• Korean Journal of Veterinary Research
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• v.44 no.4
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• pp.497-505
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• 2004

The proliferation of mesangial cells has been associated with the development of diabetic nephropathy. The cell proliferation has been regulated by diverse growth factors. Among them, insulin like growth factors(IGFs) are also involved in the pathogenesis of diabetic nephropathy. However, it is not yet known about the effect of high glucose on IGF-I and IGF-II secretion and the relationship between high glucose-induced secretion of IGFs and PKC or oxidative stress in the mesangial cells. Thus, we examined the mechanisms by which high glucose regulates secretion of IGFs in mesangial cells. High glucose(25 mM) increased IGF-I and IGF-II secretion. High glucose-induced increase of IGF-I and IGF-II secretion were blocked by taurine($2{\times}10^{-3}$ M), N-acetyl cystein(NAC, $10^{-5}M$), or GSH($10^{-5}M$) (antioxidants), suggesting the role of oxidative stress. High glucose-induced secretion of IGF-I and IGF-II were blocked by H-7, staurosporine, and bisindolylmaleimide I(protein kinase C inhibitors). On the other hand, high glucose also increased lipid peroxide (LPO) formation in a dose dependent manner. In addition, high glucoseinduced stimulation of LPO formation was blocked by PKC inhibitors. These results suggest that PKC is responsible for the increase of oxidative stress in the action of high glucose-induced secretion of IGF-I and IGF-II in mesangial cells. In conclusion, high glucose stimulates IGF-I and IGF-II secretion via PKCoxidative stress signal pathways in mesangial cells.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.11a
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• pp.99-99
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• 2002

The hormone resistin is associated with typeII diabetes mellitus in rodent model. Resistin impairs glucose tolerance and insulin action. A new class of anti-diabetic drugs were called thiazolidinediones (TZDs) downregulates a resistin which is induced during adipocyte differentiation. But the connection between increased adiposity and resistin remains unknown. The objectives of this study was to clone a mouse resistin cDNA and to generate transgenic mice overexpressing mouse resistin gene. The 555 bp of mouse resistin was amplified from mob cDNAS by polymerase chain reaction (PCR) and cloned into pCR$\^$(R)/ 2.1 TOPO T-vector. Mouse resistin mRNA on the basis of Genbank sequence (acession no. AF323080). Then, the PCR product was cloned into pTargeT$\^$TM/ mammalian expression vector that has pCMV promoter and chimeric intron. Restriction enzyme analysis with BamH I and Not I was carried out to determine an orientation of the insert in the vector. The pCMV-mus/resistin gene was prepared from previous recombinant pTargeT$\^$TM/-mus/resistin by digestion of Bgl II, and has used for microinjection into pronuclei of one cell embryos. The microinjected embryos were transfered to pseudopregnant foster-mother. Mouse resistin expression was detected in transgenic F1 mice by Reverse Transcriptase- Polymerase Chain Reaction (RT-PCR). Resistin gene expression mouse has heavier body weight which was measured higher level of plasma glucose than that of normal mouse. And in diet-induced experiments, the abdominal fat pads were isolated from each 24h starvation and re-feeding after fasting group mice that were assessed by RT-PCR analysis. In fasting group mice, resistin expression was higher than that of re-feeding group mice. This result suggests that the resistin gene overexpressing mice may be became to obesity and be useful as an animal disease model to be diabetes mellitus caused by insulin resistance of resistin.

• Journal of Korean Medicine for Obesity Research
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• v.23 no.2
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• pp.51-59
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• 2023

Objectives: Despite the pharmacological potential of the roots and stems of hemp based on literatures, active research has not been conducted for a long time. Comparative experiments were conducted on antioxidant and anti-inflammatory effects and improvement of glucose uptake using Cannabis root and stem extracts. Methods: Antioxidant contents in Cannabis root and stem extracts were examined with total phenolic, tannin, flavonoid assay. Anti-inflammatory properties were tested in lipopolysaccharides-treated RAW264.7 cells. Efficacy of Cannabis root and stem extracts on glucose uptake was investigated using fluorescent glucose analog (2-NBDG) in palmitate-treated HepG2 cells. The mechanism of action on metabolism was examined by western blot. Results: Antioxidant and anti-inflammatory efficacy were greater in stem extracts, but improvements in glucose uptake performed under various conditions were found to be greater in root extracts. It is assumed that Cannabis root extracts exhibited an improvement in glucose uptake through mechanisms such as AMP-activated protein kinase activation, not depending on general antioxidant and anti-inflammatory effects. Conclusions: Further research is needed on the mechanisms and substances that exhibit the anti-diabetic effects of Cannabis roots and stems.

