70 results on '"Gwanpyo Koh"'
Search Results
2. Letter: Triglyceride-Glucose Index Predicts Cardiovascular Outcome in Metabolically Unhealthy Obese Population: A Nationwide Population-Based Cohort Study (J Obes Metab Syndr 2022;31:178-86)
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Gwanpyo Koh
- Subjects
Endocrinology, Diabetes and Metabolism - Published
- 2023
3. Efficacy and safety of monotherapy with enavogliflozin in Korean patients with type 2 diabetes mellitus: Results of a 12‐week, multicentre, randomized, double‐blind, placebo‐controlled, phase 2 trial
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Ye Seul Yang, Kyung Wan Min, Seok‐O Park, Kyung‐Soo Kim, Jae Myung Yu, Eun‐Gyoung Hong, Sung Rae Cho, Kyu Chang Won, Yong Hyun Kim, Seungjoon Oh, Sung Hee Choi, Gwanpyo Koh, Wan Huh, Su Young Kim, and Kyong Soo Park
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Endocrinology ,Endocrinology, Diabetes and Metabolism ,Internal Medicine - Published
- 2023
4. Author response for 'Efficacy and Safety of Monotherapy with Enavogliflozin in Korean Patients with Type 2 Diabetes Mellitus: Results of a 12‐week, multi‐center, randomized, double‐blind, placebo‐controlled, phase 2 trial'
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null Ye Seul Yang, null Kyung Wan Min, null Seok‐O Park, null Kyung‐Soo Kim, null Jae Myung Yu, null Eun‐Gyoung Hong, null Sung Rae Cho, null Kyu Chang Won, null Yong Hyun Kim, null Seungjoon Oh, null Sung Hee Choi, null Gwanpyo Koh, null Wan Huh, null Su Young Kim, and null Kyong Soo Park
- Published
- 2023
5. Efficacy and safety of enavogliflozin versus dapagliflozin added to metformin plus gemigliptin treatment in patients with type 2 diabetes: A double-blind, randomized, comparator-active study: ENHANCE-D study
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Kyung-Soo Kim, Kyung Ah Han, Tae Nyun Kim, Cheol-Young Park, Jung Hwan Park, Sang Yong Kim, Yong Hyun Kim, Kee Ho Song, Eun Seok Kang, Chul Sik Kim, Gwanpyo Koh, Jun Goo Kang, Mi Kyung Kim, Ji Min Han, Nan Hee Kim, Ji Oh Mok, Jae Hyuk Lee, Soo Lim, Sang Soo Kim, Tae Ho Kim, Kyu Chang Won, Ki Young Lee, Jae Hyoung Cho, Ju Young Han, So Hun Kim, Jae Jin Nah, Hwa Rang Song, Si Eun Lee, and Sungrae Kim
- Subjects
Endocrinology ,Endocrinology, Diabetes and Metabolism ,Internal Medicine ,General Medicine - Published
- 2023
6. A double-blind, Randomized controlled trial on glucose-lowering EFfects and safety of adding 0.25 or 0.5 mg lobeglitazone in type 2 diabetes patients with INadequate control on metformin and dipeptidyl peptidase-4 inhibitor therapy: REFIND study
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Soree, Ryang, Sang Soo, Kim, Ji Cheol, Bae, Ji Min, Han, Su Kyoung, Kwon, Young Il, Kim, Il Seong, Nam-Goong, Eun Sook, Kim, Mi-Kyung, Kim, Chang Won, Lee, Soyeon, Yoo, Gwanpyo, Koh, Min Jeong, Kwon, Jeong Hyun, Park, and In Joo, Kim
- Subjects
Blood Glucose ,Glycated Hemoglobin ,Dipeptidyl-Peptidase IV Inhibitors ,Metformin ,Glucose ,Pyrimidines ,Treatment Outcome ,Diabetes Mellitus, Type 2 ,Double-Blind Method ,Humans ,Hypoglycemic Agents ,Drug Therapy, Combination ,Protease Inhibitors ,Thiazolidinediones ,Dipeptidyl-Peptidases and Tripeptidyl-Peptidases - Abstract
To compare the efficacy and safety of adding low-dose lobeglitazone (0.25 mg/day) or standard-dose lobeglitazone (0.5 mg/day) to patients with type 2 diabetes mellitus (T2DM) with inadequate glucose control on metformin and dipeptidyl peptidase (DPP4) inhibitor therapy.In this phase 4, multicentre, double-blind, randomized controlled, non-inferiority trial, patients with T2DM insufficiently controlled by metformin and DPP4 inhibitor combination therapy were randomized to receive either low-dose or standard-dose lobeglitazone. The primary endpoint was non-inferiority of low-dose lobeglitazone in terms of glycaemic control, expressed as the difference in mean glycated haemoglobin levels at week 24 relative to baseline values and compared with standard-dose lobeglitazone, using 0.5% non-inferiority margin.At week 24, the mean glycated haemoglobin levels were 6.87 ± 0.54% and 6.68 ± 0.46% in low-dose and standard-dose lobeglitazone groups, respectively (p = .031). The between-group difference was 0.18% (95% confidence interval 0.017-0.345), showing non-inferiority of the low-dose lobeglitazone. Mean body weight changes were significantly greater in the standard-dose group (1.36 ± 2.23 kg) than in the low-dose group (0.50 ± 1.85 kg) at week 24. The changes in HOMA-IR, lipid profile and liver enzyme levels showed no significant difference between the groups. Overall treatment-emergent adverse events (including weight gain, oedema and hypoglycaemia) occurred more frequently in the standard-dose group.Adding low-dose lobeglitazone to metformin and DPP4 inhibitor combination resulted in a non-inferior glucose-lowering outcome and fewer adverse events compared with standard-dose lobeglitazone. Therefore, low-dose lobeglitazone might be one option for individualized strategy in patients with T2DM.
- Published
- 2022
7. Clinical Evidence and Mechanisms of High-Protein Diet-Induced Weight Loss
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Jaecheol Moon and Gwanpyo Koh
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Weight loss ,medicine.medical_specialty ,High protein diet ,Endocrinology, Diabetes and Metabolism ,media_common.quotation_subject ,High-protein diet ,Review ,Satiation ,medicine.disease_cause ,lcsh:Diseases of the endocrine glands. Clinical endocrinology ,Orexigenic ,Internal medicine ,Ketogenesis ,medicine ,Resting energy expenditure ,Obesity ,media_common ,lcsh:RC648-665 ,business.industry ,Appetite ,Endocrinology ,Ghrelin ,medicine.symptom ,business ,Thermogenesis ,medicine.drug - Abstract
Several clinical trials have found that consuming more protein than the recommended dietary allowance not only reduces body weight (BW), but also enhances body composition by decreasing fat mass while preserving fat-free mass (FFM) in both low-calorie and standard-calorie diets. Fairly long-term clinical trials of 6–12 months reported that a high-protein diet (HPD) provides weight-loss effects and can prevent weight regain after weight loss. HPD has not been reported to have adverse effects on health in terms of bone density or renal function in healthy adults. Among gut-derived hormones, glucagon-like peptide-1, cholecystokinin, and peptide tyrosine-tyrosine reduce appetite, while ghrelin enhances appetite. HPD increases these anorexigenic hormone levels while decreasing orexigenic hormone levels, resulting in increased satiety signaling and, eventually, reduced food intake. Additionally, elevated diet-induced thermogenesis (DIT), increased blood amino acid concentration, increased hepatic gluconeogenesis, and increased ketogenesis caused by higher dietary protein contribute to increased satiety. The mechanism by which HPD increases energy expenditure involves two aspects: first, proteins have a markedly higher DIT than carbohydrates and fats. Second, protein intake prevents a decrease in FFM, which helps maintain resting energy expenditure despite weight loss. In conclusion, HPD is an effective and safe tool for weight reduction that can prevent obesity and obesity-related diseases. However, long-term clinical trials spanning more than 12 months should be conducted to further substantiate HPD effects.
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- 2020
8. Fasting and Postprandial Hyperglycemia: Their Predictors and Contributions to Overall Hyperglycemia in Korean Patients with Type 2 Diabetes
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Jaecheol Moon, Gwanpyo Koh, Jiyoung Kim, and Soyeon Yoo
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Adult ,Blood Glucose ,Male ,medicine.medical_specialty ,Waist ,endocrine system diseases ,Endocrinology, Diabetes and Metabolism ,030209 endocrinology & metabolism ,Type 2 diabetes ,lcsh:Diseases of the endocrine glands. Clinical endocrinology ,Gastroenterology ,Young Adult ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Endocrinology ,Internal medicine ,Republic of Korea ,medicine ,Humans ,Aged ,Retrospective Studies ,Glycemic ,Aged, 80 and over ,Glycated Hemoglobin ,lcsh:RC648-665 ,Triglyceride ,business.industry ,Blood Glucose Self-Monitoring ,Area under the curve ,nutritional and metabolic diseases ,Type 2 Diabetes Mellitus ,Fasting ,Middle Aged ,Postprandial Period ,Prognosis ,medicine.disease ,Postprandial ,Diabetes Mellitus, Type 2 ,chemistry ,Hyperglycemia ,Glycated hemoglobin A ,030220 oncology & carcinogenesis ,Female ,Original Article ,Glycated hemoglobin ,business ,Biomarkers ,Follow-Up Studies - Abstract
Background This study aimed to identify factors that affect fasting hyperglycemia (FHG) and postprandial hyperglycemia (PPG) and their contributions to overall hyperglycemia in Korean patients with type 2 diabetes mellitus (T2DM). Methods This was a retrospective study conducted on 194 Korean T2DM patients with 7-point self-monitoring blood glucose (SMBG) profiles plotted in 4 days in 3 consecutive months. We calculated the areas corresponding to FHG and PPG (area under the curve [AUC]FHG and AUCPPG) and contributions (%) in the graph of the 7-point SMBG data. The levels of glycated hemoglobin (HbA1c) were categorized by tertiles, and the contributions of FHG and PPG were compared. Results The relative contribution of FHG increased (44.7%±5.6%, 58.0%±4.4%, 66.5%±2.8%; PANOVA=0.002, PTREND l0.001), while that of PPG decreased (55.3%±5.5%, 42.0%±4.4%, 33.5%±2.8%; PANOVA=0.002, PTREND l0.001) with the elevated HbA1c. Multivariate analysis showed that HbA1c (β=0.615, Pl0.001), waist circumference (β=0.216, P=0.042), and triglyceride (β=0.121, P=0.048) had a significant association with AUCFHG. Only HbA1c (β=0.231, P=0.002) and age (β=0.196, P=0.009) was significantly associated with AUCPPG. Conclusion The data suggested that in Korean T2DM patients, FHG predominantly contributed to overall hyperglycemia at higher HbA1c levels, whereas it contributed to PPG at lower HbA1c levels. It is recommended that certain factors, namely age, degree of glycemic control, obesity, or triglyceride levels, should be considered when prescribing medications for T2DM patients.
