1
|
Šterk M, Zhang Y, Pohorec V, Leitgeb EP, Dolenšek J, Benninger RKP, Stožer A, Kravets V, Gosak M. Network representation of multicellular activity in pancreatic islets: Technical considerations for functional connectivity analysis. PLoS Comput Biol 2024; 20:e1012130. [PMID: 38739680 PMCID: PMC11115366 DOI: 10.1371/journal.pcbi.1012130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 05/23/2024] [Accepted: 05/02/2024] [Indexed: 05/16/2024] Open
Abstract
Within the islets of Langerhans, beta cells orchestrate synchronized insulin secretion, a pivotal aspect of metabolic homeostasis. Despite the inherent heterogeneity and multimodal activity of individual cells, intercellular coupling acts as a homogenizing force, enabling coordinated responses through the propagation of intercellular waves. Disruptions in this coordination are implicated in irregular insulin secretion, a hallmark of diabetes. Recently, innovative approaches, such as integrating multicellular calcium imaging with network analysis, have emerged for a quantitative assessment of the cellular activity in islets. However, different groups use distinct experimental preparations, microscopic techniques, apply different methods to process the measured signals and use various methods to derive functional connectivity patterns. This makes comparisons between findings and their integration into a bigger picture difficult and has led to disputes in functional connectivity interpretations. To address these issues, we present here a systematic analysis of how different approaches influence the network representation of islet activity. Our findings show that the choice of methods used to construct networks is not crucial, although care is needed when combining data from different islets. Conversely, the conclusions drawn from network analysis can be heavily affected by the pre-processing of the time series, the type of the oscillatory component in the signals, and by the experimental preparation. Our tutorial-like investigation aims to resolve interpretational issues, reconcile conflicting views, advance functional implications, and encourage researchers to adopt connectivity analysis. As we conclude, we outline challenges for future research, emphasizing the broader applicability of our conclusions to other tissues exhibiting complex multicellular dynamics.
Collapse
Affiliation(s)
- Marko Šterk
- Faculty of Natural Sciences and Mathematics, University of Maribor, Maribor, Slovenia
- Faculty of Medicine, University of Maribor, Maribor, Slovenia
| | - Yaowen Zhang
- Department of Pediatrics, Department of Bioengineering, University of California, San Diego, La Jolla, California, United States of America
| | - Viljem Pohorec
- Faculty of Medicine, University of Maribor, Maribor, Slovenia
| | | | - Jurij Dolenšek
- Faculty of Natural Sciences and Mathematics, University of Maribor, Maribor, Slovenia
- Faculty of Medicine, University of Maribor, Maribor, Slovenia
| | - Richard K. P. Benninger
- Department of Bioengineering, Barbara Davis Center for Diabetes, Aurora, Colorado, United States of America
- Barbara Davis Center for Childhood Diabetes, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America
| | - Andraž Stožer
- Faculty of Medicine, University of Maribor, Maribor, Slovenia
| | - Vira Kravets
- Department of Pediatrics, Department of Bioengineering, University of California, San Diego, La Jolla, California, United States of America
- Department of Bioengineering, Jacobs School of Engineering, University of California, San Diego, La Jolla, California, United States of America
| | - Marko Gosak
- Faculty of Natural Sciences and Mathematics, University of Maribor, Maribor, Slovenia
- Faculty of Medicine, University of Maribor, Maribor, Slovenia
- Alma Mater Europaea, Maribor
| |
Collapse
|
2
|
Campbell-Thompson M, Butterworth EA, Boatwright JL, Nair MA, Nasif LH, Nasif K, Revell AY, Riva A, Mathews CE, Gerling IC, Schatz DA, Atkinson MA. Islet sympathetic innervation and islet neuropathology in patients with type 1 diabetes. Sci Rep 2021; 11:6562. [PMID: 33753784 PMCID: PMC7985489 DOI: 10.1038/s41598-021-85659-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 03/04/2021] [Indexed: 02/07/2023] Open
Abstract
Dysregulation of glucagon secretion in type 1 diabetes (T1D) involves hypersecretion during postprandial states, but insufficient secretion during hypoglycemia. The sympathetic nervous system regulates glucagon secretion. To investigate islet sympathetic innervation in T1D, sympathetic tyrosine hydroxylase (TH) axons were analyzed in control non-diabetic organ donors, non-diabetic islet autoantibody-positive individuals (AAb), and age-matched persons with T1D. Islet TH axon numbers and density were significantly decreased in AAb compared to T1D with no significant differences observed in exocrine TH axon volume or lengths between groups. TH axons were in close approximation to islet α-cells in T1D individuals with long-standing diabetes. Islet RNA-sequencing and qRT-PCR analyses identified significant alterations in noradrenalin degradation, α-adrenergic signaling, cardiac β-adrenergic signaling, catecholamine biosynthesis, and additional neuropathology pathways. The close approximation of TH axons at islet α-cells supports a model for sympathetic efferent neurons directly regulating glucagon secretion. Sympathetic islet innervation and intrinsic adrenergic signaling pathways could be novel targets for improving glucagon secretion in T1D.
