G-protein-coupled receptor 30 mediates the effects of estrogen on endothelial cell tube formation in vitro

GPR30 Inhibits Neuronal Apoptosis After Subarachnoid Hemorrhage by Activating the Wnt/β-Catenin Pathway in a m6A-dependent Manner

Neuronal apoptosis is associated with early brain injury after subarachnoid hemorrhage (SAH). In this study, the regulatory effects of GPR30 on neuronal apoptosis after SAH, METTL14 expression, and the Wnt/β-catenin pathway were investigated. SAH models were constructed in vitro in neurons and in vivo in rats. We found that the GPR30 protein was downregulated in OxyHB-stimulated neurons and SAH rat brain tissue. The GPR30 agonist G1 decreased iNOS levels and apoptosis in OxyHB-stimulated neurons. G1 increased m6A levels in OxyHB-stimulated neurons, increased the expression of METTL14 and Bcl-2, and reduced Caspase-3 and Bax levels. The GPR30 inhibitor G15 had the opposite effect as G1. METTL14 overexpression increased m6A levels in OxyHB-stimulated neurons; increased the expression of METTL14, Wnt1, β-catenin, and Bcl-2; decreased Caspase-3 and Bax levels; and inhibited apoptosis. The Wnt inhibitor IWR-1 abrogated the effects of METTL14 overexpression in OxyHB-stimulated neurons. In vivo, the results revealed that G1 decreased the mNSS, cerebral edema score, and caspase-3, IL-6, IL-1β, Bax, and p-β-catenin expression; inhibited apoptosis and nitric oxide production; and increased GPR30, IFN-γ, TGF-β1, METTL14, Wnt1, and β-catenin expression. G15 had the opposite effect of G1. METTL14 knockdown abrogated the effects of G1 in SAH model rats. Our results suggest that GPR30 inhibits neuronal apoptosis after SAH via Wnt/β-catenin pathway regulation and METTL14-mediated m6A modification, providing a new therapeutic target for SAH.

Estrogen receptors in mitochondrial metabolism: age-related changes and implications for pregnancy complications

Estrogen hormones are primarily associated with their role as female sex hormones responsible for primary and secondary sexual development. Estrogen receptors are known to undergo age-dependent decreases due to age-related changes in hormone production. In the mitochondria, estrogen functions by reducing the production of reactive oxygen species in the electron transport chain, inhibiting apoptosis, and regulating mitochondrial DNA content. Moreover, estrogen receptors may be the key components in maintaining mitochondrial membrane potential and structure. Although estrogen plays a crucial role in the development of pregnancy, our understanding of how estrogen receptors change with aging during pregnancy remains limited. During pregnancy, estrogen levels are significantly elevated, with a corresponding upregulation of estrogen receptors, which play various roles in pregnancy. However, the exact role of estrogen receptors in pregnancy complications remains to be further investigated. The paper reviews the role of estrogen receptors in the regulation of mitochondrial metabolism and in pregnancy complications, with a special focus on the effect of age-related changes on estrogen levels and estrogen receptors function. We also address how estrogen maintains mitochondrial function, including reducing the production of reactive oxygen species in the electron transport chain, inhibiting apoptosis, regulating mitochondrial DNA content, and maintaining mitochondrial membrane potential and structure. However, the effects of estrogen on mitochondria-endoplasmic reticulum contacts have not been well studied. Based on these emergent roles in mitochondria, the differential roles of estrogen receptors in pregnancy complications are of great relevance. The paper emphasizes the association between maternal health and estrogen receptors and indicates the need for future research to elucidate the interdependence of estrogen receptor-regulated maternal health with mitochondrial function and their relationship with the gut microbiome. Overall, we summarize the important role of estrogen receptors during pregnancy and highlight the need for further research to better understand the role of estrogen receptors in aging and pregnancy complications. This not only helps to reveal the mechanism underlying the role of estrogen in maternal health but also has potential clinical implications for the development of new therapies targeting age-related diseases and pregnancy complications.

