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Petropavlovskaia M, Assouline-Thomas B, Cuerquis J, Zhao J, Violette-Deslauriers S, Nano E, Eliopoulos N, Rosenberg L. Characterization of MSCs expressing islet neogenesis associated protein (INGAP): INGAP secretion and cell survival in vitro and in vivo. Heliyon 2024; 10:e35372. [PMID: 39170459 PMCID: PMC11336584 DOI: 10.1016/j.heliyon.2024.e35372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 07/25/2024] [Accepted: 07/26/2024] [Indexed: 08/23/2024] Open
Abstract
Mesenchymal stem/stromal cells (MSCs) are emerging as a new therapy for diabetes. Here we investigate the properties of MSCs engineered to express Islet Neogenesis Associated Protein (INGAP) previously shown to reverse diabetes in animal models and evaluate their potential for anti-diabetic applications in mice. Mouse bone marrow-derived MSCs retrovirally transduced to co-express INGAP, Firefly Luciferase and EGFP (INGAP-MSCs), were characterized in vitro and implanted intraperitoneally (IP) into non-diabetic and diabetic C57BL/6 mice (Streptozotocin model) and tracked by live bioluminescence imaging (BLI). Distribution and survival of IP injected INGAP-MSCs differed between diabetic and non-diabetic mice, with a rapid clearance of cells in the latter, and a stronger retention (up to 4 weeks) in diabetic mice concurring with homing towards the pancreas. Interestingly, INGAP-MSCs inhibited the progression of hyperglycemia starting at day 3 and lasting for the entire 6 weeks of the study. Pursuing greater retention, we investigated the survival of INGAP-MSCs in hydrogel matrices. When mixed with Matrigel™ and injected subcutaneously into non-diabetic mice, INGAP-MSCs remained in the implant up to 16 weeks. In vitro tests in three matrices (Matrigel™, Type I Collagen and VitroGel®-MSC) demonstrated that INGAP-MSCs survive and secrete INGAP, with best results at the density of 1-2 x 106 cells/mL. However, all matrices induced spontaneous adipogenic differentiation of INGAP-MSCs in vitro and in vivo, which requires further investigation of its potential impact on MSC therapeutic properties. In summary, based on their ability to stop the rise in hyperglycemia in STZ-treated mice, INGAP-MSCs are a promising therapeutic tool against diabetes but require further research to improve cell delivery and survival.
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Affiliation(s)
- Maria Petropavlovskaia
- Lady Davis Institute for Medical Research, SMBD-Jewish General Hospital, Montreal, QC, Canada
- Department of Surgery, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada
| | | | - Jessica Cuerquis
- Lady Davis Institute for Medical Research, SMBD-Jewish General Hospital, Montreal, QC, Canada
| | - Jing Zhao
- Lady Davis Institute for Medical Research, SMBD-Jewish General Hospital, Montreal, QC, Canada
| | - Shaun Violette-Deslauriers
- Lady Davis Institute for Medical Research, SMBD-Jewish General Hospital, Montreal, QC, Canada
- Department of Surgery, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada
| | - Eni Nano
- Lady Davis Institute for Medical Research, SMBD-Jewish General Hospital, Montreal, QC, Canada
- Department of Surgery, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada
| | - Nicoletta Eliopoulos
- Lady Davis Institute for Medical Research, SMBD-Jewish General Hospital, Montreal, QC, Canada
- Department of Surgery, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada
| | - Lawrence Rosenberg
- Lady Davis Institute for Medical Research, SMBD-Jewish General Hospital, Montreal, QC, Canada
- Department of Surgery, Faculty of Medicine and Health Sciences, McGill University, Montreal, QC, Canada
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Algañarás M, Román CL, Gagliardino JJ, Maiztegui B, Flores LE. Structural modifications of INGAP-PP present in HTD4010 peptide potentiate its effect on rat islet gene expression and insulin secretion. Peptides 2024; 173:171148. [PMID: 38215942 DOI: 10.1016/j.peptides.2024.171148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 12/28/2023] [Accepted: 01/02/2024] [Indexed: 01/14/2024]
Abstract
Type 2 diabetes (T2D) is characterized by peripheral insulin resistance and altered insulin secretion due to a progressive loss of β-cell mass and function. Today, most antidiabetic agents are designed to resolve impaired insulin secretion and/or insulin resistance, and only GLP-1-based formulations contribute to stopping the decline in β-cell mass. HTD4010, a peptide carrying two modifications of the amino acid sequence of INGAP-PP (N-terminus acetylation and substitution of Asn13 by Ala) showed greater plasma stability and could be a good candidate for proposal as a drug that could improve β cell mass and function lost in T2D. In the present study, we showed that HTD4010 included in the culture media of normal rat islets at a dose 100 times lower than that used for INGAP-PP was able to modulate, in the same way as the original peptide, both insulin secretion in response to glucose and the expression of key genes related to insular function, insulin and leptin intracellular pathways, neogenesis, apoptosis, and inflammatory response. Our results confirm the positive effect of HTD4010 on β-cell function and gene expression of factors involved in the maintenance of β-cell mass. Although new assays in animal models of prediabetes and T2D must be performed to be conclusive, our results are very encouraging, and they suggest that the use of HTD4010 at a dose 100 times lower than that of INGAP-PP could minimize its side effects in a future clinical trial.
