1
|
Hymer WC, Kraemer WJ. Resistance exercise stress: theoretical mechanisms for growth hormone processing and release from the anterior pituitary somatotroph. Eur J Appl Physiol 2023; 123:1867-1878. [PMID: 37421488 DOI: 10.1007/s00421-023-05263-8] [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: 03/11/2023] [Accepted: 06/15/2023] [Indexed: 07/10/2023]
Abstract
Heavy resistance exercise (HRE) is the most effective method for inducing muscular hypertrophy and stimulating anabolic hormones, including growth hormone, into the blood. In this review, we explore possible mechanisms within the GH secretory pathway of the pituitary somatotroph, which are likely to modulate the flow of hormone synthesis and packaging as it is processed prior to exocytosis. Special emphasis is placed on the secretory granule and its possible role as a signaling hub. We also review data that summarize how HRE affects the quality and quantity of the secreted hormone. Finally, these pathway mechanisms are considered in the context of heterogeneity of the somatotroph population in the anterior pituitary.
Collapse
Affiliation(s)
- Wesley C Hymer
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA
| | - William J Kraemer
- Department of Human Sciences, The Ohio State University, Columbus, OH, 43802, USA.
- Department of Kinesiology, University of Connecticut, Storrs, CT, USA.
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, CT, USA.
- School of Medical and Health Sciences, Edith Cowan University, Perth, Australia.
| |
Collapse
|
2
|
Jiráček J, Selicharová I, Žáková L. Mutations at hypothetical binding site 2 in insulin and insulin-like growth factors 1 and 2. VITAMINS AND HORMONES 2023; 123:187-230. [PMID: 37717985 DOI: 10.1016/bs.vh.2023.01.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/05/2023]
Abstract
Elucidating how insulin and the related insulin-like growth factors 1 and 2 (IGF-1 and IGF-2) bind to their cellular receptors (IR and IGF-1R) and how the receptors are activated has been the holy grail for generations of scientists. However, deciphering the 3D structure of tyrosine kinase receptors and their hormone-bound complexes has been complicated by the flexible and dimeric nature of the receptors and the dynamic nature of their interaction with hormones. Therefore, mutagenesis of hormones and kinetic studies first became an important tool for studying receptor interactions. It was suggested that hormones could bind to receptors through two binding sites on the hormone surface called site 1 and site 2. A breakthrough in knowledge came with the solution of cryoelectron microscopy (cryoEM) structures of hormone-receptor complexes. In this chapter, we document in detail the mutagenesis of insulin, IGF-1, and IGF-2 with emphasis on modifications of the hypothetical binding site 2 in the hormones, and we discuss the results of structure-activity studies in light of recent cryoEM structures of hormone complexes with IR and IGF-1R.
Collapse
Affiliation(s)
- Jiří Jiráček
- From Institute of Organic Chemistry and Biochemistry, The Czech Academy of Sciences, Prague, Czech Republic.
| | - Irena Selicharová
- From Institute of Organic Chemistry and Biochemistry, The Czech Academy of Sciences, Prague, Czech Republic
| | - Lenka Žáková
- From Institute of Organic Chemistry and Biochemistry, The Czech Academy of Sciences, Prague, Czech Republic
| |
Collapse
|
3
|
Asai S, Moravcová J, Žáková L, Selicharová I, Hadravová R, Brzozowski AM, Nováček J, Jiráček J. Characterization of insulin crystalline form in isolated β-cell secretory granules. Open Biol 2022; 12:220322. [PMID: 36541100 PMCID: PMC9768635 DOI: 10.1098/rsob.220322] [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] [Indexed: 12/24/2022] Open
Abstract
Insulin is stored in vivo inside the pancreatic β-cell insulin secretory granules. In vitro studies have led to an assumption that high insulin and Zn2+ concentrations inside the pancreatic β-cell insulin secretory granules should promote insulin crystalline state in the form of Zn2+-stabilized hexamers. Electron microscopic images of thin sections of the pancreatic β-cells often show a dense, regular pattern core, suggesting the presence of insulin crystals. However, the structural features of the storage forms of insulin in native preparations of secretory granules are unknown, because of their small size, fragile character and difficult handling. We isolated and investigated the secretory granules from MIN6 cells under near-native conditions, using cryo-electron microscopic (Cryo-EM) techniques. The analysis of these data from multiple intra-granular crystals revealed two different rhomboidal crystal lattices. The minor lattice has unit cell parameters (a ≃ b ≃ 84.0 Å, c ≃ 35.2 Å), similar to in vitro crystallized human 4Zn2+-insulin hexamer, whereas the largely prevalent unit cell has more than double c-axis (a ≃ b ≃ c ≃ 96.5 Å) that probably corresponds to two or three insulin hexamers in the asymmetric unit. Our experimental data show that insulin can be present in pancreatic MIN6 cell granules in a microcrystalline form, probably consisting of 4Zn2+-hexamers of this hormone.
