Article
Multidisciplinary Sciences
Cristina M. Risi, Ian Pepper, Betty Belknap, Maicon Landim-Vieira, Howard D. White, Kelly Dryden, Jose R. Pinto, P. Bryant Chase, Vitold E. Galkin
Summary: The study reveals the structural composition of cardiac thin filaments under systolic Ca2+ levels, showing that the two strands of the thin filament consist of troponin complexes with different binding states and short-range cooperativity. These findings suggest a mechanism by which cardiac muscle is regulated by narrow range Ca2+ fluctuations.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Biochemistry & Molecular Biology
Natalia A. Koubassova, Andrey K. Tsaturyan
Summary: Contraction of cardiac muscle is regulated by Ca2+ ions via regulatory proteins, troponin (Tn), and tropomyosin (Tpm) associated with the thin (actin) filaments in myocardial sarcomeres. Recent cryo-electron microscopy (cryo-EM) models of the complex allow one to study the dynamic and mechanical properties of the complex using molecular dynamics (MD). However, further refinement of the models is needed to improve the protein-protein interaction in some regions of the complex, as suggested by problems revealed from the MD simulation.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Automation & Control Systems
Lianghao Ji, Yanxue Shi, Cuijuan Zhang
Summary: This paper investigates the multi-group consensus problem for heterogeneous networks using pinning control and adaptive coupling weight methods. The results indicate that the in-degree of the agents and pinning gains are closely related to achieving consensus, and the adaptive coupling weight method can increase the convergence rate of the network. Simulation experiments verify the theoretical results.
INTERNATIONAL JOURNAL OF SYSTEMS SCIENCE
(2022)
Article
Neurosciences
Ena Ivanovic, Jan P. Kucera
Summary: It has been suggested that the localization of Na+ channel clusters in the perinexi of gap junction plaques is crucial for ephaptic coupling in cardiac tissue, which is greatly modulated by perinexal width.
JOURNAL OF PHYSIOLOGY-LONDON
(2021)
Article
Cell Biology
Marston Bradshaw, John M. Squire, Edward Morris, Georgia Atkinson, Rebecca Richardson, Jon Lees, Massimo Caputo, Giulia M. Bigotti, Danielle M. Paul
Summary: This study used cryo-EM to investigate the three-dimensional structure of zebrafish cardiac thin and actin filaments, and found that they have the same fundamental organization as human reconstituted thin filaments. Zebrafish, as a model organism for human disease research, have similar genes and disease-causing genes to humans, making them suitable for studying human diseases.
JOURNAL OF MUSCLE RESEARCH AND CELL MOTILITY
(2023)
Article
Biophysics
Sarah Kosta, Dylan Colli, Qiang Ye, Kenneth S. Campbell
Summary: FiberSim is a flexible open-source model that simulates myofilament-level contraction, allowing for the exploration of mechanisms modulated by myosin-binding protein C and varying isoform expression levels. This user-friendly software is designed for efficient simulations on regular laptops and may accelerate research focused on sarcomere contractile properties.
BIOPHYSICAL JOURNAL
(2022)
Review
Physiology
Alex Lewalle, Kenneth S. Campbell, Stuart G. Campbell, Gregory N. Milburn, Steven A. Niederer
Summary: Myofilaments and associated proteins form sarcomeres, which are responsible for muscle contraction. Skinned muscle preparations have been instrumental in understanding the contractile mechanisms of skeletal and cardiac muscle. However, there are inherent differences between skinned and intact muscle that pose challenges for experimentalists.
JOURNAL OF GENERAL PHYSIOLOGY
(2022)
Article
Cardiac & Cardiovascular Systems
Maria Papadaki, Theerachat Kampaengsri, Samantha K. Barrick, Stuart G. Campbell, Dirk von Lewinski, Peter P. Rainer, Samantha P. Harris, Michael J. Greenberg, Jonathan A. Kirk
Summary: The study found that increased glycation of sarcomeric actin in diabetic patients may contribute to the development of HF. This suggests that myofilament glycation could be a promising therapeutic target for preventing HF in diabetics.
JOURNAL OF MOLECULAR AND CELLULAR CARDIOLOGY
(2022)
Article
Cell Biology
Rajeshwary Ghosh, Jennifer Jason Gillaspie, Kenneth S. Campbell, J. David Symons, Sihem Boudina, James Scott Pattison
Summary: This study establishes a protective role for chaperone-mediated autophagy (CMA) in hypoxia-induced cardiomyocyte loss and suggests that CMA activation may offer a novel treatment for ischemic heart disease.
AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY
(2022)
News Item
Biophysics
Kenneth S. Campbell
BIOPHYSICAL JOURNAL
(2022)
Article
Cardiac & Cardiovascular Systems
Gregory N. Milburn, Faruk Moonschi, Ashley M. White, Mindy Thompson, Katherine Thompson, Emma J. Birks, Kenneth S. Campbell
Summary: This study aims to examine the effects of freezing on the contractile function of chemically permeabilized myocardium. The results showed that freezing had minimal impact on maximum isometric force, passive force, and Hill coefficients, but it did affect the pCa(50), causing a slight decrease.