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Affiliation(s)
- Macarena Algañarás
- CENEXA. Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET, CeAs CICPBA), Facultad de Ciencias Médicas UNLP, La Plata, Argentina
| | - Carolina L Román
- CENEXA. Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET, CeAs CICPBA), Facultad de Ciencias Médicas UNLP, La Plata, Argentina
| | - Juan J Gagliardino
- CENEXA. Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET, CeAs CICPBA), Facultad de Ciencias Médicas UNLP, La Plata, Argentina
| | - Bárbara Maiztegui
- CENEXA. Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET, CeAs CICPBA), Facultad de Ciencias Médicas UNLP, La Plata, Argentina
| | - Luis E Flores
- CENEXA. Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET, CeAs CICPBA), Facultad de Ciencias Médicas UNLP, La Plata, Argentina.
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Romero A, Heidenreich AC, Román CL, Algañarás M, Nazer E, Gagliardino JJ, Maiztegui B, Flores LE, Rodríguez-Seguí SA. Transcriptional signature of islet neogenesis-associated protein peptide-treated rat pancreatic islets reveals induction of novel long non-coding RNAs. Front Endocrinol (Lausanne) 2023; 14:1226615. [PMID: 37842306 PMCID: PMC10570750 DOI: 10.3389/fendo.2023.1226615] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Accepted: 09/06/2023] [Indexed: 10/17/2023] Open
Abstract
Background Diabetes mellitus is characterized by chronic hyperglycemia with loss of β-cell function and mass. An attractive therapeutic approach to treat patients with diabetes in a non-invasive way is to harness the innate regenerative potential of the pancreas. The Islet Neogenesis-Associated Protein pentadecapeptide (INGAP-PP) has been shown to induce β-cell regeneration and improve their function in rodents. To investigate its possible mechanism of action, we report here the global transcriptional effects induced by the short-term INGAP-PP in vitro treatment of adult rat pancreatic islets. Methods and findings Rat pancreatic islets were cultured in vitro in the presence of INGAP-PP for 4 days, and RNA-seq was generated from triplicate treated and control islet samples. We performed a de novo rat gene annotation based on the alignment of RNA-seq reads. The list of INGAP-PP-regulated genes was integrated with epigenomic data. Using the new gene annotation generated in this work, we quantified RNA-seq data profiled in INS-1 cells treated with IL1β, IL1β+Calcipotriol (a vitamin D agonist) or vehicle, and single-cell RNA-seq data profiled in rat pancreatic islets. We found 1,669 differentially expressed genes by INGAP-PP treatment, including dozens of previously unannotated rat transcripts. Genes differentially expressed by the INGAP-PP treatment included a subset of upregulated transcripts that are associated with vitamin D receptor activation. Supported by epigenomic and single-cell RNA-seq data, we identified 9 previously unannotated long noncoding RNAs (lncRNAs) upregulated by INGAP-PP, some of which are also differentially regulated by IL1β and vitamin D in β-cells. These include Ri-lnc1, which is enriched in mature β-cells. Conclusions Our results reveal the transcriptional program that could explain the enhancement of INGAP-PP-mediated physiological effects on β-cell mass and function. We identified novel lncRNAs that are induced by INGAP-PP in rat islets, some of which are selectively expressed in pancreatic β-cells and downregulated by IL1β treatment of INS-1 cells. Our results suggest a relevant function for Ri-lnc1 in β-cells. These findings are expected to provide the basis for a deeper understanding of islet translational results from rodents to humans, with the ultimate goal of designing new therapies for people with diabetes.
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Affiliation(s)
- Agustín Romero
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), CONICET-Universidad de Buenos Aires, Ciudad Universitaria, Buenos Aires, Argentina
- Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Ana C. Heidenreich
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), CONICET-Universidad de Buenos Aires, Ciudad Universitaria, Buenos Aires, Argentina
- Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Carolina L. Román
- Centro de Endocrinología Experimental y Aplicada (CENEXA) - Universidad Nacional de La Plata (UNLP) - CONICET- Centro Asociado a la Comisión de Investigaciones Científicas de la Provincia de Buenos Aires (CeAs CICPBA), Facultad de Ciencias Médicas UNLP, La Plata, Argentina
| | - Macarena Algañarás
- Centro de Endocrinología Experimental y Aplicada (CENEXA) - Universidad Nacional de La Plata (UNLP) - CONICET- Centro Asociado a la Comisión de Investigaciones Científicas de la Provincia de Buenos Aires (CeAs CICPBA), Facultad de Ciencias Médicas UNLP, La Plata, Argentina
| | - Ezequiel Nazer
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), CONICET-Universidad de Buenos Aires, Ciudad Universitaria, Buenos Aires, Argentina
| | - Juan J. Gagliardino
- Centro de Endocrinología Experimental y Aplicada (CENEXA) - Universidad Nacional de La Plata (UNLP) - CONICET- Centro Asociado a la Comisión de Investigaciones Científicas de la Provincia de Buenos Aires (CeAs CICPBA), Facultad de Ciencias Médicas UNLP, La Plata, Argentina
| | - Bárbara Maiztegui
- Centro de Endocrinología Experimental y Aplicada (CENEXA) - Universidad Nacional de La Plata (UNLP) - CONICET- Centro Asociado a la Comisión de Investigaciones Científicas de la Provincia de Buenos Aires (CeAs CICPBA), Facultad de Ciencias Médicas UNLP, La Plata, Argentina
