1
|
Marabelli C, Santiago DJ, Priori SG. The Structural-Functional Crosstalk of the Calsequestrin System: Insights and Pathological Implications. Biomolecules 2023; 13:1693. [PMID: 38136565 PMCID: PMC10741413 DOI: 10.3390/biom13121693] [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: 10/30/2023] [Revised: 11/14/2023] [Accepted: 11/21/2023] [Indexed: 12/24/2023] Open
Abstract
Calsequestrin (CASQ) is a key intra-sarcoplasmic reticulum Ca2+-handling protein that plays a pivotal role in the contraction of cardiac and skeletal muscles. Its Ca2+-dependent polymerization dynamics shape the translation of electric excitation signals to the Ca2+-induced contraction of the actin-myosin architecture. Mutations in CASQ are linked to life-threatening pathological conditions, including tubular aggregate myopathy, malignant hyperthermia, and Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT). The variability in the penetrance of these phenotypes and the lack of a clear understanding of the disease mechanisms associated with CASQ mutations pose a major challenge to the development of effective therapeutic strategies. In vitro studies have mainly focused on the polymerization and Ca2+-buffering properties of CASQ but have provided little insight into the complex interplay of structural and functional changes that underlie disease. In this review, the biochemical and structural natures of CASQ are explored in-depth, while emphasizing their direct and indirect consequences for muscle Ca2+ physiology. We propose a novel functional classification of CASQ pathological missense mutations based on the structural stability of the monomer, dimer, or linear polymer conformation. We also highlight emerging similarities between polymeric CASQ and polyelectrolyte systems, emphasizing the potential for the use of this paradigm to guide further research.
Collapse
Affiliation(s)
- Chiara Marabelli
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy;
- Laboratory of Molecular Cardiology, IRCCS ICS Maugeri, 27100 Pavia, Italy
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 28029 Madrid, Spain;
| | - Demetrio J. Santiago
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 28029 Madrid, Spain;
| | - Silvia G. Priori
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy;
- Laboratory of Molecular Cardiology, IRCCS ICS Maugeri, 27100 Pavia, Italy
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 28029 Madrid, Spain;
| |
Collapse
|
2
|
Ross AJ, Krumova I, Tunc B, Wu Q, Wu C, Camelliti P. A novel method to extend viability and functionality of living heart slices. Front Cardiovasc Med 2023; 10:1244630. [PMID: 37881724 PMCID: PMC10597746 DOI: 10.3389/fcvm.2023.1244630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 08/09/2023] [Indexed: 10/27/2023] Open
Abstract
Living heart slices have recently emerged as a powerful experimental model for fundamental cardiac research. By retaining the structure and function of the native myocardium while maintaining the simplicity of cell culture models, heart slices can be easily employed in electrophysiological, pharmacological, biochemical, and structural investigations. One single heart yields many slices (>20 slices for rodents, >100 slices for porcine or human hearts), however due to the low throughput of most assays and rapid slice degeneration within 24 h of preparation, many slices remain unused and are discarded at the end of the preparation day. Here we present a novel method to extend viability and functionality of living heart slices, enabling their use in experiments over several consecutive days following preparation. By combining hypothermic conditions with inhibition of myosin II ATPase using 2,3-butanedione monoxime (BDM), slices prepared from the left ventricle of porcine hearts remain viable and exhibit preserved contractile function and morphology for up to 6 days. Electrophysiological function was also confirmed over the 6 days by extracellular field potentials recordings. This simple method not only maximizes the use of slices prepared from one single heart, thus reducing the number of animals required, but also increases data reproducibility by allowing multiple electrophysiological, pharmacological, biochemical, and structural studies to be performed from the same heart.
