• Journal of Yeungnam Medical Science
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• v.14 no.1
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• pp.53-66
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• 1997

Insulin resistance is a prominent feature of diabetic state and has heterogeneous nature. However, the pathogenetic sequence of events leading to the emergence of the defect in insulin action remains controversial. It is well-known that prolonged hyperglycemia and hyperinsulinemia are one of the causes of development of insulin resistance, but both hyperglycemia and hyperinsulinemia stimulate glucose uptake in peripheral tissue. Therefore, it is hypothesized that insulin resistance may be generated by a kind of protective mechanism preventing cellular hypertrophy. In this study, to evaluate whether the acutely increased glucose uptake inhibits further glucose transport stimulated by insulin, insulin sensitivity was measured after preloaded glucose infusion for 2 hours at various conditions in rats. And also, to evaluate the mechanism of decreased insulin sensitivity, insulin receptor binding affinity and glucose transporter 4 (GLUT4) protein of plasma membrane of gastrocnemius muscle were assayed after hyperinsulinemic euglycemic clamp studies. Experimental animals were divided into five groups according to conditions of preloaded glucose infusion: group I, basal insulin ($14{\pm}1.9{\mu}U/ml$) and basal glucose ($75{\pm}0.7mg/dl$), by normal saline infusion; group II, normal insulin ($33{\pm}3.8{\mu}U/ml$) and hyperglycemia ($207{\pm}6.3mg/dl$), by somatostatin and glucose infusion; group III, hyperinsulinemia ($134{\pm}34.8{\mu}U/ml$) and hyperglycemia ($204{\pm}4.6mg/dl$), by glucose infusion; group IV, supramaximal insulin ($5006{\pm}396.1{\mu}U/ml$) and euglycemia ($l00{\pm}2.2mg/dl$), by insulin and glucose infusion; group V, supramaximal insulin ($4813{\pm}687.9{\mu}U/ml$) and hyperglycemia ($233{\pm}3.1mg/dl$), by insulin and glucose infusion. Insulin sensitivity was assessed with hyperinsulinemic euglycemic clamp technique. The amounts of preloaded glucose infusion(gm/kg) were $1.88{\pm}0.151$ in group II, $2.69{\pm}0.239$ in group III, $3.54{\pm}0.198$ in group IV, and $4.32{\pm}0.621$ in group V. Disappearance rates of glucose (Rd, mg/kg/min) at steady state of hyperinsulinemic euglycemic clamp studies were $16.9{\pm}3.88$ in group I, $13.5{\pm}1.05$ in group II, $11.2{\pm}1.17$ in group III, $13.2{\pm}2.05$ in group IV, and $10.4{\pm}1.01$ in group V. A negative correlation was observed between amount of preloaded glucose and Rd (r=-0.701, p<0.001) when all studies were combined. Insulin receptor binding affinity and content of GLUT4 were not significantly different in all experimental groups. These results suggest that increased glucose uptake may inhibit further glucose transport and lead to decreased insulin sensitivity.

• Tuberculosis and Respiratory Diseases
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• v.45 no.4
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• pp.846-860
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• 1998