| | - Luis E. Flores
- Centro de Endocrinología Experimental y Aplicada (CENEXA) - Universidad Nacional de La Plata (UNLP) - CONICET- Centro Asociado a la Comisión de Investigaciones Científicas de la Provincia de Buenos Aires (CeAs CICPBA), Facultad de Ciencias Médicas UNLP, La Plata, Argentina
| | - Santiago A. Rodríguez-Seguí
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), CONICET-Universidad de Buenos Aires, Ciudad Universitaria, Buenos Aires, Argentina
- Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
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Nano E, Petropavlovskaia M, Rosenberg L. Islet neogenesis associated protein (INGAP) protects pancreatic β cells from IL-1β and IFNγ-induced apoptosis. Cell Death Discov 2021; 7:56. [PMID: 33731692 PMCID: PMC7969959 DOI: 10.1038/s41420-021-00441-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 02/06/2021] [Accepted: 02/14/2021] [Indexed: 11/11/2022] Open
Abstract
The goal of this study was to determine whether recombinant Islet NeoGenesis Associated Protein (rINGAP) and its active core, a pentadecapeptide INGAP104-118 (Ingap-p), protect β cells against cytokine-induced death. INGAP has been shown to induce islet neogenesis in diabetic animals, to stimulate β-cell proliferation and differentiation, and to improve islet survival and function. Importantly, Ingap-p has shown promising results in clinical trials for diabetes (phase I/II). However, the full potential of INGAP and its mechanisms of action remain poorly understood. Using rat insulinoma cells RINm5F and INS-1 treated with interleukin-1β (IL-1β) and interferon-gamma (IFN-γ), we demonstrate here that both rINGAP and Ingap-p inhibit apoptosis, Caspase-3 activation, inducible nitric oxide synthase (iNOS) expression and nitric oxide (NO) production, and explore the related signaling pathways. As expected, IL-1β induced nuclear factor kappa B (NF-κB), p38, and JNK signaling, whereas interferon-gamma (IFN-γ) activated the JAK2/STAT1 pathway and potentiated the IL-1β effects. Both rINGAP and Ingap-p decreased phosphorylation of IKKα/β, IkBα, and p65, although p65 nuclear translocation was not inhibited. rINGAP, used for further analysis, also inhibited STAT3, p38, and JNK activation. Interestingly, all inhibitory effects of rINGAP were observed for the cytokine cocktail, not IL-1β alone, and were roughly equal to reversing the potentiating effects of INFγ. Furthermore, rINGAP had no effect on IL-1β/NF-κB-induced gene expression (e.g., Ccl2, Sod2) but downregulated several IFNγ-stimulated (Irf1, Socs1, Socs3) or IFNγ-potentiated (Nos2) genes. This, however, was observed again only for the cytokine cocktail, not IFNγ alone, and rINGAP did not inhibit the IFNγ-induced JAK2/STAT1 activation. Together, these intriguing results suggest that INGAP does not target either IL-1β or IFNγ individually but rather inhibits the signaling crosstalk between the two, the exact mechanism of which remains to be investigated. In summary, our study characterizes the anti-inflammatory effects of INGAP, both protein and peptide, and suggests a new therapeutic utility for INGAP in the treatment of diabetes.
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Affiliation(s)
- Eni Nano
- Lady Davis Institute for Medical Research, SMBD-Jewish General Hospital, Department of Surgery, Faculty of Medicine, McGill University, 3755, Cote Ste-Catherine Rd, Montreal, QC, H3T 1E2, Canada
| | - Maria Petropavlovskaia
- Lady Davis Institute for Medical Research, SMBD-Jewish General Hospital, Department of Surgery, Faculty of Medicine, McGill University, 3755, Cote Ste-Catherine Rd, Montreal, QC, H3T 1E2, Canada.
| | - Lawrence Rosenberg
- Lady Davis Institute for Medical Research, SMBD-Jewish General Hospital, Department of Surgery, Faculty of Medicine, McGill University, 3755, Cote Ste-Catherine Rd, Montreal, QC, H3T 1E2, Canada
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Lynn S, Ricardo Espinosa Silva Y, Diambra L, McCarthy AN, Liping L, Ru B, Román CL, Maiztegui B, Flores LE, Gagliardino JJ. A new analogue of islet neogenesis associated protein with higher structural and plasma stability. J Biomol Struct Dyn 2020; 39:766-776. [PMID: 31948367 DOI: 10.1080/07391102.2020.1714485] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Islet Neogenesis Associated Protein pentadecapeptide (INGAP-PP) increases β-cell mass and function in experimental animals. A short clinical trial also yielded promising results. However, HTD4010, a new peptide derived from INGAP-PP, was developed in order to optimize its specific effects by minimizing its side effects. To study and compare the tertiary structure, stability dynamics, and plasma stability of HTD4010, an INGAP-PP analogue. Both peptides were pre-incubated in human, rat and mouse plasma at 37 °C, and their presence was identified and quantified by high performance liquid chromatography at different time-points. GROMACS 2019 package and the Gromos 54A7 force field were used to evaluate overall correlated motion of the peptide molecule during molecular dynamics simulation by essential dynamics. HTD4010 exhibited significantly larger plasma stability than INGAP-PP, and its structural stability was almost 3.36-fold higher than INGAP-PP. These results suggest that HTD4010 may facilitate longer tissue interaction, thereby developing higher potential biological effects. If so, HTD4010 may become a promising therapeutic agent to treat people with diabetes. Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Soledad Lynn
