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1.
Front Immunol ; 15: 1387808, 2024.
Article in English | MEDLINE | ID: mdl-38745656

ABSTRACT

Background: Tuberculous meningitis (TBM) is a devastating form of tuberculosis (TB) causing high mortality and disability. TBM arises due to immune dysregulation, but the underlying immune mechanisms are unclear. Methods: We performed single-cell RNA sequencing on peripheral blood mononuclear cells (PBMCs) and cerebrospinal fluid (CSF) cells isolated from children (n=6) with TBM using 10 xGenomics platform. We used unsupervised clustering of cells and cluster visualization based on the gene expression profiles, and validated the protein and cytokines by ELISA analysis. Results: We revealed for the first time 33 monocyte populations across the CSF cells and PBMCs of children with TBM. Within these populations, we saw that CD4_C04 cells with Th17 and Th1 phenotypes and Macro_C01 cells with a microglia phenotype, were enriched in the CSF. Lineage tracking analysis of monocyte populations revealed myeloid cell populations, as well as subsets of CD4 and CD8 T-cell populations with distinct effector functions. Importantly, we discovered that complement-activated microglial Macro_C01 cells are associated with a neuroinflammatory response that leads to persistent meningitis. Consistently, we saw an increase in complement protein (C1Q), inflammatory markers (CRP) and inflammatory factor (TNF-α and IL-6) in CSF cells but not blood. Finally, we inferred that Macro_C01 cells recruit CD4_C04 cells through CXCL16/CXCR6. Discussion: We proposed that the microglial Macro_C01 subset activates complement and interacts with the CD4_C04 cell subset to amplify inflammatory signals, which could potentially contribute to augment inflammatory signals, resulting in hyperinflammation and an immune response elicited by Mtb-infected tissues.


Subject(s)
Microglia , Single-Cell Analysis , Transcriptome , Tuberculosis, Meningeal , Humans , Tuberculosis, Meningeal/immunology , Microglia/immunology , Microglia/metabolism , Child , Male , Female , Child, Preschool , Cytokines/metabolism , Complement Activation/immunology , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/metabolism , Gene Expression Profiling , Mycobacterium tuberculosis/immunology
2.
Expert Rev Anti Infect Ther ; 21(12): 1355-1364, 2023.
Article in English | MEDLINE | ID: mdl-37970631

ABSTRACT

INTRODUCTION: Tuberculosis (TB) is a chronic infectious disease caused by mycobacterium tuberculosis (Mtb) that poses a major threat to human health. AREAS COVERED: Herein, we aim to review the alteration of the microbiota in gut and respiratory during TB development, the potential function and mechanisms of microbiota in the pathogenesis of Mtb infection, and the impact of antibiotic treatment on the microbiota. In addition, we discuss the potential new paradigm for the use of microbiota-based treatments such as probiotics and prebiotics in the treatment of TB. EXPERT OPINION: Studies have shown that trillions of micro-organisms live in the human gut and respiratory tract, acting as gatekeepers in maintaining immune homeostasis and respiratory physiology and playing a beneficial or hostile role in the development of TB. Anti-TB antibiotics may cause microecological imbalances in the gut and respiratory tract, and microbiome-based therapeutics may be a promising strategy for TB treatment. Appropriate probiotics and prebiotics supplementation, along with antimycobacterial treatment, will improve the therapeutic effect of TB treatment and protect the gut and respiratory microbiota from dysbiosis.


Subject(s)
Microbiota , Mycobacterium tuberculosis , Probiotics , Tuberculosis, Pulmonary , Tuberculosis , Humans , Tuberculosis, Pulmonary/drug therapy , Tuberculosis/drug therapy , Lung/microbiology , Mycobacterium tuberculosis/physiology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Probiotics/therapeutic use , Prebiotics , Dysbiosis/microbiology
4.
J Inflamm Res ; 15: 3285-3304, 2022.
Article in English | MEDLINE | ID: mdl-35676971