GPER deficiency impedes murine myocutaneous revascularization and wound healing

Estrogens regulate numerous physiological and pathological processes, including wide-ranging effects in wound healing. The effects of estrogens are mediated through multiple estrogen receptors (ERs), including the classical nuclear ERs (ERα and ER β ), that typically regulate gene expression, and the 7-transmembrane G protein-coupled estrogen receptor (GPER), that predominantly mediates rapid "non-genomic" signaling. Estrogen modulates the expression of various genes involved in epidermal function and regeneration, inflammation, matrix production, and protease inhibition, all critical to wound healing. Our previous work demonstrated improved myocutaneous wound healing in female mice compared to male mice. In the current study, we employed male and female GPER knockout mice to investigate the role of this estrogen receptor in wound revascularization and tissue viability. Using a murine myocutaneous flap model of graded ischemia, we measured real-time flap perfusion via laser speckle perfusion imaging. We conducted histologic and immunohistochemical analyses to assess skin and muscle viability, microvascular density and vessel morphology. Our results demonstrate that GPER is crucial in wound healing, mediating effects that are both dependent and independent of sex. Lack of GPER expression is associated with increased skin necrosis, reduced flap perfusion and altered vessel morphology. These findings contribute to understanding GPER signaling in wound healing and suggest possible therapeutic opportunities by targeting GPER.

Soybean isoflavone promotes milk yield and milk fat yield through the ERα-mediated Akt/mTOR pathway in dairy goats

Soybean isoflavone (SIF) in soybeans are natural phytoestrogens, which is functioned as an estrogen agonistic or antagonistic. SIF regulates the capacity of animals to synthesize triacylglycerols by directly utilizing long-chain fatty acids. However, few studies have focused on its regulatory lipid metabolism in lactating dairy goats. The objective of this study was to investigate the influence of SIF on milk yield and composition using Saanen dairy goats as a model, employing both in vivo and in vitro approaches. In the in vivo phase, a total of 20 goats were randomly divided into 2 groups: the control group fed a basal diet, and the experimental group fed a basal diet supplemented with SIF at a dosage of 100 mg/d. The results underscored a significant elevation in serum estrogen and prolactin levels in the SIF-supplemented group (P < 0.05). Notably, SIF supplementation also displayed a higher milk fat percentage (P = 0.03). Transitioning to in vitro experimentation, the addition of SIF (75 µM) to goat mammary epithelial cells exhibited a pronounced effect on cell proliferation. It spurred cell proliferation and led to an increase in triacylglycerol levels (P < 0.05). Consistently, SIF showcased an enhancement in the expression of key genes associated with milk fat de novo synthesis. SIF demonstrated a rescuing effect on the suppressive impact of MK2206 on Akt protein phosphorylation. Importantly, the study observed that the knockdown of estrogen receptor alpha (ERα) expression completely counteracted the effect of SIF on lipid droplet accumulation. Collectively, the current study establishes the critical role of SIF in process of fatty acid de novo in the goat mammary gland. This regulation is notably mediated through the ERα-Akt axis, thus enriching our understanding of this intricate biological process. This research sheds light on the potential benefits of SIF supplementation in dairy goat farming, ultimately contributing to improved milk production and quality.

GPER involvement in inflammatory pain

Chronic pain is a worldwide refractory health disease that causes major financial and emotional burdens and that is devastating for individuals and society. One primary source of pain is inflammation. Current treatments for inflammatory pain are weakly effective, although they usually replace analgesics, such as opioids and non-steroidal anti-inflammatory drugs, which display serious side effects. Emerging evidence indicates that the membrane G protein-coupled estrogen receptor (GPER) may play an important role in the regulation of inflammation and pain. Herein, we focus on the consequences of pharmacological and genetic GPER modulation in different animal models of inflammatory pain. We also provide a brief overview of the putative mechanisms including the direct action of GPER on pain transmission and inflammation.

The Relationship between Cadmium Exposure and Mortality in Postmenopausal Females: A Cohort Study of 2001-2018 NHANES

Cadmium is one of the most harmful elements to human health, and the health of postmenopausal females is an important public health issue. However, the correlation between exposure to cadmium and the survival status of postmenopausal women is currently not fully clear. This research intended to explore the correlation between cadmium exposure and mortality among postmenopausal females using a representative sample of the population in the U.S. We drew upon the data of the National Health and Nutrition Examination Survey (2001-2018). Cox's proportional hazards models and a restricted cubic spline regression (RCS) model were utilized to analyze the correlation between blood and urine cadmium and the mortality of postmenopausal women. Stratified analyses also were conducted to identify the highest risk factor of mortality for the participants. The mean concentration of blood cadmium was 0.59 μg/L, and the mean concentration of urine cadmium was 0.73 μg/g creatinine. Higher cadmium concentrations in blood and urine were significantly related to an increase in all-cause mortality for postmenopausal females after adjustment for multivariate covariates. Furthermore, there was a linear positive correlation between urine cadmium concentrations and cancer mortality, while there was no correlation between blood cadmium and cancer death. The correlation between cadmium concentrations and all-cause mortality is stronger in older, more overweight women with a history of hypertension or smoking. We propose that cadmium remains an important risk factor of all-cause and cancer mortality among postmenopausal females in the U.S. Further decreases in cadmium exposure in the population can promote the health of postmenopausal women and prolong their lifespan.

