Yasuhito Wakasaya

Quantification of cystatin C in cerebrospinal fluid from various neurological disorders and correlation with G73A polymorphism in CST3

Cystatin C (CC) is a cysteine protease inhibitor abundantly expressed in the central nervous system. Bunina bodies, small eosinophilic intraneuronal inclusions, are stain positive for CC and are the most specific histological hallmark of amyotrophic lateral sclerosis (ALS). In this study, employing a latex turbidimetric immunoassay, levels of CC in cerebrospinal fluid (CSF) were quantified in 130 age-matched individuals with either a neurological disorder [ALS, Alzheimers disease (AD), Parkinsons disease (PD), tauopathy (TP), multiple system atrophy (MSA), chronic inflammatory demyelinating polyneuropathy (CIDP)] or no known neurological condition (normal control, NC). The CC level in CSF was found to be correlated with the age during the investigation but not the protein concentration. There was no difference in CC levels between NC and ALS or CIDP cases, whereas CC levels were significantly lower in MSA compared with NC. Of the 130 cases, 96 were genotyped, and G/A or A/A polymorphism at +73 within the CST3 gene was found in 28 individuals. The CC level was significantly lower in the combined group of G/A and A/A genotypes compared with G/G. The present data demonstrate that the level of CC in CSF should not be considered as a biomarker of ALS, but there is a correlation between CC levels and the CST3 genotype.

Amyloid β accelerates phosphorylation of tau and neurofibrillary tangle formation in an amyloid precursor protein and tau double-transgenic mouse model

In Alzheimers disease, Aβ deposits are considered the initial cardinal events that induce tauopathy secondarily. However, the relationship between Aβ amyloidosis and tauopathy has not been determined in detail. We produced double transgenic mice, 2×TgTau+/–APP+/–, by mating Tg2576 mice that exhibit Aβ amyloidosis and TgTauP301L mice that show tauopathy, and statistically analyzed the effect of Aβ accumulation on tauopathy. There was no significant difference in theprogression of Aβ accumulation among 2×TgTau+/–APP+/– and 1×TgTau−/–APP+/–, and tau accumulation among 2×TgTau+/−APP+/− and 1×Tg Tau+/–APP−/–. The appearance rates of phosphorylated tau developing in neurons and processes were significantly accelerated in 2×TgTau+/–APP+/– mice compared with those in 1×TgTau+/–APP−/– mice at 23 months of age. Accumulation of phosphorylated and confomationally altered tau and GSK3β in neuronal processes was accelerated in the white matter in 2×TgTau+/–APP+/–. The level of phosphorylated tau in the sarkosyl‐insoluble fraction was increased in 2×TgTau+/–APP+/– brains compared with that in 1×TgTau+/–APP−/– brains. Thus, Aβ amyloid partially enhances tauopathy through accumulation of insoluble, phosphorylated, and conformationally changed tau in neuronal cytoplasm and processes in the late stage.

Factors responsible for neurofibrillary tangles and neuronal cell losses in tauopathy

TgTauP301L mice that overexpress the mutant human tauP301L present in FTDP‐17 reproduce neurofibrillary tangles (NFTs), neuronal cell losses, memory disturbance, and substantial phenotypic variation. To demonstrate factors responsible for NFT formation and neuronal cell losses, sets of TgTauP301L for comparison with or without NFTs and neuronal cell losses were studied with oligonucleotide microarrays. Gene expressions were altered in biological pathways, including oxidative stress, apoptosis, mitochondrial fatty acid betaoxidation, inflammatory response pathway, and complement and coagulation cascade pathways. Among 24 altered genes, increased levels of apolipoprotein D (ApoD) and neuronal PAS domain protein 4 (Npas4) and decreased levels of doublecortin (DCX) and potassium channel, voltage‐gated, shaker‐related subfamily, β member 1 (Kcnab1) were found in the TgTauP301L with NFTs and neuronal cell losses, Alzheimers brains, and tauopathy brains. Thus, many biological pathways and novel molecules are associated with NFT formation and neuronal cell losses in tauopathy brains.