ABSTRACT

Background and Purpose: Celastrol (CS) is a major active ingredient of the Chinese/Asian herb Tripterygium wilfordii that is frequently used as phytomedicine to treat inflammation and autoimmune diseases. We showed before that short-term exposure to CS (1 µM) favorably impacts the biosynthesis of inflammation-related lipid mediators (LM) in human polarized macrophages by modulating the activities of different lipoxygenases (LOXs). However, whether CS regulates the expression of LOXs and other related LM-biosynthetic enzymes during macrophage polarization is unknown. Here, we investigated how CS affects LM-biosynthetic enzyme expression on the protein level and studied concomitant LM signature profiles during polarization of human monocyte-derived macrophages (MDM) towards M1- and M2-like phenotypes. Methods and Results: We used LM metabololipidomics to study the long-term effects of CS on LM profile signatures after manipulation of human monocyte-derived macrophages (MDM) during polarization. Exposure of MDM to low concentrations of CS (ie, 0.2 µM) during polarization to an inflammatory M1 phenotype potently suppressed the formation of pro-inflammatory cyclooxygenase (COX)- and 5-LOX-derived LM, especially prostaglandin (PG)E2. Notably, gene and enzyme expression of COX-2 and microsomal PGE2 synthase (mPGES)-1 as well as M1 markers were strongly decreased by CS during M1-MDM polarization, along with impaired activation of nuclear factor-κB and p38 mitogen-activated protein kinase. During IL-4-induced M2 polarization, CS decreased the capacity of the resulting M2-MDM to generate pro-inflammatory COX and 5-LOX products as well but it also reduced the formation of 12/15-LOX products and specialized pro-resolving mediators, without affecting the levels of liberated fatty acid substrates. Conclusion: Depending on the timing and concentration, CS not only favorably affects LOX activities in macrophages but also the expression of LM-biosynthetic enzymes during macrophage polarization connected to changes of inflammation-related LM which might be of relevance for potential application of CS to treat inflammatory disorders.

5.
Front Immunol ; 13: 849583, 2022.
Article in English | MEDLINE | ID: mdl-35663935

ABSTRACT

Macrophages are the primary human host cells of intracellular Mycobacterium tuberculosis (M.tb) infection, where the magnitude of inflammatory reactions is crucial for determining the outcome of infection. Previously, we showed that the anti-inflammatory drug sulfasalazine (SASP) significantly reduced the M.tb bactericidal burden and histopathological inflammation in mice. Here, we asked which genes in human inflammatory macrophages are affected upon infection with M.tb and how would potential changes impact the functional state of macrophages. We used a flow cytometry sorting system which can distinguish the dead and alive states of M.tb harbored in human monocyte-derived macrophages (MDM). We found that the expression of cyclooxygenase-2 and microsomal prostaglandin E2 synthase (mPGES)-1 increased significantly in tagRFP+ MDM which were infected with alive M.tb. After exposure of polarized M1-MDM to M.tb (H37Rv strain)-conditioned medium (MTB-CM) or to the M.tb-derived 19-kD antigen, the production of PGE2 and pro-inflammatory cytokines increased 3- to 4-fold. Upon treatment of M1-MDM with SASP, the MTB-CM-induced expression of COX-2 and the release of COX products and cytokines decreased. Elevation of PGE2 in M1-MDM upon MTB-CM stimulation and modulation by SASP correlated with the activation of the NF-κB pathway. Together, infection of human macrophages by M.tb strongly induces COX-2 and mPGES-1 expression along with massive PGE2 formation which is abrogated by the anti-inflammatory drug SASP.


Subject(s)
Mycobacterium tuberculosis , Tuberculosis, Lymph Node , Animals , Anti-Inflammatory Agents/metabolism , Cyclooxygenase 2/metabolism , Cytokines/metabolism , Dinoprostone/metabolism , Humans , Inflammation/metabolism , Macrophages , Mice , Mycobacterium tuberculosis/physiology , Sulfasalazine/pharmacology , Up-Regulation
6.
J Leukoc Biol ; 111(5): 1021-1029, 2022 05.
Article in English | MEDLINE | ID: mdl-34533236

