The objective of this article is to present an in vitro model of atrial cardiac tissue that could serve to study the mechanisms of remodeling related to atrial fibrillation (AF). We analyze the modification on gene expression and modifications on rotor dynamics following tissue remodeling. Atrial murine cells (HL-1 myocytes) were maintained in culture after the spontaneous initiation of AF and analyzed at two time points: 3.1 ± 1.3 and 9.7 ± 0.5 days after AF initiation. The degree of electrophysiological remodeling (i.e., relative gene expression of key ion channels) and structural inhomogeneity was compared between early and late cell culture times both in nonfibrillating and fibrillating cell cultures. In addition, the electrophysiological characteristics of in vitro fibrillation [e.g., density of phase singularities (PS/cm(2)), dominant frequency, and rotor meandering] analyzed by means of optical mapping were compared with the degree of electrophysiological remodeling. Fibrillating cell cultures showed a differential ion channel gene expression associated with atrial tissue remodeling (i.e., decreased SCN5A, CACN1C, KCND3, and GJA1 and increased KCNJ2) not present in nonfibrillating cell cultures. Also, fibrillatory complexity was increased in late- vs. early stage cultures (1.12 ± 0.14 vs. 0.43 ± 0.19 PS/cm(2), P < 0.01), which was associated with changes in the electrical reentrant patterns (i.e., decrease in rotor tip meandering and increase in wavefront curvature). HL-1 cells can reproduce AF features such as electrophysiological remodeling and an increased complexity of the electrophysiological behavior associated with the fibrillation time that resembles those occurring in patients with chronic AF.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1152/ajpheart.00055.2015 | DOI Listing |
J Am Chem Soc
January 2025
School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore.
Photodynamic therapy (PDT) holds promise as a cancer treatment modality due to its potential for enhanced therapy precision and safety. To enhance deep tissue penetration and minimize tissue adsorption and phototoxicity, developing photosensitizers activated by second near-infrared window (NIR-II) light shows significant potential. However, the efficacy of PDT is often impeded by tumor microenvironment hypoxia, primarily caused by irregular tumor vasculature.
View Article and Find Full Text PDFPLoS One
January 2025
Department of Pharmacy Practice, Faculty of Pharmacy, Airlangga University, Surabaya, Indonesia.
Hydroxyapatite (HA) is widely used as a bone graft. However, information on the head-to-head osteoinductivity and in vivo performance of micro- and nanosized natural and synthetic HA is still lacking. Here, we fabricated nanosized bovine HA (nanoBHA) by using a wet ball milling method and compared its in vitro and in vivo performance with microsized BHA, nanosized synthetic HA (nanoHA), and microsized synthetic HA (HA).
View Article and Find Full Text PDFActa Physiol (Oxf)
February 2025
Zoophysiology, Department of Biology, Aarhus University, Aarhus C, Denmark.
Aim: Snakes exhibit remarkable physiological shifts when their large meals induce robust postprandial growth after prolonged fasting. To understand the regulatory mechanisms underlying this rapid metabolic transition, we examined the regulation of protein synthesis in pythons, focusing on processes driving early postprandial tissue remodeling and growth.
Methods: Using the SUnSET method with puromycin labeling, we measured in vivo protein synthesis in fasting and digesting snakes at multiple post-feeding intervals.
J Biomed Mater Res B Appl Biomater
February 2025
Bioassays and Cellular Dynamics Lab, Department of Chemical and Biological Sciences, Institute of Biosciences, UNESP: São Paulo State University, São Paulo, Brazil.
Calcium phosphates, notably monetite, are valued biomaterials for bone applications owing to their osteogenic properties and rapid uptake by bone cells. This study investigates the enhancement of these properties through Cobalt doping, which is known to induce hypoxia and promote bone cell differentiation. Heat treatments at 700°C, 900°C, and 1050°C are applied to both monetite and Cobalt-doped monetite, facilitating the development of purer, more crystalline phases with varied particle sizes and optimized cellular responses.
View Article and Find Full Text PDFBiogerontology
January 2025
UCIBIO-Applied Molecular Biosciences Unit, Translational Toxicology Research Laboratory, University Institute of Health Sciences (1H-TOXRUN, IUCS-CESPU), 4585-116, Gandra, Portugal.
Sarcopenia and cancer cachexia are two life-threatening conditions often misdiagnosed. The skeletal muscle is one of the organs most adversely affected by these conditions, culminating in poor quality of life and premature mortality. In addition, it has been suggested that chemotherapeutic agents exacerbate cancer cachexia, as is the case of doxorubicin.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!