Role of estrogen in angiogenesis in cardiovascular diseases

High estrogen induces trans-differentiation of vascular smooth muscle cells to a macrophage-like phenotype resulting in aortic inflammation via inhibiting VHL/HIF1a/KLF4 axis

Estrogen is thought to have a role in slowing down aging and protecting cardiovascular and cognitive function. However, high doses of estrogen are still positively associated with autoimmune diseases and tumors with systemic inflammation. First, we administered exogenous estrogen to female mice for three consecutive months and found that the aorta of mice on estrogen develops inflammatory manifestations similar to Takayasu arteritis (TAK). Then, in vitro estrogen intervention was performed on mouse aortic vascular smooth muscle cells (MOVAS cells). Stimulated by high concentrations of estradiol, MOVAS cells showed decreased expression of contractile phenotypic markers and increased expression of macrophage-like phenotypic markers. This shift was blocked by tamoxifen and Krüppel-like factor 4 (KLF4) inhibitors and enhanced by Von Hippel-Lindau (VHL)/hypoxia-inducible factor-1α (HIF-1α) interaction inhibitors. It suggests that estrogen-targeted regulation of the VHL/HIF-1α/KLF4 axis induces phenotypic transformation of vascular smooth muscle cells (VSMC). In addition, estrogen-regulated phenotypic conversion of VSMC to macrophages is a key mechanism of estrogen-induced vascular inflammation, which justifies the risk of clinical use of estrogen replacement therapy.

Risk Factors for the Recurrence of Chronic Subdural Hematoma

Objective

Chronic subdural hematoma (CSDH) is commonly encountered in neurosurgery, and often occurs in elderly patients following a head injury. Despite favorable postoperative prognosis, recurrence remains common. Herein, we retrospectively analyzed the clinical and radiological data of patients at our institute to identify the risk factors for CSDH recurrence.

Methods

We investigated 370 patients who underwent surgery for CSDH at our institute. The following data were analyzed: sex, age, antiplatelet/anticoagulant use, preexisting diseases, radiological parameters, and surgical techniques. A univariate analysis was subsequently performed to examine the association between these variables and CSDH recurrence. Variables with a p-value of <0.05 in univariate analysis were further subjected to a multivariate logistic regression model to identify independent risk factors of CSDH.

Results

Of the 370 patients, 345 (93.2%) had no recurrence and 25 (6.8%) had recurrence. Univariate and multivariate analyses revealed that male sex, advanced age, bilateral hematoma, moderate or severe brain atrophy, separation type, gradation type, and burr hole trephination were independent risk factors for CSDH recurrence.

Conclusion

Sex, age, bilateral hematoma, brain atrophy, hematoma density and architecture, and surgical techniques are all associated with CSDH recurrence.

Reprogramming of endothelial gene expression by tamoxifen inhibits angiogenesis and ERα-negative tumor growth

Rationale: 17β-estradiol (E2) can directly promote the growth of ERα-negative cancer cells through activation of endothelial ERα in the tumor microenvironment, thereby increasing a normalized tumor angiogenesis. ERα acts as a transcription factor through its nuclear transcriptional AF-1 and AF-2 transactivation functions, but membrane ERα plays also an important role in endothelium. The present study aims to decipher the respective roles of these two pathways in ERα-negative tumor growth. Moreover, we delineate the actions of tamoxifen, a Selective Estrogen Receptor Modulator (SERM) in ERα-negative tumors growth and angiogenesis, since we recently demonstrated that tamoxifen impacts vasculature functions through complex modulation of ERα activity. Methods: ERα-negative B16K1 cancer cells were grafted into immunocompetent mice mutated for ERα-subfunctions and tumor growths were analyzed in these different models in response to E2 and/or tamoxifen treatment. Furthermore, RNA sequencings were analyzed in endothelial cells in response to these different treatments and validated by RT-qPCR and western blot. Results: We demonstrate that both nuclear and membrane ERα actions are required for the pro-tumoral effects of E2, while tamoxifen totally abrogates the E2-induced in vivo tumor growth, through inhibition of angiogenesis but promotion of vessel normalization. RNA sequencing indicates that tamoxifen inhibits the E2-induced genes, but also initiates a specific transcriptional program that especially regulates angiogenic genes and differentially regulates glycolysis, oxidative phosphorylation and inflammatory responses in endothelial cells. Conclusion: These findings provide evidence that tamoxifen specifically inhibits angiogenesis through a reprogramming of endothelial gene expression via regulation of some transcription factors, that could open new promising strategies to manage cancer therapies affecting the tumor microenvironment of ERα-negative tumors.

Angiogenic Activity and Mechanism for Bisphenols on Endothelial Cell and Mouse: Evidence of a Structural-Selective Effect

Increased epidemiological evidence indicates the association of bisphenol exposure with human vascular disorders, while the underlying mechanism has not been clarified. Here, we sought to unveil the potential angiogenic effect and the underlying mechanism of bisphenols with different structural features using endothelial cells treated with an environmentally relevant concentration of bisphenols (range: 1 nM to 10 μM) and a C57BL/6 mouse model fed with doses of 0.002, 0.02, 2, and 20 mg/kg BW/day for 5 weeks. Bisphenol A (BPA) and bisphenol S (BPS) at a 1 nM level significantly increased tube formation by 45.1 and 30.2% and induced the microvessel sprouting, while tube length and microvessel sprouting were significantly inhibited by 37.2 and 55.7% after exposure to tetrabromobisphenol S (TBBPS) at 1 μM, respectively. Mechanistically, TBBPA and TBBPS significantly inhibited the interaction between phosphatidylinositol 3-kinase (PI3K) and thyroid receptor (TR), while BPA and BPS favored the interaction between PI3K and estrogen receptor (ER), resulting in abnormal PI3K signaling with consequent distinct angiogenic activity. BPA- and BPS-induced pro-angiogenic effects and TBBPS showed anti-angiogenic effects due to their distinct disruption on the TR/ER-PI3K pathway. Our work provided new evidence and mechanistic insight on the angiogenic activity of bisphenols and expanded the scope of endocrine disruptors with interference in vascular homeostasis.