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP), UNLP-CONICET La Plata, La Plata, Argentina
| | - Yanis Ricardo Espinosa Silva
- Grupo de Bioquímica Teórica, Universidad Industrial de Santander, Bucaramanga, Colombia.,Instituto de Física de Líquidos y Sistemas Biológicos (CONICET-UNLP) Depto. Cs. Biológicas, Facultad de Ciencias. Exactas UNLP 59-789, La Plata, Argentina
| | - Luis Diambra
- Departamento de Ciencias Biológicas-Facultad de Ciencias Exactas-UNLP, Centro Regional de Estudios Genómicos (CREG), La Plata, Argentina
| | - Andrés Norman McCarthy
- Departamento de Ciencias Biológicas-Facultad de Ciencias Exactas-UNLP, Centro Regional de Estudios Genómicos (CREG), La Plata, Argentina
| | - Liu Liping
- HighTide Therapeutics, Inc., Shenzhen, Guangdong, P.R. China
| | - Bai Ru
- HighTide Therapeutics, Inc., Shenzhen, Guangdong, P.R. China
| | - Carolina Lisi Román
- CENEXA (Centro de Endocrinología Experimental y Aplicada) (UNLP-CONICET-CEAS CICPBA), Facultad de Ciencias Médicas UNLP, La Plata, Argentina
| | - Barbara Maiztegui
- CENEXA (Centro de Endocrinología Experimental y Aplicada) (UNLP-CONICET-CEAS CICPBA), Facultad de Ciencias Médicas UNLP, La Plata, Argentina
| | - Luis Emilio Flores
- CENEXA (Centro de Endocrinología Experimental y Aplicada) (UNLP-CONICET-CEAS CICPBA), Facultad de Ciencias Médicas UNLP, La Plata, Argentina
| | - Juan José Gagliardino
- CENEXA (Centro de Endocrinología Experimental y Aplicada) (UNLP-CONICET-CEAS CICPBA), Facultad de Ciencias Médicas UNLP, La Plata, Argentina
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Román CL, Maiztegui B, Mencucci MV, Ahrtz L, Algañarás M, Del Zotto H, Gagliardino JJ, Flores LE. Effects of islet neogenesis associated protein depend on vascular endothelial growth factor gene expression modulated by hypoxia-inducible factor 1-alpha. Peptides 2019; 117:170090. [PMID: 31121197 DOI: 10.1016/j.peptides.2019.05.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 05/13/2019] [Accepted: 05/14/2019] [Indexed: 12/18/2022]
Abstract
BACKGROUND Pharmacology has provided efficient tools to improve insulin effect/secretion but the decrease in β-cell mass remains elusive. INGAP-PP could provide a therapeutic alternative to meet that challenge. AIM To further understand the mechanism that links INGAP-PP effects upon β-cell mass and function with islet angiogenesis. METHODOLOGY Normal male Wistar rats were divided into 2 groups and injected with a single dose of 100 mg/Kg suramin or saline. Both groups were divided into 2 subgroups that received daily doses of 2 mg/kg INGAP-PP or saline for ten days. Plasma glucose, triacylglycerol, TBARS, and insulin levels were measured. Pancreas immunomorphometric analyses were also performed. Pancreatic islets were isolated to measure glucose-stimulated insulin secretion (GSIS). Specific islet mRNA levels were studied by qRT-PCR. Statistical analysis was done using ANOVA. RESULTS No differences were recorded in body weight, food intake, or any other plasma parameter measured in all groups. Islets from INGAP-PP-treated rats significantly increased GSIS, β-cell mass, and mRNA levels of Bcl-2, Ngn-3, VEGF-A, VEGF-R2, CD31, Ang1 and Ang2, Laminin β-1, and Integrin β-1, and decreased mRNA levels of Caspase-8, Bad, and Bax. Islets from suramin-treated rats showed significant opposite effects, but INGAPP-PP administration rescued most of the suramin effects in animals treated with both compounds. CONCLUSION Our results reinforce the concept that INGAP-PP enhances insulin secretion and β-cell mass, acting through PI3K/Akt/mTOR pathways and simultaneously activating angiogenesis through HIF-1α-mediated VEGF-A secretion. Therefore, INGAP-PP might be a suitable antidiabetic agent able to overcome two major alterations present in T2D.
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Affiliation(s)
- C L Román
- CENEXA. Centro de Endocrinología Experimental y Aplicada (UNLP-CONICETLa Plata), Facultad de Ciencias Médicas UNLP. 60 y 120 (s/n) 4to piso 1900 La Plata, Argentina
| | - B Maiztegui
- CENEXA. Centro de Endocrinología Experimental y Aplicada (UNLP-CONICETLa Plata), Facultad de Ciencias Médicas UNLP. 60 y 120 (s/n) 4to piso 1900 La Plata, Argentina
| | - M V Mencucci
- CENEXA. Centro de Endocrinología Experimental y Aplicada (UNLP-CONICETLa Plata), Facultad de Ciencias Médicas UNLP. 60 y 120 (s/n) 4to piso 1900 La Plata, Argentina
| | - L Ahrtz
- CENEXA. Centro de Endocrinología Experimental y Aplicada (UNLP-CONICETLa Plata), Facultad de Ciencias Médicas UNLP. 60 y 120 (s/n) 4to piso 1900 La Plata, Argentina
| | - M Algañarás
- CENEXA. Centro de Endocrinología Experimental y Aplicada (UNLP-CONICETLa Plata), Facultad de Ciencias Médicas UNLP. 60 y 120 (s/n) 4to piso 1900 La Plata, Argentina
| | - H Del Zotto
- CENEXA. Centro de Endocrinología Experimental y Aplicada (UNLP-CONICETLa Plata), Facultad de Ciencias Médicas UNLP. 60 y 120 (s/n) 4to piso 1900 La Plata, Argentina
| | - J J Gagliardino
- CENEXA. Centro de Endocrinología Experimental y Aplicada (UNLP-CONICETLa Plata), Facultad de Ciencias Médicas UNLP. 60 y 120 (s/n) 4to piso 1900 La Plata, Argentina
| | - L E Flores
- CENEXA. Centro de Endocrinología Experimental y Aplicada (UNLP-CONICETLa Plata), Facultad de Ciencias Médicas UNLP. 60 y 120 (s/n) 4to piso 1900 La Plata, Argentina.
