Endothelin-1 and antiangiogenesis

The mechanism and treatment of targeted anti-tumour drugs induced cardiotoxicity

As the intensive anti-tumour therapy and combination of multiple anti-tumour drugs, cardiotoxicity events caused by anti-tumour drugs have also increased significantly, and the incidence of cardiotoxicity also increased with survival time. Different types of anti-tumour drugs could cause all kinds of cardiotoxicity which increase the difficulties in treatment and even live threatening. In this review, we concentrated in the targeted anti-tumour drugs such as human epidermal growth factor receptor-2 (HER2) inhibitors, tyrosine kinase inhibitors (TKIs), immune checkpoint inhibitors (ICIs), and proteasome inhibitors (Pls). The molecular mechanism of how these drugs induce cardiotoxicity is introduced which includes several signal pathways. These drugs induced cardiotoxicity involved heart failure, hypertension, atherosis and thrombosis, QT interval prolongation, and myocarditis. Some of the cardiotoxicity could be moderate and reversible but others could have happened severely.The aim of this review is to summarise the targeted anti-tumour drugs induced cardiotoxicity and treatment strategies.

The Potential for Placental Activation of PPARγ to Improve the Angiogenic Profile in Preeclampsia

Preeclampsia (PE) is one of the most common causes of maternal-fetal morbidity and mortality world-wide. While the underlying causes of PE remain elusive, aberrant trophoblast differentiation and function are thought to cause an imbalance of secreted angiogenic proteins resulting in systemic endothelial dysfunction and organ damage in the mother. The placental dysfunction is also characterized by a reduction of the transcription factor, peroxisome proliferator activated receptor γ (PPARγ) which normally promotes trophoblast differentiation and healthy placental function. This study aimed to understand how placental activation of PPARγ effects the secretion of angiogenic proteins and subsequently endothelial function. To study this, healthy and PE placental tissues were cultured with or without the PPARγ agonist, Rosiglitazone, and a Luminex assay was performed to measure secreted proteins from the placenta. To assess the angiogenic effects of placental activation of PPARγ, human umbilical vein endothelial cells (HUVECs) were cultured with the placental conditioned media and the net angiogenic potential of these cells was measured by a tube formation assay. This is the first study to show PPARγ's beneficial effect on the angiogenic profile in the human preeclamptic placenta through the reduction of anti-angiogenic angiopoietin-2 and soluble endoglin and the upregulation of pro-angiogenic placental growth factor, fibroblast growth factor-2, heparin-binding epidermal growth factor, and follistatin. The changes in the angiogenic profile were supported by the increased angiogenic potential observed in the HUVECs when cultured with conditioned media from rosiglitazone-treated preeclamptic placentas. The restoration of these disrupted pathways by activation of PPARγ in the preeclamptic placenta offers potential to improve placental and endothelial function in PE.

Emerging pharmacologic interventions for pre-eclampsia treatment

INTRODUCTION

Pre-eclampsia is a serious pregnancy complication and a major global concern for the mortality of both mother and fetus. Existing symptomatic treatments do not delay disease progression; thus, timely delivery of the baby is the most effective measure. However, the risk of various maternal and fetal injuries remains.

AREAS COVERED

In this review, we summarize the potential strategies for pharmacologic interventions in pre-eclamptic therapy. Specifically, we discuss the pathophysiological process of various effective candidate therapeutics that act on potential pathways and molecular targets to inhibit key stages of the disease. We refer to this pathogenesis-focused drug discovery model as a pathogenesis-target-drug (P-T-D) strategy. Finally, we discuss the introduction of nanotechnologies to improve the safety and efficacy of therapeutics via their specific placental targeting ability and placental retention effects.

EXPERT OPINION

Despite the active development of novel pharmacological treatments based on our current knowledge of pre-eclamptic pathogenesis, investigations are still in the early phase. Thus, further exploration of the pathological mechanisms, integrated with the P-T-D strategy and novel nanosystems, could encourage the development of more effective and safer strategies. Such advances could lead to a shift from expectant management to mechanistic-based therapy for pre-eclampsia.

Effect of High Testosterone Levels on Endothelial Function in Aorta and Erectile Function in Rats

BACKGROUND

Testosterone is an important hormone for the physical and mental health of men; however testosterone administration has also been suggested to adversely affect the cardiovascular system.

AIM

To investigate the effects of excessive testosterone administration on vascular endothelial and erectile function in rats.

METHODS

A total of seventy-five 12-week-old rats were divided into the following groups: Sham, castrated (Cast), castrated with subcutaneous administration of 100 mg/kg/month testosterone (Cast + T1), and castrated with subcutaneous administration of 100 mg/kg/week testosterone (Cast + T4). To observe the changes in testosterone level after the administration, rats were further divided into the following groups: control; T(6.25), wherein the rats were subcutaneously injected with 6.25 mg/kg testosterone; T(25) per week, wherein the rats were subcutaneously injected with 25 mg/kg testosterone per week; and T(100), wherein the rats were subcutaneously injected with 100 mg/kg testosterone per week. The relaxation responses of aorta were measured in these rats using standardized methods, and their erectile function was also evaluated. Statistical analysis of the obtained data was performed using two-way analysis of variance (ANOVA), Tukey-Kramer's multiple comparison test, or Student's t-test.

OUTCOMES

At the end of the study period, endothelial function was evaluated through measurement of isometric tension, while erectile function was assessed using intracavernosal pressure (ICP), mean arterial pressure (MAP), and the expression of endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), sirtuin 1 (Sirt1) and vascular endothelial growth factor A.

