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1.
Psychogeriatrics ; 24(4): 830-837, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38692585

ABSTRACT

BACKGROUND: Drivers with dementia are at a higher risk of motor vehicle accidents. The characteristics of driving behaviour of patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD) have not been fully elucidated. We investigated driving ability and its relationship with cognitive function and magnetic resonance imaging (MRI) morphometry indicators. METHODS: The driving abilities of 19 patients with AD and 11 with amnestic MCI (aMCI) were evaluated using a driving simulator. The association between each driving ability parameter and the Mini-Mental State Examination (MMSE) score or voxel-based specific regional analysis system for AD (VSRAD) was assessed. RESULTS: Patients with AD made a significantly higher number of operational errors than those with aMCI in attention allocation in the complex task test (P = 0.0008). The number of operational errors in attention allocation in the complex task test significantly and negatively correlated with MMSE scores in all participants (r = -0.4354, P = 0.0162). The decision time in the selective reaction test significantly and positively correlated with the severity and extent of medial temporal structural atrophy (r = 0.4807, P = 0.0372; r = 0.4862, P = 0.0348; respectively). CONCLUSION: An increase in the operational errors for attention allocation in the complex task test could be a potential indicator of progression from aMCI to AD. Atrophy of the medial temporal structures could be a potential predictor of impaired judgement in driving performance in aMCI and AD. A driving simulator could be useful for evaluating the driving abilities of individuals with aMCI and AD.


Subject(s)
Alzheimer Disease , Automobile Driving , Cognitive Dysfunction , Magnetic Resonance Imaging , Neuropsychological Tests , Humans , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/pathology , Automobile Driving/psychology , Male , Female , Aged , Magnetic Resonance Imaging/methods , Neuropsychological Tests/statistics & numerical data , Aged, 80 and over , Mental Status and Dementia Tests/statistics & numerical data , Amnesia/diagnostic imaging , Attention/physiology , Atrophy/pathology
2.
Neuroreport ; 34(5): 267-272, 2023 03 22.
Article in English | MEDLINE | ID: mdl-36881749

ABSTRACT

Strokes can cause a variety of sequelae, such as paralysis, particularly in the early stages after stroke onset. Rehabilitation therapy atthis time often provides some degree of paralysis recovery. Neuroplasticity in the peri-infarcted cerebral cortex induced by exercise training may contribute to recovery of paralysis after cerebral infarction. However, the molecular mechanism of this process remains unclear. This study focused on brain protein kinase C (PKC), which is speculated to be involved in neuroplasticity. We evaluated the functional recovery of cerebral infarction model rats, by using rotarod test after running wheel training and with/without administration of bryostatin, a PKC activator. In addition, the expression of phosphorylated and unphosphorylated PKC subtypes, glycogen synthase kinase 3ß (GSK3ß), and collapsin response-mediator proteins 2 (CRMP2) were analyzed by Western blotting. In the rotarod test, bryostatin administration alone had no effect on gait duration, but the combination of training and this drug significantly prolonged gait duration compared with training alone. In protein expression analysis, the combination of training and bryostatin significantly increased phosphorylation of PKCα and PKCε isoforms, increased phosphorylation of GSK3ß, which acts downstream of PKC, and decreased phosphorylation of CRMP2. The effect of bryostatin in combination with training appears to be mediated via PKC phosphorylation, with effects on functional recovery occurring through the downstream regulation of GSK3ß and CRMP2 phosphorylation.


Subject(s)
Bryostatins , Cerebral Infarction , Physical Conditioning, Animal , Protein Processing, Post-Translational , Stroke , Animals , Rats , Bryostatins/pharmacology , Cerebral Cortex , Glycogen Synthase Kinase 3 beta , Protein Kinase C
3.
J Infect Chemother ; 29(1): 95-97, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36113848

