• Archives of Pharmacal Research
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• v.22 no.5
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• pp.437-447
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• 1999

Type I diabetes, also known as insulin-dependent diabetes mellitus (IDDM) results from the destruction of insulin-producing pancreatic $\beta$ cells by a progressive $\beta$ cell-specific autoimmune process. The pathogenesis of autoimmune IDDM has been extensively studied for the past two decades using animal models such as the non-obese diabetic (NOD) mouse and the Bio-Breeding (BB) rat. However, the initial events that trigger the immune responses leading to the selective destruction of the $\beta$ cells are poorly understood. It is thought that $\beta$ cell auto-antigens are involved in the triggering of $\beta$ cell-specific autoimmunity. Among a dozen putative $\beta$ cell autoantigens, glutamic acid decarboxylase (GAD) has bee proposed as perhaps the strongest candidate in both humans and the NOD mouse. In the NOD mouse, GAD, as compared with other $\beta$ cell autoantigens, provokes the earliest T cell proliferative response. The suppression of GAD expression in the $\beta$ cells results in the prevention of autoimmune diabetes in NOD mice. In addition, the major populations of cells infiltrating the iselts during the early stage of insulitis in BB rats and NOD mice are macrophages and dendritic cells. The inactivation of macrophages in NOD mice results in the prevention of T cell mediated autoimmune diabetes. Macrophages are primary contributors to the creation of the immune environment conducive to the development and activation of $\beta$cell-specific Th1-type CD4+ T cells and CD8+ cytotoxic T cells that cause autoimmune diabetes in NOD mice. CD4+ and CD8+ T cells are both believed to be important for the destruction of $\beta$ cells. These cells, as final effectors, can kill the insulin-producing $\beta$ cells by the induction of apoptosis. In addition, CD8+ cytotoxic T cells release granzyme and cytolysin (perforin), which are also toxic to $\beta$ cells. In this way, macrophages, CD4+ T cells and CD8+ T cells act synergistically to kill the $\beta$ cells in conjunction with $\beta$ cell autoantigens and MHC class I and II antigens, resulting in the onset of autoimmune type I diabetes.

• Journal of Microbiology and Biotechnology
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• v.34 no.4
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• pp.911-919
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• 2024

Solar UVB irradiation cause skin photoaging by inducing the high expression of matrix metalloproteinase (MMPs) to inhibit the expression of Type1 procollagen synthesis. 1-Kestose, a natural trisaccharide, has been indicated to show a cytoprotective role in UVB radiation-induced-HaCaT cells. However, few studies have confirmed the anti-aging effects. In the present study, we evaluated the anti-photoaging and pathological mechanism of 1-kestose using Human keratinocytes (HaCaT) cells. The results found that 1-kestose pretreatment remarkably reduced UVB-generated reactive oxygen species (ROS) accumulation in HaCaT cells. 1-Kestose suppressed UVB radiation-induced MMPs expressions by blocking MAPK/AP-1 and NF-κB p65 translocation. 1-Kestose pretreatment increased Type 1 procollagen gene expression levels by activating TGF-β/Smad signaling pathway. Taken together, our results demonstrate that 1-kestose may serve as a potent natural trisaccharide for inflammation and photoaging prevention.

• Imaging Science in Dentistry
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• v.39 no.3
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• pp.121-132
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• 2009