ABSTRACT

Tuberculosis (TB), an infectious bacterial disease caused by Mycobacterium tuberculosis (Mtb), is a major cause of death worldwide. Multidrug-resistant TB remains a public health crisis and thus novel effective treatments, such as host-directed therapies (HDTs), are urgently required to overcome the challenges of TB infection. In this study, we evaluated 4 calcium modulators for their effects on Mtb growth in macrophages. Only flunarizine enhanced the bactericidal ability of macrophages against Mtb, which was induced by an increase in phosphorylated calcium/calmodulin (CaM)-dependent protein kinase II (pCaMKII) levels. We further discovered that the expression of CaM was decreased in Mtb-infected macrophages and restored following flunarizine treatment; this was associated with phagolysosome maturation and acidification. Consistent with these findings, the anti-TB ability of macrophages was reduced following the silencing of CaM or inhibition of CAMKII activity. In conclusion, our results demonstrated that flunarizine enhanced the bactericidal ability of macrophages and clarified its CaM-pCAMKII-dependent mechanism. Therefore, our findings strongly support further studies of this currently approved drug as an HDT candidate for TB therapy.


Subject(s)
Mycobacterium tuberculosis , Tuberculosis , Anti-Bacterial Agents/pharmacology , Calcium/metabolism , Calmodulin/metabolism , Flunarizine/pharmacology , Humans , Phagosomes/metabolism , Tuberculosis/microbiology
7.
Biomolecules ; 11(5)2021 05 17.
Article in English | MEDLINE | ID: mdl-34067705

ABSTRACT

Tripterygium wilfordii glycosides (TWG) is a traditional Chinese medicine with effectiveness against rheumatoid arthritis (RA), supported by numerous clinical trials. Lipid mediators (LM) are biomolecules produced from polyunsaturated fatty acids mainly by cyclooxygenases (COX) and lipoxygenases (LOX) in complex networks which regulate inflammation and immune responses and are strongly linked to RA. The mechanism by which TWG affects LM networks in RA treatment remains elusive. Employing LM metabololipidomics using ultra-performance liquid chromatography-tandem mass spectrometry revealed striking modulation of LM pathways by TWG in human monocyte-derived macrophage (MDM) phenotypes. In inflammatory M1-MDM, TWG (30 µg/mL) potently suppressed agonist-induced formation of 5-LOX products which was confirmed in human PMNL and traced back to direct inhibition of 5-LOX (IC50 = 2.9 µg/mL). TWG also efficiently blocked thromboxane formation in M1-MDM without inhibiting other prostanoids and COX enzymes. Importantly, in anti-inflammatory M2-MDM, TWG (30 µg/mL) induced pronounced formation of specialized pro-resolving mediators (SPM) and related 12/15-LOX-derived SPM precursors, without COX and 5-LOX activation. During MDM polarization, TWG (1 µg/mL) decreased the capacity to generate pro-inflammatory 5-LOX and COX products, cytokines and markers for M1 phenotypes. Together, suppression of pro-inflammatory LM but SPM induction may contribute to the antirheumatic properties of TWG.


Subject(s)
Antirheumatic Agents/administration & dosage , Arachidonate 5-Lipoxygenase/metabolism , Glycosides/pharmacology , Prostaglandin-Endoperoxide Synthases/metabolism , Tripterygium/chemistry , A549 Cells , Antirheumatic Agents/pharmacology , Chromatography, High Pressure Liquid , Gene Expression Regulation/drug effects , Humans , Immunity, Innate/drug effects , Lipidomics/methods , Macrophages/drug effects , Macrophages/metabolism , Prostaglandins/metabolism , Tandem Mass Spectrometry , Thromboxanes
8.
Pharmacol Res ; 167: 105556, 2021 05.
Article in English | MEDLINE | ID: mdl-33812006