Background: Endotoxin (LPS : lipopolysaccharide), a potent activator of immune system, can induce acute and chronic inflammation through the production of cytokines by a variety of cells, such as monocytes, endothelial cells, lymphocytes, eosinophils, neutrophils and fibroblasts. LPS stimulate the mononucelar cells by two different pathway, the CD14 dependent and independent way, of which the former has been well documented, but not the latter. LPS binds to the LPS-binding protein (LBP), in serum, to make the LPS-LBP complex which interacts with CD14 molecules on the mononuclear cell surface in peripheral blood or is transported to the tissues. In case of high concentration of LPS, LPS can stimulate directly the macrophages without LBP. We investigated to detect the generation of proinflammatory cytokines such as interleukin 1 (IL-1), IL-6 and TNF-$\alpha$ and fibrogenic cytokine, TGF-$\beta$, by peripheral blood mononuclear cells (PBMC) after LPS stimulation under serum-free conditions, which lacks LBPs. Methods : PBMC were obtained by centrifugation on Ficoll Hypaque solution of peripheral venous bloods from healthy normal subjects, then stimulated in the presence of LPS (0.1 ${\mu}g/mL$ to 100 ${\mu}g/mL$ ). The activities of IL-1, IL-6, TNF, and TGF-$\beta$ were measured by bioassaies using cytokines - dependent proliferating or inhibiting cell lines. The cellular sources producing the cytokines was investigated by immunohistochemical stains and in situ hybridization. Results : PBMC started to produce IL-6, TNF-$\alpha$ and TGF-$\beta$ in 1 hr, 4 hrs and 8hrs, respectively, after LPS stimulation. The production of IL-6, TNF-$\alpha$ and TGF-$\beta$ continuously increased 96 hrs after stimulation of LPS. The amount of production was 19.8 ng/ml of IL-6 by $10^5$ PBMC, 4.1 ng/mL of TNF by $10^6$ PBMC and 34.4 pg/mL of TGF-$\beta$ by $2{\times}10^6$ PBMC. The immunoreactivity to IL-6, TNF-$\alpha$ and TGF-$\beta$ were detected on monocytes in LPS-stimulated PBMC. Some of lymphocytes showed positive immunoreactivity to TGF-$\beta$. Double immunohistochemical stain showed that IL-1$\beta$, IL-6, TNF-$\alpha$ expression was not associated with CD14 postivity on monocytes. IL-1$\beta$, IL-6, TNF-$\alpha$ and TGF-$\beta$mRNA expression were same as observed in immunoreactivity for each cytokines. Conclusion: When monocytes are stimulated with LPS under serum-free conditions, IL-6 and TNF-$\alpha$ are secreted in early stage of inflammation. In contrast, the secretion of TGF-$\beta$ arise in the late stages and that is maintained after 96 hrs. The main cells releasing IL-1$\beta$, IL-6, TNF-$\alpha$ and TGF-$\beta$ are monocytes, but also lymphocytes can secret TGF-$\beta$.

• Radiation Oncology Journal
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• v.19 no.2
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• pp.171-180
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• 2001

Purpose : Expression of TIMP, intrinsic inhibitor of MMP, is regulated by signal transduction in response to genotoxins and is likely to be an important step in metastasis, angiogenesis and wound healing after ionizing radiation. Therefore, we studied radiation mediated TIMP expression and its mechanism in head and neck cancer cell lines. Materials and Methods : Human head and neck cancer cell lines established at Asan Medical Center were used and radiosensitivity $(D_0)$, radiation cytotoxicity and metastatic potential were measured by clonogenic assay, n assay and invasion assay, respectively. The conditioned medium was prepared at 24 hours and 48 hours after 2 Gy and 10 Gy irradiation and expression of TIMP protein was measured by Elisa assay with specific antibodies against human TIMP. hTIMP1 promoter region was cloned and TIMP1 luciferase reporter vector was constructed. The reporter vector was transfected to AMC-HN-1 and -HN-9 cells with or without expression vector Ras, then the cells were exposed to radiation or PMA, PKC activator. EMSA was peformed with oligonucleotide (-59/-53 element and SP1) of TIMP1 promoter. Results : $D_0$ of HN-1, -2, -3, -5 and -9 cell lines were 1.55 Gy, 1.8 Gy, 1.5 Gt, 1.55 Gy and 2.45 Gy respectively. n assay confirmed cell viability, over $94\%$ at 24hrs, 48hrs after 2 Gy irradiation and over 73% after 10 Gy irradiation. Elisa assay confirmed that cells secreted TIMP1, 2 proteins continuously. After 2 Gy irradiation, TIMP2 secretion was decreased at 24hrs in HN-1 and HN-9 cell lines but after 10 Gy irradiation, it was increased in all cell lines. At 48hrs after irradiation, it was increased in HN-1 but decreased in HN-9 cells. But the change in TIMP secretion by RT was mild. The transcription of TIMP1 gene in HN-1 was induced by PMA but in HN-9 cell lines, it was suppressed. Wild type Ras induced the TIMP-1 transcription by 20 fold and 4 fold in HN-1 and HN-9 respectively. The binding activity to -59/-53, AP1 motif was increased by RT, but not to SP1 motif in both cell lines. Conclusions : We observed the difference of expression and activity of TIMPs between radiosensitive and radioresistant cell line and the different signal transduction pathway between in these cell lines may contribute the different radiosensitivity. Further research to investigate the radiation response and its signal pathway of TIMPs is needed.