GPER: An Estrogen Receptor Key in Metastasis and Tumoral Microenvironments

Estrogens and their role in cancer are well-studied, and some cancer types are classified in terms of their response to them. In recent years, a G protein-coupled estrogen receptor (GPER) has been described with relevance in cancer. GPER is a pleiotropic receptor with tissue-specific activity; in normal tissues, its activation is related to correct development and homeostasis, while in cancer cells, it can be pro- or anti-tumorigenic. Also, GPER replaces estrogen responsiveness in estrogen receptor alpha (ERα)-lacking cancer cell lines. One of the most outstanding activities of GPER is its role in epithelial-mesenchymal transition (EMT), which is relevant for metastasis development. In addition, the presence of this receptor in tumor microenvironment cells contributes to the phenotypic plasticity required for the dissemination and maintenance of tumors. These characteristics suggest that GPER could be a promising therapeutic target for regulating cancer development. This review focuses on the role of GPER in EMT in tumorigenic and associated cells, highlighting its role in relation to the main hallmarks of cancer and possible therapeutic options.

Gender differences in GRK2 in cardiovascular diseases and its interactions with estrogen

G protein-coupled receptor kinase 2 (GRK2) is a multifunctional protein involved in regulating G protein-coupled receptor (GPCR) and non-GPCR signaling in the body. In the cardiovascular system, increased expression of GRK2 has been implicated in the occurrence and development of several cardiovascular diseases (CVDs). Recent studies have found gender differences in GRK2 in the cardiovascular system under physiological and pathological conditions, where GRK2's expression and activity are increased in males than in females. The incidence of CVDs in premenopausal women is lower than in men of the same age, which is related to estrogen levels. Given the shared location of GRK2 and estrogen receptors, estrogen may interact with GRK2 by modulating vital molecules such as calmodulin (CaM), caveolin, RhoA, nitrate oxide (NO), and mouse double minute 2 homolog (Mdm2), via signaling pathways mediated by estrogen's genomic (ERα and ERβ), and non-genomic (GPER) receptors, conferring cardiovascular protection in females. Highlighting the gender differences in GRK2 and understanding its interaction with estrogen in the cardiovascular system is pertinent in treating gender-related CVDs. As a result, this article explores the gender differences of GRK2 in the cardiovascular system and its relationship with estrogen during disease conditions. Estrogen's protective and therapeutic effects and its mechanism on GRK2-related cardiovascular diseases have also been discussed.

Aquaporin-8 overexpression is involved in vascular structure and function changes in placentas of gestational diabetes mellitus patients

To study the role and mechanism of aquaporin-8 (AQP8) in placental vascular development in gestational diabetes mellitus (GDM), hematoxylin–eosin staining and immunohistochemistry were utilized to analyze the histopathological changes in placentas in GDM patients. Transwell, CCK-8, and tube formation assays were performed to examine cell migration, proliferation, and tube formation. AQP8, vascular cell adhesion molecule 1 (VCAM-1), tumor necrosis factor alpha (TNF)-α, and vascular endothelial growth factor (VEGF)-A expression levels were investigated. Relative to the control group, the placentas in the GDM group showed morphological changes, the number of microvessels in the placental villi arterioles was significantly higher, and the area of microvessels in the arterioles of placental villi was significantly lower. The expression levels of VCAM-1, TNF-α, VEGF-A, and AQP8 in the GDM placentas and human umbilical vein endothelial cells (HUVECs) stimulated by high glucose were significantly higher than those in the control group, and AQP8 was located in placental endothelial cells. Overexpression of glucose and AQP8 inhibited tube formation, migration, and proliferation in HUVECs. High glucose levels can induce dysfunction in vascular endothelial cells and lead to pathological changes in the placental vascular structure in GDM. AQP8 overexpression in placental GDM can inhibit endothelial cell behavior, cause endothelial cell dysfunction, and further participate in the occurrence and development of GDM placental vascular lesions.