Disease Modifying Therapies for Alzheimer's Disease Targeting Aβ Oligomers: Implications for Therapeutic Mechanisms

Several lines of evidence indicate that amyloid β (Aβ), particularly Aβ oligomers (AβOs), plays a causative role in Alzheimers disease. However, the mechanisms underlying the action of an anti-AβO antibody to clarify the toxic action of AβOs remain elusive. Here, we showed that the anti-AβO antibody (monoclonal 72D9) can modify the Aβ aggregation pathway. We also found that 72D9 directly sequesters both extracellular and intraneuronal AβOs in a nontoxic state. Thus, therapeutic intervention targeting AβOs is a promising strategy for neuronal protection in Alzheimers disease.

An Unusual Case of Elderly-Onset Cerebral Autosomal Dominant Arteriopathy With Subcortical Infarcts and Leukoencephalopathy (CADASIL) With Multiple Cerebrovascular Risk Factors

Here we report a female patient with elderly-onset cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). At age 71, she developed gait disturbance, followed by memory disturbance 1 year later. She had been treated for hypertension and diabetes mellitus for 19 years. There apparently was low penetrance of disease. Magnetic resonance imaging (MRI) findings showed typical features of CADASIL, and the R607C mutation was detected in exon 11 in NOTCH3. This case strongly indicates that CADASIL should be considered when typical findings are observed on MRI even in cases of elderly onset with multiple cerebrovascular risk factors.

A novel mutation in the arylsulfatase A gene associated with adult-onset metachromatic leukodystrophy without clinical evidence of neuropathy.

! 45 and 47, respectively. His parents were not consanguineous and there is no previous history of similar neurological diseases in the family. Examination of the optic fundi showed no abnormal findings. He had no numbness, paresthesia, muscle weakness, muscle atrophy, abnormal involuntary movements or ataxia. Superficial sensation was normal, but vibratory sense was very slightly impaired in the lower limbs. The deep tendon reflexes were normal in the upper limbs. The patellar tendon reflexes were bilaterally increased, and the bilateral Achilles tendon reflexes were mildly diminished. The plantar responses were bilaterally extensor, but no spasticity was observed. Brain MRI revealed severe symmetrical white matter hyperintensities in the periventricular area on T2-weighted images and cerebral atrophy. Results from nerve conduction studies Dear Sir, Metachromatic leukodystrophy (MLD, MIM 250100) is an autosomal recessive hereditary disease characterized by neurological symptoms such as cognitive and behavioral abnormalities, ataxia and seizures [1] . MLD results from deficiency of arylsulfatase A (ASA), resulting in sulfatide accumulation in the central and peripheral nervous system [1] . A number of mutations in the ASA gene associated with decreased activity of ASA have been reported in patients with MLD [1] . Here we report a male patient with adult-onset MLD who is compound heterozygous for a novel nonsense mutation (C38X) (TGC ] TGA) and a known missense mutation (T409I) (ACT ] ATT) [2, 3] . Of note, this patient showed severely decreased nerve conduction velocities without obvious external clinical signs of neuropathy, normally a characteristic feature of MLD. The absence of clear external signs contributed to initial misdiagnosis. The 33-year-old male developed irritability and disorientation and visited a hospital department of psychiatry. There he was diagnosed with schizophrenia and, although he continued to take medications Received: November 21, 2007 Accepted: January 28, 2008 Published online: October 3, 2008

Case of elderly-onset multiple acyl-CoA dehydrogenase deficiency with a novel ETFDH mutation shows progressive muscle weakness and rhabdomyolysis