A Combination of Distinct Vascular Stem/Progenitor Cells for Neovascularization and Ischemic Rescue

BACKGROUND

Peripheral vascular disease remains a leading cause of vascular morbidity and mortality worldwide despite advances in medical and surgical therapy. Besides traditional approaches, which can only restore blood flow to native arteries, an alternative approach is to enhance the growth of new vessels, thereby facilitating the physiological response to ischemia.

METHODS

The ActinCreER/R26VT2/GK3 Rainbow reporter mouse was used for unbiased in vivo survey of injury-responsive vasculogenic clonal formation. Prospective isolation and transplantation were used to determine vessel-forming capacity of different populations. Single-cell RNA-sequencing was used to characterize distinct vessel-forming populations and their interactions.

RESULTS

Two populations of distinct vascular stem/progenitor cells (VSPCs) were identified from adipose-derived mesenchymal stromal cells: VSPC1 is CD45-Ter119-Tie2+PDGFRa-CD31+CD105highSca1low, which gives rise to stunted vessels (incomplete tubular structures) in a transplant setting, and VSPC2 which is CD45-Ter119-Tie2+PDGFRa+CD31-CD105lowSca1high and forms stunted vessels and fat. Interestingly, cotransplantation of VSPC1 and VSPC2 is required to form functional vessels that improve perfusion in the mouse hindlimb ischemia model. Similarly, VSPC1 and VSPC2 populations isolated from human adipose tissue could rescue the ischemic condition in mice.

CONCLUSIONS

These findings suggest that autologous cotransplantation of synergistic VSPCs from nonessential adipose tissue can promote neovascularization and represents a promising treatment for ischemic disease.

Sex-related external factors influence pulmonary vascular angiogenesis in a sex-dependent manner

Bronchopulmonary dysplasia (BPD) is a disease with a significant sexual dimorphism where males have a disadvantage compared with their female counterparts. Although mechanisms behind this sexual dimorphism are poorly understood, sex differences in angiogenesis have been identified as one possible source of the male disadvantage in BPD. Pulmonary angiogenesis was assessed in vitro using a bead sprouting assay with pooled male or female human pulmonary microvascular endothelial cells (HPMECs, 18-19 wk gestation, canalicular stage of human lung development) in standard (sex-hormone containing) and hormone-stripped medium. We identified sex-specific phenotypes in angiogenesis where male HPMECs produce fewer but longer sprouts compared with female HPMECs. The presence of sex hormones from standard culture medium modifies the male HPMEC phenotype with shorter and fewer sprouts but does not influence the female phenotype. Using a conditioned medium model, we further characterized the influence of the sex-specific secretome. Male and female HPMECs secrete factors that increase the maximum length of sprouts in female, but not male HPMECs. The presence of sex hormones abolishes this response. The male HPMEC secretome inhibits angiogenic sprouting in male HPMECs in the absence of sex hormones. Taken together, these results demonstrate that the pulmonary endothelial cell phenotypes are influenced by sex hormones and sex-specific secreted factors in a sex-dependent manner.NEW & NOTEWORTHY We identified a sex-specific phenotype wherein male HPMECs produce fewer but longer sprouts than females. Surprisingly, the presence of sex hormones only modifies the male phenotype, resulting in shorter and even fewer sprouts. Furthermore, we found the sex-specific secretome has a sex-dependent influence on angiogenesis that is also sex-hormone sensitive. These new and surprising findings point to the unappreciated role of sex and sex-related exogenous factors in early developmental angiogenesis.

Molecular effects of genistein, as a potential anticancer agent, on CXCR-4 and VEGF pathway in acute lymphoblastic leukemia

BACKGROUND

Vascular endothelial growth factor (VEGF) is one of the angiogenic mediators that can be secreted by leukemic cells and plays an important role in tumor invasion and metastasis. Another important agent contributing to the relapse of ALL is C-X-C chemokine receptor type-4 (CXCR-4), expression of this receptor in cancer cells has been related to metastasis. It has been identified that genistein-a soy-derived isoflavonoid-has anti-angiogenesis functions. We aimed to show the effects of this compound on VEGF and CXCR-4 in Acute lymphoblastic leukemia (ALL) cell models.

METHODS AND RESULTS

The cytotoxicity of Genistein was measured using the MTS colorimetric assay. After being treated with Genistein, the expression of VEGF in mRNA and protein levels was measured in MOLT-4 and Jurkat cells. We also used flow cytometry assay to determine the expression of CXCR-4 in cell surfaces. We found that Genistein decreased cell viability in two cell models while was more effective on MOLT-4 cells. After Genistein-treatment, surface expression levels of CXCR-4 were decreased, while VEGF secretion and mRNA expression levels were increased in MOLT-4 and Jurkat cells.