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Casasnovas J, Jo Y, Rao X, Xuei X, Brown ME, Kua KL. High glucose alters fetal rat islet transcriptome and induces progeny islet dysfunction. J Endocrinol 2019; 240:309-323. [PMID: 30508415 DOI: 10.1530/joe-18-0493] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 11/30/2018] [Indexed: 12/11/2022]
Abstract
Offspring of diabetic mothers are susceptible to developing type 2 diabetes due to pancreatic islet dysfunction. However, the initiating molecular pathways leading to offspring pancreatic islet dysfunction are unknown. We hypothesized that maternal hyperglycemia alters offspring pancreatic islet transcriptome and negatively impacts offspring islet function. We employed an infusion model capable of inducing localized hyperglycemia in fetal rats residing in the left uterine horn, thus avoiding other factors involved in programming offspring pancreatic islet health. While maintaining euglycemia in maternal dams and right uterine horn control fetuses, hyperglycemic fetuses in the left uterine horn had higher serum insulin and pancreatic beta cell area. Upon completing infusion from GD20 to 22, RNA sequencing was performed on GD22 islets to identify the hyperglycemia-induced altered gene expression. Ingenuity pathway analysis of the altered transcriptome found that diabetes mellitus and inflammation/cell death pathways were enriched. Interestingly, the downregulated genes modulate more diverse biological processes, which includes responses to stimuli and developmental processes. Next, we performed ex and in vivo studies to evaluate islet cell viability and insulin secretory function in weanling and adult offspring. Pancreatic islets of weanlings exposed to late gestation hyperglycemia had decreased cell viability in basal state and glucose-induced insulin secretion. Lastly, adult offspring exposed to in utero hyperglycemia also exhibited glucose intolerance and insulin secretory dysfunction. Together, our results demonstrate that late gestational hyperglycemia alters the fetal pancreatic islet transcriptome and increases offspring susceptibility to developing pancreatic islet dysfunction.
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Affiliation(s)
- Jose Casasnovas
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Yunhee Jo
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Xi Rao
- Center for Medical Genomics, Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Xiaoling Xuei
- Center for Medical Genomics, Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Mary E Brown
- The Indiana Center for Biological Microscopy, Division of Nephrology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Kok Lim Kua
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, USA
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Román CL, Maiztegui B, Del Zotto H, Gagliardino JJ, Flores LE. INGAP-PP effects on β-cell mass and function are related to its positive effect on islet angiogenesis and VEGFA production. Mol Cell Endocrinol 2018; 470:269-280. [PMID: 29146554 DOI: 10.1016/j.mce.2017.11.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 11/10/2017] [Accepted: 11/10/2017] [Indexed: 01/09/2023]
Abstract
Our aim was to determine whether islet angiogenesis and VEGFA production/release participate in the mechanism by which INGAP-PP enhances β-cell function and mass. We used two models: a) in vivo (normal rats injected with INGAP-PP for 10 days) and b) in vitro (normal islets cultured for 4 days with INGAP-PP, VEGFA, Rapamycin, and the specific VEGF-Receptor inhibitor, SU5416). INGAP-PP administration enhanced insulin secretion, β-cell mass, islet vascularization, and angiogenesis without affecting glucose homeostasis. Normal islets cultured with INGAP-PP and VEGFA increased insulin and VEGFA secretion while apoptosis decreased. INGAP-PP-induced effects were prevented by both Rapamycin and SU5416. INGAP-PP effects on β-cell mass and function were significantly associated with a positive effect on islet angiogenesis and VEGFA production/release. VEGF-A possibly potentiates INGAP-PP effect through mTORC pathway.
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Affiliation(s)
- Carolina Lisi Román
- CENEXA, Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET La Plata), Facultad de Ciencias Médicas UNLP, 60 y 120 (s/n) 4to piso, 1900 La Plata, Argentina
| | - Bárbara Maiztegui
- CENEXA, Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET La Plata), Facultad de Ciencias Médicas UNLP, 60 y 120 (s/n) 4to piso, 1900 La Plata, Argentina
| | - Héctor Del Zotto
- CENEXA, Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET La Plata), Facultad de Ciencias Médicas UNLP, 60 y 120 (s/n) 4to piso, 1900 La Plata, Argentina
| | - Juan José Gagliardino
- CENEXA, Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET La Plata), Facultad de Ciencias Médicas UNLP, 60 y 120 (s/n) 4to piso, 1900 La Plata, Argentina
| | - Luis Emilio Flores
- CENEXA, Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET La Plata), Facultad de Ciencias Médicas UNLP, 60 y 120 (s/n) 4to piso, 1900 La Plata, Argentina.