ABSTRACT

Healthcare-associated COVID-19 among vulnerable patients leads to disproportionate morbidity and mortality. Early pharmacologic intervention may reduce negative sequelae and improve survival in such settings. This study aimed to describe outcome of patients with healthcare-associated COVID-19 who received early short-course remdesivir therapy. We reviewed the characteristics and outcome of hospitalized patients who developed COVID-19 during an outbreak that involved two wards at a non-acute care hospital in Japan and received short-course remdesivir. Forty-nine patients were diagnosed with COVID-19, 34 on a comprehensive inpatient rehabilitation ward and 15 on a combined palliative care and internal medicine ward. Forty-seven were symptomatic and 46 of them received remdesivir. The median age was 75, and the median Charlson comorbidity index was 6 among those who received it. Forty-one patients had received one or two doses of mRNA vaccines, while none had received a third dose. Most patients received 3 days of remdesivir. Of the patients followed up to 14 and 28 days from onset, 41/44 (95.3%) and 35/41(85.4%) were alive, respectively. Six deaths occurred by 28 days in the palliative care/internal medicine ward and two of them were possibly related to COVID-19. Among those who survived, the performance status was unchanged between the time of onset and at 28 days.


Subject(s)
COVID-19 Drug Treatment , Humans , Aged , SARS-CoV-2 , Antiviral Agents , Alanine/therapeutic use , Alanine/adverse effects , Delivery of Health Care , Hospitals
4.
Front Aging Neurosci ; 12: 216, 2020.
Article in English | MEDLINE | ID: mdl-32765252

ABSTRACT

OBJECTIVES: Clinical characteristics of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) include migraine, recurrent stroke, white matter lesions, and vascular dementia. CADASIL is one of the most common hereditary cerebral small vessel diseases. Clinical presentation of CADASIL varies and a racial gap may exist between the Asian and Caucasian populations. This is the first nationwide epidemiological survey which aimed to elucidate the clinical features of CADASIL in Japan. Moreover, the registration database of CADASIL was constructed. METHODS: Subjects included CADASIL patients who visited the hospitals (totally 1,448 hospitals) certified by the Japanese Society of Neurology and/or Japan Stroke Society in 2016. This study consisted of a two-step survey; patients with CADASIL were identified genetically by the first questionnaire, and their clinical features were assessed by the second questionnaire. Selected 6 hospitals registered the data of all CADASIL patients using a Research Electronic Data Capture (REDCap) system for the second questionnaire. RESULTS: Based on the criteria, 88 patients (50 male and 38 female) with CADASIL were enrolled. The mean age of symptom onset was 49.5 years. Sixteen (18.2%) patients had an elderly onset (>60 years). Thirteen patients (13.6%) had history of migraine with aura and 33 patients (37.5%) had vascular risk factor(s). From among the 86 patients who were examined using magnetic resonance imaging, abnormal deep white matter lesions were detected in 85 patients (98.8%), WMLs extending to anterior temporal pole in 73 patients (84.9%), and cerebral microbleeds in 41 patients (47.7%). Anti-platelet therapy was received by 65 patients (73.9%). Thirty-eight patients (43.2%) underwent treatment with lomerizine hydrochloride. Thirty-four different mutations of NOTCH3 were found in exons 2, 3, 4, 5, 6, 8, 11, 14, and 19. Most of the mutations existed in exon 4 (n = 44, 60.3%). The prevalence rate of CADASIL was 1.20 to 3.58 per 100,000 adults in Japan. CONCLUSION: This questionnaire-based study revealed clinical features and treatment status in Japanese CADASIL patient, although it may not be an exhaustive search. We have constructed the REDCap database for these CADASIL patients.

5.
Brain Res ; 1736: 146779, 2020 06 01.
Article in English | MEDLINE | ID: mdl-32171704

ABSTRACT

Inflammation plays an important role in acute and chronic cerebral ischemia. Recent reports indicate that the inflammatory response triggered by tissue damage is mediated by a multiple-protein complex called the inflammasome. The NOD-like receptor family, pyrin domain containing 3 (NLRP3) and absent in melanoma 2 (AIM2) inflammasome complex triggers caspase 1-mediated maturation of interleukin (IL)-1ß and IL-18. This study tested the hypothesis that chronic cerebral hypoperfusion activates inflammasomes in the white matter of the brain. To induce cerebral hypoperfusion, C57BL/6J mice were subjected to a sham or bilateral common carotid artery stenosis (BCAS) operation using microcoils with an internal diameter of 0.18 mm. At 2 and 4 weeks after BCAS, the mice were sacrificed (n = 5 in each group). Coronal sections were stained with anti-NLRP3 and anti-AIM2 antibodies. Activation of the inflammasome and cytokines was assessed using immunohistochemistry and cell counting. IL-18 and IL-1ß levels were determined by ELISA. Cell counting revealed an increase in NLRP3 and AIM2 inflammasomes at 2 and 4 weeks after BCAS. Immunoreactivity was observed in glial cells in the white matter and corpus callosum. IL-18 and IL-1ß concentrations were significantly increased compared with those in the sham operation group. Expression of NLRP3 and AIM2 was upregulated in glial cells in the autopsied brains of patients with cerebral infarction in the chronic phase. These results suggest that chronic cerebral hypoperfusion induces upregulation of NLRP3 and AIM2 inflammasomes; therefore, inflammasomes may play an important role in the sterile inflammatory response in astrocytes and microglia during chronic cerebral hypoperfusion.


