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Chittepu VCSR, Kalhotra P, Gallardo-Velázquez T, Robles-de la Torre RR, Osorio-Revilla G. Designed Functional Dispersion for Insulin Protection from Pepsin Degradation and Skeletal Muscle Cell Proliferation: In Silico and In Vitro Study. NANOMATERIALS (BASEL, SWITZERLAND) 2018; 8:E852. [PMID: 30347680 PMCID: PMC6215209 DOI: 10.3390/nano8100852] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 10/12/2018] [Accepted: 10/17/2018] [Indexed: 12/25/2022]
Abstract
Functionalized single-walled carbon nanotubes with polyethylene glycol (PEGylated SWCNTs) are a promising nanomaterial that recently has emerged as the most attractive "cargo" to deliver chemicals, peptides, DNA and RNAs into cells. Insulin therapy is a recommended therapy to treat diabetes mellitus despite its side effects. Recently, functional dispersion made up of bioactive peptides, bioactive compounds and functionalized carbon nanomaterials such as PEGylated SWCNTs have proved to possess promising applications in nanomedicine. In the present study, molecular modeling simulations are utilized to assist in designing insulin hormone-PEGylated SWCNT composites, also called functional dispersion; to achieve this experimentally, an ultrasonication tool was utilized. Enzymatic degradation assay revealed that the designed functional dispersion protects about 70% of free insulin from pepsin. In addition, sulforhodamine B (SRB) assay, the quantification of insulin and glucose levels in differentiated skeletal muscle cell supernatants, reveals that functional dispersion regulates glucose and insulin levels to promote skeletal muscle cell proliferation. These findings offer new perspectives for designed functional dispersion, as potential pharmaceutical preparations to improve insulin therapy and promote skeletal muscle cell health.
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Affiliation(s)
- Veera C S R Chittepu
- Departamento de Ingeniería Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Av. Wilfrido Massieu S/N, Col. Unidad Profesional Adolfo López Mateos, Zacatenco, CP. Ciudad de Mexico 07738, Mexico.
| | - Poonam Kalhotra
- Departamento de Biofísica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional. Prolongación de Carpio y Plan de Ayala S/N, Col. Santo Tomás, CP. Ciudad de Mexico 11340, Mexico.
| | - Tzayhri Gallardo-Velázquez
- Departamento de Biofísica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional. Prolongación de Carpio y Plan de Ayala S/N, Col. Santo Tomás, CP. Ciudad de Mexico 11340, Mexico.
| | - Raúl René Robles-de la Torre
- Centro de Investigación en Biotecnología Aplicada CIBA, Instituto Politécnico Nacional, Carretera Estatal, Tecuexcomac-Tepetitla, Km 1.5, CP. Tlaxcala 90700, Mexico.
| | - Guillermo Osorio-Revilla
- Departamento de Ingeniería Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Av. Wilfrido Massieu S/N, Col. Unidad Profesional Adolfo López Mateos, Zacatenco, CP. Ciudad de Mexico 07738, Mexico.
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Corbin KD, Driscoll KA, Pratley RE, Smith SR, Maahs DM, Mayer-Davis EJ. Obesity in Type 1 Diabetes: Pathophysiology, Clinical Impact, and Mechanisms. Endocr Rev 2018; 39:629-663. [PMID: 30060120 DOI: 10.1210/er.2017-00191] [Citation(s) in RCA: 120] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Accepted: 06/21/2018] [Indexed: 02/07/2023]
Abstract
There has been an alarming increase in the prevalence of obesity in people with type 1 diabetes in recent years. Although obesity has long been recognized as a major risk factor for the development of type 2 diabetes and a catalyst for complications, much less is known about the role of obesity in the initiation and pathogenesis of type 1 diabetes. Emerging evidence suggests that obesity contributes to insulin resistance, dyslipidemia, and cardiometabolic complications in type 1 diabetes. Unique therapeutic strategies may be required to address these comorbidities within the context of intensive insulin therapy, which promotes weight gain. There is an urgent need for clinical guidelines for the prevention and management of obesity in type 1 diabetes. The development of these recommendations will require a transdisciplinary research strategy addressing metabolism, molecular mechanisms, lifestyle, neuropsychology, and novel therapeutics. In this review, the prevalence, clinical impact, energy balance physiology, and potential mechanisms of obesity in type 1 diabetes are described, with a special focus on the substantial gaps in knowledge in this field. Our goal is to provide a framework for the evidence base needed to develop type 1 diabetes-specific weight management recommendations that account for the competing outcomes of glycemic control and weight management.
