Diabetes & Metabolism Journal

Je Ho Han (Han JH)

6 Articles

Treatment of Type 1 Diabetes through Genetically Engineered K-cell Transplantation in a Mouse Model.: Ju Yeon Sim, Ju Hee Kim, Yu Bae Ahn, Ki Ho Song, Je Ho Han, Bong Yun Cha, Sook Kyung Lee, Sung Dae Moon; Korean Diabetes J. 2009;33(6):466-474. Published online December 1, 2009; DOI: https://doi.org/10.4093/kdj.2009.33.6.466

2,137 View
21 Download

Abstract PDF: BACKGROUND
K-cells function as targets for insulin gene therapy. In a previous study, we constructed EBV-based plasmids expressing rat preproinsulin controlled by glucose-dependent insulinotropic polypeptide promoters. In the present study, we attempted to correct hyperglycemia in vivo using genetically engineered K-cells in a mouse model of type 1 diabetes. METHODS: K-cells expressing insulin were transplanted under the kidney capsules of STZ-induced diabetic mice. The blood glucose levels and body weights of the experimental animals were measured daily. After four weeks, the mice were injected intra-peritoneally with 2 g/kg glucose following a 6 hr fast. Blood glucose levels were measured immediately following glucose injections. All animals were sacrificed at the end of the glucose tolerance study, and pancreas and graft-bearing kidney tissue samples were stained with antibodies against insulin, glucagon, and C-peptide. RESULTS: The body weights of K-cell-transplanted diabetic mice increased after transplantation, whereas those of untreated diabetic control mice continued to decline. The blood glucose levels of K-cell-transplanted diabetic mice decreased gradually during the two weeks following transplantation. After intra-peritoneal injection of glucose into K-cell-transplanted diabetic mice, blood glucose levels increased at 30 minutes, and were restored to the normal range between 60 and 90 minutes, while untreated control diabetic mice continued to experience hyperglycemia. Kidney capsules containing transplanted K-cells were removed, and sections were stained with anti-insulin antibodies. We detected insulin-positive cells in the kidney capsules of K-cell-transplanted diabetic mice, but not in untreated control mice. CONCLUSION: We detected glucose-dependent insulin secretion in genetically engineered K-cells in a mouse model of type 1 diabetes. Our results suggest that genetically modified insulin producing K-cells may act as surrogate beta-cells to effectively treat type 1 diabetes.

Glucose-dependent Insulin Secretion from Genetically Engineered K-cells Using EBV-based Episomal Vector.: Ju Hee Kim, Sung Dae Moon, Seung Hyun Ko, Yu Bai Ahn, Ki Ho Song, Hyang Sook Lim, Sook Kyung Lee, Soon Jip Yoo, Hyun Shik Son, Kun Ho Yoon, Bong Yun Cha, Ho Young Son, Sung Joo Kim, Je Ho Han; Korean Diabetes J. 2007;31(1):9-21. Published online January 1, 2007; DOI: https://doi.org/10.4093/jkda.2007.31.1.9

2,590 View
18 Download
2 Crossref

BACKGROUND
Type 1 diabetes mellitus is an autoimmune disease resulting in destruction of the pancreatic beta cells. Insulin gene therapy for these patients has been vigorously researched. The strategy for achieving glucose-dependent insulin secretion in gene therapy relies on glucose-responsive transcription of insulin mRNA and the constitutive secretory pathway of target non-beta cells. We observed that genetically engineered K-cells using Epstein-Barr virus (EBV)-based episomal vector can produce glucose-regulated insulin production. METHODS: Green fluorescent protein (GFP) or rat-preproinsulin (PPI) expression cassette transcriptionally controlled by the promoter of glucose dependent insulinotropic peptide (GIPP) is fused to pCEP4 containing the origin of replication (oriP) and Epstein-Barr virus nuclear antigen 1 (EBNA-1). CMV promoter was replaced by subcloning the GIPP into pCEP4 to generate pGIPP/CEP4. Two recombinant EBV-based episomal vectors, pGIPP/GFP/CEP4 and pGIPP/PPI/CEP4, were constructed. pGIPP/GFP/CEP4 and pGIPP/PPI/CEP4 containing K-cell specific GIPP were co-transfected into STC-1. K-cell was isolated from the clonal expansion of the fluorescent cells selected by hygromycin treatment in STC-1, and were analyzed for the expression of glucokinase (GK) or transcription factors involved in pancreas development. K-cells concurrently transfected with pGIPP/PPI/CEP4 and pGIPP/GFP/CEP4 were analyzed for the transcripts of PPI by RT-PCR, and for the glucose dependent insulin expression by immunocytochemistry or insulin assay using ultra-sensitive rat-specific insulin ELISA kit. RESULT: STC-1 was stably-transfected with pGIPP/GFP/CEP4 along with pGIPP/PPI/CEP4. Genetically selected fluorescent K-cells expressed GK and transcription factors involved in pancreas development. And K-cells transfected with pGIPP/PPI/CEP4 contained detectable levels of PPI transcripts and showed glucose-dependent immunoreactive insulin secretion. CONCLUSION: We identified genetically engineered K-cells which exert a glucose-dependent insulin expression using EBV-based episomal vector. The similarities between K-cells and pancreatic beta cells support that K-cells may make effective and ideal targeting cells for insulin gene therapy or alternative cell therapy.