Collapse
Affiliation(s)
- Martha Campbell-Thompson
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL, 32610, USA. .,Department of Biomedical Engineering, College of Engineering, University of Florida, Gainesville, FL, 32610, USA.
| | - Elizabeth A Butterworth
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - J Lucas Boatwright
- Bioinformatics Core, Interdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, FL, 32610, USA
| | - Malavika A Nair
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Lith H Nasif
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Kamal Nasif
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Andy Y Revell
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Alberto Riva
- Bioinformatics Core, Interdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, FL, 32610, USA
| | - Clayton E Mathews
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Ivan C Gerling
- Department of Medicine-Endocrinology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Desmond A Schatz
- Department of Pediatrics, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Mark A Atkinson
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL, 32610, USA.,Department of Pediatrics, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| |
Collapse
|
3
|
Atkinson MA, Campbell-Thompson M, Kusmartseva I, Kaestner KH. Organisation of the human pancreas in health and in diabetes. Diabetologia 2020; 63:1966-1973. [PMID: 32894306 PMCID: PMC7565096 DOI: 10.1007/s00125-020-05203-7] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 04/24/2020] [Indexed: 02/06/2023]
Abstract
For much of the last century, our knowledge regarding the pancreas in type 1 and type 2 diabetes was largely derived from autopsy studies of individuals with these disorders or investigations utilising rodent models of either disease. While many important insights emanated from these efforts, the mode for investigation has increasingly seen change due to the availability of transplant-quality organ-donor tissues, improvements in pancreatic imaging, advances in metabolic assessments of living patients, genetic analyses, technological advances for laboratory investigation and more. As a result, many long-standing notions regarding the role for and the changes that occur in the pancreas in individuals with these disorders have come under question, while, at the same time, new issues (e.g., beta cell persistence, disease heterogeneity, exocrine contributions) have arisen. In this article, we will consider the vital role of the pancreas in human health and physiology, including discussion of its anatomical features and dual (exocrine and endocrine) functions. Specifically, we convey changes that occur in the pancreas of those with either type 1 or type 2 diabetes, with careful attention to the facets that may contribute to the pathogenesis of either disorder. Finally, we discuss the emerging unknowns with the belief that understanding the role of the pancreas in type 1 and type 2 diabetes will lead to improvements in disease diagnosis, understanding of disease heterogeneity and optimisation of treatments at a personalised level. Graphical abstract.
Collapse
Affiliation(s)
- Mark A Atkinson
- Department of Pathology, Immunology and Laboratory Medicine, College of Medicine, University of Florida Diabetes Institute, Box 100275, 1275 Center Dr., BMSB J593, Gainesville, FL, 32610, USA.
- Department of Pediatrics, University of Florida College of Medicine, Gainesville, FL, USA.
| | - Martha Campbell-Thompson
- Department of Pathology, Immunology and Laboratory Medicine, College of Medicine, University of Florida Diabetes Institute, Box 100275, 1275 Center Dr., BMSB J593, Gainesville, FL, 32610, USA
- Department of Biomedical Engineering, University of Florida College of Engineering, Gainesville, FL, USA
| | - Irina Kusmartseva
- Department of Pathology, Immunology and Laboratory Medicine, College of Medicine, University of Florida Diabetes Institute, Box 100275, 1275 Center Dr., BMSB J593, Gainesville, FL, 32610, USA
| | - Klaus H Kaestner
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| |
Collapse
|
4
|
The beneficial effects of a muscarinic agonist on pancreatic β-cells. Sci Rep 2019; 9:16180. [PMID: 31700039 PMCID: PMC6838462 DOI: 10.1038/s41598-019-52691-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 09/24/2019] [Indexed: 12/13/2022] Open
Abstract
The brain and nervous system play an important role in pancreatic β-cell function. This study investigated the role of muscarinic agonists or acetylcholine, which is the major neurotransmitter in the vagal nerve, in regulating pancreatic β-cell mass and glucose homeostasis. Administration of the muscarinic agonist bethanechol increased insulin secretion and improved glucose tolerance in insulin-receptor substrate 2 (IRS2)-knockout (IRS-2−/−) mice and diet-induced obesity mice. Oral administration of bethanechol increased β-cell mass and proliferation in wild-type mice, but not IRS-2−/− mice. The muscarinic agonist also increased the incorporation of 5-bromo-2′-deoxyuridine (BrdU) into islets isolated from wild-type mice and pancreatic β-cell line MIN6. The phosphorylation of protein kinase B (Akt) induced by oral administration of bethanechol was observed in wild-type mice, but not IRS-2−/− mice. The secretion of glucagon-like peptide-1 (GLP-1) was also stimulated by bethanechol in wild-type mice, and a GLP-1 antagonist partially inhibited the bethanechol-induced increase in β-cell mass. These results suggest that the muscarinic agonist exerted direct and indirect effects on β-cell proliferation that were dependent on the IRS-2/Akt pathway. The bethanechol-stimulated release of GLP-1 may be indirectly associated with β-cell proliferation.