Subject(s)
DNA-Binding Proteins/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Reperfusion Injury/metabolism , Animals , Brain/metabolism , Brain Ischemia/metabolism , Caspase 1/metabolism , DNA-Binding Proteins/physiology , Inflammasomes/metabolism , Inflammation , Interleukin-18/metabolism , Interleukin-1beta/metabolism , Male , Mice , Mice, Inbred C57BL , Microglia/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/physiology , Perfusion/methods , Reperfusion Injury/physiopathology , White Matter/metabolism
6.
Neuroreport ; 31(2): 148-155, 2020 01 27.
Article in English | MEDLINE | ID: mdl-31855901

ABSTRACT

Adiponectin is a plasma protein predominantly derived from adipocytes. Adiponectin has beneficial properties against diabetes, cardiovascular diseases, and cancer. In experimental acute cerebral ischemia, adiponectin accumulates on vessels in ischemic lesions and has anti-inflammatory protective effects. Chronic cerebral hypoperfusion is associated with white matter lesions and risk of dementia. Chronic cerebral hypoperfusion induced by permanent occlusion of the bilateral common carotid artery can experimentally produce cerebrovascular white matter lesions in the rat brain. Microglia are activated shortly after ischemia and correlate with the severity of white matter and hippocampal tissue damage. These data suggest that the inflammatory response selectively increases white matter and hippocampal damage during chronic cerebral hypoperfusion. However, factors protecting the cerebral cortex have not been elucidated. To clarify the role of adiponectin, we investigated possible changes in adiponectin and adiponectin receptor 1 (ADR1) in the brains of rats under chronic cerebral hypoperfusion. Adiponectin accumulated on the vessels predominantly in the cerebral cortex under chronic cerebral hypoperfusion. Adiponectin accumulation was not detected in the white matter or hippocampus. In the cerebral cortex, the number of ADR1-immunopositive vessels was increased, and adiponectin was colocalized with ADR1. It is plausible that accumulation of adiponectin may be mediated by the binding of adiponectin to ADR1, and its accumulation in the cerebral cortex may protect tissue injury by inhibiting inflammation under chronic cerebral hypoperfusion.


Subject(s)
Adiponectin/metabolism , Adiponectin/pharmacology , Brain Ischemia/drug therapy , Microglia/drug effects , Animals , Brain Ischemia/metabolism , Disease Models, Animal , Hippocampus/drug effects , Hippocampus/metabolism , Inflammation/metabolism , Male , Microglia/metabolism , Rats, Wistar , White Matter/drug effects , White Matter/metabolism , White Matter/pathology
7.
Neurosci Lett ; 704: 133-140, 2019 06 21.
Article in English | MEDLINE | ID: mdl-30954605