RESULTS

The ICP/MAP ratio in the Cast group (0.42 ± 0.04) was significantly lower than that in the Sham group (0.79 ± 0.07). The ICP/MAP ratio in the Cast + T1 group (0.73 ± 0.06) was significantly higher than that in the Cast group (P < .01) and that of the Cast + T4 (0.38 ± 0.01) group was unchanged (P > .05). The T(25) and T(100) groups exhibited significantly lower responses to ACh than the control group at 4 weeks (P < .01). Meanwhile, the ICP/MAP ratios in the T(25) group (0.44 ± 0.07) and T(100) group (0.47 ± 0.03) were significantly lower than that in the control group (0.67 ± 0.05) at stimulation frequencies of 16 Hz (P < .05). The expression of androgen receptor, Sirt1, and eNOS were significantly lower while that of iNOS was higher in the T(25) group compared with the control group (P < .05).

CLINICAL TRANSLATION

The results based on this animal model indicate that extremely high testosterone levels may affect endothelial and erectile function.

STRENGTHS AND LIMITATIONS

We found that high-dose testosterone administration decreased endothelial function in aorta and erectile function in rats. A major limitation of this study is that the blood concentration may not be representative of that in humans, and further research is needed.

CONCLUSION

The findings suggest that high doses of testosterone may cause endothelial dysfunction in the aorta and erectile dysfunction in rats and that the blood concentration should be monitored after testosterone administration. Kataoka T, Fukamoto A, Hotta Y, et al. Effect of High Testosterone Levels on Endothelial Function in Aorta and Erectile Function in Rats. Sex Med 2022;XX:XXXXXX.

The imprinted Igf2-Igf2r axis is critical for matching placental microvasculature expansion to fetal growth

In all eutherian mammals, growth of the fetus is dependent upon a functional placenta, but whether and how the latter adapts to putative fetal signals is currently unknown. Here, we demonstrate, through fetal, endothelial, hematopoietic, and trophoblast-specific genetic manipulations in the mouse, that endothelial and fetus-derived IGF2 is required for the continuous expansion of the feto-placental microvasculature in late pregnancy. The angiocrine effects of IGF2 on placental microvasculature expansion are mediated, in part, through IGF2R and angiopoietin-Tie2/TEK signaling. Additionally, IGF2 exerts IGF2R-ERK1/2-dependent pro-proliferative and angiogenic effects on primary feto-placental endothelial cells ex vivo. Endothelial and fetus-derived IGF2 also plays an important role in trophoblast morphogenesis, acting through Gcm1 and Synb. Thus, our study reveals a direct role for the imprinted Igf2-Igf2r axis on matching placental development to fetal growth and establishes the principle that hormone-like signals from the fetus play important roles in controlling placental microvasculature and trophoblast morphogenesis.

Differences in Endothelial Activation and Dysfunction Induced by Antiphospholipid Antibodies Among Groups of Patients With Thrombotic, Refractory, and Non-refractory Antiphospholipid Syndrome

Antiphospholipid syndrome (APS) is an autoimmune disorder characterized by pregnancy morbidity or thrombosis and persistent antiphospholipid antibodies (aPL) that bind to the endothelium and induce endothelial activation, which is evidenced by the expression of adhesion molecules and the production of reactive oxygen species (ROS) and subsequent endothelial dysfunction marked by a decrease in the synthesis and release of nitric oxide (NO). These endothelial alterations are the key components for the development of severe pathological processes in APS. Patients with APS can be grouped according to the presence of other autoimmune diseases (secondary APS), thrombosis alone (thrombotic APS), pregnancy morbidity (obstetric APS), and refractoriness to conventional treatment regimens (refractory APS). Typically, patients with severe and refractory obstetric APS exhibit thrombosis and are classified as those having primary or secondary APS. The elucidation of the mechanisms underlying these alterations according to the different groups of patients with APS could help establish new therapies, particularly necessary for severe and refractory cases. Therefore, this study aimed to evaluate the differences in endothelial activation and dysfunction induced by aPL between patients with refractory obstetric APS and other APS clinical manifestations. Human umbilical vein endothelial cells (HUVECs) were stimulated with polyclonal immunoglobulin-G (IgG) from different groups of patients n = 21), including those with primary (VTI) and secondary thrombotic APS (VTII) and refractory primary (RI+), refractory secondary (RII+), and non-refractory primary (NR+) obstetric APS. All of them with thrombosis. The expression of adhesion molecules; the production of ROS, NO, vascular endothelial growth factor (VEGF), and endothelin-1; and the generation of microparticles were used to evaluate endothelial activation and dysfunction. VTI IgG induced the expression of adhesion molecules and the generation of microparticles and VEGF. RI+ IgG induced the expression of adhesion molecules and decreased NO production. RII+ IgG increased the production of microparticles, ROS, and endothelin-1 and reduced NO release. NR+ IgG increased the production of microparticles and endothelin-1 and decreased the production of VEGF and NO. These findings reveal differences in endothelial activation and dysfunction among groups of patients with APS, which should be considered in future studies to evaluate new therapies, especially in refractory cases.