Collapse
Affiliation(s)
- Seiya Asai
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 11610 Prague 6, Czech Republic,Department of Biochemistry, Faculty of Science, Charles University, 12840 Prague 2, Czech Republic
| | - Jana Moravcová
- CEITEC, Cryo-Electron Microscopy and Tomography Core Facility, Masaryk University, Kamenice 5, 62500 Bohunice, Czech Republic
| | - Lenka Žáková
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 11610 Prague 6, Czech Republic
| | - Irena Selicharová
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 11610 Prague 6, Czech Republic
| | - Romana Hadravová
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 11610 Prague 6, Czech Republic
| | - Andrzej Marek Brzozowski
- York Structural Biology Laboratory, Department of Chemistry, University of York, Heslington, York YO10 5DD, UK
| | - Jiří Nováček
- CEITEC, Cryo-Electron Microscopy and Tomography Core Facility, Masaryk University, Kamenice 5, 62500 Bohunice, Czech Republic
| | - Jiří Jiráček
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 11610 Prague 6, Czech Republic
| |
Collapse
|
4
|
Pizzo F, Mangione MR, Librizzi F, Manno M, Martorana V, Noto R, Vilasi S. The Possible Role of the Type I Chaperonins in Human Insulin Self-Association. Life (Basel) 2022; 12:life12030448. [PMID: 35330199 PMCID: PMC8949404 DOI: 10.3390/life12030448] [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: 02/17/2022] [Revised: 03/11/2022] [Accepted: 03/16/2022] [Indexed: 11/16/2022] Open
Abstract
Insulin is a hormone that attends to energy metabolism by regulating glucose levels in the bloodstream. It is synthesised within pancreas beta-cells where, before being released into the serum, it is stored in granules as hexamers coordinated by Zn2+ and further packaged in microcrystalline structures. The group I chaperonin cpn60, known for its assembly-assisting function, is present, together with its cochaperonin cpn10, at each step of the insulin secretory pathway. However, the exact function of the heat shock protein in insulin biosynthesis and processing is still far from being understood. Here we explore the possibility that the molecular machine cpn60/cpn10 could have a role in insulin hexameric assembly and its further crystallization. Moreover, we also evaluate their potential protective effect in pathological insulin aggregation. The experiments performed with the cpn60 bacterial homologue, GroEL, in complex with its cochaperonin GroES, by using spectroscopic methods, microscopy and hydrodynamic techniques, reveal that the chaperonins in vitro favour insulin hexameric organisation and inhibit its aberrant aggregation. These results provide new details in the field of insulin assembly and its related disorders.
Collapse
|
5
|
Garvey RW, Lacivita E, Niso M, Duszyńska B, Harris PE, Leopoldo M. Design, synthesis, and characterization of a novel fluoroprobe for live human islet cell imaging of serotonin 5-HT1A receptor. ChemMedChem 2022; 17:e202100759. [PMID: 35286016 DOI: 10.1002/cmdc.202100759] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 03/08/2022] [Indexed: 11/09/2022]
Abstract
Mounting evidence suggests that the serotonin system serves in signal transmission to regulate insulin secretion in pancreatic islets of Langerhans. Among the 5-HT receptor subtype found in pancreatic islets, serotonin receptor 1A (5-HT 1A ) demonstrates a unique ability to inhibit beta-cell insulin secretion. We report on the design, synthesis, and characterization of two novel fluorescent probes for the 5-HT 1A receptor. The compounds were prepared by conjugating the scaffold of the 5-HT 1A receptor agonist 8-OH-DPAT with two fluorophores suitable for live-cells imaging. Compound 5a showed a high affinity for the 5-HT 1A receptor ( K i = 1.8 nM). Fluoroprobe 5a was able to label the 5-HT 1A receptor in pancreatic islet cell cultures in a selective manner, as the fluorescence emission was significantly attenuated by co-administration of the 5-HT 1A receptor antagonist WAY-100635. Thus, fluoroprobe 5a showed useful properties to further characterize this unique receptor's role.