• Molecules and Cells
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• v.27 no.5
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• pp.591-599
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• 2009

Nicotinic acetylcholine receptors (nAChRs) play important roles in nervous system functions and are involved in a variety of diseases. We previously demonstrated that ginsenosides, the active ingredients of Panax ginseng, inhibit subsets of nAChR channel currents, but not ${\alpha}7$, expressed in Xenopus laevis oocytes. Mutation of the highly conserved Leu247 to Thr247 in the transmembrane domain 2 (TM2) channel pore region of ${\alpha}7$ nAChR induces alterations in channel gating properties and converts ${\alpha}7$ nAChR antagonists into agonists. In the present study, we assessed how point mutations in the Leu247 residue leading to various amino acids affect 20(S)-ginsenoside $Rg_3$ ($Rg_3$) activity against the ${\alpha}7$ nAChR. Mutation of L247 to L247A, L247D, L247E, L247I, L247S, and L247T, but not L247K, rendered mutant receptors sensitive to $Rg_3$. We further characterized $Rg_3$ regulation of L247T receptors. We found that $Rg_3$ inhibition of mutant ${\alpha}7$ nAChR channel currents was reversible and concentration-dependent. $Rg_3$ inhibition was strongly voltage-dependent and noncompetitive manner. These results indicate that the interaction between $Rg_3$ and mutant receptors might differ from its interaction with the wild-type receptor. To identify differences in $Rg_3$ interactions between wild-type and L247T receptors, we utilized docked modeling. This modeling revealed that $Rg_3$ forms hydrogen bonds with amino acids, such as Ser240 of subunit I and Thr244 of subunit II and V at the channel pore, whereas $Rg_3$ localizes at the interface of the two wild-type receptor subunits. These results indicate that mutation of Leu247 to Thr247 induces conformational changes in the wild-type receptor and provides a binding pocket for $Rg_3$ at the channel pore.

• Journal of Life Science
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• v.23 no.9
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• pp.1096-1103
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• 2013

Chronic traumatic encephalopathy (CTE), which is common in athletes, is a progressive neurodegenerative disease and a long-term consequence of repetitive closed head injuries. CTE is regarded as a chronic brain syndrome due to the effects of repetitive traumatic brain injury (TBI). Because neurotrophic factors are neuroprotective in models of brain and spinal cord injuries, we examined the effects of cerebrolysin, a mixture of various neurotrophic factors, on brain pathology in a mouse model of repetitive mild TBI (rmTBI), which is a good model of CTE. Five groups were created and treated as follows: groups 1 and 2: rmTBI for 4 weeks following cerebrolysin injection for 4 weeks; groups 3 and 4: rmTBI for 8 weeks with or without cerebrolysin injection for 4 weeks; group 5: control. We found that p-tau expression was increased in the pyramidal layer of the cortex and hippocampus, particularly the CA3 region, but not in the CA1 region and the dentate gyrus (DG). Intra-tail vein administration of cerebrolysin ($10{\mu}l$ of 1 mg/ml) after/during rmTBI treatment reduced p-tau expression in both the cortex and hippocampus. Histological analysis revealed mild astrocyte activation (increased expression of glial fibrillary acidic protein (GFAP)) but not microglia activation (ionized calcium binding adaptor molecule 1 (iba-1) expression) and peripheral macrophage infiltration (CD45). Additionally, administration of cerebrolysin after rmTBI resulted in reduced astrocyte activation. These observations in rmTBI demonstrated that cerebrolysin treatment reduces phosphorylation of tau and astrocyte activation, attenuates brain pathology, and mitigates function deficits in TBI. Taken together, our observations suggest that cerebrolysin has potential therapeutic value in CTE.