- Published
- 2020
9. System χc- overexpression prevents 2-deoxy-d-ribose-induced β-cell damage
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Ju Young Bae, Gwanpyo Koh, Jaecheol Moon, and Soyeon Yoo
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0301 basic medicine ,chemistry.chemical_classification ,Reactive oxygen species ,Cystine ,Glutathione ,medicine.disease ,medicine.disease_cause ,Biochemistry ,Cell biology ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,0302 clinical medicine ,chemistry ,Physiology (medical) ,medicine ,Extracellular ,Cell damage ,030217 neurology & neurosurgery ,Intracellular ,Oxidative stress ,Cysteine - Abstract
Pancreatic β-cells are vulnerable to oxidative stress, which promotes β-cell failure in type 2 diabetes. System χc- is a sodium-independent, cystine/glutamate antiporter that mediates the exchange of extracellular l-cystine and intracellular l-glutamate. The import of l-cystine through this transporter is the rate-limiting step in the glutathione (GSH) biosynthesis pathway that plays a significant role in antioxidative defense. Previously, we reported that 2-deoxy-d-ribose (dRib) induces oxidative damage through GSH depletion in pancreatic β-cells. In the current study, we elucidated the mechanism underlying the oxidative stress-induced β-cell damage. We measured the intracellular l-[14C]cystine uptake, GSH content, reactive oxygen species (ROS) levels, cytotoxicity, and apoptosis in rat insulinoma cell line, RINm5F. Treatment of dRib decreased the intracellular l-[14C]cystine uptake and GSH content and increased the intracellular ROS levels, cytotoxicity, and apoptosis in a time- and dose-dependent manner. Conversely, 2-mercaptoethanol (2-ME), a cystine uptake enhancer, recovered the dRib-induced decrease in l-[14C]cystine uptake, GSH content, and cell viability in a Na+-independent manner. In the case of isolated islets, dRib dose-dependently decreased the intracellular l-[14C]cystine uptake and cell viability; however, dRib-induced cytotoxicity was completely recovered by adding N-acetyl cysteine (NAC). To confirm that system χc- mediates the oxidative stress-induced β-cell damage, we overexpressed xCT (the substrate-specific subunit of system χc-) using a lentiviral vector in RINm5F cells. Overexpression of xCT fully recovered the dRib-induced decrease in l-[14C]cystine uptake and GSH content and prevented the dRib-induced increase in ROS levels, cytotoxicity, and apoptosis. The overexpression of xCT showed a protective effect against dRib-induced oxidative damage in RINm5F cells. Our study showed that dRib depletes intracellular GSH content through inhibition of cystine transport via system χc- in β-cells.
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- 2020
10. Efficacy and Safety of High-Dose Atorvastatin in Moderate-to-High Cardiovascular Risk Postmenopausal Korean Women with Dyslipidemia
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Jaecheol Moon, Kyung-Wan Min, Gwanpyo Koh, Hyun Ho Shin, and Soyeon Yoo
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medicine.medical_specialty ,lcsh:Internal medicine ,lcsh:Diseases of the circulatory (Cardiovascular) system ,Endocrinology, Diabetes and Metabolism ,Atorvastatin ,Blood lipids ,Diabetes mellitus ,Internal medicine ,Internal Medicine ,Clinical endpoint ,Medicine ,Adverse effect ,lcsh:RC31-1245 ,medicine.diagnostic_test ,business.industry ,dyslipidemia ,koreans ,atorvastatin ,medicine.disease ,Clinical trial ,postmenopause ,lcsh:RC666-701 ,Original Article ,lipids (amino acids, peptides, and proteins) ,Cardiology and Cardiovascular Medicine ,business ,Lipid profile ,Dyslipidemia ,medicine.drug - Abstract
Objective: Postmenopausal women show a more atherogenic lipid profile and elevated cardiovascular risk compared to premenopausal women. The aim of this study was to investigate the efficacy and safety of high-dose atorvastatin on the improvement of the blood lipid profile of postmenopausal women in Korea. Methods: This study is a prospective, open-label, single-arm clinical trial that was conducted in 3 teaching hospitals. Postmenopausal women with a moderate-to-high cardiovascular risk, according to guidelines from the Korean Society of Lipid & Atherosclerosis, were enrolled. Participants were administered 20 mg of atorvastatin daily for the first 8 weeks, and if the targeted low-density lipoprotein cholesterol (LDL-C) level was not achieved, the dose was increased to 40 mg for the second 8 weeks. The primary endpoint was percentage change of LDL-C from baseline after 16 weeks of drug administration. Results: Forty-four women were enrolled, 28 of whom (75.6%) had diabetes mellitus. By the end of treatment period (16 weeks) all patients had achieved LDL-C target levels, with 33 (94.2%) of the participants achieving it after only 8 weeks of administration. After 16 weeks, LDL-C decreased by 45.8±16.7% (p
- Published
- 2020
11. The Change in Glucagon Following Meal Ingestion Is Associated with Glycemic Control, but Not with Incretin, in People with Diabetes
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Dongkyu Kim, Soyeon Yoo, and Gwanpyo Koh
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medicine.medical_specialty ,endocrine system ,Incretin ,030209 endocrinology & metabolism ,Glucagon ,Article ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Diabetes mellitus ,medicine ,Ingestion ,030304 developmental biology ,Glycemic ,0303 health sciences ,business.industry ,digestive, oral, and skin physiology ,Glucagon secretion ,General Medicine ,medicine.disease ,Glucagon-like peptide-1 ,glucagon-like peptide 1 ,glucose-dependent insulinotropic polypeptide ,Endocrinology ,Postprandial ,glucagon ,diabetes mellitus ,Medicine ,business ,hormones, hormone substitutes, and hormone antagonists - Abstract
Background: We aimed to investigate the changes in glucagon levels in people with diabetes after the ingestion of a mixed meal and the correlations of variation in glucagon levels with incretin and clinico-biochemical characteristics. Methods: Glucose, C-peptide, glucagon, intact glucagon-like peptide 1 (iGLP-1), and intact glucose-dependent insulinotropic polypeptide (iGIP) were measured in blood samples collected from 317 people with diabetes before and 30 min after the ingestion of a standard mixed meal. The delta (Δ) is the 30-min value minus the basal value. Results: At 30 min after meal ingestion, the glucagon level showed no difference relative to the basal value, whereas glucose, C-peptide, iGLP-1, and iGIP levels showed a significant increase. In univariate analysis, Δglucagon showed not only a strong correlation with HbA1c but also a significant correlation with fasting glucose, Δglucose, and estimated glomerular filtration rate. However, Δglucagon showed no significant correlations with ΔiGLP-1 and ΔiGIP. In the hierarchical multiple regression analysis, HbA1c was the only variable that continued to show the most significant correlation with Δglucagon. Conclusions: People with diabetes showed no suppression of glucagon secretion after meal ingestion. Patients with poorer glycemic control may show greater increase in postprandial glucagon level, and this does not appear to be mediated by incretin.
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- 2021
12. Postmeal increment in intact glucagon-like peptide 1 level, but not intact glucose-dependent insulinotropic polypeptide levels, is inversely associated with metabolic syndrome in patients with type 2 diabetes
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Soyeon Yoo, Eun-Jin Yang, Sang Ah Lee, and Gwanpyo Koh
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Male ,Risk ,medicine.medical_specialty ,Incretin ,030209 endocrinology & metabolism ,Gastric Inhibitory Polypeptide ,Disease ,Type 2 diabetes ,030204 cardiovascular system & hematology ,Incretins ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,Glucagon-Like Peptide 1 ,Internal medicine ,medicine ,Humans ,Ingestion ,Aged ,Metabolic Syndrome ,business.industry ,Type 2 Diabetes Mellitus ,General Medicine ,Middle Aged ,Postprandial Period ,medicine.disease ,Glucagon-like peptide-1 ,Cross-Sectional Studies ,Postprandial ,Diabetes Mellitus, Type 2 ,Cardiovascular Diseases ,Female ,Metabolic syndrome ,business - Abstract
Metabolic syndrome increases the risk of cardiovascular disease. Recently glucagon-like peptide 1 (GLP-1) agonists proved to be effective in preventing cardiovascular disease (CVD) in patients with type 2 diabetes. We investigated the association of blood incretin levels with metabolic syndrome in patients with type 2 diabetes.This is a cross-sectional study involving 334 people with type 2 diabetes. Intact GLP-1 (iGLP-1) and intact glucose-dependent insulinotropic polypeptide (iGIP) levels were measured in a fasted state and 30 min after ingestion of a standard mixed meal. Metabolic syndrome was diagnosed based on the criteria of the International Diabetes Federation.Two hundred twenty-five (69%) of the subjects have metabolic syndrome. The fasting iGLP-1 level was no different between groups. Thirty-min postprandial iGLP-1 was non-significantly lower in the subjects who had metabolic syndrome. Incremental iGLP-1 (ΔiGLP-1, the difference between 30-min postmeal and fasting iGLP-1 levels) was significantly lower in those with metabolic syndrome. There were no significant differences in fasting iGIP, postprandial iGIP, and ΔiGIP between groups. The ΔiGLP-1, but not ΔiGIP levels decreased significantly as the number of metabolic syndrome components increased. In hierarchical logistic regression analysis, the ΔiGLP-1 level was found to be a significant contributor to metabolic syndrome even after adjusting for other covariates.Taken together, the iGLP-1 increment in the 30 min after meal ingestion is inversely associated with metabolic syndrome in patients with type 2 diabetes. This suggests that postmeal iGLP-1 increment could be useful in assessing cardiovascular risk in type 2 diabetes.
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- 2017
13. System χ
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Soyeon, Yoo, Ju Young, Bae, Jaecheol, Moon, and Gwanpyo, Koh
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Oxidative Stress ,Amino Acid Transport System y+ ,Diabetes Mellitus, Type 2 ,Deoxyribose ,Insulin-Secreting Cells ,Ribose ,Animals ,Cystine ,Glutathione ,Rats - Abstract
Pancreatic β-cells are vulnerable to oxidative stress, which promotes β-cell failure in type 2 diabetes. System χ
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- 2019
14. 2122-P: System x(c)- Is a Key Molecule in Oxidative Stress-Induced ß-Cell Damage
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Soyeon Yoo, Gwanpyo Koh, Hyoun-Jung Chin, and Juyoung Bae
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0301 basic medicine ,chemistry.chemical_classification ,Reactive oxygen species ,Endocrinology, Diabetes and Metabolism ,Cystine ,030209 endocrinology & metabolism ,Oxidative phosphorylation ,Glutathione ,medicine.disease_cause ,Molecular biology ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,0302 clinical medicine ,chemistry ,Apoptosis ,Internal Medicine ,System X ,medicine ,Intracellular ,Oxidative stress - Abstract
Pancreatic β-cells are vulnerable to oxidative stress, which is related to β-cell failure in type 2 diabetes. System x(c)- is a sodium-independent cystine/glutamate antiporter that mediates the exchange of extracelluar L-cystine and intracellular L-glutamate. The import of L-cystine through this transporter is the limiting state of intracellular glutathione (GSH) synthesis that has a major role in defends against oxidative stress. Our previous study reported that 2-deoxy-D-ribose (dRib) induces oxidative damage through GSH depletion in pancreatic β-cells. The aim of the present study was to elucidate the mechanism underlying oxidative stress-induced β-cell damage. We measured intracellular L-[14C] cysteine uptake, GSH content and reactive oxygen species (ROS) levels, cytotoxicity and apoptosis in rat insulinoma cell line (RINm5F cells). Stimulation with dRib dose- and time-dependently decreased intracellular L-[14C] cystine uptake and GSH content and increased intracellular ROS levels, cytotoxicity and apoptosis. The addition of 2-mercaptoethanol (2-ME), a cystine uptake enhancer, sodium-independently recovered the dRib-induced decreases in L-[14C] cystine uptake, GSH content and cell viability. To determine clearly whether system x(c)- deficiency mediate the oxidative stress-induced β-cell damage, we overexpressed xCT, the substrate-specific subunit of the system x(c)-, by using a lentiviral vector in RINm5F cells. Overexpression of xCT fully recovered the dRib-induced decreases in L-[14C] cystine uptake and GSH content and prevented the dRib-induced ROS rises, cytotoxicity and apoptosis. In summary, overexpression of xCT showed protective effects against oxidative damage in RINm5F cells. It suggests that system x(c)- deficiency play a critical role in oxidative stress-induced β-cell damage. Disclosure S. Yoo: None. J. Bae: None. H. Chin: None. G. Koh: None.