ABSTRACT

The pentacyclic triterpenoid quinone methide celastrol (CS) from Tripterygium wilfordii Hook. F. effectively ameliorates inflammation with potential as therapeutics for inflammatory diseases. However, the molecular mechanisms underlying the anti-inflammatory and inflammation-resolving features of CS are incompletely understood. Here we demonstrate that CS potently inhibits the activity of human 5-lipoxygenase (5-LOX), the key enzyme in pro-inflammatory leukotriene (LT) formation, in cell-free assays with IC50 = 0.19-0.49 µM. Employing metabololipidomics using ultra-performance liquid chromatography coupled to tandem mass spectrometry in activated human polymorphonuclear leukocytes or M1 macrophages we found that CS (1 µM) potently suppresses 5-LOX-derived products without impairing the formation of lipid mediators (LM) formed by 12-/15-LOXs as well as fatty acid substrate release. Intriguingly, CS induced the generation of 12-/15-LOX-derived LM including the specialized pro-resolving mediator (SPM) resolvin D5 in human M2 macrophages. Finally, intraperitoneal pre-treatment of mice with 10 mg/kg CS strongly impaired zymosan-induced LT formation and simultaneously elevated the levels of SPM and related 12-/15-LOX-derived LM in peritoneal exudates, spleen and plasma in vivo. Conclusively, CS promotes a switch from LT biosynthesis to formation of SPM which may underlie the anti-inflammatory and inflammation-resolving effects of CS, representing an interesting pharmacological strategy for intervention with inflammatory disorders.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Leukotrienes/metabolism , Lipid Metabolism/drug effects , Lipoxygenase Inhibitors/pharmacology , Pentacyclic Triterpenes/pharmacology , Animals , Anti-Inflammatory Agents/chemistry , Arachidonate 5-Lipoxygenase/metabolism , Biosynthetic Pathways/drug effects , Cells, Cultured , Humans , Inflammation/drug therapy , Inflammation/metabolism , Lipoxygenase Inhibitors/chemistry , Male , Mice , Molecular Docking Simulation , Pentacyclic Triterpenes/chemistry , Tripterygium/chemistry
9.
mSphere ; 5(2)2020 04 08.
Article in English | MEDLINE | ID: mdl-32269154

ABSTRACT

Tuberculosis (TB) is still the leading killer caused by Mycobacterium tuberculosis infection. There is a clear need for new treatment strategy against TB. It has been reported that tamoxifen, known as a selective estrogen receptor modulator (SERM), exhibits antimycobacterial activity and inhibits M. tuberculosis growth in macrophages. However, it remains unknown whether such antimicrobial activity is a general property of all SERMs and how it works. In this study, we identified that bazedoxifene (BZA), a newer SERM, inhibits intracellular M. tuberculosis growth in macrophages. BZA treatment increases autophagosome formation and LC3B-II protein expression in M. tuberculosis-infected macrophages. We further demonstrated that the enhancement of autophagy by BZA is dependent on increased reactive oxygen species (ROS) production and associated with phosphorylation of Akt/mTOR signaling. In summary, our data reveal a previously unappreciated antimicrobial function of BZA and suggest that future investigation focusing on the mechanism of action of SERMs in macrophages may lead to new host-directed therapies against TB.IMPORTANCE Since current strategies for the treatment of multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) have low efficacy and highly negative side effects, research on new treatments including novel drugs is essential for curing drug-resistant tuberculosis. Host-directed therapy (HDT) has become a promising idea to modulate host cell responses to enhance protective immunity against pathogens. Bazedoxifene (BZA), which belongs to a new generation of SERMs, shows the ability to inhibit the growth of M. tuberculosis in macrophages and is associated with autophagy. Our findings reveal a previously unrecognized antibacterial function of BZA. We propose that the mechanism of SERMs action in macrophages may provide a new potential measure for host-directed therapies against TB.