Purpose : To investigate the effects of 2-deoxy-D-glucose (2-DG) and quercetin (QCT) on gene expression of bone sialoprotein (BSP) and osteocalcin (OC) during the differentiation in irradiated MC3T3-E1 osteoblastic cells. Materials and Methods : When MC3T3-E1 osteoblastic cells had reached 70-80% confluence, cultures were transferred to a differentiating medium supplemented with 5 mM 2-DG or $10{\mu}M$ QCT, and then irradiated with 2, 4, 6, and 8 Gy. At various times after irradiation, the cells were analyzed for the synthesis of type I collagen, and expression of BSP and OC. Results : The synthesis of type I collagen in cells exposed to 2 Gy of radiation in the presence of 2-DG or QCT showed no significant difference compared with the control group within 15 days post-irradiation. When the cells were irradiated with 8 Gy, 2-DG facilitated the irradiation mediated decrease of type I collagen synthesis, whereas such decrease was inhibited by treating with QCT. During MC3T3-E1 osteoblastic cell differentiation, the mRNA expression of BSP and OC showed the peak value at 14 days and 21 days, respectively. 2-DG or QCT treatment alone decreased the level of BSP mRNA, but increased the OC mRNA level only at early time of differentiation (day 7). In the cells irradiated with 2, 4, 8 Gy, the mRNA expression of BSP and OC decreased at 7 days after the irradiation. The cells were treated with various dose of radiation in the presence of 2-DG or QCT, the mRNA level of both BSP and OC increased although this increase was observed at low dose of radiation (2 Gy) and at the early stage of differentiation. However, when the cells were exposed to 4, 6, or 8 Gy, the increase of BSP and OC mRNAs was detected only in cells co-incubated with QCT. Conclusion : This study demonstrates that 2-DG and QCT affect differently the expression of bone formation related factors, type I collagen, BSP, and OC in the irradiated MC3T3-E1 osteoblasic cells, according to the dose of radiation and the times of differentiation. Overall, the present findings suggest that 2-DG and QCT could have the regulatory roles as radiation-sensitizer and -protector, respectively.

• Biomolecules & Therapeutics
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• v.6 no.4
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• pp.371-377
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• 1998

The aim of the present study was to investigate the effect of Palmiwon on the type 1-prediabetic models induced by streptozotocin (STZ) in RINm5F cells and HIT-T15 cells. Palmiwon increased the cell proliferation and insulin release when pre- and post-treated for the STZ-exposed pancreatic beta cells. The cell proliferation and insulin release of these beta cells were measured by $^3$H-thymidine uptake and RIA, respectively. We also analyzed nutrients such as sugars, fatty acid and amino acids and minerals containing in Palmiwon using by gas chromatography, amino acid analyzer and AA spectrometer, respectively. Palmiwon seems to have protective and recovery properties on the prediabetic model in cellular level, which were ascribe to various nutrients and minerals containing in Palmiwon. From these results, it could be suggested that Palmiwon may be available as preventive and therapeutic prescription of type 1 diabetes mellitus.

• Molecules and Cells
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• v.47 no.2
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• pp.100031.1-100031.13
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• 2024

It is now well-accepted that obesity-induced inflammation plays an important role in the development of insulin resistance and type 2 diabetes. A key source of the inflammation is the murine epididymal and human visceral adipose tissue. The current paradigm is that obesity activates multiple proinflammatory immune cell types in adipose tissue, including adipose-tissue macrophages (ATMs), T Helper 1 (Th1) T cells, and natural killer (NK) cells, while concomitantly suppressing anti-inflammatory immune cells such as T Helper 2 (Th2) T cells and regulatory T cells (Tregs). A key feature of the current paradigm is that obesity induces the anti-inflammatory M2 ATMs in lean adipose tissue to polarize into proinflammatory M1 ATMs. However, recent single-cell transcriptomics studies suggest that the story is much more complex. Here we describe the single-cell genomics technologies that have been developed recently and the emerging results from studies using these technologies. While further studies are needed, it is clear that ATMs are highly heterogeneous. Moreover, while a variety of ATM clusters with quite distinct features have been found to be expanded by obesity, none truly resemble classical M1 ATMs. It is likely that single-cell transcriptomics technology will further revolutionize the field, thereby promoting our understanding of ATMs, adipose-tissue inflammation, and insulin resistance and accelerating the development of therapies for type 2 diabetes.