Collapse
|
5
|
Jansson L, Carlsson PO. Pancreatic Blood Flow with Special Emphasis on Blood Perfusion of the Islets of Langerhans. Compr Physiol 2019; 9:799-837. [PMID: 30892693 DOI: 10.1002/cphy.c160050] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The pancreatic islets are more richly vascularized than the exocrine pancreas, and possess a 5- to 10-fold higher basal and stimulated blood flow, which is separately regulated. This is reflected in the vascular anatomy of the pancreas where islets have separate arterioles. There is also an insulo-acinar portal system, where numerous venules connect each islet to the acinar capillaries. Both islets and acini possess strong metabolic regulation of their blood perfusion. Of particular importance, especially in the islets, is adenosine and ATP/ADP. Basal and stimulated blood flow is modified by local endothelial mediators, the nervous system as well as gastrointestinal hormones. Normally the responses to the nervous system, especially the parasympathetic and sympathetic nerves, are fairly similar in endocrine and exocrine parts. The islets seem to be more sensitive to the effects of endothelial mediators, especially nitric oxide, which is a permissive factor to maintain the high basal islet blood flow. The gastrointestinal hormones with pancreatic effects mainly influence the exocrine pancreatic blood flow, whereas islets are less affected. A notable exception is incretin hormones and adipokines, which preferentially affect islet vasculature. Islet hormones can influence both exocrine and endocrine blood vessels, and these complex effects are discussed. Secondary changes in pancreatic and islet blood flow occur during several conditions. To what extent changes in blood perfusion may affect the pathogenesis of pancreatic diseases is discussed. Both type 2 diabetes mellitus and acute pancreatitis are conditions where we think there is evidence that blood flow may contribute to disease manifestations. © 2019 American Physiological Society. Compr Physiol 9:799-837, 2019.
Collapse
Affiliation(s)
- Leif Jansson
- Uppsala University, Department of Medical Cell Biology, Uppsala, Sweden
| | - Per-Ola Carlsson
- Uppsala University, Department of Medical Cell Biology, Uppsala, Sweden.,Uppsala University, Department of Medical Sciences, Uppsala, Sweden
| |
Collapse
|
6
|
Abstract
PURPOSES OF REVIEW Scattered throughout the pancreas, the endocrine islets rely on neurovascular support for signal relay to regulate hormone secretion and for maintaining tissue homeostasis. The islet accessory cells (or components) of neurovascular tissues include the endothelial cells, pericytes, smooth muscle cells, neurons (nerve fibers), and glia. Research results derived from experimental diabetes and islet transplantation indicate that the accessory cells are reactive in islet injury and can affect islet function and homeostasis in situ or in an ectopic environment. RECENT FINDINGS Recent advances in cell labeling and tissue imaging have enabled investigation of islet accessory cells to gain insights into their network structures, functions, and remodeling in disease. It has become clear that in diabetes, the islet neurovascular tissues are not just bystanders damaged in neuropathy and vascular complications; rather, they participate in islet remodeling in response to changes in the microenvironment. Because of the fundamental differences between humans and animal models in neuroinsular cytoarchitecture and cell proliferation, examination of islet accessory cells in clinical specimens and donor pancreases warrants further attention.
Collapse
Affiliation(s)
- Shiue-Cheng Tang
- Department of Medical Science and Institute of Biotechnology, National Tsing Hua University, Hsinchu, 30013, Taiwan.
| | - Claire F Jessup
- College of Medicine and Public Health, Flinders University and Discipline of Medicine, University of Adelaide, Adelaide, SA, 5001, Australia.
| | - Martha Campbell-Thompson
- Department of Pathology, Immunology, and Laboratory Medicine, 1395 Center Drive, College of Medicine, University of Florida, Gainesville, FL, 32610, USA.
| |
Collapse
|
7
|
Cholinergic signaling mediates the effects of xenin-25 on secretion of pancreatic polypeptide but not insulin or glucagon in humans with impaired glucose tolerance. PLoS One 2018; 13:e0192441. [PMID: 29466430 PMCID: PMC5821323 DOI: 10.1371/journal.pone.0192441] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 01/10/2018] [Indexed: 01/14/2023] Open
Abstract
We previously demonstrated that infusion of an intestinal peptide called xenin-25 (Xen) amplifies the effects of glucose-dependent insulinotropic polypeptide (GIP) on insulin secretion rates (ISRs) and plasma glucagon levels in humans. However, these effects of Xen, but not GIP, were blunted in humans with type 2 diabetes. Thus, Xen rather than GIP signaling to islets fails early during development of type 2 diabetes. The current crossover study determines if cholinergic signaling relays the effects of Xen on insulin and glucagon release in humans as in mice. Fasted subjects with impaired glucose tolerance were studied. On eight separate occasions, each person underwent a single graded glucose infusion- two each with infusion of albumin, Xen, GIP, and GIP plus Xen. Each infusate was administered ± atropine. Heart rate and plasma glucose, insulin, C-peptide, glucagon, and pancreatic polypeptide (PP) levels were measured. ISRs were calculated from C-peptide levels. All peptides profoundly increased PP responses. From 0 to 40 min, peptide(s) infusions had little effect on plasma glucose concentrations. However, GIP, but not Xen, rapidly and transiently increased ISRs and glucagon levels. Both responses were further amplified when Xen was co-administered with GIP. From 40 to 240 min, glucose levels and ISRs continually increased while glucagon concentrations declined, regardless of infusate. Atropine increased resting heart rate and blocked all PP responses but did not affect ISRs or plasma glucagon levels during any of the peptide infusions. Thus, cholinergic signaling mediates the effects of Xen on insulin and glucagon release in mice but not humans.
