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1.
J Cell Commun Signal ; 18(1): e12019, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38545253

ABSTRACT

Lysophosphatidic acid (LPA) and sphingosine 1-phosphate (S1P) are bioactive phospholipids that act as mitogens in various cancers. Both LPA and S1P activate G-protein coupled receptors (GPCRs). We examined the role of CCN1/CYR61, an inducible matricellular protein, in LPA-induced signal transduction in PC-3 human prostate cancer cells. We found that both LPA and S1P induced expression of CCN1 and CCN2 within 2-4 h. CCN1 was induced by 18:1-LPA, but not by 18:0-, 18:2-, or 18:3-LPAs. A free fatty acid receptor-4 agonist inhibited LPA-induced CCN1 induction. CCN1 appeared in the ECM within 2 h after LPA addition. LPA caused biphasic activation of Erk MAPK, with an initial peak at 10-20 min followed by a later phase after 6 h. LPA increased adhesion of PC-3 cells to culture substrates (standard culture plates, fibronectin, or extracellular matrix) at 2 h, an intermediate event between early and late LPA signals. Knockdown of CCN1 suppressed LPA-induced adhesion to ECM or fibronectin. ECM from CCN1 knockdown cells was a poor substrate for adhesion, as compared to ECM from control cells. These results suggest that CCN1 contributes to LPA responses in the tumor microenvironment. The LPA-CCN1 axis holds promise for the development of novel therapeutic strategies in cancer.

2.
Matrix Biol ; 89: 27-42, 2020 07.
Article in English | MEDLINE | ID: mdl-32001344

ABSTRACT

Versican is a large extracellular matrix (ECM) chondroitin sulfate (CS) proteoglycan found in most soft tissues, which is encoded by the VCAN gene. At least four major isoforms (V0, V1, V2, and V3) are generated via alternative splicing. The isoforms of versican are expressed and accumulate in various tissues during development and disease, where they contribute to ECM structure, cell growth and migration, and immune regulation, among their many functions. While several studies have identified the mRNA transcript for the V3 isoform in a number of tissues, little is known about the synthesis, secretion, and targeting of the V3 protein. In this study, we used lentiviral generation of doxycycline-inducible rat V3 with a C-terminal tag in stable NIH 3T3 cell lines and demonstrated that V3 is processed through the classical secretory pathway. We further show that N-linked glycosylation is required for efficient secretion and solubility of the protein. By site-directed mutagenesis, we identified amino acids 57 and 330 as the active N-linked glycosylation sites on V3 when expressed in this cell type. Furthermore, exon deletion constructs of V3 revealed that exons 11-13, which code for portions of the carboxy region of the protein (G3 domain), are essential for V3 processing and secretion. Once secreted, the V3 protein associates with hyaluronan along the cell surface and within the surrounding ECM. These results establish critical parameters for the processing, solubility, and targeting of the V3 isoform by mammalian cells and establishes a role for V3 in the organization of hyaluronan.


Subject(s)
Versicans/chemistry , Versicans/metabolism , Alternative Splicing , Animals , Exons , Glycosylation , HEK293 Cells , Humans , Mice , Mutagenesis, Site-Directed , NIH 3T3 Cells , Protein Domains , Protein Isoforms/chemistry , Protein Isoforms/metabolism , Rats , Versicans/genetics
3.
J Child Sex Abus ; 28(2): 240-258, 2019.
Article in English | MEDLINE | ID: mdl-30307798

ABSTRACT

The present study looked at child sexual abuse (CSA) from the perpetrator's perspective, focusing on precursors to, sustaining mechanisms, and inhibitors of CSA. Individuals serving sentences for sexual abuse of children under the age of 16 were interviewed (N = 8). A qualitative design using interpretative phenomenological analysis was employed. Negative childhood events such as poly-victimization, poor social skills, loneliness, and insecure sexual identity were reported as predisposing elements. Abuse was sustained due to a strong conviction of not being responsible for doing anything wrong. Respondents conveyed few salient inhibitors for the abuse, though not wanting to physically harm the child was often cited as important. Implications for the prevention of CSA in risk groups suggest the need to increase the understanding of children from a child's perspective, changing conceptions leading to disavowal of adult responsibility toward children, strengthening social competency, integration into a social context, and increasing knowledge about the harmful consequences of CSA.


