• Molecules and Cells
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• v.40 no.4
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• pp.254-261
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• 2017

Glioblastomas (GBM) are very difficult to treat and their aggressiveness is one of the main reasons for this as well as for the frequent recurrences. MicroRNAs post-transcriptionally regulate their target genes through interaction between their seed sequence and 3'UTR of the target mRNAs. We previously reported that miR-296-3p is regulated by neurofibromatosis 2 (NF2) and enhances the invasiveness of GBM cells via SOCS2/STAT3. In this study, we investigated whether miR-296-5p, which originates from the same precursor miRNA as miR-296-3p, can increase the invasiveness of GBM cells. It was observed that miR-296-5p potentiated the invasion of various GBM cells including LN229, T98G, and U87MG. Through bioinformatics approaches, two genes were identified as miR-296-5p targets: caspase-8 (CASP8) and nerve growth factor receptor (NGFR). From results obtained from Ago2 immunoprecipitation and luciferase assays, we found that miR-296-5p downregulates CASP8 and NGFR through direct interaction between seed sequence of the miRNA and 3'UTR of the target mRNA. Knockdown of CASP8 or NGFR also increased the invasive ability of GBM cells, indicating that CASP8 and NGFR are involved in potentiation of invasiveness by miR-296-5p. Consistent with our findings, CASP8 was downregulated in brain metastatic lung cancer cells, which have a high level of miR-296-5p, compared to parental cells, suggesting that miR-296-5p may be generally associated with the acquisition of invasiveness. Collectively, our results implicate miR-296-5p as a potential cause of invasiveness in cancer and suggest it as a promising therapeutic target for GBM.

• BMB Reports
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• v.57 no.4
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• pp.167-175
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• 2024

Cancer progression is driven by genetic mutations, environmental factors, and intricate interactions within the tumor microenvironment (TME). The TME comprises of diverse cell types, such as cancer cells, immune cells, stromal cells, and neuronal cells. These cells mutually influence each other through various factors, including cytokines, vascular perfusion, and matrix stiffness. In the initial or developmental stage of cancer, neurotrophic factors such as nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor are associated with poor prognosis of various cancers by communicating with cancer cells, immune cells, and peripheral nerves within the TME. Over the past decade, research has been conducted to prevent cancer growth by controlling the activation of neurotrophic factors within tumors, exhibiting a novel attemt in cancer treatment with promising results. More recently, research focusing on controlling cancer growth through regulation of the autonomic nervous system, including the sympathetic and parasympathetic nervous systems, has gained significant attention. Sympathetic signaling predominantly promotes tumor progression, while the role of parasympathetic signaling varies among different cancer types. Neurotransmitters released from these signalings can directly or indirectly affect tumor cells or immune cells within the TME. Additionally, sensory nerve significantly promotes cancer progression. In the advanced stage of cancer, cancer-associated cachexia occurs, characterized by tissue wasting and reduced quality of life. This process involves the pathways via brainstem growth and differentiation factor 15-glial cell line-derived neurotrophic factor receptor alpha-like signaling and hypothalamic proopiomelanocortin neurons. Our review highlights the critical role of neurotrophic factors as well as central nervous system on the progression of cancer, offering promising avenues for targeted therapeutic strategies.

• Journal of Ginseng Research
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• v.43 no.2
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• pp.272-281
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• 2019

Background: Diabetic sensorineural damage is a complication of the sensory neural system, resulting from long-term hyperglycemia. Red ginseng (RG) has shown efficacy for treatment of various diseases, including diabetes mellitus; however, there is little research about its benefit for treating sensorineural damage. Therefore, we aim to evaluate RG efficacy in alloxan-induced diabetic neuromast (AIDN) zebrafish. Methods: In this study, we developed and validated an AIDN zebrafish model. To assess RG effectiveness, we observed morphological changes in live neuromast zebrafish. Also, zebrafish has been observed to have an ultrastructure of hair-cell cilia under scanning electron microscopy. Thus, we recorded these physiological traits to assess hair cell function. Finally, we confirmed that RG promoted neuromast recovery via nerve growth factor signaling pathway markers. Results: First, we established an AIDN zebrafish model. Using this model, we showed via live neuromast imaging that RG fostered recovery of sensorineural damage. Damaged hair cell cilia were recovered in AIDN zebrafish. Furthermore, RG rescued damaged hair cell function through cell membrane ion balance. Conclusion: Our data suggest that RG potentially facilitates recovery in AIDN zebrafish, and its mechanism seems to be promotion of the nerve growth factor pathway through increased expression of topomyosin receptor kinase A, transient receptor potential channel vanilloid subfamily type 1, and mitogen-activated protein kinase phosphorylation.

