Publications by authors named "Taiji Tsunemi"

Article Synopsis
  • Lewy body diseases, including Parkinson's disease, involve the spread of a protein called alpha-synuclein (αSyn) between neurons, making it important to study for treatment development.
  • The research focused on how neuronal activity affects the release of αSyn from dopaminergic neurons derived from human stem cells, comparing healthy neurons to those with a PD-related gene mutation.
  • Findings showed that increased neuronal activity boosts αSyn release, while decreased activity reduces it, highlighting the role of neuronal activity in the spread of Lewy pathology and suggesting potential new treatment strategies for neurodegenerative diseases.
View Article and Find Full Text PDF

Both transient epileptic amnesia (TEA) and transient global amnesia (TGA) are clinically characterized by temporary amnesic symptoms. TEA involves recurring amnesic episodes, while TGA typically manifests as a singular occurrence. TGA rarely occurs repeatedly, known as recurrent TGA (r-TGA), which complicates differentiation, and raises the possibility of overlap between two disorders.

View Article and Find Full Text PDF

Mutations in the SNCA gene, which encodes α-synuclein (α-syn), play a key role in the development of genetic Parkinson's disease (PD). α-Syn is a major component of Lewy bodies in PD and glial cytoplasmic inclusions in multiple system atrophy (MSA). Rapid eye movement sleep behavior disorder patients often progress to PD, dementia with Lewy bodies, or MSA, which are collectively known as α-synucleinopathies.

View Article and Find Full Text PDF
Article Synopsis
  • Parkinson's disease (PD) is marked by the presence of Lewy bodies, which are made up of a protein called α-synuclein, and there is evidence suggesting that extracellular vesicles (EVs) help spread this pathology in the nervous system.
  • In a study analyzing serum EVs from various groups (including PD patients and healthy controls), researchers found a significant drop in EV numbers in PD patients, but an increase in filamentous α-synuclein within these EVs, indicating a potential link to the disease.
  • The results suggest that serum α-synuclein filaments in EVs could serve as useful diagnostic markers for diseases related to α-synuclein, and they highlight the role of EV
View Article and Find Full Text PDF

Background: Chronic constipation is a common digestive complication of Parkinson's disease (PD).

Objectives: To verify the usefulness of elobixibat, an ileal bile acid transporter inhibitor, for chronic constipation in PD.

Methods: This double-blind, placebo-controlled study consisted of a 2-week observation/washout period and a 4-week treatment period.

View Article and Find Full Text PDF

Abnormal α-synuclein aggregation is a key pathological feature of a group of neurodegenerative diseases known as synucleinopathies, which include Parkinson's disease (PD), dementia with Lewy bodies and multiple system atrophy (MSA). The pathogenic β-sheet seed conformation of α-synuclein is found in various tissues, suggesting potential as a biomarker, but few studies have been able to reliably detect these seeds in serum samples. In this study, we developed a modified assay system, called immunoprecipitation-based real-time quaking-induced conversion (IP/RT-QuIC), which enables the detection of pathogenic α-synuclein seeds in the serum of individuals with synucleinopathies.

View Article and Find Full Text PDF

Retrograde transport of lysosomes is recognised as a critical autophagy regulator. Here, we found that acrolein, an aldehyde that is significantly elevated in Parkinson's disease patient serum, enhances autophagy by promoting lysosomal clustering around the microtubule organising centre via a newly identified JIP4-TRPML1-ALG2 pathway. Phosphorylation of JIP4 at T217 by CaMK2G in response to Ca fluxes tightly regulated this system.

View Article and Find Full Text PDF

After establishing latent infection, some viruses can be reactivated by the alteration of host immunological conditions. First, we reviewed viruses that can cause neuronal damage by reactivation. Then we focused on the herpes simplex virus (HSV).