Subject(s)
Child Abuse, Sexual , Criminals/psychology , Adolescent , Adult , Child , Female , Humans , Male , Norway , Prisoners , Qualitative Research
4.
Cancer Manag Res ; 10: 2893-2903, 2018.
Article in English | MEDLINE | ID: mdl-30214284

ABSTRACT

CCN proteins are secreted into the extracellular environment where they interact with both components of the extracellular matrix and with cell surface receptors to regulate cellular function. Through these interactions, CCNs act as extracellular ligands to activate intracellular signal transduction pathways. CCN4/WISP-1, like other CCNs, plays multiple physiologic roles in development and also participates in pathogenesis. CCN4 is of particular interest with respect to cancer, showing promise as a biomarker or prognostic factor as well as a potential therapeutic target. This review focuses on recent work addressing the role of CCN4 in cancer. While CCN4 has been identified as an oncogene in a number of cancers, where it enhances cell migration and promoting epithelial-mesenchymal transition, there are other cancers where CCN4 appears to play an inhibitory role. The mechanisms underlying these differences in cellular response have not yet been delineated, but are an active area of investigation. The expression and activities of CCN4 splice variants are likewise an emerging area for study. CCN4 acts as an autocrine factor that regulates the cancer cells from which it is secreted. However, CCN4 is also a paracrine factor that is secreted by stromal fibroblasts, and can affect the function of vascular endothelial cells. In summary, current evidence is abundant in regard to establishing potential roles for CCN4 in oncogenesis, but much remains to be learned about the functions of this fascinating protein as both an autocrine and paracrine regulator in the tumor microenvironment.

5.
Exp Neurol ; 296: 49-61, 2017 10.
Article in English | MEDLINE | ID: mdl-28684211

ABSTRACT

Dysregulation of axonal bioenergetics is likely a key mechanism in the initiation and progression of age-related neurodegenerative diseases. Glaucoma is a quintessential neurodegenerative disorder characterized by progressive deterioration of the optic nerve (ON) and eventual death of retinal ganglion cells (RGCs). Age and elevation of intraocular pressure are key risk factors in glaucoma, but the common early hallmarks of decreased axonal transport and increased bioenergetic vulnerability likely underlie disease initiation. We examined the correlation between bioenergetics and axonal transport with mitochondrial mutation frequency and post-translational modifications of mitofusin 2 (Mfn2) in RGCs during glaucoma progression. No increase in the frequency of mtDNA mutations was detected, but we observed significant shifts in mitochondrial protein species. Mfn2 is a fusion protein that functions in mitochondrial biogenesis, maintenance, and mitochondrial transport. We demonstrate that Mfn2 accumulates selectively in RGCs during glaucomatous degeneration, that two novel states of Mfn2 exist in retina and ON, and identify a phosphorylated form that selectively accumulates in RGCs, but is absent in ON. Phosphorylation of Mfn2 is correlated with higher ubiquitination, and failure of the protein to reach the ON. Together, these data suggest that post-translational modification of Mfn2 is associated with its dysregulation during a window of metabolic vulnerability that precedes glaucomatous degeneration. Future work to either manipulate expression of Mfn2 or to prevent its degradation could have therapeutic value in the treatment of neurodegenerative diseases where long-tract axons are vulnerable.


Subject(s)
Aging , GTP Phosphohydrolases/metabolism , Gene Expression Regulation/physiology , Glaucoma/pathology , Retinal Ganglion Cells/metabolism , Age Factors , Animals , Disease Models, Animal , Disease Progression , Eye Proteins/genetics , Eye Proteins/metabolism , GTP Phosphohydrolases/genetics , Immunoprecipitation , Membrane Glycoproteins/genetics , Membrane Glycoproteins/metabolism , Mice , Mice, Inbred DBA , Mice, Transgenic , Mutation/genetics , Phosphopyruvate Hydratase/metabolism , Phosphorylation , RNA, Messenger/metabolism , Ubiquitination/genetics
6.
J Biol Chem ; 292(1): 51-63, 2017 Jan 06.
Article in English | MEDLINE | ID: mdl-27895126

