. SPS rats exhibited impaired fear extinction in the contextual fear test, which was alleviated by the repeated administration of DCS. SPS induced significant upregulation of the levels of NMDA receptor subunit mRNAs before and during the period of extinction training, while repeated administration of DCS eliminated the enhanced mRNA levels of NMDARs, suggesting that DCS, irrespective of its mechanistic involvement in the enhancement of fear extinction, may help to reverse hippocampal plasticity, and thus reverse the NMDA compensatory alterations. Our research indicates that DCS may be a promising tool for the treatment of PTSD.


Extinction, Psychological , Fear/psychology , Memory , Stress Disorders, Post-Traumatic/psychology , Animals , Rats , Receptors, N-Methyl-D-Aspartate/physiology , Stress Disorders, Post-Traumatic/drug therapy
14.
Horm Behav ; 56(1): 112-20, 2009 Jun.
Article En | MEDLINE | ID: mdl-19341740

It is known that the early environment affects the mental development of rodent and human offspring. However, it is not known specifically whether a postpartum depressive state influences the depressive state in offspring. Using learned helplessness (LH) in rats as an animal model of depression, we examined the influence of maternal postpartum LH on responses to the LH test of offspring. Dam rats were judged as LH or non-helpless (nLH) on postnatal days (PN) 2-3, and maternal behavior was recorded during PN2-14. On PN 45-46, offspring were subjected to the LH test. Plasma corticosterone (CORT) levels, hippocampal levels of glucocorticoid receptor (GR) and brain-derived neurotrophic factor (BDNF) mRNA were measured before and after the LH test in offspring. Active nursing in LH dams was significantly lower than that in nLH dams. Susceptibility to LH in the offspring of LH dams was significantly higher than in those of nLH dams, and was negatively correlated with active nursing by LH dams. The GR mRNA levels before and after the LH test were lower in the offspring of LH dams than in those of nLH dams, and the reduced basal GR mRNA and protein might have resulted in the higher CORT response after the LH test. There was no significant difference in BDNF mRNA in the offspring of LH and nLH dams. These findings suggest that early postpartum LH decreased active nursing and increased depression-like behavior in the adolescent offspring via dysfunction of the hypothalamic-pituitary-adrenal axis.


Helplessness, Learned , Maternal Behavior/psychology , Postpartum Period/psychology , Animals , Anxiety/psychology , Body Weight , Brain-Derived Neurotrophic Factor/metabolism , Breast Feeding/psychology , Corticosterone/blood , Depression/psychology , Exploratory Behavior , Female , Hippocampus/metabolism , Male , Maternal Behavior/physiology , Maze Learning , Motor Activity , RNA, Messenger/metabolism , Random Allocation , Rats , Rats, Sprague-Dawley , Receptors, Glucocorticoid/metabolism
15.
J Interferon Cytokine Res ; 29(3): 161-70, 2009 Mar.
Article En | MEDLINE | ID: mdl-19196068

In this study, we describe the creation of three interferon-alpha (IFN-alpha)8 mutants with markedly higher antiviral and antiproliferative activities in comparison with those of the wild-type (wt)IFN-alpha8, wtIFN-alpha2, and IFN-con1 using a phage display system. Sequence analysis showed that three out of the six hot-spot amino acid residues of wtIFN-alpha8 known to be important for the interaction with the IFN-alpha receptor-2 (IFNAR-2)-binding sites were substituted to other amino acids and the others remained. Although affinity analysis revealed that the dissociation constant (K(D)) of IFN-alpha8 mutants was almost the same with that of wtIFN-alpha8, furthermore, the rates of association (k(a)) and dissociation (k(d)) were relatively lower. These results suggest that changes in the surface electronic charge of amino acid residues lead to changes in binding affinity and kinetics (prolonged dissociation time) toward the IFNAR-2, resulting in the modification of the biological activity. Moreover, our results demonstrate that the molecular engineering of the IFN-alpha8 provides important insight into action of IFN and also it would be useful in the development of therapeutically prominent IFN preparations than those used in clinical practice.


