GPER was Associated with Hypertension in Post-Menopausal Women

G protein-coupled estrogen receptor biased signaling in health and disease

G protein-coupled estrogen receptor (GPER) is now recognized for its pivotal role in cellular signaling, influencing diverse physiological processes and disease states. Unlike classical estrogen receptors, GPER exhibits biased signaling, wherein ligand binding triggers selective pathways over others, significantly impacting cellular responses. This review explores the nuanced mechanisms of biased signaling mediated by GPER, underscoring its relevance in cardiovascular health, neurological function, immune modulation, and oncogenic processes. Despite its critical implications, biased signaling through GPER remains underexplored compared to traditional signaling paradigms. We explore recent progress in understanding GPER signaling specificity and its potential therapeutic implications across various diseases. Future research directions aim to uncover the molecular basis of biased signaling, develop selective ligands, and translate these insights into personalized therapeutic approaches. Exploiting the therapeutic potential of GPER biased signaling represents a promising frontier in precision medicine, offering innovative strategies to address unmet medical needs.

Endothelin receptor B is required for the blood pressure-lowering effect of G protein-coupled estrogen receptor 1 in ovariectomized rats

Activation of G protein-coupled estrogen receptor 1 (GPER1) elicits antihypertensive actions in different animal models. The endothelin-1 signaling system plays a fundamental role in blood pressure regulation. Lack of functional endothelin receptor B (ETB) evokes hypertension and salt sensitivity. GPER1 and ETB interact to promote urinary sodium excretion in female rats. We hypothesized that activation of GPER1 protects against hypertension and salt sensitivity induced by ETB antagonism in female rats. Female Sprague-Dawley rats were implanted with radiotelemetry. Animals were then subjected to ovariectomy and simultaneously implanted with minipumps to deliver either the GPER1 agonist G1 or its corresponding vehicle. Two weeks post surgery, we initiated treatment of rats with the ETB antagonist A-192621. Animals were maintained on a normal-salt diet and then challenged with a high-salt diet for an additional 5 days. Assessment of mean arterial blood pressure revealed an increase in vehicle-treated, but not G1-treated, rats in response to ovariectomy. A-192621 increased blood pressure in normal-salt diet-fed vehicle- and G1-treated rats. G1 improved the circadian blood pressure rhythms that were disrupted in A-192621-treated ovariectomized rats. Thus, although systemic GPER1 activation did not protect ovariectomized rats from hypertension and salt sensitivity induced by ETB antagonism, it maintained circadian blood pressure rhythms. Functional ETB is required to elicit the antihypertensive actions of GPER1. Additional studies are needed to improve our understanding of the interaction between G protein-coupled receptors in regulating circadian blood pressure rhythm.NEW & NOTEWORTHY Systemic G protein-coupled estrogen receptor 1 (GPER1) activation in rats prevents the increase in blood pressure evoked by ovariectomy. Blockade of endothelin receptor B negates the blood pressure-lowering impact of GPER1 in ovariectomized rats. Endothelin receptor B plays an important role in mediating the blood pressure-lowering action of GPER1 activation in female rats.

The Role of G Protein-Coupled Estrogen Receptor (GPER) in Vascular Pathology and Physiology

OBJECTIVE

Estrogen is indispensable in health and disease and mainly functions through its receptors. The protection of the cardiovascular system by estrogen and its receptors has been recognized for decades. Numerous studies with a focus on estrogen and its receptor system have been conducted to elucidate the underlying mechanism. Although nuclear estrogen receptors, including estrogen receptor-α and estrogen receptor-β, have been shown to be classical receptors that mediate genomic effects, studies now show that GPER mainly mediates rapid signaling events as well as transcriptional regulation via binding to estrogen as a membrane receptor. With the discovery of selective synthetic ligands for GPER and the utilization of GPER knockout mice, significant progress has been made in understanding the function of GPER. In this review, the tissue and cellular localizations, endogenous and exogenous ligands, and signaling pathways of GPER are systematically summarized in diverse physiological and diseased conditions. This article further emphasizes the role of GPER in vascular pathology and physiology, focusing on the latest research progress and evidence of GPER as a promising therapeutic target in hypertension, pulmonary hypertension, and atherosclerosis. Thus, selective regulation of GPER by its agonists and antagonists have the potential to be used in clinical practice for treating such diseases.

Emerging Roles for G Protein-Coupled Estrogen Receptor 1 in Cardio-Renal Health: Implications for Aging

Cardiovascular (CV) and renal diseases are increasingly prevalent in the United States and globally. CV-related mortality is the leading cause of death in the United States, while renal-related mortality is the 8th. Despite advanced therapeutics, both diseases persist, warranting continued exploration of disease mechanisms to develop novel therapeutics and advance clinical outcomes for cardio-renal health. CV and renal diseases increase with age, and there are sex differences evident in both the prevalence and progression of CV and renal disease. These age and sex differences seen in cardio-renal health implicate sex hormones as potentially important regulators to be studied. One such regulator is G protein-coupled estrogen receptor 1 (GPER1). GPER1 has been implicated in estrogen signaling and is expressed in a variety of tissues including the heart, vasculature, and kidney. GPER1 has been shown to be protective against CV and renal diseases in different experimental animal models. GPER1 actions involve multiple signaling pathways: interaction with aldosterone and endothelin-1 signaling, stimulation of the release of nitric oxide, and reduction in oxidative stress, inflammation, and immune infiltration. This review will discuss the current literature regarding GPER1 and cardio-renal health, particularly in the context of aging. Improving our understanding of GPER1-evoked mechanisms may reveal novel therapeutics aimed at improving cardio-renal health and clinical outcomes in the elderly.