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Villagarcía HG, Román CL, Castro MC, González LA, Ronco MT, Francés DE, Massa ML, Maiztegui B, Flores LE, Gagliardino JJ, Francini F. Liver carbohydrates metabolism: A new islet-neogenesis associated protein peptide (INGAP-PP) target. Peptides 2018; 101:44-50. [PMID: 29305881 DOI: 10.1016/j.peptides.2018.01.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 12/22/2017] [Accepted: 01/02/2018] [Indexed: 11/20/2022]
Abstract
Islet-Neogenesis Associated Protein-Pentadecapeptide (INGAP-PP) increases β-cell mass and enhances glucose and amino acids-induced insulin secretion. Our aim was to demonstrate its effect on liver metabolism. For that purpose, adult male Wistar rats were injected twice-daily (10 days) with saline solution or INGAP-PP (250 μg). Thereafter, serum glucose, triglyceride and insulin levels were measured and homeostasis model assessment (HOMA-IR) and hepatic insulin sensitivity (HIS) were determined. Liver glucokinase and glucose-6-phosphatase (G-6-Pase) expression and activity, phosphoenolpyruvate carboxykinase (PEPCK) expression, phosphofructokinase-2 (PFK-2) protein content, P-Akt/Akt and glycogen synthase kinase-3β (P-GSK3/GSK3) protein ratios and glycogen deposit were also determined. Additionally, glucokinase activity and G-6-Pase and PEPCK gene expression were also determined in isolated hepatocytes from normal rats incubated with INGAP-PP (5 μg/ml). INGAP-PP administration did not modify any of the serum parameters tested but significantly increased activity of liver glucokinase and the protein level of its cytosolic activator, PFK-2. Conversely, INGAP-PP treated rats decreased gene expression and enzyme activity of gluconeogenic enzymes, G-6-Pase and PEPCK. They also showed a higher glycogen deposit and P-GSK3/GSK3 and P-Akt/Akt ratio. In isolated hepatocytes, INGAP-PP increased GK activity and decreased G-6-Pase and PEPCK expression. These results demonstrate a direct effect of INGAP-PP on the liver acting through P-Akt signaling pathway. INGAP-PP enhances liver glucose metabolism and deposit and reduces its production/output, thereby contributing to maintain normal glucose homeostasis. These results reinforce the concept that INGAP-PP might become a useful tool to treat people with impaired islet/liver glucose metabolism as it occurs in T2D.
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Affiliation(s)
- Hernán Gonzalo Villagarcía
- CENEXA, Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET La Plata), Facultad de Ciencias Médicas, 60 y 120, 1900 La Plata, Argentina
| | - Carolina Lisi Román
- CENEXA, Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET La Plata), Facultad de Ciencias Médicas, 60 y 120, 1900 La Plata, Argentina
| | - María Cecilia Castro
- CENEXA, Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET La Plata), Facultad de Ciencias Médicas, 60 y 120, 1900 La Plata, Argentina
| | - Luisa Arbeláez González
- CIC, Centro de Investigaciones Cardiovasculares (UNLP-CONICET La Plata), Facultad de Ciencias Médicas, 60 y 120, 1900 La Plata, Argentina
| | - María Teresa Ronco
- IFISE, Instituto de Fisiología Experimental (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, 2000 Rosario, Argentina
| | - Daniel Eleazar Francés
- IFISE, Instituto de Fisiología Experimental (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, 2000 Rosario, Argentina
| | - María Laura Massa
- CENEXA, Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET La Plata), Facultad de Ciencias Médicas, 60 y 120, 1900 La Plata, Argentina
| | - Bárbara Maiztegui
- CENEXA, Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET La Plata), Facultad de Ciencias Médicas, 60 y 120, 1900 La Plata, Argentina
| | - Luis Emilio Flores
- CENEXA, Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET La Plata), Facultad de Ciencias Médicas, 60 y 120, 1900 La Plata, Argentina
| | - Juan José Gagliardino
- CENEXA, Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET La Plata), Facultad de Ciencias Médicas, 60 y 120, 1900 La Plata, Argentina
| | - Flavio Francini
- CENEXA, Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET La Plata), Facultad de Ciencias Médicas, 60 y 120, 1900 La Plata, Argentina.
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Role of Islet Glucokinase, Glucose Metabolism, and Insulin Pathway in the Enhancing Effect of Islet Neogenesis-Associated Protein on Glucose-Induced Insulin Secretion. Pancreas 2015; 44:959-66. [PMID: 25906449 DOI: 10.1097/mpa.0000000000000341] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
OBJECTIVE To demonstrate the role of islet glucokinase, glucose metabolism, and intracellular insulin mediators in the enhancing effect of islet neogenesis-associated protein pentadecapeptide (INGAP-PP) on glucose-induced insulin secretion. METHODS Islets from normal rats were cultured for 4 days in the absence or presence of 10 μg/mL INGAP-PP, with/without Wortmannin or LY294002. Islets were incubated with different glucose concentrations to measure insulin secretion and content, hexokinase and glucokinase activity, glucose oxidation and utilization, glucokinase, insulin receptor, insulin receptor substrate (IRS)-1/2, and PI3K concentration and phosphorylation. RESULTS The INGAP-PP significantly increased insulin release at high but not at low glucose concentration, glucokinase activity, glucose metabolism, glucokinase, insulin receptor, IRS-2 and PI3K protein concentration, insulin receptor and IRS-1/2 tyrosine phosphorylation, and the association of p85 with IRS-1. Wortmannin and LY294002 blocked INGAP-PP effect on insulin secretion and glucokinase protein levels in a dose-dependent manner. CONCLUSIONS The enhancing effect of INGAP-PP on glucose-induced insulin release could be partly ascribed to its effect on glucokinase activity and glucose metabolism and is mainly mediated by the PI3K/AKT pathway. These results, together with the low hypoglycemia risk associated with the use of INGAP-PP, offer a new alternative for diabetes prevention and treatment.
