Publications by authors named "Nae Dun"

Background: Acupuncture or electroacupuncture (EA) appears to be a potential treatment in acute clinical traumatic brain injury (TBI); however, it remains uncertain whether acupuncture affects post-TBI histone deacetylase (HDAC) expression or impacts other biochemical/neurobiological events.

Materials And Methods: We used behavioral testing, Western blot, and immunohistochemistry analysis to evaluate the cellular and molecular effects of EA at LI4 and LI11 in both weight drop-impact acceleration (WD)- and controlled cortical impact (CCI)-induced TBI models.

Results: Both WD- and CCI-induced TBI caused behavioral dysfunction, increased cortical levels of HDAC1 and HDAC3 isoforms, activated microglia and astrocytes, and decreased cortical levels of BDNF as well as its downstream mediators phosphorylated-Akt and phosphorylated-GSK-3β.

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Antipruritic effects of kappa opioid receptor (KOR) agonists have been shown in rodent models of acute and chronic scratching (itchlike behavior). Three KOR agonists, nalfurafine, difelikefalin, and nalbuphine, are in clinical studies for antipruritic effects in chronic itch of systemic and skin diseases. Nalfurafine (in Japan) and difelikefalin (in the USA) were approved to be used in the treatment of chronic itch in hemodialysis patients.

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Chronic itch is one of the disturbing symptoms of inflammatory skin diseases. Kappa opioid receptor agonists are effective in suppressing scratching in mice against different pruritogens. Nalbuphine, a nonscheduled kappa opioid receptor agonist and mu opioid receptor antagonist, has been in clinical use for post-operative pain management since the 1980s and recently has been in clinical trials for chronic itch of prurigo nodularis (https://www.

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Copper deficiency (hypocupremia) or toxicosis (hypercupremia) may cause disorders of central and peripheral nervous systems. Hypocupremia causes myeloneuropathy resembling vitamin B12 deficiency. However, the clinical manifestations, particularly peripheral neuropathy (PN), of hypercupremia have not been adequately evaluated.

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Visual Evoked Potential (VEP) is a useful tool in identifying abnormality relative to the integration of optic pathways, and aids the diagnosis of central nervous system demyelinating disorders, such as multiple sclerosis (MS). However, the sensitivity of VEP in detecting early optic abnormality as a visual function surrogate remains questionable. Recent studies showed that low-contrast VEP increases sensitivity in early detection of optic demyelination.

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In this brief review we summarize the current fndings relative to the discovery of a small peptide ligand, phoenixin (PNX). Using a bioinformatic approach, two novel peptides PNX-14 and PNX-20 containing 14 and 20 amino acids, respectively, were isolated from diverse tissues including the brain, heart, lung and stomach. Mass spectrometry analysis identified a major and minor peak corresponding to PNX-14 and PNX-20, in rat or mouse spinal cord extracts.

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This study tested the hypothesis that repetitive scratching provoked by two known pruritogens, compound 48/80 and 5'-guanidinonaltrindole (GNTI), is accompanied by activation of microglial cells in the mouse spinal cord. Immunohistochemical studies revealed that the complement receptor 3, also known as cluster determinant 11b (CD11b), a cell surface marker of microglial cells, was upregulated in the spinal cord 10-30 min after a subcutaneous (s.c.

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Tight control of glucose excursions has been a long-standing goal of treatment for patients with type 2 diabetes mellitus in order to ameliorate the morbidity and mortality associated with hyperglycemia. Fibroblast growth factor (FGF) 19 is a hormone-like enterokine released postprandially that emerged as a potential therapeutic agent for metabolic disorders, including diabetes and obesity. Remarkably, FGF19 treatment has hypoglycemic actions that remain potent in models of genetic and acquired insulin resistance.

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The present study was undertaken to investigate the influence of electroacupuncture (EA) on compulsive scratching in mice and c-Fos expression elicited by subcutaneous (s.c.) administration of a known puritogen, 5'-guanidinonaltrindole (GNTI) to the neck.

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Angiotensin-(1-12) [Ang-(1-12)], a newer member of angiotensin peptides, is proposed to be converted enzymatically to angiotensin I (Ang I) and to angiotensin II (Ang II); the latter being the bioactive peptide. We studied the Ang-(1-12) and Ang II responses in COS-7 cells or CHO cells transfected with 5 μg AT1R by monitoring [Ca(2+)]i using the Fluo-4. Ang II (1 pM-1 μM) and Ang-(1-12) (5 pM-5 μM) increased [Ca(2+)]i with an EC50 of 0.

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pRb is frequently inactivated in tumours by mutations or phosphorylation. Here, we investigated whether pRb plays a role in obesity. The Arcuate nucleus (ARC) in hypothalamus contains antagonizing POMC and AGRP/NPY neurons for negative and positive energy balance, respectively.

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The utility of PSVue 794 (PS794), a near-infrared fluorescent dye conjugated to a bis[zinc (II)-dipicolylamine] (Zn-DPA) targeting moiety, in imaging brain infarct was assessed in a rat middle cerebral artery occlusion-reperfusion model. Following reperfusion, 1 mM PS794 solution was administered intravenously via a tail vein. Fluorescence images were captured between 6 to 72 hours postinjection using a LI-COR Biosciences Pearl Imaging System.

