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Johansen CG, Holcomb K, Sela A, Morrall S, Park D, Farnsworth NL. Extracellular matrix stiffness mediates insulin secretion in pancreatic islets via mechanosensitive Piezo1 channel regulated Ca 2+ dynamics. Matrix Biol Plus 2024; 22:100148. [PMID: 38803329 PMCID: PMC11128509 DOI: 10.1016/j.mbplus.2024.100148] [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: 12/30/2023] [Revised: 05/08/2024] [Accepted: 05/09/2024] [Indexed: 05/29/2024] Open
Abstract
The pancreatic islet is surrounded by ECM that provides both biochemical and mechanical cues to the islet β-cell to regulate cell survival and insulin secretion. Changes in ECM composition and mechanical properties drive β-cell dysfunction in many pancreatic diseases. While several studies have characterized changes in islet insulin secretion with changes in substrate stiffness, little is known about the mechanotransduction signaling driving altered islet function in response to mechanical cues. We hypothesized that increasing matrix stiffness will lead to insulin secretion dysfunction by opening the mechanosensitive ion channel Piezo1 and disrupting intracellular Ca2+ dynamics in mouse and human islets. To test our hypothesis, mouse and human cadaveric islets were encapsulated in a biomimetic reverse thermal gel (RTG) scaffold with tailorable stiffness that allows formation of islet focal adhesions with the scaffold and activation of Piezo1 in 3D. Our results indicate that increased scaffold stiffness causes insulin secretion dysfunction mediated by increases in Ca2+ influx and altered Ca2+ dynamics via opening of the mechanosensitive Piezo1 channel. Additionally, inhibition of Piezo1 rescued glucose-stimulated insulin secretion (GSIS) in islets in stiff scaffolds. Overall, our results emphasize the role mechanical properties of the islet microenvironment plays in regulating function. It also supports further investigation into the modulation of Piezo1 channel activity to restore islet function in diseases like type 2 diabetes (T2D) and pancreatic cancer where fibrosis of the peri-islet ECM leads to increased tissue stiffness and islet dysfunction.
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Affiliation(s)
- Chelsea G Johansen
- Department of Chemical & Biological Engineering, Colorado School of Mines, Golden, CO 80401, USA
| | - Keifer Holcomb
- Department of Chemical & Biological Engineering, Colorado School of Mines, Golden, CO 80401, USA
| | - Amit Sela
- Quantitative Biosciences & Engineering, Colorado School of Mines, Golden, CO 80401, USA
| | - Stephanie Morrall
- Quantitative Biosciences & Engineering, Colorado School of Mines, Golden, CO 80401, USA
| | - Daewon Park
- Department of Bioengineering, University of Colorado Denver Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Nikki L Farnsworth
- Department of Chemical & Biological Engineering, Colorado School of Mines, Golden, CO 80401, USA
- Quantitative Biosciences & Engineering, Colorado School of Mines, Golden, CO 80401, USA
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Ye J, Guo K, Li J, Li X, Zhou Z, Yang L. Estimating the effect of lipid-lowering agents on novel subtypes of adult-onset diabetes. Diabetes Metab Res Rev 2024; 40:e3793. [PMID: 38661109 DOI: 10.1002/dmrr.3793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 01/30/2024] [Accepted: 03/05/2024] [Indexed: 04/26/2024]
Abstract
AIMS The aims of the present study were to assess the effects of lipid-lowering drugs [HMG-CoA reductase inhibitors, proprotein convertase subtilisin/kexin type 9 inhibitors, and Niemann-Pick C1-Like 1 (NPC1L1) inhibitors] on novel subtypes of adult-onset diabetes through a Mendelian randomisation study. MATERIALS AND METHODS We first inferred causal associations between lipid-related traits [including high-density lipoprotein cholesterol, low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), apolipoproteins A-I, and apolipoproteins B] and novel subtypes of adult-onset diabetes. The expression quantitative trait loci of drug target genes for three classes of lipid-lowering drugs, as well as genetic variants within or nearby drug target genes associated with LDL-C, were then utilised as proxies for the exposure of lipid-lowering drugs. Mendelian randomisation analysis was performed using summary data from genome-wide association studies of LDL-C, severe autoimmune diabetes, severe insulin-deficient diabetes (SIDD), severe insulin-resistant diabetes (SIRD), mild obesity-related diabetes (MOD), and mild age-related diabetes. RESULTS There was an association between HMGCR-mediated LDL-C and the risk of SIRD [odds ratio (OR) = 0.305, 95% confidence interval (CI) = 0.129-0.723; p = 0.007], and there was an association of PCSK9-mediated LDL-C with the risk of SIDD (OR = 0.253, 95% CI = 0.120-0.532; p < 0.001) and MOD (OR = 0.345, 95% CI = 0.171-0.696; p = 0.003). Moreover, NPC1L1-mediated LDL-C (OR = 0.109, 95% CI = 0.019-0.613; p = 0.012) and the increased expression of NPC1L1 gene in blood (OR = 0.727, 95% CI = 0.541-0.977; p = 0.034) both showed a significant association with SIRD. These results were further confirmed by sensitivity analyses. CONCLUSIONS In summary, the different lipid-lowering medications have a specific effect on the increased risk of different novel subtypes of adult-onset diabetes.
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Affiliation(s)
- Jianan Ye
- National Clinical Research Center for Metabolic Diseases, Key Laboratory of Diabetes Immunology (Central South University), Ministry of Education, and Department of Metabolism and Endocrinology, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Keyu Guo
- National Clinical Research Center for Metabolic Diseases, Key Laboratory of Diabetes Immunology (Central South University), Ministry of Education, and Department of Metabolism and Endocrinology, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Jiaqi Li
- National Clinical Research Center for Metabolic Diseases, Key Laboratory of Diabetes Immunology (Central South University), Ministry of Education, and Department of Metabolism and Endocrinology, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Xia Li
- National Clinical Research Center for Metabolic Diseases, Key Laboratory of Diabetes Immunology (Central South University), Ministry of Education, and Department of Metabolism and Endocrinology, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Zhiguang Zhou
- National Clinical Research Center for Metabolic Diseases, Key Laboratory of Diabetes Immunology (Central South University), Ministry of Education, and Department of Metabolism and Endocrinology, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Lin Yang
- National Clinical Research Center for Metabolic Diseases, Key Laboratory of Diabetes Immunology (Central South University), Ministry of Education, and Department of Metabolism and Endocrinology, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
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3
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Schilling K, Chen H, Glabonjat RA, Debernardi S, Blyuss O, Navas-Acien A, Halliday AN, Crnogorac-Jurcevic T. Analysis of urinary potassium isotopes and association with pancreatic health: healthy, diabetic and cancerous states. Front Endocrinol (Lausanne) 2024; 15:1332895. [PMID: 38694937 PMCID: PMC11062322 DOI: 10.3389/fendo.2024.1332895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Accepted: 03/01/2024] [Indexed: 05/04/2024] Open
Abstract
Background More than 700 million people worldwide suffer from diseases of the pancreas, such as diabetes, pancreatitis and pancreatic cancer. Often dysregulation of potassium (K+) channels, co-transporters and pumps can promote development and progression of many types of these diseases. The role of K+ transport system in pancreatic cell homeostasis and disease development remains largely unexplored. Potassium isotope analysis (δ41K), however, might have the potential to detect minute changes in metabolic processes relevant for pancreatic diseases. Methods We assessed urinary K isotope composition in a case-control study by measuring K concentrations and δ41K in spot urines collected from patients diagnosed with pancreatic cancer (n=18), other pancreas-related diseases (n=14) and compared those data to healthy controls (n=16). Results Our results show that urinary K+ levels for patients with diseased pancreas (benign and pancreatic cancer) are significantly lower than the healthy controls. For δ41K, the values tend to be higher for individuals with pancreatic cancer (mean δ41K = -0.58 ± 0.33‰) than for healthy individuals (mean δ41K = -0.78 ± 0.19‰) but the difference is not significant (p=0.08). For diabetics, urinary K+ levels are significantly lower (p=0.03) and δ41K is significantly higher (p=0.009) than for the healthy controls. These results suggest that urinary K+ levels and K isotopes can help identify K disturbances related to diabetes, an associated factors of all-cause mortality for diabetics. Conclusion Although the K isotope results should be considered exploratory and hypothesis-generating and future studies should focus on larger sample size and δ41K analysis of other K-disrupting diseases (e.g., chronic kidney disease), our data hold great promise for K isotopes as disease marker.
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Affiliation(s)
- Kathrin Schilling
- Department of Environmental Health Sciences, Columbia University Mailman School of Public Health, New York, NY, United States
- Lamont‐Doherty Earth Observatory, Columbia University, Palisades, NY, United States
| | - Heng Chen
- Lamont‐Doherty Earth Observatory, Columbia University, Palisades, NY, United States
| | - Ronald A. Glabonjat
- Department of Environmental Health Sciences, Columbia University Mailman School of Public Health, New York, NY, United States
| | - Silvana Debernardi
- Centre for Cancer Biomarkers and Biotherapeutics, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Oleg Blyuss
- Wolfson’s Institute for Cancer Prevention, Queen Mary University of London, London, United Kingdom
| | - Ana Navas-Acien
- Department of Environmental Health Sciences, Columbia University Mailman School of Public Health, New York, NY, United States
| | - Alex N. Halliday
- Lamont‐Doherty Earth Observatory, Columbia University, Palisades, NY, United States
| | - Tatjana Crnogorac-Jurcevic
- Centre for Cancer Biomarkers and Biotherapeutics, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
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4
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Huang W, O'Hara SE, Xie C, Liu N, Rayner CK, Nicholas LM, Wu T. Effects of a bitter substance, denatonium benzoate, on pancreatic hormone secretion. Am J Physiol Endocrinol Metab 2024; 326:E537-E544. [PMID: 38477876 DOI: 10.1152/ajpendo.00046.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 03/06/2024] [Accepted: 03/06/2024] [Indexed: 03/14/2024]
Abstract
There is increasing evidence linking bitter taste receptor (BTR) signaling to gut hormone secretion and glucose homeostasis. However, its effect on islet hormone secretion has been poorly characterized. This study investigated the effect of the bitter substance, denatonium benzoate (DB), on hormone secretion from mouse pancreatic islets and INS-1 832/13 cells. DB (0.5-1 mM) augmented insulin secretion at both 2.8 mM and 16.7 mM glucose. This effect was no longer present at 5 mM DB likely due to the greater levels of cellular apoptosis. DB-stimulated insulin secretion involved closure of the KATP channel, activation of T2R signaling in beta-cells, and intraislet glucagon-like peptide-1 (GLP-1) release. DB also enhanced glucagon and somatostatin secretion, but the underlying mechanism was less clear. Together, this study demonstrates that the bitter substance, DB, is a strong potentiator of islet hormone secretion independent of glucose. This observation highlights the potential for widespread off-target effects associated with the clinical use of bitter-tasting substances.NEW & NOTEWORTHY We show that the bitter substance, denatonium benzoate (DB), stimulates insulin, glucagon, somatostatin, and GLP-1 secretion from pancreatic islets, independent of glucose, and that DB augments insulin release via the KATP channel, bitter taste receptor signaling, and intraislet GLP-1 secretion. Exposure to a high dose of DB (5 mM) induces cellular apoptosis in pancreatic islets. Therefore, clinical use of bitter substances to improve glucose homeostasis may have unintended negative impacts beyond the gut.
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Affiliation(s)
- Weikun Huang
- Centre for Research Excellence in Translating Nutritional Sciences to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide, South Australia, Australia
- Institute for Photonics and Advanced Sensing, School of Physics, Chemistry and Earth Sciences, The University of Adelaide, Adelaide, South Australia, Australia
| | - Stephanie E O'Hara
- Robinson Research Institute, The University of Adelaide, Adelaide, South Australia, Australia
- Adelaide Centre for Epigenetics, School of Biomedicine, The University of Adelaide, Adelaide, South Australia, Australia
| | - Cong Xie
- Centre for Research Excellence in Translating Nutritional Sciences to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide, South Australia, Australia
| | - Ning Liu
- Bioinformatics Division, The Walter and Eliza Hall Institute, Melbourne, Victoria, Australia
| | - Christopher K Rayner
- Centre for Research Excellence in Translating Nutritional Sciences to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide, South Australia, Australia
| | - Lisa M Nicholas
- Robinson Research Institute, The University of Adelaide, Adelaide, South Australia, Australia
- Adelaide Centre for Epigenetics, School of Biomedicine, The University of Adelaide, Adelaide, South Australia, Australia
| | - Tongzhi Wu
- Centre for Research Excellence in Translating Nutritional Sciences to Good Health, Adelaide Medical School, The University of Adelaide, Adelaide, South Australia, Australia
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5
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Alsup AM, Fowlds K, Cho M, Luber JM. BetaBuddy: An automated end-to-end computer vision pipeline for analysis of calcium fluorescence dynamics in β-cells. PLoS One 2024; 19:e0299549. [PMID: 38489336 PMCID: PMC10942061 DOI: 10.1371/journal.pone.0299549] [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: 04/10/2023] [Accepted: 02/12/2024] [Indexed: 03/17/2024] Open
Abstract
Insulin secretion from pancreatic β-cells is integral in maintaining the delicate equilibrium of blood glucose levels. Calcium is known to be a key regulator and triggers the release of insulin. This sub-cellular process can be monitored and tracked through live-cell imaging and subsequent cell segmentation, registration, tracking, and analysis of the calcium level in each cell. Current methods of analysis typically require the manual outlining of β-cells, involve multiple software packages, and necessitate multiple researchers-all of which tend to introduce biases. Utilizing deep learning algorithms, we have therefore created a pipeline to automatically segment and track thousands of cells, which greatly reduces the time required to gather and analyze a large number of sub-cellular images and improve accuracy. Tracking cells over a time-series image stack also allows researchers to isolate specific calcium spiking patterns and spatially identify those of interest, creating an efficient and user-friendly analysis tool. Using our automated pipeline, a previous dataset used to evaluate changes in calcium spiking activity in β-cells post-electric field stimulation was reanalyzed. Changes in spiking activity were found to be underestimated previously with manual segmentation. Moreover, the machine learning pipeline provides a powerful and rapid computational approach to examine, for example, how calcium signaling is regulated by intracellular interactions.