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Affiliation(s)
- Karen D Corbin
- Translational Research Institute for Metabolism and Diabetes, Florida Hospital, Orlando, Florida
| | - Kimberly A Driscoll
- Department of Pediatrics, School of Medicine, University of Colorado Denver, Aurora, Colorado.,Barbara Davis Center for Diabetes, Aurora, Colorado
| | - Richard E Pratley
- Translational Research Institute for Metabolism and Diabetes, Florida Hospital, Orlando, Florida
| | - Steven R Smith
- Translational Research Institute for Metabolism and Diabetes, Florida Hospital, Orlando, Florida
| | - David M Maahs
- Division of Pediatric Endocrinology, Department of Pediatrics, Stanford University, Stanford, California
| | - Elizabeth J Mayer-Davis
- Department of Nutrition, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.,Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
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Gillespie AL, Pan X, Marco-Ramell A, Meharg C, Green BD. Detailed characterisation of STC-1 cells and the pGIP/Neo sub-clone suggests the incretin hormones are translationally regulated. Peptides 2017; 96:20-30. [PMID: 28870797 DOI: 10.1016/j.peptides.2017.08.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 07/10/2017] [Accepted: 08/28/2017] [Indexed: 12/25/2022]
Abstract
STC-1 is a heterogeneous plurihormonal cell line producing several prominent gut peptide hormones. pGIP/Neo is a genetically selected sub-clone of STC-1 with augmented levels of glucose-dependent insulinotropic peptide (GIP). Morphometric parameters, hormone concentrations, mRNA transcripts, hormone immunocytochemistry and nutrient utilisation/production of these two cell lines were compared. Proglucagon-derived peptides (Glucagon-like peptide-1 (GLP-1) and - 2(GLP-2)) were lower in sub-clone cells than progenitor cells. High Content Analysis found altered intracellular GLP-1, GIP, cholecystokinin (CCK) and peptide YY (PYY) levels and differing hormone co-localisation. The proportion pGIP/Neo cells containing GIP immunoreactivity (82%) was greater than STC-1 (65%), as were the proportion with 'GIP only', 'GLP-1+GIP' or 'GIP+PYY' immunoreactivity. Most surprisingly mRNA transcripts of the proglucagon and GIP genes were inversely correlated to the levels of their translated peptides. This strongly suggests that proglucagon and GIP are encoded on 'translationally regulated genes' - a characteristic possessed by other endocrine hormones. Metabolomic profiling revealed differences in cellular nutrient utilisation/production and that under normal culture conditions both cell lines exhibit signs of overflow metabolism. These studies provide an insight into the metabolism and properties of these valuable cells, suggesting for the first time that incretin hormone genes are translationally regulated.
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Affiliation(s)
- Anna L Gillespie
- Institute for Global Food Security (IGFS), Queen's University Belfast, United Kingdom
| | - Xiaobei Pan
- Institute for Global Food Security (IGFS), Queen's University Belfast, United Kingdom
| | - Anna Marco-Ramell
- Biomarkers and Nutrimetabolomics Group, University of Barcelona, Spain
| | - Caroline Meharg
- Institute for Global Food Security (IGFS), Queen's University Belfast, United Kingdom
| | - Brian D Green
- Institute for Global Food Security (IGFS), Queen's University Belfast, United Kingdom.
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Gautam P, Recino A, Foale RD, Zhao J, Gan SU, Wallberg M, Calne R, Lever AML. Promoter optimisation of lentiviral vectors for efficient insulin gene expression in canine mesenchymal stromal cells: potential surrogate beta cells. J Gene Med 2016; 18:312-321. [PMID: 27572655 DOI: 10.1002/jgm.2900] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 08/02/2016] [Accepted: 08/25/2016] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND The lack of an ideal cell type that can be easily acquired, modified to produce insulin, and re-implanted has been a limitation for ex vivo insulin gene therapy. Canine diabetes is currently treated with human insulin and is a good model for human diabetes. Mesenchymal stromal cells (MSCs) are a promising candidate cell type for gene therapy. In the present study, we optimised insulin production using lentiviral transduced canine MSCs (cMSCs), aiming to evaluate their ability for use as surrogate beta cells. METHODS Canine MSCs were derived from bone marrow and validated by measuring the expression of MSC lineage specific markers. Lentivirus vectors encoding the proinsulin gene (with or without a Kozak sequence) under the control of spleen focus forming virus, cytomegalovirus, elongation factor 1α and simian virus 40 promotors were generated and used to transduce primary cMSCs and a hepatocyte cell line. The insulin-producing capacity of transduced primary cMSCs was assessed by measuring the concentration of C-peptide produced. RESULTS Primary cMSC could be readily expanded in culture and efficiently transduced using lentiviral vectors encoding proinsulin. Increasing the multiplicity of infection from 3 to 20 led to an increase in C-peptide secretion (from 1700 to 4000 pmol/l). The spleen focus forming virus promoter conferred the strongest transcriptional ability. CONCLUSIONS The results of the present study suggest that optimised lentiviral transduction of the insulin gene into primary cMSCs renders these cells capable of secreting insulin over both the short- and long-term, in sufficient quantities in vitro to support their potential use in insulin gene therapy.