ABSTRACT

Alzheimer's disease (AD) is the most common type of dementia in aging adults. Increasing evidence has revealed that vascular risk factors influence the midlife development of AD and that diet-induced obesity accelerates tau phosphorylation in tau transgenic mice and increases the level of serum leptin receptor (leptin-R). Leptin-R is upregulated in the peri-infarct cortices after acute cerebral ischemia. Leptin may be protective against the development of AD as it can inactivate GSK-3ß through the phosphorylation of Ser-9, leading to the reduction of tau phosphorylation. Using tau transgenic mice, the present study examined whether chronic cerebral hypoperfusion affects leptin-R signaling and tau phosphorylation. Eight-month-old tau transgenic mice (T44) overexpressing the shortest human tau isoform were subjected to chronic cerebral hypoperfusion with bilateral common carotid artery stenosis (BCAS) using microcoils or sham surgery. Their brains were analyzed four weeks later to evaluate the expression of phosphorylated tau and leptin-R via immunohistochemistry and Western blot analysis. In addition, expression of leptin-R was examined in the rat primary astrocyte cultures subjected to prolonged chemical hypoxic stress, as well as in autopsied brains. BCAS upregulated leptin-R expression and promoted the expression of phosphorylated tau in T44 Tg mice. In primary astrocyte cultures, leptin-R was upregulated under hypoxic conditions via the phosphorylated AKT/pAKT pathway, possibly suppressing the expression of caspase 3. Leptin-R was also strongly expressed in autopsied brains with AD and cerebrovascular diseases. These results collectively indicate that chronic cerebral hypoperfusion promotes leptin-R signaling and tau phosphorylation.


Subject(s)
Astrocytes/metabolism , Brain Ischemia/metabolism , Cerebral Cortex/metabolism , Receptors, Leptin/metabolism , tau Proteins/metabolism , Animals , Brain Ischemia/etiology , Carotid Stenosis/complications , Cerebral Cortex/blood supply , Male , Mice, Transgenic , Phosphorylation , Up-Regulation
8.
Neuroreport ; 29(1): 54-58, 2018 Jan 03.
Article in English | MEDLINE | ID: mdl-29135714

ABSTRACT

It has been suggested that serotonin (5-HT) may be implicated in functional recovery after stroke; however, the underlying molecular mechanisms remain unknown. Here, the role of 5-HT was verified using ritanserin, a potent 5-HT2A receptor antagonist, and protein expression and modification were analyzed to further understand the association between paralysis recovery and molecular mechanisms in the brain. Experimental cerebral cortex infarctions were induced by photothrombosis in rats. Voluntary exercise was initiated 2 days after surgery. Motor performance was then measured using the rotarod test. Differences in protein expression and phosphorylation in the perilesional cortex were analyzed using western blot. In behavioral evaluations, performance in the rotarod test was significantly increased by exercise. However, there was a significantly lower value in time until falling after combined exercise and ritanserin administration compared with that of exercise alone. Protein expression analysis revealed that phosphorylation of protein kinase C (PKC) α, PKCε, and growth-associated protein 43 (GAP43) was significantly upregulated by exercise. These effects were attenuated by ritanserin administration. These data suggest that 5-HT may be related to the underlying mechanisms of exercise-dependent paralysis recovery, that is, exercise-dependent plasticity through the phosphorylation of PKC and GAP43.


Subject(s)
Cerebral Infarction/complications , Cerebral Infarction/drug therapy , Recovery of Function/drug effects , Ritanserin/therapeutic use , Serotonin Antagonists/therapeutic use , Animals , Cerebral Infarction/rehabilitation , Disease Models, Animal , GAP-43 Protein/metabolism , Gene Expression Regulation/drug effects , Locomotion/drug effects , Male , Motor Activity/drug effects , Physical Conditioning, Animal/methods , Protein Kinase C/metabolism , Rats , Rats, Sprague-Dawley
9.
Neuroreport ; 27(9): 659-64, 2016 06 15.
Article in English | MEDLINE | ID: mdl-27128726

ABSTRACT

Although it has been suggested that the combination of exercise and bryostatin-1 administration may induce greater functional recovery than exercise alone, the detailed molecular mechanisms are not well known. Here, we examined the relationship between this combination treatment and monoamine dynamics in the cerebral cortex peri-infarction area to promote our understanding of these molecular mechanisms. Experimental cerebral cortex infarctions were produced by photothrombosis in rats. Voluntary exercise was initiated 2 days after surgery. Motor performance was then measured using the rotarod test. Monoamine concentrations in the perilesional cortex were analyzed by high-performance liquid chromatography. In behavioral evaluations, performance in the rotarod test was significantly increased by exercise. Moreover, performance in the rotarod test after the combination of exercise and bryostatin-1 administration was significantly greater than that after exercise alone. In the analysis of monoamines, serotonin (5-HT) concentrations were significantly higher in the groups treated with exercise and bryostatin-1. In addition, 5-HT turnover was significantly lower in the groups treated with exercise and bryostatin-1. Furthermore, the mean latency in the rotarod test showed a significant positive correlation with 5-HT levels. In immunohistochemical analysis, 5-HT immunoreactivity in the dorsal raphe nucleus was shown to be higher in the groups treated with exercise. In the present study, we detected changes in the levels of monoamines associated with the combined treatment of exercise and bryostatin-1 administration in the perilesional cortex. It has been suggested that this combination of therapies may affect 5-HT turnover and serve to increase local 5-HT concentrations in the perilesional area.