ABSTRACT

Viral infection is an exacerbating factor contributing to chronic airway diseases, such as asthma, via mechanisms that are still unclear. Polyinosine-polycytidylic acid (poly(I:C)), a Toll-like receptor 3 (TLR3) agonist used as a mimetic to study viral infection, has been shown to elicit inflammatory responses in lungs and to exacerbate pulmonary allergic reactions in animal models. Previously, we have shown that poly(I:C) stimulates lung fibroblasts to accumulate an extracellular matrix (ECM), enriched in hyaluronan (HA) and its binding partner versican, which promotes monocyte adhesion. In the current study, we aimed to determine the in vivo role of versican in mediating inflammatory responses in poly(I:C)-induced lung inflammation using a tamoxifen-inducible versican-deficient mouse model (Vcan-/- mice). In C57Bl/6 mice, poly(I:C) instillation significantly increased accumulation of versican and HA, especially in the perivascular and peribronchial regions, which were enriched in infiltrating leukocytes. In contrast, versican-deficient (Vcan-/-) lungs did not exhibit increases in versican or HA in these regions and had strikingly reduced numbers of leukocytes in the bronchoalveolar lavage fluid and lower expression of inflammatory chemokines and cytokines. Poly(I:C) stimulation of lung fibroblasts isolated from control mice generated HA-enriched cable structures in the ECM, providing a substrate for monocytic cells in vitro, whereas lung fibroblasts from Vcan-/- mice did not. Moreover, increases in proinflammatory cytokine expression were also greatly attenuated in the Vcan-/- lung fibroblasts. These findings provide strong evidence that versican is a critical inflammatory mediator during poly(I:C)-induced acute lung injury and, in association with HA, generates an ECM that promotes leukocyte infiltration and adhesion.


Subject(s)
Chemokines/metabolism , Cytokines/metabolism , Interferon Inducers/toxicity , Pneumonia/prevention & control , Poly I-C/toxicity , Versicans/physiology , Animals , Bronchoalveolar Lavage Fluid/chemistry , Cells, Cultured , Female , Fibroblasts/cytology , Fibroblasts/drug effects , Fibroblasts/metabolism , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Monocytes/cytology , Monocytes/drug effects , Monocytes/metabolism , Pneumonia/chemically induced , Pneumonia/metabolism , Pneumonia/pathology
7.
BMC Psychiatry ; 13: 13, 2013 Jan 08.
Article in English | MEDLINE | ID: mdl-23297686

ABSTRACT

BACKGROUND: This study will explore the validity of psychiatric diagnoses in administrative registers with special emphasis on comorbid anxiety and substance use disorders. METHODS: All new patients admitted to psychiatric hospital in northern Norway during one year were asked to participate. Of 477 patients found eligible, 272 gave their informed consent. 250 patients (52%) with hospital diagnoses comprised the study sample. Expert diagnoses were given on the basis of a structured diagnostic interview (M.I.N.I.PLUS) together with retrospective checking of the records. The hospital diagnoses were blind to the expert. The agreement between the expert's and the clinicians' diagnoses was estimated using Cohen's kappa statistics. RESULTS: The expert gave a mean of 3.4 diagnoses per patient, the clinicians gave 1.4. The agreement ranged from poor to good (schizophrenia). For anxiety disorders (F40-41) the agreement is poor (kappa = 0.12). While the expert gave an anxiety disorder diagnosis to 122 patients, the clinicians only gave it to 17. The agreement is fair concerning substance use disorders (F10-19) (kappa = 0.27). Only two out of 76 patients with concurrent anxiety and substance use disorders were identified by the clinicians. CONCLUSIONS: The validity of administrative registers in psychiatry seems dubious for research purposes and even for administrative and clinical purposes. The diagnostic process in the clinic should be more structured and treatment guidelines should include comorbidity.