CONCLUSIONS

The results suggest that Genistein may not be a reliable choice for the treatment of ALL; however, this different identified pattern can be useful for the recognition of VEGF and CXCR-4 modulators and thus for planning new treatments for leukemia and other VEGF related disorders.

Endocrine system dysfunction and chronic heart failure: a clinical perspective

Chronic heart failure (CHF) leads to an excess of urgent ambulatory visits, recurrent hospital admissions, morbidity, and mortality regardless of medical and non-medical management of the disease. This excess of risk may be attributable, at least in part, to comorbid conditions influencing the development and progression of CHF. In this perspective, the authors examined and described the most common endocrine disorders observed in patients with CHF, particularly in individuals with reduced ejection fraction, aiming to qualify the risks, quantify the epidemiological burden and discuss about the potential role of endocrine treatment. Thyroid dysfunction is commonly observed in patients with CHF, and sometimes it could be the consequence of certain medications (e.g., amiodarone). Male and female hypogonadism may also coexist in this clinical context, contributing to deteriorating the prognosis of these patients. Furthermore, growth hormone deficiency may affect the development of adult myocardium and predispose to CHF. Limited recommendation suggests to screen endocrine disorders in CHF patients, but it could be interesting to evaluate possible endocrine dysfunction in this setting, especially when a high suspicion coexists. Data referring to long-term safety and effectiveness of endocrine treatments in patients with CHF are limited, and their impact on several "hard" endpoints (such as hospital admission, all-cause, and cardiovascular mortality) are still poorly understood.

Comparison of steroid hormones in three different preeclamptic models

Preeclampsia (PE) is a complication of pregnancy and is characterized by hypertension and proteinuria, threatening both the mother and the fetus. However, the etiology of PE has not yet been fully understood. Since the imbalance of steroid hormones is associated with the pathogenesis of PE, investigating steroidogenic mechanisms under various PE conditions is essential to understand the entire spectrum of pregnancy disorders. Therefore, the current study established three PE in vitro and in vivo models, and compared the levels of steroid hormones and steroidogenic enzymes within them. In cellular PE models induced by hypoxia, N‑nitro‑L‑arginine methyl ester hydrocholride (L‑NAME) and catechol‑o‑methyltransferase inhibitor, the levels of steroid hormones, including pregnenolone (P5), progesterone (P4), dehydroepiandrosterone (DHEA) and testosterone tended to decrease during steroidogenesis. Injection of L‑NAME in pregnant rats led to a reduction in the levels of estradiol and P4 through regulation of cholesterol side‑chain cleavage enzyme (CYP11A1) and 3β‑hydroxysteroid dehydrogenase/δ5 4‑isomerase type 1 (HSD3B1), whereas rats treated with COMT‑I exhibited elevated levels of P5 and DHEA by regulation of the CYP11A1 and aromatase cytochrome P450 (CYP19A1) in the placenta and plasma. The reduced uterine perfusion pressure operation decreased CYP11A1 and increased CYP19A1 expression in placental tissues, whereas steroid hormone levels were not altered. In conclusion, the results of the present study suggest that the induction of PE conditions dysregulates the steroid hormones via regulation of steroidogenic enzymes, depending on specific PE symptoms. These findings can contribute to the development of novel diagnostic and therapeutic modalities for PE, by monitoring and supplying appropriate levels of steroid hormones.

Multicenter phase II study of apatinib single or combination therapy in HER2-negative breast cancer involving chest wall metastasis

Objective

Breast cancer (BC) with chest wall metastasis (CWM) usually shows rich neovascularization. This trial explored the clinical effect of apatinib on human epidermal growth factor receptor 2 (HER2)-negative advanced BC involving CWM.

Methods

This trial involved four centers in China and was conducted from September 2016 to March 2020. Patients received apatinib 500 mg/d [either alone or with endocrine therapy if hormone receptor-positive (HR+)] until disease progression or unacceptable toxicity. Progression-free survival (PFS) was the primary endpoint.

Results

We evaluated 26 patients for efficacy. The median PFS (mPFS) and median overall survival (mOS) were 4.9 [range: 2.0−28.5; 95% confidence interval (95% CI): 2.1−8.3] months and 18 (range: 3−55; 95% CI: 12.9−23.1) months, respectively. The objective response rate (ORR) was 42.3% (11/26), and the disease-control rate was 76.9% (20/26). In the subgroup analysis, HR+ patients compared with HR-negative patients had significantly improved mPFS of 7.0 (95% CI: 2.2−11.8) monthsvs. 2.3 (95% CI: 1.2−3.4) months, respectively (P=0.001); and mPFS in patients without or with chest wall radiotherapy was 6.4 (95% CI: 1.6−19.5) monthsvs. 3.0 (95% CI: 1.3−4.6) months, respectively (P=0.041). In the multivariate analysis, HR+ status was the only independent predictive factor for favorable PFS (P=0.014).

Conclusions

Apatinib was highly effective for BC patients with CWM, especially when combined with endocrine therapy. PFS improved significantly in patients with HR+ status who did not receive chest wall radiotherapy. However, adverse events were serious and should be carefully monitored from the beginning of apatinib treatment.