Subject(s)
Anti-Bacterial Agents/pharmacology , Autophagy/drug effects , Indoles/pharmacology , Macrophages/drug effects , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/growth & development , Humans , Macrophages/microbiology , Signal Transduction/drug effects , THP-1 Cells , Tuberculosis/drug therapy
10.
J Leukoc Biol ; 106(3): 749-757, 2019 09.
Article in English | MEDLINE | ID: mdl-31254317

ABSTRACT

Depression is a major mental health condition and is expected be the most debilitating and widespread health disorder by 2030. Tuberculosis (TB) is also a leading cause of morbidity and mortality worldwide and interestingly, is a common comorbidity of depression. As such, much attention has been paid to the association between these 2 pathologies. Based on clinical reports, the association between TB and depression seems to be bidirectional, with a substantial overlap in symptoms between the 2 conditions. TB infection or reactivation may precipitate depression, likely as a consequence of the host's inflammatory response and/or dysregulation of the hypothalamic-pituitary-adrenal axis. Nevertheless, few studies have considered whether patients with depression are at a higher risk for TB. In this review, we discuss the hypotheses on the association between depression and TB, highlighting the immuno-inflammatory response and lipid metabolism as potential mechanisms. Improving our understanding of the interplay between these 2 disorders should help guide TB clinical care and prevention both in patients with comorbid depression and in the general population.


Subject(s)
Depression/complications , Tuberculosis/complications , Tuberculosis/psychology , Disease Susceptibility , Humans , Immunity , Lipid Metabolism , Prevalence , Tuberculosis/epidemiology , Tuberculosis/immunology
11.
Biomed Res Int ; 2019: 9537050, 2019.
Article in English | MEDLINE | ID: mdl-31093505

ABSTRACT

BACKGROUND: Because of the similarity of intestinal tuberculosis and Crohn's disease in disease phenotype, differential diagnosis has always been a clinical problem. Arachidonic acid metabolites play an important role in the inflammatory response of intestinal tuberculosis and Crohn's disease. Recent studies have shown that the polymorphism locus in the promoter region of LTA4H gene affects LTB4 expression level and the susceptibility to extrapulmonary tuberculosis. Thus, we identified a total of 148 patients with intestinal tuberculosis, 145 with Crohn's disease, and 700 normal controls in this study. METHODS: All the study participants were local Han people from Jiangxi Province in the past eleven years. DNA was extracted from the paraffin-embedded specimens or the whole blood. The LTA4H promoter SNP (rs17525495) was genotyped with TaqMan assay. RESULTS: The T-alleles frequency was not significantly increased in patients with intestinal tuberculosis compared with healthy control group (p=0.630; OR=1.07; 95%CI=0.81-1.41), while patients with Crohn's disease have significantly increased T allele frequency compared with healthy population (p=0.032; OR=1.34; 95%CI=1.03-1.75). During treatment, the presence of the T allele significantly increased the proportion of Crohn's patients requiring glucocorticoids (p<0.05). CONCLUSIONS: The T allele of LTA4H gene SNP (rs17525495) is a risk factor for Crohn's disease instead of intestinal tuberculosis. More importantly, there may be a potential association of the different genotypes of rs17525495 with the treatment efficacy of 5-ASA and glucocorticoids in patients with Crohn's disease. The association between LTA4H polymorphism and drugs therapeutic effects might contribute to the practice of precision medicine and the prediction of clinical outcomes.


Subject(s)
Asian People/genetics , Crohn Disease/genetics , Epoxide Hydrolases/genetics , Ethnicity/genetics , Genetic Association Studies , Genetic Predisposition to Disease , Polymorphism, Single Nucleotide/genetics , Tuberculosis, Gastrointestinal/genetics , Adult , Crohn Disease/enzymology , Female , Gene Frequency/genetics , Humans , Male , Models, Genetic , Tuberculosis, Gastrointestinal/enzymology
12.
Fish Shellfish Immunol ; 78: 233-237, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29684609

ABSTRACT

Penaeidins are a unique family of antimicrobial peptides specific to penaeid shrimp and have been reported mainly function as anti-bacterial and anti-fungal. In order to investigate whether penaeidins could also respond to virus or not, we examined the effect of WSSV on MjPen-II (penaeidin in kuruma shrimp, Marsupenaeus japonicus) expression. In the control group, MjPen-II transcript level can be detected in almost all test tissues but was expressed most strongly in hemocytes. After WSSV infection, MjPen-II transcript level was significantly downregulated in hemocytes. Moreover, the proportion of MjPen-II+ hemocytes was not significantly different between non-infected and WSSV-infected shrimp, but the number of MjPen-II+ highly expressing hemocytes decreased after infection. In addition, MjPen-II was observed in the cytoplasm of granule-containing hemocytes. These results suggest that WSSV suppresses MjPen-II expression in hemocytes.