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Affiliation(s)
- Pratigya Gautam
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - Asha Recino
- Department of Pathology, University of Cambridge, Cambridge, UK
| | - Robert D Foale
- Dick White Referrals, Station Farm, Six Mile Bottom, Suffolk, UK
| | - Jing Zhao
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - Shu Uin Gan
- Department of Surgery, National Institute of Singapore, Singapore
| | - Maja Wallberg
- Dick White Referrals, Station Farm, Six Mile Bottom, Suffolk, UK
| | - Roy Calne
- Department of Surgery, University of Cambridge, Cambridge, UK
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Miranda-Perez ME, Ortega-Camarillo C, Del Carmen Escobar-Villanueva M, Blancas-Flores G, Alarcon-Aguilar FJ. Cucurbita ficifolia Bouché increases insulin secretion in RINm5F cells through an influx of Ca(2+) from the endoplasmic reticulum. JOURNAL OF ETHNOPHARMACOLOGY 2016; 188:159-166. [PMID: 27174079 DOI: 10.1016/j.jep.2016.04.061] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 04/15/2016] [Accepted: 04/28/2016] [Indexed: 06/05/2023]
Abstract
ETHNOPHARMACOLOGICAL IMPORTANCE Cucurbita ficifolia Bouché(C. ficifolia) is a plant used in Mexican traditional medicine to control type 2 diabetes (T2D). The hypoglycemic effect of the fruit of C. ficifolia has been demonstrated in different experimental models and in T2D patients. It has been proposed that D-chiro-inositol (DCI) is the active compound of the fruit. Additionally, it has been reported that C. ficifolia increases the mRNA expression of insulin and Kir 6.2 (a component of the ATP-sensitive potassium (K(+)ATP) channel, which is activated by sulphonylurea) in RINm5F cells. However, it remains unclear whether C. ficifolia and DCI causes the secretion of insulin by increasing the concentration of intracellular calcium ([Ca(2+)]i) through K(+)ATP channel blockage or from the reservoir in the endoplasmic reticulum (ER). MATERIAL AND METHODS The aqueous extract of C. ficifolia was obtained and standardized with regard to its DCI content. RINm5F pancreatic β-cells were incubated with different concentrations (50, 100, 200 and 400μM) of DCI alone or C. ficifolia (9, 18, 36 and 72µg of extract/mL), and the [Ca(2+)]i of the cells was quantified. The cells were preloaded with the Ca(2+) fluorescent dye fluo4-acetoxymethyl ester (AM) and visualized by confocal microscopy. Insulin secretion was measured by an ELISA method. Subsequently, the effect of C. ficifolia on the K(+)ATP channel was evaluated. In this case, the blocker activator diazoxide was used to inhibit the C. ficifolia-induced calcium influx. In addition, the inositol 1,4,5-trisphosphate (IP3)-receptor-selective inhibitor 2-amino-thoxydiphenylborate (2-APB) was used to inhibit the influx of calcium from the ER that was induced by C. ficifolia. RESULTS It was found that DCI alone did not increase [Ca(2+)]i or insulin secretion. In contrast, treatment with C. ficifolia increased [Ca(2+)]i 10-fold compared with the control group. Insulin secretion increased by 46.9%. In the presence of diazoxide, C. ficifolia decreased [Ca(2+)]i by 50%, while insulin secretion increased by 36.4%. In contrast, in the presence of 2-APB, C. ficifolia increased [Ca(2+)]i 18-fold, while insulin secretion remained constant, indicating an additive effect. Therefore, C. ficifolia was not found to block the K(+)ATP channel. However, it did exert an effect by increasing [Ca(2+)]i from the ER, which may partly explain the insulin secretion observed following treatment with C. ficifolia. CONCLUSIONS The hypoglycemic properties of C. ficifolia can be explained in part by its effect as a secretagogue for insulin through an increase in [Ca(2+)]i from the calcium reservoir in the ER. Therefore, the mechanism of action of C. ficifolia is different to those of the currently used hypoglycemic drugs, such as sulfonylureas. These results support that C. ficifolia may be a potential natural resource for new agents to control T2D.
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Affiliation(s)
- Maria Elizabeth Miranda-Perez
- Division de Ciencia Biologicas y de la Salud (DCBS), Universidad Autonoma Metropolitana Unidad Iztapalapa (UAM-I), Avenida San Rafael Atlixco 186, Ciudad de Mexico, Mexico.
| | - Clara Ortega-Camarillo
- Unidad de Investigacion Medica en Bioquimica, HE, Centro Medico Nacional Siglo XXI. IMSS, Av. Cuauhtemoc 330, Col. Doctores, Del. Cuauhtemoc, Ciudad de Mexico, Mexico.
| | | | - Gerardo Blancas-Flores
- Laboratorio de Farmacología, Departamento de Ciencias de la Salud, DCBS, UAM-I, Avenida San Rafael Atlixco 186, Ciudad de Mexico, Mexico.
| | - Francisco Javier Alarcon-Aguilar
- Laboratorio de Farmacología, Departamento de Ciencias de la Salud, DCBS, UAM-I, Avenida San Rafael Atlixco 186, Ciudad de Mexico, Mexico.
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Mojibian M, Glavas MM, Kieffer TJ. Engineering the gut for insulin replacement to treat diabetes. J Diabetes Investig 2016; 7 Suppl 1:87-93. [PMID: 27186362 PMCID: PMC4854511 DOI: 10.1111/jdi.12479] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Accepted: 01/06/2016] [Indexed: 12/11/2022] Open
Abstract
The gut epithelium's large surface area, its direct exposure to ingested nutrients, its vast stem cell population and its immunotolerogenic environment make it an excellent candidate for therapeutic cells to treat diabetes. Thus, several attempts have been made to coax immature gut cells to differentiate into insulin-producing cells by altering the expression patterns of specific transcription factors. Furthermore, because of similarities in enteroendocrine and pancreatic endocrine cell differentiation pathways, other approaches have used genetically engineered enteroendocrine cells to produce insulin in addition to their endogenous secreted hormones. Several studies support the utility of both of these approaches for the treatment of diabetes. Converting a patient's own gut cells into meal-regulated insulin factories in a safe and immunotolerogenic environment is an attractive approach to treat and potentially cure diabetes. Here, we review work on these approaches and indicate where we feel further advancements are required.