Epithelial-mesenchymal transition-related serum markers ET-1, IL-8 and TGF-β2 are elevated in a Finnish wet age-related macular degeneration cohort

PURPOSE

It has been hypothesized that epithelial-mesenchymal transition (EMT) may occur in the retinal pigment epithelium of advanced stage age-related macular degeneration (AMD). Various serum and plasma growth factors and inflammatory mediators have been linked to AMD. We were interested in finding out whether systemic levels of EMT-associated markers were altered in the serum of wet AMD patients. Serum biomarkers associated with the various pathological processes of AMD may present an avenue towards identifying and characterizing the birth mechanisms of wet AMD, its progression and severity, paving the way towards the application of precision medicine.

METHODS

We chose to measure the serum levels of known biomarkers of EMT - EGF (epidermal growth factor), ET-1 (endothelin 1), IL-8 (interleukin 8), TGF-β1 and TGF-β2 (transforming growth factor-beta 1 and 2) and VEGF-A (vascular endothelial growth factor A) - using enzyme-linked immunosorbent assays. We measured them from 71 Finnish wet AMD patients who were receiving intravitreal anti-VEGF-A injection treatments, as well as 64 age-adjusted controls.

RESULTS

We found significantly elevated levels of ET-1, IL-8 and TGF-β2 in the serums of wet AMD patients.

CONCLUSIONS

ET-1, IL-8 and TGF-β2 appear to be useful serum biomarkers in understanding active wet AMD. However, we cannot conclude that local retinal EMT-processes could be observed from the corresponding systemic serum biomarkers in patients undergoing anti-VEGF-A treatments.

The Protective Benefit of Heme Oxygenase-1 Gene-Modified Human Placenta-Derived Mesenchymal Stem Cells in a N-Nitro-L-Arginine Methyl Ester-Induced Preeclampsia-Like Rat Model: Possible Implications for Placental Angiogenesis

We previously reported that cytoprotective Heme oxygenase-1, HO-1 (HMOX1) gene-modified human placenta-derived mesenchymal stem cell (HO-1-PMSC) improved placental vascularization in vitro. In the current study, we explored the protective benefit of HO-1-PMSC transplantation in a preeclampsia (PE)-like rat model. A model of PE was successfully constructed by intraperitoneal injection of N-nitro-L-arginine methyl ester (L-NAME). Blood pressure and urinary protein levels were measured. Doppler ultrasound was examined to understand uteroplacental perfusion. ELISA was used to examine the serum levels of VEGF, PlGF, sFlt-1, and sEng. The placentas and fetuses were weighed to verify the improvement in pregnancy outcome. Immunohistochemical and H&E staining was used to detect microvessel density (MVD) in placental tissues and kidney pathology, respectively. The distribution of GFP-labeled PMSC in the placenta were observed under fluorescence microscopy. Blood pressure and proteinuria were reduced and kidney damage was improved. PE rat models treated with PMSC and HO-1-PMSC exhibited an increase in the quality of fetuses and placentas, MVD, VEGF, and PlGF expression, but substantially decreased expression of sFlt-1 and sEng. Doppler ultrasound showed that the placental perfusion was improved. Green fluorescent tracing experiments verified that the cells were successfully transplanted into the placenta and distributed in the blood vessels, indicating that the cells might participate in the process of angiogenesis. These results indicate that therapy with HO-1-PMSC could improve placental vascular dysplasia, increase placental perfusion, control PE symptoms, and promote pregnancy outcome by regulating the balance of angiogenic and antiangiogenic factors or directly participating in the repair of placental vessels in a PE-like rat model.

Exploring the Influence of Different Albumin Binders on Molecular Imaging Probe Distribution

The biodistribution of molecular imaging probes or tracers mainly depends on the chemical nature of the probe and the preferred metabolization and excretion routes. Small molecules have rather short half-lives while antibodies reside inside the organism for a longer period of time. An excretion via kidneys and bladder is faster than a mainly hepatobiliary elimination. To manipulate the biodistribution behavior of probes, different strategies have been pursued, including utilizing serum albumin as an inherent transport mechanism for small molecules. Here, we modified an existing small molecular fluorescent probe targeted to the endothelin-A receptor (ET_AR) with three different albumin-binding moieties to search for an optimal modification strategy. A diphenylcyclohexyl (DPCH) group, a p-iodophenyl butyric acid (IPBA), and a fatty acid (FA) group were attached via amino acid linkers. All three modifications result in transient albumin binding of the developed compounds, as concluded from gel electrophoresis investigations. Spectrophotometric measurements applying variable amounts of bovine, murine, and human serum albumin (BSA, MSA, and HSA) reveal distinct variations of absorption and emission intensities and shifts of their maximum wavelengths. Binding to MSA results in the weakest effects, while binding to HSA leads to the strongest. Cell-based in vitro investigations utilizing ET_AR-positive HT-1080 fibrosarcoma and ET_AR-negative BT-20 breast adenocarcinoma cells support a retained specific target-binding capacity of the modified compounds and different degrees of unspecific binding. In vivo analysis of a HT-1080 xenograft model in nude mice over the course of 1 week by fluorescence reflectance imaging illustrates noticeable differences between the four examined probes. While the IPBA-modified probe shows the highest absolute signal intensity values, the FA-modified probe exhibits the most favorable tumor-to-organ ratios. In summary, reversible binding to albumin enhances the biological half-life of the designed probes substantially and enables near infrared optical imaging of subcutaneous tumors for several days in vivo. Because the unmodified probe already exhibits reasonable results, the attachment of albumin-binding moieties does not lead to a substantially improved imaging outcome in terms of target-to-background ratios. On the other hand, because the implemented transient albumin binding results in an overall higher amount of probe inside tumor lesions, this strategy might be adaptable for theranostic or therapeutic approaches in a future clinical routine.

