1.Memantine Attenuates Salicylate-induced Tinnitus Possibly by Reducing NR2B Expression in Auditory Cortex of Rat
Chul Ho JANG ; Sueun LEE ; Il Yong PARK ; Anji SONG ; Changjong MOON ; Goang Won CHO
Experimental Neurobiology 2019;28(4):495-503
Memantine, a noncompetitive antagonist of the N-methyl-d-aspartate (NMDA) receptor, suppresses the release of excessive levels of glutamate that may induce neuronal excitation. Here we investigated the effects of memantine on salicylate-induced tinnitus model. The expressions of the activity-regulated cytoskeleton-associated protein (ARC) and tumor necrosis factor-alpha (TNF α)genes; as well as the NMDA receptor subunit 2B (NR2B) gene and protein, were examined in the SH-SY5Y cells and the animal model. We also used gap-prepulse inhibition of the acoustic startle reflex (GPIAS) and noise burst prepulse inhibition of acoustic startle, and the auditory brainstem level (electrophysiological recordings of auditory brainstem responses, ABR) and NR2B expression level in the auditory cortex to evaluate whether memantine could reduce salicylate-mediated behavioral disturbances. NR2B was significantly upregulated in salicylate-treated cells, but downregulated after memantine treatment. Similarly, expression of the inflammatory cytokine genes TNFα and immediate-early gene ARC was significantly increased in the salicylate-treated cells, and decreased when the cells were treated with memantine. These results were confirmed by NR2B immunocytochemistry. GPIAS was attenuated to a significantly lesser extent in rats treated with a combination of salicylate and memantine than in those treated with salicylate only. The mean ABR threshold in both groups was not significant different before and 1 day after the end of treatment. Additionally, NR2B protein expression in the auditory cortex was markedly increased in the salicylate-treated group, whereas it was reduced in the memantine-treated group. These results indicate that memantine is useful for the treatment of salicylate-induced tinnitus.
Acoustics
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Animals
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Auditory Cortex
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Brain Stem
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Evoked Potentials, Auditory, Brain Stem
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Genes, Immediate-Early
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Glutamic Acid
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Immunohistochemistry
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Integrin alpha2
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Memantine
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Models, Animal
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N-Methylaspartate
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Neurons
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Noise
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Prepulse Inhibition
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Rats
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Reflex, Startle
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Tinnitus
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Tumor Necrosis Factor-alpha
2.Single dose oral toxicity study of a water extract of Gekko gecko in Sprague-Dawley rats
Byung-Suk JEON ; Hyeon Hwa NAM ; Huiyeong JEONG ; Joong-Sun KIM ; Sueun LEE ; Ji Hye LEE ; Yun-Soo SEO
Journal of Biomedical and Translational Research 2024;25(2):69-77
Traditional medicine and herbal remedies are gaining popularity worldwide, comprising a significant portion of healthcare research, advancements, and market demand. Growing scientif-ic evidence supports their substantial efficacy as pharmaceutical ingredients and dietary sup-plements in preventive healthcare. When developing pharmaceuticals, it is crucial to ensure that ingredients are free from side effects and toxicity in order to prioritize safety. Geckos, known as shou gong, are a diverse group of lizards that are widely utilized for treating various diseases in Korean Medicine. This study was conducted to assess the potential acute toxicity of a water extract Gekko gecko by a single oral dose in Sprague-Dawley rats. Twenty rats of each sex were randomly assigned to four groups (5 rats each). Test articles were administrat-ed once by oral gavage to rats at dose levels of 0, 500, 1,000, or 2,000 mg/kg body weight. Mortality, changes of body weight, and clinical signs of gross observation were monitored for 14 days after dosing. At the end of a 14-day observation period, all animals were sacrificed and complete macroscopic and hematological examinations were performed. There was no dead animal or test article-related effect on clinical signs, body weight, or gross finding. Other specific changes were not found between control and treated groups in hematology. Results showed no adverse effect at a dose of 500, 1,000, or 2,000 mg/kg in rats. The minimal lethal dose was considered to be over 2,000 mg/kg body weight in rats.
