High frequency of HTRA1 AND ABCC6 mutations in Japanese patients with adult-onset cerebral small vessel disease

BACKGROUND

This study aimed to clarify the frequency and clinical features of monogenic cerebral small vessel disease (mgCSVD) among patients with adult-onset severe CSVD in Japan.

METHODS

This study included patients with adult-onset severe CSVD with an age of onset ≤55 years (group 1) or >55 years and with a positive family history (group 2). After conducting conventional genetic tests for NOTCH3 and HTRA1, whole-exome sequencing was performed on undiagnosed patients. Patients were divided into two groups according to the results of the genetic tests: monogenic and undetermined. The clinical and imaging features were compared between the two groups.

RESULTS

Group 1 and group 2 included 75 and 31 patients, respectively. In total, 30 patients had NOTCH3 mutations, 11 patients had HTRA1 mutations, 6 patients had ABCC6 mutations, 1 patient had a TREX1 mutation, 1 patient had a COL4A1 mutation and 1 patient had a COL4A2 mutation. The total frequency of mutations in NOTCH3, HTRA1 and ABCC6 was 94.0% in patients with mgCSVD. In group 1, the frequency of a family history of first relatives, hypertension and multiple lacunar infarctions (LIs) differed significantly between the two groups (monogenic vs undetermined; family history of first relatives, 61.0% vs 25.0%, p=0.0015; hypertension, 34.1% vs 63.9%, p=0.0092; multiple LIs, 87.8% vs 63.9%, p=0.0134).

CONCLUSIONS

More than 90% of mgCSVDs were diagnosed by screening for NOTCH3, HTRA1 and ABCC6. The target sequences for these three genes may efficiently diagnose mgCSVD in Japanese patients.

Efficacy and safety of spot heating and ultrasound irradiation on in vitro and in vivo thrombolysis models

The feasibility of transcranial sonothrombolysis has been demonstrated, although little is known about the relationships between thermal or mechanical mechanisms and thrombolytic outcomes. Therefore, the present study aims to reveal the effect and safety of temperature and ultrasound through in vitro and in vivo thrombolysis models. Artificial clots in microtubes were heated in a water bath or sonicated by ultrasound irradiation, and then clots weight decrease with rising temperature and sonication time was confirmed. In the in vitro thrombotic occlusion model, based on spot heating, clot volume was reduced and clots moved to the distal side, followed by recanalization of the occlusion. In the in vivo study, the common carotid artery of rats was exposed to a spot heater or to sonication. No brain infarct or brain blood barrier disruption was shown, but endothelial junctional dysintegrity and an inflammatory response in the carotid artery were detected. The present spot heating and ultrasound irradiation models seem to be effective for disintegrating clots in vitro, but the safety of the in vivo model was not fully supported by the data. However, the data indicates that a shorter time exposure could be less invasive than a longer exposure.

Bilateral Magnetic Resonance Imaging-Guided Focused Ultrasound Thalamotomy for Essential Tremor

INTRODUCTION

Essential tremor is the most common movement disorder in adults. Bilateral symptoms are typical; however, bilateral thalamotomy for essential tremor is associated with a high probability of adverse events. We retrospectively investigated the efficacy and safety of staged bilateral ventral intermediate nucleus thalamotomy for refractory essential tremor using magnetic resonance imaging-guided focused ultrasound.

METHODS

We enrolled 5 consecutive patients with refractory essential tremor between September 2016 and March 2020. Patients underwent a second operation at least 1 year after the first operation. The second lesion was created asymmetrically to the first lesion.

RESULTS

Mean patient age was 57.6 years, and the mean interval between the 2 operations was 27.8 months. The second lesion center was superior to the first lesion in all patients. The mean baseline, second preoperative, and second postoperative Clinical Rating Scale for Tremor total scores were 63.6, 49.2, and 21.8, respectively. The mean baseline, second preoperative, and second postoperative Clinical Rating Scale for Tremor part C scores were 18.4, 8.2, and 2.6, respectively. One patient had permanent adverse events of slight dysarthria and discomfort in the tongue. No patient experienced dysphagia or cognitive dysfunction after the second operation. Four of the 5 patients were satisfied with the results of the bilateral treatment, including the patient who had permanent adverse events.

CONCLUSIONS

Magnetic resonance imaging-guided focused ultrasound is an effective method for bilateral thalamotomy when adhering to the following considerations: (1) asymmetrical lesions are created and (2) sufficient interval (>1 year) between operations.

