Endoplasmic Reticulum Stress Mediates Vascular Smooth Muscle Cell Calcification via Increased Release of Grp78 (Glucose-Regulated Protein, 78 kDa)-Loaded Extracellular Vesicles
Copyright policy )Endoplasmic Reticulum Stress Mediates Vascular Smooth Muscle Cell Calcification via Increased Release of Grp78 (Glucose-Regulated Protein, 78 kDa)-Loaded Extracellular Vesicles
Objective: Vascular calcification is common among aging populations and mediated by vascular smooth muscle cells (VSMCs). The endoplasmic reticulum (ER) is involved in protein folding and ER stress has been implicated in bone mineralization. The role of ER stress in VSMC-mediated calcification is less clear. Approach and Results: mRNA expression of the ER stress markers PERK (PKR (protein kinase RNA)-like ER kinase), ATF (activating transcription factor) 4, ATF6, and Grp78 (glucose-regulated protein, 78 kDa) was detectable in human vessels with levels of PERK decreased in calcified plaques compared to healthy vessels. Protein deposition of Grp78/Grp94 was increased in the matrix of calcified arteries. Induction of ER stress accelerated human primary VSMC-mediated calcification, elevated expression of some osteogenic markers (Runx2 [RUNX family transcription factor 2], OSX [Osterix], ALP [alkaline phosphatse], BSP [bone sialoprotein], and OPG [osteoprotegerin]), and decreased expression of SMC markers. ER stress potentiated extracellular vesicle (EV) release via SMPD3 (sphingomyelin phosphodiesterase 3). EVs from ER stress-treated VSMCs showed increased Grp78 levels and calcification. Electron microscopy confirmed the presence of Grp78/Grp94 in EVs. siRNA (short interfering RNA) knock-down of Grp78 decreased calcification. Warfarin-induced Grp78 and ATF4 expression in rat aortas and VSMCs and increased calcification in an ER stress-dependent manner via increased EV release. Conclusions: ER stress induces vascular calcification by increasing release of Grp78-loaded EVs. Our results reveal a novel mechanism of action of warfarin, involving increased EV release via the PERK-ATF4 pathway, contributing to calcification. This study is the first to show that warfarin induces ER stress and to link ER stress to cargo loading of EVs.
- Maastricht University Netherlands
- King's College London United Kingdom
TRANSCRIPTION FACTOR 4, Male, ARTERIAL CALCIFICATION, Extracellular Vesicles/drug effects, Muscle, Smooth, Vascular, ACTIVATION, arteries, Rats, Sprague-Dawley, Translational Sciences, Heat-Shock Proteins/genetics, Endoplasmic Reticulum Chaperone BiP, Vascular/drug effects, Smooth Muscle/metabolism, Cells, Cultured, Heat-Shock Proteins, Cultured, Middle Aged, Endoplasmic Reticulum Stress, Warfarin/toxicity, APOPTOSIS, Vascular Calcification/chemically induced, eIF-2 Kinase/genetics, endoplasmic reticulum, vascular calcification, Muscle, Female, Smooth, Signal Transduction, Activating Transcription Factor 4/genetics, Adult, Adolescent, Cells, Myocytes, Smooth Muscle, INHIBITION, MATRIX GLA-PROTEIN, CALCIUM, OSTEOBLAST DIFFERENTIATION, MECHANISMS, Young Adult, Extracellular Vesicles, Endoplasmic Reticulum Stress/drug effects, KINASE, Animals, Humans, Aged, Myocytes, Animal, aging, Activating Transcription Factor 4, Rats, warfarin, Disease Models, Animal, Gene Expression Regulation, Disease Models, Sprague-Dawley
TRANSCRIPTION FACTOR 4, Male, ARTERIAL CALCIFICATION, Extracellular Vesicles/drug effects, Muscle, Smooth, Vascular, ACTIVATION, arteries, Rats, Sprague-Dawley, Translational Sciences, Heat-Shock Proteins/genetics, Endoplasmic Reticulum Chaperone BiP, Vascular/drug effects, Smooth Muscle/metabolism, Cells, Cultured, Heat-Shock Proteins, Cultured, Middle Aged, Endoplasmic Reticulum Stress, Warfarin/toxicity, APOPTOSIS, Vascular Calcification/chemically induced, eIF-2 Kinase/genetics, endoplasmic reticulum, vascular calcification, Muscle, Female, Smooth, Signal Transduction, Activating Transcription Factor 4/genetics, Adult, Adolescent, Cells, Myocytes, Smooth Muscle, INHIBITION, MATRIX GLA-PROTEIN, CALCIUM, OSTEOBLAST DIFFERENTIATION, MECHANISMS, Young Adult, Extracellular Vesicles, Endoplasmic Reticulum Stress/drug effects, KINASE, Animals, Humans, Aged, Myocytes, Animal, aging, Activating Transcription Factor 4, Rats, warfarin, Disease Models, Animal, Gene Expression Regulation, Disease Models, Sprague-Dawley
selected citations These citations are derived from selected sources.This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).64 popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.Top 1% influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).Top 10% impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.Top 1%
Citations provided by BIP!Popularity provided by BIP!