Hormone Therapy: A Potential Risk Factor Affecting Survival and Functional Restoration of Transplanted Lymph Nodes

Background: Transplantation of lymph nodes (LNs) is an increasingly popular option for treating lymphedema. Increasing evidence indicates an intrinsic correlation between estrogen signaling and the lymphatic system. We explored the effects of 17β estradiol and antiestrogen treatment (tamoxifen) on the survival and functional restoration of transplanted popliteal lymph nodes (PLNs).

Methods: A total of forty-eight ovariectomized mice were divided into three groups of 16: OVX + E2 (treated with 17β-estradiol), OVX + TMX (treated with tamoxifen), and OVX (control; treated with olive oil as a solvent). After 2 weeks, PLNs were transplanted. Then, reconnections of lymphatic vessels were observed, and the morphology and survival of transplanted PLNs were evaluated 4 weeks after transplantation. T cells, B cells, lymphatic vessels, and high endothelial venules (HEVs) were subjected to immunofluorescence staining or immunohistochemical staining and quantified.

Results: The percentage of lymphatic reconnections was 93.75% in the OVX + E2 group, 68.75% in the OVX + TMX group, and 75% in the OVX group. Surviving PLNs were observed in 16 of 16 in the OVX + E2 group, seven of 16 in the OVX + TMX group, and 13 of 16 in the OVX group. The mean size of PLNs in the largest cross section of the OVX + TMX group was significantly lower than that in the other groups. The distributions of B cells and T cells in surviving PLNs were similar to those in normal LNs. The ratio of dilated HEVs/total HEVs and density of lymphatic vessels in the OVX + E2 group were the highest among the three groups, whereas the lowest ratio and density were observed in the OVX + TMX group.

Conclusion: Tamoxifen treatment might lead to cellular loss of transplanted LNs and interfere with the structural reconstruction and functional restoration, thereby inhibiting the survival of transplanted PLNs. Estrogen treatment facilitated the maintenance and regeneration of functional HEVs as well as lymphangiogenesis.

Fetoplacental vasculature as a model to study human cardiovascular endocrine disruption

Increasing evidence has associated the exposure of endocrine-disrupting chemicals (EDCs) with the cardiovascular (CV) system. This exposure is particularly problematic in a sensitive window of development, pregnancy. Pregnancy exposome can affect the overall health of the pregnancy by dramatic changes in vascular physiology and endocrine activity, increasing maternal susceptibility. Moreover, fetoplacental vascular function is generally altered, increasing the risk of developing pregnancy complications (including cardiovascular diseases, CVD) and predisposing the foetus to adverse health risks later in life. Thus, our review summarizes the existing literature on exposures to EDCs during pregnancy and adverse maternal health outcomes, focusing on the human placenta, vein, and umbilical artery associated with pregnancy complications. The purpose of this review is to highlight the role of fetoplacental vasculature as a model for the study of human cardiovascular endocrine disruption. Therefore, we emphasize that the placenta, together with the umbilical arteries and veins, allows a better characterization of the pregnant woman's exposome. Consequently, it contributes to the protection of the mother and foetus against CV disorders in life.

Predominance of Heart Failure With Preserved Ejection Fraction in Postmenopausal Women: Intra- and Extra-Cardiomyocyte Maladaptive Alterations Scaffolded by Estrogen Deficiency

Heart failure (HF) remains a public health concern as it is associated with high morbidity and death rates. In particular, heart failure with preserved ejection fraction (HFpEF) represents the dominant (>50%) form of HF and mostly occurring among postmenopausal women. Hence, the initiation and progression of the left ventricular diastolic dysfunctions (LVDD) (a typically clinical manifestation of HFpEF) in postmenopausal women have been attributed to estrogen deficiency and the loss of its residue cardioprotective effects. In this review, from a pathophysiological and immunological standpoint, we discuss the probable multiple pathomechanisms resulting in HFpEF, which are facilitated by estrogen deficiency. The initial discussions recap estrogen and estrogen receptors (ERs) and β-adrenergic receptors (βARs) signaling under physiological/pathological states to facilitate cardiac function/dysfunction, respectively. By reconciling these prior discussions, attempts were made to explain how the loss of estrogen facilitates the disruptions both ERs and βARs-mediated signaling responsible for; the modulation of intra-cardiomyocyte calcium homeostasis, maintenance of cardiomyocyte cytoskeletal and extracellular matrix, the adaptive regulation of coronary microvascular endothelial functions and myocardial inflammatory responses. By scaffolding the disruption of these crucial intra- and extra-cardiomyocyte physiological functions, estrogen deficiency has been demonstrated to cause LVDD and increase the incidence of HFpEF in postmenopausal women. Finally, updates on the advancements in treatment interventions for the prevention of HFpEF were highlighted.