Amino Acid Substitution , Interferon-alpha/genetics , Interferon-alpha/metabolism , Receptor, Interferon alpha-beta/metabolism , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Binding Sites/genetics , Binding, Competitive , Cell Line, Tumor , Cell Proliferation/drug effects , Growth Inhibitors/chemistry , Growth Inhibitors/pharmacology , Hep G2 Cells , Humans , Interferon Type I/genetics , Interferon Type I/metabolism , Interferon Type I/pharmacology , Interferon-alpha/pharmacology , Kinetics , Models, Molecular , Mutation , Peptide Library , Protein Binding , Protein Conformation , Recombinant Proteins , Sindbis Virus/drug effects , Surface Plasmon Resonance , U937 Cells , Vesicular stomatitis Indiana virus/drug effects
16.
Int J Neuropsychopharmacol ; 12(1): 73-82, 2009 Feb.
Article En | MEDLINE | ID: mdl-18544182

Decreased levels of brain-derived neurotrophic factor (BDNF) in the hippocampus are implicated in the pathophysiology of major depression, although the mechanism has yet to be characterized. Epigenetic studies revealed that DNA methylation and histone modifications at the promoter of exons of the BDNF gene are the pivotal factors in the regulation of BDNF transcription. Histone acetylation regulates gene transcription through chromatin remodelling. We examined the influence of a single immobilization stress (SIS) at 2 h and 24 h afterwards on the levels of total BDNF mRNA with each exon mRNA by quantitative real-time PCR, acetylated histone at the promoters of the BDNF gene by chromatin immunoprecipitation followed by real-time PCR, and BDNF protein by ELISA in the rat hippocampus. SIS significantly decreased the levels of total BDNF mRNA with significantly reduced levels of exons I and IV mRNA followed by a significant reduction in BDNF protein 4 h after SIS. Significant decreases in the levels of acetylated histone H3, but not H4, were found at the promoters of exons I, IV, and VI. In contrast, no marked changes in the levels of either acetylated histone or BDNF mRNA and protein were found 24 h after SIS. This study demonstrated the involvement of histone acetylation in the regulation of BDNF transcription by SIS, and the plastic change in histone acetylation after SIS. These findings suggest that stress affects BDNF gene transcription via epigenetic regulation, and glucocorticoid may be involved in this regulation.


Brain-Derived Neurotrophic Factor/biosynthesis , Hippocampus/metabolism , Histones/metabolism , Restraint, Physical , Stress, Psychological/psychology , Acetylation , Animals , Brain-Derived Neurotrophic Factor/genetics , Chromatin Immunoprecipitation , Corticosterone/blood , Enzyme-Linked Immunosorbent Assay , Exons/genetics , Male , Promoter Regions, Genetic/genetics , Rats , Rats, Sprague-Dawley , Reverse Transcriptase Polymerase Chain Reaction , Stress, Psychological/metabolism , Untranslated Regions/genetics
17.
Biol Pharm Bull ; 31(10): 1938-45, 2008 Oct.
Article En | MEDLINE | ID: mdl-18827359

Accumulating evidence suggests that nitric oxide (NO) and prostaglandin E(2) (PGE(2)) are involved in the pathogenesis of various chronic inflammatory diseases and cancer. During the course of a screening program to identify natural anti-inflammatory substances, we isolated the compound 2-amino-3H-phenoxazin-3-one (APO) from an extract of the edible brown mushroom Agaricus bisporus IMBACH. APO inhibited NO production by mouse peritoneal macrophages in response to the pro-inflammatory stimuli lipopolysaccharide (LPS) and interferon (IFN)-gamma (LPS/IFN-gamma) at low concentrations (IC(50)=1.5 microM) through reduced inducible NO synthase protein expression. PGE(2) production by LPS/IFN-gamma-stimulated macrophages was inhibited by APO at much lower concentrations (IC(50)=0.27 microM) than those required for the inhibition of NO production. Mechanistic analysis showed that APO inhibited both cyclooxygenase (COX)-1 and COX-2 enzyme activities with almost equal selectivity. Secretion of NO and the pro-inflammatory cytokine IL-6 by IFN-gamma-activated RAW264.7 cells, a murine macrophage-like cell line, was also dose-dependently reduced by APO. Furthermore, APO increased the secretion of the anti-inflammatory cytokine IL-4 by antigen-stimulated T cells and promoted the polarization of CD4(+) Th cells toward the anti-inflammatory Th2 phenotype at equimolar concentrations that inhibited NO production. Our results suggested that APO induced polarization toward the Th2 subset, at least in part through the down-regulation of IL-12 production. Thus, APO appears to have potent anti-inflammatory and immunoregulatory properties that may provide a promising therapeutic strategy for the treatment of T cell-mediated inflammatory autoimmune diseases as well as for bacteria-induced chronic-inflammatory diseases.