• Journal of Acupuncture Research
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• v.27 no.6
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• pp.31-42
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• 2010

Objectives : The aim of this study was to investigate the anti-obesity potential and mechanisms of action of Rhizoma Atractylodis(RA) herbal acupuncture in high fat diet- induced obese ICR mice. Methods : Sample solutions for herbal acupuncture were prepared from the Rhizoma Atractylodis water extract powder at concentration of 150mg/kg and 300mg/kg with distilled water. Five week-old ICR mice acclimatized to the laboratory environment for 1 week were allocated into four groups: regular diet group (RD), high fat diet group(HFD), groups fed HFD with 150mg/kg RA herbal acupuncture treatment (RAE 150) and with 300mg/kg RA herbal acupuncture treatment(RAE 300). Herbal acupuncture groups were injected with either 150mg/kg or 300mg/kg of Rhizoma Atractylodis(RA) subcutaneously onto both Sinsu($BL_{23}$) alternately on the same time everyday for 30days. Body weight, gross appearance of epididymal fat area, blood glucose, insulin, insulin resistance(HOMA-IR), non-esterified fatty acid, cholesterol, triglyceride, AST, ALT, histological analysis of white adipose tissue, gene expression responsible for adipocyte differentiation and AMPK activation were analyzed. Results : RA herbal acupuncture inhibited the development of weight gain, hyperglycemia, hyperinsulinemia, hyperlipidemia, increases of AST and ALT, and the enlargement of fat cell size induced by HFD. Also, RA herbal acupuncture inhibited the expression of PPAR-${\gamma}$, C/$EBP{\alpha}$, aP2, LPL, FAS, SCD-1 and enhanced the activation of AMP-activated protein kinase. Conclusions : The results of this study demonstrate that RA herbal acupuncture can exert the anti-obesity effect and it is partially mediated by activation of AMPK and inhibition of the gene expressions responsible for adipocyte differentiation. Further studies will be required to ascertain the nti-obesity effect and mechanisms of action of RA herbal acupuncture in animal models and human for aclinical application.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2002.07a
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• pp.113-113
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• 2002

Phylogenetically conserved Bcl-2 family proteins play a pivotal role in the regulation of apoptosis from virus to human. Members of the Bcl-2 family consist of antiapoptotic proteins such as Bcl-2, Bcl-xL, and Bcl-w, and proapoptotic proteins such as BAD, Bax, BOD, and Bok. It has been proposed that anti- and proapoptotic Bcl-2 proteins regulate cell death by binding to each other and forming heterodimers. A delicate balance between anti- and proapoptotic Bcl-2 family members exists in each cell and the relative concentration of these two groups of proteins determines whether the cell survives or undergoes apoptosis. Mcl-1 (Myeloid cell :leukemia-1) is a member of the Bcl-2 family proteins and was originally cloned as a differentiation-induced early gene that was activated in the human myeloblastic leukemia cell line, ML-1 . Mcl-1 is expressed in a wide variety of tissues and cells including neoplastic ones. We recently identified a short splicing variant of Mcl-1 short (Mcl-IS) and designated the known Mcl-1 as Mcl-1 long (Mcl-lL). Mcl-lL protein exhibits antiapoptotic activity and possesses the BH (Bcl-2 homology) 1, BH2, BH3, and transmembrane (TM) domains found in related Bcl-2 proteins. In contrast, Mcl-1 S is a BH3 domain-only proapoptotic protein that heterodimerizes with Mcl-lL. Although both Mc1-lL and Mcl-lS proteins contain BH domains fecund in other Bcl-2 family proteins, they are distinguished by their unusually long N-terminal sequences containing PEST (proline, glutamic acid, serine, and threonine) motifs, four pairs of arginine residues, and alanine- and glycine-rich regions. In addition, the expression pattern of Mcl-1 protein is different from that of Bcl-2 suggesting a unique role (or Mcl-1 in apoptosis regulation. Tankyrasel (TRF1-interacting, ankyrin-related ADP-related polymerasel) was originally isolated based on its binding to TRF 1 (telomeric repeat binding factor-1) and contains the sterile alpha motif (SAM) module, 24 ankyrin (ANK) repeats, and the catalytic domain of poly(adenosine diphosphate-ribose) polymerase (PARP). Previous studies showed that tankyrasel promotes telomere elongation in human cells presumably by inhibiting TRFI though its poly(ADP-ribosyl)action by tankyrasel . In addition, tankyrasel poly(ADP-ribosyl)ates Insulin-responsive amino peptidase (IRAP), a resident protein of GLUT4 vesicles, and insulin stimulates the PARP activity of tankyrase1 through its phosphorylation by mitogen-activated protein kinase (MAPK). ADP-ribosylation is a posttranslational modification that usually results in a loss of protein activity presumably by enhancing protein turnover. However, little information is available regarding the physiological function(s) of tankyrase1 other than as a PARP enzyme. In the present study, we found tankyrasel as a specific-binding protein of Mcl-1 Overexpression of tankyrasel led to the inhibition of both the apoptotic activity of Mel-lS and the survival action of Mcl-lL in mammalian cells. Unlike other known tankyrasel-interacting proteins, tankyrasel did not poly(ADP-ribosyl)ate either of the Mcl-1 proteins despite its ability to decrease Mcl-1 proteins expression following coexpression. Therefore, this study provides a novel mechanism to regulate Mcl-1-modulated apoptosis in which tankyrasel downregulates the expression of Mcl-1 proteins without the involvement of its ADP-ribosylation activity.