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- 2019
15. Blood intact incretin levels are related to beta-cell function and glycemia in patients with type 2 diabetes
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Soyeon Yoo, Gwanpyo Koh, and Yeekyoung Ko
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medicine.medical_specialty ,Endocrinology ,business.industry ,Internal medicine ,medicine ,Incretin ,Beta-cell Function ,In patient ,Type 2 diabetes ,medicine.disease ,business - Published
- 2019
16. SUN-145 Factors Related to Blood Intact Incretin Levels in Patients with Type 2 Diabetes
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Ju Young Bae, Soyeon Yoo, Gwanpyo Koh, and Jae Cheol Moon
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Text mining ,business.industry ,Endocrinology, Diabetes and Metabolism ,Medicine ,Incretin ,In patient ,Type 2 diabetes ,business ,Bioinformatics ,medicine.disease ,Diabetes Mellitus and Glucose Metabolism ,Novel Approaches to Diabetes Management - Abstract
We performed this study to identify factors related to intact incretin levels in patients with type 2 diabetes (T2D).We cross-sectionally analyzed 336 patients with T2D. Intact glucagon-like peptide 1 (iGLP-1) and intact glucose-dependent insulinotropic polypeptide (iGIP) levels were measured in a fasted state and 30 min after ingestion of a standard mixed meal. The differences between 30 and 0 min iGLP-1 and iGIP levels were indicated as ΔiGLP-1 and ΔiGIP.After ingestion of a mixed meal, iGLP-1 (5.5±3.0 to 10.4±7.0 pmol/L; p
- Published
- 2019
17. Correlation of Glypican-4 Level with Basal Active Glucagon-Like Peptide 1 Level in Patients with Type 2 Diabetes Mellitus
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Sang Ah Lee, So Yeon Yoo, Suk Ju Cho, Sang Ouk Chin, and Gwanpyo Koh
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0301 basic medicine ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,030209 endocrinology & metabolism ,lcsh:Diseases of the endocrine glands. Clinical endocrinology ,Glypican 4 ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Endocrinology ,Insulin resistance ,Diabetes mellitus ,Glypicans ,Internal medicine ,medicine ,lcsh:RC648-665 ,biology ,business.industry ,Type 2 Diabetes Mellitus ,nutritional and metabolic diseases ,medicine.disease ,Glucagon-like peptide-1 ,Insulin receptor ,030104 developmental biology ,chemistry ,Active glucagon-like peptide 1 ,Clinical Study ,Homeostatic model assessment ,biology.protein ,Original Article ,Glycated hemoglobin ,business ,hormones, hormone substitutes, and hormone antagonists - Abstract
Background Previous studies have reported that glypican-4 (GPC4) regulates insulin signaling by interacting with insulin receptor and through adipocyte differentiation. However, GPC4 has not been studied with regard to its effects on clinical factors in patients with type 2 diabetes mellitus (T2DM). We aimed to identify factors associated with GPC4 level in T2DM. Methods Between January 2010 and December 2013, we selected 152 subjects with T2DM and collected serum and plasma into tubes pretreated with aprotinin and dipeptidyl peptidase-4 inhibitor to preserve active gastric inhibitory polypeptide (GIP) and glucagon-like peptide 1 (GLP-1). GPC4, active GLP-1, active GIP, and other factors were measured in these plasma samples. We performed a linear regression analysis to identify factors associated with GPC4 level. Results The subjects had a mean age of 58.1 years, were mildly obese (mean body mass index [BMI], 26.1 kg/m2), had T2DM of long-duration (mean, 101.3 months), glycated hemoglobin 7.5%, low insulin secretion, and low insulin resistance (mean homeostatic model assessment of insulin resistance [HOMA-IR], 1.2). Their mean GPC4 was 2.0±0.2 ng/mL. In multivariate analysis, GPC4 was independently associated with age (β=0.224, P=0.009), and levels of active GLP-1 (β=0.171, P=0.049) and aspartate aminotransferase (AST; β=–0.176, P=0.043) after being adjusted for other clinical factors. Conclusion GPC4 was independently associated with age, active GLP-1, and AST in T2DM patients, but was not associated with HOMA-IR and BMI, which are well known factors related to GPC4. Further study is needed to identify the mechanisms of the association between GPC4 and basal active GLP-1 levels.
- Published
- 2016
18. Rodent Models of Diet-induced Obesity
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Gwanpyo Koh
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medicine.medical_specialty ,Rodent ,biology ,business.industry ,030209 endocrinology & metabolism ,030229 sport sciences ,medicine.disease ,Obesity ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,biology.animal ,Internal medicine ,medicine ,business - Published
- 2016
19. Effectiveness and Safety of Adding Basal Insulin Glargine in Patients with Type 2 Diabetes Mellitus Exhibiting Inadequate Response to Metformin and DPP-4 Inhibitors with or without Sulfonylurea
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Bon Jeong Ku, Sin Gon Kim, Seung-Hwan Lee, Gwanpyo Koh, Young Min Cho, Yu Mi Kang, Sang-Wook Kim, Kee Ho Song, Jae Hyeon Kim, Chang Hee Jung, Tae Sun Park, Dol Mi Kim, Joong Yeol Park, and Byung Wan Lee
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Blood Glucose ,Male ,medicine.medical_specialty ,Insulin glargine ,endocrine system diseases ,medicine.drug_class ,Endocrinology, Diabetes and Metabolism ,030209 endocrinology & metabolism ,Clinical Diabetes & Therapeutics ,030204 cardiovascular system & hematology ,Hypoglycemia ,lcsh:Diseases of the endocrine glands. Clinical endocrinology ,Gastroenterology ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Diabetes mellitus ,medicine ,Humans ,Hypoglycemic Agents ,Adverse effect ,Glycemic ,Aged ,Glycated Hemoglobin ,Dipeptidyl-Peptidase IV Inhibitors ,lcsh:RC648-665 ,business.industry ,Body Weight ,Type 2 Diabetes Mellitus ,nutritional and metabolic diseases ,Diabetes mellitus, type 2 ,Middle Aged ,medicine.disease ,Sulfonylurea ,Metformin ,Sulfonylurea Compounds ,Treatment Outcome ,Drug Therapy, Combination ,Female ,Original Article ,Safety ,business ,medicine.drug - Abstract
Background We aimed to investigate the effectiveness and safety of adding basal insulin to initiating dipeptidyl peptidase-4 (DPP-4) inhibitor and metformin and/or sulfonylurea (SU) in achieving the target glycosylated hemoglobin (HbA1c) in patients with type 2 diabetes mellitus (T2DM). Methods This was a single-arm, multicenter, 24-week, open-label, phase 4 study in patients with inadequately controlled (HbA1c ≥7.5%) T2DM despite the use of DPP-4 inhibitor and metformin. A total of 108 patients received insulin glargine while continuing oral antidiabetic drugs (OADs). The primary efficacy endpoint was the percentage of subjects achieving HbA1c ≤7.0%. Other glycemic profiles were also evaluated, and the safety endpoints were adverse events (AEs) and hypoglycemia. Results The median HbA1c at baseline (8.9%; range, 7.5% to 11.1%) decreased to 7.6% (5.5% to 11.7%) at 24 weeks. Overall, 31.7% subjects (n=33) achieved the target HbA1c level of ≤7.0%. The mean differences in body weight and fasting plasma glucose were 1.2±3.4 kg and 56.0±49.8 mg/dL, respectively. Hypoglycemia was reported in 36 subjects (33.3%, 112 episodes), all of which were fully recovered. There was no serious AE attributed to insulin glargine. Body weight change was significantly different between SU users and nonusers (1.5±2.5 kg vs. -0.9±6.0 kg, P=0.011). Conclusion The combination add-on therapy of insulin glargine, on metformin and DPP-4 inhibitors with or without SU was safe and efficient in reducing HbA1c levels and thus, is a preferable option in managing T2DM patients exhibiting dysglycemia despite the use of OADs.
- Published
- 2018
20. Intracellular glutathione production, but not protein glycation, underlies the protective effects of captopril against 2-deoxy-D-ribose-induced β-cell damage
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Jiyoung Kim, Gwanpyo Koh, Sang Ah Lee, Eun Jin Yang, Soyeon Yoo, and Jong Hoon Hyun
- Subjects
Glycation End Products, Advanced ,Cancer Research ,Captopril ,Cell Survival ,medicine.medical_treatment ,Intracellular Space ,Apoptosis ,Pharmacology ,Biology ,Protective Agents ,medicine.disease_cause ,Biochemistry ,Cell Line ,chemistry.chemical_compound ,Glycation ,Cricetinae ,Insulin-Secreting Cells ,Genetics ,medicine ,Animals ,Insulin ,Buthionine sulfoximine ,Molecular Biology ,Cell damage ,Glutathione ,medicine.disease ,Molecular biology ,Rats ,Oxidative Stress ,Oncology ,chemistry ,Molecular Medicine ,Reactive Oxygen Species ,Oxidation-Reduction ,Intracellular ,Oxidative stress ,medicine.drug - Abstract
Our previous study reported that both oxidative stress and protein glycation were the principal mechanisms underlying 2‑deoxy‑D‑ribose (dRib)‑induced pancreatic β‑cell damage. The aim of the present study was to investigate the effects of captopril on dRib‑induced damage in pancreatic β‑cells, as well as to determine the mechanisms underlying these effects. Treatment with dRib increased the levels of cytotoxicity, apoptosis, and intracellular reactive oxygen species in Syrian hamster insulinoma HIT‑T15 cells; however, pretreatment with captopril significantly inhibited the effects of dRib. The intracellular levels of reduced and oxidized glutathione were depleted following treatment with dRib; however, these levels were restored following HIT‑T15 cell treatment with captopril. In rat islets, dRib stimulation suppressed the mRNA expression levels of insulin, and pancreatic and duodenal homeobox 1, as well as insulin content; however, these effects were dose‑dependently reversed by treatment with captopril. Treatment with buthionine sulfoximine, an inhibitor of intracellular glutathione biosynthesis, inhibited the protective effects of captopril on dRib‑mediated glutathione depletion and cytotoxicity in HIT‑T15 cells. Following incubation with albumin, dRib increased the formation of dicarbonyl and advanced glycation end products. Treatment with captopril did not inhibit the dRib‑induced increase in production of dicarbonyl and advanced glycation end products. In conclusion, treatment with captopril reversed dRib‑induced oxidative damage and suppression of insulin expression in β‑cells. The mechanism underlying the protective effects of captopril may involve increased intracellular glutathione production, rather than protein glycation.