Anti-Inflammatory Agents, Non-Steroidal/isolation & purification , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Aromatase Inhibitors/pharmacology , Immunologic Factors/isolation & purification , Immunologic Factors/pharmacology , Oxazines/pharmacology , Agaricales/chemistry , Animals , CD4 Antigens/biosynthesis , Cell Differentiation/drug effects , Cells, Cultured , Cytokines/biosynthesis , Dinoprostone/biosynthesis , Female , Indicators and Reagents , Macrophages, Peritoneal/drug effects , Mice , Mice, Inbred BALB C , Nitric Oxide/biosynthesis , Nitric Oxide Synthase Type II/biosynthesis , Prostaglandin-Endoperoxide Synthases/biosynthesis , T-Lymphocytes/drug effects , T-Lymphocytes/metabolism , Th2 Cells/drug effects
18.
Neuropsychopharmacology ; 33(9): 2108-16, 2008 Aug.
Article En | MEDLINE | ID: mdl-17957211

Although the impaired extinction of traumatic memory is one of the hallmark symptoms of posttraumatic stress disorder (PTSD), the underlying mechanisms of impaired extinction are unclear and effective pharmacological interventions have not yet been developed. Single prolonged stress (SPS) has been proposed as an animal model of PTSD, since rats subjected to SPS (SPS rats) show enhanced negative feedback of the HPA axis and increased contextual fear, which are characteristics similar to those observed in patients with PTSD. In this study, using SPS rats, we examined (a) the ability of SPS to impair fear extinction, (b) whether D-cycloserine (DCS) can alleviate impaired fear extinction in SPS rats, and (c) the effect of SPS and/or DCS on the levels of N-methyl-D-aspartate (NMDA) receptor subunit mRNAs in the rat hippocampus during extinction training. SPS rats exhibited impaired fear extinction in the contextual fear test, which was alleviated by the repeated administration of DCS. The effect of enhanced extinction, induced by the administration of DCS to SPS rats, was maintained for one week following extinction training. SPS induced significant upregulation of the levels of NMDA receptor subunit mRNAs before and during the period of extinction training, while repeated administration of DCS eliminated the enhanced mRNA levels of NMDARs. Behavioral analyses indicated that SPS is an appropriate animal model of PTSD and that DCS may be effective in the treatment of PTSD. These findings suggest that DCS, irrespective of its mechanistic involvement in the enhancement of fear extinction, may help to reverse hippocampal plasticity, and thus reverse the NMDA compensatory alterations.


Antimetabolites/pharmacology , Cycloserine/pharmacology , Extinction, Psychological/drug effects , Fear , Hippocampus/metabolism , Receptors, N-Methyl-D-Aspartate/metabolism , Stress Disorders, Post-Traumatic , Stress, Psychological/complications , Analysis of Variance , Animals , Behavior, Animal , Disease Models, Animal , Electroshock/adverse effects , Gene Expression Regulation/drug effects , Male , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Receptors, N-Methyl-D-Aspartate/genetics , Stress Disorders, Post-Traumatic/etiology , Stress Disorders, Post-Traumatic/metabolism , Stress Disorders, Post-Traumatic/pathology
19.
J Interferon Cytokine Res ; 27(6): 517-23, 2007 Jun.
Article En | MEDLINE | ID: mdl-17572016