• Journal of Periodontal and Implant Science
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• v.31 no.2
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• pp.287-298
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• 2001

Recently, many natural medicines, which have advantage of less side effects and possibility of long-term use have been studied for their capacity of anti-bacterial, anti-inflammatory and regenerative potential of periodontal tissues. Olibanum has the effects to hemostasis, analgesic and anti-inflammatory, and it also has been traditionally used as a drug for the treatment of bone disease in oriental medicine. The purpose of the present study was to investigate the effects of Olibanum extracts on the activity and differentiation of MC3T3-E1 cells, alkaline phosphatase(ALP) synthesis, formation of bone nodules and expression of type I collagen of MC3T3-E1 cells. To examine the cellular activity, MC3T3-E1 cells were cultured with ${\alpha}-MEM(control)$ and each concentration of Olibanum for 2 days and 4 days. To compare the ALP synthesis, MC3T3-E1 cells were cultured with ${\alpha}-MEM(negative\; control)$, dexamethasone(positive control), and each concentration of Olibanum for 2 days and 4 days. To compare the bone nodule formation, MC3T3-E1 ells were cultured for 21 days, and to compare the type I collagen expression, MC3T3-E1 cells were cultured for 4 days. The cellular activity of MC3T3-E1 cells treated with $1{\mu}g/ml$ of Olibanum extracts was significantly increased at 4-day(p<0.05) to control. The activity of ALP in MC3T3-E1 cells treated with $1{\mu}g/ml$ Olibanum extracts was significantly increased at 4-day(p<0.05). All the experimental groups showed much more bone nodule formation than control groups. The group treated with $1{\mu}g/ml$ of Olibanum extracts was the highest bone nodule formation, and showed much more type I collagen expression than negative control. These results indicate that Olibanum extracts may be considered effective in the activity and differentiation of MC3T3-E1 cells.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.6
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• pp.463-468
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• 2012

Type 1 diabetes (T1D) is caused by dysregulation of the immune system in the pancreatic islets, which eventually leads to insulin-producing pancreatic ${\beta}$-cell death and destabilization of glucose homeostasis. One of the major characteristics of T1D pathogenesis is the production of inflammatory mediators by macrophages that result in destruction or damage of pancreatic ${\beta}$-cells. In this study the inflammatory microenvironment of T1D was simulated with RAW264.7 cells and MIN6 cells, acting as macrophages and pancreatic ${\beta}$-cells respectably. In this setting, peroxiredoxin-1, an anti-oxidant enzyme was knocked down to observe its functions in the pathogenesis of T1D. RAW264.7 cells were primed with lipopolysaccharide and co-cultured with MIN6 cells while PRX-1 was knocked down in one or both cell types. Our results suggest that hindrance of PRX-1 activity or the deficiency of this enzyme in inflammatory conditions negatively affects pancreatic ${\beta}$-cell survival. The observed decrease in viability of MIN6 cells seems to be caused by nitric oxide production. Additionally, it seems that PRX-1 affects previously reported protective activity of IL-6 in pancreatic ${\beta}$ cells as well. These results signify new, undiscovered roles for PRX-1 in inflammatory conditions and may contribute toward our understanding of autoimmunity.

• IMMUNE NETWORK
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• v.21 no.5
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• pp.33.1-33.19
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• 2021

IL-1β plays critical roles in the priming and effector phases of immune responses such as the differentiation, commitment, and memory formation of T cells. In this context, several reports have suggested that the IL-1β signal is crucial for CTL-mediated immune responses to viral infections and tumors. However, little is known regarding whether IL-1β acts directly on CD8⁺ T cells and what the molecular mechanisms underlying expression of IL-1 receptors (IL-1Rs) on CD8⁺ T cells and features of IL-1R⁺ CD8⁺ T cells are. Here, we provide evidence that the expression of IL-1R type I (IL-1RI), the functional receptor of IL-1β, is preferentially induced by IL-21 on TCR-stimulated CD8⁺ T cells. Further, IL-1β enhances the effector function of CD8⁺ T cells expressing IL-21-induced IL-1RI by increasing cytokine production and release of cytotoxic granules containing granzyme B. The IL-21-IL-1RI-IL-1β axis is involved in an augmented effector function through regulation of transcription factors BATF, Blimp-1, and IRF4. Moreover, this axis confers a unique effector function to CD8⁺ T cells compared to conventional type 1 cytotoxic T cells differentiated with IL-12. Chemical inhibitor and immunoprecipitation assay demonstrated that IL-21 induces a unique pattern of STAT activation with the formation of both STAT1:STAT3 and STAT3:STAT5 heterodimers, which are critical for the induction of IL-1RI on TCR-stimulated CD8⁺ T cells. Taken together, we propose that induction of a novel subset of IL-1RI-expressing CD8⁺ T cells by IL-21 may be beneficial to the protective immune response against viral infections and is therefore important to consider for vaccine design.