Collapse
Affiliation(s)
- Robert W Garvey
- Columbia University, Division of Endocrinology, Department of Medicine, UNITED STATES
| | - Enza Lacivita
- Universita' degli Studi di Bari, Dipartimento di Farmacia-Scienze del Farmaco, Via Orabona, 4, 70125, Bari, ITALY
| | - Mauro Niso
- Università degli Studi di Bari Aldo Moro: Universita degli Studi di Bari Aldo Moro, Dipartimento di Farmacia -Scienze del Farmaco, Via Orabona, 4, 70125, Bari, ITALY
| | - Beata Duszyńska
- Institute of Pharmacology of the Polish Academy of Sciences: Instytut Farmakologii im Jerzego Maja Polskiej Akademii Nauk, Department of Medicinal Chemistry, Smetna, 12, 31-343, Krakow, POLAND
| | - Paul E Harris
- Columbia University, Division of Endocrinology, Department of Medicine, UNITED STATES
| | - Marcello Leopoldo
- Università degli Studi di Bari Aldo Moro: Universita degli Studi di Bari Aldo Moro, Dipartimento di Farmacia-Scienze del Farmaco, Via Orabona, 4, 70125, Bari, ITALY
| |
Collapse
|
6
|
Gorai B, Vashisth H. Structures and interactions of insulin-like peptides from cone snail venom. Proteins 2022; 90:680-690. [PMID: 34661928 PMCID: PMC8816879 DOI: 10.1002/prot.26265] [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: 07/21/2021] [Revised: 09/27/2021] [Accepted: 10/12/2021] [Indexed: 12/19/2022]
Abstract
The venomous insulin-like peptides released by certain cone snails stimulate hypoglycemic shock to immobilize fish and catch the prey. Compared to human insulin (hIns), the cone snail insulins (Con-Ins) are typically monomeric and shorter in sequence, yet they exhibit moderate hIns-like biological activity. We have modeled six variants of Con-Ins (G3, K1, K2, T1A, T1B, and T2) and carried out explicit-solvent molecular dynamics (MD) simulations of eight types of insulins, two with known structures (hIns and Con-Ins-G1) and six Con-Ins with modeled structures, to characterize key residues of each insulin that interact with the truncated human insulin receptor (μIR). We show that each insulin/μIR complex is stable during explicit-solvent MD simulations and hIns interactions indicate the highest affinity for the "site 1" of IR. The residue contact maps reveal that each insulin preferably interacts with the αCT peptide than the L1 domain of IR. Through analysis of the average nonbonded interaction energy contribution of every residue of each insulin for the μIR, we probe the residues establishing favorable interactions with the receptor. We compared the interaction energy of each residue of every Con-Ins to the μIR and observed that γ-carboxylated glutamate (Gla), His, Thr, Tyr, Tyr/His, and Asn in Con-Ins are favorable substitutions for GluA4, AsnA21, ValB12, LeuB15, GlyB20, and ArgB22 in hIns, respectively. The identified insulin analogs, although lacking the last eight residues of the B-chain of hIns, bind strongly to μIR. Our findings are potentially useful in designing potent fast-acting therapeutic insulin.
Collapse
Affiliation(s)
- Biswajit Gorai
- Department of Chemical Engineering, University of New Hampshire, Durham, NH 03824, USA
| | - Harish Vashisth
- Department of Chemical Engineering, University of New Hampshire, Durham, NH 03824, USA
| |
Collapse
|
7
|
Gorai B, Vashisth H. Progress in Simulation Studies of Insulin Structure and Function. Front Endocrinol (Lausanne) 2022; 13:908724. [PMID: 35795141 PMCID: PMC9252437 DOI: 10.3389/fendo.2022.908724] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 04/28/2022] [Indexed: 01/02/2023] Open
Abstract
Insulin is a peptide hormone known for chiefly regulating glucose level in blood among several other metabolic processes. Insulin remains the most effective drug for treating diabetes mellitus. Insulin is synthesized in the pancreatic β-cells where it exists in a compact hexameric architecture although its biologically active form is monomeric. Insulin exhibits a sequence of conformational variations during the transition from the hexamer state to its biologically-active monomer state. The structural transitions and the mechanism of action of insulin have been investigated using several experimental and computational methods. This review primarily highlights the contributions of molecular dynamics (MD) simulations in elucidating the atomic-level details of conformational dynamics in insulin, where the structure of the hormone has been probed as a monomer, dimer, and hexamer. The effect of solvent, pH, temperature, and pressure have been probed at the microscopic scale. Given the focus of this review on the structure of the hormone, simulation studies involving interactions between the hormone and its receptor are only briefly highlighted, and studies on other related peptides (e.g., insulin-like growth factors) are not discussed. However, the review highlights conformational dynamics underlying the activities of reported insulin analogs and mimetics. The future prospects for computational methods in developing promising synthetic insulin analogs are also briefly highlighted.