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Islet NADPH oxidase activity modulates β-cell mass and endocrine function in rats with fructose-induced oxidative stress. Biochim Biophys Acta Gen Subj 2014; 1840:3475-82. [DOI: 10.1016/j.bbagen.2014.09.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 08/22/2014] [Accepted: 09/08/2014] [Indexed: 12/16/2022]
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Flores LE, Del Zotto H, Fragapane F, Maiztegui B, Román CL, Boschero AC, Gagliardino JJ. Islet neogenesis-associated protein (INGAP): the role of its endogenous production as a positive modulator of insulin secretion. ACTA ACUST UNITED AC 2014; 192-193:30-4. [PMID: 25160856 DOI: 10.1016/j.regpep.2014.08.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 08/13/2014] [Accepted: 08/16/2014] [Indexed: 10/24/2022]
Abstract
Islet neogenesis-associated protein (INGAP) is a peptide found in pancreatic exocrine-, duct- and islet- non-β-cells from normal hamsters. Its increase induced by either its exogenous administration or by the overexpression of its gene enhances β-cell secretory function and increases β-cell mass by a combination of stimulation of cell replication and islet neogenesis and reduction of β-cell apoptosis. We studied the potential modulatory role of endogenous INGAP in insulin secretion using two different experimental approaches. Hamster islets transfected with INGAP-small interfering RNA (INGAP-siRNA) were used to study glucose-stimulated insulin secretion (GSIS). In parallel, freshly isolated islets were incubated with high glucose and the same concentration of either a specific anti-INGAP rabbit serum or normal rabbit serum. INGAP-siRNA transfected islets reduced their INGAP mRNA and protein content by 35.1% and 47.2%, respectively whereas GSIS decreased by 25.8%. GSIS by transfected islets attained levels comparable to those recorded in control islets when INGAP pentadecapeptide (INGAP-PP) was added to the culture medium. INGAP antibody in the medium decreased significantly GSIS in a dose-dependent manner. These results indicate that endogenous INGAP plays a "physiological" positive modulatory role in insulin secretion, supporting its possible use in the treatment of prediabetes and Type 2 diabetes.
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Affiliation(s)
- Luis E Flores
- CENEXA, Center of Experimental and Applied Endocrinology, National University of La Plata, La Plata National Research Council, PAHO/WHO Collaborating Center, School of Medical Sciences, 1900 La Plata, Argentina.
| | - Héctor Del Zotto
- CENEXA, Center of Experimental and Applied Endocrinology, National University of La Plata, La Plata National Research Council, PAHO/WHO Collaborating Center, School of Medical Sciences, 1900 La Plata, Argentina
| | - Florencia Fragapane
- CENEXA, Center of Experimental and Applied Endocrinology, National University of La Plata, La Plata National Research Council, PAHO/WHO Collaborating Center, School of Medical Sciences, 1900 La Plata, Argentina
| | - Bárbara Maiztegui
- CENEXA, Center of Experimental and Applied Endocrinology, National University of La Plata, La Plata National Research Council, PAHO/WHO Collaborating Center, School of Medical Sciences, 1900 La Plata, Argentina
| | - Carolina L Román
- CENEXA, Center of Experimental and Applied Endocrinology, National University of La Plata, La Plata National Research Council, PAHO/WHO Collaborating Center, School of Medical Sciences, 1900 La Plata, Argentina
| | - Antonio C Boschero
- Department of Physiology and Biophysics, Institute of Biology, State University of Campinas, UNICAMP, Campinas 13083-970, Brazil
| | - Juan J Gagliardino
- CENEXA, Center of Experimental and Applied Endocrinology, National University of La Plata, La Plata National Research Council, PAHO/WHO Collaborating Center, School of Medical Sciences, 1900 La Plata, Argentina
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TNF-like weak inducer of apoptosis (TWEAK) promotes beta cell neogenesis from pancreatic ductal epithelium in adult mice. PLoS One 2013; 8:e72132. [PMID: 23991053 PMCID: PMC3753348 DOI: 10.1371/journal.pone.0072132] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 07/05/2013] [Indexed: 12/01/2022] Open
Abstract
Aim/Hypothesis The adult mammalian pancreas has limited ability to regenerate in order to restore adequate insulin production from multipotent progenitors, the identity and function of which remain poorly understood. Here we test whether the TNF family member TWEAK (TNF-like weak inducer of apoptosis) promotes β-cell neogenesis from proliferating pancreatic ductal epithelium in adult mice. Methods C57Bl/6J mice were treated with Fc-TWEAK and pancreas harvested at different time points for analysis by histology and immunohistochemistry. For lineage tracing, 4 week old double transgenic mice CAII-CreERTM: R26R-eYFP were implanted with tamoxifen pellet, injected with Fc-TWEAK or control Ig twice weekly and analyzed at day 18 for TWEAK-induced duct cell progeny by costaining for insulin and YFP. The effect of TWEAK on pancreatic regeneration was determined by pancytokeratin immunostaining of paraffin embedded sections from wildtype and TWEAK receptor (Fn14) deficient mice after Px. Results TWEAK stimulates proliferation of ductal epithelial cells through its receptor Fn14, while it has no mitogenic effect on pancreatic α- or β-cells or acinar cells. Importantly, TWEAK induces transient expression of endogenous Ngn3, a master regulator of endocrine cell development, and induces focal ductal structures with characteristics of regeneration foci. In addition, we identify by lineage tracing TWEAK-induced pancreatic β-cells derived from pancreatic duct epithelial cells. Conversely, we show that Fn14 deficiency delays formation of regenerating foci after Px and limits their expansion. Conclusions/Interpretation We conclude that TWEAK is a novel factor mediating pancreatic β-cell neogenesis from ductal epithelium in normal adult mice.