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Affiliation(s)
- Majid Mojibian
- Laboratory of Molecular and Cellular Medicine Department of Cellular and Physiological Sciences Life Sciences Institute University of British Columbia Vancouver British Columbia Canada
| | - Maria M Glavas
- Laboratory of Molecular and Cellular Medicine Department of Cellular and Physiological Sciences Life Sciences Institute University of British Columbia Vancouver British Columbia Canada
| | - Timothy J Kieffer
- Laboratory of Molecular and Cellular Medicine Department of Cellular and Physiological Sciences Life Sciences Institute University of British Columbia Vancouver British Columbia Canada
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Abstract
BACKGROUND Cell-based insulin therapies can potentially improve glycemic regulation in insulin-dependent diabetic patients. Enteroendocrine cells engineered to secrete recombinant insulin have exhibited glycemic efficacy, but have been primarily studied as uncontrollable growth systems in immune incompetent mice. Furthermore, reports suggest that suboptimal insulin secretion remains a barrier to expanded application. METHODS Genetic and tissue engineering strategies were applied to improve recombinant insulin secretion from intestinal L-cells on both a per-cell and per-graft basis. Transduction of insulin-expressing GLUTag L-cells with lentivirus carrying an additional human insulin gene-enhanced secretion twofold. We infected cells with lentivirus expressing a luciferase reporter gene to track cell survival in vivo. To provide a growth-controlled and immune protective environment without affecting secretory capacity, cells were microencapsulated in barium alginate. Approximately 9×10(7) microencapsulated cells were injected intraperitoneally in immune competent streptozotocin-induced diabetic mice for therapeutic efficacy evaluation. RESULTS Graft insulin secretion was increased to 16 to 24 mU insulin per day. Transient normoglycemia was achieved in treated mice two days after transplantation, and endogenous insulin was sufficient to sustain body weights of treated mice receiving minimal supplementation. CONCLUSION Glycemic efficacy of a bioartificial pancreas based on insulin-secreting enteroendocrine cells is insufficient as a standalone therapy, despite enhancement of graft insulin secretion capacity. Supplemental strategies to alleviate secretion limitations should be pursued.
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Lee E, Ryu GR, Moon SD, Ko SH, Ahn YB, Song KH. Reprogramming of enteroendocrine K cells to pancreatic β-cells through the combined expression of Nkx6.1 and Neurogenin3, and reaggregation in suspension culture. Biochem Biophys Res Commun 2013; 443:1021-7. [PMID: 24365150 DOI: 10.1016/j.bbrc.2013.12.093] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Accepted: 12/17/2013] [Indexed: 10/25/2022]
Abstract
Recent studies have demonstrated that adult cells such as pancreatic exocrine cells can be converted to pancreatic β-cells in a process called cell reprogramming. Enteroendocrine cells and β-cells share similar pathways of differentiation during embryonic development. Notably, enteroendocrine K cells express many of the key proteins found in β-cells. Thus, K cells could be reprogrammed to β-cells under certain conditions. However, there is no clear evidence on whether these cells convert to β-cells. K cells were selected from STC-1 cells, an enteroendocrine cell line expressing multiple hormones. K cells were found to express many genes of transcription factors crucial for islet development and differentiation except for Nkx6.1 and Neurogenin3. A K cell clone stably expressing Nkx6.1 (Nkx6.1(+)-K cells) was established. Induction of Neurogenin3 expression in Nkx6.1(+)-K cells, by either treatment with a γ-secretase inhibitor or infection with a recombinant adenovirus expressing Neurogenin3, led to a significant increase in Insulin1 mRNA expression. After infection with the adenovirus expressing Neurogenin3 and reaggregation in suspension culture, about 50% of Nkx6.1(+)-K cells expressed insulin as determined by immunostaining. The intracellular insulin content was increased markedly. Electron microscopy revealed the presence of insulin granules. However, glucose-stimulated insulin secretion was defective, and there was no glucose lowering effect after transplantation of these cells in diabetic mice. In conclusion, we demonstrated that K cells could be reprogrammed partially to β-cells through the combined expression of Nkx6.1 and Neurogenin3, and reaggregation in suspension culture.
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Affiliation(s)
- Esder Lee
- Division of Endocrinology & Metabolism, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Gyeong Ryul Ryu
- Division of Endocrinology & Metabolism, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Sung-Dae Moon
- Division of Endocrinology & Metabolism, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Seung-Hyun Ko
- Division of Endocrinology & Metabolism, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Yu-Bae Ahn
- Division of Endocrinology & Metabolism, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Ki-Ho Song
- Division of Endocrinology & Metabolism, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
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Han J, Kim EH, Choi W, Jun HS. Glucose-responsive artificial promoter-mediated insulin gene transfer improves glucose control in diabetic mice. World J Gastroenterol 2012; 18:6420-6426. [PMID: 23197887 PMCID: PMC3508636 DOI: 10.3748/wjg.v18.i44.6420] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the effect of insulin gene therapy using a glucose-responsive synthetic promoter in type 2 diabetic obese mice.
METHODS: We employed a recently developed novel insulin gene therapy strategy using a synthetic promoter that regulates insulin gene expression in the liver in response to blood glucose level changes. We intravenously administered a recombinant adenovirus expressing furin-cleavable rat insulin under the control of the synthetic promoter (rAd-SP-rINSfur) into diabetic Leprdb/db mice. A recombinant adenovirus expressing β-galactosidase under the cytomegalovirus promoter was used as a control (rAd-CMV-βgal). Blood glucose levels and body weights were monitored for 50 d. Glucose and insulin tolerance tests were performed. Immunohistochemical staining was performed to investigate islet morphology and insulin content.