Collapse
|
8
|
Duboué-Dijon E, Hénin J. Building intuition for binding free energy calculations: Bound state definition, restraints, and symmetry. J Chem Phys 2021; 154:204101. [PMID: 34241173 DOI: 10.1063/5.0046853] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The theory behind computation of absolute binding free energies using explicit-solvent molecular simulations is well-established, yet somewhat complex, with counter-intuitive aspects. This leads to frequent frustration, common misconceptions, and sometimes erroneous numerical treatment. To improve this, we present the main practically relevant segments of the theory with constant reference to physical intuition. We pinpoint the role of the implicit or explicit definition of the bound state (or the binding site) to make a robust link between an experimental measurement and a computational result. We clarify the role of symmetry and discuss cases where symmetry number corrections have been misinterpreted. In particular, we argue that symmetry corrections as classically presented are a source of confusion and could be advantageously replaced by restraint free energy contributions. We establish that contrary to a common intuition, partial or missing sampling of some modes of symmetric bound states does not affect the calculated decoupling free energies. Finally, we review these questions and pitfalls in the context of a few common practical situations: binding to a symmetric receptor (equivalent binding sites), binding of a symmetric ligand (equivalent poses), and formation of a symmetric complex, in the case of homodimerization.
Collapse
Affiliation(s)
- E Duboué-Dijon
- CNRS, Université de Paris, UPR 9080, Laboratoire de Biochimie Théorique, 13 rue Pierre et Marie Curie, 75005 Paris, France
| | - J Hénin
- CNRS, Université de Paris, UPR 9080, Laboratoire de Biochimie Théorique, 13 rue Pierre et Marie Curie, 75005 Paris, France
| |
Collapse
|
9
|
Asai S, Žáková L, Selicharová I, Marek A, Jiráček J. A radioligand receptor binding assay for measuring of insulin secreted by MIN6 cells after stimulation with glucose, arginine, ornithine, dopamine, and serotonin. Anal Bioanal Chem 2021; 413:4531-4543. [PMID: 34050775 DOI: 10.1007/s00216-021-03423-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 05/07/2021] [Accepted: 05/20/2021] [Indexed: 12/31/2022]
Abstract
We adapted a radioligand receptor binding assay for measuring insulin levels in unknown samples. The assay enables rapid and accurate determination of insulin concentrations in experimental samples, such as from insulin-secreting cells. The principle of the method is based on the binding competition of insulin in a measured sample with a radiolabeled insulin for insulin receptor (IR) in IM-9 cells. Both key components, radiolabeled insulin and IM-9 cells, are commercially available. The IR binding assay was used to determine unknown amounts of insulin secreted by MIN6 β cell line after stimulation with glucose, arginine, ornithine, dopamine, and serotonin. The experimental data obtained by the IR binding assay were compared to the results determined by RIA kits and both methods showed a very good agreement of results. We observed the stimulation of glucose-induced insulin secretion from MIN6 cells by arginine, weaker stimulation by ornithine, but inhibitory effects of dopamine. Serotonin effects were either stimulatory or inhibitory, depending on the concentration of serotonin used. The results will require further investigation. The study also clearly revealed advantages of the IR binding assay that allows the measuring of a higher throughput of measured samples, with a broader range of concentrations than in the case of RIA kits. The IR binding assay can provide an alternative to standard RIA and ELISA assays for the determination of insulin levels in experimental samples and can be especially useful in scientific laboratories studying insulin production and secretion by β cells and searching for new modulators of insulin secretion.
Collapse
Affiliation(s)
- Seiya Asai
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 116 10, Prague 6, Czech Republic
- Department of Biochemistry, Faculty of Science, Charles University, 12840, Prague 2, Czech Republic
| | - Lenka Žáková
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 116 10, Prague 6, Czech Republic
| | - Irena Selicharová
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 116 10, Prague 6, Czech Republic
| | - Aleš Marek
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 116 10, Prague 6, Czech Republic
| | - Jiří Jiráček
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 116 10, Prague 6, Czech Republic.
