Estrogen Receptor Subtypes Elicit a Distinct Gene Expression Profile of Endothelial-Derived Factors Implicated in Atherosclerotic Plaque Vulnerability

Abstract

In the presence of established atherosclerosis, estrogens are potentially harmful. MMP-2 and MMP-9, their inhibitors (TIMP-2 and TIMP-1), RANK, RANKL, OPG, MCP-1, lysyl oxidase (LOX), PDGF-β, and ADAMTS-4 play critical roles in plaque instability/rupture. We aimed to investigate (i) the effect of estradiol on the expression of the abovementioned molecules in endothelial cells, (ii) which type(s) of estrogen receptors mediate these effects, and (iii) the role of p21 in the estrogen-mediated regulation of the aforementioned factors. Human aortic endothelial cells (HAECs) were cultured with estradiol in the presence or absence of TNF-α. The expression of the aforementioned molecules was assessed by qRT-PCR and ELISA. Zymography was also performed. The experiments were repeated in either ERα- or ERβ-transfected HAECs and after silencing p21. HAECs expressed only the GPR-30 estrogen receptor. Estradiol, at low concentrations, decreased MMP-2 activity by 15-fold, increased LOX expression by 2-fold via GPR-30, and reduced MCP-1 expression by 3.5-fold via ERβ. The overexpression of ERα increased MCP-1 mRNA expression by 2.5-fold. In a low-grade inflammation state, lower concentrations of estradiol induced the mRNA expression of MCP-1 (3.4-fold) and MMP-9 (7.5-fold) and increased the activity of MMP-2 (1.7-fold) via GPR-30. Moreover, p21 silencing resulted in equivocal effects on the expression of the abovementioned molecules. Estradiol induced different effects regarding atherogenic plaque instability through different ERs. The balance of the expression of the various ER subtypes may play an important role in the paradoxical characterization of estrogens as both beneficial and harmful.

Plasma TIMP-1 as a sex-specific biomarker for acute lung injury

“…In goat oviductal epithelial cells, estradiol can induce TIMP-1 expression [23]. A similar observation was reported in human aortic endothelial cells under inflammatory conditions but not normal conditions [24]. Thus, there is a possibility that TIMP-1 may be a gene that escapes X-chromosome inactivation during inflammatory events leading to severe ARDS.…”

“…Different from many X-linked genes, Anderson and colleagues reported that human TIMP-1 is prone to reactivation or variable in its inactivation [22]. In addition, it has been reported that estradiol can significantly induce TIMP-1 expression in goat oviductal epithelial cells [23] and human aortic endothelial cells under inflammatory conditions [24]. Thus, there is a possibility that TIMP-1 may serve as a sex-specific biomarker.…”

Integrated Analysis of Transcriptome and Proteome of the Human Cornea and Aqueous Humor Reveal Novel Biomarkers for Corneal Endothelial Cell Dysfunction

“…An additional 12 AH samples from each group were subjected to ELISA. AH proteins were measured using the human metallopeptidase inhibitor 1 (TIMP1) (DTM100; R&D Systems), angiopoietin-related protein 7 (ANGPTL7), and Fc fragment of IgG binding protein (FCGBP) ELISA Kit (CSB-EL001715HU, CSB-EL008536HU; Cusabio Technology) according to the manufacturer's instructions [48,49]. Briefly, all samples were brought to room temperature before use and were assayed in duplicate.…”

Sex-specific Impact of 17β-estradiol and Testosterone Levels on Inflammation and Injury in Acute Myocardial Infarction

“…In the absence of inflammatory stimuli, estrogens protect the initial stages of atherosclerosis in both sexes. However, in conditions such as established atherosclerosis, which can be considered a low-grade inflammatory state, E2 can destabilize atherosclerotic plaques by inducing molecules like MCP-1, matrix metalloproteinases (specifically MMP-2 and MMP-9), and TNF-α [41][42][43][44]. When atherosclerotic lesions are present, the altered expression of estrogen receptors on the vascular wall further exacerbates arterial wall damage [41,45].…”