- Published
- 2015
21. Apolipoprotein B Is Related to Metabolic Syndrome Independently of Low Density Lipoprotein Cholesterol in Patients with Type 2 Diabetes
- Author
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Seong Taeg Kim, Younghyup Lim, Sang Ah Lee, Shinhang Moon, Kiyoung Boo, Hyeyoung Jwa, Jae Cheol Moon, Gwanpyo Koh, Hye Mi Seo, Soyeon Yoo, Sang Ouk Chin, and Dahee Heo
- Subjects
medicine.medical_specialty ,Apolipoprotein B ,Endocrinology, Diabetes and Metabolism ,Type 2 diabetes ,lcsh:Diseases of the endocrine glands. Clinical endocrinology ,chemistry.chemical_compound ,Endocrinology ,High-density lipoprotein ,Internal medicine ,medicine ,National Cholesterol Education Program ,lcsh:RC648-665 ,Triglyceride ,biology ,business.industry ,Cholesterol ,nutritional and metabolic diseases ,Diabetes mellitus, type 2 ,medicine.disease ,Metabolic syndrome ,Cardiovascular diseases ,chemistry ,biology.protein ,Original Article ,lipids (amino acids, peptides, and proteins) ,Apolipoproetin B ,Glycated hemoglobin ,business - Abstract
Background: Increased low density lipoprotein cholesterol (LDL-C) level and the presence of metabolic syndrome (MetS) are important risk factors for cardiovascular disease (CVD) in type 2 diabetes mellitus (T2DM). Recent studies demonstrated apolipoprotein B (apoB), a protein mainly located in LDL-C, was an independent predictor of the development of CVD especially in patients with T2DM. The aim of this study was to investigate the relationship between apoB and MetS in T2DM patients. Methods: We analyzed 912 patients with T2DM. Fasting blood samples were taken for glycated hemoglobin, high-sensitivity Creactive protein, total cholesterol, triglyceride (TG), high density lipoprotein cholesterol, LDL-C, and apoB. MetS was defined by the modified National Cholesterol Education Program Adult Treatment Panel III criteria. We performed a hierarchical regression analysis with apoB as the dependent variable. Age, sex, the number of components of MetS and LDL-C were entered at model 1, the use of lipid-lowering medications at model 2, and the individual components of MetS were added at model 3. Results: Seventy percent of total subjects had MetS. ApoB level was higher in subjects with than those without MetS (104.5± 53.3 mg/dL vs. 87.7±33.7 mg/dL, P
- Published
- 2015
22. A relationship between serum potassium concentration and insulin resistance in patients with type 2 diabetes mellitus
- Author
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Gwanpyo Koh, Dae Ho Lee, Sang Ah Lee, and Hyun Woo Kim
- Subjects
Male ,medicine.medical_specialty ,Hyperkalemia ,Urology ,Potassium ,Glucose uptake ,chemistry.chemical_element ,Renal function ,Plasma renin activity ,Insulin resistance ,Internal medicine ,Diabetes mellitus ,medicine ,Humans ,business.industry ,Type 2 Diabetes Mellitus ,Middle Aged ,medicine.disease ,Cross-Sectional Studies ,Endocrinology ,Diabetes Mellitus, Type 2 ,chemistry ,Nephrology ,Female ,Insulin Resistance ,medicine.symptom ,business - Abstract
In patients with type 2 diabetes mellitus (DM), insulin-stimulated glucose uptake is impaired. However, the relationship between serum potassium concentration and insulin resistance is poorly defined. This study aimed to investigate the association between serum potassium concentration and insulin resistance in these patients. Between April 2009 and October 2012, 180 patients with type 2 DM were analyzed. Insulin resistance was estimated using the homeostasis model and assessment (HOMA) index; resistance was defined as an index value of >2. The association between serum potassium concentration and insulin resistance was analyzed using linear regression methods. The incidence of hyperkalemia was also evaluated during follow-up. Mean serum potassium concentration was 4.12 ± 0.47 mEq/l. The median HOMA index score was 2.1 (interquartile range 1.1–3.4). When the patients were compared based on insulin resistance, serum potassium concentration was higher in the patients with insulin resistance compared with the patients without (4.25 ± 0.48 vs. 4.09 ± 0.44 mEq/l, p = 0.015). The variables found to be the determinants of serum potassium concentration included female, renal function, serum sodium level, log aldosterone-to-plasma renin activity ratio, glycosylated hemoglobin, and log HOMA index. Over a mean follow-up period of 2.6 ± 1.1 years, 37 of 180 patients (21 %) experienced episodic hyperkalemia. Patients with insulin resistance experienced episodic hyperkalemia more frequently than those without. Serum potassium concentration is likely to be increased in the patients with poorly controlled type 2 DM with insulin resistance than in those without insulin resistance.
- Published
- 2015
23. F-FDG PET/CT Detects Late-onset Sialadenitis After Radioiodine Ablation Therapy
- Author
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Jin Ho Lee, Gwanpyo Koh, and Heesung Song
- Abstract
Sialadenitis is a common complication arising from radioactive iodine therapy. F-18-fluoro-2-deoxyglucose positronemission tomography/computed tomography (18F-FDGPET/CT) has been proposed to be useful in detecting not only amalignant lesion but also inflammatory changes. An 18F-FDG uptake pattern can vary according to inflammatorychanges, and the present study reports on a case of late-onset sialadenitis 3 years after the treatment, showing adiffuse and intense 18F-FDGuptakeon 18F-FDGPET/CT. To the best of our knowledge, this is the first report on such an18F-FDG pattern in late-onset sialadenitis after radioiodine therapy.
- Published
- 2016
24. Association between Serum Dipeptidyl Peptidase-4 Concentration and Obesity-Related Factors in Health Screen Examinees (J Obes Metab Syndr 2017;26:188-96)
- Author
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Gwanpyo Koh
- Subjects
Related factors ,medicine.medical_specialty ,lcsh:RC648-665 ,business.industry ,Endocrinology, Diabetes and Metabolism ,medicine.disease ,lcsh:Diseases of the endocrine glands. Clinical endocrinology ,Obesity ,Endocrinology ,Internal medicine ,medicine ,business ,Letter to the Editor ,Dipeptidyl peptidase-4 - Published
- 2018
25. Factors Related to Blood Intact Incretin Levels in Patients with Type 2 Diabetes Mellitus
- Author
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Eun Jin Yang, Gwanpyo Koh, and Soyeon Yoo
- Subjects
Blood Glucose ,Male ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Incretin ,Renal function ,030209 endocrinology & metabolism ,Gastric Inhibitory Polypeptide ,030204 cardiovascular system & hematology ,lcsh:Diseases of the endocrine glands. Clinical endocrinology ,Pathophysiology ,Incretins ,Eating ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Gastric inhibitory polypeptide ,Glucagon-Like Peptide 1 ,Diabetes mellitus ,Internal medicine ,Insulin Secretion ,medicine ,Humans ,Triglycerides ,Aged ,Creatinine ,lcsh:RC648-665 ,C-Peptide ,Triglyceride ,business.industry ,Type 2 Diabetes Mellitus ,Diabetes mellitus, type 2 ,Fasting ,Middle Aged ,medicine.disease ,Intact incretin ,Glucagon-like peptide-1 ,Cross-Sectional Studies ,Endocrinology ,chemistry ,Multivariate Analysis ,Original Article ,Female ,business - Abstract
Background We performed this study to identify factors related to intact incretin levels in patients with type 2 diabetes mellitus (T2DM). Methods We cross-sectionally analyzed 336 patients with T2DM. Intact glucagon-like peptide 1 (iGLP-1) and intact glucose-dependent insulinotropic polypeptide (iGIP) levels were measured in a fasted state and 30 minutes after ingestion of a standard mixed meal. The differences between 30 and 0 minute iGLP-1 and iGIP levels were indicated as ΔiGLP-1 and ΔiGIP. Results In simple correlation analyses, fasting iGLP-1 was positively correlated with glucose, C-peptide, creatinine, and triglyceride levels, and negatively correlated with estimated glomerular filtration rate. ΔiGLP-1 was positively correlated only with ΔC-peptide levels. Fasting iGIP showed positive correlations with glycosylated hemoglobin (HbA1c) and fasting glucose levels, and negative correlations with ΔC-peptide levels. ΔiGIP was negatively correlated with diabetes duration and HbA1c levels, and positively correlated with Δglucose and ΔC-peptide levels. In multivariate analyses adjusting for age, sex, and covariates, fasting iGLP-1 levels were significantly related to fasting glucose levels, ΔiGLP-1 levels were positively related to ΔC-peptide levels, fasting iGIP levels were related to fasting C-peptide levels, and ΔiGIP levels were positively related to ΔC-peptide and Δglucose levels. Conclusion Taken together, intact incretin levels are primarily related to C-peptide and glucose levels. This result suggests that glycemia and insulin secretion are the main factors associated with intact incretin levels in T2DM patients.
- Published
- 2019
26. Effect of Jeju Water on Blood Glucose Levels in Diabetic Patients: A Randomized Controlled Trial
- Author
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Hyun-Jung Han, Hyoun-Jung Chin, Okkyeong Hwang, Sang Ah Lee, Eun-Kyung Kang, Sok Young Kim, Eun-Jin Yang, Minkyoung Kim, Dae Ho Lee, and Gwanpyo Koh
- Subjects
medicine.medical_specialty ,Article Subject ,Population ,Gastroenterology ,law.invention ,chemistry.chemical_compound ,Tap water ,Randomized controlled trial ,law ,Internal medicine ,Diabetes mellitus ,medicine ,In patient ,education ,Glycemic ,education.field_of_study ,Traditional medicine ,business.industry ,Liter ,lcsh:Other systems of medicine ,lcsh:RZ201-999 ,medicine.disease ,Complementary and alternative medicine ,chemistry ,Glycated hemoglobin ,business ,Research Article - Abstract
Jeju water is the groundwater of Jeju Island, a volcanic island located in Republic of Korea. We investigated whether Jeju water improved glycemic control in patients with diabetes. This was a 12-week single-center, double-blind, randomized, and controlled trial. The subjects daily drank a liter of one of three kinds of water: two Jeju waters (S1 and S2) and Seoul tap water (SS). The primary outcome was the proportion of patients in the per-protocol (PP) population achieving glycated hemoglobin (HbA1c)<7.0% at week 12. In total, 196 patients were randomized and analyzed in the intention-to-treat (ITT) population (66 consuming S1, 63 consuming S2, and 67 consuming SS); 146 patients were considered in the PP population. There were no significant differences in the primary outcomes of the groups consuming S1, S2, or SS. However, the percentage of patients achieving HbA1c<8% was significantly higher in the S2 group than in the SS group. In the ITT population, the 12-week HbA1c and fructosamine levels were lower in the S1 group than in the SS group and the 4-, 8-, and 12-week fructosamine levels were lower in the S2 group than in the SS group. Although we failed to achieve the primary outcome, it is possible that the Jeju waters improve glycemic control compared with the Seoul tap water in diabetic patients.