3.Single dose oral toxicity study of a water extract of Gekko gecko in Sprague-Dawley rats
Byung-Suk JEON ; Hyeon Hwa NAM ; Huiyeong JEONG ; Joong-Sun KIM ; Sueun LEE ; Ji Hye LEE ; Yun-Soo SEO
Journal of Biomedical and Translational Research 2024;25(2):69-77
Traditional medicine and herbal remedies are gaining popularity worldwide, comprising a significant portion of healthcare research, advancements, and market demand. Growing scientif-ic evidence supports their substantial efficacy as pharmaceutical ingredients and dietary sup-plements in preventive healthcare. When developing pharmaceuticals, it is crucial to ensure that ingredients are free from side effects and toxicity in order to prioritize safety. Geckos, known as shou gong, are a diverse group of lizards that are widely utilized for treating various diseases in Korean Medicine. This study was conducted to assess the potential acute toxicity of a water extract Gekko gecko by a single oral dose in Sprague-Dawley rats. Twenty rats of each sex were randomly assigned to four groups (5 rats each). Test articles were administrat-ed once by oral gavage to rats at dose levels of 0, 500, 1,000, or 2,000 mg/kg body weight. Mortality, changes of body weight, and clinical signs of gross observation were monitored for 14 days after dosing. At the end of a 14-day observation period, all animals were sacrificed and complete macroscopic and hematological examinations were performed. There was no dead animal or test article-related effect on clinical signs, body weight, or gross finding. Other specific changes were not found between control and treated groups in hematology. Results showed no adverse effect at a dose of 500, 1,000, or 2,000 mg/kg in rats. The minimal lethal dose was considered to be over 2,000 mg/kg body weight in rats.
4.Single dose oral toxicity study of a water extract of Gekko gecko in Sprague-Dawley rats
Byung-Suk JEON ; Hyeon Hwa NAM ; Huiyeong JEONG ; Joong-Sun KIM ; Sueun LEE ; Ji Hye LEE ; Yun-Soo SEO
Journal of Biomedical and Translational Research 2024;25(2):69-77
Traditional medicine and herbal remedies are gaining popularity worldwide, comprising a significant portion of healthcare research, advancements, and market demand. Growing scientif-ic evidence supports their substantial efficacy as pharmaceutical ingredients and dietary sup-plements in preventive healthcare. When developing pharmaceuticals, it is crucial to ensure that ingredients are free from side effects and toxicity in order to prioritize safety. Geckos, known as shou gong, are a diverse group of lizards that are widely utilized for treating various diseases in Korean Medicine. This study was conducted to assess the potential acute toxicity of a water extract Gekko gecko by a single oral dose in Sprague-Dawley rats. Twenty rats of each sex were randomly assigned to four groups (5 rats each). Test articles were administrat-ed once by oral gavage to rats at dose levels of 0, 500, 1,000, or 2,000 mg/kg body weight. Mortality, changes of body weight, and clinical signs of gross observation were monitored for 14 days after dosing. At the end of a 14-day observation period, all animals were sacrificed and complete macroscopic and hematological examinations were performed. There was no dead animal or test article-related effect on clinical signs, body weight, or gross finding. Other specific changes were not found between control and treated groups in hematology. Results showed no adverse effect at a dose of 500, 1,000, or 2,000 mg/kg in rats. The minimal lethal dose was considered to be over 2,000 mg/kg body weight in rats.
5.Single dose oral toxicity study of a water extract of Gekko gecko in Sprague-Dawley rats
Byung-Suk JEON ; Hyeon Hwa NAM ; Huiyeong JEONG ; Joong-Sun KIM ; Sueun LEE ; Ji Hye LEE ; Yun-Soo SEO
Journal of Biomedical and Translational Research 2024;25(2):69-77
Traditional medicine and herbal remedies are gaining popularity worldwide, comprising a significant portion of healthcare research, advancements, and market demand. Growing scientif-ic evidence supports their substantial efficacy as pharmaceutical ingredients and dietary sup-plements in preventive healthcare. When developing pharmaceuticals, it is crucial to ensure that ingredients are free from side effects and toxicity in order to prioritize safety. Geckos, known as shou gong, are a diverse group of lizards that are widely utilized for treating various diseases in Korean Medicine. This study was conducted to assess the potential acute toxicity of a water extract Gekko gecko by a single oral dose in Sprague-Dawley rats. Twenty rats of each sex were randomly assigned to four groups (5 rats each). Test articles were administrat-ed once by oral gavage to rats at dose levels of 0, 500, 1,000, or 2,000 mg/kg body weight. Mortality, changes of body weight, and clinical signs of gross observation were monitored for 14 days after dosing. At the end of a 14-day observation period, all animals were sacrificed and complete macroscopic and hematological examinations were performed. There was no dead animal or test article-related effect on clinical signs, body weight, or gross finding. Other specific changes were not found between control and treated groups in hematology. Results showed no adverse effect at a dose of 500, 1,000, or 2,000 mg/kg in rats. The minimal lethal dose was considered to be over 2,000 mg/kg body weight in rats.
6.CCCTC-binding factor is essential to the maintenance and quiescence of hematopoietic stem cells in mice.