Long noncoding TUG1 promotes angiogenesis of HUVECs in PE via regulating the miR-29a-3p/VEGFA and Ang2/Tie2 pathways

BACKGROUND

Preeclampsia (PE) is a pregnancy-specific disease that is associated with oxidative stress-induced endothelial dysfunction. Long noncoding RNAs (lncRNAs) are related to PE progression. The purpose is to study whether lncRNA taurine-upregulated gene 1 (TUG1) takes part in endothelial dysfunction in PE.

METHODS

The placenta tissues were collected from PE patients and normal subjects. Human umbilical vein endothelial cells (HUVECs) were suffered from hypoxia-reoxygenation (H/R). TUG1, miR-29a-3p and vascular endothelial growth factor A (VEGFA) were detected via qRT-PCR. soluble fms-related tyrosine kinase-1 (sFLT1) and soluble endoglin (sENG) levels were detected by ELISA. Cell proliferation, migration, invasion and angiogenesis were examined via MTT, wound healing analysis, transwell and tube formation analysis. The proteins in VEGFA and angiopoietin 2 (Ang2)/tyrosine kinase with immunoglobulin-like and EGF-like domains 2 (Tie2) signaling were measured by western blot. The binding relationship was analyzed via Starbase, Jefferson and dual-luciferase reporter analysis.

RESULTS

TUG1 and VEGFA levels were downregulated, and levels of miR-29a-3p, sFLT1 and sENG were increased in PE patients. TUG1 abundance was reduced in H/R-stimulated HUVECs, and TUG1 overexpression increased proliferation, migration, invasion and angiogenesis, and activated the VEGFA and Ang2/Tie2 signaling in H/R-stimulated HUVECs. TUG1 sponged miR-29a-3p, and miR-29a-3p overexpression reversed the function of TUG1 on H/R-induced HUVECs dysfunction. MiR-29a-3p knockdown attenuated H/R-induced inhibition of proliferation, migration, invasion, angiogenesis and activation of the VEGFA and Ang2/Tie2 signaling in HUVECs. VEGFA and Ang2 were targeted by miR-29a-3p, and VEGFA or Ang2 silence weakened the role of miR-29a-3p knockdown in H/R-caused HUVECs dysfunction.

CONCLUSION

TUG1 facilitates proliferation, migration, invasion and angiogenesis in H/R-stimulated HUVECs via activating the VEGFA and Ang2/Tie2 signaling by regulating miR-29a-3p.

Estrogen and Preeclampsia: Potential of Estrogens as Therapeutic Agents in Preeclampsia

There is a significant decline in the estrogen levels in preeclampsia, and exogenous administration of estradiol normalizes blood pressure and other associated symptoms of preeclampsia. The decrease in estrogen levels may be due to changes in enzyme activities of hydroxysteroid (17-β) dehydrogenase 1, aromatase, and COMT. There is also a decrease in the novel, estrogenic G-protein-coupled receptor 30 (GPR30) in the placental trophoblast cells in preeclampsia. The activation of GPR30 protects the placenta from hypoxia-reoxygenation injury, decreases apoptosis and increases proliferation through eNOS and PI3K-Akt signaling pathways. Estrogens may also increase Ca²⁺-activated K⁺ channel function, decrease the release of inflammatory cytokines, and oxidative stress to improve placental perfusion. Both preclinical and clinical studies show the decrease in the 2-methoxyestradiol levels in preeclampsia, which may be due to a decrease in estradiol itself along with a decrease in the enzymatic actions of the COMT enzyme. 2-Methoxyestradiol activates HIF1α and vascular endothelial growth factor receptors (VEGFR-2) to maintain placental perfusion by increasing angiogenesis. The present review discusses the preclinical and clinical studies describing the role of estrogen in preeclampsia along with possible mechanisms.

