AI Article Synopsis

  • The study investigates how cardiac core circadian genes affect the occurrence of ventricular arrhythmias (VAs) in chronic heart failure (CHF), revealing a distinct pattern in their incidence over the day.
  • The researchers created a guinea pig model of CHF and found that while the core clock genes remained stable, VAs were more frequent at certain times, peaking at CT3 compared to CT15 after stimulation.
  • They concluded that CLOCK-BMAL1 regulates β1-adrenergic receptor (β1-AR) expression, which in turn influences the rhythm of VAs in CHF, highlighting a transcriptional link between circadian biology and heart arrhythmias.

Article Abstract

The incidence of ventricular arrhythmias (VAs) in chronic heart failure (CHF) exhibits a notable circadian rhythm, for which the underlying mechanism has not yet been well defined. Thus, we aimed to investigate the role of cardiac core circadian genes on circadian VAs in CHF. First, a guinea pig CHF model was created by transaortic constriction. Circadian oscillation of core clock genes was evaluated by RT-PCR and was found to be unaltered in CHF (P > 0.05). Using programmed electrical stimulation in Langendorff-perfused failing hearts, we discovered that the CHF group exhibited increased VAs with greater incidence at CT3 compared to CT15 upon isoproterenol (ISO) stimulation. Circadian VAs was blunted by a β1-AR-selective blocker rather than a β2-AR-selective blocker. Circadian oscillation of β1-AR was retained in CHF (P > 0.05) and a 4-h phase delay between β1-AR and CLOCK-BMAL1 was recorded. Therefore, when CLOCK-BMAL1 was overexpressed using adenovirus infection, an induced overexpression of β1-AR also ensued, which resulted in prolonged action potential duration (APD) and enhanced arrhythmic response to ISO stimulation in cardiomyocytes (P < 0.05). Finally, chromatin immunoprecipitation and luciferase assays confirmed that CLOCK-BMAL1 binds to the enhancer of β1-AR gene and upregulates β1-AR expression. Therefore, in this study, we discovered that CLOCK-BMAL1 regulates the expression of β1-AR on a transcriptional level and subsequently modulates circadian VAs in CHF.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7653582PMC

Publication Analysis

Top Keywords

circadian oscillation
12
circadian vas
12
clock-bmal1 regulates
8
circadian
8
ventricular arrhythmias
8
failing hearts
8
vas chf
8
chf 005
8
iso stimulation
8
chf
7

Similar Publications

Many animals display physiological and behavioral activities limited to specific times of the day. Certain insects exhibit clear daily rhythms in their mating activities that are regulated by an internal biological clock. However, the specific genetic mechanisms underlying this regulation remain largely unexplored.

View Article and Find Full Text PDF

Maternal circadian rhythms during pregnancy dictate metabolic plasticity in offspring.

Cell Metab

January 2025

Division of Endocrinology, Metabolism, and Nephrology, Department of Internal Medicine, Keio University School of Medicine, Tokyo, Japan; Center for Preventive Medicine, Keio University, Tokyo, Japan. Electronic address:

Tissue-level oscillation is achieved by tissue-intrinsic clocks along with network-dependent signals originating from distal organs and organismal behavior. Yet, it remains unexplored whether maternal circadian rhythms during pregnancy influence fetal rhythms and impact long-term susceptibility to dietary challenges in offspring. Here, we demonstrate that circadian disruption during pregnancy decreased placental and neonatal weight yet retained transcriptional and structural maturation.

View Article and Find Full Text PDF

One of the most important goals of contemporary biology is to understand the principles of the molecular order underlying the complex dynamic architecture of cells. Here, we present an overview of the main driving forces involved in the cellular molecular complexity and in the emergent functional dynamic structures, spanning from the most basic molecular organization levels to the complex emergent integrative systemic behaviors. First, we address the molecular information processing which is essential in many complex fundamental mechanisms such as the epigenetic memory, alternative splicing, regulation of transcriptional system, and the adequate self-regulatory adaptation to the extracellular environment.

View Article and Find Full Text PDF

Study Objectives: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) may improve sleep dysfunction, a common non-motor symptom of Parkinson disease (PD). Improvement in motor symptoms correlates with DBS-suppressed local field potential (LFP) activity, particularly in the beta frequency (13 - 30 Hz). Although well-characterized in the short term, little is known about the innate progression of these oscillations across the sleep-wake cycle.

View Article and Find Full Text PDF

Background/objectives: Circadian clocks are endogenous systems that regulate numerous biological, physiological, and behavioral events in living organisms. Aging attenuates the precision and robustness of circadian clocks, leading to prolonged and dampened circadian gene oscillation rhythms and amplitudes. This study investigated the effects of food-derived polyphenols such as ellagic acid and its metabolites (urolithin A, B, and C) on the aging clock at the cellular level using senescent human fibroblast cells, TIG-3 cells.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!