Tae Gyun KIM ; Sueun KIM ; Soyeon JUNG ; Mikyoung KIM ; Bobae YANG ; Min Geol LEE ; Hyoung Pyo KIM
Experimental & Molecular Medicine 2017;49(8):e371-
Hematopoiesis involves a series of lineage differentiation programs initiated in hematopoietic stem cells (HSCs) found in bone marrow (BM). To ensure lifelong hematopoiesis, various molecular mechanisms are needed to maintain the HSC pool. CCCTC-binding factor (CTCF) is a DNA-binding, zinc-finger protein that regulates the expression of its target gene by organizing higher order chromatin structures. Currently, the role of CTCF in controlling HSC homeostasis is unknown. Using a tamoxifen-inducible CTCF conditional knockout mouse system, we aimed to determine whether CTCF regulates the homeostatic maintenance of HSCs. In adult mice, acute systemic CTCF ablation led to severe BM failure and the rapid shrinkage of multiple c-Kit(hi) progenitor populations, including Sca-1⁺ HSCs. Similarly, hematopoietic system-confined CTCF depletion caused an acute loss of HSCs and highly increased mortality. Mixed BM chimeras reconstituted with supporting BM demonstrated that CTCF deficiency-mediated HSC depletion has both cell-extrinsic and cell-intrinsic effects. Although c-Kit(hi) myeloid progenitor cell populations were severely reduced after ablating Ctcf, c-Kit(int) common lymphoid progenitors and their progenies were less affected by the lack of CTCF. Whole-transcriptome microarray and cell cycle analyses indicated that CTCF deficiency results in the enhanced expression of the cell cycle-promoting program, and that CTCF-depleted HSCs express higher levels of reactive oxygen species (ROS). Importantly, in vivo treatment with an antioxidant partially rescued c-Kit(hi) cell populations and their quiescence. Altogether, our results suggest that CTCF is indispensable for maintaining adult HSC pools, likely by regulating ROS-dependent HSC quiescence.
Adult
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Animals
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Bone Marrow
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Cell Cycle
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Chimera
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Chromatin
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Fibrinogen*
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Hematopoiesis
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Hematopoietic Stem Cells*
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Homeostasis
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Humans
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Lymphoid Progenitor Cells
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Mice*
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Mice, Knockout
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Mortality
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Myeloid Progenitor Cells
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Reactive Oxygen Species
7.Chronic Treatment with Combined Chemotherapeutic Agents Affects Hippocampal Micromorphometry and Function in Mice, Independently of Neuroinflammation.
Sohi KANG ; Sueun LEE ; Juhwan KIM ; Jong Choon KIM ; Sung Ho KIM ; Yeonghoon SON ; Taekyun SHIN ; BuHyun YOUN ; Joong Sun KIM ; Hongbing WANG ; Miyoung YANG ; Changjong MOON
Experimental Neurobiology 2018;27(5):419-436
Chemotherapeutic agents induce long-term side effects, including cognitive impairment and mood disorders, particularly in breast cancer survivors who have undergone chemotherapy. However, the precise mechanisms underpinning chemotherapy-induced hippocampal dysfunction remain unknown. In this study, we investigated the detrimental effects of chronic treatment with a combination of adriamycin and cyclophosphamide (AC) on the neuronal architecture and functions of the hippocampi of female C57BL/6 mice. After chronic AC administration, mice showed memory impairment (measured using a novel object recognition memory task) and depression-like behavior (measured using the tail suspension test and forced swim test). According to Golgi staining, chronic AC treatment significantly reduced the total dendritic length, ramification, and complexity as well as spine density and maturation in hippocampal neurons in a sub-region-specific manner. Additionally, the AC combination significantly reduced adult neurogenesis, the extent of the vascular network, and the levels of hippocampal angiogenesis-related factors. However, chronic AC treatment did not increase the levels of inflammation-related signals (microglial or astrocytic distribution, or the levels of pro-inflammatory cytokines or M1/M2 macrophage markers). Thus, chronic AC treatment changed the neuronal architecture of the adult hippocampus, possibly by reducing neurogenesis and the extent of the vasculature, independently of neuroinflammation. Such detrimental changes in micromorphometric parameters may explain the hippocampal dysfunction observed after cancer chemotherapy.
Adult
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Animals
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Breast Neoplasms
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Cognition Disorders
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Cyclophosphamide
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Cytokines
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Doxorubicin
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Drug Therapy
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Female
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Hindlimb Suspension
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Hippocampus
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Humans
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Macrophages
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Memory
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Mice*
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Mood Disorders
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Neurogenesis
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Neurons
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Spine
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Survivors