Early detection of cognitive decline in mild cognitive impairment and Alzheimer's disease with a novel eye tracking test

Due to an increasing number of dementia patients, the development of a rapid and sensitive method for cognitive assessment is awaited. Here, we examined the usefulness of a novel and short (3 min) eye tracking device to evaluate the cognitive function of normal control (NC, n = 52), mild cognitive impairment (MCI, n = 52), and Alzheimer's disease (AD, n = 70) subjects. Eye tracking total score declined significantly in MCI (**p < 0.01 vs NC) and AD (**p < 0.01 vs NC, ^##p < 0.01 vs MCI), and correlated well with the mini-mental state examination (MMSE) score (r = 0.57, *p < 0.05). Furthermore, the eye tracking test, especially memory and deductive reasoning tasks, effectively discriminated NC, MCI and AD. The present novel eye tracking test clearly discriminated cognitive functions among NC, MCI, and AD subjects, thereby providing an advantage for the early detection of MCI and AD in screening.

A New Serum Biomarker Set to Detect Mild Cognitive Impairment and Alzheimer's Disease by Peptidome Technology

Background:

Because dementia is an emerging problem in the world, biochemical markers of cerebrospinal fluid (CSF) and radio-isotopic analyses are helpful for diagnosing Alzheimer’s disease (AD). Although blood sample is more feasible and plausible than CSF or radiological biomarkers for screening potential AD, measurements of serum amyloid- β (Aβ), plasma tau, and serum antibodies for Aβ_1 - 42 are not yet well established.

Objective:

We aimed to identify a new serum biomarker to detect mild cognitive impairment (MCI) and AD in comparison to cognitively healthy control by a new peptidome technology.

Methods:

With only 1.5μl of serum, we examined a new target plate “BLOTCHIP^®” plus a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/MS) to discriminate control (n = 100), MCI (n = 60), and AD (n = 99). In some subjects, cognitive Mini-Mental State Examination (MMSE) were compared to positron emission tomography (PET) with Pittsburgh compound B (PiB) and the serum probability of dementia (SPD). The mother proteins of candidate serum peptides were examined in autopsied AD brains.

Results:

Apart from Aβ or tau, the present study discovered a new diagnostic 4-peptides-set biomarker for discriminating control, MCI, and AD with 87% of sensitivity and 65% of specificity between control and AD (^***p < 0.001). MMSE score was well correlated to brain Aβ deposition and to SPD of AD. The mother proteins of the four peptides were upregulated for coagulation, complement, and plasticity (three proteins), and was downregulated for anti-inflammation (one protein) in AD brains.

Conclusion:

The present serum biomarker set provides a new, rapid, non-invasive, highly quantitative and low-cost clinical application for dementia screening, and also suggests an alternative pathomechanism of AD for neuroinflammation and neurovascular unit damage.

4-Hydroxyl-2-Nonenal Localized Expression Pattern in Retrieved Clots is Associated with Large Artery Atherosclerosis in Stroke Patients

OBJECTIVES

The relationship between stroke etiology and clot pathology remains controversial.

MATERIALS AND METHODS

We performed histological analysis of clots retrieved from 52 acute ischemic stroke patients using hematoxylin and eosin staining and immunohistochemistry (CD42b and oxidative/hypoxic stress markers). The correlations between clot composition and the stroke etiological group (i.e., cardioembolic, cryptogenic, or large artery atherosclerosis) were assessed.

RESULTS

Of the 52 clots analyzed, there were no significant differences in histopathologic composition (e.g., white blood cells, red blood cells, fibrin, and platelets) between the 3 etiological groups (P = .92). By contrast, all large artery atherosclerosis clots showed a localized pattern with the oxidative stress marker 4-hydroxyl-2-nonenal (P < .01). From all 52 clots, 4-hydroxyl-2-nonenal expression patterns were localized in 28.8% of clots, diffuse in 57.7% of clots, and no signal in 13.5% of clots.

CONCLUSIONS

A localized pattern of 4-hydroxyl-2-nonenal staining may be a novel and effective marker for large artery atherosclerosis (sensitivity 100%, specificity 82%).

