Syoichiro Kono

Cognitive and affective functions in Alzheimer's disease patients with metabolic syndrome

The influence of metabolic syndrome (MetS) on cognitive and affective functions in patients with Alzheimers disease (AD) was examined.

Rivaroxaban and Apixaban Reduce Hemorrhagic Transformation After Thrombolysis by Protection of Neurovascular Unit in Rat

Background and Purpose— This study aimed to assess the risk and benefit of tissue-type plasminogen activator treatment after oral anticoagulation with rivaroxaban or apixaban compared with warfarin or placebo. Methods— Pretreatment with warfarin (0.2 mg/kg per day), rivaroxaban (2 mg/kg per day), apixaban (10 mg/kg per day), or vehicle (0.5% carboxymethyl cellulose sodium salt) was performed for 7 days. Transient middle cerebral artery occlusion was then induced for 120 minutes, followed by reperfusion with tissue-type plasminogen activator (10 mg/kg per 10 mL). Clinical parameters, including cerebral infarction volume, hemorrhagic volume, and blood coagulation, were examined. Twenty-four hours after reperfusion, markers for the neurovascular unit at the peri-ischemic lesion were immunohistochemically examined in brain sections, and matrix metalloproteinase-9 activity was measured by zymography. Results— The paraparesis score was significantly improved in the rivaroxaban-pretreated group compared with the warfarin-pretreated group. Intracerebral hemorrhage was observed in the warfarin-pretreated group, and this was reduced in the rivaroxaban and apixaban-pretreated groups compared with the vehicle group. Marked dissociation of astrocyte foot processes and the basal lamina or pericytes was observed in the warfarin-pretreated group, and this was improved in the rivaroxaban and apixaban-pretreated groups. Furthermore, activation of matrix metalloproteinase-9 in the ipsilateral warfarin-pretreated brain was greatly reduced in rivaroxaban- and apixaban-pretreated rats. Conclusions— This study shows a lower risk of intracerebral hemorrhage after tissue-type plasminogen activator treatment in rats with ischemic stroke that are pretreated with rivaroxaban and apixaban compared with pretreatment with warfarin. Reducing neurovascular dissociation by rivaroxaban and apixaban compared with warfarin could partly explain a reduction in hemorrhagic complications reported in clinical studies.

Intravenous thrombolysis with neuroprotective therapy by edaravone for ischemic stroke patients older than 80 years of age

BACKGROUND Alteplase, a recombinant tissue plasminogen activator (tPA), was approved for patients with acute ischemic stroke within 3 hours of stroke onset in Japan in October 2005 at a dose of 0.6 mg/kg. The aim of this study was to assess the safety and efficacy of alteplase in elderly patients in Japan. METHODS One hundred twenty-nine consecutive patients who were admitted to our 5 hospital groups and who received intravenous tPA within 3 hours of stroke onset between January 2010 and December 2011 were divided into 2 groups by age (<80 years of age [younger group] and >80 years of age [older group]) and by treatment with or without edaravone. Clinical backgrounds and outcomes were investigated. RESULTS The National Institutes of Health Stroke Scale score on admission was not different in both groups, but the National Institutes of Health Stroke Scale scores 7 days after stroke onset were significantly higher in the older group (score 8; P < .05) than in the younger group (score 4), and the ratio of patients with a modified Rankin Scale score of 4 to 6 was significantly greater in the older group (41.7%; P < .05) than in the younger group (22.2%). However, there was no difference in asymptomatic and symptomatic intracerebral hemorrhage rates between the younger and older groups (asymptomatic 20.2% v 18.8%; symptomatic 2.6% v 2.1%). Patients with edaravone showed a higher recanalization rate (61.9%; P < .01) and a better modified Rankin Scale score at 3 months poststroke (P < .01) than the nonedaravone group. CONCLUSIONS These data suggest that intravenous alteplase (0.6 mg/kg) within 3 hours of stroke onset was safe and effective, even for very old patients (≥ 80 years of age), but resulted in poor outcomes relating not to tPA but to aging. In addition, edaravone may be a good partner for combination therapy with tPA to enhance recanalization and reduce hemorrhagic transformation.