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Affiliation(s)
- Anne M. Alsup
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, United States of America
| | - Kelli Fowlds
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, United States of America
| | - Michael Cho
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, United States of America
| | - Jacob M. Luber
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, United States of America
- Department of Computer Science and Engineering, University of Texas at Arlington, Arlington, TX, United States of America
- Multi-Interprofessional Center for Health Informatics, University of Texas at Arlington, Arlington, TX, United States of America
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6
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Jacobo-Piqueras N, Theiner T, Geisler SM, Tuluc P. Molecular mechanism responsible for sex differences in electrical activity of mouse pancreatic β cells. JCI Insight 2024; 9:e171609. [PMID: 38358819 PMCID: PMC11063940 DOI: 10.1172/jci.insight.171609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 02/08/2024] [Indexed: 02/17/2024] Open
Abstract
In humans, type 2 diabetes mellitus shows a higher prevalence in men compared with women, a phenotype that has been attributed to a lower peripheral insulin sensitivity in men. Whether sex-specific differences in pancreatic β cell function also contribute is largely unknown. Here, we characterized the electrophysiological properties of β cells in intact male and female mouse islets. Elevation of glucose concentration above 5 mM triggered an electrical activity with a similar glucose dependence in β cells of both sexes. However, female β cells had a more depolarized membrane potential and increased firing frequency compared with males. The higher membrane depolarization in female β cells was caused by approximately 50% smaller Kv2.1 K+ currents compared with males but otherwise unchanged KATP, large-conductance and small-conductance Ca2+-activated K+ channels, and background TASK1/TALK1 K+ current densities. In female β cells, the higher depolarization caused a membrane potential-dependent inactivation of the voltage-gated Ca2+ channels (CaV), resulting in reduced Ca2+ entry. Nevertheless, this reduced Ca2+ influx was offset by a higher action potential firing frequency. Because exocytosis of insulin granules does not show a sex-specific difference, we conclude that the higher electrical activity promotes insulin release in females, improving glucose tolerance.
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7
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Rivera Nieves AM, Wauford BM, Fu A. Mitochondrial bioenergetics, metabolism, and beyond in pancreatic β-cells and diabetes. Front Mol Biosci 2024; 11:1354199. [PMID: 38404962 PMCID: PMC10884328 DOI: 10.3389/fmolb.2024.1354199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Accepted: 01/17/2024] [Indexed: 02/27/2024] Open
Abstract
In Type 1 and Type 2 diabetes, pancreatic β-cell survival and function are impaired. Additional etiologies of diabetes include dysfunction in insulin-sensing hepatic, muscle, and adipose tissues as well as immune cells. An important determinant of metabolic health across these various tissues is mitochondria function and structure. This review focuses on the role of mitochondria in diabetes pathogenesis, with a specific emphasis on pancreatic β-cells. These dynamic organelles are obligate for β-cell survival, function, replication, insulin production, and control over insulin release. Therefore, it is not surprising that mitochondria are severely defective in diabetic contexts. Mitochondrial dysfunction poses challenges to assess in cause-effect studies, prompting us to assemble and deliberate the evidence for mitochondria dysfunction as a cause or consequence of diabetes. Understanding the precise molecular mechanisms underlying mitochondrial dysfunction in diabetes and identifying therapeutic strategies to restore mitochondrial homeostasis and enhance β-cell function are active and expanding areas of research. In summary, this review examines the multidimensional role of mitochondria in diabetes, focusing on pancreatic β-cells and highlighting the significance of mitochondrial metabolism, bioenergetics, calcium, dynamics, and mitophagy in the pathophysiology of diabetes. We describe the effects of diabetes-related gluco/lipotoxic, oxidative and inflammation stress on β-cell mitochondria, as well as the role played by mitochondria on the pathologic outcomes of these stress paradigms. By examining these aspects, we provide updated insights and highlight areas where further research is required for a deeper molecular understanding of the role of mitochondria in β-cells and diabetes.
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Affiliation(s)
- Alejandra María Rivera Nieves
- Diabetes Center of Excellence, University of Massachusetts Chan Medical School, Worcester, MA, United States
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Brian Michael Wauford
- Diabetes Center of Excellence, University of Massachusetts Chan Medical School, Worcester, MA, United States
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Accalia Fu
- Diabetes Center of Excellence, University of Massachusetts Chan Medical School, Worcester, MA, United States
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, United States
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8
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Wang S, Aljirafi FO, Payne GF, Bentley WE. Excite the unexcitable: engineering cells and redox signaling for targeted bioelectronic control. Curr Opin Biotechnol 2024; 85:103052. [PMID: 38150921 DOI: 10.1016/j.copbio.2023.103052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 11/17/2023] [Accepted: 11/28/2023] [Indexed: 12/29/2023]
Abstract
The ever-growing influence of technology in our lives has led to an increasing interest in the development of smart electronic devices to interrogate and control biological systems. Recently, redox-mediated electrogenetics introduced a novel avenue that enables direct bioelectronic control at the genetic level. In this review, we discuss recent advances in methodologies for bioelectronic control, ranging from electrical stimulation to engineering efforts that allow traditionally unexcitable cells to be electrically 'programmable.' Alongside ion-transport signaling, we suggest redox as a route for rational engineering because it is a native form of electronic communication in biology. Using redox as a common language allows the interfacing of electronics and biology. This newfound connection opens a gateway of possibilities for next-generation bioelectronic tools.
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Affiliation(s)
- Sally Wang
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, USA; Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD, USA; Fischell Institute of Biomedical Devices, University of Maryland, College Park, MD, USA
| | - Futoon O Aljirafi
- Fischell Institute of Biomedical Devices, University of Maryland, College Park, MD, USA; Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD, USA
| | - Gregory F Payne
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD, USA; Fischell Institute of Biomedical Devices, University of Maryland, College Park, MD, USA
| | - William E Bentley
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, USA; Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD, USA; Fischell Institute of Biomedical Devices, University of Maryland, College Park, MD, USA
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9
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Bisht S, Singh MF. The triggering pathway, the metabolic amplifying pathway, and cellular transduction in regulation of glucose-dependent biphasic insulin secretion. Arch Physiol Biochem 2024:1-12. [PMID: 38196246 DOI: 10.1080/13813455.2023.2299920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 12/16/2023] [Indexed: 01/11/2024]
Abstract
Introduction: Insulin secretion is a highly regulated process critical for maintaining glucose homeostasis. This abstract explores the intricate interplay between three essential pathways: The Triggering Pathway, The Metabolic Amplifying Pathway, and Cellular Transduction, in orchestrating glucose-dependent biphasic insulin secretion.Mechanism: During the triggering pathway, glucose metabolism in pancreatic beta-cells leads to ATP production, closing ATP-sensitive potassium channels and initiating insulin exocytosis. The metabolic amplifying pathway enhances insulin secretion via key metabolites like NADH and glutamate, enhancing calcium influx and insulin granule exocytosis. Additionally, the cellular transduction pathway involves G-protein coupled receptors and cyclic AMP, modulating insulin secretion.Result and Conclusion: These interconnected pathways ensure a dynamic insulin response to fluctuating glucose levels, with the initial rapid phase and the subsequent sustained phase. Understanding these pathways' complexities provides crucial insights into insulin dysregulation in diabetes and highlights potential therapeutic targets to restore glucose-dependent insulin secretion.
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Affiliation(s)
- Shradha Bisht
- Amity Institute of Pharmacy, Amity University, Lucknow, Uttar Pradesh, India
| | - Mamta F Singh
- School of Pharmaceutical Sciences, SBS University, Balawala, Uttarakhand, India
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10
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Liu H, Irobalieva RN, Kowal J, Ni D, Nosol K, Bang-Sørensen R, Lancien L, Stahlberg H, Stieger B, Locher KP. Structural basis of bile salt extrusion and small-molecule inhibition in human BSEP. Nat Commun 2023; 14:7296. [PMID: 37949847 PMCID: PMC10638440 DOI: 10.1038/s41467-023-43109-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 10/31/2023] [Indexed: 11/12/2023] Open
Abstract
BSEP (ABCB11) is an ATP-binding cassette transporter that is expressed in hepatocytes and extrudes bile salts into the canaliculi of the liver. BSEP dysfunction, caused by mutations or induced by drugs, is frequently associated with severe cholestatic liver disease. We report the cryo-EM structure of glibenclamide-bound human BSEP in nanodiscs, revealing the basis of small-molecule inhibition. Glibenclamide binds the apex of a central binding pocket between the transmembrane domains, preventing BSEP from undergoing conformational changes, and thus rationalizing the reduced uptake of bile salts. We further report two high-resolution structures of BSEP trapped in distinct nucleotide-bound states by using a catalytically inactivated BSEP variant (BSEPE1244Q) to visualize a pre-hydrolysis state, and wild-type BSEP trapped by vanadate to visualize a post-hydrolysis state. Our studies provide structural and functional insight into the mechanism of bile salt extrusion and into small-molecule inhibition of BSEP, which may rationalize drug-induced liver toxicity.
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Affiliation(s)
- Hongtao Liu
- Institute of Molecular Biology and Biophysics, ETH Zürich, Zürich, Switzerland
| | | | - Julia Kowal
- Institute of Molecular Biology and Biophysics, ETH Zürich, Zürich, Switzerland
| | - Dongchun Ni
- Laboratory of Biological Electron Microscopy, Institute of Physics, School of Basic Science, EPFL, and Department of Fundamental Microbiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Kamil Nosol
- Institute of Molecular Biology and Biophysics, ETH Zürich, Zürich, Switzerland
| | - Rose Bang-Sørensen
- Institute of Molecular Biology and Biophysics, ETH Zürich, Zürich, Switzerland
| | - Loïck Lancien
- Institute of Molecular Biology and Biophysics, ETH Zürich, Zürich, Switzerland
| | - Henning Stahlberg
- Laboratory of Biological Electron Microscopy, Institute of Physics, School of Basic Science, EPFL, and Department of Fundamental Microbiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Bruno Stieger
- Institute of Molecular Biology and Biophysics, ETH Zürich, Zürich, Switzerland
| | - Kaspar P Locher
- Institute of Molecular Biology and Biophysics, ETH Zürich, Zürich, Switzerland.
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11
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Chen D, Rehfeld JF, Watts AG, Rorsman P, Gundlach AL. History of key regulatory peptide systems and perspectives for future research. J Neuroendocrinol 2023; 35:e13251. [PMID: 37053148 DOI: 10.1111/jne.13251] [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: 01/09/2023] [Revised: 02/10/2023] [Accepted: 02/26/2023] [Indexed: 03/06/2023]
Abstract
Throughout the 20th Century, regulatory peptide discovery advanced from the identification of gut hormones to the extraction and characterization of hypothalamic hypophysiotropic factors, and to the isolation and cloning of multiple brain neuropeptides. These discoveries were followed by the discovery of G-protein-coupled and other membrane receptors for these peptides. Subsequently, the systems physiology associated with some of these multiple regulatory peptides and receptors has been comprehensively elucidated and has led to improved therapeutics and diagnostics and their approval by the US Food and Drug Administration. In light of this wealth of information and further potential, it is truly a time of renaissance for regulatory peptides. In this perspective, we review what we have learned from the pioneers in exemplified fields of gut peptides, such as cholecystokinin, enterochromaffin-like-cell peptides, and glucagon, from the trailblazing studies on the key stress hormone, corticotropin-releasing factor, as well as from more recently characterized relaxin-family peptides and receptors. The historical viewpoints are based on our understanding of these topics in light of the earliest phases of research and on subsequent studies and the evolution of knowledge, aiming to sharpen our vision of the current state-of-the-art and those studies that should be prioritized in the future.
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Affiliation(s)
- Duan Chen
- Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Jens F Rehfeld
- Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Alan G Watts
- Department of Biological Sciences, Dornsife College of Letters, Arts and Sciences, University of Southern California, Los Angeles, California, USA
| | - Patrik Rorsman
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Andrew L Gundlach
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, VIC, Australia
- Florey Department of Neuroscience and Mental Health and Department of Anatomy and Physiology, The University of Melbourne, Melbourne, VIC, Australia
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12
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Suzawa M, Bland ML. Insulin signaling in development. Development 2023; 150:dev201599. [PMID: 37847145 PMCID: PMC10617623 DOI: 10.1242/dev.201599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2023]
Abstract
Nutrient intake is obligatory for animal growth and development, but nutrients alone are not sufficient. Indeed, insulin and homologous hormones are required for normal growth even in the presence of nutrients. These hormones communicate nutrient status between organs, allowing animals to coordinate growth and metabolism with nutrient supply. Insulin and related hormones, such as insulin-like growth factors and insulin-like peptides, play important roles in development and metabolism, with defects in insulin production and signaling leading to hyperglycemia and diabetes. Here, we describe the insulin hormone family and the signal transduction pathways activated by these hormones. We highlight the roles of insulin signaling in coordinating maternal and fetal metabolism and growth during pregnancy, and we describe how secretion of insulin is regulated at different life stages. Additionally, we discuss the roles of insulin signaling in cell growth, stem cell proliferation and cell differentiation. We provide examples of the role of insulin in development across multiple model organisms: Caenorhabditis elegans, Drosophila, zebrafish, mouse and human.
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Affiliation(s)
- Miyuki Suzawa
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA
| | - Michelle L. Bland
- Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA
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13
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Fisher C, Johnson K, Moore M, Sadrati A, Janecek JL, Graham ML, Klein AH. Loss of ATP-sensitive channel expression and function decreases opioid sensitivity in a mouse model of type 2 diabetes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.06.556526. [PMID: 37732180 PMCID: PMC10508758 DOI: 10.1101/2023.09.06.556526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/22/2023]
Abstract
During diabetes, β-cell dysfunction due to loss of potassium channels sensitive to ATP, known as KATP channels occurs progressively over time contributing to hyperglycemia. KATP channels are additionally present in the central and peripheral nervous systems and are downstream targets of opioid receptor signaling. The aim of this study is to investigate if KATP channel expression or activity in the nervous system changes in diabetic mice and if morphine antinociception changes in mice fed a high fat diet (HFD) for 16 weeks compared to controls. Mechanical thresholds were also monitored before and after administration of glyburide or nateglinide, KATP channel antagonists, for four weeks. HFD mice have decreased antinociception to systemic morphine, which is exacerbated after systemic treatment with glyburide or nateglinide. HFD mice also have lower rotarod scores, decreased mobility in an open field test, and lower burrowing behavior compared to their control diet counterparts, which is unaffected by KATP channel antagonist delivery. Expression of KATP channel subunits, Kcnj11 (Kir6.2) and Abcc8 (SUR1), were decreased in the peripheral and central nervous system in HFD mice, which is significantly correlated with baseline paw withdrawal thresholds. Upregulation of SUR1 through an adenovirus delivered intrathecally increased morphine antinociception in HFD mice, whereas Kir6.2 upregulation improved morphine antinociception only marginally. Perspective: This article presents the potential link between KATP channel function and neuropathy during diabetes. There is a need for increased knowledge in how diabetes affects structural and molecular changes in the nervous system to lead to the progression of chronic pain and sensory issues.