Significance of Targeting VEGFR-2 and Cyclin D1 in Luminal-A Breast Cancer

The hormonal luminal-A is the most pre-dominant sub type of breast cancer (BC), and it is associated with a high level of cyclin D1 in Saudi patients. Tamoxifen is the golden therapy for hormonal BC, but resistance of cancer cells to tamoxifen contributes to the recurrence of BC due to many reasons, including high levels of AIB1 and cyclin D1. Overcoming drug resistance could be achieved by exploring alternative targetable therapeutic pathways and new drugs or combinations. The objective of this study was to determine the differentially enriched pathways in 12 samples of Saudi women diagnosed with luminal-A using the PamChip peptide microarray-based kinase activity profiling, and to compare the activity of HAA₂₀₂₀ and dinaciclib with tamoxifen in singles and combinations in the MCF7 luminal-A cell line. Our results of network and pathway analysis of the 12 samples highlighted the importance of VEGFR and CDKs in promoting luminal-A breast cancer. The activation of VEGF signaling via VEGFR-2 leads to activation of PI3K/AKT kinases and an increase of cell survival, and leads to activation of Hsp90, which induces the phosphorylation of FAK1, resulting in cytoskeleton remodeling. PLC-gamma 1 is also activated, leading to FAK-2 and PKC activation. Notably, the G₁/S cell cycle phases and phosphorylation processes contribute to the top seven tumorigenesis processes in the 12 samples. Further, the MTT combination of HAA₂₀₂₀ and dinaciclib showed the best combination index (CI), was more clonogenic against MCF7 cells compared to the other combinations, and it also showed the best selectivity index (SI) in normal MRC5 cells. Interestingly, HAA₂₀₂₀ and dinaciclib showed a synergistic apoptotic and G₁ cell cycle effect in MCF7 cells, which was supported by their synergistic CDK2, cyclin D1, and PCNA inhibition activities. Additionally, the combination showed VEGFR-2 and Hsp90 inhibition activities in MCF7 cells. The results show the significance of targeting VEGFR-2 and cyclin D1 in Saudi luminal-A breast cancer patients, and the effect of combining HAA₂₀₂₀ and dinaciclib on those targets in the MCF7 model. It also warrants further preclinical and in vivo investigations for the combination of HAA₂₀₂₀ and dinaciclib as a possible future second-line treatment for luminal-A breast cancers.

Angiogenesis Changes in Ovariectomized Rats with Osteoporosis Treated with Estrogen Replacement Therapy

To investigate whether angiogenesis changes in early menopausal osteoporosis treated with estrogen replacement therapy, 120 rats were randomly divided into five groups: sham operation group (SHAM), ovariectomy group (OVX), and ovariectomy plus three different estrogen doses replacement therapy groups (OVX + E2). We detected the bone microarchitecture and measured the expression levels of estrogen receptor beta (ERβ), vascular endothelial growth factor (VEGF), osteoprotegerin (OPG), and receptor activator of NF-κB ligand (RANKL). CD31 immunofluorescence and silica gel perfusion imaging were used to analyze the vascular distribution. We confirmed that the femur BMD of ovariectomized rats was significantly lower than SHAM group and OVX+E2 groups. After estrogen therapy, the local microvascular formation increased after estrogen treatment in a dose dependent manner. ERβ was downregulated and VEGF was upregulated, positively correlated with estrogen dosage. We successfully constructed an osteoporosis model of ovariectomized rats with estrogen replacement therapy. We also found angiogenesis changed in early menopausal osteoporosis treated with estrogen replacement therapy. We indicated that estrogen replacement therapy increased angiogenesis through VEGF upregulation. However, we observed that, at the highest doses of estrogen studied, increased angiogenesis was associated with a decrease in BMD, the underlying mechanisms of which remain unclear.

Estrogen Contributions to Microvascular Dysfunction Evolving to Heart Failure With Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is a syndrome involving microvascular dysfunction. No treatment is available yet and as the HFpEF patient group is expanding due to the aging population, more knowledge on dysfunction of the cardiac microvasculature is required. Endothelial dysfunction, impaired angiogenesis, (perivascular) fibrosis and the pruning of capillaries (rarefaction) may all contribute to microvascular dysfunction in the heart and other organs, e.g., the kidneys. The HFpEF patient group consists mainly of post-menopausal women and female sex itself is a risk factor for this syndrome. This may point toward a role of estrogen depletion after menopause in the development of HFpEF. Estrogens favor the ratio of vasodilating over vasoconstricting factors, which results in an overall lower blood pressure in women than in men. Furthermore, estrogens improve angiogenic capacity and attenuate (perivascular) fibrosis formation. Therefore, we hypothesize that the drop of estrogen levels after menopause contributes to myocardial microvascular dysfunction and renders post-menopausal women more vulnerable for heart diseases that involve the microvasculature. This review provides a detailed summary of molecular targets of estrogen, which might guide future research and treatment options.

Collagen type IV remodelling gender-specifically predicts mortality in decompensated cirrhosis

BACKGROUND & AIMS

Remodelling of extracellular matrix is crucial in progressive liver fibrosis. Collagen type III desposition has been shown in acute decompensation. Extratracellular matrix is compiled of deposition of various components. The role of basement membrane collagen type IV in advanced cirrhosis and acute decompensation is unclear and investigated in this study.

METHODS

Patients with decompensated cirrhosis from the prospective NEPTUN cohort (ClinicalTrials.gov Identifier: NCT03628807), who underwent transjugular intrahepatic portosystemic shunt procedure were included. Clinical and laboratory parameters, PRO-C4 and C4M levels were measured in blood samples from portal and hepatic veins just before transjugular intrahepatic portosystemic shunt placement.