RESULTS: Administration of rAd-SP-rINSfur lowered blood glucose levels and normoglycemia was maintained for 50 d, whereas the rAd-CMV-βgal control virus-injected mice remained hyperglycemic. Glucose tolerance tests showed that rAd-SP-rINSfur-treated mice cleared exogenous glucose from the blood more efficiently than control virus-injected mice at 4 wk [area under the curve (AUC): 21 508.80 ± 2248.18 vs 62 640.00 ± 5014.28, P < 0.01] and at 6 wk (AUC: 29 956.60 ± 1757.33 vs 60 016.60 ± 3794.47, P < 0.01). In addition, insulin sensitivity was also significantly improved in mice treated with rAd-SP-rINSfur compared with rAd-CMV-βgal-treated mice (AUC: 9150.17 ± 1007.78 vs 11 994.20 ± 474.40, P < 0.05). The islets from rAd-SP-rINSfur-injected mice appeared to be smaller and to contain a higher concentration of insulin than those from rAd-CMV-βgal-injected mice.
CONCLUSION: Based on these results, we suggest that insulin gene therapy might be one therapeutic option for remission of type 2 diabetes.
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Ahmad Z, Rasouli M, Azman AZF, Omar AR. Evaluation of insulin expression and secretion in genetically engineered gut K and L-cells. BMC Biotechnol 2012; 12:64. [PMID: 22989329 PMCID: PMC3469342 DOI: 10.1186/1472-6750-12-64] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Accepted: 09/17/2012] [Indexed: 12/25/2022] Open
Abstract
Background Gene therapy could provide an effective treatment of diabetes. Previous studies have investigated the potential for several cell and tissue types to produce mature and active insulin. Gut K and L-cells could be potential candidate hosts for gene therapy because of their special features. Results In this study, we isolated gut K and L-cells to compare the potential of both cell types to produce insulin when exposed to similar conditions. The isolated pure K and L-cells were transfected with recombinant plasmids encoding insulin and with specific promoters for K or L-cells. Insulin expression was studied in response to glucose or meat hydrolysate. We found that glucose and meat hydrolysate efficiently induced insulin secretion from K and L-cells. However, the effects of meat hydrolysate on insulin secretion were more potent in both cells compared with glucose. Results of enzyme-linked immunosorbent assays showed that L-cells secreted more insulin compared with K-cells regardless of the stimulator, although this difference was not statistically significant. Conclusion The responses of K and L-cells to stimulation with glucose or meat hydrolysate were generally comparable. Therefore, both K and L-cells show similar potential to be used as surrogate cells for insulin gene expression in vitro. The potential use of these cells for diabetic gene therapy warrants further investigation.
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Affiliation(s)
- Zalinah Ahmad
- Laboratory of Vaccines and Immunotherapeutics, Institute of Bioscience, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia.
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Dave SD, Vanikar AV, Trivedi HL. Ex vivo generation of glucose sensitive insulin secreting mesenchymal stem cells derived from human adipose tissue. Indian J Endocrinol Metab 2012; 16 Suppl 1:S65-S69. [PMID: 22701849 PMCID: PMC3354929 DOI: 10.4103/2230-8210.94264] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Diabetics are incapable of producing insulin/have autoimmune mechanisms making it ineffective to control glucose secretion. We present a prospective study of glucose-sensitive insulin-secreting mesenchymal stem cells (IS-MSC) generated from human adipose tissue (h-AD) sans xenogenic material. MATERIALS AND METHODS Ten grams h-AD from donor anterior abdominal wall was collected in proliferation medium composed of α-Minimum Essential Media (α-MEM), albumin, fibroblast-growth factor and antibiotics, minced, incubated in collagenase-I at 37°C with shaker and centrifuged. Supernatant and pellets were separately cultured in proliferation medium on cell+ plates at 37°C with 5% CO(2) for 10 days. Cells were harvested by trypsinization, checked for viability, sterility, counts, flow-cytometry (CD45(-)/90(+)/73(+)), and differentiated into insulin-expressing cells using medium composed of DMEM, gene expressing up-regulators and antibiotics for 3 days. They were studied for transcriptional factors Pax-6, Isl-1, pdx-1 (immunofluorescence). C-peptide and insulin were measured by chemiluminescence. In vitro glucose sensitivity assay was carried out by measuring levels of insulin and C-peptide secretion in absence of glucose followed by 2 hours incubation after glucose addition. RESULTS Mean IS-AD-MSC quantum was 3.21 ml, cell count, 1.5 ×10(3) cells/μl), CD45(-)/90(+)/73(+) cells were 44.37% /25.52%. All of them showed presence of pax-6, pdx-1, and Isl-1. Mean C-Peptide and insulin levels were 0.36 ng/ml and 234 μU/ml, respectively, pre-glucose and 0.87 ng/ml and 618.3 μU/ml post-glucose additions. The mean rise in secretion levels was 2.42 and 2.65 fold, respectively. CONCLUSION Insulin-secreting h-AD-MSC can be generated safely and effectively showing in vitro glucose responsive alteration in insulin and C-peptide secretion levels.