Subject(s)
Adjuvants, Immunologic/therapeutic use , Bryostatins/therapeutic use , Cerebral Infarction/drug therapy , Cerebral Infarction/rehabilitation , Exercise Therapy/methods , Serotonin/metabolism , Animals , Biogenic Monoamines/metabolism , Cerebral Cortex/metabolism , Disease Models, Animal , Male , Motor Activity/drug effects , Rats , Rats, Sprague-Dawley , Reaction Time/drug effects , Recovery of Function/drug effects , Recovery of Function/physiology , Rotarod Performance Test
10.
J Neurochem ; 135(5): 943-57, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26375300

ABSTRACT

Thirteen-lined ground squirrels (Ictidomys tridecemlineatus) have an extraordinary capacity to withstand prolonged and profound reductions in blood flow and oxygen delivery to the brain without incurring any cellular damage. As such, the hibernation torpor of I. tridecemlineatus provides a valuable model of tolerance to ischemic stress. Herein, we report that during hibernation torpor, a marked reduction in the phosphorylation of the ribosomal protein S6 (rpS6) occurs within the brains of I. tridecemlineatus. Of note, rpS6 phosphorylation was shown to increase in the brains of rats that underwent an occlusion of the middle cerebral artery. However, such an increase was attenuated after the implementation of an ischemic preconditioning paradigm. In addition, cultured cortical neurons treated with the rpS6 kinase (S6K) inhibitors, D-glucosamine or PF4708671, displayed a decrease in rpS6 phosphorylation and a subsequent increase in tolerance to oxygen/glucose deprivation, an in vitro model of ischemic stroke. Collectively, such evidence suggests that the down-regulation of rpS6 signal transduction may account for a substantial part of the observed increase in cellular tolerance to brain ischemia that occurs during hibernation torpor and after ischemic preconditioning. Further identification and characterization of the mechanisms used by hibernating species to increase ischemic tolerance may eventually clarify how the loss of homeostatic control that occurs during and after cerebral ischemia in the clinic can ultimately be minimized and/or prevented. Mammalian hibernation provides a valuable model of tolerance to ischemic stress. Herein, we demonstrate that marked reductions in the phosphorylation of ribosomal protein S6 (rpS6), extracellular signal-regulated kinase family of mitogen-activated protein (MAP) kinase p44/42 (p44/42MAPK) and ribosomal protein S6 kinase (S6K) occur within the brains of both hibernating squirrels and rats, which have undergone an ischemic preconditioning paradigm. We therefore propose that the down-regulation of rpS6 signal transduction may account for a substantial part of the observed increase in cellular tolerance to brain ischemia that occurs during hibernation torpor and after ischemic preconditioning, via a suppression of protein synthesis and/or energy consumption.


Subject(s)
Gene Expression Regulation/physiology , Hibernation , Infarction, Middle Cerebral Artery/prevention & control , Ischemic Preconditioning , Ribosomal Protein S6/metabolism , Animals , Cells, Cultured , Cerebral Cortex , Disease Models, Animal , Extracellular Signal-Regulated MAP Kinases/metabolism , Gene Expression Regulation/genetics , Glucose/deficiency , Male , Molecular Sequence Data , Neurons/metabolism , Neurons/pathology , Oxygen/metabolism , Phosphorylation , Rats , Rats, Sprague-Dawley , Ribosomal Protein S6/genetics , Sciuridae , Signal Transduction/genetics , Signal Transduction/physiology , Time Factors
11.
Am J Phys Med Rehabil ; 94(3): 239-43, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25299527