Subject(s)
Hospitals, Psychiatric/statistics & numerical data , Mental Disorders/epidemiology , Registries/standards , Adult , Anxiety Disorders/diagnosis , Anxiety Disorders/epidemiology , Comorbidity , Female , Humans , Interview, Psychological , Male , Mental Disorders/diagnosis , Middle Aged , Norway/epidemiology , Registries/statistics & numerical data , Reproducibility of Results , Schizophrenia/diagnosis , Schizophrenia/epidemiology , Substance-Related Disorders/diagnosis , Substance-Related Disorders/epidemiology
8.
BMC Psychiatry ; 12: 13, 2012 Feb 29.
Article in English | MEDLINE | ID: mdl-22373296

ABSTRACT

BACKGROUND: This study has explored the classification of bipolar disorder in psychiatric hospital. A review of the literature reveals that there is a need for studies using stringent methodological approaches. METHODS: 480 first-time admitted patients to psychiatric hospital were found eligible and 271 of these gave written informed consent. The study sample was comprised of 250 patients (52%) with hospital diagnoses. For the study, expert diagnoses were given on the basis of a structured diagnostic interview (M.I.N.I.PLUS) and retrospective review of patient records. RESULTS: Agreement between the expert's and the clinicians' diagnoses was estimated using Cohen's kappa statistics. 76% of the primary diagnoses given by the expert were in the affective spectrum. Agreement concerning these disorders was moderate (kappa ranging from 0.41 to 0.47). Of 58 patients with bipolar disorder, only 17 received this diagnosis in the clinic. Almost all patients with a current manic episode were classified as currently manic by the clinicians. Forty percent diagnosed as bipolar by the expert, received a diagnosis of unipolar depression by the clinician. Fifteen patients (26%) were not given a diagnosis of affective disorder at all. CONCLUSIONS: Our results indicate a considerable misclassification of bipolar disorder in psychiatric hospital, mainly in patients currently depressed. The importance of correctly diagnosing bipolar disorder should be emphasized both for clinical, administrative and research purposes. The findings questions the validity of psychiatric case registers. There are potential benefits in structuring the diagnostic process better in the clinic.


Subject(s)
Bipolar Disorder/classification , Bipolar Disorder/diagnosis , Depressive Disorder/diagnosis , Adolescent , Adult , Aged , Aged, 80 and over , Cohort Studies , Diagnosis, Differential , Female , Hospitalization , Hospitals, Psychiatric , Humans , Male , Middle Aged , Prospective Studies , Reproducibility of Results
9.
Soc Psychiatry Psychiatr Epidemiol ; 47(3): 419-25, 2012 Mar.
Article in English | MEDLINE | ID: mdl-21287142

ABSTRACT

BACKGROUND: The epidemiology of suicidality shows considerable variation across sites. However, one of the strongest predictors of suicide is a suicidal attempt. Knowledge of the epidemiology of suicidal ideas and attempts in the general population as well as in the health care system is of importance for designing preventive strategies. In this study, we will explore the role of the psychiatric hospital in suicide prevention by investigating treated incidence of suicidal ideation and attempt, and further, discern whether sociodemographic, clinical and service utilization factors differ between these two groups at admission. METHODS: The study was a prospective cohort study on treated incidence in a 1-year period and 12-month follow-up. The two psychiatric hospitals in northern Norway, serving a population of about 500,000 people, participated in the study. A total of 676 first-time admissions were retrospectively checked for suicidality at the time of admission. A study sample of 168 patients was found eligible for logistic regression analysis to elucidate the risk profiles of suicidal ideators versus suicidal attempters. GAF, HoNOS and SCL-90-R were used to assess symptomatology at baseline. RESULTS: 52.2% of all patients admitted had suicidal ideas at admission and 19.7% had attempted suicide. In the study sample, there were no differences in risk profile between the two groups with regard to sociodemographic and clinical factors. Males who had made a suicide attempt were less likely to have been in contact with an out-patient clinic before the attempt. The rating scales not measuring suicidality directly showed no differences in symptomatology. CONCLUSION: The findings provide evidence for the importance of the psychiatric hospital in suicide prevention. About half of the admissions were related to suicidality and the similar risk profiles found in suicidal ideators and suicidal attempters indicate that it is the ideators who mostly need treatment that get admitted to the hospital, and should be evaluated and treated with equal concern as those who have attempted suicide.