- Published
- 2013
27. Correlations between Glucagon Stimulated C-peptide Levels and Microvascular Complications in Type 2 Diabetes Patients
- Author
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Keun Young Park, Youn-Zoo Cho, Gwanpyo Koh, Dae Ho Lee, Ji Young Kim, Dong-Mee Lim, Byung Joon Kim, and Hye-Jin Yoon
- Subjects
medicine.medical_specialty ,Complications ,Microvascular complications ,lcsh:RC648-665 ,business.industry ,Endocrinology, Diabetes and Metabolism ,Type 2 Diabetes Mellitus ,Diabetes mellitus, type 2 ,Type 2 diabetes ,medicine.disease ,Glucagon ,lcsh:Diseases of the endocrine glands. Clinical endocrinology ,Confidence interval ,Nephropathy ,Basal C-peptide ,Basal (phylogenetics) ,Endocrinology ,Diabetes mellitus ,Internal medicine ,medicine ,Original Article ,Glucagon stimulation test ,business ,Retinopathy ,Stimulated C-peptide - Abstract
Background This study aimed to investigate whether stimulated C-peptide is associated with microvascular complications in type 2 diabetes mellitus (DM). Methods A cross-sectional study was conducted in 192 type 2 diabetic patients. Plasma basal C-peptide and stimulated C-peptide were measured before and 6 minutes after intravenous injection of 1 mg glucagon. The relationship between C-peptide and microvascular complications was statistically analyzed. Results In patients with retinopathy, basal C-peptide was 1.9±1.2 ng/mL, and stimulated C-peptide was 2.7±1.6 ng/mL; values were significantly lower compared with patients without retinopathy (P=0.031 and P=0.002, respectively). In patients with nephropathy, basal C-peptide was 1.6±0.9 ng/mL, and stimulated C-peptide was 2.8±1.6 ng/mL; values were significantly lower than those recorded in patients without nephropathy (P=0.020 and P=0.026, respectively). Stimulated C-peptide level was associated with increased prevalence of microvascular complications. Age-, DM duration-, and hemoglobin A1c-adjusted odds ratios for retinopathy in stimulated C-peptide value were 4.18 (95% confidence interval [CI], 1.40 to 12.51) and 3.35 (95% CI, 1.09 to 10.25), respectively. The multiple regression analysis between nephropathy and C-peptide showed that stimulated C-peptide was statistically correlated with nephropathy (P=0.03). Conclusion In patients with type 2 diabetes, the glucagon stimulation test was a relatively simple method of short duration for stimulating C-peptide response. Stimulated C-peptide values were associated with microvascular complications to a greater extent than basal C-peptides.
- Published
- 2012
28. A Case of Painful Hashimoto Thyroiditis that Mimicked Subacute Thyroiditis
- Author
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Sang Ah Lee, Jeongwon Lee, Dae Ho Lee, Hye Mi Seo, Gwanpyo Koh, Jo Heon Kim, Jaeseok Bae, and Miyeon Kim
- Subjects
Hashimoto thyroiditis ,Pathology ,medicine.medical_specialty ,endocrine system ,Goiter ,medicine.diagnostic_test ,endocrine system diseases ,business.industry ,Thyroid ,General Engineering ,Levothyroxine ,Case Report ,medicine.disease ,Thyroid disorder ,Fine-needle aspiration ,medicine.anatomical_structure ,Biopsy ,Medicine ,Subacute thyroiditis ,business ,Subclinical infection ,medicine.drug - Abstract
Hashimoto thyroiditis (HT) is an autoimmune thyroid disorder that usually presents as a diffuse, nontender goiter, whereas subacute thyroiditis (SAT) is an uncommon disease that is characterized by tender thyroid enlargement, transient thyrotoxicosis, and an elevated erythrocyte sedimentation rate (ESR). Very rarely, patients with HT can present with painful, tender goiter or fever, a mimic of SAT. We report a case of painful HT in a 68-year-old woman who presented with pain and tenderness in a chronic goiter. Her ESR was definitely elevated and her thyroid laboratory tests suggested subclinical hypothyroidism of autoimmune origin. (99m)Tc pertechnetate uptake was markedly decreased. Fine needle aspiration biopsy revealed reactive and polymorphous lymphoid cells and occasional epithelial cells with Hurthle cell changes. Her clinical symptoms showed a dramatic response to glucocorticoid treatment. She became hypothyroid finally and is now on levothyroxine therapy.
- Published
- 2012
29. Resveratrol improves insulin signaling in a tissue-specific manner under insulin-resistant conditions only: in vitro and in vivo experiments in rodents
- Author
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Doek-Bae Park, Hyun Ju Hong, Dae Ho Lee, Eun-Jin Yang, Chang Hoon Han, Jian Guan, Young Jae Lee, Dong Geon Kim, Gwanpyo Koh, and Wonyoung Kang
- Subjects
Male ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Blotting, Western ,Anti-Inflammatory Agents ,Mice, Obese ,White adipose tissue ,AMP-Activated Protein Kinases ,Resveratrol ,Protein degradation ,Real-Time Polymerase Chain Reaction ,Mice ,chemistry.chemical_compound ,Endocrinology ,3T3-L1 Cells ,Internal medicine ,Stilbenes ,Adipocytes ,medicine ,Animals ,Insulin ,Obesity ,Phosphorylation ,Cells, Cultured ,Inflammation ,biology ,Tyrosine phosphorylation ,Dietary Fats ,Mice, Inbred C57BL ,Nitric oxide synthase ,Insulin receptor ,Liver ,chemistry ,Culture Media, Conditioned ,biology.protein ,Insulin Resistance ,Signal Transduction - Abstract
Resveratrol (RSV) has various metabolic effects, especially with relatively high-dose therapy. However, the ability of RSV to modulate insulin signaling has not been completely evaluated. Here, we determined whether RSV alters insulin signaling in insulin-responsive cells and tissues. The effects of RSV on insulin signaling in 3T3-L1 adipocytes under both insulin-sensitive and insulin-resistant states and in insulin-sensitive tissues of high fat-fed diet-induced obese (DIO) mice were investigated. Insulin-stimulated insulin receptor substrate-1 tyrosine phosphorylation (Y612) was suppressed in RSV-treated adipocytes compared with untreated adipocytes, as was the insulin-stimulated Akt phosphorylation (Ser473). However, under an insulin-resistant condition that was made by incubating 3T3-L1 adipocytes in the conditioned medium from lipopolysaccharide-stimulated LAW264.7 cells, RSV reduced inducible nitric oxide synthase expression and IκBα protein degradation and improved insulin-stimulated Akt phosphorylation (Ser473). In DIO mice, relatively low-dose RSV (30 mg/kg daily for 2 weeks) therapy lowered fasting blood glucose level and serum insulin, increased hepatic glycogen content, and ameliorated fatty liver without change in body weight. The insulin-stimulated Akt phosphorylation was decreased in the liver and white adipose tissue of DIO mice, but it was completely normalized by RSV treatment. However, in the skeletal muscle of DIO mice, insulin signaling was not improved by RSV treatment, whereas the phosphorylation of adenosine monophosphate-activated protein kinase α (Thr172) was improved by it. Our results show that RSV enhances insulin action only under insulin-resistant conditions and suggest that the effect of RSV may depend on the type of tissue being targeted and its metabolic status.
- Published
- 2012
30. Basal C-peptide Level as a Surrogate Marker of Subclinical Atherosclerosis in Type 2 Diabetic Patients
- Author
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Sung-Tae Kim, Kang-Woo Lee, In-Geol Song, Youn-Zoo Cho, Byung Joon Kim, Gwanpyo Koh, Dong-Mee Lim, Keun Young Park, Jang-Han Jung, and Dae Ho Lee
- Subjects
Pathology ,medicine.medical_specialty ,endocrine system diseases ,Endocrinology, Diabetes and Metabolism ,lcsh:Diseases of the endocrine glands. Clinical endocrinology ,chemistry.chemical_compound ,Basal (phylogenetics) ,Diabetes mellitus ,Internal medicine ,medicine ,lcsh:RC648-665 ,C-peptide ,Cell growth ,Surrogate endpoint ,business.industry ,Type 2 Diabetes Mellitus ,medicine.disease ,Atherosclerosis ,Metabolic syndrome ,Endocrinology ,chemistry ,Subclinical atherosclerosis ,Original Article ,business ,Carotid artery - Abstract
Background Recent studies have revealed that C-peptide induces smooth muscle cell proliferation and causes human atherosclerotic lesions in diabetic patients. The present study was designed to examine whether the basal C-peptide levels correlate with cardiovascular risk in type 2 diabetes mellitus (T2DM) patients. Methods Data was obtained from 467 patients with T2DM from two institutions who were followed for four years. The medical findings of all patients were reviewed, and patients with creatinine >1.4 mg/dL, any inflammation or infection, hepatitis, or type 1 DM were excluded. The relationships between basal C-peptide and other clinical values were statistically analyzed. Results A simple correlation was found between basal C-peptide and components of metabolic syndrome (MS). Statistically basal C-peptide levels were significantly higher than the three different MS criteria used in the present study, the Adult Treatment Panel III (ATP III) of the National Cholesterol Education Program's (NCEP's), World Health Organization (WHO), and the International Diabetes Federation (IDF) criteria (NCEP-ATP III, P=0.001; IDF, P
- Published
- 2011
31. Selection of the optimal hypoglycemic agent for type 2 diabetes: based on the 2009 consensus statement of the American Diabetes Association and the European Association for the Study of Diabetes
- Author
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Gwanpyo Koh
- Abstract
The management of hyperglycemia, the hallmark metabolic abnormality associated with type 2 diabetes, has taken center stage in the treatment of diabetes. The development of new classes of blood glucose-lowering medications to supplement the older therapies has increased the number of treatment options available for type 2 diabetes. The increased number of choices available to practitioners and patients has heightened uncertainty regarding the most appropriate means of treating this widespread disease. The ADA/EASD consensus algorithm for the medical management of type 2 diabetes was published in January 2009. I introduced the consensus approach to the management of hyperglycemia to help guide health care providers in choosing the most appropriate interventions for their patients with type 2 diabetes.
- Published
- 2009
32. Clinical application of Exenatide for type 2 diabetes
- Author
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Gwanpyo Koh
- Abstract
Exenatide is the first in a new class of compounds, which possess similar activity to the naturally-occurring hormone glucagon-like peptide-1 (GLP-1. In three phase Ⅲ trials in patients with type 2 diabetes mellitus (T2DM). who have Inadequate glycaemic control despite receiving treatment with metformin and/ or sulfonylurea, the addition of exenatide twice daily significantly reduced glycated haemoglobin ( ≤ 1 %), and fasting and postprandial plasma glucose and was associated with progressive and significant bodyweight reduction from baseline for up to 2 years, Nausea (about 40%) was the most commonly reported adverse event in the combined exenatide groups. The addition of exenatide also improved glycemic control in a small population with T2DM receiving thiazolidinedione. The glycaemic control with exenatide was similar to that achieved with insulin glargine or biphasic insulin aspart. However, the insulin doses were well below doses used in recent studies. In a head-to-head clinical trial, exenatide once-weekly caused greater improvements in glycemic control and was better tolerated than exenatide twice daily. On the basis of the data, adjunctive therapy with exenatide is a valuable therapeutic option in obese patients with T2DM requiring moderate improvements in glycaemic control despite treatment with metformin and/or a sulfonylurea, In addition, exenatide once-weekly is a promising development candidate for the treatment of T2DM.