ABSTRACT

Recently, it has become widely known that neuronal reorganization in the perilesional cortex contributes to some improvement of hemiparesis after stroke. Here, the authors examined in vivo the effects of administration of bryostatin-1, an activator of protein kinase C, combined with voluntary exercise on functional recovery and on cortical phosphorylation of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor subunit GluR1 after infarction.In behavioral evaluation, the mean latency until falling from a rotating rod in the group with exercise and administered agent at 8 days after infarction was significantly longer than that in the other groups. Although there were no significant changes in GluR1 phosphorylation between bryostatin-1 administration alone and the untreated groups, exercise induced an increase in phosphorylated-Ser845-GluR1. Moreover, combining exercise with administration led to increased phosphorylated-Ser831-GluR1.These results suggest that bryostatin-1 facilitated exercise-induced paralysis recovery, which is possibly mediated by synaptic plasticity related to an increase in synaptic transmission efficiency.


Subject(s)
Bryostatins/therapeutic use , Cerebral Infarction/therapy , Physical Conditioning, Animal , Protein Kinase C/metabolism , Animals , Blotting, Western , Combined Modality Therapy , Enzyme Activation , Male , Phosphorylation , Rats, Sprague-Dawley , Receptors, AMPA/metabolism
12.
Neurol Sci ; 35(1): 53-9, 2014 Jan.
Article in English | MEDLINE | ID: mdl-23793170

ABSTRACT

Recently, it has become widely known that rehabilitative training after stroke brings about some improvement of paralysis and disability; however, not much is known about the relationship between paralysis recovery and the participation of plasticity-related molecules. Hence, the localization and level of expression of several proteins in the cerebral cortex of rat groups with/without voluntary exercise using a running wheel after photo thrombotic infarction were examined in this study. In behavioral evaluation, the mean latency until falling from a rotating rod in the group with voluntary exercise at 6 days after infarction was significantly longer than that in the group without exercise. Immunohistochemical localization of c-Fos protein after behavioral test occurred in the area surrounding the infarction core in the exercise group. In protein expression analysis, protein kinase C (PKC), growth-associated protein 43 (GAP43) and phosphorylated at serine 41 GAP43 (p-GAP43) were significantly increased after voluntary exercise compared with those in rats without exercise. Expression of PKC immunoreactivity was observed in layer III of the perilesional cortex in rats with exercise, and the intracellular localization in the pyramidal neurons was mainly translocated to the plasma membrane. The expression and localization of these proteins may be related to the underlying mechanisms of exercise-induced paralysis recovery, that is, neuronal plasticity and remodeling of cortical connections through the phosphorylation of GAP43 by interaction with PKC. In the present study, the participation of at least some of the modulators associated with the improvement of motor deficit adjacent to the brain lesion might have been detected.


Subject(s)
Cerebral Infarction/enzymology , Cerebral Infarction/rehabilitation , Physical Conditioning, Animal , Protein Kinase C/metabolism , Recovery of Function/physiology , Animals , Blotting, Western , Cerebral Cortex/enzymology , Immunohistochemistry , Male , Rats , Rats, Sprague-Dawley
15.
Tissue Eng Part A ; 19(1-2): 24-9, 2013 Jan.
Article in English | MEDLINE | ID: mdl-22839964

ABSTRACT

Regenerative therapy using stem cells is a promising approach for the treatment of stroke. Recently, we reported that dental pulp stem cells (DPSC) ameliorated ischemic tissue injury in the rat brain and accelerated functional recovery after middle cerebral artery occlusion (MCAO). In this study, we investigated the effects of stem cells from human exfoliated deciduous tooth (SHED)-derived conditioned medium (SHED-CM) on permanent MCAO (pMCAO). Adult male Sprague-Dawley rats were subjected to pMCAO. SHED-CM were then administered intranasally, and the motor function and infarct volume were evaluated. Neurogenesis and vasculogenesis were determined using immunochemical markers. The SHED-CM group had more positive signals than the Dulbecco's modified Eagle's medium group, with doublecortin (DCX), neurofilament H, neuronal nuclei, and rat endothelial cell antigen observed in the peri-infarct area. Migration of neuronal progenitor cells (NPC) with DCX from the subventricular zone to the peri-infarct area was observed on days 6 and 16, with migration on day 6 being the most prominent. In conclusion, SHED-CM promoted the migration and differentiation of endogenous NPC, induced vasculogenesis, and ameliorated ischemic brain injury after pMCAO as well as transplantation of DPSC.