Subject(s)
Immunity, Innate , Penaeidae/genetics , Penaeidae/immunology , Peptides/genetics , Peptides/immunology , White spot syndrome virus 1/physiology , Animals , Antimicrobial Cationic Peptides/genetics , Antimicrobial Cationic Peptides/immunology , Arthropod Proteins/genetics , Arthropod Proteins/immunology , Hemocytes/metabolism
13.
Fish Shellfish Immunol ; 77: 46-52, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29567134

ABSTRACT

cDNA of a newly recognized white spot syndrome virus (WSSV)-induced gene (MjVIG1) was characterized from Marsupenaeus japonicus hemocytes; this gene encodes a protein that lack similarity to any known characterized protein. To identify this novel gene, we mainly conducted transcript level analysis, immunostaining and flow cytometry after WSSV infection. MjV1G1 transcript levels were also measured after Yellow head virus (YHV) and Vibrio parahaemolyticus infection tests. In non-infected and WSSV-infected shrimp, MjVIG1 was observed in granule-containing hemocytes. In addition, the MjVIG1 transcript level and ratio of MjVIG1-positive hemocytes both significantly increased, and number of MjVIG1-positive hemocytes slightly increased after WSSV infection. In contrast, MjVIG1 transcript level did not change after YHV and V. parahaemolyticus infection. These results indicated that MjVIG1 might be a WSSV-specific induced gene in M. japonicus hemocytes.


Subject(s)
Arthropod Proteins/genetics , Arthropod Proteins/immunology , Penaeidae/genetics , Penaeidae/immunology , White spot syndrome virus 1/physiology , Animals , Arthropod Proteins/metabolism , Hemocytes/immunology , Hemocytes/metabolism , Penaeidae/metabolism , Roniviridae/physiology , Vibrio parahaemolyticus/physiology
14.
J Chem Phys ; 140(9): 094902, 2014 Mar 07.
Article in English | MEDLINE | ID: mdl-24606377

ABSTRACT

Using two-dimensional Langevin dynamics simulations, we investigate the dynamics of polymer translocation into a confined space under a driving force through a nanopore, with particular emphasis on the chain stiffness and the shape of the confinement. We observe that with increasing the chain stiffness κ, the translocation time τ always increases for different shapes of confinements. For an ellipse, τ is different for the translocation through its minor and major axis directions. Under the weak confinement, the translocation through the minor axis direction is faster than that through the major axis direction for different κ, while this is true only for high κ under strong confinement. Particularly, for both weak and strong confinements we find that packaging into an ellipse through its minor axis direction is faster than that for a circle of the same area for high κ. These results are interpreted by the chain conformation during the translocation process and the time of an individual segment passing through the pore.


Subject(s)
Molecular Dynamics Simulation , Polymers/chemistry , Anisotropy
15.
J Chem Phys ; 136(18): 185103, 2012 May 14.
Article in English | MEDLINE | ID: mdl-22583312

ABSTRACT

Using Langevin dynamics simulations, we investigate the dynamics of polymer translocation into a circular nanocontainer through a nanopore under a driving force F. We observe that the translocation probability initially increases and then saturates with increasing F, independent of φ, which is the average density of the whole chain in the nanocontainer. The translocation time distribution undergoes a transition from a Gaussian distribution to an asymmetric distribution with increasing φ. Moreover, we find a nonuniversal scaling exponent of the translocation time as chain length, depending on φ and F. These results are interpreted by the conformation of the translocated chain in the nanocontainer and the time of an individual segment passing through the pore during translocation.