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Affiliation(s)
- Shruti D. Dave
- Department of Pathology, Laboratory Medicine, Transfusion Services and Immunohematology, G. R. Doshi and K. M. Mehta Institute of Kidney Diseases and Research Centre, Dr. H.L. Trivedi Institute of Transplantation Sciences, Civil Hospital Campus, Asarwa, Ahmedabad, Gujarat, India
| | - Aruna V. Vanikar
- Department of Pathology, Laboratory Medicine, Transfusion Services and Immunohematology, G. R. Doshi and K. M. Mehta Institute of Kidney Diseases and Research Centre, Dr. H.L. Trivedi Institute of Transplantation Sciences, Civil Hospital Campus, Asarwa, Ahmedabad, Gujarat, India
| | - Hargovind L Trivedi
- Department of Nephrology, G. R. Doshi and K. M. Mehta Institute of Kidney Diseases and Research Centre, Dr. H.L. Trivedi Institute of Transplantation Sciences, Civil Hospital Campus, Asarwa, Ahmedabad, Gujarat, India
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Durvasula K, Thulé PM, Sambanis A. Combinatorial insulin secretion dynamics of recombinant hepatic and enteroendocrine cells. Biotechnol Bioeng 2011; 109:1074-82. [PMID: 22094821 DOI: 10.1002/bit.24373] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Accepted: 10/31/2011] [Indexed: 12/29/2022]
Abstract
One of the most promising cell-based therapies for combating insulin-dependent diabetes entails the use of genetically engineered non-β cells that secrete insulin in response to physiologic stimuli. A normal pancreatic β cell secretes insulin in a biphasic manner in response to glucose. The first phase is characterized by a transient stimulation of insulin to rapidly lower the blood glucose levels, which is followed by a second phase of insulin secretion to sustain the lowered blood glucose levels over a longer period of time. Previous studies have demonstrated hepatic and enteroendocrine cells to be appropriate hosts for recombinant insulin expression. Due to different insulin secretion kinetics from these cells, we hypothesized that a combination of the two cell types would mimic the biphasic insulin secretion of normal β cells with higher fidelity than either cell type alone. In this study, insulin secretion experiments were conducted with two hepatic cell lines (HepG2 and H4IIE) transduced with 1 of 3 adenoviruses expressing the insulin transgene and with a stably transfected recombinant intestinal cell line (GLUTag-INS). Insulin secretion was stimulated by exposing the cells to glucose only (hepatic cells), meat hydrolysate only (GLUTag-INS), or to a cocktail of the two secretagogues. It was found experimentally that the recombinant hepatic cells secreted insulin in a more sustained manner, whereas the recombinant intestinal cell line exhibited rapid insulin secretion kinetics upon stimulation. The insulin secretion profiles were computationally combined at different cell ratios to arrive at the combinatorial kinetics. Results indicate that combinations of these two cell types allow for tuning the first and second phase of insulin secretion better than either cell type alone. This work provides the basic framework in understanding the secretion kinetics of the combined system and advances it towards preclinical studies.
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Affiliation(s)
- Kiranmai Durvasula
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia, USA
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Rasouli M, Ahmad Z, Omar AR, Allaudin ZN. Engineering an L-cell line that expresses insulin under the control of the glucagon-like peptide-1 promoter for diabetes treatment. BMC Biotechnol 2011; 11:99. [PMID: 22047106 PMCID: PMC3229441 DOI: 10.1186/1472-6750-11-99] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Accepted: 11/03/2011] [Indexed: 11/14/2022] Open
Abstract
Background Diabetes mellitus is a complicated disease with a pathophysiology that includes hyperinsulinemia, hyperglycemia and other metabolic impairments leading to many clinical complications. It is necessary to develop appropriate treatments to manage the disease and reduce possible acute and chronic side effects. The advent of gene therapy has generated excitement in the medical world for the possible application of gene therapy in the treatment of diabetes. The glucagon-like peptide-1 (GLP-1) promoter, which is recognised by gut L-cells, is an appealing candidate for gene therapy purposes. The specific properties of L-cells suggest that L-cells and the GLP-1 promoter would be useful for diabetes therapy approaches. Results In this study, L-cells were isolated from a primary intestinal cell line to create suitable target cells for insulin expression studies. The isolated cells displayed L-cell properties and were therefore used as an L-cell surrogate. Next, the isolated L-cells were transfected with the recombinant plasmid consisting of an insulin gene located downstream of the GLP-1 promoter. The secretion tests revealed that an increase in glucose concentration from 5 mM to 25 mM induced insulin gene expression in the L-cells by 2.7-fold. Furthermore, L-cells quickly responded to the glucose stimulation; the amount of insulin protein increased 2-fold in the first 30 minutes and then reached a plateau after 90 minutes. Conclusion Our data showed that L-cells efficiently produced the mature insulin protein. In addition, the insulin protein secretion was positively regulated with glucose induction. In conclusion, GLP-1 promoter and L-cell could be potential candidates for diabetes gene therapy agents.
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Affiliation(s)
- Mina Rasouli
- Laboratory of Vaccines and Immunotherapeutics, Institute of Bioscience, Universiti Putra Malaysia, UPM Serdang, Selangor, Malaysia
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14
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Abstract
Multiple approaches have been investigated with the ultimate goal of providing insulin independence to patients with either type 1 or type 2 diabetes. Approaches to produce insulin-secreting cells in culture, convert non-β-cells into functional β-cells or engineer autologous cells to express and secrete insulin in a meal-responsive manner have all been described. This research has been facilitated by significant improvements in both viral and non-viral gene delivery approaches that have enabled new experimental strategies. Many studies have examined possible avenues to confer islet cytoprotection against immune rejection, inflammation and apoptosis by genetic manipulation of islet cells prior to islet transplantation. Here we review several reports based on the reprogramming of pancreas and gut endocrine cells to treat diabetes.