- Published
- 2009
33. Mechanism Underlying 2-Deoxy- D -Ribose-Induced Oxidative Damage in a Pancreatic Beta-Cell Line
- Author
-
Eun-Jin Yang, Gwanpyo Koh, and Soyeon Yoo
- Subjects
chemistry.chemical_compound ,Biochemistry ,Chemistry ,Apoptosis ,Physiology (medical) ,Ribose ,Extracellular ,Cystine ,Glutathione ,Viability assay ,Beta cell ,Intracellular - Abstract
2-Deoxy- d -ribose (dRib) is known to induce oxidative damage and apoptosis by depleting GSH content in several types of cells. However, little is known about how dRib depletes intracellular GSH content. We hypothesized that dRib would deplete GSH content through inhibition of cystine uptake via system χc-. HIT-T15 cells were incubated with various concentrations of dRib, 2-mercaptoethanol (2-ME), Sulfasalazine (SASP), and homocysteic acid (HCA). We measured intracellular uptake of l -[14C]cystine, GSH content, and cell viability. Stimulation with dRib dose- and time-dependently decreases intracellular l -[14C]cystine uptake and GSH content. The addition of 2-ME, a cystine uptake enhancer, fully recovered the dRib-induced decreases in l -[14C]cystine uptake, GSH content, and cell viability. The 2-ME promoted the l -[14C]cystine uptake even in the absence of extracellular Na+, probably suggesting the involvement of the system χc-. SASP and HCA, system χc- inhibitors, significantly reduced l -[14C]cystine uptake and GSH content like dRib did, and 2-ME also restored the reductions. These findings suggest that dRib depletes intracellular GSH content through inhibition of cystine transport, and this inhibition may be mediated by system χc-. Additional experiments using a gene overexpression technique is necessary to further clarify the mechanism.
- Published
- 2017
34. A case of exogenous corticosteroid-induced Kaposi's sarcoma that developed after a cure of endogenous hypercortisolism
- Author
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Shinhang Moon, Changlim Hyun, Sang-Ouk Chin, Soyeon Yoo, Gwanpyo Koh, and Sang-Ah Lee
- Subjects
Male ,medicine.medical_specialty ,medicine.drug_class ,Hormone Replacement Therapy ,medicine.medical_treatment ,Prednisolone ,Pharmaceutical Science ,Pharmacy ,Toxicology ,Gastroenterology ,Cushing syndrome ,Adrenal Cortex Hormones ,Internal medicine ,medicine ,Adrenal insufficiency ,Humans ,Pharmacology (medical) ,Kaposi's sarcoma ,Cushing Syndrome ,Sarcoma, Kaposi ,Aged ,Skin ,Pharmacology ,business.industry ,Adrenalectomy ,medicine.disease ,Endocrinology ,Corticosteroid ,Sarcoma ,business ,Glucocorticoid ,medicine.drug - Abstract
Case Kaposi’s sarcoma (KS) is a malignant vascular tumor that occurs commonly in patients with acquired immunodeficiency syndrome. KS associated with Cushing’s syndrome (CS) is unusual, especially in endogenous CS. Here, we report a case of KS associated with glucocorticoid-replacement therapy after surgical treatment for adrenal CS. A 70-year-old man presented with symptoms and signs of CS with a left adrenal mass. Adrenal CS was confirmed by biochemical studies. After left adrenalectomy, he took oral prednisolone (15 mg/day) to prevent adrenal insufficiency. Ten weeks later, numerous raised purple plaques on the lower extremities were newly detected. The biopsy findings were compatible with KS, but anti-HIV antibodies were negative. After withdrawal of glucocorticoid therapy, the skin lesions regressed completely. Conclusion In this case, KS developed after the use of exogenous corticosteroid but not during endogenous hypercortisolism. This finding suggests that endogenous and exogenous corticosteroid play different roles in the development of KS.
- Published
- 2015
35. Obesity and Left Ventricular Diastolic Dysfunction
- Author
-
Gwanpyo Koh
- Subjects
03 medical and health sciences ,medicine.medical_specialty ,0302 clinical medicine ,business.industry ,Internal medicine ,medicine ,Cardiology ,030209 endocrinology & metabolism ,Left ventricular diastolic dysfunction ,030204 cardiovascular system & hematology ,business ,medicine.disease ,Obesity - Published
- 2016
36. Effect of Scutellariae Radix Extract on the High Glucose-Induced Apoptosis in Cultured Vascular Endothelial Cells
- Author
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Jinwoo Kim, Cheol-Young Park, Jeong Taek Woo, Sung Woon Kim, Gwanpyo Koh, Young-Min Ahn, Kwang Sik Suh, Young Seol Kim, Yeon Ho Nam, Nam Jae Kim, and Seungjoon Oh
- Subjects
Programmed cell death ,Endothelium ,Scutellaria ,Pharmaceutical Science ,Apoptosis ,Pharmacology ,Biology ,Plant Roots ,medicine ,Animals ,Cells, Cultured ,TUNEL assay ,Dose-Response Relationship, Drug ,Plant Extracts ,Cell growth ,General Medicine ,Endothelial stem cell ,Glucose ,medicine.anatomical_structure ,Biochemistry ,Cell culture ,Cattle ,Endothelium, Vascular ,Blood vessel - Abstract
Endothelial cell apoptosis has been postulated as the initial trigger of the progression of microvascular disease in patients with diabetes mellitus. To investigate the role of Scutellariae radix extract, we examined its effect on the endothelial cell proliferation using the [3H]-thymidine incorporation method. Scutellariae radix extract significantly stimulated endothelial cell proliferation in a dose-dependent manner. We focused on the protective action of Scutellariae radix extract on the endothelial cell apoptosis induced by high glucose concentrations. Determination of endothelial cell apoptosis was performed using DNA gel electrophoresis, terminal deoxynuclotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay, and an ELISA kit. Exposure of vascular endothelial cell to high glucose (16.7 mM) for 72 h resulted in a significant increase in apoptosis, compared with the normal glucose concentrations (5.5 mM). Scutellariae radix extract inhibited high glucose-induced endothelial cell apoptosis. This result suggests that Scutellariae radix extract may contribute to antiapoptotic action against vascular endothelial cells, resulting in a beneficial effect in preventing diabetes-associated microvascular complications.
- Published
- 2003
37. Hypoglycemia at admission in patients with acute myocardial infarction predicts a higher 30-day mortality in patients with poorly controlled type 2 diabetes than in well-controlled patients
- Author
-
Seok Kyu Oh, Sang Ah Lee, Kyeong Ho Yun, Kamir, Chung Gu Cho, Hyo-Soo Kim, Chong Jin Kim, Young Jo Kim, Suk Ju Cho, Myeong Chan Cho, Gwanpyo Koh, KorMI Registry, Youngkeun Ahn, Myung Ho Jeong, Ha Young Kim, Dae Ho Lee, and Jeong Mi Lee
- Subjects
Research design ,Blood Glucose ,Male ,medicine.medical_specialty ,Time Factors ,Endocrinology, Diabetes and Metabolism ,Myocardial Infarction ,Type 2 diabetes ,Hypoglycemia ,Patient Admission ,Diabetes mellitus ,Internal medicine ,Republic of Korea ,Internal Medicine ,medicine ,Humans ,In patient ,Myocardial infarction ,Registries ,Intensive care medicine ,Aged ,Advanced and Specialized Nursing ,Glycated Hemoglobin ,business.industry ,Middle Aged ,medicine.disease ,Prognosis ,Diabetes Mellitus, Type 2 ,Hyperglycemia ,Observational study ,Female ,Myocardial infarction diagnosis ,business ,Diabetic Angiopathies - Abstract
OBJECTIVE We aimed to evaluate the association between hypoglycemia at admission and 30-day mortality in patients with acute myocardial infarction (AMI) and to determine whether these associations differed according to diabetes-control status in AMI patients with diabetes. RESEARCH DESIGN AND METHODS We analyzed the prognostic significance of hypoglycemia and hyperglycemia in 34,943 AMI patients with or without type 2 diabetes from two AMI registries: the Korea Acute Myocardial Infarction Registry (KAMIR) and the Korea Working Group on Myocardial Infarction (KorMI). RESULTS The patients were divided into five groups according to serum-glucose levels at admission: CONCLUSIONS These data suggest that hypoglycemia at admission affects clinical outcomes differently in AMI patients with type 2 diabetes depending on the diabetes-control status.
- Published
- 2014
38. Alpha-lipoic acid treatment reverses 2-deoxy-D-ribose-induced oxidative damage and suppression of insulin expression in pancreatic beta-cells
- Author
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Dae Ho Lee, Gwanpyo Koh, Eun-Jin Yang, Sang Ah Lee, and Minkyoung Kim
- Subjects
medicine.medical_specialty ,Alpha-Lipoic Acid ,medicine.medical_treatment ,Pharmaceutical Science ,Stimulation ,medicine.disease_cause ,Antioxidants ,Rats, Sprague-Dawley ,chemistry.chemical_compound ,Internal medicine ,Insulin-Secreting Cells ,medicine ,Animals ,Insulin ,RNA, Messenger ,Enzyme Inhibitors ,Cytotoxicity ,Buthionine Sulfoximine ,Pharmacology ,Homeodomain Proteins ,Dose-Response Relationship, Drug ,Thioctic Acid ,Deoxyribose ,General Medicine ,Glutathione ,Rats ,Oxidative Stress ,Endocrinology ,Glucose ,chemistry ,Apoptosis ,Oxidation-Reduction ,Oxidative stress ,Intracellular - Abstract
We investigated whether α-lipoic acid (LA) could prevent 2-deoxy-D-ribose (dRib)-induced oxidative damage and suppression of insulin expression in pancreatic β-cells. Stimulation with 50 mM dRib elevated cytotoxicity, apoptosis and intracellular reactive oxygen species (ROS) levels in HIT-T15 cells, but pretreatment with LA significantly reversed the dRib-induced changes. LA directly scavenged hydroxyl radicals generated by a Fenton reaction. Intracellular reduced glutathione (GSH) and oxidized glutathione (GSSG) were depleted by stimulation with dRib but levels were restored by addition of LA to HIT-T15 cells. However, the GSH/GSSG ratio was unchanged by LA treatment. In rat islets, stimulation with 10 mM dRib for 6 h suppressed expression of insulin and pancreatic and duodenal homeobox 1 mRNA and decreased insulin content, but these were dose-dependently reversed when LA was added. Treatment with l-buthionine-sulfoximine, an inhibitor of intracellular glutathione biosynthesis, completely abolished the protective effects of LA on dRib-mediated glutathione depletion and cytotoxicity in HIT-T15 cells. In summary, LA reversed the dRib-induced oxidative damage and suppression of insulin expression in β-cells. Enhanced intracellular total glutathione production, rather than the scavenging of ROS, is possibly the mechanism for the protective effect of LA.