RESULTS

Levels of C4M and PRO-C4 are significantly lower in patients with massive ascites and impaired renal sodium excretion. C4M and PRO-C4 show gender-specific profiles with significantly lower levels in females compared to males. Females with higher C4M levels show higher mortality. By contrast, males with higher C4M levels show lower mortality. In multivariate Cox regression analysis, C4M is an independent predictor of survival in female patients.

CONCLUSION

This study shows that markers of collagen type IV remodelling do not accumulate in severe renal dysfunction. Although collagen type IV degradation markers derive from the liver, portal venous C4M levels are relevant for survival. Moreover, it demonstrates that circulating C4M shows gender-specific profiles, which can independently predict survival in female patients with decompensated cirrhosis.

Estrogen rescues heart failure through estrogen receptor Beta activation

Background

Recently, we showed that exogenous treatment with estrogen (E2) rescues pre-existing advanced heart failure (HF) in mice. Since most of the biological actions of E2 are mediated through the classical estrogen receptors alpha (ERα) and/or beta (ERβ), and both these receptors are present in the heart, we examined the role of ERα and ERβ in the rescue action of E2 against HF.

Methods

Severe HF was induced in male mice by transverse aortic constriction-induced pressure overload. Once the ejection fraction (EF) reached ~ 35%, mice were treated with selective agonists for ERα (PPT, 850 μg/kg/day), ERβ (DPN, 850 μg/kg/day), or E2 (30 μg/kg/day) together with an ERβ-antagonist (PHTPP, 850 μg/kg/day) for 10 days.

Results

EF of HF mice was significantly improved to 45.3 ± 2.1% with diarylpropionitrile (DPN) treatment, but not with PPT (31.1 ± 2.3%). E2 failed to rescue HF in the presence of PHTPP, as there was no significant improvement in the EF at the end of the 10-day treatment (32.5 ± 5.2%). The improvement of heart function in HF mice treated with ERβ agonist DPN was also associated with reduced cardiac fibrosis and increased cardiac angiogenesis, while the ERα agonist PPT had no significant effect on either cardiac fibrosis or angiogenesis. Furthermore, DPN improved hemodynamic parameters in HF mice, whereas PPT had no significant effect.

Conclusions

E2 treatment rescues pre-existing severe HF mainly through ERβ. Rescue of HF by ERβ activation is also associated with stimulation of cardiac angiogenesis, suppression of fibrosis, and restoration of hemodynamic parameters.

Neuroprotective Effects of Guanosine Administration on In Vivo Cortical Focal Ischemia in Female and Male Wistar Rats

Guanosine (GUO) has neuroprotective effects in experimental models of brain diseases involving glutamatergic excitotoxicity in male animals; however, its effects in female animals are poorly understood. Thus, we investigated the influence of gender and GUO treatment in adult male and female Wistar rats submitted to focal permanent cerebral ischemia in the motor cortex brain. Female rats were subdivided into non-estrogenic and estrogenic phase groups by estrous cycle verification. Immediately after surgeries, the ischemic animals were treated with GUO or a saline solution. Open field and elevated plus maze tasks were conducted with ischemic and naïve animals. Cylinder task, immunohistochemistry and infarct volume analyses were conducted only with ischemic animals. Female GUO groups achieved a full recovery of the forelimb symmetry at 28-35 days after the insult, while male GUO groups only partially recovered at 42 days, in the final evaluation. The ischemic insult affected long-term memory habituation to novelty only in female groups. Anxiety-like behavior, astrocyte morphology and infarct volume were not affected. Regardless the estrous cycle, the ischemic injury affected differently female and male animals. Thus, this study points that GUO is a potential neuroprotective compound in experimental stroke and that more studies, considering the estrous cycle, with both genders are recommended in future investigation concerning brain diseases.

Estrogen receptor β-dependent Notch1 activation protects vascular endothelium against tumor necrosis factor α (TNFα)-induced apoptosis

Unlike age-matched men, premenopausal women benefit from cardiovascular protection. Estrogens protect against apoptosis of endothelial cells (ECs), one of the hallmarks of endothelial dysfunction leading to cardiovascular disorders, but the underlying molecular mechanisms remain poorly understood. The inflammatory cytokine TNFα causes EC apoptosis while dysregulating the Notch pathway, a major contributor to EC survival. We have previously reported that 17β-estradiol (E2) treatment activates Notch signaling in ECs. Here, we sought to assess whether in TNFα-induced inflammation Notch is involved in E2-mediated protection of the endothelium. We treated human umbilical vein endothelial cells (HUVECs) with E2, TNFα, or both and found that E2 counteracts TNFα-induced apoptosis. When Notch1 was inhibited, this E2-mediated protection was not observed, whereas ectopic overexpression of Notch1 diminished TNFα-induced apoptosis. Moreover, TNFα reduced the levels of active Notch1 protein, which were partially restored by E2 treatment. Moreover, siRNA-mediated knockdown of estrogen receptor β (ERβ), but not ERα, abolished the effect of E2 on apoptosis. Additionally, the E2-mediated regulation of the levels of active Notch1 was abrogated after silencing ERβ. In summary, our results indicate that E2 requires active Notch1 through a mechanism involving ERβ to protect the endothelium in TNFα-induced inflammation. These findings could be relevant for assessing the efficacy and applicability of menopausal hormone treatment, because they may indicate that in women with impaired Notch signaling, hormone therapy might not effectively protect the endothelium.