| |
Collapse
|
10
|
Jacobs FJF, Venter GJS, Fourie E, Kroon RE, Brink A. Substitution reactivity and structural variability induced by tryptamine on the biomimetic rhenium tricarbonyl complex. RSC Adv 2021; 11:24443-24455. [PMID: 35479015 PMCID: PMC9036643 DOI: 10.1039/d1ra03750a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Accepted: 07/02/2021] [Indexed: 01/28/2023] Open
Abstract
A series of seven fac-[Re(CO)3(5Me-Sal-Trypt)(L)] complexes containing tryptamine on the N,O 5-methyl-salicylidene bidentate ligand backbone and where L is MeOH, Py, Imi, DMAP, PPh3 coordinated to the 6th position have been studied, including the formation of a dinuclear Re2 cluster. The crystallographic solid state structures show marked similarity in structural tendency, in particular the rigidity of the Re core and the hydrogen bond interactions similar to those found in protein structures. The rates of formation and stability of the complexes were evaluated by rapid time-resolved stopped-flow techniques and the methanol substitution reaction indicates the significant activation induced by the use of the N,O salicylidene bidentate ligand as manifested by the second-order rate constants for the entering nucleophiles. Both linear and limiting kinetics were observed and a systematic evaluation of the kinetics is reported clearly indicating an interchange type of intimate mechanism for the methanol substitution. The anticancer activity of compounds 1–7 was tested on HeLa cells and it was found that all compounds showed similar cytotoxicity where solubility allowed. IC50-values between ca. 11 and 22 μM indicate that some cytotoxicity resides most likely on the salicylidene–tryptamine ligand. The photoluminescence of the seven complexes is similar in maximum emission wavelength with little variation despite the broad range of ligands coordinated to the 6th position on the metal centre. The biomimetic tryptamine rhenium tricarbonyl complex shows rapid substitution reactivity on the 6th position as well as cytotoxicity and photoluminescence capability induced by the salicylidene bidentate ligand.![]()
Collapse
Affiliation(s)
| | | | - Eleanor Fourie
- Department of Chemistry
- University of the Free State
- Bloemfontein 9300
- South Africa
| | - Robin E. Kroon
- Department of Physics
- University of the Free State
- Bloemfontein 9300
- South Africa
| | - Alice Brink
- Department of Chemistry
- University of the Free State
- Bloemfontein 9300
- South Africa
| |
Collapse
|
11
|
Johansson E, Wu X, Yu B, Yang Z, Cao Z, Wiberg C, Jeppesen CB, Poulsen F. Insulin binding to the analytical antibody sandwich pair OXI-005 and HUI-018: Epitope mapping and binding properties. Protein Sci 2020; 30:485-496. [PMID: 33277949 DOI: 10.1002/pro.4009] [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: 12/02/2020] [Accepted: 12/04/2020] [Indexed: 11/08/2022]
Abstract
The insulin epitopes for two monoclonal antibodies (mAbs), OXI-005 and HUI-018, commonly used in combination for insulin concentration determination in sandwich assays, were determined using X-ray crystallography. The crystal structure of the HUI-018 Fab in complex with human insulin (HI) was determined and OXI-005 Fab crystal structures were determined in complex with HI and porcine insulin (PI) as well as on its own. The OXI-005 epitope comprises insulin residues 1,3,4,19-21 (A-chain) and 25-30 (B-chain) and for HUI-018 residues 7,8,10-14,17 (A-chain) and 5-7, 10, 14 (B-chain). The areas of insulin involved in interactions with the mAb are 20% (OXI-005) and 24% (HUI-018) of the total insulin surface. Based on the Fab complex crystal structures with the insulins a molecular model for simultaneous binding of the Fabs to PI was built and this model was validated by small angle X-ray scattering measurements for the ternary complex. The epitopes for the mAbs on insulin were found well separated from each other as expected from luminiscent oxygen channeling immunoassay results for different insulins (HI, PI, bovine insulin, DesB30 HI, insulin glargine, insulin lispro). The affinities of the OXI-005 and HUI-018 Fabs for HI, PI, and DesB30 HI were determined using surface plasmon resonance. The KD s were found to be in the range of 1-4 nM for the HUI-018 Fab, while more different for the OXI-005 Fab (50 nM for HI, 20 nM for PI and 400 nM for DesB30 HI) supporting the importance of residue B30 for binding to OXI-005.