The Molecular Mechanisms of Cardiotoxicity Induced by HER2, VEGF, and Tyrosine Kinase Inhibitors: an Updated Review

AIM

In recent decades, there has been a revolutionary decrease in cancer-related mortality and an increase in survival due to the introduction of novel targeted drugs. Nevertheless, drugs targeting human epidermal growth factor receptor 2 (HER-2), angiogenesis, and other tyrosine kinases also come with unexpected cardiac side effects, including heart failure, hypertension, arterial thrombosis, and arrhythmias, and have mechanisms that are unlike those of classic chemotherapeutic agents. In addition, it is challenging to address some problems, as the existing guidelines need to be more specific, and further large-scale clinical trials and experimental studies are required to confirm the benefit of administering cardioprotective agents to patients treated with targeted therapies. Therefore, an improved understanding of cardiotoxicity becomes increasingly important to minimize the pernicious effects and maximize the beneficial effects of targeted agents.

METHODS

"Cardiotoxicity", "targeted drugs", "HER2", "trastuzumab", "angiogenesis inhibitor", "VEGF inhibitor" and "tyrosine kinase inhibitors" are used as keywords for article searches.

RESULTS

In this article, we report several targeted therapies that induce cardiotoxicity and update knowledge of the clinical evidence, molecular mechanisms, and management measures.

Nephrotoxicity of Anti-Angiogenic Therapies

The use of inhibitors of vascular endothelial growth factor (VEGF)/vascular endothelial growth factor receptor 2 (VEGFR2) signaling for the treatment of cancer has increased over the last decade. This signaling pathway plays a fundamental role in angiogenesis and also in kidney physiology. The emergence of anti-angiogenic therapies has led to adverse nephrotoxic effects, despite improving the outcomes of patients. In this review, we will present the different anti-angiogenic therapies targeting the VEGFR pathway in association with the incidence of renal manifestations during their use. In addition, we will discuss, in detail, the pathophysiological mechanisms of frequent renal diseases such as hypertension, proteinuria, renal dysfunction, and electrolyte disorders. Finally, we will outline the cellular damage described following these therapies.

Impaired endothelial function irrespective of systemic inflammation or atherosclerosis in mastocytosis

BACKGROUND

Knowledge on endothelial dysfunction and its relation to atherosclerosis in mastocytosis is limited.

OBJECTIVE

To investigate the endothelial function in mastocytosis by flow-mediated dilatation (FMD) and biomarkers related to vascular endothelia and to evaluate its relationship with the presence of subclinical atherosclerosis by carotid intima media thickness (CIMT).

METHODS

A total of 49 patients with mastocytosis and 25 healthy controls (HCs) were included. The FMD and CIMT during transthoracic echocardiography biomarkers including endocan, endothelin-1, and vascular endothelial growth factor (VEGF) were measured in the sera of participants. Tumor necrosis factor-alpha, interleukin 6, and high-sensitive C-reactive protein were determined as inflammatory biomarkers.

RESULTS

The mean FMD % was lower in the patients than HCs (11.26% ± 5.85% vs 17.84% ± 5.27% P < .001) and was the lowest in the advanced systemic mastocytosis and smoldering systemic mastocytosis group among the patients (P = .03). The median value of VEGF was considerably higher in patients than HCs (73.30 pg/mL; minimum-maximum 32.46-295.29 pg/mL vs 46.64 pg/mL; minimum-maximum, 11.09-99.86 pg/mL; P = .001) and it was the highest in the advanced systemic mastocytosis and smoldering systemic mastocytosis group (P = .01). The FMD was inversely correlated with endocan (r = -0.390; P = .006), endothelin-1 (r = -0.363; P = .01) and VEGF (r = -0.402; P = .004) but there were no correlations between FMD and tumor necrosis factor-alpha, interleukin 6, and high-sensitive C-reactive protein. No differences in CIMT values between patients and HCs and no correlation between CIMT and the biomarkers were observed.

CONCLUSION

Endothelial dysfunction in mastocytosis becomes evident with decreased FMD and elevated serum VEGF in the absence of atherosclerosis or systemic inflammation and is related to disease severity.

Shedding light on the pathophysiology of preeclampsia-syndrome in the era of Cardio-Obstetrics: Role of inflammation and endothelial dysfunction

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Preeclampsia (PE) is a worldwide pregnancy complication with serious maternal and neonatal consequences. Our understanding of PE pathophysiology has significantly evolved over the last decades by recognizing that endothelial dysfunction and systemic inflammation, with an associated angiogenic imbalance, are key pieces of this still incomplete puzzle. In the present era, where no single treatment to cure or treat this obstetric condition has been developed so far, PE prevention and early prediction poses the most useful clinical approach to reduce the PE burden. Although most PE episodes occur in healthy nulliparous women, the identification of specific clinical conditions that increase dramatically the risk of PE provides a critical opportunity to improve outcomes by acting on potential reversible factors, and also contribute to better understand this pathophysiologic enigma. In this review, we highlight major clinical contributors of PE and shed light about their potential link with endothelial dysfunction and inflammation.