Activation of GPR30 with G1 inhibits oscillatory shear stress-induced adhesion of THP-1 monocytes to HAECs by increasing KLF2

Atherosclerosis is a chronic inflammatory disease known to be mediated by numerous factors, among which endothelial dysfunction plays a critical role. Oscillatory shear stress induces endothelial cells to lose their anti-atherosclerotic properties and downregulates the expression of the innate protective transcription factor, Krüppel-like factor 2 (KLF2), which is typically upregulated in vascular endothelial cells in response to harmful stimuli. Oxidative stress and inflammation impair endothelial function and damage their survival. Oscillatory shear stress also promotes generation of reactive oxygen species and production of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), thereby further promoting endothelial dysfunction and formation of atherosclerotic plaque. A major event in the development of atherosclerotic plaque is rolling and adhesion of monocytes to endothelial cells, which is mediated by adhesion molecules including vascular cellular adhesion molecule 1 and endothelial-selectin. Expression of these molecules is also upregulated by oscillatory shear stress. Estrogen has long been recognized as a protective agent against atherosclerosis, but the mechanisms through which estrogen receptors prevent atherogenesis remain unclear. In the present study, we investigated the role of the G-coupled protein estrogen receptor (GPR30) in oscillatory shear stress- induced endothelial dysfunction. We show that agonism of GPR30 by its specific agonist G1 prevented oscillatory shear stress -induced oxidative stress markers and production of inflammatory cytokines and adhesion molecules. As a result, GPR30 activation suppresses monocytes adhesion to endothelial cells. Furthermore, we demonstrate that GPR30 prevents oscillatory shear stress- induced downregulation of KLF2 via ERK5 pathway. These findings suggest that endothelial GPR30 is potential target to suppress oscillatory shear stress mediated atherogenesis.

Clinical Efficacy and Safety of Angiogenesis Inhibitors: Sex Differences and Current Challenges

Vasoactive molecules, such as vascular endothelial growth factor (VEGF) and endothelins, share cytokine-like activities and regulate endothelial cell (EC) growth, migration and inflammation. Some endothelial mediators and their receptors are targets for currently approved angiogenesis inhibitors, drugs that are either monoclonal antibodies raised towards VEGF, or inhibitors of vascular receptor protein kinases and signaling pathways. Pharmacological interference with the protective functions of ECs results in a similar spectrum of adverse effects. Clinically, the most common side effects of VEGF signaling pathway inhibition include an increase in arterial pressure, left ventricular (LV) dysfunction ultimately causing heart failure, and thromboembolic events, including pulmonary embolism, stroke, and myocardial infarction. Sex steroids such as androgens, progestins, and estrogen and their receptors (ERα, ERβ, GPER; PR-A, PR-B; AR) have been identified as important modifiers of angiogenesis, and sex differences have been reported for anti-angiogenic drugs. This review article discusses the current challenges clinicians are facing with regard to angiogenesis inhibitor treatments, including the need to consider sex differences affecting clinical efficacy and safety. We also propose areas for future research taking into account the role of sex hormone receptors and sex chromosomes. Development of new sex-specific drugs with improved target and cell-type selectivity likely will open the way personalized medicine in men and women requiring antiangiogenic therapy and result in reduced adverse effects and improved therapeutic efficacy.

Estrogen and calcium handling proteins: new discoveries and mechanisms in cardiovascular diseases

Estrogen deficiency is considered to be an important factor leading to cardiovascular diseases (CVDs). Indeed, the prevalence of CVDs in postmenopausal women exceeds that of premenopausal women and men of the same age. Recent research findings provide evidence that estrogen plays a pivotal role in the regulation of calcium homeostasis and therefore fine-tunes normal cardiomyocyte contraction and relaxation processes. Disruption of calcium homeostasis is closely associated with the pathological mechanism of CVDs. Thus, this paper maps out and summarizes the effects and mechanisms of estrogen on calcium handling proteins in cardiac myocytes, including L-type Ca²⁺ channel, the sarcoplasmic reticulum Ca²⁺ release channel named ryanodine receptor, sarco(endo)plasmic reticulum Ca²⁺-ATPase, and sodium-calcium exchanger. In so doing, we provide theoretical and experimental evidence for the successful design of estrogen-based prevention and treatment therapies for CVDs.

G protein-coupled estrogen receptor activation improves contractile and diastolic functions in rat renal interlobular artery to protect against renal ischemia reperfusion injury

OBJECTIVE

This work aimed to investigate whether G protein-coupled estrogen receptor (GPER) can improve the renal interlobular artery vascular function by increasing the NO content, thereby protecting against renal ischemia-reperfusion (IR) injury.