View Article and Find Full Text PDF
Article Synopsis
  • Missense variants in the LRRK2 gene are linked to both familial and sporadic forms of Parkinson's disease (PD), with differing pathological features among patients.
  • A case study discussed features a patient with the LRRK2 G2385R variant, who experienced early responsive parkinsonism and advanced visual hallucinations, along with significant brain pathology.
  • Findings included the presence of Lewy bodies, neurofibrillary tangles, and biochemical changes indicating increased LRRK2 activity, which contribute to the damaging brain environment seen in this variant of PD.
View Article and Find Full Text PDF
Article Synopsis
  • * Brain imaging indicated that the patient had progressive brain calcification, initially linked to her treatment for a craniopharyngioma 14 years prior.
  • * Although parkinsonism has not been previously reported as a symptom of radiation-induced calcification, the extent of calcification affecting the brain's white matter likely contributed to her motor issues.
View Article and Find Full Text PDF
Article Synopsis
  • A clinical trial was conducted to test the efficacy and safety of ultrahigh-dose methylcobalamin in patients with ALS diagnosed within a year of onset, indicating a need for better treatments given the limited effectiveness of current drugs.
  • The study was multicenter, double-blind, and placebo-controlled, enrolling 130 patients from Japan, who received either the methylcobalamin treatment or a placebo for 16 weeks.
  • The main outcome measured was the change in the Revised ALS Functional Rating Scale score, with results showing a significant number of patients observed completing the trial, highlighting the continued investigation into the drug's potential benefits for ALS.
View Article and Find Full Text PDF
Article Synopsis
  • * Researchers compared two groups of patients: those with iNPH alone and those with iNPH accompanied by PD/PDD, analyzing data from 2010 to 2019 to assess clinical improvement and brain volume changes after surgery.
  • * Findings indicated that having PD/PDD worsens patients' clinical outcomes, though LPS surgery still led to improvements in symptoms and overall survival, thereby supporting the recommendation for surgery even in patients
View Article and Find Full Text PDF
Article Synopsis
  • Chronic constipation significantly affects the quality of life for patients with Parkinson's disease, and the laxative elobixibat's effectiveness in treating this condition is being evaluated through a controlled study.
  • The study includes a 2-week observation phase followed by a 4-week treatment period where patients track their bowel movements and medication use, comparing elobixibat to a placebo.
  • To ensure ethical compliance, the research follows strict guidelines and the findings will be shared through an online study registry after completion.
View Article and Find Full Text PDF

Late relapse of herpes simplex encephalitis (HSE) is defined as the recurrence of HSE more than 3 months after the initial exposure. The postoperative diagnosis of HSE following neurosurgery is complicated because the clinical presentation can mimic other common complications of neurosurgery. Cerebrospinal fluid polymerase chain reactions (CSF-PCR) is the gold standard for the diagnosis of HSE.

View Article and Find Full Text PDF

Objective: This study aimed to determine the prevalence and clinical features of Parkinson's disease (PD)/PD dementia (PD/PDD) or dementia with Lewy bodies (DLB) in idiopathic normal pressure hydrocephalus (iNPH).

Methods: Patients with iNPH who were admitted to the Department of Neurology, Juntendo University School of Medicine over the past 10 years have been retrospectively analyzed. The diagnosis of iNPH and concomitant PD/PDD or DLB was established using diagnostic criteria.

View Article and Find Full Text PDF

Glucocerebrosidase (GCase), which is encoded by the GBA1 gene, has lysosomal glycoside hydrolase activity that hydrolyzes glucosylceramide. Defects in GCase lead to the accumulation of glucosylceramide, which causes the development of the lysosomal storage disease known as Gaucher's disease. Loss-of-function mutations in the GBA1 gene are the most important genetic risk factor for synucleinopathies, such as Parkinson's disease and dementia with Lewy bodies.

View Article and Find Full Text PDF

Alpha synuclein (α-Syn), a presynaptic protein with unknown function, is accumulated in Lewy bodies/neurites that are one of the hallmark pathologies of Parkinson's disease (PD). Missense or multiplication mutations in SNCA, which codes α-Syn, result in a genetic form of PD, further indicating the involvement of α-Syn in PD pathogenesis. Recent pathological and experimental studies suggest that α-Syn possesses a secretory feature, as it is detected in the culture media, in the cerebrospinal fluid, and even in the blood.

View Article and Find Full Text PDF

Advanced Parkinson's disease is inconsistently defined, and evidence is lacking in relation to device-aided therapies. To update existing reviews of intrajejunal infusion of levodopa/carbidopa (LCIG), we performed a literature search for relevant articles (to November 3, 2020) using PubMed supplemented by hand searching. Retrieved articles were categorized by relevance to identified research questions, including motor complications and symptoms; nonmotor symptoms; functioning, quality of life, and caregiver burden; optimal timing of treatment initiation and administration duration; discontinuation; and complications.

View Article and Find Full Text PDF

The pathologic hallmark of Parkinson's disease is the accumulation of α-synuclein-containing Lewy bodies/neurites almost exclusively in neurons, and rarely in glial cells. However, emerging evidence suggests that glia such as astrocytes play an important role in the development of α-synuclein pathology. Using induced pluripotent stem-derived dopaminergic neurons and astrocytes from healthy subjects and patients carrying mutations in lysosomal , a monogenic form of synucleinopathy, we found that astrocytes rapidly internalized α-synuclein, and exhibited higher lysosomal degradation rates compared with neurons.

View Article and Find Full Text PDF

Introduction: Antiphospholipid syndrome (APS) is an autoimmune disorder characterized by thromboembolic events, including ischemic stroke or complications in pregnancy, and the presence of antiphospholipid antibodies. Cervical artery dissection (CAD) is not an uncommon cause of stroke in young adults. The concomitant presence of APS and CAD is extremely rare.

View Article and Find Full Text PDF