• Journal of Nutrition and Health
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• v.35 no.2
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• pp.192-200
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• 2002

Conjugated linoleic acid (CLA) is a collective term for positional and geometric isomers of octadecadienoic acid in which the double bonds are conjugated. CLA has anticancer activity in a variety of animal cancer models, and cis-9, trans-11 (c9t11) and trans-10, cis-12(t10c12) CLA are the most predominant isomers present in the synthetic preparations utilized in these animal studies. To compare the ability of c9t11, t10c12 and an isomeric mixture of CLA to inhibit TSU-Prl cell growth, cells were incubated in a serum-free medium with various concentrations of these fatty acids. The isomeric mixture inhibited cell growth in a dose-dependent manner (1-3 $\mu$M) with a 41 $\pm$ 1% inhibition observed at 3 $\mu$M concentration after 48 hours. T10c12 also inhibited cell proliferation in a dote-dependent manner, However, the efficacy and potency of this isomer was much greater than that of the isomeric mixture with a 49 $\pm$ 2% inhibition observed at 0.3 $\mu$M concentration after 48 hours. By contrast, c9t11 slightly increased cell proliferation. To determine whether the growth-inhibiting effect of CLA is related to the changes in production of insulin-like growth factors (IGF) and IGF-binding proteins (IGFBP) by these cells, serum-free conditioned media were collected. Immunoblot analysis of conditioned media using a monoclonal anti-IGF-II antibody showed that both the isomeric mixture and t10c12 inhibited secretion of both mature 7,500 Mr and higher Mr forms of pro IGF-II, whereas c9t11 had no effect. Ligand blot analysis with 125I-IGF-II revealed the presence of two types of IGFBPs : 24,000 Mr IGFBP-4 and 30,000 Mr IGFBP-6. The production of IGFBP-4 slightly decreased at the highest concentrations of the isomeric mixture and t10c12. These results indicate that CLA inhibits human prostate cancer cell growth, an effect largely due to the action of t10c12. The growth inhibition may result, at least in part, from decreased production of IGF-II and IGFBP-4 by these cells.

• Childhood Kidney Diseases
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• v.3 no.2
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• pp.109-116
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• 1999

Purpose: Insulin-like growth factor(IGF)-I and -II are peptide growth factor whose activity is modulated by interaction with the family of six IGF-binding proteins(IGFBPs). IGF-I is detected in rat kidney and has metabolic and growth effects. This study was designed to examine temporal expression of IGFBPs in kidney during renal development and postischemic regeneration in rat. Method: The expression of IGFBPs in kidney during renal development from 15th day of gestation to adult life by using Northern blot analysis. We also examined the renal IGF-IGFBP axis in uremic rat by using Northern blot and immunohistochemistry. Results: The mRNA of IGFBP-1 and -3 were not or barely detected in fetal stages. However, the mRNA level of IGFBP-1 and -3 were increased gradually from day 7 after birth to adult. In contrast, the mRNA of IGFBP-2 and -5 were highly expressed in fetal stages and maintained almost same levels until day 7 (IGFBP-2) or day 30 (IGFBP-5) after birth, then their levels decreased markedly. The mRNA of IGFBP-4 were expressed moderately in fetal kidney and increased gradually after birth. Interestingly, the mRNA of IGFBP-1 and-4 were induced up to 3-5 fold during maximum regeneration period and were recovered to normal levels after acute ischemic injury. In contrast, the mRNA level of IGFBP-3 and-IGFBPrP-1 were decreased slightly at 1 day after ischemic injury, then recovered to normal level during maximum regeneration period. Conclusion: There were differential expressions of IGFBPs in kidney that can modulate IGF action on developing, differentiating, maintaining, and regenerating renal structure and function.