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Affiliation(s)
- Cole Fisher
- Department of Pharmacy Practice and Pharmaceutical Sciences, University of Minnesota, Duluth, MN, USA
| | - Kayla Johnson
- Department of Pharmacy Practice and Pharmaceutical Sciences, University of Minnesota, Duluth, MN, USA
| | - Madelyn Moore
- Department of Pharmacy Practice and Pharmaceutical Sciences, University of Minnesota, Duluth, MN, USA
| | - Amir Sadrati
- Department of Pharmacy Practice and Pharmaceutical Sciences, University of Minnesota, Duluth, MN, USA
| | - Jody L. Janecek
- Department of Surgery, University of Minnesota, St. Paul, MN, USA
| | | | - Amanda H. Klein
- Department of Pharmacy Practice and Pharmaceutical Sciences, University of Minnesota, Duluth, MN, USA
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14
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Lang AL, Nissanka N, Louzada RA, Tamayo A, Pereira E, Moraes CT, Caicedo A. A Defect in Mitochondrial Complex III but Not in Complexes I or IV Causes Early β-Cell Dysfunction and Hyperglycemia in Mice. Diabetes 2023; 72:1262-1276. [PMID: 37343239 PMCID: PMC10451017 DOI: 10.2337/db22-0728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Accepted: 06/04/2023] [Indexed: 06/23/2023]
Abstract
Mitochondrial metabolism and oxidative respiration are crucial for pancreatic β-cell function and stimulus secretion coupling. Oxidative phosphorylation (OxPhos) produces ATP and other metabolites that potentiate insulin secretion. However, the contribution of individual OxPhos complexes to β-cell function is unknown. We generated β-cell-specific, inducible OxPhos complex knock-out (KO) mouse models to investigate the effects of disrupting complex I, complex III, or complex IV on β-cell function. Although all KO models had similar mitochondrial respiratory defects, complex III caused early hyperglycemia, glucose intolerance, and loss of glucose-stimulated insulin secretion in vivo. However, ex vivo insulin secretion did not change. Complex I and IV KO models showed diabetic phenotypes much later. Mitochondrial Ca2+ responses to glucose stimulation 3 weeks after gene deletion ranged from not affected to severely disrupted, depending on the complex targeted, supporting the unique roles of each complex in β-cell signaling. Mitochondrial antioxidant enzyme immunostaining increased in islets from complex III KO, but not from complex I or IV KO mice, indicating that severe diabetic phenotype in the complex III-deficient mice is causing alterations in cellular redox status. The present study highlights that defects in individual OxPhos complexes lead to different pathogenic outcomes. ARTICLE HIGHLIGHTS Mitochondrial metabolism is critical for β-cell insulin secretion, and mitochondrial dysfunction is involved in type 2 diabetes pathogenesis. We determined whether individual oxidative phosphorylation complexes contribute uniquely to β-cell function. Compared with loss of complex I and IV, loss of complex III resulted in severe in vivo hyperglycemia and altered β-cell redox status. Loss of complex III altered cytosolic and mitochondrial Ca2+ signaling and increased expression of glycolytic enzymes. Individual complexes contribute differently to β-cell function. This underscores the role of mitochondrial oxidative phosphorylation complex defects in diabetes pathogenesis.
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Affiliation(s)
- Anna L. Lang
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL
| | - Nadee Nissanka
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL
| | - Ruy A. Louzada
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Miami Miller School of Medicine, Miami, FL
| | - Alejandro Tamayo
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Miami Miller School of Medicine, Miami, FL
- Department of Molecular Cell and Developmental Biology, University of Miami Miller School of Medicine, Miami, FL
| | - Elizabeth Pereira
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Miami Miller School of Medicine, Miami, FL
| | - Carlos T. Moraes
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL
| | - Alejandro Caicedo
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Miami Miller School of Medicine, Miami, FL
- Department of Molecular Cell and Developmental Biology, University of Miami Miller School of Medicine, Miami, FL
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15
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Frederico MJS, Cipriani A, Heim JBA, Mendes AKB, Aragón M, Gaspar JM, De Alencar NMN, Silva FRMB. Electrophilic Agonists Modulate the Transient Receptor Potential Ankyrin-1 Channels Mediated by Insulin and Glucagon-like Peptide-1 Secretion for Glucose Homeostasis. Pharmaceuticals (Basel) 2023; 16:1167. [PMID: 37631083 PMCID: PMC10458466 DOI: 10.3390/ph16081167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 08/07/2023] [Accepted: 08/09/2023] [Indexed: 08/27/2023] Open
Abstract
This pre-clinical study investigated the transient receptor potential ankyrin-1 (TRPA1) channels on modulating targets for glucose homeostasis using agonists: the electrophilic agonists, cinnamaldehyde (CIN) and allyl isothiocyanate (AITC), and the non-electrophilic agonist, carvacrol (CRV). A glucose tolerance test was performed on rats. CIN and AITC (5, 10 and 20 mg/kg) or CRV (25, 100, 300, and 600 mg/kg) were administered intraperitoneally (i.p.), and glycemia was measured. In the intestine, Glucagon-like peptide-1 (GLP-1) and disaccharidase activity were evaluated (in vivo and in vitro, respectively). Furthermore, in vivo and in vitro insulin secretion was determined. Islets were used to measure insulin secretion and calcium influx. CIN and AITC improved glucose tolerance and increased insulin secretion in vivo and in vitro. CRV was unable to reduce glycemia. Electrophilic agonists, CIN and AITC, inhibited disaccharidases and acted as secretagogues in the intestine by inducing GLP-1 release in vivo and in vitro and contributed to insulin secretion and glycemia. The effect of CIN on calcium influx in pancreatic islets (insulin secretion) involves voltage-dependent calcium channels and calcium from stores. TRPA1 triggers calcium influx and potentiates intracellular calcium release to induce insulin secretion, suggesting that electrophilic agonists mediate this signaling transduction for the control of glycemia.
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Affiliation(s)
- Marisa Jadna Silva Frederico
- Laboratory of Hormones & Signal Transduction, Departament of Biochemistry, Center of Biological Sciences, Campus Trindade, Federal University of Santa Catarina, Florianópolis 88040-900, SC, Brazil; (A.C.); (J.B.A.H.); (A.K.B.M.); (J.M.G.)
- Laboratory of Biochemistry and Pharmacology, Departament of Pharmacology and Physiology, Drug Research and Development Center (DRDC), Medical School, Federal University of Ceará, Rua Coronel Nunes de Melo, Fortaleza 60430-275, CE, Brazil;
| | - Andreza Cipriani
- Laboratory of Hormones & Signal Transduction, Departament of Biochemistry, Center of Biological Sciences, Campus Trindade, Federal University of Santa Catarina, Florianópolis 88040-900, SC, Brazil; (A.C.); (J.B.A.H.); (A.K.B.M.); (J.M.G.)
| | - Jocelyn Brice Alexandre Heim
- Laboratory of Hormones & Signal Transduction, Departament of Biochemistry, Center of Biological Sciences, Campus Trindade, Federal University of Santa Catarina, Florianópolis 88040-900, SC, Brazil; (A.C.); (J.B.A.H.); (A.K.B.M.); (J.M.G.)
| | - Ana Karla Bittencourt Mendes
- Laboratory of Hormones & Signal Transduction, Departament of Biochemistry, Center of Biological Sciences, Campus Trindade, Federal University of Santa Catarina, Florianópolis 88040-900, SC, Brazil; (A.C.); (J.B.A.H.); (A.K.B.M.); (J.M.G.)
| | - Marcela Aragón
- Departament of Pharmacy, Science School, National University of Colombia, Bogotá 11011, Colombia;
| | - Joana Margarida Gaspar
- Laboratory of Hormones & Signal Transduction, Departament of Biochemistry, Center of Biological Sciences, Campus Trindade, Federal University of Santa Catarina, Florianópolis 88040-900, SC, Brazil; (A.C.); (J.B.A.H.); (A.K.B.M.); (J.M.G.)
| | - Nylane Maria Nunes De Alencar
- Laboratory of Biochemistry and Pharmacology, Departament of Pharmacology and Physiology, Drug Research and Development Center (DRDC), Medical School, Federal University of Ceará, Rua Coronel Nunes de Melo, Fortaleza 60430-275, CE, Brazil;
| | - Fátima Regina Mena Barreto Silva
- Laboratory of Hormones & Signal Transduction, Departament of Biochemistry, Center of Biological Sciences, Campus Trindade, Federal University of Santa Catarina, Florianópolis 88040-900, SC, Brazil; (A.C.); (J.B.A.H.); (A.K.B.M.); (J.M.G.)
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16
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Takamori M, Mitoh Y, Horie K, Egusa M, Miyawaki T, Yoshida R. Sugar signals from oral glucose transporters elicit cephalic-phase insulin release in mice. J Physiol Sci 2023; 73:16. [PMID: 37525102 DOI: 10.1186/s12576-023-00875-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 07/23/2023] [Indexed: 08/02/2023]
Abstract
Cephalic-phase insulin release (CPIR) occurs before blood glucose increases after a meal. Although glucose is the most plausible cue to induce CPIR, peripheral sensory systems involved are not fully elucidated. We therefore examined roles of sweet sensing by a T1R3-dependent taste receptor and sugar sensing by oral glucose transporters in the oropharyngeal region in inducing CPIR. Spontaneous oral ingestion of glucose significantly increased plasma insulin 5 min later in wild-type (C57BL/6) and T1R3-knockout mice, but intragastric infusion did not. Oral treatment of glucose transporter inhibitors phlorizin and phloretin significantly reduced CPIR after spontaneous oral ingestion. In addition, a rapid increase in plasma insulin was significantly smaller in WT mice with spontaneous oral ingestion of nonmetabolizable glucose analog than in WT mice with spontaneous oral ingestion of glucose. Taken together, the T1R3-dependent receptor is not required for CPIR, but oral glucose transporters greatly contribute to induction of CPIR by sugars.
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Affiliation(s)
- Mitsuhito Takamori
- Department of Oral Physiology, Graduate School of Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, 700-8525, Japan
- Department of Dental Anesthesiology and Special Care Dentistry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Yoshihiro Mitoh
- Department of Oral Physiology, Graduate School of Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, 700-8525, Japan
- Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1, Shikata-Cho, Kita-Ku, Okayama, 700-8525, Japan
- Advanced Research Center for Oral and Craniofacial Sciences, Okayama University Dental School, Okayama, Japan
| | - Kengo Horie
- Department of Oral Physiology, Graduate School of Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, 700-8525, Japan
- Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1, Shikata-Cho, Kita-Ku, Okayama, 700-8525, Japan
| | - Masahiko Egusa
- The Center for Special Needs Dentistry, Okayama University Hospital, Okayama, Japan
| | - Takuya Miyawaki
- Department of Dental Anesthesiology and Special Care Dentistry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
- Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1, Shikata-Cho, Kita-Ku, Okayama, 700-8525, Japan
| | - Ryusuke Yoshida
- Department of Oral Physiology, Graduate School of Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, 700-8525, Japan.
- Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1, Shikata-Cho, Kita-Ku, Okayama, 700-8525, Japan.
- Advanced Research Center for Oral and Craniofacial Sciences, Okayama University Dental School, Okayama, Japan.
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17
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Yan X, Liu X, Zhao C, Chen GQ. Applications of synthetic biology in medical and pharmaceutical fields. Signal Transduct Target Ther 2023; 8:199. [PMID: 37169742 PMCID: PMC10173249 DOI: 10.1038/s41392-023-01440-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 03/15/2023] [Accepted: 03/24/2023] [Indexed: 05/13/2023] Open
Abstract
Synthetic biology aims to design or assemble existing bioparts or bio-components for useful bioproperties. During the past decades, progresses have been made to build delicate biocircuits, standardized biological building blocks and to develop various genomic/metabolic engineering tools and approaches. Medical and pharmaceutical demands have also pushed the development of synthetic biology, including integration of heterologous pathways into designer cells to efficiently produce medical agents, enhanced yields of natural products in cell growth media to equal or higher than that of the extracts from plants or fungi, constructions of novel genetic circuits for tumor targeting, controllable releases of therapeutic agents in response to specific biomarkers to fight diseases such as diabetes and cancers. Besides, new strategies are developed to treat complex immune diseases, infectious diseases and metabolic disorders that are hard to cure via traditional approaches. In general, synthetic biology brings new capabilities to medical and pharmaceutical researches. This review summarizes the timeline of synthetic biology developments, the past and present of synthetic biology for microbial productions of pharmaceutics, engineered cells equipped with synthetic DNA circuits for diagnosis and therapies, live and auto-assemblied biomaterials for medical treatments, cell-free synthetic biology in medical and pharmaceutical fields, and DNA engineering approaches with potentials for biomedical applications.
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Affiliation(s)
- Xu Yan
- School of Life Sciences, Tsinghua University, 100084, Beijing, China
| | - Xu Liu
- PhaBuilder Biotech Co. Ltd., Shunyi District, Zhaoquan Ying, 101309, Beijing, China
| | - Cuihuan Zhao
- School of Life Sciences, Tsinghua University, 100084, Beijing, China
| | - Guo-Qiang Chen
- School of Life Sciences, Tsinghua University, 100084, Beijing, China.
- Center for Synthetic and Systems Biology, Tsinghua University, 100084, Beijing, China.