Subject(s)
Brain Ischemia/pathology , Brain Ischemia/surgery , Stem Cell Transplantation/methods , Tooth, Deciduous/cytology , Tooth, Deciduous/transplantation , Animals , Doublecortin Protein , Humans , Male , Rats , Rats, Sprague-Dawley , Recovery of Function , Treatment Outcome
16.
Neurosci Lett ; 499(2): 80-3, 2011 Jul 20.
Article in English | MEDLINE | ID: mdl-21640789

ABSTRACT

It has long been debated whether watershed infarcts are caused by hemodynamic or embolic mechanisms. In the present study, we investigated microembolic roles in the pathogenesis of watershed infarcts by examining MRI in a macaque monkey model of multiple microinfarcts. 50 µm microbeads were injected into each internal carotid artery twice with a month interval. Monkeys (n=4) injected with 2250-2800 microbeads per unilateral side showed both cortical and internal watershed infarcts in the acute phase and atrophic changes with microbleeds in the chronic phase. These results suggest embolic pathogenesis can contribute to the genesis of both cortical and internal watershed infarcts in primates.


Subject(s)
Cerebral Infarction/pathology , Disease Models, Animal , Intracranial Embolism/pathology , Microcirculation , Acute Disease , Animals , Chronic Disease , Macaca fascicularis , Magnetic Resonance Imaging/methods , Male
17.
Tissue Eng Part A ; 17(9-10): 1303-11, 2011 May.
Article in English | MEDLINE | ID: mdl-21226624

ABSTRACT

Regenerative therapy using stem cells is a promising approach for the treatment of stroke. Recently, we reported that CD31⁻/CD146⁻ side population (SP) cells from porcine dental pulp exhibit highly vasculogenic potential in hindlimb ischemia. In this study, we investigated the influence of CD31⁻/CD146⁻ SP cells after transient middle cerebral artery occlusion (TMCAO). Adult male Sprague-Dawley rats were subjected to 2 h of TMCAO. Twenty-four hours after TMCAO, CD31⁻/CD146⁻ SP cells were transplanted into the brain. Motor function and infarct volume were evaluated. Neurogenesis and vasculogenesis were determined with immunochemical markers, and the levels of neurotrophic factors were assayed with real-time reverse transcription-polymerase chain reaction. In the cell transplantation group, the number of doublecortin-positive cells increased twofold, and the number of NeuN-positive cells increased eightfold, as compared with the control phosphate-buffered saline group. The vascular endothelial growth factor level in the ischemic brain with transplanted cells was 28 times higher than that in the normal brain. In conclusion, CD31⁻/CD146⁻ SP cells promoted migration and differentiation of the endogenous neuronal progenitor cells and induced vasculogenesis, and ameliorated ischemic brain injury after TMCAO.


Subject(s)
Brain Ischemia/therapy , CD146 Antigen , Dental Pulp , Platelet Endothelial Cell Adhesion Molecule-1 , Stem Cell Transplantation , Stem Cells , Animals , Brain Ischemia/metabolism , Brain Ischemia/pathology , Dental Pulp/cytology , Dental Pulp/metabolism , Doublecortin Protein , Male , Rats , Stem Cells/cytology , Stem Cells/metabolism , Transplantation, Homologous
18.
Biochem Biophys Res Commun ; 402(1): 54-8, 2010 Nov 05.
Article in English | MEDLINE | ID: mdl-20888320

ABSTRACT

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is caused by mutations in human NOTCH3. We have recently reported that mutant Notch3 shows a greater propensity to form aggregates, and these aggregates resist degradation, leading to accumulation in the endoplasmic reticulum (ER). In this study, we searched for low-molecular compounds that decrease the amount of mutant Notch3 aggregates. Using a cell-based system, we found that degradation of preformed mutant aggregates was enhanced by treatment with either 4,5-dianilinophthalimide (DAPH) or staurosporine aglycone (SA), both of which inhibit amyloid ß (Aß) fibrillization. Regarding other low-molecular compounds interacting with Aß fibrils, thioflavin T (ThT) also enhanced the clearance of mutant Notch3. These findings suggest that DAPH, SA, and ThT are potent reagents to dissociate the preformed aggregates of mutant Notch3 by disruption of intermolecular contacts of misfolded proteins. Our study may provide the basis for the development of a pharmacological therapy for CADASIL.


