• Environmental Mutagens and Carcinogens
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• v.22 no.1
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• pp.39-46
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• 2002

Obesity is a complex metabolic disorder with a strong genetic component. There are many candidate genes for obesity and its related phenotypes. We studied genetic variations between Korean obese and lean groups. Polymorphisms investigated were the Msp I polymorphism of the $\alpha$$_{2A}$-adrenergic receptor ($\alpha$$_{2A}$-AR) gene, the Mnl I polymorphism of the $\alpha$$_2$-adrenergic receptor ($\alpha$$_2$-AR) gene, the BstO I polymorphism of the $\beta$$_3$-adrenergic receptor ($\beta$$_3$-AR) gene, the Pml I polymorphism of the lamin A/C (LMNA) gene, the Hga I polymorphism of the clearance receptor (NPRC) gene, the Msp I polymorphism of the leptin gene, BclI polymorphism of the uncoupling protein 1 (UCPI) gene and the Hha I polymorphism of the fatty acid binding protein 2 (FABP2) gene. Among these genetic markers, Pml I polymorphism at the LMNA gene and Bcl I polymorphism at the UCP1 gene were significantly associated with obesity. However, further studies are required whether thease findings are reproduced in large population, although two polymorphisms might be useful as genetic markers in the ethiology of obesity in Korean population.ion.

• Biomolecules & Therapeutics
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• v.10 no.1
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• pp.37-42
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• 2002

Brain drug targeting through the blood-brain barrier (BBB) in vivo is possible with peptidornirnetic monoclonal antibodies that undergo receptor-mediated transcytosis through the BBB. Monoclonal antibody to the rat transferrin receptor, such as the OX26 was studied in rats as a transport vector through BBB on the transferrin receptor. But, OX26 is not an effective brain delivery vector in mouse. In the present studies, rat monoclonal antibody, 8D3 to the mouse transferrin receptor were evaluated for brain drug targeting vector intransgenic mouse model. Pharrnacokinetic parameters in plasma and organ uptakes were determined at varioustimes after i.v. bolus injection of [$^{}125}I$] 8D3 in Balb/c mice. Brain uptake of [$^{}125}I$] 8D3 was also studied with an internal carotid artery perfusioncapillary depletion method. After i.v. injection of [$^{}125}I$] 8D3, plasma concentrations declined biexponentially with elimination half lift of approximately 2.2 hours. Brain uptake of [$^{}125}I$] 8D3 was $0.50{\pm}0.09$ persent of injected dose per g brain after 2 hours i.v. injection. After perfusion 5 min the apparent volume of distibution of [$^{}125}I$] 8D3 in brain was $22.3 {\mu}l/g,$ which was 4.8 fold higher than the intravascular volume. These studies indicate rat monoclonal antibody to the mouse transferrin receptor, 8D3 may be used for brain drug targeting vector in mice.

• International Journal of Oral Biology
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• v.32 no.2
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• pp.67-73
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• 2007

Periodontitis is a chronic infectious disease that leads to periodontal destruction, and is one of the major causes of tooth loss in humans. The osteoclast differentiation factor (ODF), which is also known as the receptor activator of the NF-kB ligand (RANKL), is a surface-associated ligand on bone marrow stromal cells and osteoblasts. RANKL activates its cognate receptor, RANK, on osteoclast progenitor cells, which leads to the differentiation of mononucleated precursor cells. Osteoprotegerin (OPG) is a decoy receptor that is released from stromal cells and osteoblasts to inhibit the interaction between RANKL and RANK. Although the precise mechanism of bone loss in periodontitis is unknown, the differentiation and activation of osteoclasts by OPG-ODF-RANK signaling might play the role in periodontal bone destruction. The relationship between the concentration of sex hormones and the expression of ODF and OPG was examined by treating human gingival fibroblasts and periodontal ligament cells with the normal serum concentration of estrogen or progesterone during menstruation or at menopause. The ODF/OPG relative ratio was elevated at the concentration observed during ovulation in human gingival fibroblasts and at the concentration observed between ovulation and menstruation in periodontal ligament cells treated with estrogen. However, the ratio was <1 at all concentrations in both cells treated with progesterone. In the case of menopause simulated by estrogen depletion, the ratio was <1 in human gingival fibroblasts but >1 in periodontal ligament cells.