- MOE Key Lab for Industrial Biocatalysis, Dept Chemical Engineering, Tsinghua University, 100084, Beijing, China.
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18
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Serbis A, Giapros V, Tsamis K, Balomenou F, Galli-Tsinopoulou A, Siomou E. Beta Cell Dysfunction in Youth- and Adult-Onset Type 2 Diabetes: An Extensive Narrative Review with a Special Focus on the Role of Nutrients. Nutrients 2023; 15:2217. [PMID: 37432389 PMCID: PMC10180650 DOI: 10.3390/nu15092217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 05/04/2023] [Accepted: 05/06/2023] [Indexed: 07/12/2023] Open
Abstract
Traditionally a disease of adults, type 2 diabetes (T2D) has been increasingly diagnosed in youth, particularly among adolescents and young adults of minority ethnic groups. Especially, during the recent COVID-19 pandemic, obesity and prediabetes have surged not only in minority ethnic groups but also in the general population, further raising T2D risk. Regarding its pathogenesis, a gradually increasing insulin resistance due to central adiposity combined with a progressively defective β-cell function are the main culprits. Especially in youth-onset T2D, a rapid β-cell activity decline has been observed, leading to higher treatment failure rates, and early complications. In addition, it is well established that both the quantity and quality of food ingested by individuals play a key role in T2D pathogenesis. A chronic imbalance between caloric intake and expenditure together with impaired micronutrient intake can lead to obesity and insulin resistance on one hand, and β-cell failure and defective insulin production on the other. This review summarizes our evolving understanding of the pathophysiological mechanisms involved in defective insulin secretion by the pancreatic islets in youth- and adult-onset T2D and, further, of the role various micronutrients play in these pathomechanisms. This knowledge is essential if we are to curtail the serious long-term complications of T2D both in pediatric and adult populations.
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Affiliation(s)
- Anastasios Serbis
- Department of Pediatrics, School of Medicine, University of Ioannina, St. Niarhcos Avenue, 45500 Ioannina, Greece;
| | - Vasileios Giapros
- Neonatal Intensive Care Unit, School of Medicine, University of Ioannina, St. Νiarhcos Avenue, 45500 Ioannina, Greece (F.B.)
| | - Konstantinos Tsamis
- Department of Physiology, Faculty of Medicine, School of Health Sciences, University of Ioannina, St. Niarhcos Avenue, 45500 Ioannina, Greece
| | - Foteini Balomenou
- Neonatal Intensive Care Unit, School of Medicine, University of Ioannina, St. Νiarhcos Avenue, 45500 Ioannina, Greece (F.B.)
| | - Assimina Galli-Tsinopoulou
- Second Department of Pediatrics, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, AHEPA University Hospital, Stilponos Kyriakidi 1, 54636 Thessaloniki, Greece;
| | - Ekaterini Siomou
- Department of Pediatrics, School of Medicine, University of Ioannina, St. Niarhcos Avenue, 45500 Ioannina, Greece;
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19
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Nam YH, Kim EB, Kang JE, Kim JS, Jeon Y, Shin SW, Kang TH, Kwak JH. Ameliorative Effects of Flavonoids from Platycodon grandiflorus Aerial Parts on Alloxan-Induced Pancreatic Islet Damage in Zebrafish. Nutrients 2023; 15:nu15071798. [PMID: 37049638 PMCID: PMC10096680 DOI: 10.3390/nu15071798] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/03/2023] [Accepted: 04/04/2023] [Indexed: 04/14/2023] Open
Abstract
Platycodon grandiflorus (balloon flower), used as a food reserve as well as in traditional herbal medicine, is known for its multiple beneficial effects. In particular, this plant is widely used as a vegetable in Republic of Korea. We examined the ameliorative effects of P. grandiflorus on alloxan-induced pancreatic islet damage in zebrafish. The aerial part treatment led to a significant recovery in pancreatic islet size and glucose uptake. The efficacy of the aerial part was more potent than that of the root. Eight flavonoids (1-8) were isolated from the aerial part. Structures of two new flavone glycosides, designated dorajiside I (1) and II (2), were elucidated to be luteolin 7-O-α-L-rhamno-pyranosyl (1 → 2)-(6-O-acetyl)-β-D-glucopyranoside and apigenin 7-O-α-L-rhamnopyranosyl (1 → 2)-(6-O-acetyl)-β-D-glucopyranoside, respectively, by spectroscopic analysis. Compounds 1, 3, 4 and 6-8 yielded the recovery of injured pancreatic islets in zebrafish. Among them, compound 7 blocked KATP channels in pancreatic β-cells. Furthermore, compounds 3, 4, 6 and 7 showed significant changes with respect to the mRNA expression of GCK, GCKR, GLIS3 and CDKN2B compared to alloxan-induced zebrafish. In conclusion, the aerial part of P. grandiflorus and its constituents conferred a regenerative effect on injured pancreatic islets.
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Affiliation(s)
- Youn Hee Nam
- Department of Oriental Medicine Biotechnology, College of Life Sciences and Graduate School of Biotechnology, Kyung Hee University, Global Campus, Yongin 17104, Republic of Korea
| | - Eun Bin Kim
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Ji Eun Kang
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Ju Su Kim
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Yukyoung Jeon
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Sung Woo Shin
- Department of Oriental Medicine Biotechnology, College of Life Sciences and Graduate School of Biotechnology, Kyung Hee University, Global Campus, Yongin 17104, Republic of Korea
| | - Tong Ho Kang
- Department of Oriental Medicine Biotechnology, College of Life Sciences and Graduate School of Biotechnology, Kyung Hee University, Global Campus, Yongin 17104, Republic of Korea
| | - Jong Hwan Kwak
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, Republic of Korea
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20
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Alsup AM, Fowlds K, Cho M, Luber JM. BetaBuddy: An end-to-end computer vision pipeline for the automated analysis of insulin secreting β-cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.06.535890. [PMID: 37066375 PMCID: PMC10104060 DOI: 10.1101/2023.04.06.535890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Abstract
Insulin secretion from pancreatic β-cells is integral in maintaining the delicate equilibrium of blood glucose levels. Calcium is known to be a key regulator and triggers the release of insulin. This sub-cellular process can be monitored and tracked through live-cell imaging and subsequent cell segmentation, registration, tracking, and analysis of the calcium level in each cell. Current methods of analysis typically require the manual outlining of β-cells, involve multiple software packages, and necessitate multiple researchers - all of which tend to introduce biases. Utilizing deep learning algorithms, we have therefore created a pipeline to automatically segment and track thousands of cells, which greatly reduces the time required to gather and analyze a large number of sub-cellular images and improve accuracy. Tracking cells over a time-series image stack also allows researchers to isolate specific calcium spiking patterns and spatially identify those of interest, creating an efficient and user-friendly analysis tool. Using our automated pipeline, a previous dataset used to evaluate changes in calcium spiking activity in β-cells post-electric field stimulation was reanalyzed. Changes in spiking activity were found to be underestimated previously with manual segmentation. Moreover, the machine learning pipeline provides a powerful and rapid computational approach to examine, for example, how calcium signaling is regulated by intracellular interactions in a cluster of β-cells.
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Affiliation(s)
- Anne M. Alsup
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, United States of America
| | - Kelli Fowlds
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, United States of America
| | - Michael Cho
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, United States of America
| | - Jacob M. Luber
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, United States of America
- Department of Computer Science and Engineering, University of Texas at Arlington, Arlington, TX, United States of America
- Multi-Interprofessional Center for Health Informatics, University of Texas at Arlington, Arlington, TX, United States of America
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21
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Suwara J, Radzikowska-Cieciura E, Chworos A, Pawlowska R. The ATP-dependent Pathways and Human Diseases. Curr Med Chem 2023; 30:1232-1255. [PMID: 35319356 DOI: 10.2174/0929867329666220322104552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Revised: 12/31/2021] [Accepted: 01/04/2022] [Indexed: 11/22/2022]
Abstract
Adenosine triphosphate (ATP) is one of the most important molecules of life, present both inside the cells and extracellularly. It is an essential building block for nucleic acids biosynthesis and crucial intracellular energy storage. However, one of the most interesting functions of ATP is the role of a signaling molecule. Numerous studies indicate the involvement of ATP-dependent pathways in maintaining the proper functioning of individual tissues and organs. Herein, the latest data indicating the ATP function in the network of intra- and extracellular signaling pathways including purinergic signaling, MAP kinase pathway, mTOR and calcium signaling are collected. The main ATP-dependent processes maintaining the proper functioning of the nervous, cardiovascular and immune systems, as well as skin and bones, are summarized. The disturbances in the ATP amount, its cellular localization, or interaction with target elements may induce pathological changes in signaling pathways leading to the development of serious diseases. The impact of an ATP imbalance on the development of dangerous health dysfunctions such as neurodegeneration diseases, cardiovascular diseases (CVDs), diabetes mellitus, obesity, cancers and immune pathogenesis are discussed here.
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Affiliation(s)
- Justyna Suwara
- Department of Bioorganic Chemistry, Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363, Lodz, Poland
| | - Ewa Radzikowska-Cieciura
- Department of Bioorganic Chemistry, Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363, Lodz, Poland
| | - Arkadiusz Chworos
- Department of Bioorganic Chemistry, Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363, Lodz, Poland
| | - Roza Pawlowska
- Department of Bioorganic Chemistry, Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363, Lodz, Poland
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22
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Andrean D, Pedersen MG. Machine learning provides insight into models of heterogeneous electrical activity in human beta-cells. Math Biosci 2022; 354:108927. [PMID: 36332730 DOI: 10.1016/j.mbs.2022.108927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 10/20/2022] [Accepted: 10/21/2022] [Indexed: 11/06/2022]
Abstract
Understanding how heterogeneous cellular responses emerge from cell-to-cell variations in expression and function of subcellular components is of general interest. Here, we focus on human insulin-secreting beta-cells, which are believed to constitute a population in which heterogeneity is of physiological importance. We exploit recent single-cell electrophysiological data that allow biologically realistic population modeling of human beta-cells that accounts for cellular heterogeneity and correlation between ion channel parameters. To investigate how ion channels influence the dynamics of our updated mathematical model of human pancreatic beta-cells, we explore several machine learning techniques to determine which model parameters are important for determining the qualitative patterns of electrical activity of the model cells. As expected, K+ channels promote absence of activity, but once a cell is active, they increase the likelihood of having action potential firing. HERG channels were of great importance for determining cell behavior in most of the investigated scenarios. Fast bursting is influenced by the time scales of ion channel activation and, interestingly, by the type of Ca2+ channels coupled to BK channels in BK-CaV complexes. Slow, metabolically driven oscillations are promoted mostly by K(ATP) channels. In summary, combining population modeling with machine learning analysis provides insight into the model and generates new hypotheses to be investigated both experimentally, via simulations and through mathematical analysis.
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Affiliation(s)
- Daniele Andrean
- Department of Information Engineering, University of Padova, Via Gradenigo 6/b, I-35131 Padova, Italy
| | - Morten Gram Pedersen
- Department of Information Engineering, University of Padova, Via Gradenigo 6/b, I-35131 Padova, Italy.
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23
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Liu J, Li X, Xu N, Han H, Li X. Role of ion channels in the mechanism of proteinuria (Review). Exp Ther Med 2022; 25:27. [PMID: 36561615 PMCID: PMC9748662 DOI: 10.3892/etm.2022.11726] [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: 07/01/2022] [Accepted: 10/10/2022] [Indexed: 11/25/2022] Open
Abstract
Proteinuria is a common clinical manifestation of kidney diseases, such as glomerulonephritis, nephrotic syndrome, immunoglobulin A nephropathy and diabetic nephropathy. Therefore, proteinuria is considered to be a risk factor for renal dysfunction. Furthermore, proteinuria is also significantly associated with the progression of kidney diseases and increased mortality. Its occurrence is closely associated with damage to the structure of the glomerular filtration membrane. An impaired glomerular filtration membrane can affect the selective filtration function of the kidneys; therefore, several macromolecular substances, such as proteins, may pass through the filtration membrane and promote the manifestation of proteinuria. It has been reported that ion channels play a significant role in the mechanisms underlying proteinuria. Ion channel mutations or other dysfunctions have been implicated in several diseases, therefore ion channels could be used as major therapeutic targets. The mechanisms underlying the action of ion channels and ion transporters in proteinuria have been overlooked in the literature, despite their importance in identifying novel targets for treating proteinuria and delaying the progression of kidney diseases. The current review article focused on the four key ion channel groups, namely Na+, Ca2+, Cl- and K+ ion channels and the associated ion transporters.
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Affiliation(s)
- Jie Liu
- Department of Nephrology, Affiliated Hospital of Weifang Medical University, Weifang, Shandong 261000, P.R. China
| | - Xuewei Li
- Department of Rheumatology, Affiliated Hospital of Weifang Medical University, Weifang, Shandong 261000, P.R. China
| | - Ning Xu
- Department of Nephrology, Affiliated Hospital of Weifang Medical University, Weifang, Shandong 261000, P.R. China
| | - Huirong Han
- Department of Anesthesiology, Weifang Medical University, Weifang, Shandong 261000, P.R. China
| | - Xiangling Li
- Department of Nephrology, Affiliated Hospital of Weifang Medical University, Weifang, Shandong 261000, P.R. China,Correspondence to: Professor Xiangling Li, Department of Nephrology, Affiliated Hospital of Weifang Medical University, 2428 Yu He Road, Weifang, Shandong 261000, P.R. China
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24
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Ansari P, Hannan JMA, Choudhury ST, Islam SS, Talukder A, Seidel V, Abdel-Wahab YHA. Antidiabetic Actions of Ethanol Extract of Camellia sinensis Leaf Ameliorates Insulin Secretion, Inhibits the DPP-IV Enzyme, Improves Glucose Tolerance, and Increases Active GLP-1 (7-36) Levels in High-Fat-Diet-Fed Rats. MEDICINES (BASEL, SWITZERLAND) 2022; 9:medicines9110056. [PMID: 36422117 PMCID: PMC9698069 DOI: 10.3390/medicines9110056] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Revised: 11/04/2022] [Accepted: 11/09/2022] [Indexed: 05/14/2023]
Abstract
Camellia sinensis (green tea) is used in traditional medicine to treat a wide range of ailments. In the present study, the insulin-releasing and glucose-lowering effects of the ethanol extract of Camellia sinensis (EECS), along with molecular mechanism/s of action, were investigated in vitro and in vivo. The insulin secretion was measured using clonal pancreatic BRIN BD11 β cells, and mouse islets. In vitro models examined the additional glucose-lowering properties of EECS, and 3T3L1 adipocytes were used to assess glucose uptake and insulin action. Non-toxic doses of EECS increased insulin secretion in a concentration-dependent manner, and this regulatory effect was similar to that of glucagon-like peptide 1 (GLP-1). The insulin release was further enhanced when combined with isobutylmethylxanthine (IBMX), tolbutamide or 30 mM KCl, but was decreased in the presence of verapamil, diazoxide and Ca2+ chelation. EECS also depolarized the β-cell membrane and elevated intracellular Ca2+, suggesting the involvement of a KATP-dependent pathway. Furthermore, EECS increased glucose uptake and insulin action in 3T3-L1 cells and inhibited dipeptidyl peptidase IV (DPP-IV) enzyme activity, starch digestion and protein glycation in vitro. Oral administration of EECS improved glucose tolerance and plasma insulin as well as inhibited plasma DPP-IV and increased active GLP-1 (7-36) levels in high-fat-diet-fed rats. Flavonoids and other phytochemicals present in EECS could be responsible for these effects. Further research on the mechanism of action of EECS compounds could lead to the development of cost-effective treatments for type 2 diabetes.
