During embryonic development, cells comprising the outermost layer of the heart or epicardium play a critical role in the formation of the coronary vasculature. Thus, uncovering the molecular mechanisms that govern epicardial cell behavior is imperative to better understand the etiology of cardiovascular diseases. In this study, we investigated the function of hyaluronan (HA), a major component of the extracellular matrix, in the modulation of epicardial signaling. We show that stimulation of epicardial cells with high molecular weight HA (HMW-HA) promotes the association of MEKK1 with the HA receptor CD44 and induces MEKK1 phosphorylation. This leads to the activation of two distinct pathways, one ERK-dependent and another NFkappaB-dependent. Furthermore, HMW-HA stimulates epicardial cells to differentiate and invade, as suggested by increased vimentin expression and enhanced invasion through a collagen matrix. Blockade of CD44, transfection with a kinase-inactive MEKK1 construct or the use of ERK1/2 and NFkappaB inhibitors significantly abrogates the invasive response to HMW-HA. Together, these findings suggest an important role for HA in the regulation of epicardial cell fate via activation of MEKK1 signaling cascades.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2846756PMC
http://dx.doi.org/10.1016/j.cellsig.2010.02.004DOI Listing

Publication Analysis

Top Keywords

epicardial cell
12
mekk1 signaling
8
regulation epicardial
8
cell behavior
8
epicardial cells
8
epicardial
6
involvement mekk1
4
signaling pathway
4
pathway regulation
4
behavior hyaluronan
4

Similar Publications

The Wilms' tumor suppressor WT1 is essential for the development of the heart, among other organs such as the kidneys and gonads. The Wt1 gene encodes a zinc finger transcription factor that regulates proliferation, cellular differentiation processes, and apoptosis. WT1 is also involved in cardiac homeostasis and repair.

View Article and Find Full Text PDF

FoxP3 T-regulatory (Treg) lymphocytes and cytokine production by cells from the stromal vascular fraction (SVF) of epicardial (EAT) and thymus (TAT) adipose tissue of 42 patients with chronic coronary heart disease (CHD) were studied. In the SVF of TAT in patients with Gensini Score (GS)≥74 (the most severe atherosclerosis), the production of IL-1β, TNF, IL-4, and IFNγ was higher, while FoxP3 translocation into the nucleus was lower than in patients with GS<74. The GS index directly correlated with the production of IL-4, IL-1β, and TNF by cells of the SVF of TAT, and inversely - with the production of TNF, IL-17, and IL-10 by cells of the SVF of EAT.

View Article and Find Full Text PDF

Cytokeratin-positive interstitial reticulum cell (CIRC) tumor is an extremely rare malignant neoplasm and a subtype of fibroblastic reticular cell tumor, classified within the dendritic cell tumor group. We describe a case of an epicardial CIRC tumor that was resected and subsequently recurred in the left pulmonary hilum. This recurrence was treated with immunotherapy followed by radiotherapy.

View Article and Find Full Text PDF

Cardiac fibroblasts are activated following myocardial infarction (MI) and cardiac fibrosis is a major driver of the growing burden of heart failure. A non-invasive targeting method for activated cardiac fibroblasts would be advantageous because of their importance for imaging and therapy. Targeting was achieved by linking a 7-amino acid peptide (EP9) to a perfluorocarbon-containing nanoemulsion (PFC-NE) for visualization by F-combined with H-MRI.

View Article and Find Full Text PDF

Generation and characterization of three induced pluripotent stem cell lines for modeling coronary artery vasospasm.

Stem Cell Res

February 2025

Cardiology Section, Medical Service, Veterans Affairs Palo Alto Health Care System, Palo Alto, CA, USA; Radiology Service, Veterans Affairs Palo Alto Health Care System, Palo Alto, CA, USA; Division of Cardiovascular Medicine, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA; Department of Radiology, Stanford University School of Medicine, Stanford, CA, USA; Stanford Cardiovascular Institute, Stanford University, Stanford, CA, USA.

Coronary artery vasospasm (CAV) is characterized by transient constriction of epicardial coronary arteries leading to angina. Its disease mechanisms are multifactorial but has centered mostly on endothelial dysfunction and smooth muscle hyperreactivity. To facilitate the investigation of these mechanisms in cell culture, we generated and characterized three induced pluripotent stem cell (iPSC) lines from patients with CAV.

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!