Collapse
|
8
|
Lin PY, Peng SJ, Shen CN, Pasricha PJ, Tang SC. PanIN-associated pericyte, glial, and islet remodeling in mice revealed by 3D pancreatic duct lesion histology. Am J Physiol Gastrointest Liver Physiol 2016; 311:G412-22. [PMID: 27340125 PMCID: PMC6347070 DOI: 10.1152/ajpgi.00071.2016] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Accepted: 06/20/2016] [Indexed: 01/31/2023]
Abstract
Pericytes and glial cells are accessory cells of neurovascular networks, which have been reported to participate in scar formation after tissue injury. However, it remains unclear whether similar reactive cellular responses occur in pancreatic intraepithelial neoplasia (PanIN). In this study we developed three-dimensional (3D) duct lesion histology to investigate PanIN and the associated pericyte, glial, and islet remodeling. Transparent mouse pancreata with a Kras(G12D) mutation were used to develop 3D duct lesion histology. Deep-tissue, tile-scanning microscopy was performed to generate panoramic views of the diseased pancreas for global examination of early stage and advanced duct lesion formation. Fluorescence signals of ductal and neurovascular networks were simultaneously detected to reveal associated remodeling. Significantly, in Kras(G12D)-mutant mice, when the low-grade PanINs emerge, duct lesions appear as epithelial buds with perilesional pericyte and glial activation. When PanINs occur in large scale (induced by cerulein injections to the mutant mice), the 3D image data identifies 1) aggregation of PanINs in clusters in space; 2) overexpression of the pericyte marker NG2 in the PanIN microenvironment; and 3) epithelial in-growth to islets, forming the PanIN-islet complexes. Particularly, the PanIN-islet complexes associate with proliferating epithelial and stromal cells and receive substantial neurovascular supplies, making them landmarks in the atrophic lobe. Overall, perilesional pericyte and glial activation and formation of the PanIN-islet complex underline cellular heterogeneity in the duct lesion microenvironment. The results also illustrate the advantage of using 3D histology to reveal previously unknown details of neurovascular and endocrine links to the disease.
Collapse
Affiliation(s)
- Pei-Yu Lin
- 1Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan; ,2Genomics Research Center, Academia Sinica, Taipei, Taiwan;
| | - Shih-Jung Peng
- 3Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan; ,4Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan; and
| | - Chia-Ning Shen
- 1Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan; ,2Genomics Research Center, Academia Sinica, Taipei, Taiwan;
| | - Pankaj J. Pasricha
- 5Division of Gastroenterology and Hepatology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Shiue-Cheng Tang
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan; Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan; and
| |
Collapse
|
9
|
Chowdhury S, Wang S, Dunai J, Kilpatrick R, Oestricker LZ, Wallendorf MJ, Patterson BW, Reeds DN, Wice BM. Hormonal Responses to Cholinergic Input Are Different in Humans with and without Type 2 Diabetes Mellitus. PLoS One 2016; 11:e0156852. [PMID: 27304975 PMCID: PMC4909255 DOI: 10.1371/journal.pone.0156852] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 05/20/2016] [Indexed: 12/14/2022] Open
Abstract
Peripheral muscarinic acetylcholine receptors regulate insulin and glucagon release in rodents but their importance for similar roles in humans is unclear. Bethanechol, an acetylcholine analogue that does not cross the blood-brain barrier, was used to examine the role of peripheral muscarinic signaling on glucose homeostasis in humans with normal glucose tolerance (NGT; n = 10), impaired glucose tolerance (IGT; n = 11), and type 2 diabetes mellitus (T2DM; n = 9). Subjects received four liquid meal tolerance tests, each with a different dose of oral bethanechol (0, 50, 100, or 150 mg) given 60 min before a meal containing acetaminophen. Plasma pancreatic polypeptide (PP), glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide-1 (GLP-1), glucose, glucagon, C-peptide, and acetaminophen concentrations were measured. Insulin secretion rates (ISRs) were calculated from C-peptide levels. Acetaminophen and PP concentrations were surrogate markers for gastric emptying and cholinergic input to islets. The 150 mg dose of bethanechol increased the PP response 2-fold only in the IGT group, amplified GLP-1 release in the IGT and T2DM groups, and augmented the GIP response only in the NGT group. However, bethanechol did not alter ISRs or plasma glucose, glucagon, or acetaminophen concentrations in any group. Prior studies showed infusion of xenin-25, an intestinal peptide, delays gastric emptying and reduces GLP-1 release but not ISRs when normalized to plasma glucose levels. Analysis of archived plasma samples from this study showed xenin-25 amplified postprandial PP responses ~4-fold in subjects with NGT, IGT, and T2DM. Thus, increasing postprandial cholinergic input to islets augments insulin secretion in mice but not humans. Trial Registration: ClinicalTrials.gov NCT01434901