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Affiliation(s)
- Prawej Ansari
- Department of Pharmacy, School of Pharmacy and Public Health, Independent University, Bangladesh (IUB), Dhaka 1229, Bangladesh
- School of Biomedical Sciences, Ulster University, Coleraine BT52 1SA, UK
- Correspondence:
| | - J. M. A. Hannan
- Department of Pharmacy, School of Pharmacy and Public Health, Independent University, Bangladesh (IUB), Dhaka 1229, Bangladesh
| | - Samara T. Choudhury
- Department of Pharmacy, School of Pharmacy and Public Health, Independent University, Bangladesh (IUB), Dhaka 1229, Bangladesh
| | - Sara S. Islam
- Department of Pharmacy, School of Pharmacy and Public Health, Independent University, Bangladesh (IUB), Dhaka 1229, Bangladesh
| | - Abdullah Talukder
- Department of Pharmacy, School of Pharmacy and Public Health, Independent University, Bangladesh (IUB), Dhaka 1229, Bangladesh
| | - Veronique Seidel
- Natural Products Research Laboratory, Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow G4 0RE, UK
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25
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McClenaghan C, Nichols CG. Kir6.1 and SUR2B in Cantú syndrome. Am J Physiol Cell Physiol 2022; 323:C920-C935. [PMID: 35876283 PMCID: PMC9467476 DOI: 10.1152/ajpcell.00154.2022] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 07/07/2022] [Accepted: 07/07/2022] [Indexed: 12/25/2022]
Abstract
Kir6.1 and SUR2 are subunits of ATP-sensitive potassium (KATP) channels expressed in a wide range of tissues. Extensive study has implicated roles of these channel subunits in diverse physiological functions. Together they generate the predominant KATP conductance in vascular smooth muscle and are the target of vasodilatory drugs. Roles for Kir6.1/SUR2 dysfunction in disease have been suggested based on studies of animal models and human genetic discoveries. In recent years, it has become clear that gain-of-function (GoF) mutations in both genes result in Cantú syndrome (CS)-a complex, multisystem disorder. There is currently no targeted therapy for CS, but studies of mouse models of the disease reveal that pharmacological reversibility of cardiovascular and gastrointestinal pathologies can be achieved by administration of the KATP channel inhibitor, glibenclamide. Here we review the function, structure, and physiological and pathological roles of Kir6.1/SUR2B channels, with a focus on CS. Recent studies have led to much improved understanding of the underlying pathologies and the potential for treatment, but important questions remain: Can the study of genetically defined CS reveal new insights into Kir6.1/SUR2 function? Do these reveal new pathophysiological mechanisms that may be important in more common diseases? And is our pharmacological armory adequately stocked?
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Affiliation(s)
- Conor McClenaghan
- Department of Cell Biology and Physiology, Center for the Investigation of Membrane Excitability Diseases (CIMED), Washington University, St. Louis, Missouri
| | - Colin G Nichols
- Department of Cell Biology and Physiology, Center for the Investigation of Membrane Excitability Diseases (CIMED), Washington University, St. Louis, Missouri
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26
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Spiliotis II, Chalk R, Gough S, Rorsman P. Reducing hyperglucagonaemia in type 2 diabetes using low-dose glibenclamide: Results of the LEGEND-A pilot study. Diabetes Obes Metab 2022; 24:1671-1675. [PMID: 35491519 PMCID: PMC9543075 DOI: 10.1111/dom.14740] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 04/19/2022] [Accepted: 04/28/2022] [Indexed: 01/21/2023]
Affiliation(s)
- Ioannis I. Spiliotis
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of MedicineUniversity of OxfordOxford
| | - Rod Chalk
- Centre for Medicines DiscoveryUniversity of OxfordOxfordUK
| | - Stephen Gough
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of MedicineUniversity of OxfordOxford
| | - Patrik Rorsman
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of MedicineUniversity of OxfordOxford
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27
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Bränström R, Berglund E, Fröbom R, Leibiger IB, Leibiger B, Aspinwall CA, Larsson O, Berggren PO. Inward and outward currents of native and cloned K(ATP) channels (Kir6.2/SUR1) share single-channel kinetic properties. Biochem Biophys Rep 2022; 30:101260. [PMID: 35434386 PMCID: PMC9006676 DOI: 10.1016/j.bbrep.2022.101260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 04/03/2022] [Accepted: 04/04/2022] [Indexed: 11/02/2022] Open
Abstract
Background Methods Results Conclusions Outward K(ATP) channel currents are not grouped in bursts regardless of membrane potential. No differences in the number of kinetic states could be seen for single channels between native K(ATP) channels, Kir6.2ΔC26 alone and co-expressed with SUR1 for outward currents. K(ATP) channel open time for outward currents corresponds to burst duration for inward currents.
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28
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Farnsworth NL, Piscopio RA, Schleicher WE, Ramirez DG, Miranda JG, Benninger RKP. Modulation of Gap Junction Coupling Within the Islet of Langerhans During the Development of Type 1 Diabetes. Front Physiol 2022; 13:913611. [PMID: 35837011 PMCID: PMC9274093 DOI: 10.3389/fphys.2022.913611] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 06/09/2022] [Indexed: 01/07/2023] Open
Abstract
In type 1 diabetes (T1D), islet dysfunction occurs prior to diabetes onset. Pro-inflammatory cytokines can disrupt insulin secretion and Ca2+ homeostasis. Connexin36 (Cx36) gap junctions electrically couple β-cells to coordinate glucose-stimulated Ca2+ and insulin secretion. Cx36 gap junction coupling can also protect against cytokine-induced apoptosis. Our goal was to determine how islet gap junction coupling and Ca2+ dynamics are altered in mouse models of T1D prior to diabetes. Glucose tolerance was assessed in NOD and immunodeficient NOD-RAG1KO mice at 6-12 weeks age. Glucose-stimulated insulin secretion, Ca2+ dynamics, and gap junction coupling were measured in islets isolated at each age. Gap junction coupling was also measured in islets from mice that underwent transfer of diabetogenic splenocytes and from chromograninA knockout NOD mice. Cell death was measured in islets isolated from wild-type, Cx36 knockout or Cx36 over-expression mice, each treated with a cocktail of pro-inflammatory cytokines and KATP or SERCA activators/inhibitors. NOD mice over-expressing Cx36 were also monitored for diabetes development, and islets assessed for insulitis and apoptosis. NOD and NOD-RAG1KO controls showed similar glucose tolerance at all ages. Ca2+ dynamics and gap junction coupling were disrupted in islets of NOD mice at 9 weeks, compared to controls. Transfer of diabetogenic splenocytes also decreased gap junction coupling. Islets from chromograninA knockout mice displayed normal coupling. Overexpression of Cx36 protected islets from cytokine-induced apoptosis. A knockout of Cx36 amplified cytokine-induced apoptosis, which was reversed by KATP activation or SERCA activation. Cx36 overexpression in NOD mice delayed diabetes development compared to NOD controls. However, apoptosis and insulitis were not improved. Decreases in islet gap junction coupling occur prior to T1D onset. Such decreases alter islet susceptibility to apoptosis due to altered Ca2+. Future studies will determine if increasing Cx36 gap junction coupling in combination with restoring Ca2+ homeostasis protects against islet decline in T1D.
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Affiliation(s)
- Nikki L. Farnsworth
- Department of Chemical and Biological Engineering, Colorado School of Mines, Golden, CO, United States,Barbara Davis Center for Diabetes, Universty of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Robert A. Piscopio
- Barbara Davis Center for Diabetes, Universty of Colorado Anschutz Medical Campus, Aurora, CO, United States,Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Wolfgang E. Schleicher
- Barbara Davis Center for Diabetes, Universty of Colorado Anschutz Medical Campus, Aurora, CO, United States,Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - David G. Ramirez
- Barbara Davis Center for Diabetes, Universty of Colorado Anschutz Medical Campus, Aurora, CO, United States,Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Jose G. Miranda
- Barbara Davis Center for Diabetes, Universty of Colorado Anschutz Medical Campus, Aurora, CO, United States,Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Richard K. P. Benninger
- Barbara Davis Center for Diabetes, Universty of Colorado Anschutz Medical Campus, Aurora, CO, United States,Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, CO, United States,*Correspondence: Richard K. P. Benninger,
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29
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Zhao H, Xue S, Hussherr MD, Teixeira AP, Fussenegger M. Autonomous push button-controlled rapid insulin release from a piezoelectrically activated subcutaneous cell implant. SCIENCE ADVANCES 2022; 8:eabm4389. [PMID: 35704573 PMCID: PMC9200281 DOI: 10.1126/sciadv.abm4389] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 04/28/2022] [Indexed: 05/25/2023]
Abstract
Traceless physical cues are desirable for remote control of the in situ production and real-time dosing of biopharmaceuticals in cell-based therapies. However, current optogenetic, magnetogenetic, or electrogenetic devices require sophisticated electronics, complex artificial intelligence-assisted software, and external energy supplies for power and control. Here, we describe a self-sufficient subcutaneous push button-controlled cellular implant powered simply by repeated gentle finger pressure exerted on the overlying skin. Pushing the button causes transient percutaneous deformation of the implant's embedded piezoelectric membrane, which produces sufficient low-voltage energy inside a semi-permeable platinum-coated cell chamber to mediate rapid release of a biopharmaceutical from engineered electro-sensitive human cells. Release is fine-tuned by varying the frequency and duration of finger-pressing stimulation. As proof of concept, we show that finger-pressure activation of the subcutaneous implant can restore normoglycemia in a mouse model of type 1 diabetes. Self-sufficient push-button devices may provide a new level of convenience for patients to control their cell-based therapies.
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Affiliation(s)
- Haijie Zhao
- Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, CH-4058 Basel, Switzerland
| | - Shuai Xue
- Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, CH-4058 Basel, Switzerland
| | - Marie-Didiée Hussherr
- Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, CH-4058 Basel, Switzerland
| | - Ana Palma Teixeira
- Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, CH-4058 Basel, Switzerland
| | - Martin Fussenegger
- Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, CH-4058 Basel, Switzerland
- Faculty of Science, University of Basel, Mattenstrasse 26, CH-4058 Basel, Switzerland
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30
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Li XT. Beneficial effects of carvedilol modulating potassium channels on the control of glucose. Biomed Pharmacother 2022; 150:113057. [PMID: 35658228 DOI: 10.1016/j.biopha.2022.113057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 04/19/2022] [Accepted: 04/26/2022] [Indexed: 11/25/2022] Open
Abstract
The increased prevalence of hypertensive patients with type 2 diabetes mellitus (T2DM) is evident worldwide, leading to a higher risk of cardiovascular disease onset, which is substantially associated with disabilities and mortality in the clinic. In order to achieve the satisfyingly clinical outcomes and prognosis, the comprehensive therapies have been conducted with a beneficial effect on both blood pressure and glucose homeostasis, and clinical trials reveal that some kind of antihypertensive drugs such as angiotensin converting enzyme inhibitors (ACE-I) may, at least in part, meet the dual requirement during the disease management. As a nonselective β-blocker, carvedilol is employed for treating many cardiovascular diseases in clinical practice, including hypertension, angina pectoris and heart failure, and also exhibit the effectiveness for glycemic control and insulin resistance. Apart from alleviating sympathetic nervous system activity, several causes, such as lowering oxygen reactive species, may contribute to the effects of carvedilol on controlling plasma glucose levels, suggesting a feature of this drug having multiple targets. Interestingly, numerous distinct K+ channels expressed in pancreatic β-cells and peripheral insulin-sensitive tissues, which play a sentential role in glucose metabolism, are subjected to extensive modulation of carvdilol, establishing a linkage between K+ channels and drug's effects on the control of glucose. A variety of evidence shows that the impact of carvedilol on different K+ channels, including Kv, KAch, KATP and K2 P, can lead to positive influences for glucose homeostasis, contributing to its clinical beneficial effectiveness in treatment of hypertensive patients with T2DM. This review focus on the control of plasma glucose conferred by carvedilol modulation on K+ channels, providing the novel mechanistic explanation for drug's actions.
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Affiliation(s)
- Xian-Tao Li
- Department of Neuroscience, South-Central University for Nationalities, Wuhan 430074, China; School of Medicine, Guizhou University, Guiyang 550025, China.