Hypertension in Cancer Patients and Survivors: Epidemiology, Diagnosis, and Management

Cancer patients and survivors of cancer have a greater burden of cardiovascular disease compared to the general population. Much of the elevated cardiovascular risk in these individuals is likely attributable to hypertension, as individuals with cancer have a particularly high incidence of hypertension following cancer diagnosis. Treatment with chemotherapy is an independent risk factor for hypertension due to direct effects of many agents on endothelial function, sympathetic activity, and renin-angiotensin system activity as well as nephrotoxicity. Diagnosis and management of hypertension in cancer patients requires accurate blood pressure measurement and consideration of potential confounding factors, such as adjuvant treatments and acute pain, that can temporarily elevate blood pressure readings. Home blood pressure monitoring can be a useful tool to facilitate longitudinal blood pressure monitoring for titration of antihypertensive medications. Selection of antihypertensive agents in cancer patients should account for treatment-specific morbidities and target organ injury.

Pre-eclampsia: pathogenesis, novel diagnostics and therapies

Pre-eclampsia is a complication of pregnancy that is associated with substantial maternal and fetal morbidity and mortality. The disease presents with new-onset hypertension and often proteinuria in the mother, which can progress to multi-organ dysfunction, including hepatic, renal and cerebral disease, if the fetus and placenta are not delivered. Maternal endothelial dysfunction due to circulating factors of fetal origin from the placenta is a hallmark of pre-eclampsia. Risk factors for the disease include maternal comorbidities, such as chronic kidney disease, hypertension and obesity; a family history of pre-eclampsia, nulliparity or multiple pregnancies; and previous pre-eclampsia or intrauterine fetal growth restriction. In the past decade, the discovery and characterization of novel antiangiogenic pathways have been particularly impactful both in increasing understanding of the disease pathophysiology and in directing predictive and therapeutic efforts. In this Review, we discuss the pathogenic role of antiangiogenic proteins released by the placenta in the development of pre-eclampsia and review novel therapeutic strategies directed at restoring the angiogenic imbalance observed during pre-eclampsia. We also highlight other notable advances in the field, including the identification of long-term maternal and fetal risks conferred by pre-eclampsia.

Preeclampsia: Maternal Systemic Vascular Disorder Caused by Generalized Endothelial Dysfunction Due to Placental Antiangiogenic Factors

Preeclampsia, a systemic vascular disorder characterized by new-onset hypertension and proteinuria after 20 weeks of gestation, is the leading cause of maternal and perinatal morbidity and mortality. Maternal endothelial dysfunction caused by placental factors has long been accepted with respect to the pathophysiology of preeclampsia. Over the past decade, increased production of placental antiangiogenic factors has been identified as a placental factor leading to maternal endothelial dysfunction and systemic vascular dysfunction. This review summarizes the recent advances in understanding the molecular mechanisms of endothelial dysfunction caused by placental antiangiogenic factors, and the novel clinical strategies based on these discoveries.

Human Skin-Derived Mast Cells Spontaneously Secrete Several Angiogenesis-Related Factors

Mast cells are classically recognized as cells that cause IgE-mediated allergic reactions. However, their ability to store and secrete vascular endothelial growth factor (VEGF) suggests a role in vascular development and tumorigenesis. The current study sought to determine if other angiogenesis-related factors, in addition to VEGF, were also secreted by human tissue-derived mast cells. Using proteome array analysis and ELISA, we found that human skin-derived mast cells spontaneously secrete CXCL16, DPPIV, Endothelin-1, GM-CSF, IL-8, MCP-1, Pentraxin 3, Serpin E1, Serpin F1, TIMP-1, Thrombospondin-1, and uPA. We identified three groups based on their dependency for stem cell factor (SCF), which is required for mast cell survival: Endothelin-1, GM-CSF, IL-8, MCP-1, and VEGF (dependent); Pentraxin 3, Serpin E1, Serpin F1, TIMP-1, and Thrombospondin-1 (partly dependent); and CXCL16, DPPIV, and uPA (independent). Crosslinking of FcεRI with multivalent antigen enhanced the secretion of GM-CSF, Serpin E1, IL-8, and VEGF, and induced Amphiregulin and MMP-8 expression. Interestingly, FcεRI signals inhibited the spontaneous secretion of CXCL16, Endothelin-1, Serpin F1, Thrombospondin-1, MCP-1 and Pentraxin-3. Furthermore, IL-6, which we previously showed could induce VEGF, significantly enhanced MCP-1 secretion. Overall, this study identified several angiogenesis-related proteins that, in addition to VEGF, are spontaneously secreted at high concentrations from human skin-derived mast cells. These findings provide further evidence supporting an intrinsic role for mast cells in blood vessel formation.

An update on the conquests and perspectives of cardio-oncology in the field of tumor angiogenesis-targeting TKI-based therapy

INTRODUCTION

The angiogenesis mechanism is considered a crucial point in neoplastic development. A growing number of multi-targeted tyrosine kinase inhibitors (TKI) has been developed and approved for cancer treatment during the last few years. Cardiac side effects still remain an issue to manage nowadays. These drugs mechanisms and toxicities have already been discussed, hence the authors will report updates on these already available drugs.

AREAS COVERED

This manuscript provides an updated review on the new mechanisms involved in angiogenesis and cardiotoxicity that are TKI-related. Here is reported an overview of the already available and the most recent TKIs under investigation in the oncology field. A literature review has been performed, focusing on the most relevant phase II and phase III trial results.