DNA methylation at birth within the promoter of ANRIL predicts markers of cardiovascular risk at 9 years

Aims

Antisense non-coding RNA in the INK4 locus (ANRIL) fixed genetic variants have consistently been linked with coronary heart disease (CHD) risk. We investigated relationships between perinatal ANRIL promoter DNA methylation and CHD risk markers in children aged 9 years. Genetic variants in the non-coding RNA ANRIL identify it as an important CHD risk locus. Increasing evidence suggests that the early life environment may act through epigenetic processes to influence later CHD risk markers such as increased arterial pulse wave velocity (PWV, a measure of arterial stiffness) blood pressure or heart rate.

Methods and results

Using pyrosequencing, ANRIL DNA methylation at nine CpG sites was measured in the umbilical cord from 144 children in a UK mother-offspring cohort and related to the descending aorta PWV measured by velocity-encoded phase contrast MRI at age 9 years. Perinatal methylation was not associated with child’s later blood pressure, but higher methylation at CpG5 was associated with increased childhood PWV (β = 0.066 m/s/10 % methylation increase [95 % CI, 0.004 to 0.128], p = 0.037); 10 % decreases in methylation at CpG1 and CpG2 were associated with increased heart rate (CpG1 β = 1.93 [0.07 to 3.8] beats/min, p = 0.041; CpG2 β = 2.30 [0.18 to 4.41] beats/min, p = 0.033, accounting for potential confounding variables). The associations with perinatal ANRIL promoter methylation were independent of neighbouring fixed genetic variants.

Conclusions

Our findings suggest developmental epigenetic regulation of ANRIL promoter methylation as a factor in later CHD risk in children.

Electronic supplementary material

The online version of this article (doi:10.1186/s13148-016-0259-5) contains supplementary material, which is available to authorized users.

Network-Based Identification and Prioritization of Key Regulators of Coronary Artery Disease Loci

OBJECTIVE

Recent genome-wide association studies of coronary artery disease (CAD) have revealed 58 genome-wide significant and 148 suggestive genetic loci. However, the molecular mechanisms through which they contribute to CAD and the clinical implications of these findings remain largely unknown. We aim to retrieve gene subnetworks of the 206 CAD loci and identify and prioritize candidate regulators to better understand the biological mechanisms underlying the genetic associations.

APPROACH AND RESULTS

We devised a new integrative genomics approach that incorporated (1) candidate genes from the top CAD loci, (2) the complete genetic association results from the 1000 genomes-based CAD genome-wide association studies from the Coronary Artery Disease Genome Wide Replication and Meta-Analysis Plus the Coronary Artery Disease consortium, (3) tissue-specific gene regulatory networks that depict the potential relationship and interactions between genes, and (4) tissue-specific gene expression patterns between CAD patients and controls. The networks and top-ranked regulators according to these data-driven criteria were further queried against literature, experimental evidence, and drug information to evaluate their disease relevance and potential as drug targets. Our analysis uncovered several potential novel regulators of CAD such as LUM and STAT3, which possess properties suitable as drug targets. We also revealed molecular relations and potential mechanisms through which the top CAD loci operate. Furthermore, we found that multiple CAD-relevant biological processes such as extracellular matrix, inflammatory and immune pathways, complement and coagulation cascades, and lipid metabolism interact in the CAD networks.

CONCLUSIONS

Our data-driven integrative genomics framework unraveled tissue-specific relations among the candidate genes of the CAD genome-wide association studies loci and prioritized novel network regulatory genes orchestrating biological processes relevant to CAD.

Estrogen Plus Progestin and Lung Cancer: Follow-up of the Women's Health Initiative Randomized Trial

INTRODUCTION

In the Women's Health Initiative (WHI) estrogen plus progestin trial, after 5.6 years' intervention and 8 years' median follow-up, more women died from lung cancer in the hormone therapy group (hazard ratio [HR], 1.71; 95% confidence interval [CI], 1.16-2.52; P = .01). Now after 14 years' median follow-up, we reexamined combined hormone therapy effects on lung cancer mortality.

PATIENTS AND METHODS

In the WHI placebo-controlled trial, 16,608 postmenopausal women aged 50 to 79 years and with an intact uterus were randomly assigned to once-daily 0.625 mg conjugated equine estrogen plus 2.5 mg medroxyprogesterone acetate (n = 8506) or placebo (n = 8102). Incidence and mortality rates for lung cancer were assessed from multivariant proportional hazard models.

RESULTS

After 14 years' cumulative follow-up, there were 219 lung cancers (0.19% per year) in the estrogen plus progestin group and 184 (0.17%) in the placebo group (HR, 1.12; 95% CI, 0.92-1.37; P = .24). While there were more deaths from lung cancer with combined hormone therapy (153 [0.13%] vs. 132 [0.12%], respectively), the difference was not statistically significant (HR, 1.09; 95% CI, 0.87-1.38; P = .45). The statistically significant increase in deaths from lung cancer observed during intervention in women assigned to estrogen plus progestin was attenuated after discontinuation of study pills (linear trend over time, P = .042).

CONCLUSION

The increased risk of death from lung cancer observed during estrogen plus progestin use was attenuated after discontinuation of combined hormone therapy.