Although there are at least 13 interferon-alpha (IFN-alpha) subtypes in humans, interactions between the subtypes remain unknown. To understand IFN-alpha interactions, we examined the antiproliferative activities and the receptor binding affinities of different combinations of IFN-alpha2 and IFN-alpha8 using six renal cell carcinoma (RCC) cell lines. Although IFN-alpha8 was the more potent subtype, synergistic and antagonistic antiproliferative effects were also observed in certain combinations of IFN-alpha2 and IFN-alpha8. To analyze the interactions between IFN-alpha2 and IFN-alpha8, the receptor-binding kinetics of different combinations of IFN-alpha2 and IFN- alpha8 to the IFN-alpha receptors, IFNAR-1 or IFNAR-2, were measured using a surface plasmon resonance-based biosensor. Unexpectedly, the receptor binding kinetics to IFNAR-2 but not to IFNAR-1 were mutually related to antiproliferative activity and increase in the binding speed (K(a)) for IFNAR-2. Moreover, we observed the increased fluorescence intensity (FI) of biotin-labeled IFN-alpha8 to IFNAR-2 by receptor binding inhibition assay with unlabeled IFN-alpha2 but not the other combinations. These findings indicate that the binding manner of IFN-alpha8 for IFNAR-2 is different from that of IFN-alpha2, suggesting that binding of IFN-alpha8 rather than binding of IFN-alpha2 to IFNAR-2 leads to activation and subsequent antiproliferative activity despite the same antiviral activity in RCC.


Carcinoma, Renal Cell/metabolism , Carcinoma, Renal Cell/pathology , Interferon-alpha/pharmacology , Receptor, Interferon alpha-beta/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Humans , Interferon-alpha/classification , Kinetics
20.
Eur J Neurosci ; 25(3): 815-29, 2007 Feb.
Article En | MEDLINE | ID: mdl-17328777

Rodent studies have revealed that the early rearing environment plays an important role in the development of stress vulnerability, memory and cognition. Although early lighting conditions (ELC) are involved in these neuronal developments through both maternal and offspring behavior, their influence has not been fully elucidated. Thus, by using Sprague-Dawley rats, we examined whether ELC affected maternal care by the dam and the subsequent neurodevelopment of the offspring. Prolonged dark phase conditions (PDC) (light/dark, 6/18 h) and prolonged light phase conditions (light/dark, 18/6 h) were administered from postnatal day 2 to postnatal day 14. Throughout this period, maternal care and the circadian rhythmicity of dams were investigated. In adolescence and adulthood of the offspring, we measured anxiety-like behavior, social interaction, object recognition memory, activity rhythm and corticosterone response to stress with hippocampal expression of N-methyl-D-aspartate and glucocorticoid receptor mRNAs. PDC altered maternal care and circadian rhythmicity in the dam compared with normal lighting conditions and prolonged light phase conditions. PDC markedly increased anxiety-like behavior, decreased social interaction and object recognition memory, and inhibited corticosterone feedback in offspring later in life. Furthermore, hippocampal levels of glucocorticoid receptor mRNA and N-methyl-D-aspartate receptor 2B mRNA in rats subjected to PDC were significantly lower than in animals subjected to normal lighting conditions. In the adult offspring, the circadian rhythm of locomotor activity was not affected. These findings suggested that ELC affect mother-infant interactions and subsequently at least partially alter the neurobehavioral development of offspring.


Anxiety/physiopathology , Hippocampus/growth & development , Lighting , Maternal Behavior/physiology , Memory/physiology , Age Factors , Animals , Anxiety/etiology , Circadian Rhythm/physiology , Corticosterone/blood , Darkness , Environment , Female , Hippocampus/physiology , Motor Activity/physiology , Phenotype , Pregnancy , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Receptors, Glucocorticoid/genetics , Receptors, N-Methyl-D-Aspartate/genetics , Social Behavior
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