• Journal of Periodontal and Implant Science
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• v.34 no.1
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• pp.205-221
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• 2004

Periodontal ligament(PDL) cells have been known as playing an important roles in periodontal regeneration and gingival fibroblasts are also important to periodontal regeneration by forming connective tissue attachment. There were rare studies about the gene expression patterns of PDL cells and gingival fibroblasts, therefore in this study, we tried cDNA microarray-based gene expression monitoring to explain the functional differences of PDL cells and gingival fibroblasts in vivo and to confirm the characteristics of PDL cells. Total RNA were extracted from PDL cells and gingival fibroblasts of same person and same passages, and mRNA were isolated from the total RNA using Oligotex mRNA midi kit(Qiagen) and then fluorescent cDNA probe were prepared. And microarray hybridization were performed. The gene expression patterns of PDL cells and gingival fibroblasts were quite different. About 400 genes were expressed more highly in the PDL cells than gingival fibroblasts and about 300 genes were more highly expressed in the gingival fibroblasts than PDL cells. Compared growth factor- and growth factor receptor-related gene expression patterns of PDL cells with gingival fibroblasts, IGF-2, IGF-2 associated protein, nerve growth factor, placental bone morphogenic protein, neuron-specific growth- associated protein, FGF receptor, EGF receptor-related gene and PDGF receptor were more highly expressed in the PDL cells than gingival fibroblasts. The results of collagen gene expression patterns showed that collagen type I, type III, type VI and type VII were more highly expressed in the PDL cells than gingival fibroblasts, and in the gingival fibroblasts collagen type V, XII were more highly expressed than PDL cells. The results of osteoblast-related gene expression patterns showed that osteoblast specific cysteine-rich protein were more highly expressed in the PDL cells than gingival fibroblasts. The results of cytoskeletal proteins gene expression patterns showed that a-smooth muscle actin, actin binding protein, smooth muscle myosin heavy chain homolog and myosin light chain were more highly expressed in the PDL cells than gingival fibrobalsts, and ${\beta}-actin$, actin-capping protein(${\beta}$ subunit), actin- related protein Arp3(ARP) and myosin class I(myh-1c) were more highly expressed in the gingival fibroblasts than PDL cells. Osteoprotegerin/osteoclastogenesis inhibitory factor(OPG/OCIF) was more highly expressed in the PDL cells than gingival fibroblasts. According to the results of this study, PDL cells and gingival fibroblasts were quite different gene expression patterns though they are the fibroblast which have similar shape. Therefore PDL cells & gingival fibroblasts are heterogeneous populations which represent distinct characteristics. If more studies about genes that were differently expressed in each PDL cells & gingival fibroblasts would be performed in the future, it would be expected that the characteristics of PDL cells would be more clear.

• Journal of Life Science
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• v.26 no.5
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• pp.509-518
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• 2016