Subject(s)
Hospitals, Psychiatric , Patient Admission , Suicidal Ideation , Adult , Cohort Studies , Female , Humans , Male , Norway , Prospective Studies
10.
Subst Abuse Treat Prev Policy ; 5: 15, 2010 Jul 07.
Article in English | MEDLINE | ID: mdl-20609222

ABSTRACT

BACKGROUND: Mental distress measured by the HSCL-10 is used as an indicator of psychiatric disorders in population studies, where a higher level of mental distress has been shown to be related to demographic factors such as living conditions and level of education. The first aim of the study was to explore whether mental distress could be a valuable concept in substance use treatment. The second aim of the study was to explore to what degree mental distress among substance users at admission to treatment could be explained by the same demographic factors as in population studies, or whether treatment differences or differences in substance use would be better predictors of mental distress in this population. METHODS: Patients (N = 185) who received inpatient substance use treatment in five different settings in Northern Norway participated in the study. HSCL-10 was used as a measure for mental distress at admission to treatment. The self-report measures AUDIT, DUDIT and DUDIT-E were used for measuring substance use and readiness for treatment. The patients' clinicians reported demographic and treatment factors. A three-block hierarchical multiple regression analysis was conducted to determine potential predictors of mental distress. Block 1 included demographic variables, Block 2 included treatment variables, and Block 3 substance use variables. RESULTS: Patients generally reported a high level of mental distress at admission to treatment, and 83% reported mental distress higher than the established cut-off level. Being female, having previously received psychiatric treatment, having a higher score on DUDIT and AUDIT, and using a larger number of substances all predicted a higher level of mental distress. The model explained 32% of the variance in mental distress. CONCLUSIONS: Mental distress measured by the HSCL-10 can be a valuable concept in substance use treatment. The HSCL-10 can be useful in screening for patients who are in need of further assessment for psychiatric disorders. Female gender, previous psychiatric treatment, and higher use of substances all predicted a higher level of mental distress. The study underlines the importance of assessing the mental health of patients in substance use treatment.


Subject(s)
Inpatients/psychology , Mental Disorders/epidemiology , Substance-Related Disorders/psychology , Substance-Related Disorders/therapy , Adult , Female , Forecasting , Humans , Male , Middle Aged , Norway/epidemiology , Surveys and Questionnaires , Young Adult
11.
Am J Pathol ; 174(6): 2300-9, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19389932

ABSTRACT

Prostaglandin E2 is one of several eicosanoid products of the cyclooxygenase isozymes and is a key regulator of innate immune responses; it also possesses paracrine effects on mature neurons. The prostaglandin E2 receptor family consists of four subtypes of which EP1 and EP2 are known to be expressed by microglia. Lipopolysaccharide (LPS)-induced innate immune activation leads to the degeneration of intermediate progenitor cells (IPCs) that are destined for neuronal maturation in the hippocampal subgranular zone (SGZ); these cells can be identified by the expression of the transcription factor T-box brain gene 2 (Tbr2). Importantly, depletion of LPS-induced IPCs from the SGZ is suppressed by cyclooxygenase inhibitors. We therefore tested the hypothesis that either EP1 or EP2 is critical to LPS-induced depletion of Tbr2+ IPCs from the SGZ. Expression of either EP1 or EP2 was necessary for Toll-like receptor 4-dependent innate immune-mediated depletion of these Tbr2+ IPCs in mice. Moreover, EP1 activation was directly toxic to murine adult hippocampal progenitor cells; EP2 was not expressed by these cells. Finally, EP1 modulated the response of murine primary microglia cultures to LPS but in a manner distinct from EP2. These results indicate that prostaglandin E2 signaling via either EP1 or EP2 is largely to completely necessary for Toll-like receptor 4-dependent depletion of IPCs from the SGZ and suggest further pharmacological strategies to protect this important neurogenic niche.


Subject(s)
Hippocampus/cytology , Neurogenesis/immunology , Receptors, Prostaglandin E/metabolism , Stem Cells/metabolism , Toll-Like Receptor 4/metabolism , Animals , Fluorescent Antibody Technique , Hippocampus/immunology , Hippocampus/metabolism , Immunity, Innate , Lipopolysaccharides/immunology , Mice , Mice, Inbred C57BL , Mice, Mutant Strains , Neurons/immunology , Neurons/metabolism , Receptors, Prostaglandin E, EP1 Subtype , Receptors, Prostaglandin E, EP2 Subtype , Reverse Transcriptase Polymerase Chain Reaction , Stem Cells/cytology , Stem Cells/immunology , T-Box Domain Proteins/biosynthesis , Toll-Like Receptor 4/immunology
12.
Curr Med Chem ; 16(6): 643-51, 2009.
Article in English | MEDLINE | ID: mdl-19199928

