Publications by authors named "Toshiaki Kume"

Atopic dermatitis (AD) is one of the most prevalent intractable chronic itch diseases worldwide. In recent years, new molecular-targeted drugs have emerged, but side effects and economic challenges remain. Therefore, since it is important for AD patients to have a wider range of treatment options, it is important to explore new therapeutic agents.

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The therapeutic benefits of photobiomodulation (PBM) in pain management, although well documented, are accompanied by concerns about potential risks, including pain, particularly at higher laser intensities. This study investigated the effects of laser intensity on pain perception using behavioral and electrophysiological evaluations in rats. Our results show that direct laser irradiation of 1000 mW/cm to the sciatic nerve transiently increases the frequency of spontaneous firing in the superficial layer without affecting the deep layer of the spinal dorsal horn, and this effect reverses to pre-irradiation levels after irradiation.

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Article Synopsis
  • Photobiomodulation (PBM) is being investigated as a treatment for chronic pain, particularly its effects on neuronal firing in different layers of the spinal dorsal horn.
  • Previous studies showed PBM effectively inhibits pain-related neuronal activity in the superficial layers but its impact on deeper layers receiving innocuous stimuli was not well understood.
  • This study found that while PBM reduced pain-related firing in the superficial layers significantly, it did not alter firing rates in the deep layers, indicating PBM's potential to alleviate pain without compromising the sense of touch.
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. The aim of this study was to assess the repeatability of the SUV normalized by liver volume (SUVL) between two liver receptor SPECT/CT studies performed on different days in patients with ICG-R15 values within normal range..

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The pain matrix, which includes several brain regions that respond to pain sensation, contribute to the development of chronic pain. Thus, it is essential to understand the mechanism of causing chronic pain in the pain matrix such as anterior cingulate (ACC), or primary somatosensory (S1) cortex. Recently, combined experiment with the behavior tests and in vivo calcium imaging using fiber photometry revealed the interaction between the neuronal function in deep brain regions of the pain matrix including ACC and the phenotype of chronic pain.

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Chinese artichoke tuber (Stachys sieboldii Miq.) is used as an herbal medicine as well as edible food. This study examined the effect of the Chinese artichoke extracts on the nuclear factor erythroid 2-related factor 2 (Nrf2)-antioxidant response element (ARE) pathway that induces the expression of antioxidant enzymes to explore its novel characteristics.

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Amyloid β-protein (Aβ42) aggregates have been demonstrated to induce cognitive decline and neurodegeneration in Alzheimer's disease (AD). Thus, functional food ingredients that inhibit Aβ42 aggregation are valuable for AD prevention. Although several food ingredients have been studied for their anti-aggregation activity, information on their bioavailability in the brain, incorporated forms, and relevance to AD etiology is limited.

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Photobiomodulation is an effective treatment for pain. We previously reported that the direct laser irradiation of the exposed sciatic nerve inhibited firing in the rat spinal dorsal horn evoked by mechanical stimulation, corresponding to the noxious stimulus. However, percutaneous laser irradiation is used in clinical practice, and it is unclear whether it can inhibit the firing of the dorsal horn.

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Preoperative assessment of the degree of liver fibrosis is important to determine treatment strategies. In this study, galactosyl human serum albumin single-photon emission-computed tomography and ethoxybenzyl (EOB) contrast-enhanced magnetic resonance imaging (MRI) were used to assess the changes in hepatocyte function after liver fibrosis, and the standardized uptake value (SUV) was combined with gadolinium EOB-diethylenetriaminepentaacetic acid to evaluate its added value for liver fibrosis staging. A total of 484 patients diagnosed with hepatocellular carcinoma who underwent liver resection between January 2010 and August 2018 were included.

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Photobiomodulation has analgesic effects via inhibition of nerve activity, but few reports have examined the effects on the spinal dorsal horn, the entry point for nociceptive information in the central nervous system. In this study, we evaluated the effects of laser irradiation of peripheral nerve axons, which are conduction pathways for nociceptive stimuli, on the neuronal firing in lamina II of the spinal dorsal horn of a rat evoked by mechanical stimulation with von Frey filaments (vFF). In order to record neuronal firing, electrodes were inserted into lamina II of the exposed rat spinal dorsal horn.

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Amyloid β (Aβ) plays a key role in the pathology of Alzheimer's disease (AD) and is toxic owing to its ability to aggregate into oligomers and fibrils. Aβ has high aggregative ability and potent toxicity due to the "toxic turn" at positions 22 and 23. Furthermore, APP knock-in mice producing E22P-Aβ with the toxic turn exhibited AD-related phenotypes such as cognitive impairment, Aβ plaque accumulation, and tau hyperphosphorylation.

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Alzheimer's disease (AD) is a progressive neurodegenerative disorder that requires further pathological elucidation to establish effective treatment strategies. We previously showed that amyloid β (Aβ) toxic conformer with a turn at positions 22-23 is essential for forming highly toxic oligomers. In the present study, we evaluated phenotypic changes with aging in AD model (NL-P-F) mice with Swedish mutation (NL), Iberian mutation (F), and mutation (P) overproducing E22P-Aβ, a mimic of toxic conformer utilizing the knock-in technique.