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Islet neogenesis-associated protein (INGAP)-positive cell mass, β-cell mass, and insulin secretion: their relationship during the fetal and neonatal periods. Pancreas 2013; 42:422-8. [PMID: 23303201 DOI: 10.1097/mpa.0b013e318264c7bd] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
OBJECTIVES To study the chronological appearance of pancreatic islet neogenesis-associated protein (INGAP)-positive cells and its correlation with the increase in β-cell mass and function in fetal and neonatal rats. METHODS Normal Wistar rat embryos (E) at gestational days 15, 17, and 19 (E15, E17, E19) and 7-day-old postnatal rats (P7) were humanely killed to determine body and pancreas weight; blood glucose; glucose and arginine-induced insulin secretion; real-time polymerase chain reaction of Pdx1 and Ngn3; quantitative immunomorphometric analysis of β-cell replication and apoptosis rate, cytokeratin and INGAP cell mass, and Pdx-1- and Ngn3-positive cells. RESULTS Body and pancreas weight increased with age (P7 > E19 > E17 > E15; P < 0.05). Neonates had higher blood glucose concentrations than embryos (P < 0.05). We recorded a simultaneous and significant age-dependent trend of increase in the number of β- and Pdx-1-positive cells, β- and cytokeratin-positive cell mass and β-cell capacity to release insulin in response to glucose and arginine, and decreased β-cell apoptotic rate. These changes closely paralleled the increase in INGAP-positive cell mass. CONCLUSIONS These findings suggest that INGAP exerts a positive modulatory effect on β-cell mass and its secretory function in fetal and neonatal rats, thus becoming a new component in the multifactorial regulation of such processes.
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Kapur R, Højfeldt TW, Højfeldt TW, Rønn SG, Karlsen AE, Heller RS. Short-term effects of INGAP and Reg family peptides on the appearance of small β-cells clusters in non-diabetic mice. Islets 2012; 4:40-8. [PMID: 22395480 DOI: 10.4161/isl.18659] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The Reg3 peptides INGAP-PP and human Reg3α/β (HIP) have been hypothesized to stimulate β-cell neogenesis in the pancreas. Administration of INGAP-PP has been shown to cause an increase in β-cell mass in multiple animal models, reverse streptozotocin (STZ) induced diabetes in mice and reduces HbA1c levels in type 2 diabetic humans. In this study, we have examined the ability of the INGAP-PP and HIP peptides to induce β-cell formation in vivo in normal mice through short-term administration of the peptides. We assessed the peptides ability to induce an increase in extra-islet insulin-positive cell clusters by looking at β-cell number by point counting morphometry on pancreata that had been randomized using the smooth fractionator principle in non-diabetic NMRI mice after short-term injections of the peptides (5 d). Five day continuous BrdU labeling was used to determine if the new β-cells were derived from replicating β-cells. Real time quantitative RT-PCR and immuno-histochemistry was used to analyze changes in pancreatic transcription factor expression. A 1.5- to 2-fold increase in the volume of small extra-islet insulin-positive clusters post 5 d treatment with INGAP-PP and HIP as compared with mice treated with a non-peptide control or scrambled peptide (p<0.05) (n = 7) was found. Five day continuous BrdU infusion during the 5 d period showed little or no incorporation in islets or small insulin clusters. Five days of treatment with INGAP-PP or HIP, showed a tendency toward increased levels of pancreatic progenitor markers such as Ngn3, Nkx6.1, Sox9 and Ins. These are the first studies to compare and indicate that the human Reg3 α/β (HIP) peptide has similar bioactivity in vivo as INGAP by causing formation of small β-cell clusters in extra-islet pancreatic tissue after only 5 d of treatment. Upregulation of pancreatic transcription factors may be part of the mechanism of action.
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Affiliation(s)
- Rahul Kapur
- Department of Beta Cell Regeneration; Hagedorn Research Institute; Gentofte, Denmark
| | | | | | - Sif Groth Rønn
- Department of Incretin Biology; Hagedorn Research Institute; Gentofte, Denmark
| | - Allan E Karlsen
- Department of Beta Cell Regeneration; Hagedorn Research Institute; Gentofte, Denmark
| | - R Scott Heller
- Department of Beta Cell Regeneration; Hagedorn Research Institute; Gentofte, Denmark
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Abstract
The role of aging in the pathogenesis of type 2 diabetes remains poorly understood. In the past adult β-cells were assumed to undergo frequent turnover. However, we find that β-cell turnover declines to very low levels in middle-aged mice. We therefore hypothesized that aged islets could exhibit a distinct gene expression program. We compared gene expression in islets from young mice to islets from aged mice under basal conditions. Aging was associated with differential expression of many genes in islets, including mRNAs encoding for chromatin remodeling components, RNA binding proteins, and pancreatic endocrine transcription factors. We previously observed that cell cycle entry of β-cells is severely restricted by middle age, with minimal of β-cell proliferation in response to regenerative stimuli such as 50% partial pancreatectomy. To characterize the effect of age in adaptive β-cell proliferation, we measured gene expression in islets from young mice after pancreatectomy. As expected, partial pancreatectomy induced differential expression of many genes, including those encoding Reg (regenerating) proteins. Surprisingly, partial pancreatectomy also induced expression of Reg genes in islets from aged mice, which have greatly reduced capacity for adaptive β-cell proliferation. However, there was little overlap (besides the Reg genes) in between the partial pancreatectomy induced islet genes in young mice versus old mice. Thus, partial pancreatectomy does not induce the same gene expression program in young mice vs old mice. Taken together, our results reveal that aged islets exhibit a unique gene expression signature that could contribute to the limited regenerative capacity of mature β-cells.
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Affiliation(s)
- Matthew M Rankin
- Division of Endocrinology and Diabetes, Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, PA USA
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Wang GS, Kauri LM, Patrick C, Bareggi M, Rosenberg L, Scott FW. Enhanced islet expansion by β-cell proliferation in young diabetes-prone rats fed a protective diet. J Cell Physiol 2010; 224:501-8. [DOI: 10.1002/jcp.22151] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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