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Affiliation(s)
- E Tudurí
- Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada
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15
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Mangian HF, Tappenden KA. Butyrate increases GLUT2 mRNA abundance by initiating transcription in Caco2-BBe cells. JPEN J Parenter Enteral Nutr 2010; 33:607-17; discussion 617. [PMID: 19892901 DOI: 10.1177/0148607109336599] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
BACKGROUND Glucose transporter 2 (GLUT2) is a high-capacity, facilitative intestinal monosaccharide transporter, known to be upregulated by short-chain fatty acids (SCFAs) derived from the intestinal microbiota during fermentation. Understanding the mechanisms regulating intestinal function is important to optimize therapies for patients with intestinal failure and ultimately reduce their dependence on parenteral nutrition. OBJECTIVE The objective was to examine the mechanism regulating the underlying response of GLUT2 to the SCFA butyrate. METHODS GLUT2 messenger RNA (mRNA) abundance was measured in differentiated Caco2-BBe monolayers treated for 0.5-24 hours with 0-20 mM butyrate using quantitative reverse transcription-polymerase chain reaction. Activation of the human GLUT2 promoter was measured using luciferase reporting in transiently transfected Caco2-BBe monolayers. RESULTS GLUT2 mRNA abundance was higher (P < .0001) with 1-4 hours of exposure to 2.5, 7.5, and 10 mM butyrate. Butyrate induced (P < .0001) promoter activity in a dose-dependent fashion. Analysis of the GLUT2 promoter indicated that regions -282/+522, -216/+522, and -145/+522 had a heightened (P < .05) response to butyrate compared with 1135/+522 and 564/+522. CONCLUSIONS Butyrate upregulates GLUT2 mRNA abundance in Caco2-BBe monolayers by activating specific regions within the human GLUT2 promoter. These results identify a cellular mechanism wherein butyrate upregulates intestinal absorption that may be relevant to patients with reduced function. Additional work is necessary to understand cellular targets of butyrate therapy and define clinically appropriate means of providing such strategies, such as consuming prebiotics and probiotics.
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Affiliation(s)
- Heather F Mangian
- Division of Nutritional Sciences, University of Illinois at Champaign-Urbana, Urbana, Illinois, USA
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Unniappan S, Wideman RD, Donald C, Gunn V, Wall JL, Zhang QX, Webber TD, Cheung AT, Kieffer TJ. Treatment of diabetes by transplantation of drug-inducible insulin-producing gut cells. J Mol Med (Berl) 2009; 87:703-12. [DOI: 10.1007/s00109-009-0465-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2008] [Revised: 02/25/2009] [Accepted: 03/19/2009] [Indexed: 10/20/2022]
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Murphy R, Tura A, Clark PM, Holst JJ, Mari A, Hattersley AT. Glucokinase, the pancreatic glucose sensor, is not the gut glucose sensor. Diabetologia 2009; 52:154-9. [PMID: 18974968 DOI: 10.1007/s00125-008-1183-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2008] [Accepted: 10/01/2008] [Indexed: 10/21/2022]
Abstract
AIMS/HYPOTHESIS The incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotrophic peptide (GIP) are released from intestinal endocrine cells in response to luminal glucose. Glucokinase is present in these cells and has been proposed as a glucose sensor. The physiological role of glucokinase can be tested using individuals with heterozygous glucokinase gene (GCK) mutations. If glucokinase is the gut glucose sensor, GLP-1 and GIP secretion during a 75 g OGTT would be lower in GCK mutation carriers compared with controls. METHODS We compared GLP-1 and GIP concentrations measured at five time-points during a 75 g OGTT in 49 participants having GCK mutations with those of 28 familial controls. Mathematical modelling of glucose, insulin and C-peptide was used to estimate basal insulin secretion rate (BSR), total insulin secretion (TIS), beta cell glucose sensitivity, potentiation factor and insulin secretion rate (ISR). RESULTS GIP and GLP-1 profiles during the OGTT were similar in GCK mutation carriers and controls (p = 0.52 and p = 0.44, respectively). Modelled variables of beta cell function showed a reduction in beta cell glucose sensitivity (87 pmol min(-1) m(-2) [mmol/l](-1) [95% CI 66-108] vs 183 pmol min(-1) m(-2) [mmol/l](-1) [95% CI 155-211], p < 0.001) and potentiation factor (1.5 min [95% CI 1.2-1.8] vs 2.2 min [95% CI 1.8-2.7], p = 0.007) but no change in BSR or TIS. The glucose/ISR curve was right-shifted in GCK mutation carriers. CONCLUSIONS/INTERPRETATION Glucokinase, the major pancreatic glucose sensor, is not the main gut glucose sensor. By modelling OGTT data in GCK mutation carriers we were able to distinguish a specific beta cell glucose-sensing defect. Our data suggest a reduction in potentiation of insulin secretion by glucose that is independent of differences in incretin hormone release.