The Role of Estrogen and Estrogen Receptors on Cardiomyocytes: An Overview

Sex differences in the onset and manifestation of cardiovascular diseases are well known, yet the mechanism behind this discrepancy remains obscure. Estrogen and its corresponding receptors have been studied for their positive salutary effects in women for decades. Estrogen protects the heart from various forms of stress, including cytotoxic, ischemic, and hypertrophic stimuli. The postulated underlying mechanism is complex, and involves the actions of the hormone on the endothelium and myocardium. Although the effects of estrogen on the coronary endothelium are well-described, delineation of the hormone's action on cardiomyocytes is still evolving. The focus of this article is to review the accumulated literature and latest data on the role of estrogen and its receptors on cardiomyocytes, the contractile cellular units of the myocardium.

Risk Factor Analysis for the Recurrence of Chronic Subdural Hematoma: A Review of 368 Consecutive Surgical Cases

OBJECTIVE

Chronic subdural hematoma (CSDH) is a common form of extra axial hemorrhage in the elderly. A surgical procedures such as a burr hole trephination are used for the CSDH treatment. The recurrence rate of CSDH is reported to range from 2.3 to 33%. In the current study, we focused on the determination of risk factors associated with the recurrence of CSDH.

METHODS

We retrospectively reviewed 368 consecutive patients with CSDH treated by burr hole trephination. Univariate and multivariate analysis were performed to describe the relationships between clinical and radiological factors as well as the recurrence of CSDH.

RESULTS

Totally 31 (8.4%) patients experienced a recurrence of CSDH in our study. The male group (10.2%) had a higher recurrence rate than the female group (3.1%). Also patients with malignant neoplasm history showed a high recurrence rate (17.9%). The recurrence rate of single layer CSDH (13.1%) and isodensity CSDH (11.7%) was highly significant also.

CONCLUSION

Sex, history of malignant neoplasm and the hematoma type on computed tomography were factors related with the recurrence of CSDH in our study. These findings may be supportive in the identification of patients at risk for a recurrence of CSDH.

Estrogen accelerates the resolution of inflammation in macrophagic cells

Although 17β-estradiol (E₂) anti-inflammatory activity has been well described, very little is known about the effects of this hormone on the resolution phase of the inflammatory process. Here, we identified a previously unreported ERα-mediated effect of E₂ on the inflammatory machinery. The study showed that the activation of the intracellular estrogen receptor shortens the LPS-induced pro-inflammatory phase and, by influencing the intrinsic and extrinsic programs, triggers the resolution of inflammation in RAW 264.7 cells. Through the regulation of the SOCS3 and STAT3 signaling pathways, E₂ facilitates the progression of the inflammatory process toward the IL10-dependent “acquired deactivation” phenotype, which is responsible for tissue remodeling and the restoration of homeostatic conditions. The present study may provide an explanation for increased susceptibility to chronic inflammatory diseases in women after menopause, and it suggests novel anti-inflammatory treatments for such disorders.

Hormonal regulation of hematopoietic stem cells and their niche: a focus on estrogen

Self-renewal and differentiation are hallmarks of stem cells and controlled by various intrinsic and extrinsic factors. Increasing evidence indicates that estrogen (E2), the primary female sex hormone, is involved in regulating the proliferation and lineage commitment of adult and pluripotent stem cells as well as modulating the stem cell niche. Thus, a detailed understanding of the role of E2 in behavior of stem cells may help to improve their therapeutic potential. Recently, it has been reported that E2 promotes cell cycle activity of hematopoietic stem and progenitor cells and induces them to megakaryocyte-erythroid progenitors during pregnancy. This study paves the way towards a previously unexplored endocrine mechanism that controls stem cell behavior. In this review, we will focus on the scientific findings regarding the regulatory effects of E2 on the hematopoietic system including its microenvironment.

Lipopolysaccharide Effect on Vascular Endothelial Factor and Matrix Metalloproteinases in Leukemic Cell Lines In vitro

Background:

Angiogenesis, the process of new vessels generation, plays a critical role in tumor invasion and metastasis. Vascular Endothelial Growth Factor (VEGF), as a cytokine, and Matrix Metalloproteinases (MMPs), has been the important factors that involved in angiogenesis. Lipopolysaccharide (LPS) has an essential effect on angiogenesis.

Objectives:

In this study the effect of LPS on VEGF production and MMP-2/MMP-9 activity in two leukemic cell lines has been assessed in vitro.

Materials and Methods:

Human leukemic U937 and THP1 cells were cultured in complete RPMI medium. Then the cells at the exponential growth phase were incubated with different concentrations of LPS (0 - 4 μg/mL) for 48 hours. Then the level of VEGF production and MMP-2/MMP-9 activity in cell culture supernatants were evaluated with the ELISA standard kits and gelatin zymography respectively.

Results:

U937 cells have produced a large amount of VEGF without any stimulus and LPS has not shown any substantial effect on VEGF production by these cells. However THP1 cells have produced a small amount of VEGF without stimulation and LPS significantly has increased VEGF production in these cells dose-dependently. Moreover LPS significantly has augmented the MMP-2/MMP-9 activity in the both leukemic cell lines in a dose-dependent manner.

Conclusions:

Our results have shown that LPS might be a potential inducer/enhancer of VEGF production and MMP-2/MMP-9 activity (angiogenic factors) in leukemia. Moreover the LPS effect on angiogenesis might be in part, due to its stimulatory effects on VEGF and MMPs. Overall LPS-stimulated leukemic cells might be good models for study and planning the useful therapeutic approaches for angiogenesis- dependent diseases.