JOURNAL OF THE AMERICAN HEART ASSOCIATION
(2022)
Article
Cardiac & Cardiovascular Systems
D. V. Rasicci, J. Ge, G. N. Milburn, N. B. Wood, A. M. Pruznak, C. H. Lang, M. J. Previs, K. S. Campbell, C. M. Yengo
Summary: This study investigates the molecular changes in cardiac muscle contraction during ischemic heart failure (IHF). The results show that the biophysical properties of cardiac myosin are altered in IHF, which is associated with reduced contractile function and pathological remodeling of the heart. These findings suggest that targeting the myosin motor may be an effective pharmacological intervention for ischemia.
AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY
(2023)
Article
Physiology
Bertrand C. W. Tanner, Peter O. Awinda, Keinan B. Agonias, Seetharamaiah Attili, Cheavar A. Blair, Mindy S. Thompson, Lori A. Walker, Thomas Kampourakis, Kenneth S. Campbell
Summary: Isometric force-pCa relationships were measured in human myocardial strips at physiological temperature. Ca2+ sensitivity increased with sarcomere length in samples from donors and patients with ischemic heart failure, but not in samples from patients with non-ischemic heart failure. Troponin I and cMyBP-C phosphorylation promote length-dependent activation, which is blunted in myocardium from patients with ischemic heart failure and further reduced in myocardium from patients with non-ischemic heart failure.
JOURNAL OF GENERAL PHYSIOLOGY
(2023)
Article
Physiology
Laurin M. Hanft, Joel C. Robinett, Theodore J. Kalogeris, Kenneth S. Campbell, Brandon J. Biesiadecki, Kerry S. McDonald
Summary: Phosphorylation of cardiac troponin I regulates myofilament power output and can increase power output in failing human hearts. PKA-mediated phosphorylation of myofibrillar proteins increases power in rodent cardiac myocytes. The study also found that specific phospho-residues of cardiac troponin I can increase power in skeletal muscle fibers and cardiac myocytes. These findings suggest that phosphorylation of cardiac troponin I is a molecular regulator of myocyte power and could be targeted for therapy in failing hearts.
JOURNAL OF GENERAL PHYSIOLOGY
(2023)
Article
Engineering, Biomedical
Lei Fan, Jenny S. Choy, Sangjin Lee, Kenneth S. Campbell, Jonathan F. Wenk, Ghassan S. Kassab, Daniel Burkhoff, Lik Chuan Lee
Summary: This study investigated the impact of the HeartMate 3 LVAD on right ventricular (RV) function using computer modeling. The results showed that the LVAD reduced RV chamber contractility at a higher pump speed, especially with a thinner septal wall or lower myocardial contractility.
Article
Cell & Tissue Engineering
Shi Shen, Stephanie Shao, Maria Papadaki, Jonathan A. A. Kirk, Stuart G. G. Campbell
Summary: This study evaluated decellularized porcine psoas muscle as an alternative scaffold for engineered heart tissue (EHT) formation. The results showed that decellularized psoas muscle scaffolds yielded EHTs that were similar to those made from decellularized myocardial tissue in terms of biomechanical characteristics and contractile behavior. However, psoas muscle scaffolds showed less variability and were less dependent on the region of origin compared to ventricular scaffolds.
TISSUE ENGINEERING PART C-METHODS
(2023)
Article
Cardiac & Cardiovascular Systems
Joohee Choi, Joshua B. Holmes, Kenneth S. Campbell, Julian E. Stelzer
Summary: OM and danicamtiv increase myocardial force output through different mechanisms, with OM significantly increasing Ca2+ sensitivity of force generation and danicamtiv having a less pronounced effect. Both drugs slow down cross-bridge kinetics, but danicamtiv has a more pronounced inhibitory effect on the OM-induced dynamic delay.
JOURNAL OF THE AMERICAN HEART ASSOCIATION
(2023)
Article
Multidisciplinary Sciences
Saiti S. Halder, Michael J. Rynkiewicz, Jenette G. Creso, Lorenzo R. Sewanan, Lindsey Howland, Jeffrey R. Moore, William Lehman, Stuart G. Campbell
Summary: Computational and experimental analysis showed that the TPM1 S215L mutation disrupts the mechanical and regulatory properties of tropomyosin, leading to hypercontractility and the development of hypertrophic cardiomyopathy.
Article
Cardiac & Cardiovascular Systems
Petr G. Vikhorev, Natalia N. Vikhoreva, WaiChun Yeung, Amy Li, Sean Lal, Cristobal G. dos Remedios, Cheavar A. Blair, Maya Guglin, Kenneth S. Campbell, Magdi H. Yacoub, Pieter de Tombe, Steven B. Marston
Summary: This study investigates the effects of truncating mutations in the titin gene (TTN) on the function and characteristics of myofibrils. The researchers found that these mutations lead to decreased length-dependent activation and increased elasticity of myofibrils. They also observed decreased phosphorylation levels of TnI and MyBP-C in DCM patients with TTN-truncating variants.
CARDIOVASCULAR RESEARCH
(2022)