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Affiliation(s)
- R Murphy
- Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
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Sim JY, Kim JH, Ahn YB, Song KH, Han JH, Cha BY, Lee SK, Moon SD. Relationship of traditional and nontraditional cardiovascular risk factors to coronary artery calcium in type 2 diabetes. KOREAN DIABETES JOURNAL 2009. [DOI: 10.4093/kdj.2009.33.6.466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Ju-Yeon Sim
- Department of Internal Medicine, Incheon St. Mary's Hospital, The Catholic University of Korea, Incheon, Korea
| | - Ju-Hee Kim
- Department of Internal Medicine, Incheon St. Mary's Hospital, The Catholic University of Korea, Incheon, Korea
| | - Yu-Bae Ahn
- Department of Internal Medicine, Incheon St. Mary's Hospital, The Catholic University of Korea, Incheon, Korea
| | - Ki-Ho Song
- Department of Internal Medicine, Incheon St. Mary's Hospital, The Catholic University of Korea, Incheon, Korea
| | - Je-Ho Han
- Department of Internal Medicine, Incheon St. Mary's Hospital, The Catholic University of Korea, Incheon, Korea
| | - Bong-Yun Cha
- Department of Internal Medicine, Incheon St. Mary's Hospital, The Catholic University of Korea, Incheon, Korea
| | - Sook-Kyung Lee
- Research Institute of Immunobiology, The Catholic University of Korea, Seoul, Korea
| | - Sung-Dae Moon
- Department of Internal Medicine, Incheon St. Mary's Hospital, The Catholic University of Korea, Incheon, Korea
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Chen NKF, Wong JS, Kee IHC, Lai SH, Thng CH, Ng WH, Ng RTH, Tan SY, Lee SY, Tan MEH, Sivalingam J, Chow PKH, Kon OL. Nonvirally modified autologous primary hepatocytes correct diabetes and prevent target organ injury in a large preclinical model. PLoS One 2008; 3:e1734. [PMID: 18320053 PMCID: PMC2249706 DOI: 10.1371/journal.pone.0001734] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2007] [Accepted: 01/22/2008] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Current gene- and cell-based therapies have significant limitations which impede widespread clinical application. Taking diabetes mellitus as a paradigm, we have sought to overcome these limitations by ex vivo electrotransfer of a nonviral insulin expression vector into primary hepatocytes followed by immediate autologous reimplantation in a preclinical model of diabetes. METHODS AND RESULTS In a single 3-hour procedure, hepatocytes were isolated from a surgically resected liver wedge, electroporated with an insulin expression plasmid ex vivo and reimplanted intraparenchymally under ultrasonic guidance into the liver in each of 10 streptozotocin-induced diabetic Yorkshire pigs. The vector was comprised of a bifunctional, glucose-responsive promoter linked to human insulin cDNA. Ambient glucose concentrations appropriately altered human insulin mRNA expression and C-peptide secretion within minutes in vitro and in vivo. Treated swine showed correction of hyperglycemia, glucose intolerance, dyslipidemia and other metabolic abnormalities for > or = 47 weeks. Metabolic correction correlated significantly with the number of hepatocytes implanted. Importantly, we observed no hypoglycemia even under fasting conditions. Direct intrahepatic implantation of hepatocytes did not alter biochemical indices of liver function or induce abnormal hepatic lobular architecture. About 70% of implanted hepatocytes functionally engrafted, appeared histologically normal, retained vector DNA and expressed human insulin for > or = 47 weeks. Based on structural tissue analyses and transcriptome data, we showed that early correction of diabetes attenuated and even prevented pathological changes in the eye, kidney, liver and aorta. CONCLUSIONS We demonstrate that autologous hepatocytes can be efficiently, simply and safely modified by electroporation of a nonviral vector to express, process and secrete insulin durably. This strategy, which achieved significant and sustained therapeutic efficacy in a large preclinical model without adverse effects, warrants consideration for clinical development especially as it could have broader future applications for the treatment of other acquired and inherited diseases for which systemic reconstitution of a specific protein deficiency is critical.
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Affiliation(s)
- Nelson K. F. Chen
- Division of Medical Sciences, National Cancer Centre, Singapore, Republic of Singapore
| | - Jen San Wong
- Division of Medical Sciences, National Cancer Centre, Singapore, Republic of Singapore
- Department of General Surgery, Singapore General Hospital, Singapore, Republic of Singapore
| | - Irene H. C. Kee
- Department of Experimental Surgery, Singapore General Hospital, Singapore, Republic of Singapore
| | - Siang Hui Lai
- Centre for Forensic Medicine, Health Sciences Authority, Singapore, Republic of Singapore
| | - Choon Hua Thng
- Department of Oncologic Imaging, National Cancer Centre, Singapore, Republic of Singapore
| | - Wai Har Ng
- Division of Medical Sciences, National Cancer Centre, Singapore, Republic of Singapore
| | - Robert T. H. Ng
- Department of Experimental Surgery, Singapore General Hospital, Singapore, Republic of Singapore
| | - Soo Yong Tan
- Department of Pathology, Singapore General Hospital, Singapore, Republic of Singapore
| | - Shu Yen Lee
- Singapore National Eye Centre, Singapore, Republic of Singapore
| | - Mark E. H. Tan
- Division of Medical Sciences, National Cancer Centre, Singapore, Republic of Singapore
| | | | - Pierce K. H. Chow
- Department of General Surgery, Singapore General Hospital, Singapore, Republic of Singapore
- Department of Experimental Surgery, Singapore General Hospital, Singapore, Republic of Singapore
| | - Oi Lian Kon
- Division of Medical Sciences, National Cancer Centre, Singapore, Republic of Singapore
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Abstract
Type 1 diabetes mellitus (T1DM) is a disease that results from the selective autoimmune destruction of insulin-producing beta-cells. This disease process lends itself to cellular therapy because of the single cell nature of insulin production. Murine models have provided opportunities for the study of cellular therapies for the treatment of diabetes, including the investigation of islet transplantation, and also the possibility of stem cell therapies and islet regeneration. Studies in islet transplantation have included both allo- and xeno-transplantation and have allowed for the study of new approaches for the reversal of autoimmunity and achieving immune tolerance. Stem cells from hematopoietic sources such as bone marrow and fetal cord blood, as well as from the pancreas, intestine, liver, and spleen promise either new sources of islets or may function as stimulators of islet regeneration. This review will summarize the various cellular interventions investigated as potential treatments of T1DM.
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Affiliation(s)
- D D Lee
- Section of Transplantation, Department of Surgery, The University of Chicago, IL 60637, USA
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