Collapse
Affiliation(s)
- Sara Chowdhury
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Lipid Research Washington University School of Medicine, Saint Louis, MO, United States of America
| | - Songyan Wang
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Lipid Research Washington University School of Medicine, Saint Louis, MO, United States of America
| | - Judit Dunai
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Lipid Research Washington University School of Medicine, Saint Louis, MO, United States of America
| | - Rachel Kilpatrick
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Lipid Research Washington University School of Medicine, Saint Louis, MO, United States of America
| | - Lauren Z. Oestricker
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Lipid Research Washington University School of Medicine, Saint Louis, MO, United States of America
| | - Michael J. Wallendorf
- Division of Biostatistics, Washington University School of Medicine, Saint Louis, MO, United States of America
| | - Bruce W. Patterson
- Department of Internal Medicine, Division of Nutritional Science, Metabolism and Lipid Research Washington University School of Medicine, Saint Louis, MO, United States of America
| | - Dominic N. Reeds
- Department of Internal Medicine, Division of Nutritional Science, Metabolism and Lipid Research Washington University School of Medicine, Saint Louis, MO, United States of America
| | - Burton M. Wice
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Lipid Research Washington University School of Medicine, Saint Louis, MO, United States of America
- * E-mail:
| |
Collapse
|
10
|
3-D imaging of islets in obesity: formation of the islet-duct complex and neurovascular remodeling in young hyperphagic mice. Int J Obes (Lond) 2015; 40:685-97. [PMID: 26499436 DOI: 10.1038/ijo.2015.224] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Revised: 09/15/2015] [Accepted: 10/10/2015] [Indexed: 01/30/2023]
Abstract
BACKGROUND Obesity and insulin resistance lead to islet hyperplasia. However, how the islet remodeling influences the pancreatic environment and the associated neurovascular networks is largely unknown. The lack of information is primarily due to the difficulty of global visualization of the hyperplasic islet (>200 μm) and the neurovascular environment with high definition. METHODS We modulated the pancreatic optical property to achieve 3-dimensional (3-D) whole-islet histology and to integrate transmitted light microscopy (which provides the ground-truth tissue information) with confocal fluorescence imaging. The new optical and imaging conditions were used to globally examine the hyperplastic islets of the young (2 months) obese db/db and ob/ob mice, which otherwise cannot be easily portrayed by the standard microtome-based histology. The voxel-based islet micrographs were digitally processed for stereo projection and qualitative and quantitative analyses of the islet tissue networks. RESULTS Paired staining and imaging of the pancreatic islets, ducts and neurovascular networks reveal the unexpected formation of the 'neuro-insular-ductal complex' in the young obese mice. The complex consists of the peri- and/or intra-islet ducts and prominent peri-ductal sympathetic nerves; the latter contributes to a marked increase in islet sympathetic innervation. In vascular characterization, we identify a decreased perivascular density of the ob/ob islet pericytes, which adapt to ensheathing the dilated microvessels with hypertrophic processes. CONCLUSIONS Modulation of pancreatic optical property enables 3-D panoramic examination of islets in the young hyperphagic mice to reveal the formation of the islet-duct complex and neurovascular remodeling. On the basis of the morphological proximity of the remodeled tissue networks, we propose a reactive islet microenvironment consisting of the endocrine cells, ductal epithelium and neurovascular tissues in response to the metabolic challenge that is experienced early in life.
Collapse
|
11
|
Lubaczeuski C, Balbo SL, Ribeiro RA, Vettorazzi JF, Santos-Silva JC, Carneiro EM, Bonfleur ML. Vagotomy ameliorates islet morphofunction and body metabolic homeostasis in MSG-obese rats. ACTA ACUST UNITED AC 2015; 48:447-57. [PMID: 25714886 PMCID: PMC4445669 DOI: 10.1590/1414-431x20144340] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Accepted: 11/17/2014] [Indexed: 01/11/2023]
Abstract
The parasympathetic nervous system is important for β-cell secretion and mass
regulation. Here, we characterized involvement of the vagus nerve in pancreatic
β-cell morphofunctional regulation and body nutrient homeostasis in 90-day-old
monosodium glutamate (MSG)-obese rats. Male newborn Wistar rats received MSG (4 g/kg
body weight) or saline [control (CTL) group] during the first 5 days of life. At 30
days of age, both groups of rats were submitted to sham-surgery (CTL and MSG groups)
or subdiaphragmatic vagotomy (Cvag and Mvag groups). The 90-day-old MSG rats
presented obesity, hyperinsulinemia, insulin resistance, and hypertriglyceridemia.
