Docosahexaenoic acid-induced unfolded protein response, cell cycle arrest, and apoptosis in vascular smooth muscle cells are triggered by Ca²⁺-dependent induction of oxidative stress

Copyright © 2012 Elsevier Inc. All rights reserved..

Proliferation of vascular smooth muscle cells is a characteristic of pathological vascular remodeling and represents a significant therapeutic challenge in several cardiovascular diseases. Docosahexaenoic acid (DHA), a member of the n-3 polyunsaturated fatty acids, was shown to inhibit proliferation of numerous cell types, implicating several different mechanisms. In this study we examined the molecular events underlying the inhibitory effects of DHA on proliferation of primary human smooth muscle cells isolated from small pulmonary artery (hPASMCs). DHA concentration-dependently inhibited hPASMC proliferation, induced G1 cell cycle arrest, and decreased cyclin D1 protein expression. DHA activated the unfolded protein response (UPR), evidenced by increased mRNA expression of HSPA5, increased phosphorylation of eukaryotic initiation factor 2α, and splicing of X-box binding protein 1. DHA altered cellular lipid composition and led to increased reactive oxygen species (ROS) production. DHA-induced ROS were dependent on both intracellular Ca(2+) release and entry of extracellular Ca(2+). Overall cellular ROS and mitochondrial ROS were decreased by RU360, a specific inhibitor of mitochondrial Ca(2+) uptake. DHA-induced mitochondrial dysfunction was evidenced by decreased mitochondrial membrane potential and decreased cellular ATP content. DHA triggered apoptosis as found by increased numbers of cleaved caspase-3- and TUNEL-positive cells. The free radical scavenger Tempol counteracted DHA-induced ROS, cell cycle arrest, induction of UPR, and apoptosis. We conclude that Ca(2+)-dependent oxidative stress is the central and initial event responsible for induction of UPR, cell cycle arrest, and apoptosis in DHA-treated hPASMCs.

Medienart:

E-Artikel

Erscheinungsjahr:

2012

Erschienen:

2012

Enthalten in:

Zur Gesamtaufnahme - volume:52

Enthalten in:

Free radical biology & medicine - 52(2012), 9 vom: 01. Mai, Seite 1786-95

Sprache:

Englisch

Beteiligte Personen:

Crnkovic, Slaven [VerfasserIn]
Riederer, Monika [VerfasserIn]
Lechleitner, Margarete [VerfasserIn]
Hallström, Seth [VerfasserIn]
Malli, Roland [VerfasserIn]
Graier, Wolfgang F [VerfasserIn]
Lindenmann, Jörg [VerfasserIn]
Popper, Helmut [VerfasserIn]
Olschewski, Horst [VerfasserIn]
Olschewski, Andrea [VerfasserIn]
Frank, Saša [VerfasserIn]

Links:

Volltext

Themen:

25167-62-8
Calcium
DNA Primers
Docosahexaenoic Acids
Endoplasmic Reticulum Chaperone BiP
HSPA5 protein, human
Journal Article
Research Support, Non-U.S. Gov't
SY7Q814VUP

Anmerkungen:

Date Completed 28.09.2012

Date Revised 03.12.2021

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.freeradbiomed.2012.02.036

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM21594996X