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The skin is an important barrier that protects against invasion by foreign substances, including irritants and harmful microorganisms, and holds water in the body. Washing the skin with cleansers and shampoos containing anionic surfactants, for example sodium dodecyl sulfate (SDS), is important for maintaining skin homeostasis. However, surfactants can cause dermatitis, cutaneous hypersensitivity (e.

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Since amyloid β (Aβ) oligomers are more cytotoxic than fibrils, various dimer models have been synthesized. We focused on the C-terminal region that could form a hydrophobic core in the aggregation process and identified a toxic conformer-restricted dimer model (E22P,G38DAP-Aβ40 dimer) with an l,l-2,6-diaminopimelic acid linker ( = 3) at position 38, which exhibited moderate cytotoxicity. We synthesized four additional linkers ( = 2, 4, 5, 7) to determine the most appropriate distance between the two Aβ40 monomers for a toxic dimer model.

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Some chemical Nrf2 inducers possess antioxidant and anti-inflammatory properties. TPNA10168, which was identified from a chemical library as a potential activator of the Keap1-Nrf2-ARE pathway, exhibits a neuroprotective effect against oxidative stress-induced injury. However, it has not been investigated as an anti-inflammatory agent.

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Article Synopsis
  • Amyloid β (Aβ) oligomers are crucial in causing Alzheimer's disease, with a focus on a specific form of Aβ42 that has a unique disulfide bond structure.
  • Researchers created three modified versions of Aβ42, using different combinations of cysteine and homocysteine, and found that most of these variants were highly toxic to specific cell lines, while one variant was not.
  • The study revealed that the toxic effects were tied more to the specific shape (conformation) of Aβ42 than to its clustering into larger oligomers, as shown by various experimental methods.
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Mechanical stimulation of cultured keratinocytes and a living epidermis increases intracellular calcium ion concentrations ([Ca]) in stimulated cells. This action propagates a Ca wave to neighboring keratinocytes via ATP/P2Y receptors. Recent behavioral, pharmacological studies revealed that exogenous ATP induces itching via P2X receptors in mice.

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Article Synopsis
  • - The study explores the impact of different ROI (region of interest) settings on the enhancement effect ratio using EOB contrast for assessing liver fibrosis, emphasizing that traditional methods can be time-consuming.
  • - Researchers compared three ROI configurations: placing one ROI in each Quinault segment, two in each lobe, and four total (two in each lobe), with varying sizes of 1 cm, 4 cm, and maximum fit area.
  • - The findings suggest that using four ROIs of 4 cm or larger enhances reproducibility in calculations, improving efficiency in liver fibrosis evaluation.
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Article Synopsis
  • The study examined the effects of a curcumin derivative called GT863 on amyotrophic lateral sclerosis (ALS), focusing on its influence on the SOD1 protein aggregation.
  • GT863 demonstrated antioxidant, anti-inflammatory, and neuroprotective properties, showing effectiveness in reducing cytotoxicity and activating protective cellular pathways in both cell-free and cultured cell experiments.
  • In tests on H46R mutant SOD1 transgenic mice, GT863 significantly slowed motor dysfunction and reduced harmful SOD1 aggregation, suggesting it could be a promising treatment for ALS.
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We previously generated an ischemic stroke in a zebrafish model using N gas perfusion; however, this model was an unsuitable drug screening system due to low throughput. In this study, we examined a zebrafish ischemic stroke model using an oxygen absorber to assess drug effects. Hypoxic exposure more than 2 h using the oxygen absorber significantly induced cell death in the brain and damage to the neuronal cells.

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Brain inflammation is a pathological characteristic of neurodegenerative diseases. In this condition, excessively activated microglia elevate proinflammatory mediator levels. We previously reported that panaxytriol inhibited lipopolysaccharide (LPS)-induced microglia activation in vitro.

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Cerebral infarct is caused by cerebrovascular occlusion and results in brain damage. Although many rodent models of cerebral infarct exist, there is none based on zebrafish. In this study, we developed a novel ischemia-reperfusion model induced by hypoxic treatment using zebrafish.

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Activated microglia induce brain inflammation and neuronal death. Panaxytriol, ((3R,9R,10R)-Heptadec-1-en-4,6-diyne-3,9,10-triol), is a component of Panax ginseng C. A.

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The toxic conformer of the 40- or 42-mer-amyloid β-proteins (Aβ) (Aβ40, Aβ42) with a turn at positions 22 and 23 plays a role in oligomer formation, leading to neurotoxicity as part of the pathogenesis of Alzheimer's disease (AD). A deletion mutant at Glu22 (E22Δ) of Aβ, known as an Osaka mutation, accelerates oligomerization. Although E22Δ-Aβ has not been found to be toxic to cultured neuronal cells and is instead synaptotoxic in long-term potentiation, there is no information on the toxic conformer of E22Δ-Aβ in AD.

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Parkinson disease (PD) is a neurodegenerative disorder characterized by a selective loss of dopaminergic neurons in the substantia nigra, and oxidative stress is thought to contribute to this pathogenesis. The nuclear factor erythroid 2-related factor 2 (Nrf2)-antioxidant response element (ARE) pathway, which induces the production of antioxidant enzymes, is thereby a potential target for therapeutics to reduce neurodegeneration in PD. Previously, we identified TPNA10168 from a chemical library as an activator of the Nrf2-ARE pathway, and the present study examined the effects of TPNA10168 on an in vivo PD model.

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