- Published
- 2013
39. CD26/DPP4 levels in peripheral blood and T cells in patients with type 2 diabetes mellitus
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Gwanpyo Koh, Jin Seok Kim, Young Ree Kim, Sang Ah Lee, Doek Bae Park, Sun Hyung Kim, Dae Ho Lee, Byung-Chul Oh, Sang Taek Heo, Eun Jin Yang, Sung Ha Kang, and Eun-Jeong Kwon
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Adult ,Blood Glucose ,Male ,medicine.medical_specialty ,endocrine system diseases ,Endocrinology, Diabetes and Metabolism ,T cell ,Dipeptidyl Peptidase 4 ,T-Lymphocytes ,Clinical Biochemistry ,Context (language use) ,Biochemistry ,Flow cytometry ,Endocrinology ,Internal medicine ,Diabetes mellitus ,medicine ,Humans ,Dipeptidyl peptidase-4 ,medicine.diagnostic_test ,business.industry ,Biochemistry (medical) ,nutritional and metabolic diseases ,Type 2 Diabetes Mellitus ,Middle Aged ,medicine.disease ,Metformin ,medicine.anatomical_structure ,Diabetes Mellitus, Type 2 ,Female ,Thiazolidinediones ,business ,CD8 ,medicine.drug - Abstract
Context: Dipeptidyl peptidase 4 (CD26/DPP4) is expressed on blood T cells and also circulates in a soluble form (sCD26/DPP4). Objective: We aimed to evaluate blood T cell and circulating CD26/DPP4 and its association with metabolic parameters in patients with type 2 diabetes mellitus (T2DM). Designs: We measured CD26/DPP4 expression (percentage of CD26+ cells using flow cytometry) on CD4+ and CD8+ T cells, serum CD26/DPP4 level and activity, and various metabolic parameters in T2DM patients not on DPP4 inhibitor therapy (n = 148). Nondiabetic subjects (n = 50) were included as a control group. Results: Compared with the healthy controls, CD26/DPP4 expression on CD4+ T cells and CD8+ T cells was higher in T2DM patients. Serum CD26/DPP4 levels and enzymatic activities were also higher in patients with T2DM than in the control group only when metformin and/or thiazolidinedione-treated T2DM patients were excluded; metformin and/or thiazolidinedione-treated T2DM patients had lower values compared with other T2DM patients. Various parameters in T2DM patients were related to CD26/DPP4 expression on the T cells (hemoglobin A1c), serum sCD26/DPP4 (hemoglobin A1c and insulin resistance assessed by updated homeostasis model assessment), and serum CD26/DPP4 activity (insulin resistance assessed by updated homeostasis model assessment, γ-glutamyl transferase, and alanine aminotransferase) by multivariate analyses. After active glucose control for 12 weeks in drug-naive T2DM patients (n = 50), CD26/DPP4 expression on blood T cells was significantly decreased. Conclusions: Our results suggest that the CD26/DPP4 level on blood T cells was associated with glucose control status in patients with T2DM.
- Published
- 2013
40. Thyroid Volume Measured by99mTc-Pertechnetate Scintigraphy and Its Relationship with Clinical Parameters in Korean Patients with Autoimmune Thyroiditis
- Author
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Young Hwan Kim, Seong Man Lee, Gwanpyo Koh, Sang Ah Lee, and Soyeon Yoo
- Subjects
medicine.medical_specialty ,Pathology ,medicine.diagnostic_test ,business.industry ,Thyroid ,030209 endocrinology & metabolism ,99mtc pertechnetate ,Scintigraphy ,medicine.disease ,030218 nuclear medicine & medical imaging ,Autoimmune thyroiditis ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,Endocrinology ,Internal medicine ,medicine ,business ,Antithyroglobulin antibody - Published
- 2016
41. Gliclazide Does Not Fully Prevent 2-Deoxy-D-Ribose-Induced Oxidative Damage Because It Does Not Restore Glutathione Content in a Pancreatic β-Cell Line
- Author
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Dae Ho Lee, Gwanpyo Koh, Minkyoung Kim, and Eun-Jin Yang
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Aging ,Programmed cell death ,Antioxidant ,Article Subject ,Cell Survival ,medicine.medical_treatment ,Apoptosis ,Pharmacology ,medicine.disease_cause ,Biochemistry ,Cell Line ,Acetylcysteine ,chemistry.chemical_compound ,Cricetinae ,Insulin-Secreting Cells ,medicine ,Animals ,Hypoglycemic Agents ,Gliclazide ,Drug Interactions ,lcsh:QH573-671 ,chemistry.chemical_classification ,Reactive oxygen species ,lcsh:Cytology ,Deoxyribose ,Hydroxyl Radical ,Cell Biology ,General Medicine ,Glutathione ,Oxidative Stress ,chemistry ,Reactive Oxygen Species ,Oxidative stress ,medicine.drug ,Research Article - Abstract
We compared the effects of gliclazide, an antidiabetic agent with antioxidant properties, andN-acetyl-L-cysteine (NAC), a glutathione precursor, in protecting against 2-deoxy-D-ribose- (dRib-) induced oxidative damage in HIT-T15 cells. Using trypan blue staining and flow cytometry with annexin V/PI staining, gliclazide treatment slightly reversed dRib-induced cell death and apoptosis, and NAC treatment markedly reduced both measures. Likewise, flow cytometry using DHR 123 staining showed that the levels of dRib-induced reactive oxygen species (ROS) were partially suppressed by gliclazide and completely inhibited by NAC. Using electron spin resonance spectrometry, gliclazide and NAC scavenged hydroxyl radicals generated by Fenton reaction to a similar degree in a cell-free system. NAC, but not gliclazide, completely restored the intracellular glutathione depleted by dRib using monochlorobimane fluorescence and glutathione assays. Thus, gliclazide treatment suppressed dRib-induced oxidative damage in HIT-T15 cells less than NAC did because gliclazide did not restore the intracellular glutathione content as effectively as NAC. In addition, the elevation of intracellular glutathione rather than free radical scavenging might be an important mechanism for protecting against dRib-induced oxidative damage in aβ-cell line.
- Published
- 2012
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42. Characteristics of subjects with very low serum low-density lipoprotein cholesterol and the risk for intracerebral hemorrhage
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Gwanpyo Koh, Dae Ho Lee, So Yeon Yoo, Jung Re Yu, Jae-Geun Lee, Sung Joo Koh, and Sang Ah Lee
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Male ,medicine.medical_specialty ,Time Factors ,Alcohol Drinking ,Down-Regulation ,Gastroenterology ,Risk Assessment ,Cerebral hemorrhage ,chemistry.chemical_compound ,Risk Factors ,Internal medicine ,Republic of Korea ,medicine ,Humans ,cardiovascular diseases ,Aged ,Dyslipidemias ,Retrospective Studies ,Intracerebral hemorrhage ,business.industry ,Cholesterol ,Incidence (epidemiology) ,Incidence ,Liver Diseases ,Low-density lipoprotein ,Statins ,Retrospective cohort study ,Cholesterol, LDL ,Middle Aged ,medicine.disease ,nervous system diseases ,Hypocholesterolemia ,Endocrinology ,chemistry ,Kidney Failure, Chronic ,Serum low density lipoprotein ,lipids (amino acids, peptides, and proteins) ,Female ,Original Article ,Hydroxymethylglutaryl-CoA Reductase Inhibitors ,business ,Risk assessment ,Biomarkers - Abstract
Background/Aims The clinical implications of hypocholesterolemia have not been well studied, although some studies have revealed an association between hypocholesterolemia and intracerebral hemorrhage (ICH). We evaluated the clinical characteristics of subjects with very low-density lipoprotein cholesterol (LDL-C) and compared the risk for ICH using various clinical parameters. Methods Using hospital records, we evaluated the clinical characteristics of subjects with LDL-C levels ≤ 40 mg/dL (very low LDL-C group). We also evaluated the risk for ICH in this very low LDL-C group and in subjects with low LDL-C ≤ 70 mg/dL (low LDL-C group). Results Among 34,415 subjects who presented at the laboratory for serum LDL-C measurements, 250 subjects had a very low serum LDL-C level (≤ 40 mg/dL). About half of the subjects were statin users; the very low LDL levels in the other subjects were likely attributable to alcohol consumption or a various chronic illness such as liver disease or end-stage renal disease (ESRD). ICH occurred in three subjects with very low LDL-C, all of whom had no history of statin use. ESRD tended to be associated with ICH in subjects with serum LDL-C ≤ 70 mg/dL. Conclusions About 1% of the subjects whose LDL-C was measured in the hospital had a LDL-C level ≤ 40 mg/dL, and about half of these subjects had no history of hypolipidemic therapy. ICH incidence was not related to LDL-C level or statin use.
- Published
- 2011
43. 2-Deoxy-D-ribose induces cellular damage by increasing oxidative stress and protein glycation in a pancreatic beta-cell line
- Author
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Gwanpyo Koh, Dae Ho Lee, and Jeong Taek Woo
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Glycation End Products, Advanced ,medicine.medical_specialty ,Cell Survival ,Endocrinology, Diabetes and Metabolism ,Cell ,Apoptosis ,medicine.disease_cause ,Guanidines ,Cell Line ,Protein Carbonylation ,chemistry.chemical_compound ,Endocrinology ,Glycation ,Internal medicine ,Insulin-Secreting Cells ,Ribose ,medicine ,Humans ,Annexin A5 ,Enzyme Inhibitors ,Cytotoxicity ,Glycoproteins ,Dose-Response Relationship, Drug ,Deoxyribose ,Pentetic Acid ,Flow Cytometry ,Oxidative Stress ,medicine.anatomical_structure ,chemistry ,Biochemistry ,Advanced glycation end-product ,Pyridoxamine ,Reactive Oxygen Species ,Oxidative stress - Abstract
2-Deoxy-D-ribose (dRib) is a sugar with a high reducing capacity. We previously reported that dRib induced damage in pancreatic beta-cells. The aim of this study was to investigate the mechanism of dRib-induced beta-cell damage. 2-Deoxy-D-ribose provoked cytotoxicity and apoptosis within 24 hours in HIT-T15 cells. Three antiglycating agents-diethylenetriaminepentaacetic acid, aminoguanidine, and pyridoxamine-dose dependently inhibited dRib-triggered cytotoxicity and significantly suppressed apoptosis induced by dRib. 2-Deoxy-d-ribose increased intracellular reactive oxygen species and protein carbonyl levels in a dose-dependent manner. Diethylenetriaminepentaacetic acid and aminoguanidine significantly reduced dRib-induced rises in intracellular reactive oxygen species. All 3 inhibitors decreased the production of intracellular protein carbonyls by dRib. On incubation with albumin, dRib increased dicarbonyl and advanced glycation end product formation. Aminoguanidine and pyridoxamine significantly decreased the dicarbonyl and advanced glycation end product augmentations. These results suggest that both oxidative stress and protein glycation are important mechanisms of dRib-induced damage in a pancreatic beta-cell line.