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31
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Yang HQ, Echeverry FA, ElSheikh A, Gando I, Anez Arredondo S, Samper N, Cardozo T, Delmar M, Shyng SL, Coetzee WA. Subcellular trafficking and endocytic recycling of K ATP channels. Am J Physiol Cell Physiol 2022; 322:C1230-C1247. [PMID: 35508187 PMCID: PMC9169827 DOI: 10.1152/ajpcell.00099.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 04/27/2022] [Accepted: 04/30/2022] [Indexed: 11/22/2022]
Abstract
Sarcolemmal/plasmalemmal ATP-sensitive K+ (KATP) channels have key roles in many cell types and tissues. Hundreds of studies have described how the KATP channel activity and ATP sensitivity can be regulated by changes in the cellular metabolic state, by receptor signaling pathways and by pharmacological interventions. These alterations in channel activity directly translate to alterations in cell or tissue function, that can range from modulating secretory responses, such as insulin release from pancreatic β-cells or neurotransmitters from neurons, to modulating contractile behavior of smooth muscle or cardiac cells to elicit alterations in blood flow or cardiac contractility. It is increasingly becoming apparent, however, that KATP channels are regulated beyond changes in their activity. Recent studies have highlighted that KATP channel surface expression is a tightly regulated process with similar implications in health and disease. The surface expression of KATP channels is finely balanced by several trafficking steps including synthesis, assembly, anterograde trafficking, membrane anchoring, endocytosis, endocytic recycling, and degradation. This review aims to summarize the physiological and pathophysiological implications of KATP channel trafficking and mechanisms that regulate KATP channel trafficking. A better understanding of this topic has potential to identify new approaches to develop therapeutically useful drugs to treat KATP channel-related diseases.
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Affiliation(s)
- Hua-Qian Yang
- Cyrus Tang Hematology Center, Soochow University, Suzhou, People's Republic of China
| | | | - Assmaa ElSheikh
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, Oregon
- Department of Medical Biochemistry, Tanta University, Tanta, Egypt
| | - Ivan Gando
- Department of Pathology, NYU School of Medicine, New York, New York
| | | | - Natalie Samper
- Department of Pathology, NYU School of Medicine, New York, New York
| | - Timothy Cardozo
- Department of Biochemistry and Molecular Pharmacology, NYU School of Medicine, New York, New York
| | - Mario Delmar
- Department of Biochemistry and Molecular Pharmacology, NYU School of Medicine, New York, New York
- Department of Medicine, NYU School of Medicine, New York, New York
| | - Show-Ling Shyng
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, Oregon
| | - William A Coetzee
- Department of Pathology, NYU School of Medicine, New York, New York
- Department of Neuroscience & Physiology, NYU School of Medicine, New York, New York
- Department of Biochemistry and Molecular Pharmacology, NYU School of Medicine, New York, New York
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32
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Bhatti JS, Sehrawat A, Mishra J, Sidhu IS, Navik U, Khullar N, Kumar S, Bhatti GK, Reddy PH. Oxidative stress in the pathophysiology of type 2 diabetes and related complications: Current therapeutics strategies and future perspectives. Free Radic Biol Med 2022; 184:114-134. [PMID: 35398495 DOI: 10.1016/j.freeradbiomed.2022.03.019] [Citation(s) in RCA: 128] [Impact Index Per Article: 64.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 03/20/2022] [Accepted: 03/22/2022] [Indexed: 02/06/2023]
Abstract
Type 2 diabetes (T2DM) is a persistent metabolic disorder rising rapidly worldwide. It is characterized by pancreatic insulin resistance and β-cell dysfunction. Hyperglycemia induced reactive oxygen species (ROS) production and oxidative stress are correlated with the pathogenesis and progression of this metabolic disease. To counteract the harmful effects of ROS, endogenous antioxidants of the body or exogenous antioxidants neutralise it and maintain bodily homeostasis. Under hyperglycemic conditions, the imbalance between the cellular antioxidant system and ROS production results in oxidative stress, which subsequently results in the development of diabetes. These ROS are produced in the endoplasmic reticulum, phagocytic cells and peroxisomes, with the mitochondrial electron transport chain (ETC) playing a pivotal role. The exacerbated ROS production can directly cause structural and functional modifications in proteins, lipids and nucleic acids. It also modulates several intracellular signaling pathways that lead to insulin resistance and impairment of β-cell function. In addition, the hyperglycemia-induced ROS production contributes to micro- and macro-vascular diabetic complications. Various in-vivo and in-vitro studies have demonstrated the anti-oxidative effects of natural products and their derived bioactive compounds. However, there is conflicting clinical evidence on the beneficial effects of these antioxidant therapies in diabetes prevention. This review article focused on the multifaceted role of oxidative stress caused by ROS overproduction in diabetes and related complications and possible antioxidative therapeutic strategies targeting ROS in this disease.
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Affiliation(s)
- Jasvinder Singh Bhatti
- Department of Human Genetics and Molecular Medicine, School of Health Sciences, Central University of Punjab, Bathinda, India.
| | - Abhishek Sehrawat
- Department of Human Genetics and Molecular Medicine, School of Health Sciences, Central University of Punjab, Bathinda, India.
| | - Jayapriya Mishra
- Department of Human Genetics and Molecular Medicine, School of Health Sciences, Central University of Punjab, Bathinda, India.
| | - Inderpal Singh Sidhu
- Department of Zoology, Sri Guru Gobind Singh College, Sector 26, Chandigarh, India.
| | - Umashanker Navik
- Department of Pharmacology, Central University of Punjab, Bathinda, India.
| | - Naina Khullar
- Department of Zoology, Mata Gujri College, Fatehgarh Sahib, Punjab, India.
| | - Shashank Kumar
- Department of Biochemistry, School of Basic Sciences, Central University of Punjab, Bathinda, India.
| | - Gurjit Kaur Bhatti
- Department of Medical Lab Technology, University Institute of Applied Health Sciences, Chandigarh University, Mohali, India.
| | - P Hemachandra Reddy
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, 79430, USA; Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX, 79430, USA; Department of Public Health, Graduate School of Biomedical Sciences, Texas Tech University Health Sciences Center, Lubbock, TX, 79430, USA; Department of Neurology, Texas Tech University Health Sciences Center, Lubbock, TX, 79430, USA; Department of Speech, Language, and Hearing Sciences, Texas Tech University Health Sciences Center, Lubbock, TX, 79430, USA.
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33
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Molecular dissection of cellular response of pancreatic islet cells to Bisphenol-A (BPA): a comprehensive review. Biochem Pharmacol 2022; 201:115068. [DOI: 10.1016/j.bcp.2022.115068] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 04/11/2022] [Accepted: 04/25/2022] [Indexed: 12/15/2022]
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34
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Galluccio M, Console L, Pochini L, Scalise M, Giangregorio N, Indiveri C. Strategies for Successful Over-Expression of Human Membrane Transport Systems Using Bacterial Hosts: Future Perspectives. Int J Mol Sci 2022; 23:ijms23073823. [PMID: 35409183 PMCID: PMC8998559 DOI: 10.3390/ijms23073823] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 03/28/2022] [Accepted: 03/28/2022] [Indexed: 02/06/2023] Open
Abstract
Ten percent of human genes encode for membrane transport systems, which are key components in maintaining cell homeostasis. They are involved in the transport of nutrients, catabolites, vitamins, and ions, allowing the absorption and distribution of these compounds to the various body regions. In addition, roughly 60% of FDA-approved drugs interact with membrane proteins, among which are transporters, often responsible for pharmacokinetics and side effects. Defects of membrane transport systems can cause diseases; however, knowledge of the structure/function relationships of transporters is still limited. Among the expression of hosts that produce human membrane transport systems, E. coli is one of the most favorable for its low cultivation costs, fast growth, handiness, and extensive knowledge of its genetics and molecular mechanisms. However, the expression in E. coli of human membrane proteins is often toxic due to the hydrophobicity of these proteins and the diversity in structure with respect to their bacterial counterparts. Moreover, differences in codon usage between humans and bacteria hamper translation. This review summarizes the many strategies exploited to achieve the expression of human transport systems in bacteria, providing a guide to help people who want to deal with this topic.
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Affiliation(s)
- Michele Galluccio
- Unit of Biochemistry and Molecular Biotechnology, Department of Biology, Ecology and Earth Sciences (DiBEST), University of Calabria, Via P. Bucci 4c, Arcavacata di Rende, 87036 Cosenza, Italy; (M.G.); (L.C.); (L.P.); (M.S.)
| | - Lara Console
- Unit of Biochemistry and Molecular Biotechnology, Department of Biology, Ecology and Earth Sciences (DiBEST), University of Calabria, Via P. Bucci 4c, Arcavacata di Rende, 87036 Cosenza, Italy; (M.G.); (L.C.); (L.P.); (M.S.)
| | - Lorena Pochini
- Unit of Biochemistry and Molecular Biotechnology, Department of Biology, Ecology and Earth Sciences (DiBEST), University of Calabria, Via P. Bucci 4c, Arcavacata di Rende, 87036 Cosenza, Italy; (M.G.); (L.C.); (L.P.); (M.S.)
| | - Mariafrancesca Scalise
- Unit of Biochemistry and Molecular Biotechnology, Department of Biology, Ecology and Earth Sciences (DiBEST), University of Calabria, Via P. Bucci 4c, Arcavacata di Rende, 87036 Cosenza, Italy; (M.G.); (L.C.); (L.P.); (M.S.)
| | - Nicola Giangregorio
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnology (IBIOM), National Research Council (CNR), Via Amendola 165/A, 70126 Bari, Italy;
| | - Cesare Indiveri
- Unit of Biochemistry and Molecular Biotechnology, Department of Biology, Ecology and Earth Sciences (DiBEST), University of Calabria, Via P. Bucci 4c, Arcavacata di Rende, 87036 Cosenza, Italy; (M.G.); (L.C.); (L.P.); (M.S.)
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnology (IBIOM), National Research Council (CNR), Via Amendola 165/A, 70126 Bari, Italy;
- Correspondence:
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Ramu Y, Yamakaze J, Zhou Y, Hoshi T, Lu Z. Blocking Kir6.2 channels with SpTx1 potentiates glucose-stimulated insulin secretion from murine pancreatic β cells and lowers blood glucose in diabetic mice. eLife 2022; 11:77026. [PMID: 35212627 PMCID: PMC8880991 DOI: 10.7554/elife.77026] [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: 01/13/2022] [Accepted: 01/26/2022] [Indexed: 11/16/2022] Open
Abstract
ATP-sensitive K+ (KATP) channels in pancreatic β cells are comprised of pore-forming subunits (Kir6.2) and modulatory sulfonylurea receptor subunits (SUR1). The ATP sensitivity of these channels enables them to couple metabolic state to insulin secretion in β cells. Antidiabetic sulfonylureas such as glibenclamide target SUR1 and indirectly suppress Kir6.2 activity. Glibenclamide acts as both a primary and a secondary secretagogue to trigger insulin secretion and potentiate glucose-stimulated insulin secretion, respectively. We tested whether blocking Kir6.2 itself causes the same effects as glibenclamide, and found that the Kir6.2 pore-blocking venom toxin SpTx1 acts as a strong secondary, but not a strong primary, secretagogue. SpTx1 triggered a transient rise of plasma insulin and lowered the elevated blood glucose of diabetic mice overexpressing Kir6.2 but did not affect those of nondiabetic mice. This proof-of-concept study suggests that blocking Kir6.2 may serve as an effective treatment for diabetes and other diseases stemming from KATP hyperactivity that cannot be adequately suppressed with sulfonylureas.
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Affiliation(s)
- Yajamana Ramu
- Department of Physiology, Perelman School of Medicine University of Pennsylvania, Philadelphia, United States
| | - Jayden Yamakaze
- Department of Physiology, Perelman School of Medicine University of Pennsylvania, Philadelphia, United States
| | - Yufeng Zhou
- Department of Physiology, Perelman School of Medicine University of Pennsylvania, Philadelphia, United States
| | - Toshinori Hoshi
- Department of Physiology, Perelman School of Medicine University of Pennsylvania, Philadelphia, United States
| | - Zhe Lu
- Department of Physiology, Perelman School of Medicine University of Pennsylvania, Philadelphia, United States
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Le Ribeuz H, Masson B, Capuano V, Dutheil M, Gooroochurn H, Boët A, Ghigna MR, De Montpreville V, Girerd B, Lambert M, Mercier O, Chung WK, Humbert M, Montani D, Antigny F. SUR1 as a New Therapeutic Target for Pulmonary Arterial Hypertension. Am J Respir Cell Mol Biol 2022; 66:539-554. [PMID: 35175177 DOI: 10.1165/rcmb.2021-0180oc] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Mutations in ABCC8 have been identified in pulmonary arterial hypertension (PAH). ABCC8 encodes SUR1, a regulatory subunit of the ATP-sensitive-potassium channel Kir6.2. However, the pathophysiological role of the SUR1/Kir6.2 channel in PAH is unknown. We hypothesized that activation of SUR1 could be a novel potential target for PAH. We analysed the expression of SUR1/Kir6.2 in the lungs and pulmonary artery (PA) in human PAH or experimental pulmonary hypertension (PH). The contribution of SUR1 in human or rat PA tone was evaluated, and we measured the consequences of in vivo activation of SUR1 in control and PH rats. SUR1 and Kir6.2 protein expression was not reduced in the lungs or human pulmonary arterial endothelial cells and smooth muscle cells (hPAECs and hPASMCs) from PAH or experimentally induced PH. We showed that pharmacological activation of SUR1 by 3 different SUR1 activators (diazoxide, VU0071063, and NN414) leads to PA relaxation. Conversely, the inhibition of SUR1/Kir6.2 channels causes PA constriction. In vivo, long- and short-term activation of SUR1 with diazoxide reversed monocrotaline-induced PH in rats. Additionally, in vivo diazoxide application (short protocol) reduced the severity of PH in chronic-hypoxia rats. Moreover, 3 weeks of diazoxide exposure in control rats had no cardiovascular effects. Finally, in vivo, activation of SUR1 with NN414 reduced monocrotaline-induced PH in rats. In PAH and experimental PH, the expression of SUR1/Kir6.2 was still presented. In vivo pharmacological SUR1 activation by two different molecules alleviated experimental PH, providing proof-of-concept that SUR1 activation should be considered for PAH and evaluated more thoroughly.