Collapse
Affiliation(s)
- Abigail J. Ross
- School of Biosciences and Medicine, University of Surrey, Guildford, United Kingdom
| | - Iva Krumova
- School of Biosciences and Medicine, University of Surrey, Guildford, United Kingdom
| | - Berfin Tunc
- School of Biosciences and Medicine, University of Surrey, Guildford, United Kingdom
| | - Qin Wu
- School of Biosciences and Medicine, University of Surrey, Guildford, United Kingdom
- School of Medicine, Jiangsu Vocational College of Medicine, Yancheng, China
| | - Changhao Wu
- School of Biosciences and Medicine, University of Surrey, Guildford, United Kingdom
| | - Patrizia Camelliti
- School of Biosciences and Medicine, University of Surrey, Guildford, United Kingdom
| |
Collapse
|
3
|
Chen-Izu Y, Hegyi B, Jian Z, Horvath B, Shaw JA, Banyasz T, Izu LT. INNOVATIVE TECHNIQUES AND NEW INSIGHTS: Studying cardiac ionic currents and action potentials in physiologically relevant conditions. PHYSIOLOGICAL MINI-REVIEWS 2023; 16:22-34. [PMID: 38107545 PMCID: PMC10722976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Cardiac arrhythmias are associated with various forms of heart diseases. Ventricular arrhythmias present a significant risk for sudden cardiac death. Atrial fibrillations predispose to blood clots leading to stroke and heart attack. Scientists have been developing patch-clamp technology to study ion channels and action potentials (APs) underlying cardiac excitation and arrhythmias. Beyond the traditional patch-clamp techniques, innovative new techniques were developed for studying complex arrhythmia mechanisms. Here we review the recent development of methods including AP-Clamp, Dynamic Clamp, AP-Clamp Sequential Dissection, and Patch-Clamp-in-Gel. These methods provide powerful tools for researchers to decipher how the dynamic systems in excitation-Ca2+ signaling-contraction feedforward and feedback to control cardiac function and how their dysregulations lead to heart diseases.
Collapse
Affiliation(s)
- Ye Chen-Izu
- Department of Pharmacology, University of California, Davis, USA
- Department of Biomedical Engineering, University of California, Davis, USA
- Department of Internal Medicine, Division of Cardiovascular Medicine, University of California, Davis, USA
| | - Bence Hegyi
- Department of Pharmacology, University of California, Davis, USA
| | - Zhong Jian
- Department of Pharmacology, University of California, Davis, USA
| | - Balazs Horvath
- Department of Pharmacology, University of California, Davis, USA
- Department of Physiology, University of Debrecen, Hungary
| | - John A. Shaw
- Department of Pharmacology, University of California, Davis, USA
- Department of Aerospace Engineering, University of Michigan, Ann Arbor, USA
| | - Tamas Banyasz
- Department of Pharmacology, University of California, Davis, USA
- Department of Physiology, University of Debrecen, Hungary
| | - Leighton T. Izu
- Department of Pharmacology, University of California, Davis, USA
| |
Collapse
|
4
|
Lyu Y, Timofeyev V, Overton J, Thai PN, Yamoah EN, Chiamvimonvat N, Zhang XD. Protocol to record and quantify the intracellular pH in contracting cardiomyocytes. STAR Protoc 2022; 3:101301. [PMID: 35463464 PMCID: PMC9026584 DOI: 10.1016/j.xpro.2022.101301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Intracellular pH (pHi) plays critical roles in the regulation of cardiac function. Methods and techniques for cardiac pHi measurement have continued to evolve since early 1960s. Fluorescent microscopy is the most recently developed technique with several advantages over other techniques including higher spatial and temporal resolutions, and feasibility for contracting cell measurement. Here, we describe detailed methods for mouse cardiomyocyte isolation, and simultaneous measurement and quantification of pHi and sarcomere length in contracting cardiomyocytes. For complete details on the use and execution of this protocol, please refer to Lyu et al. (2022).
Collapse
Affiliation(s)
- Yankun Lyu
- Department of Internal Medicine, University of California, Davis, Davis, CA 95616, USA
| | - Valeriy Timofeyev
- Department of Internal Medicine, University of California, Davis, Davis, CA 95616, USA
| | - James Overton
- Department of Internal Medicine, University of California, Davis, Davis, CA 95616, USA
| | - Phung N. Thai
- Department of Internal Medicine, University of California, Davis, Davis, CA 95616, USA
| | - Ebenezer N. Yamoah
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV 89557, USA
| | - Nipavan Chiamvimonvat
- Department of Internal Medicine, University of California, Davis, Davis, CA 95616, USA
- Department of Veterans Affairs, Northern California Health Care System, Mather, CA 95655, USA
| | - Xiao-Dong Zhang
- Department of Internal Medicine, University of California, Davis, Davis, CA 95616, USA
- Department of Veterans Affairs, Northern California Health Care System, Mather, CA 95655, USA
| |
Collapse
|