ABSTRACT

Alzheimer's disease (AD) is the leading cause of dementia in the elderly. Although the etiology of AD remains unclear, microglia-mediated neuroinflammation is believed to play an important role in its pathogenesis. Microglial activation occurs in AD and is characterized by apparent phagocytic activity and by increased production and secretion of several cytokines, chemokines, reactive oxygen and nitrogen species, prostaglandin (PG)E2, and neurotrophic factors. Microglial activation can be neuroprotective through the release of neurotrophic factors and by phagocytosing Abeta, a critical neurotoxic component in AD brain. Concurrently, microglial activation causes elevated inflammatory responses that lead to paracrine damage to neurons. Therefore, a well-controlled microglial activation that diminishes microglial-mediated oxidative damage while promoting neuronal protection may be the key for AD therapy. Peroxisome proliferator-activated receptor gamma (PPARgamma) has recently gained increasing attention in AD due to its function as a molecular target for non-steroidal anti-inflammatory drugs (NSAIDs). In this review, we will discuss the role of PPARgamma in microglial innate immunity in AD and how pharmacological manipulation of microglial activation using PPARgamma ligands might facilitate the treatment of AD.


Subject(s)
Alzheimer Disease/drug therapy , Alzheimer Disease/immunology , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Microglia/immunology , PPAR gamma/immunology , Alzheimer Disease/pathology , Animals , Humans , Immunity, Innate/drug effects , Immunity, Innate/immunology , Ligands , Microglia/drug effects
13.
BMC Health Serv Res ; 8: 103, 2008 May 14.
Article in English | MEDLINE | ID: mdl-18479506

ABSTRACT

BACKGROUND: Patient satisfaction is an important, but controversial part of health service evaluation. This study dealt with how acknowledgement of illness and treatment needs effected the distribution of positive, neutral and negative evaluations in a group of first time admitted patients to a psychiatric hospital. METHOD: The participants filled out a standardized user satisfaction form before discharge. The number of positive, neutral and negative evaluations for each participant was calculated and used as dependent variables in analyses (Classification Tree) where acknowledgement of illness (The Patients' Experience of Hospitalisation Questionnaire) and treatment needs (HoNOS) were used as explanatory variables in addition to a number of potential confounders. RESULTS: Different constellations of variables explained the three dependent variables. The number of positive scores was a function of age and worry (PEH); neutral scores were explained by HoNOS rated social needs and GAF (functional scale), both at admission. Outcome (GAF functional scale) and age explained the number of negative scores. CONCLUSION: (1) Moderately high negative correlations between positive and neutral scores, and between positive and negative scores, together with a positive correlation between the number of negative and neutral ratings was interpreted to mean that neutral scores sometimes function as undercommunicated negative evaluations. These could better be studied by qualitative methods. (2) The worry subscale (PEH) was important in identifying the majority of patients with the highest numbers of positive scores (patients older than 27.5 yrs with high worry score at admission.). The most dissatisfied group was characterised by denial of both mental problems and need for treatment. (3) Patients with high scores on the HoNOS Social subscale had the highest number of neutral scores. To the extent that neutral evaluations have negative connotations, treatment should focus more effectively on the patients' social needs. (4) The smallest number of negative scores was found among older patients with high functional improvement (GAF F). (5) Increasing age consistently predicted higher satisfaction. A better understanding of why younger patients are more dissatisfied is needed.


Subject(s)
Mental Disorders/therapy , Patient Satisfaction , Psychiatric Department, Hospital , Analysis of Variance , Humans , Inpatients/psychology , Norway , Quality Assurance, Health Care , Residential Treatment , Retrospective Studies
14.
J Neurosci ; 26(11): 3066-76, 2006 Mar 15.
Article in English | MEDLINE | ID: mdl-16540585