Their pancreatic islets hypersecreted insulin in response to glucose but did not
increase insulin release upon carbachol (Cch) stimulus, despite a higher
intracellular Ca2+ mobilization. Furthermore, while the pancreas weight
was 34% lower in MSG rats, no alteration in islet and β-cell mass was observed.
However, in the MSG pancreas, increases of 51% and 55% were observed in the total
islet and β-cell area/pancreas section, respectively. Also, the β-cell number per
β-cell area was 19% higher in MSG rat pancreas than in CTL pancreas. Vagotomy
prevented obesity, reducing 25% of body fat stores and ameliorated glucose
homeostasis in Mvag rats. Mvag islets demonstrated partially reduced insulin
secretion in response to 11.1 mM glucose and presented normalization of Cch-induced
Ca2+ mobilization and insulin release. All morphometric parameters were
similar among Mvag and CTL rat pancreases. Therefore, the higher insulin release in
MSG rats was associated with greater β-cell/islet numbers and not due to hypertrophy.
Vagotomy improved whole body nutrient homeostasis and endocrine pancreatic
morphofunction in Mvag rats.
Collapse
Affiliation(s)
- C Lubaczeuski
- Laboratório de Fisiologia Endócrina e Metabolismo, Centro de Ciências Biológicas e da Saúde, Universidade Estadual do Oeste do Paraná, Cascavel, PR, Brasil
| | - S L Balbo
- Laboratório de Fisiologia Endócrina e Metabolismo, Centro de Ciências Biológicas e da Saúde, Universidade Estadual do Oeste do Paraná, Cascavel, PR, Brasil
| | - R A Ribeiro
- Universidade Federal do Rio de Janeiro, Macaé, RJ, Brasil
| | - J F Vettorazzi
- Departamento de Biologia Estrutural e Funcional, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brasil
| | - J C Santos-Silva
- Departamento de Biologia Estrutural e Funcional, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brasil
| | - E M Carneiro
- Departamento de Biologia Estrutural e Funcional, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brasil
| | - M L Bonfleur
- Laboratório de Fisiologia Endócrina e Metabolismo, Centro de Ciências Biológicas e da Saúde, Universidade Estadual do Oeste do Paraná, Cascavel, PR, Brasil
| |
Collapse
|
12
|
Juang JH, Kuo CH, Peng SJ, Tang SC. 3-D Imaging Reveals Participation of Donor Islet Schwann Cells and Pericytes in Islet Transplantation and Graft Neurovascular Regeneration. EBioMedicine 2015; 2:109-19. [PMID: 26137552 PMCID: PMC4485478 DOI: 10.1016/j.ebiom.2015.01.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 01/25/2015] [Accepted: 01/25/2015] [Indexed: 01/26/2023] Open
Abstract
The primary cells that participate in islet transplantation are the endocrine cells. However, in the islet microenvironment, the endocrine cells are closely associated with the neurovascular tissues consisting of the Schwann cells and pericytes, which form sheaths/barriers at the islet exterior and interior borders. The two cell types have shown their plasticity in islet injury, but their roles in transplantation remain unclear. In this research, we applied 3-dimensional neurovascular histology with cell tracing to reveal the participation of Schwann cells and pericytes in mouse islet transplantation. Longitudinal studies of the grafts under the kidney capsule identify that the donor Schwann cells and pericytes re-associate with the engrafted islets at the peri-graft and perivascular domains, respectively, indicating their adaptability in transplantation. Based on the morphological proximity and cellular reactivity, we propose that the new islet microenvironment should include the peri-graft Schwann cell sheath and perivascular pericytes as an integral part of the new tissue. 3-D neurovascular histology with cell tracing is used to study islet transplantation. Donor islet Schwann cells and pericytes participate in graft neurovascular regeneration. Islet graft microenvironment includes Schwann cell sheath and perivascular pericytes.