Improvement of a decreased anti-oxidative activity by edaravone in amyotrophic lateral sclerosis patients

BACKGROUND

The free radical scavenger edaravone is a proven neuroprotective drug for patients with amyotrophic lateral sclerosis (ALS). Our objective was to evaluate the therapeutic effects of edaravone for oxidative stress and anti-oxidative activity in ALS patients.

METHODS

Twenty-two ALS patients with a disease duration of 2 years, treated by edaravone, and 25 control participants were evaluated according to their clinical scores, including ALS functional rating scale-revised (ALSFRS-R), and serum and cerebrospinal fluid (CSF) markers of oxidative stress dROM and anti-oxidative activity OXY.

RESULTS

Serum and CSF markers of anti-oxidative activity OXY were significantly decreased in ALS patients at pre-treatment compared with controls (^##p < .01), which was improved in the course of edaravone treatment. Both serum and CSF OXY were significantly correlated with ALS clinical scores including ALSFRS-R (*p < .05, **p < .01, ***p < .001). Furthermore, serum OXY at pre-treatment was significantly correlated with a change in the ALSFRS-R score in the sixth cycle of edaravone treatment (*p < .05).

CONCLUSIONS

The present study suggests significant correlations between anti-oxidative activity and ALS clinical severity, and the therapeutic efficacy of edaravone for decreased anti-oxidative activity in ALS.

Neuroprotective effect of CuATSM in mice stroke model by ameliorating oxidative stress

Cu-diacetyl-bis (N4-methylthiosemicarbazone) (CuATSM) has both anti-oxidative and anti-inflammatory activities, but its therapeutic efficacy for oxidative stress has not been thoroughly investigated in acute ischemic stroke. Here, the present study was designed to assess the efficacies of CuATSM in acute ischemic stroke by comparing with the standard neuroprotective reagent edaravone. Mice were subjected to transient middle cerebral occlusion (tMCAO) for 60 min, and then intravenously administrated with CuATSM (1.5 mg/kg) or edaravone (3 mg/kg) just after the reperfusion, and examined at 1 and 3 d. Compared with the vehicle group, CuATSM treatment decreased infarct volumes and oxidative stress at 3d after tMCAO, which was further enhanced by combined CuATSM + edaravone treatment as compared with single CuATSM group, but not improve neurobehaviors. The present study demonstrated that CuATSM showed strong antioxidative and neuroprotective effects in acute ischemic stroke, which was enhanced by the combination with edaravone.

Different clinical and neuroimaging features of Japanese dementia siblings with a new N-terminal mutation (Val225Ala) of APP gene

Autosomal dominant amyloid precursor protein (APP) mutations in familial Alzheimer's disease accelerate the amyloid beta (Aβ) pathology. Here we describe Japanese siblings with a new N-terminal mutation (a heterogeneous c.674T>C, p.Val225Ala) of the APP gene, developing a progressive dementia at 57 years and Aβ and tau pathologies in cerebrospinal fluid studies. However, the brother and sister showed different clinical and neuroimaging features, suggesting different Aβ pathologies for each sibling.

Early Emergence of Neuropsychiatric Symptoms in Cognitively Normal Subjects and Mild Cognitive Impairment

The world is rapidly aging and facing an increase in the number of dementia patients, so it is important to detect the preclinical stage of dementia in such countries. We examined both cognitive and affective functions among cognitively normal control (n = 218), mild cognitive impairment (MCI, n = 146), and Alzheimer's disease (AD, n = 305) subjects using two evaluation tools for behavioral and psychological symptoms of dementia (BPSD) [Abe's BPSD score (ABS) and mild behavioral impairment (MBI)]. BPSD were present in 12.4% (ABS) and 9.6% (MBI) of cognitively normal people, 34.9% and 32.2% in MCI subjects, and 66.2% and 51.1% in AD patients. Both ABS (§p<0.05) and MBI (§§p < 0.01) score showed worse score with cognitive decline of the Mini-Mental State Examination in the AD group in BPSD-positive participants. Similar correlations were found in all participants in AD group (||||p < 0.01 versus ABS and MBI). Among the subscales in BPSD-positive participants, an apathy/indifference score of ABS and a decreased motivation of MBI showed significant differences in AD patients compared to the control and MCI subjects (**p<0.01). In addition, subscale analyses further showed a downward trend from the control to MCI and AD subjects in four ABS subscales and three MBI subscales. The present study showed the preclinical presence of BPSD in cognitively normal people, more so in MCI subjects, and ABS detected BPSD more sensitively than MBI in all three groups.