• The Korean Journal of Physiology and Pharmacology
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• v.24 no.4
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• pp.319-328
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• 2020

High fructose intake induces hyperglycemia and hypertension. However, the mechanism by which fructose induces metabolic syndrome is largely unknown. We hypothesized that high fructose intake induces activation of the renin-angiotensin system (RAS), resulting in hypertension and metabolic syndrome. We provided 11-week-old Sprague-Dawley rats with drinking water, with or without 20% fructose, for two weeks. We measured serum renin, angiotensin II (Ang II), and aldosterone (Aldo) using ELISA kits. The expression of RAS genes was determined by quantitative reverse transcription polymerase chain reaction. High fructose intake increased body weight and water retention, regardless of food intake or urine volume. After two weeks, fructose intake induced glucose intolerance and hypertension. High fructose intake increased serum renin, Ang II, triglyceride, and cholesterol levels, but not Aldo levels. High fructose intake increased the expression of angiotensinogen in the liver; angiotensin-converting enzyme in the lungs; and renin, angiotensin II type 1a receptor (AT1aR), and angiotensin II type 1b receptor (AT1bR) in the kidneys. However, expression of AT1aR and AT1bR in the adrenal glands did not increase in rats given fructose. Taken together, these results indicate that high fructose intake induces activation of RAS, resulting in hypertension and metabolic syndrome.

• Journal of Biomedical and Translational Research
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• v.19 no.4
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• pp.86-91
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• 2018

Angiotensin receptor blockers, such as telmisartan, are considered effective in the treatment of hypertension and proteinuria due to chronic kidney disease (CKD) in cats. It selectively blocks the $AT_1$ receptor and does not affect the $AT_2$ receptor, thus effectively blocking the activity of the renin angiotensin aldosterone system. This study aims to compare over time the changes in various indicators, including systemic hypertension and proteinuria, before and after the administration of telmisartan in cats with CKD. Decrease in blood pressure (BP) (p<0.001) and urine protein to creatinine (UP/C) ratio (p<0.001) were found to be statistically significant over time after the administration of telmisartan. BP and the UP/C ratio were $160{\pm} 22.2$ and $0.50{\pm}0.647$ before telmisartan administration (Day 0), $150{\pm}21.0$ and $0.27{\pm}0.487$ on the 30th day (Day 30), $150{\pm}17.0$ and $0.25{\pm}0.376$ on the 60th day (Day 60), and $140{\pm}17.8$ and $0.15{\pm}0.233$ on the 90th day (Day 90) after administration, respectively. BP and UP/C were statistically significantly lower in cats with CKD over time at each time point from Day 0 to Day 90 at 30 day intervals. Especially after 90 days of telmisartan administration, the improvement of BP and UP/C were estimated to be about 20 mmHg and 0.35, respectively. In conclusion, the oral administration of telmisartan to cats with CKD is effective in improving BP and proteinuria, which has a positive effect on long-term survival in cats with CKD.

• Journal of Yeungnam Medical Science
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• v.30 no.1
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• pp.10-16
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• 2013

Background: Toll-like receptors (TLRs) are well-known pattern recognition receptors. Among the 13 TLRs, TLR2 is the most known receptor for immune response. It activates mitogen-activated protein kinases (MAPKs), which are counterbalanced by MAPK phosphatases [MKPs or dual-specificity phosphatases (DUSPs)]. However, the regulatory mechanism of DUSPs is still unclear. In this study, the effect of a TLR2 ligand (TLR2L, Pam3CSK4) on DUSP4 expression in Raw264.7 cells was demonstrated. Methods: A Raw264.7 mouse macrophage cell line was cultured in Dulbecco's modified Eagle's medium supplemented with 10% fetal bovine serum and 1% antibiotics (100 U/mL penicillin and 100 g/mL streptomycin) at $37^{\circ}C$ in 5% $CO_2$. TLR2L (Pam3CSK4)-mediated DUSP4 expressions were confirmed with RT-PCR and western blot analysis. In addition, the detection of reactive oxygen species (ROS) was measured with lucigenin assay. Results: Pam3CSK4 induced the expression of DUSP1, 2, 4, 5 and 16. The DUSP4 expression was also increased by TLR4 and 9 agonists (lipopolysaccharide and CpG ODN, respectively). Pam3CSK4 also induced ERK1/2 phosphorylation and ROS production, and the Pam3CSK4-induced DUSP4 expression was decreased by ERK1/2 (U0126) and ROS (DPI) inhibitors. U0126 suppressed the ROS production by Pam3CSK4. Conclusion: Pam3CSK4-mediated DUSP4 expression is regulated by ERK1/2 and ROS. This finding suggests the physiological importance of DUSP4 in TLR2-mediated immune response.