Effect of sex and age interactions on functional outcome after stroke

Stroke is one of the leading causes of death and disability worldwide. Experimental and clinical studies showed that sex and age play an important role in deciding the outcome after stroke. At younger ages, males were shown to have a higher risk for stroke than females. However, this trend reverses in older ages particularly when females reach menopause. Many preclinical studies indicate that steroid hormones modulate the age-dependent differential stroke outcome. In addition, patterns of cell death pathways activated following cerebral ischemia are distinct between males and females, but independent of steroid hormones. Recent studies also indicate that microRNAs play important roles in mediating sex-specific stroke outcome by regulating stroke-related genes. This review discusses the contribution of sex and age to outcome after stroke with particular emphasis on the experimental studies that examined the effects of steroid hormones, differential cell death pathways, and involvement of sex-specific microRNAs following cerebral ischemia. Current understanding of the role of thrombolytic agents in stroke therapy is also discussed.

Likelihood and predictors of ST-elevation in patients hospitalized for myocardial infarction

Importance

Emergency treatment options in myocardial infarction are guided by presence or absence of ST-elevations in electrocardiography. Occurrence and factors associated with ST-presentation in different population groups are however inadequately known.

Objective

To determine likelihood and patient features associated with ST-elevations in myocardial infarction.

Design

Nationwide registry study including 22 hospitals with angiolaboratory during an eight year period in Finland.

Setting

Hospitalized care.

Participants

68,162 consecutive patients aged ≥30 with myocardial infarction.

Measures

Likelihood and patient features associated with presence of ST-elevations.

Results

Myocardial infarction presented with ST-elevation in 37.5% (CI 37.0–37.9%) and without in 62.5% (CI 61.9–63.1%) of patients, p<0.0001. Majority of patients aged 30–59 years with myocardial infarction had ST-elevation, but among octogenarians ST-elevations were present in only 24.7%. Presence of ST-elevations decreased with age by estimated 15.6% (CI 15.0–16.2%) per 10 year increase (p<0.0001). Men aged 40–79 years had significantly higher rate for ST-elevation myocardial infarction compared to women. Sex-based difference in presentation of myocardial infarction declined with increasing age. Overall, men had a 13% (CI 11–15%, p<0.0001) higher relative risk for ST-elevations compared to women when adjusted for age and co-morbidities. Diabetes, atrial fibrillation, peripheral or cerebral artery disease, chronic pulmonary disease, malignancy, and renal insufficiency were associated with absence of ST-elevations in myocardial infarction in multivariate analysis.

Conclusions and Relevance

Myocardial infarction presents with ST-elevations more commonly in men. Presence of ST-elevations decreases with increasing age. Diabetes, atrial fibrillation, peripheral or cerebral artery disease, chronic pulmonary disease, malignancy, and renal insufficiency are associated with absence of ST-elevations in myocardial infarction. These findings may help to predict likelihood of ST-elevations in a patient with myocardial infarction.

Association of the histone-lysine N-methyltransferase MLL5 gene with coronary artery disease in Chinese Han people

BACKGROUND

MLL5, a member of the histone-lysine N-methyltransferase family, has been implicated in the control of the cell cycle progression and survival. The aim of this study was to explore the relationship between the interaction of histone-lysine N-methyltransferase MLL5 gene polymorphism and CAD in a Chinese Han population.

METHODS

Using a case-control study of Chinese CAD patients (n = 565) and healthy controls (n = 694), we investigated the MLL5 gene polymorphism by the use of polymerase chain reaction fragment length polymorphism (PCR-RFLP) analysis.

RESULTS

For total, the distribution of SNP1 (rs12671368) and SNP2 (rs2192932) genotypes showed a significant difference between CAD and control participants (P1 = 0.03, P2 = 0.02). For total the distribution of SNP1 (rs12671368) and SNP2 (rs2192932) alleles in the dominant model (GG vs. AA + AG) and the recessive model (AA vs. AG + GG) showed a significant difference between CAD and control participants (for allele: P1 < 0.01 and P2 = 0.05, for dominant model: P1 > 0.05 and P2 = 0.02, for recessive model: P1 = 0.03 and P2 = 0.78, respectively). For total the significant difference of the distribution of SNP1 and SNP2 in the dominant model and recessive model was retained after adjusting for covariates (for dominant model: SNP1 OR: 1.68, 95% confidence interval [CI]: 1.08-2.64, P = 0.02; SNP2 OR: 0.51, 95% CI: 0.36-0.72, P = 0.01; for recessive model: SNP1 OR: 1.84, 95% confidence interval [CI]: 1.28-2.64, P < 0.01; SNP2 OR: 0.65, 95% CI: 0.35-1.22, P = 0.18).

CONCLUSIONS

The GG genotype of rs12671368 and the AA genotype of rs2192932 in the MLL5 gene could be protective genetic markers of CAD.

Telomeres and Estrogens: The Unholy Nexus in Pathogenesis of Atherosclerosis

Atherosclerosis (AS) is a complex inflammatory process and is categorized as a multifactorial disease involving the interplay of genetic and environmental factors. There are many factors which play role in predisposition and development of AS. In this review we have tried to address the basic pathophysiology of AS lesions and the role played by two important factors - telomeres and estrogens in the development of this disease.