Collapse
Affiliation(s)
- Jyuhn-Huarng Juang
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Chang Gung Memorial Hospital, Taoyuan 33302, Taiwan ; Department of Medicine, College of Medicine, Chang Gung University, Taoyuan 33302, Taiwan
| | - Chien-Hung Kuo
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Chang Gung Memorial Hospital, Taoyuan 33302, Taiwan ; Biomedical Technology and Device Research Laboratories, Industrial Technology Research Institute, Hsinchu 31040, Taiwan
| | - Shih-Jung Peng
- Connectomics Research Center, National Tsing Hua University, Hsinchu 30013, Taiwan ; Institute of Biotechnology, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Shiue-Cheng Tang
- Connectomics Research Center, National Tsing Hua University, Hsinchu 30013, Taiwan ; Institute of Biotechnology, National Tsing Hua University, Hsinchu 30013, Taiwan ; Department of Medical Science, National Tsing Hua University, Hsinchu 30013, Taiwan
| |
Collapse
|
13
|
Tang SC, Peng SJ, Chien HJ. Imaging of the islet neural network. Diabetes Obes Metab 2014; 16 Suppl 1:77-86. [PMID: 25200300 DOI: 10.1111/dom.12342] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Accepted: 05/28/2014] [Indexed: 02/06/2023]
Abstract
The islets of Langerhans receive signals from the circulation and nerves to modulate hormone secretion in response to physiological cues. Although the rich islet innervation has been documented in the literature dating as far back as Paul Langerhans' discovery of islets in the pancreas, it remains a challenging task for researchers to acquire detailed islet innervation patterns in health and disease due to the dispersed nature of the islet neurovascular network. In this article, we discuss the recent development of 3-dimensional (3D) islet neurohistology, in which transparent pancreatic specimens were prepared by optical clearing to visualize the islet microstructure, vasculature and innervation with deep-tissue microscopy. Mouse islets were used as an example to illustrate how to apply this 3D imaging approach to characterize (i) the islet parasympathetic innervation, (ii) the islet sympathetic innervation and its reinnervation after transplantation under the kidney capsule and (iii) the reactive cellular response of the Schwann cell network in islet injury. While presenting and characterizing the innervation patterns, we also discuss how to apply the signals derived from transmitted light microscopy, vessel painting and immunostaining of neural markers to verify the location and source of tissue information. In summary, the systematic development of tissue labelling, clearing and imaging methods to reveal the islet neuroanatomy offers insights to help study the neural-islet regulatory mechanisms and the role of neural tissue remodelling in the development of diabetes.
Collapse
Affiliation(s)
- S-C Tang
- Connectomics Research Center, National Tsing Hua University, Hsinchu, Taiwan; Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan; Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan
| | | | | |
Collapse
|
14
|
Nunemaker CS, Satin LS. Episodic hormone secretion: a comparison of the basis of pulsatile secretion of insulin and GnRH. Endocrine 2014; 47:49-63. [PMID: 24610206 PMCID: PMC4382805 DOI: 10.1007/s12020-014-0212-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2014] [Accepted: 02/13/2014] [Indexed: 01/01/2023]
Abstract
Rhythms govern many endocrine functions. Examples of such rhythmic systems include the insulin-secreting pancreatic beta-cell, which regulates blood glucose, and the gonadotropin-releasing hormone (GnRH) neuron, which governs reproductive function. Although serving very different functions within the body, these cell types share many important features. Both GnRH neurons and beta-cells, for instance, are hypothesized to generate at least two rhythms endogenously: (1) a burst firing electrical rhythm and (2) a slower rhythm involving metabolic or other intracellular processes. This review discusses the importance of hormone rhythms to both physiology and disease and compares and contrasts the rhythms generated by each system.
Collapse
Affiliation(s)
- Craig S. Nunemaker
- Division of Endocrinology and Metabolism, Department of, Medicine, University of Virginia, P.O. Box 801413, Charlottesville, VA 22901, USA,
| | - Leslie S. Satin
- Pharmacology Department, University of Michigan Medical School, 5128 Brehm Tower, Ann Arbor, MI 48105, USA
- Brehm Diabetes Research Center, University of Michigan, Medical School, 5128 Brehm Tower, Ann Arbor, MI 48105, USA
| |
Collapse
|
15
|
Juang JH, Peng SJ, Kuo CH, Tang SC. Three-dimensional islet graft histology: panoramic imaging of neural plasticity in sympathetic reinnervation of transplanted islets under the kidney capsule. Am J Physiol Endocrinol Metab 2014; 306:E559-70. [PMID: 24425762 DOI: 10.1152/ajpendo.00515.2013] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Microscopic examination of transplanted islets in an ectopic environment provides information to evaluate islet engraftment, including revascularization and reinnervation. However, because of the dispersed nature of blood vessels and nerves, global visualization of the graft neurovascular network has been difficult. In this research we revealed the neurovascular network by preparing transparent mouse islet grafts under the kidney capsule with optical clearing to investigate the sympathetic reinnervation via three-dimensional confocal microscopy. Normoglycemic and streptozotocin-induced diabetic mice were used in syngeneic islet transplantation, with both groups maintaining euglycemia after transplantation. Triple staining of insulin/glucagon, blood vessels, and tyrosine hydroxylase (sympathetic marker) was used to reveal the graft microstructure, vasculature, and sympathetic innervation. Three weeks after transplantation, we observed perigraft sympathetic innervation similar to the peri-islet sympathetic innervation in the pancreas. Six weeks after transplantation, prominent intragraft, perivascular sympathetic innervation was achieved, resembling the pancreatic intraislet, perivascular sympathetic innervation in situ. Meanwhile, in diabetic recipients, a higher graft sympathetic nerve density was found compared with grafts in normoglycemic recipients, indicating the graft neural plasticity in response to the physiological difference of the recipients and the resolving power of this imaging approach. Overall, this new graft imaging method provides a useful tool to identify the islet neurovascular complex in an ectopic environment to study islet engraftment.