ABSTRACT

The deep cerebellar nuclei (DCN) are the main output centers of the cerebellum, but little is known about their development. Using transcription factors as cell type-specific markers, we found that DCN neurons in mice are produced in the rhombic lip and migrate rostrally in a subpial stream to the nuclear transitory zone (NTZ). The rhombic lip-derived cells express transcription factors Pax6, Tbr2, and Tbr1 sequentially as they enter the NTZ. A subset of rhombic lip-derived cells also express reelin, a key regulator of Purkinje cell migrations. In organotypic slice cultures, the rhombic lip was necessary and sufficient to produce cells that migrate in the subpial stream, enter the NTZ, and express Pax6, Tbr2, Tbr1, and reelin. In later stages of development, the subpial stream is replaced by the external granular layer, and the NTZ organizes into distinct DCN nuclei. Tbr1 expression persists to adulthood in a subset of medial DCN projection neurons. In reeler mutant mice, which have a severe cerebellar malformation, rhombic lip-derived cells migrated to the NTZ, despite reelin deficiency. Studies in Tbr1 mutant mice suggested that Tbr1 plays a role in DCN morphogenesis but is not required for reelin expression, glutamatergic differentiation, or the initial formation of efferent axon pathways. Our findings reveal underlying similarities in the transcriptional programs for glutamatergic neuron production in the DCN and the cerebral cortex, and they support a model of cerebellar neurogenesis in which glutamatergic and GABAergic neurons are produced from separate progenitor compartments.


Subject(s)
Cerebellar Nuclei/cytology , Nerve Tissue Proteins/biosynthesis , Rhombencephalon/cytology , Transcription Factors/biosynthesis , Animals , Axonal Transport , Biomarkers , Cell Adhesion Molecules, Neuronal/biosynthesis , Cell Adhesion Molecules, Neuronal/genetics , Cell Lineage , Cell Movement , Cerebellar Nuclei/abnormalities , Cerebellar Nuclei/embryology , DNA-Binding Proteins/biosynthesis , DNA-Binding Proteins/genetics , Efferent Pathways/embryology , Efferent Pathways/physiology , Extracellular Matrix Proteins/biosynthesis , Extracellular Matrix Proteins/genetics , Eye Proteins/biosynthesis , Eye Proteins/genetics , Gestational Age , Glutamic Acid/physiology , Homeodomain Proteins/biosynthesis , Homeodomain Proteins/genetics , Mice , Mice, Inbred C57BL , Mice, Neurologic Mutants , Microscopy, Fluorescence , Morphogenesis , Nerve Tissue Proteins/genetics , Neurons/cytology , Neurons/metabolism , PAX6 Transcription Factor , Paired Box Transcription Factors/biosynthesis , Paired Box Transcription Factors/genetics , Red Nucleus/cytology , Red Nucleus/embryology , Reelin Protein , Repressor Proteins/biosynthesis , Repressor Proteins/genetics , Rhombencephalon/embryology , Rhombencephalon/metabolism , Serine Endopeptidases/biosynthesis , Serine Endopeptidases/genetics , T-Box Domain Proteins/biosynthesis , T-Box Domain Proteins/genetics , Transcription Factors/genetics
15.
FASEB J ; 20(6): 797-9, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16481366

ABSTRACT

Inheritance of APOE alleles is associated with varying clinical outcomes in several neurodegenerative diseases that are associated with innate immune response in brain. We tested the hypothesis that inheritance of different APOE alleles would significantly modulate neurotoxicity arising from glial innate immune response. We first used dissociated cultures of wild-type (wt) murine neurons and glia derived from mice with targeted replacement (TR) of the epsilon2, epsilon3, or, epsilon4 APOE allele. Our results showed that the vast majority of bystander damage to wt neurons derived from microglia was greatest with TR APOE4 glia, intermediate from TR APOE3 glia, and least from TR APOE2 glia and preceded detectable NO secretion. Microglial p38MAPK-dependent cytokine secretion followed a similar pattern of TR APOE dependence. In hippocampal slice cultures, innate immune activation had a similar pattern of TR APOE-dependence and produced postsynaptic neuronal damage in TR APOE4 and TR APOE3 but not TR APOE2 cultures that was p38MAPK dependent. These findings suggest a new mechanism by which inheritance of different APOE alleles may influence the outcome of neurodegenerative diseases associated with microglial innate immune response.