Serial diffusion-weighted MRI and SPECT findings in a Creutzfeldt-Jakob disease patient with V180I mutation

We report serial changes of diffusion-weighted imaging (DWI) and single photon emission computed tomography (SPECT) in a patient with Creutzfeldt-Jakob disease with V180I mutation (CJD180). DWI abnormalities in our patient were more predominantly observed in the left cerebral cortex than left basal ganglia. Hemilateral abnormalities progressed over 5 months to involve the contralateral side with increasing DWI signals. At 6 months, SPECT showed hypoperfusion in the left parietal and frontal lobes and the hypoperfusion region spread to the bilateral basal ganglia, right parietal and frontal lobes. SPECT imaging revealed marked cerebral blood flow reduction, predominantly in the cerebral cortex corresponding to brain areas with high-intensity DWI signals. During the follow-up period of CJD180, DWI was more sensitive than conventional FLAIR and T2-weighted images (T2WI) to detect and monitor the progression of abnormal hyperintense lesions. We suggest that serial DWI and SPECT findings are useful for not only early diagnosis of CJD but also for monitoring disease progression.

Neurovascular Protection by Telmisartan via Reducing Neuroinflammation in Stroke-Resistant Spontaneously Hypertensive Rat Brain after Ischemic Stroke

Telmisartan is a highly lipid-soluble angiotensin receptor blocker (ARB), which improves insulin sensitivity and reduces triglyceride levels and, thus, is called metabo-sartan. We examined the effects of telmisartan on neurovascular unit (N-acetylglucosamine oligomer [NAGO], collagen IV, and glial fibrillary acidic protein [GFAP]) and neuroinflammation (matrix metalloproteinase-9 [MMP-9] and inflammasome) in brain of stroke-resistant spontaneously hypertensive rat (SHR-SR). At 12 weeks of age, SHR-SR received transient middle cerebral artery occlusion (tMCAO) for 90 minutes and were divided into the following 3 groups, that is, vehicle group, low-dose telmisartan group (.3 mg/kg/d), and high-dose telmisartan group (3 mg/kg/d, postoral). Immunohistologic analysis at ages 6, 12, and 18 months showed progressive decreases of NAGO-positive endothelium and collagen IV-positive basement membrane and progressive increases of MMP-9-positive neurons, GFAP-positive astrocytes, and NLRP3-positive inflammasome in the cerebral cortex of vehicle group. Low-dose telmisartan reduced such changes without lowering blood pressure (BP), and high-dose telmisartan further improved such changes with lowering BP. The present findings suggest that a persistent hypertension caused a long-lasting inflammation after tMCAO in SHR-SR, which accelerated neurovascular disruption and emergent inflammasome, and that telmisartan greatly reduced such inflammation and protected the neurovascular unit via its pleiotropic effects in living hypertensive rat brain after ischemic stroke.

Tissue Plasminogen Activator Thrombolytic Therapy for Acute Ischemic Stroke in 4 Hospital Groups in Japan

In October 2005 in Japan, the recombinant tissue plasminogen activator (tPA) alteplase was approved for patients with acute ischemic stroke within 3 hours of onset at a dose of 0.6 mg/kg. The present study was undertaken to assess the safety and efficacy of alteplase in Japan. Between October 2005 and December 2009, a total of 114 consecutive patients admitted to 4 hospitals received intravenous tPA within 3 hours of stroke onset. Clinical backgrounds and outcomes were investigated. The patients were divided into 2 chronological groups: an early group, comprising 45 patients treated between October 2005 and December 2007, and a later group, comprising 69 patients treated between January 2008 and December 2009. The mean time from arrival at the hospital to the initiation of treatment was significantly reduced in the later group, from 82.6 minutes to 70.9 minutes. Intracerebral hemorrhage (ICH) occurred in 26 patients (22.8%); compared with patients without ICH, these patients had a significantly higher prevalence of cardiogenic embolism (88.5% vs 58.0%); greater warfarin use (26.8% vs 6.8%); higher mean National Institutes of Health Stroke Scale (NIHSS) scores on admission (16 vs 10), at 3 days after admission (14 vs 5), and at 7 days after admission (13.5 vs 3); and a lower Diffusion-Weighted Imaging-Alberta Stroke Program Early CT Score (7.8 vs 9.1). Patients who received edaravone had a higher prevalence of cardiogenic embolism (70.9% vs 36.4%), a higher recanalization rate (77.7% vs 36.4%), and lower NIHSS scores on admission and at 3 and 7 days after admission compared with those who did not receive edaravone. Our data suggest that administration of intravenous alteplase 0.6 mg/kg within 3 hours of stroke onset is safe and effective, that the NIHSS and Diffusion-Weighted Imaging-Alberta Stroke Program Early CT Score are useful predictors of ICH after tPA administration, and that warfarin-treated patients are more likely to develop symptomatic ICH despite an International Normalized Ratio <1.7.