Citations

Citations to this article as recorded by

Relationship of traditional and nontraditional cardiovascular risk factors to coronary artery calcium in type 2 diabetes
Ju-Yeon Sim, Ju-Hee Kim, Yu-Bae Ahn, Ki-Ho Song, Je-Ho Han, Bong-Yun Cha, Sook-Kyung Lee, Sung-Dae Moon
Korean Diabetes Journal.2009; 33(6): 466. CrossRef
Transdifferentiation of Enteroendocrine K-cells into Insulin-expressing Cells
Esder Lee, Jun Mo Yu, Min Kyung Lee, Gyeong Ryul Ryu, Seung-Hyun Ko, Yu-Bae Ahn, Sung-Dae Moon, Ki-Ho Song
Korean Diabetes Journal.2009; 33(6): 475. CrossRef

In Vitro Expansion and Differentiation of Islet Precursor Cells from Cultured Neonatal Porcine Pancreatic Tissue.: Yu Bae Ahn, Kun Ho Yoon, Sun Hee Seo, Seung Hyun Ko, Ki Ho Song, Je Ho Han, Soon Jip Yoo, Hyun Sik Son, Moo Il Kang, Bong Yun Cha, Kwang Woo Lee, Ho Young Son, Sung Koo Kang; Korean Diabetes J. 2000;24(3):310-322. Published online January 1, 2001

1,014 View
17 Download

Abstract PDF: BACKGROUND
Neonatal porcine pancreas is an attractive alternative source for islet transplantation because of its growth potential and availability. Porcine neonatal pancreatic cell clusters (NPCCs) consist mainly of protodifferentiated cells expressing both the duct cell marker pancytokeratin and islet hormones. In this study, we investigated to expand and mature the pancreas duct cells contained in porcine NPCCs with extracellular matrix. METHODS: For NPCCs, pancreas obtained from neonatal pigs were minced, digested with collagenase and cultured overnight. Then NPCCs were further dispersed to small cell groups and cultured on HTB-9 extracellular matrix: the tissue attached and formed monolayer patches. At the 3rd and 8th days, tissue was fixed, immunostained for pancytokeratin (panCK), vimentin (VT) and islet hormones. RESULTS: During 5 days culture, the total cell numbers increased 3.2 fold on the matrix, and 1.6 fold on the sticky dish, respectively. Insulin positive cells (Ins+) were 6.0% of total cells at day 3 and increased 1.6 fold in numbers at day 8. There was significant increase in DNA content of NPCCs in monolayers on both sticky dishes and HTB-9 matrix. In contrast, insulin content of both groups decreased during culture periods. Until 8 days of culture after dispersion of porcine NPCC, most duct cells costained with panCK and VT. CONCLUSION: We observed NPCCs were composed of many of duct cells which were known to be endocrine precursor cells and monolayer culture of NPCC withextracellular matrix resulted in the proliferation and differentiation of pancreatic duct cells.

Effect of Oxidezed LDL in Insulin Binding, Internalization and Recycling of Insulin Receptor in Cultured Bovine Aortic Endothelial Cells.: Sung Dae Moon, Bong Yun Cha, Hye Soo Kim, Sang Ah Jang, Yu Bae An, Ki Ho Song, Je Ho Han, Soon Jib You, Kun Ho Yoon, Moo Il Kang, Kwang Woo Lee, Ho Young Son, Sung Koo Kang; Korean Diabetes J. 1999;23(3):243-255. Published online January 1, 2001