Collapse
Affiliation(s)
| | - Xiaoai Wu
- Novo Nordisk Research Centre China, Beijing, Changping District, China
| | - Bingke Yu
- Novo Nordisk Research Centre China, Beijing, Changping District, China
| | - Zhiru Yang
- Novo Nordisk Research Centre China, Beijing, Changping District, China
| | - Zheng Cao
- Novo Nordisk Research Centre China, Beijing, Changping District, China
| | | | | | | |
Collapse
|
12
|
Wang Y, Adeoye DI, Ogunkunle EO, Wei IA, Filla RT, Roper MG. Affinity Capillary Electrophoresis: A Critical Review of the Literature from 2018 to 2020. Anal Chem 2020; 93:295-310. [DOI: 10.1021/acs.analchem.0c04526] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Yao Wang
- Department of Chemistry and Biochemistry, Florida State University, 95 Chieftain Way, Tallahassee, Florida 32306, United States
| | - Damilola I. Adeoye
- Department of Chemistry and Biochemistry, Florida State University, 95 Chieftain Way, Tallahassee, Florida 32306, United States
| | - Emmanuel O. Ogunkunle
- Department of Chemistry and Biochemistry, Florida State University, 95 Chieftain Way, Tallahassee, Florida 32306, United States
| | - I-An Wei
- Department of Chemistry and Biochemistry, Florida State University, 95 Chieftain Way, Tallahassee, Florida 32306, United States
| | - Robert T. Filla
- Department of Chemistry and Biochemistry, Florida State University, 95 Chieftain Way, Tallahassee, Florida 32306, United States
| | - Michael G. Roper
- Department of Chemistry and Biochemistry, Florida State University, 95 Chieftain Way, Tallahassee, Florida 32306, United States
| |
Collapse
|
13
|
Dzianová P, Asai S, Chrudinová M, Kosinová L, Potalitsyn P, Šácha P, Hadravová R, Selicharová I, Kříž J, Turkenburg JP, Brzozowski AM, Jiráček J, Žáková L. The efficiency of insulin production and its content in insulin-expressing model β-cells correlate with their Zn 2+ levels. Open Biol 2020; 10:200137. [PMID: 33081637 PMCID: PMC7653362 DOI: 10.1098/rsob.200137] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 09/24/2020] [Indexed: 12/29/2022] Open
Abstract
Insulin is produced and stored inside the pancreatic β-cell secretory granules, where it is assumed to form Zn2+-stabilized oligomers. However, the actual storage forms of this hormone and the impact of zinc ions on insulin production in vivo are not known. Our initial X-ray fluorescence experiment on granules from native Langerhans islets and insulinoma-derived INS-1E cells revealed a considerable difference in the zinc content. This led our further investigation to evaluate the impact of the intra-granular Zn2+ levels on the production and storage of insulin in different model β-cells. Here, we systematically compared zinc and insulin contents in the permanent INS-1E and BRIN-BD11 β-cells and in the native rat pancreatic islets by flow cytometry, confocal microscopy, immunoblotting, specific messenger RNA (mRNA) and total insulin analysis. These studies revealed an impaired insulin production in the permanent β-cell lines with the diminished intracellular zinc content. The drop in insulin and Zn2+ levels was paralleled by a lower expression of ZnT8 zinc transporter mRNA and hampered proinsulin processing/folding in both permanent cell lines. To summarize, we showed that the disruption of zinc homeostasis in the model β-cells correlated with their impaired insulin and ZnT8 production. This indicates a need for in-depth fundamental research about the role of zinc in insulin production and storage.
Collapse
Affiliation(s)
- Petra Dzianová
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 116 10 Prague 6, Czech Republic
| | - Seiya Asai
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 116 10 Prague 6, Czech Republic
- Department of Biochemistry, Faculty of Science, Charles University, 12840 Prague 2, Czech Republic
| | - Martina Chrudinová
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 116 10 Prague 6, Czech Republic
| | - Lucie Kosinová
- Laboratory of Pancreatic Islets, Institute for Clinical and Experimental Medicine, Videnska 1958/9, 140 21 Prague, Czech Republic
| | - Pavlo Potalitsyn
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 116 10 Prague 6, Czech Republic
- Department of Biochemistry, Faculty of Science, Charles University, 12840 Prague 2, Czech Republic
| | - Pavel Šácha
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 116 10 Prague 6, Czech Republic
| | - Romana Hadravová
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 116 10 Prague 6, Czech Republic
| | - Irena Selicharová
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 116 10 Prague 6, Czech Republic
| | - Jan Kříž
- Laboratory of Pancreatic Islets, Institute for Clinical and Experimental Medicine, Videnska 1958/9, 140 21 Prague, Czech Republic