Asparagus cochinchinensis is a medical plant that has long been used to treat fever, cough, kidney disease, breast cancer, inflammatory disease and brain disease in northeast Asian countries. Although several studies have been conducted on the anti-neuroinflammatory effects of A. cochinchinensis, the correlation between these effects and nerve growth factor (NGF) has not yet been examined. In this study, we investigated the effects of an aqueous extract of A. cochinchinensis (AEAC) on the secretion and action mechanism of NGF in neuronal cells. The concentration of the NGF protein in the supernatant collected from cultured cells increased significantly in B35 cells treated with AEAC in comparison with the vehicle-treated group without any specific cytotoxicity. Furthermore, the mRNA expression of NGF showed a very similar pattern to its protein concentration. To examine the bioactivity of NGF secreted from B35 cells, undifferentiated PC12 cells were cultured in an AEAC-conditioned medium and neuritic outgrowth was observed. The dendrite length of PC12 cells in the AEAC-treated group was significantly higher than that in the vehicle-treated group. Moreover, the level of the downstream effectors p-TrkA and p-ERK of the high-affinity NGF receptor was significantly higher in the AEAC-treated group, while the expression of the downstream effectors of the low-affinity NGF receptor was significantly lower in the same group. These results suggest that AEAC may contribute to the regulation of NGF expression and secretion in neuronal cells; it is therefore an excellent candidate for further investigation as a therapeutic drug for neurodegenerative diseases.

• International Journal of Oral Biology
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• v.39 no.2
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• pp.107-114
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• 2014

Taste is an important sense in survival and growth of animals. The growth and maintenance of taste buds, the receptor organs of taste sense, are under the regulation of various neurotrophic factors. But the distribution aspect of neurotrophic factors and their receptors in distinct taste cell types are not clearly known. The present research was designed to characterize mRNA expression pattern of neurotrophic factors and their receptors in distinct type of taste cells. In male 45-60 day-old Sprague-Dawley rats, epithelial tissues with and without circumvallate and folliate papillaes were dissected and homogenized, and mRNA expressions for neurotrophic factors and their receptors were determined by RT-PCR. The mRNA expressions of brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT3), receptor tyrosine kinase B (TrkB), exclusion of nerve growth factor (NGF), neurotrophin-4/5 (NT4/5), receptor tyrosine kinase A (TrkA), receptor tyrosine kinase C (TrkC), and p75NGFR were observed in some population of taste cell. In support of this result and to characterize which types of taste cells express NT3, BDNF, or TrkB, we examined mRNA expressions of NT3, BDNF, or TrkB in the $PLC{\beta}2$ (a marker of Type II cell)-and/or SNAP25 (a marker of Type III cell)-positive taste cells by a single taste cell RT-PCR and found that the ratio of positively stained cell numbers were 17.4, 6.5, 84.1, 70.3, and 1.4 % for $PLC{\beta}2$, SNAP25, NT3, BDNF, and TrkB, respectively. In addition, all of $PLC{\beta}2$-and SNAP25-positive taste cells expressed NT3 mRNA, except for one taste bud cell. The ratios of NT3 mRNA expressions were 100% and 91.7% in the SNAP25-and $PLC{\beta}2$-positive taste cells, respectively. However, two TrkB-positive taste cells co-expressed neither $PLC{\beta}2$ nor SNAP 25. The results suggest that the most of type II or type III cells express BDNF and NT3 mRNA, but the expression is shown to be less in type I taste cells.

• Biomolecules & Therapeutics
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• v.30 no.4
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• pp.360-367
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• 2022

Tropomyosin receptor kinase A (TrkA) protein is a receptor tyrosine kinase encoded by the NTRK1 gene. TrkA signaling mediates the proliferation, differentiation, and survival of neurons and other cells following stimulation by its ligand, the nerve growth factor. Chromosomal rearrangements of the NTRK1 gene result in the generation of TrkA fusion protein, which is known to cause deregulation of TrkA signaling. Targeting TrkA activity represents a promising strategy for the treatment of cancers that harbor the TrkA fusion protein. In this study, we evaluated the TrkA-inhibitory activity of the benzoxazole compound KRC-108. KRC-108 inhibited TrkA activity in an in vitro kinase assay, and suppressed the growth of KM12C colon cancer cells harboring an NTRK1 gene fusion. KRC-108 treatment induced cell cycle arrest, apoptotic cell death, and autophagy. KRC-108 suppressed the phosphorylation of downstream signaling molecules of TrkA, including Akt, phospholipase Cγ, and ERK1/2. Furthermore, KRC-108 exhibited antitumor activity in vivo in a KM12C cell xenograft model. These results indicate that KRC-108 may be a promising therapeutic agent for Trk fusion-positive cancers.