EXPERT OPINION

TKIs represent a new and important resource in the oncology field. Since the use and the number of VEGFR-TKI is constantly increasing, a specific focus on cardiotoxicity development and management appears as justified. Oncologists must record cardiovascular risk factors at baseline in order to stratify patients' risk before undergoing TKI-VEGFRs. A collaboration between oncologists and cardio-oncologists is strongly recommended to earlier manage cardiovascular events (i.e. arterial hypertension) that could interfere with oncological results.

Sustained, delayed, and small increments in glomerular permeability to macromolecules during systemic ET-1 infusion mediated via the ETA receptor

Emerging evidence indicates that endogenous production of endothelin (ET)-1, a 21-amino acid peptide vasoconstrictor, plays an important role in proteinuric kidney disease. Previous studies in rats have shown that chronic administration of ET-1 leads to increased glomerular albumin leakage. The underlying mechanisms are, however, currently not known. Here, we used size-exclusion chromatography to measure glomerular sieving coefficients for neutral FITC-Ficoll (molecular Stokes-Einstein radius: 15-80 Å, molecular weight: 70 kDa/400 kDa) in anesthetized male Sprague-Dawley rats (n = 12) at baseline and at 5, 15, 30, and 60 min after intravenous administration of ET-1. In separate experiments, ET-1 was given together with the selective ET type A (ET_A) or ET type B (ET_B) receptor antagonists JKC-301 and BQ-788, respectively. At both 15 and 30 min postadministration, the glomerular sieving coefficient for macromolecular Ficoll (70 Å) was significantly increased to 4.4 × 10^-5 ± 0.7 × 10^-5 (P = 0.024) and 4.5 × 10^-5 ± 0.8 × 10^-5 (P = 0.007), respectively, compared with baseline (2.2 × 10^-5 ± 0.4 ×10^-5). Decreased urine production after ET-1 prevented the use of higher doses of ET-1. Data analysis using the two-pore model indicated changes in large-pore permeability after ET-1, with no changes in the small-pore pathway. Administration of ET_A blocker abrogated the permeability changes induced by ET-1 at 30 min, whereas blockade of ET_B receptors was ineffective. Mean arterial pressure was only significantly increased at 60 min, being 123 ± 4 mmHg compared with 111 ± 2 mmHg at baseline (P = 0.02). We conclude that ET-1 evoked small, delayed, and sustained increases in glomerular permeability, mediated via the ET_A receptor.

Angiogenic Endothelial Cell Signaling in Cardiac Hypertrophy and Heart Failure

Endothelial cells are, by number, one of the most abundant cell types in the heart and active players in cardiac physiology and pathology. Coronary angiogenesis plays a vital role in maintaining cardiac vascularization and perfusion during physiological and pathological hypertrophy. On the other hand, a reduction in cardiac capillary density with subsequent tissue hypoxia, cell death and interstitial fibrosis contributes to the development of contractile dysfunction and heart failure, as suggested by clinical as well as experimental evidence. Although the molecular causes underlying the inadequate (with respect to the increased oxygen and energy demands of the hypertrophied cardiomyocyte) cardiac vascularization developing during pathological hypertrophy are incompletely understood. Research efforts over the past years have discovered interesting mediators and potential candidates involved in this process. In this review article, we will focus on the vascular changes occurring during cardiac hypertrophy and the transition toward heart failure both in human disease and preclinical models. We will summarize recent findings in transgenic mice and experimental models of cardiac hypertrophy on factors expressed and released from cardiomyocytes, pericytes and inflammatory cells involved in the paracrine (dys)regulation of cardiac angiogenesis. Moreover, we will discuss major signaling events of critical angiogenic ligands in endothelial cells and their possible disturbance by hypoxia or oxidative stress. In this regard, we will particularly highlight findings on negative regulators of angiogenesis, including protein tyrosine phosphatase-1B and tumor suppressor p53, and how they link signaling involved in cell growth and metabolic control to cardiac angiogenesis. Besides endothelial cell death, phenotypic conversion and acquisition of myofibroblast-like characteristics may also contribute to the development of cardiac fibrosis, the structural correlate of cardiac dysfunction. Factors secreted by (dysfunctional) endothelial cells and their effects on cardiomyocytes including hypertrophy, contractility and fibrosis, close the vicious circle of reciprocal cell-cell interactions within the heart during pathological hypertrophy remodeling.

Exosomes released from pancreatic cancer cells enhance angiogenic activities via dynamin-dependent endocytosis in endothelial cells in vitro

Pancreatic cancer has the lowest 5 year survival rate among all cancers. Several extracellular factors are involved in the development and metastasis of pancreatic cancer to distant organs. Exosomes are lipid-bilayer, membrane-enclosed nanoparticles that are recognised as important mediators of cell-to-cell communications. However, the role of exosomes released from pancreatic cancer cells in tumour micro-environment remains unknown. Here, we show that exosomes released from pancreatic cancer PK-45H cells activate various gene expressions in human umbilical vein endothelial cells (HUVECs) by in vitro analyses. In addition, these exosomes released from PK-45H cells promote phosphorylation of Akt and ERK1/2 signalling pathway molecules and tube formation via dynamin-dependent endocytosis in HUVECs. Our findings suggested that exosomes released from pancreatic cancer cells may act as a novel angiogenesis promoter.