METHODS

This study classified ovariectomised (OVX) female Sprague-Dawley rats into OVX, OVX + IR, OVX + IR + G1 (the GPER agonist G1), OVX + IR + G1+G15 (GPER blocker) and OVX + IR + G1+L-NAME (eNOS blocker) groups. Enzyme-linked immunosorbent assay was performed to detect the estrogen levels in the body and eliminate interference from endogenous estrogens. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labelling (TUNEL) and HE staining, renal function test and Paller scoring were performed to identify the successful model and detect the degree of renal and renal interlobular arteries injury. The in vitro microvascular pressure diameter measurement technique was used to detect the contraction and diastolic activities of the renal interlobular arteries in each group. Immunofluorescence technique was used to observe the localisation and expression levels of GPER and eNOS in renal interlobular arteries. The GPER and eNOS protein expression levels in each group were detected by Western blot. The NO content in the serum of each group was detected by the nitrate reductase method.

RESULT

After OVX, the estrogen level in the body decreased significantly (P < 0.01), and TUNEL staining showed a significant increase in the degree of renal tubular epithelial cell apoptosis in the IR group. Serum creatinine (SCr) and blood urea nitrogen (BUN) levels were significantly increased in the IR group (P < 0.01), and the Paller score showed significantly increased kidney damage. When performing drug treatment, the G1 intervention group significantly decreased serum BUN and SCr levels after IR injury (P < 0.01). The Paller score showed significantly decreased the degree of renal injury (P < 0.01). After IR, the renal interlobular artery contraction rate and systolic velocity of blood vessels were significantly decreased (P < 0.01). The G1 intervention group significantly restored contraction rate and systolic velocity of blood vessels (P < 0.01), and G15 and L-NAME partially reversed this effect (P < 0.01). Immunofluorescence technique showed that GPER was expressed in renal interlobular artery smooth muscle and endothelial cells. After IR injury, the GPER protein expression increased, and the eNOS protein expression decreased significantly (P < 0.01). Western blot showed that after IR injury, the GPER protein expression increased, and the eNOS protein expression decreased significantly. After G1 intervention, the GPER content did not change, and the eNOS content increased significantly (P < 0.01). After ischemia and reperfusion, the serum NO content decreased significantly, but it increased after G1 intervention. G15 and L-NAME reversed the effects of G1 to varying degrees (both at P < 0.01).

CONCLUSION

GPER may improve the renal interlobular artery vascular function by increasing the NO content, thereby protecting against renal IR injury.

CD90 determined two subpopulations of glioma-associated mesenchymal stem cells with different roles in tumour progression

Human glioma-associated mesenchymal stem cells (gbMSCs) are the stromal cell components that contribute to the tumourigenesis of malignant gliomas. Recent studies have shown that gbMSCs consist of two distinct subpopulations (CD90⁺ and CD90⁻ gbMSCs). However, the different roles in glioma progression have not been expounded. In this study, we found that the different roles of gbMSCs in glioma progression were associated with CD90 expression. CD90^high gbMSCs significantly drove glioma progression mainly by increasing proliferation, migration and adhesion, where as CD90^low gbMSCs contributed to glioma progression chiefly through the transition to pericytes and stimulation of vascular formation via vascular endothelial cells. Furthermore, discrepancies in long non-coding RNAs and mRNAs expression were verified in these two gbMSC subpopulations, and the potential underlying molecular mechanism was discussed. Our data confirm for the first time that CD90^high and CD90^low gbMSCs play different roles in human glioma progression. These results provide new insights into the possible future use of strategies targeting gbMSC subpopulations in glioma patients.

A current view of G protein-coupled receptor - mediated signaling in pulmonary hypertension: finding opportunities for therapeutic intervention

Pathological vascular remodeling is observed in various cardiovascular diseases including pulmonary hypertension (PH), a disease of unknown etiology that has been characterized by pulmonary artery vasoconstriction, right ventricular hypertrophy, vascular inflammation, and abnormal angiogenesis in pulmonary circulation. G protein-coupled receptors (GPCRs) are the largest family in the genome and widely expressed in cardiovascular system. They regulate all aspects of PH pathophysiology and represent therapeutic targets. We overview GPCRs function in vasoconstriction, vasodilation, vascular inflammation-driven remodeling and describe signaling cross talk between GPCR, inflammatory cytokines, and growth factors. Overall, the goal of this review is to emphasize the importance of GPCRs as critical signal transducers and targets for drug development in PH.