• Journal of radiological science and technology
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• v.21 no.1
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• pp.79-87
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• 1998

The total-bodies of 10 week-old Sprague-Dawley rats were irradiated with single doses 4.5 and 7.5 Gy, respectively. The effects on plasma and sciatic nerve platelet-derived growth factor(PDGF) concentrations and sciatic nerve PDGF ${\alpha}$ -and ${\beta}$ -receptors densities were examined up to 10 days post-treatment. There was no consistent significant variation in the plasma and sciatic nerve PDGF concentrations in time over the period of study between 4.5 and 7.5 Gy groups. Plasma PDGF concentrations were significantly reduced to 58% of control values between 5 and 10 days with 4.5 Gy and to 51% of control values as percentage of control values between 5 and 10 days with 7.5 Gy after irradiation, respectively(p<0.05). Sciatic nerve PDGF concentrations were increased to 118% of control values at 1 day with 4.5 Gy and to 130% of control values at 1 day with 7.5 Gy after irradiation, respectively(p>0.05). After irradiation, the levels of PDGF ${\alpha}$ -receptor protein density were reduced to 33% of control values at 2 days with 4.5 Gy and to 50% at 2 days with 7.5 Gy, while the levels of PDGF ${\beta}$-receptor protein density were reduced to maximally 26% of control values at 2 days with 4.5 Gy and to 27% at 2 days with 7.5 Gy, respectively, but both initial decreased levels of those were increased subsequently after 2 days following irradiation. These results suggest that the radiation-induced alteration of plasma and sciatic nerve PDGF concentrations, and sciatic nerve PDGF ${\alpha}$ -and ${\beta}$ -receptors densities may be involved in the pathogenesis of bone marrow stem cell and peripheral neuron damages.

• Animal Bioscience
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• v.35 no.8
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• pp.1235-1249
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• 2022

Objective: The purpose of this study was to evaluate the protection of glutamate (GLU) against the impairment in intestinal barrier function induced by lipopolysaccharide (LPS) stress in weaned pigs. Methods: Twenty-four weaned pigs were divided into four treatments containing: i) non-challenged control, ii) LPS-challenged control, iii) LPS+1.0% GLU, and iv) LPS+2.0% GLU. On day 28, pigs were treated with LPS or saline. Blood samples were collected at 0, 2, and 4 h post-injection. After blood samples collection at 4 h, all pigs were slaughtered, and spleen, mesenteric lymph nodes, liver and intestinal samples were obtained. Results: Dietary GLU supplementation inhibited the LPS-induced oxidative stress in pigs, as demonstrated by reduced malondialdehyde level and increased glutathione level in jejunum. Diets supplemented with GLU enhanced villus height, villus height/crypt depth and claudin-1 expression, attenuated intestinal histology and ultrastructure impairment induced by LPS. Moreover, GLU supplementation reversed intestinal intraepithelial lymphocyte number decrease and mast cell number increase induced by LPS stress. GLU reduced serum cortisol concentration at 4 h after LPS stress and downregulated the mRNA expression of intestinal corticotropin-releasing factor signal (corticotrophin-releasing factor [CRF], CRF receptor 1 [CRFR1], glucocorticoid receptor, tryptase, nerve growth factor, tyrosine kinase receptor A), and prevented mast cell activation. GLU upregulated the mRNA expression of intestinal transforming growth factor β. Conclusion: These findings indicate that GLU attenuates LPS-induced intestinal mucosal barrier injury, which is associated with modulating CRF signaling pathway.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05a
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• pp.110-110
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• 2002

15-Deoxy-$\Delta$12, 14-prostaglandin J2 (15-deoxy-PGJ2), a naturally occurring ligand activates the peroxisome proliferator-activated receptor-$\gamma$(PPAR-$\gamma$). It was known to have promoting ability of nerve growth factor(NGF)-induced neurite extension. However, it is not clear yet as to what signaling pathway is involved in its promoting ability of neurite extension.(omitted)