1,042 View
17 Download

Abstract PDF: BACKGROUND
Endothelial dysfunction is perhaps one of the earliest manifestations of atherosclerosis. This abnormality is in part due to altered membrane signal transduction in endothelial cells. Oxidized LDL that is atherogenic may induce endothelial dysfunction, and its presence has been documented in atherosclerotic vessels. Many studies have shown that oxidized LDL inhibits signaling pathways mediated by inhibitory GTP-binding proteins (Gi- protein). It is also known that G-protein is involved in insulin recycling on cultured human umbilical vein endothelial cells. Therefore, to determine the effect of oxidized LDL on endothelial cells: insulin binding, internalization, and the recycling of insulin receptors were assessed in cultured bovine aortic endothelial cells treated with native LDL, oxidized LDL, and in some cells pretreated with pertussis toxin before the incubation with oxidized LDL. METHOD: Native LDL (density 1.019 1.063 g/mL) was obtained from using the rapid single discontinuous density gradient ultracentrifugation of plasma samples from a single donor. Oxidized LDL was prepared by exposing samples of native LDL to CuSO4 (5 uM) at 37't for 24 hours. Endothelial cells at 80% confluence were treated with the indicated concentrations of native LDL, oxidized LDL, and some cells were pretreated with pertussis toxin for 6 hrs before the incubation with oxidized LDL. These cells were incubated for 24 72 hours. RESULTS: 1. Binding of (125)I-insulin(0.17nM) to endothelial cells treated with increasing concentrations of oxidized LDL shows dose-dependent decrease. There were significant differences in insulin binding between native LDL and oxidized LDL-treated cells (p<0.05). Binding of 'I-insulin (0.17 nM) to endothelial cells treated with increasing culture time of oxidized LDL shows more decreased than that of native LDL significantly (p<0.05). And oxidized LDL had additive effect, but not significant, with pertussis toxin on the specific (125)I-insulin binding to bovine aortic endothelial cells. 2. Internalization of insulin receptors reached rapidly to its maximal level around 30min at 37'C. At 60 min, oxidized-LDL treated cells was less increased in internalization of insulin receptors than that of native LDL treated cells [59.1+1.9% of total cell associated insulin (mean+SE) vs. 67.5+1.1%, p<0.05]. There were additive effects, but not significant differences, between oxidized LDL and pretreated with pertussis toxin before the incubation with oxidized LDL. 3. After 30 min of incubation with unlabeled insulin (33 nM), insulin binding in oxidized LDL treated cells was significantly higher compared to native LDL treated cells (69.0+2.5% of control values vs. 63.7+1.2%, p<0.05), suggesting that oxidized-LDL decreased internalization of insulin receptors. And during the process of recycling, there were significant differences in insulin receptor recycling between the oxidized LDL and native LDL treated cells, but oxidized LDL had an additive effect, but not significant, with pertussis toxin on insulin receptor recycling to the bovine aortic endothelial cells. CONCLUSION: 1. The findings in this study suggest that oxidized LDL may play a causative role to produce the insulin resistance by inhibiting insulin binding, internalization and recycling of insulin receptor in cultured bovine aortic endothelial cells 2. This study suggests that the effect of oxidized LDL to the bovine aortic endothelial cells in insulin binding and receptor-mediated transcytosis is caused by inhibiting pertussis toxin sensitive Gi-protein.

Effect of Hyperglycemia on Internalization of Insulin-receptor Complexes in Human Umbilical Vein Endothelial Cells.: Ki Ho Song, Yu Bae Ahn, Je Ho Han, Soon Jip Yoo, Kun Ho Yoon, Moo Il Kang, Bong Yun Cha, Kwang Woo Lee, Ho Young Son, Sung Koo Kang; Korean Diabetes J. 1999;23(2):131-141. Published online January 1, 2001

1,130 View
21 Download

Abstract PDF: BACKGROUND
It is well known that hyperglycemia activates protein kinase C (PKC) in vascular endothelial cells. However, the effect of hyperglycemia on internalization and recycling of insulin receptors by insulin in endothelial cells has not been examined thus far. METHODS: Human umbilical vein endothelial cells (HUVECs) were isolated from healthy, pregnant women. Confluent HUVECs were incubated in a culture media containing either 5 (NG group) or 25 mM glucose (HG group) for 4 days. Then, we measured the insulin binding, internalization and recycling of the insulin receptor and release of internalized insulin into the media. RESULTS: There was no difference in binding of 0.17 nM 125I-insulin between the two groups. However, the amount of internalized 125I-insulin, determined by the aeid washing method, was significantly greater in the HG group compared to the NG group. The addition of 10 pM 1-(5-isoquino-linesulfonyl)-2-methyl-piperazine (H7), a PKC inhibitor, to the HG group prevented the increase of internalization in 125I-insulin. In addition, preincubation with unlabeled insulin resulted in a decrease of 125I-insulin binding to a greater extent in the HG group compared with the NG group, indicating that high glucose levels increased internalizntion of insulin receptors. The high glucose-induced increase in internalization of insulin receptors was prevented by an addition of H7. Recycling of insulin receptors to the cell surface was not affected by high glucose. Internalized 125I-insulin released into media with time. The released amount of I-insulin in the HC group tended to be greater compared to the NG group. CONCLUSION: These results suggest that hyperglycemia may increase internalization of the insulin-receptor complexes in vascular endothelial cells through PKC activation.

Prevalence of micro and macroalbuminuria in relation to hypertension and chronic diabetic vascular complications among type II diabeticpatients.: Hyuk Ho Kwon, Je Ho Han, Jong Min Lee, Soon Jip Yoo, Hyun Sik Son, Kun Ho Yoon, Moo Il Kang, Jwan Soo Hong, Bong Yun Cha, Kwang Woo Lee, Ho Young Son, Sung Ku Kang; Korean Diabetes J. 1992;16(4):317-324. Published online January 1, 2001

1,006 View
16 Download

Abstract PDF: No abstract available.

Author index