MiR-148b-3p inhibits renal carcinoma cell growth and pro-angiogenic phenotype of endothelial cell potentially by modulating FGF2

MicroRNAs (miRNAs) have been implicated in a large number of biological processes such as tumor angiogenesis. MiR-148b-3p has been identified as a tumor suppressor in multiple cancer types and the function of miR-148b-3p in renal carcinoma remains unidentified. In this study, we found that the expression of miR-148b-3p was decreased in renal carcinoma based on GEO analysis and the gain-of-function experiments revealed that miR-148b-3p promoted renal carcinoma cell apoptosis and suppressed cell proliferation, migration in vitro and tumor growth in vivo. Functionally, the tube formation, invasion and migration capabilities of human umbilical vein endothelial cells (HUVECs) were suppressed by conditioned media derived from renal carcinoma 786-O cells that were transfected with miR-148b-3p mimics. Meanwhile, these conditioned media inhibited the proliferation and promoted apoptosis of HUVECs. The key angiogenesis inducer hypoxia inducible factor-1α (HIF-1α) and the pro-angiogenic mediators were decreased in 786-O cells that were transfected with miR-148b-3p mimics. Mechanistically, miR-148b-3p could target fibroblast growth factor-2 (FGF2) and further impaired the activation of fibroblast growth factor receptor 2 (FGFR2). Taken together, our findings demonstrate that miR-148b-3p attenuates renal carcinoma cell growth, the invasion and tube formation of endothelial cell potentially via regulating FGF2-FGFR2 signaling pathway.

Effects of 17β-Estradiol on Mitophagy in the Murine MC3T3-E1 Osteoblast Cell Line is Mediated via G Protein-Coupled Estrogen Receptor and the ERK1/2 Signaling Pathway

Background

Osteoporosis is associated with 17β-estradiol deficiency. The G protein-coupled receptor 30 (GPR30) is known to be an estrogen-responsive receptor, but its role in the degradation of mitochondria in osteoblasts by autophagy, or mitophagy, remains unclear. The aim of this in vitro study was to evaluate the effects of 17β-estradiol, GPR30, and its signaling pathway, on mitophagy in the murine MC3T3-E1 osteoblast cell line.

Material/Methods

In the murine MC3T3-E1 osteoblast cell line, cells were treated with 17β-estradiol, or G15, a selective GPR30 antagonist, or U0126, a mitogen-activated protein (MAP) kinase (ERK1/2) inhibitor, or with vehicle as control. The expression of GPR30 was determined by Western blot, reverse transcription-polymerase chain reaction (RT-PCR), and confocal immunofluorescence imaging. Cell morphology and mitochondrial autophagosomes were identified using transmission electron microscopy (TEM). Phosphorylation of the mitophagy markers, heat shock protein 60 (Hsp60), translocase of outer membrane (Tom)20, and microtubule-associated protein 1A/1B-light chain 3 (LC3) were determined by Western blot, and cell proliferation was determined using the bromodeoxyuridine (BrdU) assay.

Results

The optimum concentration of 17β-estradiol that resulted in GPR30 expression in MC3T3-E1 cells was 10⁻⁷ M, which led to the accumulation of mitochondrial autophagosomes and increased protein phosphorylation levels of Hsp60, Tom20, and LC3. In cells pretreated with G15 or U0126, 17β-estradiol treatment did not increase mitophagy in MC3T3-E1 cells.

Conclusions

In murine osteoblasts cultured in vitro, treatment with 17β-estradiol resulted in the expression of GPR30 and enhanced mitophagy through the GPR30 and ERK1/2 signaling pathway.

The protective role of estrogen and estrogen receptors in cardiovascular disease and the controversial use of estrogen therapy

Epidemiologic studies have previously suggested that premenopausal females have reduced incidence of cardiovascular disease (CVD) when compared to age-matched males, and the incidence and severity of CVD increases postmenopause. The lower incidence of cardiovascular disease in women during reproductive age is attributed at least in part to estrogen (E2). E2 binds to the traditional E2 receptors (ERs), estrogen receptor alpha (ERα), and estrogen receptor beta (ERβ), as well as the more recently identified G-protein-coupled ER (GPR30), and can exert both genomic and non-genomic actions. This review summarizes the protective role of E2 and its receptors in the cardiovascular system and discusses its underlying mechanisms with an emphasis on oxidative stress, fibrosis, angiogenesis, and vascular function. This review also presents the sexual dimorphic role of ERs in modulating E2 action in cardiovascular disease. The controversies surrounding the clinical use of exogenous E2 as a therapeutic agent for cardiovascular disease in women due to the possible risks of thrombotic events, cancers, and arrhythmia are also discussed. Endogenous local E2 biosynthesis from the conversion of testosterone to E2 via aromatase enzyme offers a novel therapeutic paradigm. Targeting specific ERs in the cardiovascular system may result in novel and possibly safer therapeutic options for cardiovascular protection.