• Journal of Life Science
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• v.25 no.10
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• pp.1081-1090
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• 2015

Diabetes has been one of major health risks in industrialized countries. Allium hookeri is a wild herb distributed in India and Myanmar. The root of the plant has been used as food and medicine in Southeast Asia. We investigated Allium hookeri extract improves type 2 diabetes mellitus in C57BL/KSJ db/db obese mouse. C57BL/KSJ db/db obese mouse arise out of Type 2 diabetes and we treated Allium hookeri methanol extract 400 mg/kg (AH 400), 800 mg/kg (AH 800), positive control group (thiazolidinedine;TZDs) were administered orally for 8weeks. AH treated group normalized lipid enzyme system (triglyceride, total cholesterol, HDL-cholesterol and LDL-cholesterol) and serum glucose, HbA1c and plasma insulin level. AH treated group recovered β-cell damage by hyperglycemia and fatty liver disease. AH treated group significantly up regulated expression of Peroxisome proliferator-activated receptor gamma (PPAR-γ), pyruvate dehydrogenase kinase4 (PDK4), Sterol regulatory element-binding protein 1c (SREBP 1) and fork head box O1 (FOX 01) proteins in C57BL/KSJ db/db obese mouse liver. And we found that AH treated group decreased hepatic malondialdehyde formation in C57BL/KSJ db/db obese mouse liver. These results indicate that Allium hookeri methanol extract might be a potential anti-diabetic agent and could be useful in the treatment of type 2 diabetes mellitus.

• Journal of Life Science
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• v.24 no.2
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• pp.137-147
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• 2014

Cortex ulmi pumilae, the cortex of Ulmus davidiana var. japonica, has been used in traditional folk medicine for its anti-inflammatory effect. Although its various bioactivities such as anti-inflammatory, anti-microbial, and anti-cancer, have been reported, the anti-adipogenic activity of cortex ulmi pumilae remains unclarified. In the present study, we investigated the effect of cortex ulmi pumilae extract on adipocyte differentiation in 3T3-L1 preadipocytes. Treatment with cortex ulmi pumilae extract significantly reduced the formation of lipid droplets and triglyceride content in a dose-dependent manner; this is associated with an inhibition of the adipogenic transcription factors, CCAAT/enhancer binding protein ${\alpha}$ ($C/EBP{\alpha}$), $C/EBP{\beta}$, and peroxisome proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$). In addition, cortex ulmi pumilae extract treatment during the early stage of adipogenesis showed more efficient anti-adipogenic activity than treatment during other stages of adipogenesis. Cortex ulmi pumilae extract also inhibited cell proliferation and induced G1 arrest of 3T3-L1 cells in the early stage of adipogenesis. This was associated with upregulated expression of Cdk inhibitor p21 and downregulated expression of cyclin E and phospho-Rb, indicating that cortex ulmi pumilae extract blocks mitotic clonal expansion by cell cycle regulation. Taken together, these results suggest that cortex ulmi pumilae extract possesses anti-adipogenic activity through the inhibition of adipocyte differentiation by blocking mitotic clonal expansion.

