Impaired proteostasis in senescent vascular endothelial cells: a perspective on estrogen and oxidative stress in the aging vasculature.
Am J Physiol Heart Circ Physiol
; 316(2): H421-H429, 2019 02 01.
Article
in En
| MEDLINE
| ID: mdl-30499713
ABSTRACT
The heat shock response is an important cytoprotective mechanism for protein homeostasis and is an essential protective response to cellular stress and injury. Studies on changes in the heat shock response with aging have been mixed with regard to whether it is inhibited, and this, at least in part, reflects different tissues and different models. Cellular senescence is a key feature in aging, but work on the heat shock response in cultured senescent (SEN) cells has largely been limited to fibroblasts. Given the prevalence of oxidative injury in the aging cardiovascular system, we investigated whether SEN primary human coronary artery endothelial cells have a diminished heat shock response and impaired proteostasis. In addition, we tested whether this downregulation of heat shock response can be mitigated by 17ß-estradiol (E2), which has a critical cardioprotective role in women, as we have previously reported that E2 improves the heat shock response in endothelial cells (Hamilton KL, Mbai FN, Gupta S, Knowlton AA. Arterioscler Thromb Vasc Biol 24 1628-1633, 2004). We found that SEN endothelial cells, despite their unexpectedly increased proteasome activity, had a diminished heat shock response and had more protein aggregation than early passage cells. SEN cells had increased oxidative stress, which promoted protein aggregation. E2 treatment did not decrease protein aggregation or improve the heat shock response in either early passage or SEN cells. In summary, cellular senescence in adult human endothelial cells is accompanied by increased oxidative stress and a blunting of proteostasis, and E2 did not mitigate these changes. NEW & NOTEWORTHY Senescent human endothelial cells have a diminished heat shock response and increased protein aggregates. Senescent human endothelial cells have increased basal oxidative stress, which increases protein aggregates. Physiological level of 17ß-estradiol did not improve proteostasis in endothelial cells.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Endothelium, Vascular
/
Cellular Senescence
/
Oxidative Stress
/
Endothelial Cells
/
Estradiol
/
Estrogens
/
Proteostasis
Type of study:
Risk_factors_studies
Limits:
Adolescent
/
Adult
/
Female
/
Humans
/
Middle aged
Language:
En
Journal:
Am J Physiol Heart Circ Physiol
Journal subject:
CARDIOLOGIA
/
FISIOLOGIA
Year:
2019
Document type:
Article