| | - Johan P. Turkenburg
- York Structural Biology Laboratory, Department of Chemistry, University of York, Heslington, York YO10 5DD, United Kingdom
| | - Andrzej Marek Brzozowski
- York Structural Biology Laboratory, Department of Chemistry, University of York, Heslington, York YO10 5DD, United Kingdom
| | - Jiří Jiráček
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 116 10 Prague 6, Czech Republic
| | - Lenka Žáková
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 116 10 Prague 6, Czech Republic
| |
Collapse
|
14
|
Šolínová V, Žáková L, Jiráček J, Kašička V. Pressure assisted partial filling affinity capillary electrophoresis employed for determination of binding constants of human insulin hexamer complexes with serotonin, dopamine, arginine, and phenol. Anal Chim Acta 2019; 1052:170-178. [DOI: 10.1016/j.aca.2018.11.026] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 11/10/2018] [Accepted: 11/12/2018] [Indexed: 11/30/2022]
|
15
|
Pecic S, Milosavic N, Rayat G, Maffei A, Harris PE. A novel optical tracer for VMAT2 applied to live cell measurements of vesicle maturation in cultured human β-cells. Sci Rep 2019; 9:5403. [PMID: 30932004 PMCID: PMC6443945 DOI: 10.1038/s41598-019-41891-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Accepted: 03/19/2019] [Indexed: 02/03/2023] Open
Abstract
The islet β-cells integrate external signals to modulate insulin secretion to better regulate blood glucose levels during periods of changing metabolic demand. The vesicular monoamine transporter type 2 (VMAT2), an important regulator of CNS neurotransmission, has an analogous role in the endocrine pancreas as a key control point of insulin secretion, with additional roles in regulating β-cell differentiation and proliferation. Here we report on the synthesis and biological characterisation of a fluorescent ligand for VMAT2 suitable for live cell imaging. Staining for VMAT2 and dopamine in live β-cell cultures show colocalisation in specific vesicles and reveal a heterogeneous population with respect to cell size, shape, vesicle number, size, and contents. Staining for VMAT2 and zinc ion, as a surrogate for insulin, reveals a wide range of vesicle sizes. Immunohistochemistry shows larger β-cell vesicles enriched for proinsulin, whereas smaller vesicles predominantly contain the processed mature insulin. In β-cell cultures obtained from nondiabetic donors, incubation at non-stimulatory glucose concentrations promotes a shift in vesicle diameter towards the more mature insulin vesicles at the expense of the larger immature insulin secretory vesicle population. We anticipate that this probe will be a useful reagent to identify living β-cells within complex mixtures for further manipulation and characterisation.
Collapse
Affiliation(s)
- Stevan Pecic
- Department of Chemistry and Biochemistry, California State University, Fullerton, California, USA
| | - Nenad Milosavic
- Division of Experimental Therapeutics, Department of Medicine, Columbia University Medical Centre, New York, New York, USA
| | - Gina Rayat
- Alberta Diabetes Institute, Ray Rajotte Surgical-Medical Research Institute, Department of Surgery, University of Alberta, Edmonton, AB, T6G 2E1, Canada
| | - Antonella Maffei
- Division of Endocrinology, Department of Medicine and Naomi Berrie Diabetes Center, Columbia University Medical Centre, New York, New York, USA
| | - Paul E Harris
- Division of Endocrinology, Department of Medicine and Naomi Berrie Diabetes Center, Columbia University Medical Centre, New York, New York, USA.
| |
Collapse
|
16
|
Korner J, Cline GW, Slifstein M, Barba P, Rayat GR, Febres G, Leibel RL, Maffei A, Harris PE. A role for foregut tyrosine metabolism in glucose tolerance. Mol Metab 2019; 23:37-50. [PMID: 30876866 PMCID: PMC6479665 DOI: 10.1016/j.molmet.2019.02.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 02/14/2019] [Accepted: 02/24/2019] [Indexed: 01/13/2023] Open
Abstract
Objective We hypothesized that DA and L-DOPA derived from nutritional tyrosine and the resultant observed postprandial plasma excursions of L-DOPA and DA might affect glucose tolerance via their ability to be taken-up by beta cells and inhibit glucose-stimulated β-cell insulin secretion. Methods To investigate a possible circuit between meal-stimulated 3,4-dihydroxy-L-phenylalanine (L-DOPA) and dopamine (DA) production in the GI tract and pancreatic β-cells, we: 1) mapped GI mucosal expression of tyrosine hydroxylase (TH) and aromatic amino acid decarboxylase (AADC); 2) measured L-DOPA and DA content of GI mucosal tissues following meal challenges with different L-tyrosine (TYR) content, 3) determined whether meal TYR content impacts plasma insulin and glucose excursions; and 4) characterized postprandial plasma