- Published
- 2009
44. PO022 APOLIPOPROTEIN B IS RELATED TO METABOLIC SYNDROME INDEPENDENTLY OF LDL-CHOLESTEROL IN PATIENTS WITH TYPE 2 DIABETES
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S.O. Chin, Y.-h. Lim, S.Y. Yoo, Gwanpyo Koh, and S.A. Lee
- Subjects
Ldl cholesterol ,medicine.medical_specialty ,Apolipoprotein B ,biology ,business.industry ,Endocrinology, Diabetes and Metabolism ,General Medicine ,Type 2 diabetes ,medicine.disease ,Endocrinology ,Internal medicine ,Diabetes mellitus ,Internal Medicine ,biology.protein ,Medicine ,In patient ,Metabolic syndrome ,business - Published
- 2014
45. Acute hyperglycemia and activation of the beta-adrenergic system do not exhibit synergistic inhibitory actions on thyrotropin-releasing hormone (TRH)-induced thyroid stimulating hormone (TSH) secretion
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Inmyung Yang, Seungjoon Oh, Sung Woo Park, Young-Seol Kim, Gwanpyo Koh, Jinwoo Kim, Cheol-Young Park, Jeong Taek Woo, Seungjoon Park, Sung-Woon Kim, Sookjin Sohn, Ki-Won Oh, and Eunhee Kim
- Subjects
Adult ,Male ,endocrine system ,medicine.medical_specialty ,endocrine system diseases ,Endocrinology, Diabetes and Metabolism ,Thyrotropin-releasing hormone ,Administration, Oral ,Thyrotropin ,Stimulation ,Inhibitory postsynaptic potential ,Endocrinology ,TRH stimulation test ,Thyroid-stimulating hormone ,Internal medicine ,Receptors, Adrenergic, beta ,medicine ,Humans ,Infusions, Intravenous ,Thyrotropin-Releasing Hormone ,Chemistry ,Isoproterenol ,Drug Synergism ,Adrenergic beta-Agonists ,Somatostatin ,Glucose ,Basal (medicine) ,Hyperglycemia ,Acute Disease ,hormones, hormone substitutes, and hormone antagonists ,Hormone - Abstract
Thyrotropin-releasing hormone (TRH)-stimulated thyroid stimulating hormone (TSH) response in normal subjects is suppressed by oral glucose administration. Pharmacologic studies indicate that this suppressive action of glucose is mediated by an increase in hypothalamic somatostatin (SRIH) tone. Since activation of the beta-adrenergic system also suppresses basal TSH secretion by enhancing SRIH release we sought to determine whether isoproterenol alters the suppression of TRH-induced TSH response induced by the stimulation of glucose. Four tests were performed in seven healthy young men: Test 1: 200 microg TRH (iv) at 0 min; Test 2: 100 g oral glucose at -30 min and TRH at 0 min; Test 3: TRH at 0 min with isoproterenol (0.012 microg/kg, iv) infused continuously; Test 4: oral glucose at -30 min, TRH at 0 min with isoproterenol infused continuously. Pretreatment with glucose significantly suppressed TRH-induced TSH secretion. Isoproterenol infusion also suppressed the TRH-induced TSH secretion, but it did not enhance the inhibitory action of glucose on TSH secretion. The degree of suppression induced by glucose was significantly higher than that achieved by isoproterenol. These data suggest that combined administration of glucose and isoproterenol does not exhibit synergistic inhibitory actions on TRH-stimulated TSH secretion, and that the glucose-TRH test could be used for the evaluation of the hypothalamic somatostatinergic activity.
- Published
- 2005
46. Elevated cAMP level attenuates 2-deoxy-d-ribose-induced oxidative damage in pancreatic beta-cells
- Author
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Seungjoon Oh, Sung-Woon Kim, Gwanpyo Koh, Suk Chon, Jinwoo Kim, Jeong Taek Woo, Young-Seol Kim, and Kwang Sik Suh
- Subjects
medicine.medical_specialty ,IBMX ,Cell Survival ,Biophysics ,Drug Resistance ,Apoptosis ,medicine.disease_cause ,Biochemistry ,Cell Line ,chemistry.chemical_compound ,Islets of Langerhans ,Internal medicine ,Cricetinae ,Ribose ,medicine ,Cyclic AMP ,Animals ,Cytotoxicity ,Molecular Biology ,chemistry.chemical_classification ,Reactive oxygen species ,Forskolin ,Dose-Response Relationship, Drug ,Deoxyribose ,Oxidative Stress ,Endocrinology ,chemistry ,Oxidation-Reduction ,Intracellular ,Oxidative stress - Abstract
Glucose toxicity to pancreatic β-cells is defined as irreversible β-cell damage, including apoptosis, caused by chronic exposure to high glucose levels in type 2 diabetes. Oxidative stress is an important mechanism for glucose toxicity to pancreatic β-cells. Reducing sugars produce reactive oxygen species through autoxidation and protein glycosylation. 2-Deoxy- d -ribose (dRib) is a reducing sugar with high reactivity. We investigated whether cAMP-stimulating agents could protect β-cells from dRib-induced oxidative damage. HIT-T15 cells were cultured with various concentrations of dRib for 24 h. We measured cell survival, intracellular cAMP and H 2 O 2 levels, and apoptosis. dRib decreased cell survival in a dose- and time-dependent manner and markedly increased intracellular H 2 O 2 levels and apoptosis. N -Acetyl- l -cysteine decreased dRib-induced rises in intracellular H 2 O 2 and apoptosis to control levels. Forskolin, IBMX, and dbcAMP markedly elevated intracellular cAMP levels and significantly attenuated dRib-induced cytotoxicity and apoptosis, but had no influence on the dRib-induced rise in intracellular H 2 O 2 levels. These results demonstrate that dRib produced oxidative stress and apoptosis in pancreatic β-cells and that elevated intracellular cAMP levels reduced dRib-induced damage, independent of reactive oxygen species metabolism.
- Published
- 2005
47. Polymorphisms in interleukin-1 beta and Interleukin-1 receptor antagonist genes are associated with kidney failure in Korean patients with type 2 diabetes mellitus
- Author
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Seung Joon Oh, Jinwoo Kim, Sung Woon Kim, Young Seol Kim, Joo-Ho Chung, Byung-Cheol Lee, Sang-Ho Lee, Jeoung-Taek Woo, Gwanpyo Koh, Tae Won Lee, Myung Jae Kim, Seong Do Kim, Hee Jae Lee, Byoung Soo Cho, Seong Dong Sohn, and Chun-Gyoo Ihm
- Subjects
Nephrology ,Male ,medicine.medical_specialty ,Genotype ,medicine.medical_treatment ,Sialoglycoproteins ,Type 2 diabetes ,Diabetic nephropathy ,Gene Frequency ,Risk Factors ,Internal medicine ,Medicine ,Humans ,Diabetic Nephropathies ,Genetic Predisposition to Disease ,Aged ,Korea ,Polymorphism, Genetic ,business.industry ,Type 2 Diabetes Mellitus ,Interleukin ,Middle Aged ,medicine.disease ,Interleukin 1 Receptor Antagonist Protein ,Endocrinology ,Cytokine ,Interleukin 1 receptor antagonist ,Diabetes Mellitus, Type 2 ,Multigene Family ,Immunology ,Female ,business ,Kidney disease ,Interleukin-1 - Abstract
Background/Aim: Cytokines play an important role in the pathogenesis of kidney diseases. The aim of the study was to investigate the impact of interleukin (IL)-1 cluster genes on diabetic nephropathy in Korean patients with type 2 diabetes mellitus (DM). Methods: We investigated –511 C/T polymorphism of IL-1β and tandem repeat polymorphism in intron 2 of IL-1 receptor antagonist in type 2 DM patients with end-stage kidney failure as compared with patients without nephropathy. Results: The IL1B2 allele was found more frequently in patients with kidney failure than in controls (57.4 vs. 46.1%, p < 0.05). An excessive homozygous carriage of IL1B2 was found in patients with kidney failure when compared with controls (30.5 vs. 18.3%, p < 0.05). The allelic frequency of IL1RN*2 was also higher in cases than in controls without nephropathy (8.4 vs. 2.8 %, p < 0.05). The carriage rate of IL1RN*2 was significantly associated with an increased risk of kidney failure (15.8 vs. 5.6%; OR 3.19, 95% CI 1.24–8.17). The risk of kidney failure was highest in those carrying both IL1RN*2 and IL1B2 (OR 3.90, 95% CI 1.34–11.40). Conclusion: IL1B2 and IL1RN*2 genotypes of the IL-1 cluster genes are associated with diabetic nephropathy in Korean patients with type 2 DM.
- Published
- 2004
48. Soybean isoflavones inhibit tumor necrosis factor-alpha-induced apoptosis and the production of interleukin-6 and prostaglandin E2 in osteoblastic cells
- Author
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Cheol-Young Park, Jeong Taek Woo, Kwang Sik Suh, Gwanpyo Koh, Young Seol Kim, Sung Woon Kim, In Kook Park, and Jinwoo Kim
- Subjects
medicine.medical_specialty ,Programmed cell death ,medicine.medical_treatment ,Genistein ,Fluorescent Antibody Technique ,Apoptosis ,Enzyme-Linked Immunosorbent Assay ,Plant Science ,Horticulture ,Biology ,Nitric Oxide ,Biochemistry ,Dinoprostone ,chemistry.chemical_compound ,Mice ,Internal medicine ,medicine ,In Situ Nick-End Labeling ,Animals ,Prostaglandin E2 ,Molecular Biology ,Immunoassay ,Osteoblasts ,Estradiol ,Interleukin-6 ,Tumor Necrosis Factor-alpha ,Daidzein ,food and beverages ,General Medicine ,3T3 Cells ,Isoflavones ,Endocrinology ,chemistry ,Tumor necrosis factor alpha ,Soybeans ,Cell Division ,Prostaglandin E ,medicine.drug ,Interleukin-1 - Abstract
The effects of individual soybean isoflavones, genistein (4',5,7-trihydroxyisoflavone) and daidzein (4',7-dihydroxyisoflavone), on tumor necrosis factor-alpha (TNF-alpha)-induced apoptosis and the production of local factors in osteoblastic cells has been investigated. Soybean isoflavones increased DNA synthesis and the number of viable cells. When cells were treated with TNF-alpha, the number of viable cells dose-dependently decreased. The decrease in cell number caused by TNF-alpha treatment was due to apoptosis, which was confirmed by TUNEL and cell death ELISA analyses. Soybean isoflavones inhibited apoptosis of osteoblastic cells subjected to TNF-alpha treatment. MC3T3-E1 osteoblastic cells secrete interleukin-6 (IL-6), interleukin-1beta (IL-1beta), nitric oxide (NO) and prostaglandin E(2) (PGE(2)) constitutively, but at low levels. Soybean isoflavones had no effect on the constitutive production of these local factors. When cells were treated with TNF-alpha (10(-10)M), the production of IL-6 and PGE(2), but not that of IL-1beta and NO, significantly increased. Treatment with soybean isoflavones (10(-5)M), in the presence of TNF-alpha (10(-10)M), for 48 h inhibited production of IL-6 and PGE(2), suggesting the antiresorptive action of soy phytoestrogen may be mediated by decreases in these local factors. The findings of this study thus suggest that soybean isoflavones may promote the function of osteoblastic cells and play an important role in bone remodeling.
- Published
- 2003
49. Letter: Association between Smoking Status and Metabolic Syndrome in Men (Korean J Obes 2014;23:99-105)
- Author
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Gwanpyo Koh
- Subjects
medicine.medical_specialty ,business.industry ,Internal medicine ,Medicine ,Smoking status ,Metabolic syndrome ,Association (psychology) ,business ,medicine.disease - Published
- 2014
50. Gut Hormone Response to Diet
- Author
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Gwanpyo Koh
- Subjects
medicine.medical_specialty ,Endocrinology ,Chemistry ,Internal medicine ,medicine ,Enteroendocrine cell ,Type 2 diabetes ,medicine.disease ,Obesity ,Hormone - Published
- 2014
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