• BMB Reports
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• v.51 no.5
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• pp.207-208
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• 2018

Chitinase-Like Proteins (CLPs) are an evolutionarily conserved protein which lose their enzymatic activity for degrading chitin macromolecules. Chitinase-3-like-1 (Chi3l1) is a type of CLP that is highly expressed in epithelial cells, macrophages, etc., and is known to have correlations with type 2 inflammation and cancer. Although the increased level of Chi3l1 in the blood was reported in various disease patients, the function of Chi3l1 in adaptive immunity has been totally unknown. Recently, we found that Chi3l1 is expressed in T cells and has a negative regulatory role in T-cell activation and proliferation. A genetic ablation study of Chi3l1 in T cells showed hyperresponsiveness to TcR stimulation, which increased proliferation and Th1 differentiation. A significant increase of $IFN{\gamma}$ signaling in Chi3l1-deficient T cells synergistically increased Th1 and CTL functions against melanoma cells in vitro and in vivo. In addition, targeted knockdown by Chi3l1 siRNA complexed with the cell-penetrating peptide dNP2, which showed decreased pulmonary melanoma metastasis with increased infiltration of Th1 and CTL in the lung. This study first suggests that Chi3l1 is a novel regulator of Th1/CTL responses and could be a target for treating cancer to increase tumor immunity.

• IMMUNE NETWORK
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• v.13 no.5
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• pp.194-198
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• 2013

Recent papers have shown that the initial event in the pathogenesis of autoimmune type 1 diabetes (T1D) comprises sensing of molecular patterns released from apoptotic ${\beta}$-cells by innate immune receptors such as toll-like receptor (TLR). We have reported that apoptotic ${\beta}$-cells undergoing secondary necrosis called 'late apoptotic' ${\beta}$-cells stimulate dendritic cells (DCs) and induce diabetogenic T cell priming through TLR2. The role of other innate immune receptors such as TLR7 or TLR9 in the initiation of T1D has also been suggested. We hypothesized that TLR2 blockade could inhibit T1D at the initial step of T1D. Indeed, when a TLR2 agonist, $Pam3CSK_4$ was administered chronically, the development of T1D in nonobese diabetic (NOD) mice was inhibited. Diabetogenic T cell priming by DCs was attenuated by chronic treatment with $Pam3CSK_4$, indicating DC tolerance. For the treatment of established T1D, immune tolerance alone is not enough because ${\beta}$-cell mass is critically reduced. We employed TLR2 tolerance in conjunction with islet transplantation, which led to reversal of newly established T1D. Dipeptidyl peptidase 4 (DPP4) inhibitors are a new class of anti-diabetic agents that have beneficial effects on ${\beta}$-cells. We investigated whether a combination of DPP4 inhibition and TLR2 tolerization could reverse newly established T1D without islet transplantation. We could achieve normoglycemia by TLR2 tolerization in combination with DPP4 inhibition but not by TLR2 tolerization or DPP4 inhibition alone. ${\beta}$-cell mass was significantly increased by combined treatment with TLR2 tolerization and DPP4 inhibition. These results suggest the possibility that a novel strategy of TLR tolerization will be available for the inhibition or treatment of established T1D when combined with measures increasing critically reduced ${\beta}$-cell mass of T1D patients such as DPP4 inhibition or stem cell technology.