• Journal of Nutrition and Health
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• v.4 no.1
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• pp.1-19
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• 1971

Nutritional anemia is an important nutritional problem affecting large population groups in most developing countries. Nutritional anemia is caused by the absence of any dietary essential involed in hemoglobin formation or by poor absorption of these dietary components. The most likely causes are lack of dietary iron, and folate, vitamin $B_{12}$ and high qualify protein. Anemia is considered to be a late mainfeastation of nutritional deficiencies, and even mild anemia is not the earilest sign of such a deficiency. Therefore, the object of therapy is to correct underlying deficiency rather than merely its manifestation. Iron deficiency anemia is generally much the most common form of anemia. And it is very prevalent particularly in pregnant women and young children, especially under five year of life. According to the rapid growth rate of infants, dietary iron should he provided for infants over three months of age in adequate amounts for the synthesis of hemoglobin required by the increasing blood volume and for the demands of newly formed cells. The principal causes of iron deficiency anemia are an inadequate dietary iron content, interference with absorption of iron from the intestine, excessive losses of iron from the body, disturbance of iron metabolism by infection, and social and cultural environments. The present study is planned to obtain informations concerning nutritional anemia through anthropometric and biochemical determinations for the assessment of nutriture in pre-school children. Determination was taken in 226 pre-school children in ruraI arae in 1968, 122 pre-school children in 1970, and 1526 hospitalized pre-school children in 1970. The results of this study are as follows; (1) According to Iowa Malnutrition Borderline (85 percentile) for weight, the proportions of underweighed pre-school boys and girls in rural area were 47.2% and 46.2% in1968, and were 36.1% and 51.8% in 1970. According to Iowa Malnutrition Borderline for height, the proportions of underheight boys and girls in rural area were 30.5% and 33.7%, and were 26.2% and 21.8% in 1970. Malnutrition scores of underweight for height values of boys and girls in rural area were 19.3 and 17.3 in 1968, and the scores of boys and girls were 15.6 and 15.5 in 1970. (2) The mean hemoglobin values of boys and girls in rural area were $11.2{\pm}1.8g/100ml\;and\;11.4{\pm}1.6g/100ml$ in 1968. In 1970, the mean values of boys and girls in rural area were $11.3{\pm}1.3g/100ml\;and\;11.7{\pm}2.4g/100ml$. The mean hemoglobin values of hospitalized boys and girls were $11.9{\pm}2.2g/100ml\;and\;11.7{\pm}2.4g/100ml$ in 1970. It is found that 92 of 215 children (42.7%) in rural area had concentrations of hemoglobin less than 11.0g/100ml in 1968. In 1970, 55 of 121 children (45.4%) in rural area and 559 of 1526 hospitalized children (36.6%) had concentrations of hemoglobin less than 11.0g/100ml. (3) The mean hematocrit levels of hospitalized boys and girls were $35{\pm}26.8%\;and\;35.4{\pm}6.4%$ in 1970. And 443 of 1334 hospitalized children (33.2%) had hematocrit values below 33%. (4) The average mean corpuscular hemoglobin concentration levels of hospitalized boys and girls were $32.4{\pm}2.2\;and\;32.3{\pm}2.2$ in 1970. And 1016 of 1352 hospitalized children (75.1%) had the mean corpuscular hemoglobin values below 34. (5) The mean iron values of young children in rural area and hospitalized children were $62.0{\pm}6.3{\mu}g/100ml\;and\;60.7{\pm}22.8{\mu}g/100ml$. The proportions of anemia cases below $50{\mu}g/100ml$ in rural area was 37.9%, and 34.3% in hospitalized children. (6) The mean total iron binding capacity of young children in rural area was $376{\pm}57.88{\mu}g/100ml,\;and\;342.2{\pm}6.15{\mu}g/100ml$ in hospitalized children. (7) The average transferrin saturation percentage of young children in rural area was $16.9{\pm}4.7%,\;and\;18.0{\pm}8.4%$ in hospitalized children. The proportions of anemia cases below 15% of young chi1dren in rural area and hospitalized children were 48.3% and 41.2%. Therefore, authors wish to recommend that the following further studies should be undertaken: (1) Standardization of simplied laboratory examination of nutritional anemia. (2) The prevalence of nutritional anemia and the requirements of iron, folate, and vitamin $B_{12}$ of pre-school children. (3) The content and absorption of iron in Korean food. (4) The pathogenesis of nutritional anemia and prevention of parasitic disease. (5) Maternal health and nutrition education.