Subject(s)
Alleles , Apolipoproteins E/genetics , Apolipoproteins E/metabolism , Immunity, Innate , Microglia/enzymology , Neurons/pathology , p38 Mitogen-Activated Protein Kinases/metabolism , Animals , Apolipoprotein E4 , Astrocytes , Cells, Cultured , Cytokines/metabolism , Gene Expression Regulation, Enzymologic , Mice , Mice, Transgenic , Neurons/immunology , Signal Transduction
16.
J Biol Chem ; 280(4): 2562-8, 2005 Jan 28.
Article in English | MEDLINE | ID: mdl-15536070

ABSTRACT

The mechanisms that regulate the transition between the initial priming phase and DNA replication in liver regeneration are poorly understood. To study this transition, we compared events occurring after standard two-thirds partial hepatectomy, which elicits full regeneration, with response to a reduced hepatectomy, one-third partial hepatectomy (1/3PH), which leads to little DNA replication. Although the initial response to partial hepatectomy at the priming phase appeared to be similar between the two procedures, cell cycle progression was significantly blunted in 1/3PH mice. Among the main defects observed in 1/3PH mice were an almost complete deficiency in retinoblastoma phosphorylation and the lack of increase in kinase activity associated with cyclin E. We report that, in two-thirds partial hepatectomy mice, the expression of heparin-binding epidermal growth factor-like growth factor (HB-EGF) preceded the start of DNA replication and was not detectable in 1/3PH animals. Injection of HB-EGF into 1/3PH mice resulted in a >15-fold increase in DNA replication. Moreover, we show that hepatocyte DNA replication was delayed in HB-EGF knock-out mice. In summary, we show that HB-EGF is a key factor for hepatocyte progression through G(1)/S transition during liver regeneration.


Subject(s)
Epidermal Growth Factor/metabolism , Heparin/metabolism , Hepatocytes/metabolism , Liver Regeneration , Liver/physiology , Animals , Blotting, Western , Bromodeoxyuridine/pharmacology , Cell Cycle , Cell Proliferation , Cyclin E/metabolism , DNA/metabolism , DNA Replication , G1 Phase , Heparin-binding EGF-like Growth Factor , Hepatocytes/physiology , Immunohistochemistry , Immunoprecipitation , Intercellular Signaling Peptides and Proteins , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Reverse Transcriptase Polymerase Chain Reaction , S Phase , Time Factors
17.
J Neuropathol Exp Neurol ; 63(8): 856-71, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15330340

ABSTRACT

Cerebral palsy is a common birth disorder that frequently involves ischemic-type injury to developing white matter (WM). Dead glial cells are a common feature of this injury and here we describe a novel form of acute ischemic cell death in developing WM astrocytes. Ischemia, modeled by the withdrawal of oxygen and glucose, evoked [Ca2+]i increases and cell death in astrocytes in post-natal day 10 (P10) rat optic nerve (RON). Removing extracellular Ca2+ prevented increases in [Ca2+]i but increased the amount of cell death. Astrocytes showed rapid [Na+]i increases during ischemia and cell death was reduced to control levels by substitution of extracellular Na+ or Cl- or by perfusion with bumetanide, a selective Na-K-Cl cotransport (NKCC) blocker. Astrocytes showed marked swelling during ischemia in the absence of extracellular Ca2+, which was blocked by bumetanide. Raising the extracellular osmolarity to limit water uptake reduced ischemic astrocyte death to control levels. Ultrastructural examination showed that post-ischemic astrocytes had lost their processes and frequently were necrotic, effects partially prevented by bumetanide. At this point in development, therefore, NKCC activation in astrocytes during ischemia produces an osmo-regulatory challenge. Astrocytes can subsequently regulate their cell volume in a Ca2+-dependent fashion but this will require ATP hydrolysis and does not protect the cells against acute cell death.


Subject(s)
Astrocytes/metabolism , Astrocytes/pathology , Brain Ischemia/metabolism , Calcium/metabolism , Nerve Fibers, Myelinated/metabolism , Sodium-Potassium-Chloride Symporters/metabolism , Acute Disease , Animals , Biological Transport, Active , Brain Ischemia/pathology , Calcium/physiology , Calcium Signaling/physiology , Female , In Vitro Techniques , Male , Nerve Fibers, Myelinated/pathology , Rats , Rats, Long-Evans
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