Subject(s)
Amyloid beta-Peptides/antagonists & inhibitors , Amyloid/antagonists & inhibitors , CADASIL/metabolism , Carbazoles/pharmacology , Indole Alkaloids/pharmacology , Phthalimides/pharmacology , Receptors, Notch/metabolism , Amyloid/metabolism , Amyloid beta-Peptides/metabolism , CADASIL/genetics , Cell Line , Humans , Mutation , Receptor, Notch3 , Receptors, Notch/genetics
19.
J Biol Chem ; 285(49): 38382-8, 2010 Dec 03.
Article in English | MEDLINE | ID: mdl-20889503

ABSTRACT

Apolipoprotein E (apoE) ε4 and hyperhomocysteinemia are risk factors for Alzheimer disease (AD). The dimerization of apoE3 by disulfide bonds between cysteine residues enhances apoE3 function to generate HDL. Because homocysteine (Hcy) harbors a thiol group, we examined whether Hcy interferes with the dimerization of apoE3 and thereby impairs apoE3 function. We found that Hcy inhibits the dimerization of apoE3 and reduces apoE3-mediated HDL generation to a level similar to that by apoE4, whereas Hcy does not affect apoE4 function. Western blot analysis of cerebrospinal fluid showed that the ratio of apoE3 dimers was significantly lower in the samples from the patients with hyperhomocysteinemia than in those that from control subjects. Hyperhomocysteinemia induced by subcutaneous injection of Hcy to apoE3 knock-in mice decreased the level of the apoE3 dimer in the brain homogenate. Because apoE-HDL plays a role in amyloid ß-protein clearance, these results suggest that two different risk factors, apoE4 and hyperhomocysteinemia, may share a common mechanism that accelerates the pathogenesis of AD in terms of reduced HDL generation.


Subject(s)
Alzheimer Disease/cerebrospinal fluid , Apolipoprotein E3/cerebrospinal fluid , Homocysteine/cerebrospinal fluid , Protein Multimerization , Alzheimer Disease/genetics , Amyloid beta-Peptides/genetics , Amyloid beta-Peptides/metabolism , Animals , Apolipoprotein E3/genetics , Apolipoprotein E4/cerebrospinal fluid , Apolipoprotein E4/genetics , Brain/metabolism , Disulfides/cerebrospinal fluid , Homocysteine/genetics , Humans , Hyperhomocysteinemia/cerebrospinal fluid , Hyperhomocysteinemia/chemically induced , Hyperhomocysteinemia/genetics , Lipoproteins, HDL/genetics , Lipoproteins, HDL/metabolism , Mice , Mice, Knockout , Risk Factors
20.
Contrast Media Mol Imaging ; 5(2): 70-7, 2010.
Article in English | MEDLINE | ID: mdl-20235150

ABSTRACT

Generally angiogenic factors induce the expression of E-selectin in vascular endothelial cells in the tumors. In this study, we employed an anti-E-selectin monoclonal antibody to target tumors in vivo and evaluated an optical imaging reagent to visualize tumor regions. The anti-E-selectin antibody was conjugated on the surface of liposomes, which encapsulated the near-infrared fluorescent substances Cy3 or Cy5.5. The liposomes efficiently recognized human umbilical vein endothelial cells only when E-selectin was induced by angiogenic factors such as TNF-alpha in vitro. Cy5.5 encapsulated into liposomes that were conjugated with an anti-E-selectin antibody successfully visualized Ehrlich ascites tumor cells when transplanted into mice. Thus, E-selectin targeting with liposomes containing a near-infrared fluorescent dye was found effective in visualizing tumors in vivo. This strategy should be extremely useful as a method to identify sentinel lymphatic nodes and angiogenic tumors as well as use for drug delivery to tumor cells.


Subject(s)
Antibodies, Monoclonal , E-Selectin/immunology , Immunoconjugates , Neoplasms/diagnosis , Animals , Carcinoma, Ehrlich Tumor/diagnosis , Endothelial Cells/cytology , Endothelium, Vascular , Humans , Liposomes , Mice , Neoplasms/pathology , Neovascularization, Pathologic/diagnosis , Umbilical Veins
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