Subject(s)
Models, Molecular , Motion , Nanopores , Polymers/chemistry , Normal Distribution , Probability , Time Factors
16.
Mol Pain ; 4: 57, 2008 Nov 17.
Article in English | MEDLINE | ID: mdl-19014677

ABSTRACT

BACKGROUND: Clinical observation and experimental studies have indicated that a single exposure to morphine could induce tolerance and dependence. It has become a concern in clinical antinociceptive practice. However, the underling mechanism remains unknown. This study was designed to explore the changes of dopamine (DA) neuron activities in the ventral tegmental area (VTA) by employing a spectral analysis followed single morphine treatment. RESULTS: Acute morphine treatment significantly increased not only the firing rate and firing population but also the power of slow oscillation of DA neurons in naïve rats. These changes lasted at least for 3 days following the morphine treatment. During this period of time, responses of the DA neurons to subsequent morphine challenge were diminished. We further demonstrated a transient desensitization of opiate receptors as monitored by GTPgammaS binding to G-proteins. The present study provided first direct evidence for the temporal changes in the VTA DA neuron activities and opiate receptors desensitization. CONCLUSION: Prolonged VTA DA neuron activation and opiate receptors desensitization followed single morphine exposure may underlie the development of dependence and tolerance that may associate with the acute analgesic tolerance and acute addiction of morphine.


Subject(s)
Dopamine , Morphine/pharmacology , Neurons/drug effects , Animals , Drug Tolerance , Morphine/administration & dosage , Rats , Receptors, Opioid/drug effects , Substance-Related Disorders/etiology , Time Factors
17.
Biol Psychiatry ; 62(6): 687-93, 2007 Sep 15.
Article in English | MEDLINE | ID: mdl-17343834

ABSTRACT

BACKGROUND: Attentional deficits accompany many psychiatric disorders, underscoring the need for rodent models of attention to screen novel therapeutic agents and characterize the biological basis of attention. The five-choice serial reaction time task (5CSRTT) is one such model. Here, we characterized the effects of four standard psychotropic agents on performance in the 5CSRTT. METHODS: Male Sprague-Dawley rats were trained in the 5CSRTT (5-sec inter-trial interval and .5-sec stimulus duration) until they reliably performed at > 60% accuracy and < 20% omissions. They were then treated systemically with the stimulant methylphenidate (MPH) (.063-2.0 mg/kg), the N-methyl-D-aspartate antagonist dizocilpine (MK-801) (.008-.25 mg/kg), the norepinephrine reuptake inhibitor desipramine (DMI) (.63-10 mg/kg), or the kappa-receptor agonist U69,593 (.25-2.0 mg/kg) 30 min before testing. RESULTS: Methylphenidate (.5 mg/kg) increased accuracy. Dizocilpine impaired accuracy (.25 mg/kg), increased premature responses (.063-.25 mg/kg), and increased omissions (.25 mg/kg). Desipramine decreased premature responses (5.0 mg/kg) but increased omissions (10 mg/kg), correct response latencies (5.0-10.0 mg/kg), and reward latencies (5.0-10.0 mg/kg). The kappa-opioid agonist U69,593 (1.0-2.0 mg/kg) increased omissions and correct response latencies. CONCLUSIONS: In Sprague-Dawley rats, psychotropic drugs with distinct pharmacological profiles produced distinguishable effects in the 5CSRTT. The effects of these classes of drugs under our testing conditions are qualitatively similar to their effects in humans.


Subject(s)
Attention/drug effects , Behavior, Animal/drug effects , Psychomotor Performance/drug effects , Psychotropic Drugs/pharmacology , Reaction Time/drug effects , Animals , Benzeneacetamides/pharmacology , Choice Behavior/drug effects , Desipramine/pharmacology , Dizocilpine Maleate/pharmacology , Dose-Response Relationship, Drug , Male , Methylphenidate/pharmacology , Photic Stimulation , Pyrrolidines/pharmacology , Rats , Rats, Sprague-Dawley , Sensitivity and Specificity , Serial Learning/drug effects
18.
Synapse ; 59(2): 92-100, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16270300