A 59‐year‐old female, who had developed muscle stiffness and progressive muscle weakness 11 months earlier, was admitted to our hospital with acute rhabdomyolysis and muscle weakness of the neck and extremities. Markedly elevated levels of muscle enzymes, including creatine kinase, and severe metabolic acidosis were observed. A muscle biopsy revealed lipid storage myopathy. Genetic analysis detected a novel mutation in the electron‐transferring flavoprotein dehydrogenase (ETFDH) gene (c.547A > T (p.M183L)). The administration of high‐dose (120 mg/day) riboflavin rapidly improved the patients symptoms and laboratory data, and she did not exhibit any symptoms at the 4‐year follow‐up. In this case of elderly‐onset multiple acyl‐CoA dehydrogenation deficiency, high‐dose riboflavin treatment produced a marked improvement in the patients condition.

CSF AND PLASMA BIOMARKERS FOR DIAGNOSING DEMENTIA IN OUTPATIENT CLINIC

Background:Not necessary all diagnostic test data used in neurodegenerative diseases are needed to reach high diagnostic accuracy for all patients. A simple battery of tests may provide enough information for accurate diagnosis in some cases while a complete test battery may be needed in other more challenging cases. The objective of this work is to study whether a systematic stratified diagnostic workflow could enable more cost-efficient diagnostics. Methods: The data from five diagnostics groups were used (Table 1). The data consisted of clinical and neuropsychological test data, CSF-biomarkers and MRI-data (T1 & FLAIR) quantified using both visual ratings and automatically computed imaging biomarkers. For the stratified approach, the data were grouped into five batteries and a cost was given to each battery: NP-S (MMSE, memory tests, fluency tests and trail makings tests, 100 V), NP-F (full neuropsychological battery, NP-S being a subset, 300 V), MRI-V (MRI data acquisition including visual scorings, 400 V), MRI-A (additional imaging biomarkers from six quantification tools, 80 V) and CSF-biomarkers (300 V). Figure 1 shows a schematic presentation of the stratified workflow. The disease-state index (DSI) method, extended to differential diagnostics, was used to assess patients’ fit to previously diagnosed cases in the database [1]. A patient was labeled as ‘clear’ if DSI was higher than a given threshold for a certain combination of batteries. The threshold producing the accuracy>85% for the clear cases was chosen. No extra cost was given to wrong diagnosis or to undiagnosed cases needing follow-up. Cross-validation was used in validation. Results: Table 2 and Figure 2 show the results. The best sequence was when stratification was used with automatically computed imaging biomarkers: the cost per patient was 741 V, 73.6 % of all cases were labeled as clear and the accuracy for the clear cases was 85.7 %. Conclusions: The results show that the stratified approach has potential to reduce costs in diagnostics. In addition, imaging biomarkers from automated tools can be beneficial. [1] J. Mattila et al., Disease State Fingerprint for Evaluating the State of Alzheimer’s Disease in Patients. Journal of Alzheimer’s Disease 27: 163-176, 2011.

Factors responsible for neurofibrillary tangle formation and neuronal cell death in tauopathy brains

Background: TgTauP301L that overexpresses mutant human tauP301L present in FTDP-17 reproduces neurofibrillary tangles (NFT), neuronal death, memory disturbance and substantial phenotypic variation. Methods: To reveal factors responsible for NFT formation and neuronal death, comparison sets of TgTauP301L with or without NFT and neuronal cell losses were studied using oligonucleotide microarrays. Results: Results indicate that alteration of gene expressions in biological pathways including oxidative stress, apoptosis, mitochondrial fatty acid betaoxidation, inflammatory response pathway, complement and coagulation cascades pathway and EGFR1pathway. Reactive increased Apolipoprotein D for NFT neurotoxicity and decreased doublecortin according to suppressed neurogenesis were observed. Conclusions: These findings indicate that NFT formations and neuronal cell losses occur under alterations of many biological pathways, especially oxidative stress, apoptosis, mitochondrial dysfunction, inflammation, cell cycle and signal transductions in tauopathy brains.