Int6/eIF3e Silencing Promotes Placenta Angiogenesis in a Rat Model of Pre-eclampsia

We investigated whether stable eukaryotic translation initiation factor 3e/inter 6 (eIF-3e/Int6) RNA-silencing (siRNA-Int6) can ameliorate pre-eclampsia (PE) by promoting angiogenesis in an N-nitro-L-arginine methyl ester (L-NAME)-induced rat pre-eclampsia (PE) model. Twenty-four pregnant female Sprague–Dawley rats were allocated into 4 groups, including controls (Con) without any treatment, and 18 from gestational day (GD) 7 to GD17 L-NAME-treated rats, which were divided into stable siRNA-Int6 transfected (siRNA-Int6), negative vector control siRNA (NC-siRNA) and PE control (PE-Con) groups. All adenovirus siRNA transfections were performed on GD7 via intravenous tail injection. On GD0, GD11 and GD17, blood pressure, and on GD6 and GD17, protein estimations in 24 h urine samples were conducted. All animals were sacrificed on GD18. In the PE-Con group, placental Int6 was expressed to a significantly greater level than in the Con group, which was reversed by the application of siRNA-Int6. Blood pressure and proteinuria were significantly lower in the siRNA-Int6 group than in the PRE-Con group. As shown by CD31 and IB4 expression, placental micro-vascular density (MVD) was significantly higher in the siRNA-Int6 group than in the PE-Con and NC-siRNA groups, which has accompanied by enhanced trophoblast invasion. Int6 silencing alleviated the maternal clinical manifestations of pre-eclampsia and promoted placental angiogenesis in pregnant L-NAME-treated rats.

Bevacizumab Injection in Patients with Neovascular Age-Related Macular Degeneration Increases Angiogenic Biomarkers

Purpose

To evaluate the expression of 19 angiogenic biomarkers in the aqueous humor before and after intravitreal bevacizumab injection (IVB) in eyes with neovascular age-related macular degeneration (AMD).

Design

Prospective, noncomparative, interventional case series.

Participants

Twenty-three eyes of 23 treatment-naïve patients with choroidal neovascularization (CNV) secondary to neovascular AMD.

Methods

Eyes were diagnosed with CNV secondary to neovascular AMD and were treated with 3 monthly IVBs. Aqueous humor samples were obtained by anterior chamber paracentesis at baseline and immediately before each intravitreal bevacizumab injection.

Main Outcome Measures

Aqueous humor levels of 19 angiogenic biomarkers (angiopoietin 2, bone morphogenetic protein 9 [BMP-9], epidermal growth factor [EGF], endoglin, endothelin 1, fibroblast growth factor [FGF]-1 and FGF-2, follistatin, granulocyte colony-stimulating factor [GCSF], heparin-binding EGF-like growth factor [HB-EGF], hepatocyte growth factor [HGF], interleukin 8, leptin, placental growth factor [PLGF], vascular endothelial growth factor [VEGF]-A, VEGF-C, VEGF-D, and tissue inhibitor of metalloproteinases [TIMP]-1 and TIMP-2) were measured. Best-corrected visual acuity (BCVA), spectral-domain OCT parameters, and intraocular pressure also were evaluated.

Results

Baseline aqueous VEGF-A expression was elevated in all study eyes before treatment initiation. A statistically significant decrease of VEGF-A was observed at the 1- and 2-month follow-ups. A statistically significant increased concentration was observed in 7 biomarkers: VEGF-C, angiopoietin 2, endothelin 1, follistatin, HB-EGF, HGF, and interleukin 8. The other 11 study biomarker levels (VEGF-D, BMP-9, EGF, endoglin, FGF-1, FGF-2, GCSF, leptin, PLGF, TIMP-1, and TIMP-2) did not show any significant difference during follow-up. The BCVA statistically improved significantly at 2 months. Spectral-domain OCT parameters improved significantly at all follow-ups. Mean intraocular pressure values were not statistically different during the study period.

Conclusions

Despite a decrease in VEGF-A, the aqueous levels of VEGF-C, angiopoietin 2, endothelin 1, follistatin, HB-EGF, HGF, and interleukin 8 increased significantly after intravitreal injection of bevacizumab. These upregulated angiogenic biomarkers may represent new therapeutic targets in exudative AMD.

Altered Endothelial Nitric Oxide Signaling as a Paradigm for Maternal Vascular Maladaptation in Preeclampsia

PURPOSE OF REVIEW

The goal of this review is to present the newest insights into what we view as a central failure of cardiovascular adaptation in preeclampsia (PE) by focusing on one clinically significant manifestation of maternal endothelial dysfunction: nitric oxide signaling. The etiology, symptoms, and current theories of the PE syndrome are described first, followed by a review of the available evidence, and underlying causes of reduced endothelial nitric oxide (NO) signaling in PE.

RECENT FINDINGS

PE maladaptations include, but are not limited to, altered physiological stimulatory inputs (e.g., estrogen; VEGF/PlGF; shear stress) and substrates (L-Arg; ADMA), augmented placental secretion of anti-angiogenic and inflammatory factors such as sFlt-1 and Eng, changes in eNOS (polymorphisms, expression), and reduced bioavailability of NO secondary to oxidative stress. PE is a complex obstetrical syndrome that is associated with maternal vascular dysfunction. Diminished peripheral endothelial vasodilator influence in general, and of NO signaling specifically, are key in driving disease progression and severity.