ABSTRACT

Antipsychotic drugs are often prescribed to juvenile psychiatric patients, though their cerebral effects during development are incompletely described. Accordingly, we studied the effects of repeated treatment with dissimilar antipsychotic drugs on dopamine (DA) receptors in juvenile vs. adult rats. Tissue levels of DA receptor types (D1, D2, D3, and D4) in forebrain regions of juvenile rats were quantified after 3 weeks of daily treatment with representative first- (fluphenazine) and second-generation (clozapine and olanzapine) antipsychotics, and compared with similarly treated adult rats examined in previous studies. Fluphenazine, clozapine, and olanzapine all decreased D1 receptors in dorsolateral frontal and medial prefrontal cortex (MPC) of juvenile, but not adult rats. Conversely, all three test agents increased D2 labeling in MPC of adult, but not young animals. Fluphenazine and olanzapine, but not clozapine, also increased D2 receptor levels in hippocampus, and D4 levels in nucleus accumbens (NAc) and caudate-putamen (CPu) in both juvenile and adult brain. D3 receptors were not altered by any treatment in any brain region at either age. Only some DA receptor adaptations to antipsychotic treatment are shared by developing and mature animals. Developmental differences in DA receptor responses may account for differences in clinical effects of antipsychotic drugs between young and adult psychiatric patients.


Subject(s)
Antipsychotic Agents/pharmacology , Prosencephalon/drug effects , Receptors, Dopamine/drug effects , Age Factors , Animals , Autoradiography , Benzodiazepines/pharmacology , Clozapine/pharmacology , Fluphenazine/pharmacology , Image Processing, Computer-Assisted , Male , Olanzapine , Prosencephalon/metabolism , Rats , Rats, Sprague-Dawley , Receptors, Dopamine/metabolism
19.
Bioorg Med Chem ; 14(6): 1918-23, 2006 Mar 15.
Article in English | MEDLINE | ID: mdl-16290940

ABSTRACT

We investigated acid-catalyzed rearrangement of thebaine 14 and its N-propyl analog 15 with methanesulfonic acid in the presence of the nucleophiles methanethiol and hydrogen sulfide. R(-)-2-methylthioapocodeine 16, R(-)-2-methylthioapomorphine 18, and their N-n-propyl analogs 17, 19 were obtained by rearrangement in the presence of methanethiol. However, with hydrogen sulfide, rearrangement of thebaine 14 and its N-n-propyl analog 15 produced sulfide-linked bis-aporphines 21-24 instead of expected R(-)-2-mercaptoapocodeines 12, 13 and R(-)-2-mercaptoapomorphines 10, 11. R(-)-2-Methylthio-N-n-propylnorapomorphine 19 had higher affinity (Ki = 3.7 nM) at D2 receptors in rat forebrain tissue than other novel 2-substituted sulfur-containing aporphines (Ki > or = 50 nM). Behavioral testing of the novel agents in rat indicated moderate locomotor arousal after systemic injection, and none after intragastric administration, indicating poor oral bioavailability.


Subject(s)
Aporphines/chemistry , Aporphines/chemical synthesis , Receptors, Dopamine/metabolism , Sulfur/chemistry , Animals , Aporphines/pharmacology , Brain/drug effects , Brain/metabolism , Brain/physiology , Drug Evaluation, Preclinical , Male , Molecular Structure , Motor Activity/drug effects , Rats , Sulfur/pharmacology
20.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 23(6): 1237-40, 2006 Dec.
Article in Chinese | MEDLINE | ID: mdl-17228716

ABSTRACT

The purpose of this article is to evaluate the role of quantitative margin features in the computer-aided diagnosis of malignant and benign solid breast masses using sonographic imaging. The tumour was seperated by the expert. Three contour features circurity (C), area ratio (A) and length width ratio (LWR) was caculated from the tumour contour. Then back-propagation (BP) neural network with contour features was used to classify tumors into benign and malignant. Results from 119 ultrasonic images have been applied in this experiment. BP neural network yielded the following results: 89.7% and 73.5% respectively. The methods applied in this paper are helpful to raise the correctance of breast cancer diagnosis.


Subject(s)
Breast Neoplasms/diagnostic imaging , Image Processing, Computer-Assisted/methods , Neural Networks, Computer , Breast Neoplasms/pathology , Female , Humans , Ultrasonography
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