Collapse
Affiliation(s)
- Jyuhn-Huarng Juang
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | | | | | | |
Collapse
|
16
|
Ho MM, Hu X, Karunakaran S, Johnson JD, Clee SM. Altered pancreatic growth and insulin secretion in WSB/EiJ mice. PLoS One 2014; 9:e88352. [PMID: 24505481 PMCID: PMC3914989 DOI: 10.1371/journal.pone.0088352] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2013] [Accepted: 01/07/2014] [Indexed: 01/03/2023] Open
Abstract
These data suggest that insulin secretion in WSB mice is blunted specifically in vivo, either due to a reduced insulin requirement and/or due to factors that are absent or destroyed in vitro. These studies also highlight the role of post-natal growth in determining adult β-cell mass. Mice are important animal models for the study of metabolic physiology and the genetics of complex traits. Wild-derived inbred mouse strains, such as WSB/EiJ (WSB), are unrelated to the commonly studied mouse strains and are valuable tools to identify novel genes that modify disease risk. We have previously shown that in contrast to C57BL/6J (B6) mice, WSB mice fed a high fat diet do not develop hyperinsulinemia or insulin resistance, and had nearly undetectable insulin secretion in response to an intraperitoneal glucose challenge. As hyperinsulinemia may drive obesity and insulin resistance, we examined whether defects in β-cell mass or function could contribute to the low insulin levels in WSB mice. In young WSB mice, β-cell mass was similar to B6 mice. However, we found that adult WSB mice had reduced β-cell mass due to reduced pancreatic weights. Pancreatic sizes were similar between the strains when normalized to body weight, suggesting their pancreatic size is appropriate to their body size in adults, but overall post-natal pancreatic growth was reduced in WSB mice compared to B6 mice. Islet architecture was normal in WSB mice. WSB mice had markedly increased insulin secretion from isolated islets in vitro. These data suggest that insulin secretion in WSB mice is blunted specifically in vivo, either due to a reduced insulin requirement and/or due to factors that are absent or destroyed in vitro. These studies suggest that WSB mice may provide novel insight into mechanisms regulating insulin secretion and also highlight the role of post-natal growth in determining adult β-cell mass.
Collapse
Affiliation(s)
- Maggie M. Ho
- Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Xiaoke Hu
- Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Subashini Karunakaran
- Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - James D. Johnson
- Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Surgery, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Susanne M. Clee
- Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
- * E-mail:
| |
Collapse
|
17
|
Hiriart M, Velasco M, Larqué C, Diaz-Garcia CM. Metabolic Syndrome and Ionic Channels in Pancreatic Beta Cells. THE PANCREATIC BETA CELL 2014; 95:87-114. [DOI: 10.1016/b978-0-12-800174-5.00004-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
|
18
|
Tang SC, Chiu YC, Hsu CT, Peng SJ, Fu YY. Plasticity of Schwann cells and pericytes in response to islet injury in mice. Diabetologia 2013; 56:2424-34. [PMID: 23801221 DOI: 10.1007/s00125-013-2977-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Accepted: 06/11/2013] [Indexed: 01/28/2023]
Abstract
AIMS/HYPOTHESIS Islet Schwann (glial) cells and pericytes are the microorgan's accessory cells positioned at the external and internal boundaries facing the exocrine pancreas and endothelium, respectively, adjacent to the endocrine cells. Plasticity of glial cells and pericytes is shown in the glial scar formation after injury to the central nervous system. It remains unclear whether similar reactive cellular responses occur in insulitis. We applied three-dimensional (3D) histology to perform qualitative and quantitative analyses of the islet Schwann cell network and pericytes in normal, streptozotocin-injected (positive control of gliosis) and NOD mouse models. METHODS Vessel painting paired with immunostaining of mouse pancreatic tissue was used to reveal the islet Schwann cells and pericytes and their association with vasculature. Transparent islet specimens were prepared by optical clearing to facilitate 3D confocal microscopy for panoramic visualisation of the tissue networks. RESULTS In-depth microscopy showed that the islet Schwann cell network extends from the peri-islet domain into the core. One week after streptozotocin injection, we observed intra-islet perivascular gliosis and an increase in pericyte density. In early/moderate insulitis in the NOD mice, perilesional gliosis occurred at the front of the lymphocytic infiltration with atypical islet Schwann cell morphologies, including excessive branching and perivascular gliosis. Meanwhile, pericytes aggregated on the walls of the feeding arteriole at the peri- and intralesional domains with a marked increase in surface marker density. CONCLUSIONS/INTERPRETATION The reactive cellular responses demonstrate plasticity and suggest a stop-gap mechanism consisting of the Schwann cells and pericytes in association with the islet lesion and vasculature when injury occurs.
Collapse
Affiliation(s)
- Shiue-Cheng Tang
- Connectomics Research Center, National Tsing Hua University, Hsinchu, Taiwan,
| | | | | | | | | |
Collapse
|