Signalling mechanisms in the cardiovascular protective effects of estrogen: With a focus on rapid/membrane signalling

In modern society, cardiovascular disease remains the biggest single threat to life, being responsible for approximately one third of worldwide deaths. Male prevalence is significantly higher than that of women until after menopause, when the prevalence of CVD increases in females until it eventually exceeds that of men. Because of the coincidence of CVD prevalence increasing after menopause, the role of estrogen in the cardiovascular system has been intensively researched during the past two decades in vitro, in vivo and in observational studies. Most of these studies suggested that endogenous estrogen confers cardiovascular protective and anti-inflammatory effects. However, clinical studies of the cardioprotective effects of hormone replacement therapies (HRT) not only failed to produce proof of protective effects, but also revealed the potential harm estrogen could cause. The "critical window of hormone therapy" hypothesis affirms that the moment of its administration is essential for positive treatment outcomes, pre-menopause (3-5 years before menopause) and immediately post menopause being thought to be the most appropriate time for intervention. Since many of the cardioprotective effects of estrogen signaling are mediated by effects on the vasculature, this review aims to discuss the effects of estrogen on vascular smooth muscle cells (VSMCs) and endothelial cells (ECs) with a focus on the role of estrogen receptors (ERα, ERβ and GPER) in triggering the more recently discovered rapid, or membrane delimited (non-genomic), signaling cascades that are vital for regulating vascular tone, preventing hypertension and other cardiovascular diseases.

Sex Hormones in Lymphedema

Simple Summary

Lymphedema is a life-long disease that affects a large number of patients treated for breast-, gynecological-, and urologic cancers in Western countries. Given that hormone levels are strongly modified in these conditions, and that patients widely undergo through hormone therapy, it is tempting to speculate that hormones might be key regulators in the maintenance of lymphedema. Despite an obvious prevalence for women, the role of sex hormones and gender has been poorly investigated in this pathology. This review aims to decipher how sex hormones interact with lymphatic vessels and whether hormone therapy could participate in lymphedema development.

Abstract

Lymphedema is a disorder of the lymphatic vascular system characterized by impaired lymphatic return resulting in swelling of the extremities and accumulation of undrained interstitial fluid/lymph that results in fibrosis and adipose tissue deposition in the limb. Whereas it is clearly established that primary lymphedema is sex-linked with an average ratio of one male for three females, the role of female hormones, in particular estrogens, has been poorly explored. In addition, secondary lymphedema in Western countries affects mainly women who developed the pathology after breast cancer and undergo through hormone therapy up to five years after cancer surgery. Although lymphadenectomy is identified as a trigger factor, the effect of co-morbidities associated to lymphedema remains elusive, in particular, estrogen receptor antagonists or aromatase inhibitors. In addition, the role of sex hormones and gender has been poorly investigated in the etiology of the pathology. Therefore, this review aims to recapitulate the effect of sex hormones on the physiology of the lymphatic system and to investigate whetherhormone therapy could promote a lymphatic dysfunction leading to lymphedema.

G protein-coupled estrogen receptor 1 as a novel regulator of blood pressure

The mechanisms underlying hypertension are multifaceted and incompletely understood. New evidence suggests that G protein-coupled estrogen receptor 1 (GPER1) mediates protective actions within the cardiovascular and renal systems. This mini-review focuses on recent advancements in our understanding of the vascular, renal, and cardiac GPER1-mediated mechanisms that influence blood pressure regulation. We emphasize clinical and basic evidence that suggests GPER1 as a novel target to aid therapeutic strategies for hypertension. Furthermore, we discuss current controversies and challenges facing GPER1-related research.

The Impact of Estrogen Receptor in Arterial and Lymphatic Vascular Diseases

The lower incidence of cardiovascular diseases in pre-menopausal women compared to men is well-known documented. This protection has been largely attributed to the protective effect of estrogens, which exert many beneficial effects against arterial diseases, including vasodilatation, acceleration of healing in response to arterial injury, arterial collateral growth and atheroprotection. More recently, with the visualization of the lymphatic vessels, the impact of estrogens on lymphedema and lymphatic diseases started to be elucidated. These estrogenic effects are mediated not only by the classic nuclear/genomic actions via the specific estrogen receptor (ER) α and β, but also by rapid extra-nuclear membrane-initiated steroid signaling (MISS). The ERs are expressed by endothelial, lymphatic and smooth muscle cells in the different vessels. In this review, we will summarize the complex vascular effects of estrogens and selective estrogen receptor modulators (SERMs) that have been described using different transgenic mouse models with selective loss of ERα function and numerous animal models of vascular and lymphatic diseases.