Cell sex determines anoikis resistance in vascular smooth muscle cells

Abstract 

Sexual dimorphism, detectable in vascular smooth muscle cells freshly isolated from aorta of male and female rats, is associated with a different susceptibility to radiation-induced apoptosis. In this work we investigated the mechanism underlying this difference and discovered that, in comparison with cells from male rats, cells from female rats show adhesion-associated resistance to apoptosis, the so called anoikis resistance. This is apparently due to a more adhering phenotype, characterized by a well organized actin microfilament cytoskeleton and to an increased phosphorylated focal adhesion kinase, and, more importantly, to a higher propensity to undergo survival by autophagy.

Abbreviations: ROS, reactive oxygen species, VSMC, vascular smooth muscle cells, MVSMC, male-derived vascular smooth muscle cells, FVSMC, female-derived vascular smooth muscle cells, 4-HNE, 4-hydroxynonenal, FAK, focal adhesion kinase, p-FAK, phosphorylated focal adhesion kinase, SEM, scanning electron microscopy, UVB, ultraviolet B radiation, E2, estradiol, ERs, estrogen receptors, AR, androgen receptors

Keywords: Reactive oxygen species, Vascular smooth muscle cells, Apoptosis, Gender, Anoikis, Cell adhesion, Autophagy, Senescence