Cardiovascular dysfunction in sepsis at the dawn of emerging mediators

Subcellular dysfunction and impaired metabolism derived from the complex interaction of cytokines and mediators with cellular involvement are on the basis of the cardiovascular response to sepsis. The lethal consequences of an infection are intimately related to its ability to spread to other organ sites and the immune system of the host. About one century ago, William Osler (1849-1919), a Canadian physician, remarkably defined the sequelae of the host response in sepsis: "except on few occasions, the patient appears to die from the body's response to infection rather than from it." Cardiac dysfunction has received considerable attention to explain the heart failure in patients progressing from infection to sepsis, but our understanding of the processes remains limited. In fact, most concepts are linked to a mechanical concept of the sarcomeric structure, and physiological data seems to be often disconnected. Cytokines, prostanoids, and nitric oxide release are high direct impact factors, but coronary circulation and cardiomyocyte physiology also play a prominent role in modulating the effects of monocyte adhesion and infiltration. Damage-associated molecular patterns (DAMPs) and pathogen-associated molecular patterns (PAMPs) are involved in the host response. The identification of microRNAs, as well as the cyclic activation of the inflammatory cascade, has further added complexity to the scene. In this review, we delineate the current concepts of cellular dysfunction of the cardiomyocyte in the setting of sepsis and consider potential therapeutic strategies.

Plasma endothelin-1 level as a predictor for poor collaterals in patients with ≥95% coronary chronic occlusion

BACKGROUND

Coronary collateral circulation (CCC) plays an important role in protecting myocardium from ischemic damage. The studies on factors which impact on CCC might be of great clinical interest. The aim of the present study was to evaluate endothelin-1 (ET-1) as a potential predictor for poor or good CCC in patients with angiography-proven ≥95% coronary occlusion.

METHODS

We screened 1038 consecutive patients with ≥95% occlusion in at least one major epicardial coronary artery detected by coronary angiography. Of these, 663 patients were classified into the poor CCC group with Rentrop 0-2 grade collateral circulation and 375 patients into the good CCC group with Rentrop 3 grade. The association of plasma ET-1 levels with collateral status was assessed.

RESULTS

We found that patients in the poor CCC group had a higher ET-1 level than those in the good CCC group (0.59±0.48 vs. 0.39±0.32pmol/L, p<0.001), and the ET-1 values increased with the descent of the Rentrop grades (p for trend<0.001). Moreover, multivariate logistic regression analysis revealed an independent association between ET-1 and collateral status (odds ratio [95% CI] for poor CCC 2.27 [1.60-3.22], p<0.001). Additionally, the association presented significance in both men (odds ratio [95% CI] for poor CCC 3.18 [2.20-4.74], p<0.001) and women (odds ratio [95% CI] for poor CCC 3.10 [1.36-7.85], p=0.011) when the sex-specific analysis was performed.

CONCLUSIONS

Plasma ET-1 level may be a useful, easily available marker for predicting the degree of CCC in patients with ≥95% coronary chronic occlusion.

Therapeutic potential of endothelin receptor antagonism in kidney disease

Our growing understanding of the role of the endothelin (ET) system in renal physiology and pathophysiology is from emerging studies of renal disease in animal models and humans. ET receptor antagonists reduce blood pressure and proteinuria in chronic kidney disease and cause regression of renal injury in animals. However, the therapeutic potential of ET receptor antagonism has not been fully explored and clinical studies have been largely limited to patients with diabetic nephropathy. There remains a need for more work in nondiabetic chronic kidney disease, end-stage renal disease (patients requiring maintenance dialysis and those with a functioning kidney transplant), ischemia reperfusion injury, and sickle cell disease. The current review summarizes the most recent advances in both preclinical and clinical studies of ET receptor antagonists in the field of kidney disease.

Novel Pathophysiological Mechanisms in Hypertension

Hypertension is the most common disease affecting humans and imparts a significant cardiovascular and renal risk to patients. Extensive research over the past few decades has enhanced our understanding of the underlying mechanisms in hypertension. However, in most instances, the cause of hypertension in a given patient continues to remain elusive. Nevertheless, achieving aggressive blood pressure goals significantly reduces cardiovascular morbidity and mortality, as demonstrated in the recently concluded SPRINT trial. Since a large proportion of patients still fail to achieve blood pressure goals, knowledge of novel pathophysiologic mechanisms and mechanism based treatment strategies is crucial. The following chapter will review the novel pathophysiological mechanisms in hypertension, with a focus on role of immunity, inflammation and vascular endothelial homeostasis. The therapeutic implications of these mechanisms will be discussed where applicable.

Vascular Complications of Cancer Chemotherapy

Development of new anticancer drugs has resulted in improved mortality rates and 5-year survival rates in patients with cancer. However, many of the modern chemotherapies are associated with cardiovascular toxicities that increase cardiovascular risk in cancer patients, including hypertension, thrombosis, heart failure, cardiomyopathy, and arrhythmias. These limitations restrict treatment options and might negatively affect the management of cancer. The cardiotoxic effects of older chemotherapeutic drugs such as alkylating agents, antimetabolites, and anticancer antibiotics have been known for a while. The newer agents, such as the antiangiogenic drugs that inhibit vascular endothelial growth factor signalling are also associated with cardiovascular pathology, especially hypertension, thromboembolism, myocardial infarction, and proteinuria. Exact mechanisms by which vascular endothelial growth factor inhibitors cause these complications are unclear but impaired endothelial function, vascular and renal damage, oxidative stress, and thrombosis might be important. With increasing use of modern chemotherapies and prolonged survival of cancer patients, the incidence of cardiovascular disease in this patient population will continue to increase. Accordingly, careful assessment and management of cardiovascular risk factors in cancer patients by oncologists and cardiologists working together is essential for optimal care so that prolonged cancer survival is not at the expense of increased cardiovascular events.