• Journal of Nutrition and Health
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• v.51 no.4
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• pp.275-286
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• 2018

Purpose: Our previous study demonstrated that persimmon (Diospyros kaki Thumb.) at different stages of ripening provided different protective effects against high-fat/cholesterol diet (HFD)-induced dyslipidemia in rats. In this study, we compared the metabolites profile and gene expressions related to triglyceride (TG)/cholesterol metabolism in vitro and in vivo after treating with persimmon water extracts (PWE) or tannin-enriched persimmon concentrate (TEP). Methods: Primary and secondary metabolites in test materials were determined by GC-TOF/MS, UHPLC-LTQ-ESI-IT-MS/MS, and UPLC-Q-TOF-MS. The expression of genes related to TG and cholesterol metabolism were determined by RT-PCR both in HepG2 cells stimulated by oleic acid/palmitic acid and in liver tissues obtained from Wistar rats fed with HFD and PWE at 0, 150, 300, and 600 mg/d (experiment I) or TEP at 0, 7, 14, and 28 mg/d (experiment II) by oral gavage for 9 weeks. Results: PLS-DA analysis and heatmap analysis demonstrated significantly differential profiling of metabolites of PWE and TEP according to processing of persimmon powder. In vitro, TEP showed similar hypolipidemic effects as PWE, but significantly enhanced hypocholesterolemic effects compared to PWE in sterol regulatory element-binding protein 2 (SREBP2), HMG-CoA reductase (HMGCR), proprotein convertase subtilisin/kexin type 9 (PCSK9), cholesterol $7{\alpha}-hydroxylase$ (CYP7A1), and low density lipoprotein receptor (LDLR) gene expression. Consistently, TEP and PWE showed similar hypolipidemic capacity in vivo, but significantly enhanced hypocholesterolemic capacity in terms of SREBP2, HMGCR, and bile salt export pump (BSEP) gene expression. Conclusion: These results suggest that column extraction after hot water extraction may be a good strategy to enhance tannins and long-chain fatty acid amides, which might cause stimulation of hypocholesterolemic actions through downregulation of cholesterol biosynthesis gene expression and upregulation of LDL receptor gene expression.

• Korean Journal of Food Science and Technology
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• v.46 no.1
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• pp.73-78
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• 2014

This study investigated the nutritional components and physicochemical characteristics of Jerusalem artichoke. The moisture, crude protein, crude fat, crude ash and carbohydrate content of the Jerusalem artichoke were $5.06{\pm}0.08$, $8.30{\pm}0.26$, $0.70{\pm}0.16$, $5.04{\pm}0.03$, and 80.90%, respectively. The total sugar content of Jerusalem artichoke was $50.48{\pm}1.11$ mg/g, and the Hunter color space coordinates were $L=94.16{\pm}0.03$, $a=0.32{\pm}0.01$ and $b=0.30{\pm}0.01$. The water binding capacity and water activity of the Jerusalem artichoke were $4.06{\pm}0.16$ g/g and $0.245{\pm}0.005$, respectively. The total amino-acid content of the Jerusalem artichoke was $1.337{\times}10^4$ mg/kg, and essential amino acid was 2,737 mg/kg. The total free sugar of the Jerusalem artichoke was 4.12%. Linoleic acid (0.21%) was found to be a common fatty acid in the Jerusalem artichoke. Among the minerals, potassium (2,489 mg%) was found to be the most abundant in the Jerusalem artichoke. The total phenol and flavonoid contents were $3.06{\pm}0.07$ mg GAE/g and $1.89{\pm}0.03$ mg QE/g, respectively. The vitamin C content of the Jerusalem artichoke was $3.43{\pm}0.07$ mg%.