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Affiliation(s)
| | | | | | - Mary Dutheil
- INSERM U999, 130034, Le Plessis Robinson, France
| | | | - Angèle Boët
- INSERM U999, 130034, Le Plessis Robinson, France
| | - Maria-Rosa Ghigna
- INSERM UMR_S 999, Hôpital Marie Lannelongue, Le Plessis-Robinson, France.,School of Medicine, Université Paris-Sud / Université Paris Saclay, Le Kremlin-Bicêtre, France
| | | | - Barbara Girerd
- INSERM U999, 130034, pneumolgie, Le Plessis Robinson, France
| | - Mélanie Lambert
- INSERM UMR_S 999, Pulmonary Hypertension: Pathophysiology and Novel Therapies, Hôpital Marie Lannelongue, Le Plessis-Robinson, France
| | - Olaf Mercier
- INSERM U999, 130034, Thoracic Surgery , Le Plessis Robinson, France
| | - Wendy K Chung
- Departments of Pediatrics and Medicine Columbia University, New York, New York, United States
| | - Marc Humbert
- INSERM U999, 130034, Le Plessis Robinson, France
| | - David Montani
- CHU de Bicetre, Service de Pneumologie, Le Kremlin Bicetre, France.,INSERM UMRS 999, Hôpital Marie Lannelongue, Le plessis robinson, France
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Hughson BN. PKG acts in the adult corpora cardiaca to regulate nutrient stress-responsivity through adipokinetic hormone. JOURNAL OF INSECT PHYSIOLOGY 2022; 136:104339. [PMID: 34856210 DOI: 10.1016/j.jinsphys.2021.104339] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 11/22/2021] [Accepted: 11/22/2021] [Indexed: 06/13/2023]
Abstract
In Drosophila melanogaster, the adipokinetic hormone (AKH) is a glucagon-like peptide that acts antagonistically with insulin-like peptides to maintain metabolic homeostasis. AKH is biosynthesized in and secreted from the corpora cardiaca (CC). This report describes a CC-specific role for dg2 - which encodes a cGMP-dependent protein kinase (PKG) - as a regulator of AKH during adulthood. Transcriptional silencing of dg2 during adulthood decreased starvation resistance, increased sucrose responsiveness, and decreased whole body lipid content. PKG protein was localized to CC cell membranes, and starvation caused a significant decrease in CC intracellular AKH content. Strikingly, reduced CC-dg2 expression caused a significant decrease in intracellular AKH content in adults fed ad libitum. This work demonstrated that dysregulation of CC-specific dg2 expression during adult life impaired metabolic homeostasis, and that dg2 acted in the CC to regulate systemic AKH activity.
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Affiliation(s)
- Bryon N Hughson
- Department of Ecology and Evolutionary Biology, University of Toronto, Ontario, Canada; University of Toronto, 27 King's College Circle, Toronto, Ontario M5S 3B2, Canada.
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38
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How Epigenetics Can Enhance Pig Welfare? Animals (Basel) 2021; 12:ani12010032. [PMID: 35011138 PMCID: PMC8749669 DOI: 10.3390/ani12010032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 12/15/2021] [Accepted: 12/21/2021] [Indexed: 12/12/2022] Open
Abstract
Epigenetics works as an interface between the individual and its environment to provide phenotypic plasticity to increase individual adaptation capabilities. Recently, a wide variety of epi-genetic findings have indicated evidence for its application in the development of putative epi-biomarkers of stress in farm animals. The purpose of this study was to evaluate previously reported stress epi-biomarkers in swine and encourage researchers to investigate potential paths for the development of a robust molecular tool for animal welfare certification. In this literature review, we report on the scientific concerns in the swine production chain, the management carried out on the farms, and the potential implications of these practices for the animals' welfare and their epigenome. To assess reported epi-biomarkers, we identified, from previous studies, potentially stress-related genes surrounding epi-biomarkers. With those genes, we carried out a functional enrichment analysis of differentially methylated regions (DMRs) of the DNA of swine subjected to different stress-related conditions (e.g., heat stress, intrauterine insult, and sanitary challenges). We identified potential epi-biomarkers for target analysis, which could be added to the current guidelines and certification schemes to guarantee and certify animal welfare on farms. We believe that this technology may have the power to increase consumers' trust in animal welfare.
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Hughson BN. The Glucagon-Like Adipokinetic Hormone in Drosophila melanogaster - Biosynthesis and Secretion. Front Physiol 2021; 12:710652. [PMID: 35002748 PMCID: PMC8733639 DOI: 10.3389/fphys.2021.710652] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 09/16/2021] [Indexed: 11/13/2022] Open
Abstract
Metabolic homeostasis requires the precise regulation of circulating sugar titers. In mammals, homeostatic control of circulating sugar titers requires the coordinated secretion and systemic activities of glucagon and insulin. Metabolic homeostasis is similarly regulated in Drosophila melanogaster through the glucagon-like adipokinetic hormone (AKH) and the Drosophila insulin-like peptides (DILPs). In flies and mammals, glucagon and AKH are biosynthesized in and secreted from specialized endocrine cells. KATP channels borne on these cells respond to fluctuations in circulating glucose titers and thereby regulate glucagon secretion. The influence of glucagon in the pathogenesis of type 2 diabetes mellitus is now recognized, and a crucial mechanism that regulates glucagon secretion was reported nearly a decade ago. Ongoing efforts to develop D. melanogaster models for metabolic syndrome must build upon this seminal work. These efforts make a critical review of AKH physiology timely. This review focuses on AKH biosynthesis and the regulation of glucose-responsive AKH secretion through changes in CC cell electrical activity. Future directions for AKH research in flies are discussed, including the development of models for hyperglucagonemia and epigenetic inheritance of acquired metabolic traits. Many avenues of AKH physiology remain to be explored and thus present great potential for improving the utility of D. melanogaster in metabolic research.
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Affiliation(s)
- Bryon N. Hughson
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, Canada
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Marinelli I, Fletcher PA, Sherman AS, Satin LS, Bertram R. Symbiosis of Electrical and Metabolic Oscillations in Pancreatic β-Cells. Front Physiol 2021; 12:781581. [PMID: 34925070 PMCID: PMC8682964 DOI: 10.3389/fphys.2021.781581] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 11/08/2021] [Indexed: 11/13/2022] Open
Abstract
Insulin is secreted in a pulsatile pattern, with important physiological ramifications. In pancreatic β-cells, which are the cells that synthesize insulin, insulin exocytosis is elicited by pulses of elevated intracellular Ca2+ initiated by bursts of electrical activity. In parallel with these electrical and Ca2+ oscillations are oscillations in metabolism, and the periods of all of these oscillatory processes are similar. A key question that remains unresolved is whether the electrical oscillations are responsible for the metabolic oscillations via the effects of Ca2+, or whether the metabolic oscillations are responsible for the electrical oscillations due to the effects of ATP on ATP-sensitive ion channels? Mathematical modeling is a useful tool for addressing this and related questions as modeling can aid in the design of well-focused experiments that can test the predictions of particular models and subsequently be used to improve the models in an iterative fashion. In this article, we discuss a recent mathematical model, the Integrated Oscillator Model (IOM), that was the product of many years of development. We use the model to demonstrate that the relationship between calcium and metabolism in beta cells is symbiotic: in some contexts, the electrical oscillations drive the metabolic oscillations, while in other contexts it is the opposite. We provide new insights regarding these results and illustrate that what might at first appear to be contradictory data are actually compatible when viewed holistically with the IOM.
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Affiliation(s)
- Isabella Marinelli
- Centre for Systems Modelling and Quantitative Biomedicine (SMQB), University of Birmingham, Birmingham, United Kingdom
| | - Patrick A Fletcher
- Laboratory of Biological Modeling, National Institutes of Health, Bethesda, MD, United States
| | - Arthur S Sherman
- Laboratory of Biological Modeling, National Institutes of Health, Bethesda, MD, United States
| | - Leslie S Satin
- Department of Pharmacology, Brehm Center for Diabetes Research, University of Michigan Medical School, Ann Arbor, MI, United States
| | - Richard Bertram
- Programs in Neuroscience and Molecular Biophysics, Department of Mathematics, Florida State University, Tallahassee, FL, United States
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Liu M, Jiao Q, Du X, Bi M, Chen X, Jiang H. Potential Crosstalk Between Parkinson's Disease and Energy Metabolism. Aging Dis 2021; 12:2003-2015. [PMID: 34881082 PMCID: PMC8612621 DOI: 10.14336/ad.2021.0422] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 04/22/2021] [Indexed: 01/22/2023] Open
Abstract
Parkinson's disease (PD) is characterized by the accumulation of alpha-synuclein (α-Syn) in the substantia nigra (SN) and the degeneration of nigrostriatal dopaminergic (DAergic) neurons. Some studies have reported that the pathology of PD originates from the gastrointestinal (GI) tract, which also serves as an energy portal, and develops upward along the neural pathway to the central nervous system (CNS), including the dorsal motor nucleus of vagus (DMV), SN, and hypothalamus, which are also involved in energy metabolism control. Therefore, we discuss the alterations of nuclei that regulate energy metabolism in the development of PD. In addition, due to their anti-inflammatory, antiapoptotic and antioxidative roles, metabolism-related peptides are involved in the progression of PD. Furthermore, abnormal glucose and lipid metabolism are common in PD patients and exacerbate the pathological changes in PD. Therefore, in this review, we attempt to explain the correlation between PD and energy metabolism, which may provide possible strategies for PD treatment.
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Affiliation(s)
- Meiqiu Liu
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, School of Basic Medicine, Medical College, Qingdao University, Qingdao, China
| | - Qian Jiao
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, School of Basic Medicine, Medical College, Qingdao University, Qingdao, China
| | - Xixun Du
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, School of Basic Medicine, Medical College, Qingdao University, Qingdao, China
| | - Mingxia Bi
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, School of Basic Medicine, Medical College, Qingdao University, Qingdao, China
| | - Xi Chen
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, School of Basic Medicine, Medical College, Qingdao University, Qingdao, China
| | - Hong Jiang
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, School of Basic Medicine, Medical College, Qingdao University, Qingdao, China
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Abstract
The steadfast advance of the synthetic biology field has enabled scientists to use genetically engineered cells, instead of small molecules or biologics, as the basis for the development of novel therapeutics. Cells endowed with synthetic gene circuits can control the localization, timing and dosage of therapeutic activities in response to specific disease biomarkers and thus represent a powerful new weapon in the fight against disease. Here, we conceptualize how synthetic biology approaches can be applied to programme living cells with therapeutic functions and discuss the advantages that they offer over conventional therapies in terms of flexibility, specificity and predictability, as well as challenges for their development. We present notable advances in the creation of engineered cells that harbour synthetic gene circuits capable of biological sensing and computation of signals derived from intracellular or extracellular biomarkers. We categorize and describe these developments based on the cell scaffold (human or microbial) and the site at which the engineered cell exerts its therapeutic function within its human host. The design of cell-based therapeutics with synthetic biology is a rapidly growing strategy in medicine that holds great promise for the development of effective treatments for a wide variety of human diseases.
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Neonatal Diabetes in Patients Affected by Liang-Wang Syndrome Carrying KCNMA1 Variant p.(Gly375Arg) Suggest a Potential Role of Ca 2+ and Voltage-Activated K + Channel Activity in Human Insulin Secretion. Curr Issues Mol Biol 2021; 43:1036-1042. [PMID: 34563042 PMCID: PMC8928946 DOI: 10.3390/cimb43020073] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 08/21/2021] [Accepted: 08/23/2021] [Indexed: 12/22/2022] Open
Abstract
Liang-Wang syndrome (LIWAS) is a polymalformative syndrome first described in 2019 caused by heterozygous mutation of the KCNMA1 gene encoding the Ca2+ and voltage-activated K+ channel (BKC). The KCNMA1 variant p.(Gly356Arg) abolishes the function of BKC and blocks the generation of K+ current. The phenotype of this variant includes developmental delay, and visceral and connective tissue malformations. So far, only three cases of LWAS have been described, one of which also had neonatal diabetes (ND). We present the case of a newborn affected by LIWAS carrying the p.(Gly375Arg) variant who manifested diabetes in the first week of life. The description of our case strongly increases the frequency of ND in LIWAS patients and suggests a role of BK inactivation in human insulin secretion. The knowledge on the role of BKC in insulin secretion is very poor. Analyzing the possible mechanisms that could explain the association of LIWAS with ND, we speculate that BK inactivation might impair insulin secretion through the alteration of ion-dependent membrane activities and mitochondrial functions in β-cells, as well as the impaired intra-islet vessel reactivity.
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Tang D, Xu J, Li Y, Zhao P, Kong X, Hu H, Liang S, Tang C, Liu Z. Molecular mechanisms of centipede toxin SsTx-4 inhibition of inwardly rectifying potassium channels. J Biol Chem 2021; 297:101076. [PMID: 34391777 PMCID: PMC8413892 DOI: 10.1016/j.jbc.2021.101076] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 08/05/2021] [Accepted: 08/11/2021] [Indexed: 11/29/2022] Open
Abstract
Inwardly rectifying potassium channels (Kirs) are important drug targets, with antagonists for the Kir1.1, Kir4.1, and pancreatic Kir6.2/SUR1 channels being potential drug candidates for treating hypertension, depression, and diabetes, respectively. However, few peptide toxins acting on Kirs are identified and their interacting mechanisms remain largely elusive yet. Herein, we showed that the centipede toxin SsTx-4 potently inhibited the Kir1.1, Kir4.1, and Kir6.2/SUR1 channels with nanomolar to submicromolar affinities and intensively studied the molecular bases for toxin–channel interactions using patch-clamp analysis and site-directed mutations. Other Kirs including Kir2.1 to 2.4, Kir4.2, and Kir7.1 were resistant to SsTx-4 treatment. Moreover, SsTx-4 inhibited the inward and outward currents of Kirs with different potencies, possibly caused by a K+ “knock-off” effect, suggesting the toxin functions as an out pore blocker physically occluding the K+-conducting pathway. This conclusion was further supported by a mutation analysis showing that M137 located in the outer vestibule of the Kir6.2/ΔC26 channel was the key residue mediating interaction with SsTx-4. On the other hand, the molecular determinants within SsTx-4 for binding these Kir channels only partially overlapped, with K13 and F44 being the common key residues. Most importantly, K11A, P15A, and Y16A mutant toxins showed improved affinity and/or selectivity toward Kir6.2, while R12A mutant toxin had increased affinity for Kir4.1. To our knowledge, SsTx-4 is the first characterized peptide toxin with Kir4.1 inhibitory activity. This study provides useful insights for engineering a Kir6.2/SUR1 channel–specific antagonist based on the SsTx-4 template molecule and may be useful in developing new antidiabetic drugs.