Neurovascular protection of cilostazol in stroke-prone spontaneous hypertensive rats associated with angiogenesis and pericyte proliferation

Stroke is the major cause of death and decrease in the activities of daily living. This study sought to evaluate the effects of commonly used antiplatelet drugs on spontaneous cerebral infarction in relation to neurovascular protection associated with angiogenesis and pericyte proliferation. Stroke‐prone spontaneously hypertensive rats (SHR‐SP) were treated with vehicle, aspirin, clopidogrel, or cilostazol from 8 to 10 weeks of age. The interaction of neurovascular components among endothelial cells, pericytes, and astrocytic endfeet were immunohistochemically examined in brain sections. Angiogenesis associated with vascular endothelial growth factor receptor 2 (VEGFR2) and pericyte proliferation were also examined immunohistochemically. The expression and activity of matrix metalloproteinase 9 (MMP‐9) were assessed immunohistochemically and by gelatin zymography. Among the antiplatelet drugs, cilostazol preserved the neurovascular unit (NVU) by preventing astrocytic endfeet or pericytes from pathological detachment found in the vehicle and aspirin treatment. Cilostazol also inhibited the expression and activity of MMP‐9, which led to protection of the NVU. Furthermore, in the periinfarct area, cilostazol increased VEGFR2 expression, promoting angiogenesis through proliferation of pericytes. The present study showed a strong protection of NVU integrity by cilostazol and the promotion of angiogenesis by stimulating both endothelial VEGFR2 expression and pericyte proliferation. In addition to the antioxidative effect, these pleiotropic effects of cilostazol contribute to reduce spontaneous infarct volume and preserve motor and cognitive function in SHR‐SP.

Modifying neurorepair and neuroregenerative factors with tPA and edaravone after transient middle cerebral artery occlusion in rat brain

Changes in expression of neurorepair and neuroregenerative factors were examined after transient cerebral ischemia in relation to the effects of tissue plasminogen activator (tPA) and the free radical scavenger edaravone. Physiological saline or edaravone was injected twice during 90 min of transient middle cerebral artery occlusion (tMCAO) in rats, followed by the same saline or tPA at reperfusion. Sizes of the infarct and protein factors relating to neurorepair and neuroregeneration were examined at 4d after tMCAO. The protein factors examined were: a chondroitin sulfate proteoglycan neurocan, semaphorin type 3A (Sema3A), a myelin-associated glycoprotein receptor (Nogo receptor, Nogo-R), a synaptic regenerative factor (growth associated protein-43, GAP43), and a chemotropic factor netrin receptor (deleted in colorectal cancer, DCC). Two groups treated by edaravone only or edaravone plus tPA showed a reduction in infarct volume compared to the two groups treated by vehicle only or vehicle plus tPA. Immunohistochemistry and western blot analyses indicated that protein expression of neurocan, Sema3A, Nogo-R, GAP43, and DCC was decreased with tPA, but recovered with edaravone. Additive edaravone prevented the reductions of these five proteins induced by tPA. The present study demonstrates for the first time that exogenous tPA reduced protein factors involved in inhibiting and promoting axonal growth, but that edaravone ameliorated such damage in brain repair after acute ischemia.

Characteristic features of cognitive, affective and daily living functions of late‐elderly dementia

The world is rapidly aging, and is facing an increase of late‐elderly dementia patients. It is important to investigate the characteristic features of late‐elderly dementia in a super‐aged country.

Computerized Touch-panel Screening Tests for Detecting Mild Cognitive Impairment and Alzheimer's Disease

OBJECTIVE The increasing population of elderly people in Japan has accelerated the demand for a simple screening test to detect cognitive and affective declines in mild cognitive impairment (MCI) and the early stage of dementia. Methods We compared the cognitive and affective functions, activities of daily living (ADLs) and the results of four computerized touch-panel screening tests in 41 MCI subjects, 124 patients with Alzheimers disease (AD) and 75 age- and gender-matched normal controls. RESULTS All computerized touch-panel games were successfully used to discriminate the AD patients from the normal controls (** p<0.01). Although there were no differences in the findings of the conventional cognitive assessments, the results of the flipping cards game were significantly different (** p<0.01) between the normal controls (19.3 ± 9.5 sec) and MCI subjects (30.9 ± 18.4 sec). Three conventional affective assessments, the ADL score, Abes behavioral and psychological symptoms of dementia (ABS) (** p<0.01) and the apathy scale (AS) (* p<0.05), could be used to discriminate the MCI subjects (ABS, 0.9 ± 1.5; AS, 12.8 ± 5.9) from the normal controls (ABS, 0.1 ± 0.4; AS, 8.9 ± 5.3). CONCLUSION In the present study, all four touch-panel screening tests could be employed to discriminate AD patients from normal controls, whereas only the flipping cards game was effective for distinguishing MCI subjects from normal controls. Therefore, this novel touch-panel screening test may be a more sensitive tool for detecting MCI subjects among elderly patients.