• The Korean Journal of Physiology and Pharmacology
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• v.20 no.2
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• pp.153-160
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• 2016

The objective was to investigate the hypoglycemic action of catalpol in spontaneous diabetes db/db mice. 40 db/db mice were randomly divided into five groups: model control gourp; db/db plus catalpol 40, 80, 120 mg/kg body wt. groups and db/db plus metformin 250 mg/kg group. Age-matched db/m mice were selected as normal control group. The mice were administered with corresponding drugs or solvent by gavage for 4 weeks. The oral glucose tolerance test was carried out at the end of $3^{rd}$ week. After 4 weeks of treatment, the concentrations of fasting blood glucose (FBG), glycated serum protein (GSP), insulin (INS), triglyceride (TG), total cholesterol (TC) and adiponection (APN) in serum were detected. The protein expressions of phosphorylation-$AMPK{\alpha}$1/2 in liver, phosphorylation-$AMPK{\alpha}$1/2 and glucose transporter-4 (GLUT-4) in skeletal muscle and adipose tissues were detected by western blot. Real time RT-PCR was used to detect the mRNA expressions of acetyl-CoA carboxylase (ACC) and Hydroxymethyl glutaric acid acyl CoA reductase (HMGCR) in liver. Our results showed that catalpol could significantly improve the insulin resistance, decrease the serum concentrations of INS, GSP, TG, and TC. The concentrations of APN in serum, the protein expression of phosphorylation-$AMPK{\alpha}$1/2 in liver, phosphorylation-$AMPK{\alpha}$1/2 and GLUT-4 in peripheral tissue were increased. Catalpol could also down regulate the mRNA expressions of ACC and HMGCR in liver. In conclusion, catalpol ameliorates diabetes in db/db mice. It has benefit effects against lipid/glucose metabolism disorder and insulin resistance. The mechanism may be related to up-regulating the expression of phosphorylation-$AMPK{\alpha}$1/2.

• Food Science and Preservation
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• v.24 no.7
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• pp.1007-1016
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• 2017

Melania snail (Semisulcospira libertina) was traditionally used as the healthy food in Korea. It was generally known to improve liver function and heal a diabetes. The aim of this study was to elucidate the anti-diabetic mechanism of melanian snail hydrolysates treated with protamex (MPH) by investigating the inhibitory action on protein tyrosine phosphatase 1B (PTP1B), the improving effect on the insulin resistance in C2C12 myoblast and the protective effect for pancreatic beta-cell (INS-1) under the glucose toxicity. The melania snail hydrolysates treated with protamex (MPH), which showed the highest degree of hydrolysis (43%), and inhibited effectively PTP1B activity ($IC_{50}=15.42{\pm}1.1{\mu}g/mL$), of which inhibitory effect was higher than usolic acid, positive control ($IC_{50}=16.65{\mu}g/mL$). MPH increased the glucose uptake in C2C12 myoblast treated with palmitic acid. In addition, MPH increased insulin mRNA expression level by over 160% with enhanced cell viability in INS-1 cell under the high glucose concentration (30 mM). These results suggest that MHP may improve the diabetic symptom by the inhibiting the PTP1B activity, increasing the glucose uptake in muscle cell and protecting the pancreatic beta-cell from glucose toxicity.

• Tuberculosis and Respiratory Diseases
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• v.50 no.5
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• pp.549-556
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• 2001

Background : IGF-I is an important mitogen in many types of malignancies. Tumors also express many IGF binding proteins, which modulate IGF action. The propose of this study was to evaluate the effect of IGF-I and IGFBP on cell proliferation in mouse lung cancer cells (3LL). Methods : The cellular proliferation of 3LL with the treatment of growth factors was evaluated using MTT assay. Western ligand blot was performed in order to determine whether 3LL cells secrete IGFBPs and we evaluated the effect of IGFBP on cellular proliferation. Results : The treatment of 3LL cells with IGF-I increased cellular proliferation in a serum free media. Western ligand blot of conditioned medium of 3LL with $^{125}I$-IGF-I demonstrated one single major band with an estimated molecular mass of 24 kDa. This band was identified as IGFBP-4 with immunoblot analysis using antisera. The addition of anti-IGFBP-4 antibody to abrogate the effect of IGFBP-4 resulted in increased cellular proliferation suggesting that IGFBP-4 inhibits cell growth. Conclusion : IGF-I increases cellular proliferation, however the secreted IGFBP-4 has an inhibitory function on cell growth in 3LL. These findings suggest that IGF-I and IGFBP are involved in the cell proliferation.