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Affiliation(s)
- Dongfang Tang
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha, China; College of Chemistry and Bioengineering, Hunan University of Science and Engineering, Yongzhou, Hunan, China
| | - Jiahui Xu
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha, China
| | - Yinping Li
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha, China
| | - Piao Zhao
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha, China
| | - Xiangjin Kong
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha, China
| | - Haoliang Hu
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha, China
| | - Songping Liang
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha, China
| | - Cheng Tang
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha, China.
| | - Zhonghua Liu
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha, China.
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Tuluc P, Theiner T, Jacobo-Piqueras N, Geisler SM. Role of High Voltage-Gated Ca 2+ Channel Subunits in Pancreatic β-Cell Insulin Release. From Structure to Function. Cells 2021; 10:2004. [PMID: 34440773 PMCID: PMC8393260 DOI: 10.3390/cells10082004] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/27/2021] [Accepted: 08/03/2021] [Indexed: 02/07/2023] Open
Abstract
The pancreatic islets of Langerhans secrete several hormones critical for glucose homeostasis. The β-cells, the major cellular component of the pancreatic islets, secrete insulin, the only hormone capable of lowering the plasma glucose concentration. The counter-regulatory hormone glucagon is secreted by the α-cells while δ-cells secrete somatostatin that via paracrine mechanisms regulates the α- and β-cell activity. These three peptide hormones are packed into secretory granules that are released through exocytosis following a local increase in intracellular Ca2+ concentration. The high voltage-gated Ca2+ channels (HVCCs) occupy a central role in pancreatic hormone release both as a source of Ca2+ required for excitation-secretion coupling as well as a scaffold for the release machinery. HVCCs are multi-protein complexes composed of the main pore-forming transmembrane α1 and the auxiliary intracellular β, extracellular α2δ, and transmembrane γ subunits. Here, we review the current understanding regarding the role of all HVCC subunits expressed in pancreatic β-cell on electrical activity, excitation-secretion coupling, and β-cell mass. The evidence we review was obtained from many seminal studies employing pharmacological approaches as well as genetically modified mouse models. The significance for diabetes in humans is discussed in the context of genetic variations in the genes encoding for the HVCC subunits.
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Affiliation(s)
- Petronel Tuluc
- Centre for Molecular Biosciences, Department of Pharmacology and Toxicology, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria; (T.T.); (N.J.-P.); (S.M.G.)
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Mutated CCDC51 Coding for a Mitochondrial Protein, MITOK Is a Candidate Gene Defect for Autosomal Recessive Rod-Cone Dystrophy. Int J Mol Sci 2021; 22:ijms22157875. [PMID: 34360642 PMCID: PMC8346125 DOI: 10.3390/ijms22157875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 07/05/2021] [Accepted: 07/15/2021] [Indexed: 11/17/2022] Open
Abstract
The purpose of this work was to identify the gene defect underlying a relatively mild rod-cone dystrophy (RCD), lacking disease-causing variants in known genes implicated in inherited retinal disorders (IRD), and provide transcriptomic and immunolocalization data to highlight the best candidate. The DNA of the female patient originating from a consanguineous family revealed no large duplication or deletion, but several large homozygous regions. In one of these, a homozygous frameshift variant, c.244_246delins17 p.(Trp82Valfs*4); predicted to lead to a nonfunctional protein, was identified in CCDC51. CCDC51 encodes the mitochondrial coiled-coil domain containing 51 protein, also called MITOK. MITOK ablation causes mitochondrial dysfunction. Here we show for the first time that CCDC51/MITOK localizes in the retina and more specifically in the inner segments of the photoreceptors, well known to contain mitochondria. Mitochondrial proteins have previously been implicated in IRD, although usually in association with syndromic disease, unlike our present case. Together, our findings add another ultra-rare mutation implicated in non-syndromic IRD, whose pathogenic mechanism in the retina needs to be further elucidated.
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Dobrovolskaite A, Madan M, Pandey V, Altomare DA, Phanstiel O. The discovery of indolone GW5074 during a comprehensive search for non-polyamine-based polyamine transport inhibitors. Int J Biochem Cell Biol 2021; 138:106038. [PMID: 34252566 DOI: 10.1016/j.biocel.2021.106038] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 06/28/2021] [Accepted: 07/05/2021] [Indexed: 01/15/2023]
Abstract
The native polyamines putrescine, spermidine, and spermine are essential for cell development and proliferation. Polyamine levels are often increased in cancer tissues and polyamine depletion is a validated anticancer strategy. Cancer cell growth can be inhibited by the polyamine biosynthesis inhibitor difluoromethylornithine (DFMO), which inhibits ornithine decarboxylase (ODC), the rate-limiting enzyme in the polyamine biosynthesis pathway. Unfortunately, cells treated with DFMO often replenish their polyamine pools by importing polyamines from their environment. Several polyamine-based molecules have been developed to work as polyamine transport inhibitors (PTIs) and have been successfully used in combination with DFMO in several cancer models. Here, we present the first comprehensive search for potential non-polyamine based PTIs that work in human pancreatic cancer cells in vitro. After identifying and testing five different categories of compounds, we have identified the c-RAF inhibitor, GW5074, as a novel non-polyamine based PTI. GW5074 inhibited the uptake of all three native polyamines and a fluorescent-polyamine probe into human pancreatic cancer cells. GW5074 significantly reduced pancreatic cancer cell growth in vitro when treated in combination with DFMO and a rescuing dose of spermidine. Moreover, GW5074 alone reduced tumor growth when tested in a murine pancreatic cancer mouse model in vivo. In summary, GW5074 is a novel non-polyamine-based PTI that potentiates the anticancer activity of DFMO in pancreatic cancers.
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Affiliation(s)
- Aiste Dobrovolskaite
- Department of Medical Education, College of Medicine, University of Central Florida, Orlando, 32827, United States
| | - Meenu Madan
- Department of Medical Education, College of Medicine, University of Central Florida, Orlando, 32827, United States
| | - Veethika Pandey
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, 32827, United States
| | - Deborah A Altomare
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, 32827, United States
| | - Otto Phanstiel
- Department of Medical Education, College of Medicine, University of Central Florida, Orlando, 32827, United States.
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48
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Adams MT, Dwulet JM, Briggs JK, Reissaus CA, Jin E, Szulczewski JM, Lyman MR, Sdao SM, Kravets V, Nimkulrat SD, Ponik SM, Merrins MJ, Mirmira RG, Linnemann AK, Benninger RKP, Blum B. Reduced synchroneity of intra-islet Ca 2+ oscillations in vivo in Robo-deficient β cells. eLife 2021; 10:e61308. [PMID: 34231467 PMCID: PMC8289414 DOI: 10.7554/elife.61308] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 07/06/2021] [Indexed: 12/13/2022] Open
Abstract
The spatial architecture of the islets of Langerhans is hypothesized to facilitate synchronized insulin secretion among β cells, yet testing this in vivo in the intact pancreas is challenging. Robo βKO mice, in which the genes Robo1 and Robo2 are deleted selectively in β cells, provide a unique model of altered islet spatial architecture without loss of β cell differentiation or islet damage from diabetes. Combining Robo βKO mice with intravital microscopy, we show here that Robo βKO islets have reduced synchronized intra-islet Ca2+ oscillations among β cells in vivo. We provide evidence that this loss is not due to a β cell-intrinsic function of Robo, mis-expression or mis-localization of Cx36 gap junctions, or changes in islet vascularization or innervation, suggesting that the islet architecture itself is required for synchronized Ca2+ oscillations. These results have implications for understanding structure-function relationships in the islets during progression to diabetes as well as engineering islets from stem cells.
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Affiliation(s)
- Melissa T Adams
- Department of Cell and Regenerative Biology, University of Wisconsin-MadisonMadisonUnited States
| | - JaeAnn M Dwulet
- Department of Bioengineering, University of Colorado Denver, Anschutz Medical CampusAuroraUnited States
| | - Jennifer K Briggs
- Department of Bioengineering, University of Colorado Denver, Anschutz Medical CampusAuroraUnited States
| | - Christopher A Reissaus
- Herman B Wells Center for Pediatric Research and Center for Diabetes and Metabolic Diseases, Indiana University School of MedicineIndianapolisUnited States
| | - Erli Jin
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Wisconsin-MadisonMadisonUnited States
| | - Joseph M Szulczewski
- Department of Cell and Regenerative Biology, University of Wisconsin-MadisonMadisonUnited States
| | - Melissa R Lyman
- Department of Cell and Regenerative Biology, University of Wisconsin-MadisonMadisonUnited States
| | - Sophia M Sdao
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Wisconsin-MadisonMadisonUnited States
| | - Vira Kravets
- Department of Bioengineering, University of Colorado Denver, Anschutz Medical CampusAuroraUnited States
- Barbara Davis Center for Diabetes, University of Colorado Anschutz Medical CampusAuroraUnited States
| | - Sutichot D Nimkulrat
- Department of Cell and Regenerative Biology, University of Wisconsin-MadisonMadisonUnited States
| | - Suzanne M Ponik
- Department of Cell and Regenerative Biology, University of Wisconsin-MadisonMadisonUnited States
| | - Matthew J Merrins
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Wisconsin-MadisonMadisonUnited States
| | - Raghavendra G Mirmira
- Kovler Diabetes Center and the Department of Medicine, University of ChicagoChicagoUnited States
| | - Amelia K Linnemann
- Herman B Wells Center for Pediatric Research and Center for Diabetes and Metabolic Diseases, Indiana University School of MedicineIndianapolisUnited States
| | - Richard KP Benninger
- Department of Bioengineering, University of Colorado Denver, Anschutz Medical CampusAuroraUnited States
- Barbara Davis Center for Diabetes, University of Colorado Anschutz Medical CampusAuroraUnited States
| | - Barak Blum
- Department of Cell and Regenerative Biology, University of Wisconsin-MadisonMadisonUnited States
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49
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Jackson A, Banka S, Stewart H, Robinson H, Lovell S, Clayton-Smith J. Recurrent KCNT2 missense variants affecting p.Arg190 result in a recognizable phenotype. Am J Med Genet A 2021; 185:3083-3091. [PMID: 34061450 DOI: 10.1002/ajmg.a.62370] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 03/29/2021] [Accepted: 05/05/2021] [Indexed: 12/13/2022]
Abstract
KCNT2 variants resulting in substitutions affecting the Arg190 residue have been shown to cause epileptic encephalopathy and a recognizable facial gestalt. We report two additional individuals with intellectual disability, dysmorphic features, hypertrichosis, macrocephaly and the same de novo KCNT2 missense variants affecting the Arg190 residue as previously described. Notably, neither patient has epilepsy. Homology modeling of these missense variants revealed that they are likely to disrupt the stabilization of a closed channel conformation of KCNT2 resulting in a constitutively open state. This is the first report of pathogenic variants in KCNT2 causing a developmental phenotype without epilepsy.
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Affiliation(s)
- Adam Jackson
- Manchester Centre for Genomic Medicine, Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Siddharth Banka
- Manchester Centre for Genomic Medicine, Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.,Manchester Centre for Genomic Medicine, St Mary's Hospital, Manchester University NHS Foundation Trust, Health Innovation Manchester, Manchester, UK
| | - Helen Stewart
- Department of Clinical Genetics, Oxford Centre for Genomic Medicine, Oxford Radcliffe Hospitals NHS Trust, Nuffield Orthopaedic Hospital, Oxford, UK
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- Genomics England, London, UK
| | - Hannah Robinson
- Department of Peninsula Clinical Genetics, Exeter Genomics Laboratory, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - Simon Lovell
- Division of Evolution and Genomic Sciences, School of Biological Sciences, University of Manchester, Manchester, UK
| | - Jill Clayton-Smith
- Manchester Centre for Genomic Medicine, Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.,Manchester Centre for Genomic Medicine, St Mary's Hospital, Manchester University NHS Foundation Trust, Health Innovation Manchester, Manchester, UK
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50
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Saadati M, Jamali Y. The effects of beta-cell mass and function, intercellular coupling, and islet synchrony on [Formula: see text] dynamics. Sci Rep 2021; 11:10268. [PMID: 33986325 PMCID: PMC8119479 DOI: 10.1038/s41598-021-89333-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Accepted: 04/26/2021] [Indexed: 11/30/2022] Open
Abstract
Type 2 diabetes (T2D) is a challenging metabolic disorder characterized by a substantial loss of [Formula: see text]-cell mass and alteration of [Formula: see text]-cell function in the islets of Langerhans, disrupting insulin secretion and glucose homeostasis. The mechanisms for deficiency in [Formula: see text]-cell mass and function during the hyperglycemia development and T2D pathogenesis are complex. To study the relative contribution of [Formula: see text]-cell mass to [Formula: see text]-cell function in T2D, we make use of a comprehensive electrophysiological model of human [Formula: see text]-cell clusters. We find that defect in [Formula: see text]-cell mass causes a functional decline in single [Formula: see text]-cell, impairment in intra-islet synchrony, and changes in the form of oscillatory patterns of membrane potential and intracellular [Formula: see text] concentration, which can lead to changes in insulin secretion dynamics and in insulin levels. The model demonstrates a good correspondence between suppression of synchronizing electrical activity and published experimental measurements. We then compare the role of gap junction-mediated electrical coupling with both [Formula: see text]-cell synchronization and metabolic coupling in the behavior of [Formula: see text] concentration dynamics within human islets. Our results indicate that inter-[Formula: see text]-cellular electrical coupling depicts a more important factor in shaping the physiological regulation of islet function and in human T2D. We further predict that varying the whole-cell conductance of delayed rectifier [Formula: see text] channels modifies oscillatory activity patterns of [Formula: see text]-cell population lacking intercellular coupling, which significantly affect [Formula: see text] concentration and insulin secretion.
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Affiliation(s)
- Maryam Saadati
- Biomathematics Laboratory, Department of Applied Mathematics, School of Mathematical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Yousef Jamali
- Biomathematics Laboratory, Department of Applied Mathematics, School of Mathematical Sciences, Tarbiat Modares University, Tehran, Iran
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