• BMB Reports
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• v.34 no.2
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• pp.123-129
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• 2001

Cellular response to ionizing radiation is affected by cell types, radiation doses, and post-irradiation time. Based on the trypan blue dye exclusion assay in normal oral mucosal cells (OM cells), a 48 h post-irradiation was sufffcient and an adequate time point for the evaluation of radiation sensitivity Its $LD_{50}$ was approximately 1.83 Gy To investigate possible biomarkers useful for the biological radiodosimetry of normal epithelial cells (p53, c-fos, cyclin D1, cdc-2, pRb) EGF receptor phosphorylation and Erk activation were evaluated at different radiation doses and different post-irradiation times. From 0.5 Gy, p53 was accumulated in the nucleus of basal cells of the OM raft culture at 4 h post-irradiation and sustained up to 24 h post-irradiation, which suggests that radiation-induced apoptosis or damage repair was not yet completed. The number of p53 positive cells and biosynthesis of p53 were correlated with radiation doses. Both cyclin D1 and c-fos were only transiently induced within 1 h post-irradiation. Cyclin D1 was induced at all radiation doses. However, cfos induction was highest at 0.1 Gy, approximately 7.3 fold more induction than the control, whose induction was reduced in a reverse correlation with radiation dose. The phosphorylation pattern of cdc-2 and pRb were unaffected by radiation. In contrast to A431 tails overexpressing the EGF receptor approximately 8.5 fold higher than normal epithelial, the OM cells reduced the basal level of the EGF receptor phosphorylation in a radiation dose dependent fashion. In conclusion, among radiation-induced biomolecules, the p53 nuclear accumulation may be considered for the future development of a useful marker far biological radiodosimetry in normal epithelial tissue since it was sustained for a longer period and showed a dose response relationship. Specific c-fos induction at a low dose may also be an important finding in this study It needs to be studied further for the elucidation of its possible connection with the low dose radio-adaptive response.

• Journal of Applied Biological Chemistry
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• v.44 no.3
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• pp.125-130
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• 2001

A putative protein encoded by Arabidopsis AtMTN3 gene, a homologue of Medicago truncatula MTN3, consists of 285 amino acid residues, and has a predicted molecular mass of 31.5 kDa and a calculated pI of 9.1. Primary amino acid sequence analyses have revealed that the protein contains seven putative transmembrane regions with N-terminus oriented to the outside of the membrane. The AtMTN3 protein shows overall 16.4% of amino acid identity with the rat GALR3 protein, known to be a G-protein-coupled receptor. The gene is present as a single copy in the Arabidopsis genome, and expressed in aerial parts but not in roots of Arabidopsis. Therefore, AtMTN3 appears not to be specifically involved in Rhizobium-induced nodule development, as was predicted for the MTN3 gene. These proteins possibly mediate signal transmission through G-protein-coupled pathways during general interactions between plants and symbiotic or pathogenic microbes.

• Toxicological Research
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• v.8 no.1
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• pp.9-15
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• 1992

Hydroxybrazilin was examined for its effects on glycogen synthesis in primary cultured rat hepatocytes. At 10-6 M hydroxybrazilin, glycogen synthesis was increased in basal state, but not in insulin stimulated state. However, any signiFicant changes were nor observed at 10-5 M hydroxybrazilin in both states. The glycogen synthesis was rather suppressed at 10-5M hydroxybrazilin. It was also observed that hydroxybrazilin increased insulin sensitivity but not insulin responsiveness at 10-5M concentration. These results suggest that hydroxybrazilin might exert hypoglycemic action through its effects on insulin receptor and post receptor events.

• Journal of Microbiology and Biotechnology
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• v.32 no.8
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• pp.1034-1040
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• 2022

Fas-associated death domain (FADD) is an adapter molecule that bridges the interaction between receptor-interacting protein 1 (RIP1) and aspartate-specific cysteine protease-8 (caspase-8). As the primary mediator of apoptotic cell death, caspase-8 has two N-terminal death-effector domains (DEDs) and it interacts with other proteins in the DED subfamily through several conserved residues. In the tumor necrosis receptor-1 (TNFR-1)-dependent signaling pathway, apoptosis is triggered by the caspase-8/FADD complex by stimulating receptor internalization. However, the molecular mechanism of complex formation by the DED proteins remains poorly understood. Here, we found that direct DED-DED interaction between FADD and caspase-8 and the structure-based mutations (Y8D/I128A, E12A/I128A, E12R/I128A, K39A/I128A, K39D/I128A, F122A/I128A, and L123A/I128A) of caspase-8 disrupted formation of the stable DED complex with FADD. Moreover, the monomeric crystal structure of the caspase-8 DEDs (F122A/I128A) was solved at 1.7 Å. This study will provide new insight into the interaction mechanism and structural characteristics between FADD and caspase-8 DED subfamily proteins.