excursions of L-DOPA and DA in response to meal tyrosine content in rodents and a population of bariatric surgery patients. Next, we characterized: 1) the metabolic transformation of TYR and L-DOPA into DA in vitro using purified islet tissue; 2) the metabolic transformation of orally administrated stable isotope labeled TYR into pancreatic DA, and 3) using a nuclear medicine technique, we studied endocrine beta cells in situ release and binding of DA in response to a glucose challenge. Results We demonstrate in rodents that intestinal content and circulatory concentrations L-DOPA and DA, plasma glucose and insulin are responsive to the tyrosine (TYR) content of a test meal. Intestinal expression of two enzymes, Tyrosine hydroxylase (TH) and Aromatic Amino acid Decarboxylase (AADC), essential to the transformation of TYR to DA was mapped and the metabolism of metabolism of TYR to DA was traced in human islets and a rodent beta cell line in vitro and from gut to the pancreas in vivo. Lastly, we show that β cells secrete and bind DA in situ in response to glucose stimulation. Conclusions We provide proof-of-principle evidence for the existence of a novel postprandial circuit of glucose homeostasis dependent on nutritional tyrosine. DA and L-DOPA derived from nutritional tyrosine may serve to defend against hypoglycemia via inhibition of glucose-stimulated β-cell insulin secretion as proposed by the anti-incretin hypothesis. Nutritional tyrosine is metabolized to L DOPA and DA in the foregut. Postprandial L-DOPA and DA plasma concentrations rise in response to tyrosine. Oral stable isotope labeled tyrosine is found postprandially in the pancreas as DA. L-DOPA and DA are inhibitors of beta cell glucose-stimulated insulin secretion. Postprandial L-DOPA and DA excursions are muted in certain bariatric surgery patients.
Collapse
Affiliation(s)
- Judith Korner
- Department of Medicine and the Naomi Berrie Diabetes Center, Columbia University, College of Physicians and Surgeons, New York, NY, 10032, USA
| | - Gary W Cline
- Yale Diabetes Research Center, Yale School of Medicine, New Haven, CT, 06520, USA
| | - Mark Slifstein
- Department of Psychiatry, Stony Brook University, Stony Brook, New York, NY, 11794, USA
| | - Pasquale Barba
- Institute of Genetics and Biophysics, Adriano Buzzati-Traverso, CNR, Naples, IT 80131, Italy
| | - Gina R Rayat
- Alberta Diabetes Institute, Ray Rajotte Surgical-Medical Research Institute, Department of Surgery, University of Alberta, Edmonton, AB, T6G 2E1 CA, Canada
| | - Gerardo Febres
- Department of Medicine and the Naomi Berrie Diabetes Center, Columbia University, College of Physicians and Surgeons, New York, NY, 10032, USA
| | - Rudolph L Leibel
- Department of Medicine and the Naomi Berrie Diabetes Center, Columbia University, College of Physicians and Surgeons, New York, NY, 10032, USA
| | - Antonella Maffei
- Department of Medicine and the Naomi Berrie Diabetes Center, Columbia University, College of Physicians and Surgeons, New York, NY, 10032, USA
| | - Paul E Harris
- Department of Medicine and the Naomi Berrie Diabetes Center, Columbia University, College of Physicians and Surgeons, New York, NY, 10032, USA.
| |
Collapse
|
17
|
Březina K, Duboué-Dijon E, Palivec V, Jiráček J, Křížek T, Viola CM, Ganderton TR, Brzozowski AM, Jungwirth P. Can Arginine Inhibit Insulin Aggregation? A Combined Protein Crystallography, Capillary Electrophoresis, and Molecular Simulation Study. J Phys Chem B 2018; 122:10069-10076. [DOI: 10.1021/acs.jpcb.8b06557] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Kryštof Březina
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 542/2, 160 00 Prague, Czech Republic
| | - Elise Duboué-Dijon
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 542/2, 160 00 Prague, Czech Republic
| | - Vladimír Palivec
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 542/2, 160 00 Prague, Czech Republic
| | - Jiří Jiráček
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 542/2, 160 00 Prague, Czech Republic
| | - Tomáš Křížek
- Faculty of Science, Department of Analytical Chemistry, Charles University, Albertov 2030, 12840 Prague 2, Czech Republic
| | - Cristina M. Viola
- York Structural Biology Laboratory, Department of Chemistry, The University of York, Heslington, York YO10 5DD, United Kingdom
| | - Timothy R. Ganderton
- York Structural Biology Laboratory, Department of Chemistry, The University of York, Heslington, York YO10 5DD, United Kingdom
| | - Andrzej M. Brzozowski
- York Structural Biology Laboratory, Department of Chemistry, The University of York, Heslington, York YO10 5DD, United Kingdom
| | - Pavel Jungwirth
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 542/2, 160 00 Prague, Czech Republic
| |
Collapse
|