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Unlabelled: Human and animal studies suggest that estrogens are involved in the processing of nociceptive sensory information and analgesic responses in the central nervous system. Rapid pronociceptive estrogenic effects have been reported, some of which likely involve G protein-coupled estrogen receptor (GPER) activation. Membrane depolarization and increases in cytosolic calcium and reactive oxygen species (ROS) levels are markers of neuronal activation, underlying pain sensitization in the spinal cord.

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Leptin and melanocortin signaling control ingestive behavior, energy balance, and substrate utilization, but only leptin signaling defects cause hypothalamic hypogonadism and infertility. Although GnRH neurons do not express leptin receptors, leptin influences GnRH neuron activity via regulation of immediate downstream mediators including the neuropeptides neuropeptide Y and the melanocortin agonist and antagonist, α-MSH, agouti-related peptide, respectively. Here we show that modulation of melanocortin signaling in female db/db mice through ablation of agouti-related peptide, or heterozygosity of melanocortin 4 receptor, restores the timing of pubertal onset, fertility, and lactation.

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Background: Buprenorphine is an opioid receptor ligand whose mechanism of action is incompletely understood.

Methods: Using Ca(2+) imaging, we assessed the effects of buprenorphine, β-endorphin, and morphine on cytosolic Ca(2+) concentration [Ca(2+)](i), in rat striatal neurons.

Results: Buprenorphine (0.

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Gastrin-releasing peptide (GRP) has been implicated in the itch-scratch cycle. We investigated if this gut-brain-skin peptide plays a role in the compulsive, hindleg scratching of the neck of mice by 5'-guanidinonaltrindole (GNTI), the kappa opioid receptor antagonist, and in the antipruritic activity of nalfurafine, the kappa opioid agonist. Previously, we showed that GNTI (0.

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Accumulating evidence implicates nicotinic acid adenine dinucleotide phosphate (NAADP) in the control of Ca(2+)-dependent functions. Little, however, is known concerning its role in the vascular endothelium, a major regulator of blood pressure. Here, we show that NAADP acetoxymethyl ester (NAADP-AM), a cell-permeant NAADP analog, increases cytosolic Ca(2+) concentration in aortic endothelial cells.

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Understanding of calcium signaling pathways in cells is essential for elucidating the mechanisms of both normal cell function and cancer development. Calcium messengers play the crucial role for intracellular Ca(2+) release. We propose a new approach to detecting the calcium second messenger nicotinic acid adenine dinucleotide phosphate (NAADP) in cell extracts using surface-enhanced Raman spectroscopy (SERS).

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The G protein-coupled receptor GPR30 binds 17beta-estradiol (E(2)) yet differs from classic estrogen receptors (ERalpha and ERbeta). GPR30 can mediate E(2)-induced nongenomic signaling, but its role in ERalpha-positive breast cancer remains unclear. Gene expression microarray data from five cohorts comprising 1,250 breast carcinomas showed an association between increased GPR30 expression and ERalpha-positive status.

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Nicotinic acid adenine dinucleotide phosphate (NAADP) is a potent and widespread calcium-mobilizing messenger, the properties of which have been most extensively described in sea urchin eggs. The molecular basis for calcium release by NAADP, however, is not clear and subject to controversy. Recent studies have provided evidence that members of the two-pore channel (TPC) family in mammals are the long sought after target channels for NAADP.

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Nicotinic acid adenine dinucleotide phosphate (NAADP) is a widespread and potent calcium-mobilizing messenger that is highly unusual in activating calcium channels located on acidic stores. However, the molecular identity of the target protein is unclear. In this study, we show that the previously uncharacterized human two-pore channels (TPC1 and TPC2) are endolysosomal proteins, that NAADP-mediated calcium signals are enhanced by overexpression of TPC1 and attenuated after knockdown of TPC1, and that mutation of a single highly conserved residue within a putative pore region abrogated calcium release by NAADP.

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The aim of this study was to establish the effect of lidocaine, a local anesthetic, on pain and itch using formalin-induced nociception and kappa opioid antagonist-induced scratching models in mice. We investigated if local intradermal pretreatment (at -10 min) with lidocaine N-ethyl bromide (lidocaine, 2%, 0.1 ml) antagonizes behavioral responses and prevents c-fos expression induced by pain and itch.

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NAADP (nicotinic acid-adenine dinucleotide phosphate) is an unusual second messenger thought to mobilize acidic Ca(2+) stores, such as lysosomes or lysosome-like organelles, that are functionally coupled to the ER (endoplasmic reticulum). Although NAADP-sensitive Ca(2+) stores have been described in neurons, the physiological cues that recruit them are not known. Here we show that in both hippocampal neurons and glia, extracellular application of glutamate, in the absence of external Ca(2+), evoked cytosolic Ca(2+) signals that were inhibited by preventing organelle acidification or following osmotic bursting of lysosomes.

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