Microvascular Endothelial Inflammation Research Articles

Potential Mechanisms of the Protective Effects of the Cardiometabolic Drugs Type-2 Sodium-Glucose Transporter Inhibitors and Glucagon-like Peptide-1 Receptor Agonists in Heart Failure.

Different multifactorial pathophysiological processes are involved in the development of heart failure (HF), including neurohormonal dysfunction, the hypertrophy of cardiomyocytes, interstitial fibrosis, microvascular endothelial inflammation, pro-thrombotic states, oxidative stress, decreased nitric oxide (NO) bioavailability, energetic dysfunction, epicardial coronary artery lesions, coronary microvascular rarefaction and, finally, cardiac remodeling. While different pharmacological strategies have shown significant cardiovascular benefits in HF with reduced ejection fraction (HFrEF), there is a residual unmet need to fill the gap in terms of knowledge of mechanisms and efficacy in the outcomes of neurohormonal agents in HF with preserved ejection fraction (HFpEF). Recently, type-2 sodium-glucose transporter inhibitors (SGLT2i) have been shown to contribute to a significant reduction in the composite outcome of HF hospitalizations and cardiovascular mortality across the entire spectrum of ejection fraction. Moreover, glucagon-like peptide-1 receptor agonists (GLP1-RA) have demonstrated significant benefits in patients with high cardiovascular risk, excess body weight or obesity and HF, in particular HFpEF. In this review, we will discuss the biological pathways potentially involved in the action of SGLT2i and GLP1-RA, which may explain their effective roles in the treatment of HF, as well as the potential implications of the use of these agents, also in combination therapies with neurohormonal agents, in the clinical practice.

Hyperlipidemia induces proinflammatory responses by activating STING pathway through IRE1α-XBP1 in retinal endothelial cells

Diabetic retinopathy (DR) is one of the most prevalent microvascular complications caused by diabetes mellitus. Previous studies demonstrate that microvascular endothelial inflammation caused by chronic hyperglycemia and hyperlipidemia plays a key role in the pathogenesis of DR. However, the detailed mechanisms on how endothelial inflammation contributes to DR are not fully understood. The STING pathway is an important innate immune signaling pathway. Although STING has been implicated in multiple autoimmune and metabolic diseases, it is not clear whether STING is involved in the pathogenesis of DR. Thus, re-analysis of the public single cell RNA sequencing (sc-RNAseq) data demonstrated that STING was highly expressed in mouse retinal vessels. Moreover, our results demonstrated that STING and p-TBK1 protein levels in retinal endothelial cells are significantly increased in mice fed with high fat diet compared with chow diet. In vitro, palmitic acid treatment on HRVECs induced mitochondrial DNA leakage into the cytosol, and augmented p-TBK1 protein and IFN-β mRNA levels. As STING is localized to the ER, we analyzed the relation between STING activation and ER stress. In HRVECs, STING pathway was shown to be activated under chemical-induced ER stress, but attenuated when IRE1α was abolished by genetic deletion or pharmacological inhibition. Taken together, our findings revealed that STING signaling plays an important role in mediating lipotoxicity-induced endothelial inflammatory and injury, and IRE1α-XBP1 signaling potentiated STING signaling. Thus, targeting the IRE1α or STING pathways to alleviate endothelial inflammation provides candidate therapeutic target for treating DR as well as other microvascular complications.

Tongxinluo enhances the effect of atorvastatin on the treatment of atherosclerosis with chronic obstructive pulmonary disease by maintaining the pulmonary microvascular barrier.

Atherosclerosis (AS) is a common comorbidity of chronic obstructive pulmonary disease (COPD), and systemic inflammation is an important mechanism of COPD with AS. Tongxinluo (TXL) improves the function of vascular endothelial cells. We aimed to prove that impairment of pulmonary microvascular barrier function is involved in COPD-mediated aggravation of AS and investigate whether TXL enhances the effect of Ato (atorvastatin) on COPD with AS by protecting pulmonary microvascular endothelial barrier function. In vivo, a COPD with atherosclerotic apolipoprotein E knockout (AS ApoE-/-) mouse model was established by cigarette smoke combined with a high-fat diet. The animals were administered TXL, Ato, and TXL + Ato once a day for 20 weeks. Lung function, lung microvascular permeability, lung inflammation, systemic inflammation, serum lipid levels, atheromatous plaque formation, and endothelial damage biomarkers were measured. In vitro, human pulmonary microvascular endothelial cells (HPMECs) were pretreated with TXL and incubated with cigarette smoke extract to establish the model. The permeability of the endothelial monolayer, inflammatory cytokines, endothelial damage biomarkers, and tight junction (Tj) proteins were determined. Cigarette smoking significantly exacerbated the high-fat diet-induced pulmonary function decline, pulmonary microvascular endothelial barrier dysfunction, inflammation, and atherosclerotic plaques. These changes were reversed by TXL-Ato; the combination was more effective than Ato alone. Furthermore, TXL protected the HPMEC barrier and inhibited inflammation in HPMECs. COPD aggravates AS, possibly through the destruction of pulmonary microvascular barrier function; thus, lung inflammation triggers systemic inflammation. In treating COPD with AS, TXL enhances the antiatherosclerotic effect of Ato, protecting the pulmonary microvascular barrier.

Cell Therapy in Heart Failure with Preserved Ejection Fraction.

Heart failure with preserved ejection fraction (HFpEF) is the most common cause of hospitalisation for heart failure. However, only limited effective treatments are available. Recent evidence suggests that HFpEF may result from a systemic proinflammatory state, microvascular endothelial inflammation and microvascular rarefaction. Formation of new microvasculature in ischaemic tissues is dependent on CD34+ cells, which incorporate into the newly developing vasculature and produce pro-angiogenic cytokines. In HFpEF patients, worsening of diastolic function appears to correlate with decreased numbers of CD34+ cells. Therefore, it is plausible that increasing the myocardial numbers of CD34+ cells could theoretically lead to improved microvascular function and improved diastolic parameters in HFpEF. In accordance with this hypothesis, recent pilot clinical data suggest that CD34+ cell therapy may indeed be associated with improved diastolic function and better functional capacity in HFpEF patients and could thus represent a promising novel therapeutic modality for this patient population.

Plasma from patients undergoing coronary artery bypass graft surgery does not activate endothelial cells under shear stress in vitro.

Background:Cardiac surgery with cardiopulmonary bypass (CPB) is commonly associated with acute kidney injury, and microvascular endothelial inflammation is a potential underlying mechanism. We hypothesized that pro-inflammatory components of plasma from patients who underwent coronary artery bypass graft surgery with CPB induce endothelial adhesion molecule expression when incorporating altered shear stress in the in vitro model.Methods:The clinical characteristics and markers of systemic inflammation and kidney injury were analyzed pre and postoperatively in 29 patients undergoing coronary artery bypass grafting with CPB. The effects of tumor necrosis factor (TNF)-α and patient plasma on the expression of endothelial inflammation and adhesion markers were analyzed in vitro.Results:Plasma TNF-α was elevated 6 h postoperation (median: 7.3 pg/ml (range: 2.5–94.8 pg/ml)). Neutrophil gelatinase-associated lipocalin in plasma peaked 6 h (99.8 ng/ml (52.6–359.1 ng/ml)) and in urine 24 h postoperation (1.6 ng/mg (0.2–6.4 ng/mg)). Urinary kidney injury molecule-1 concentration peaked 24 h postoperation (0.5 ng/mg (0.2–1.2 ng/mg). In vitro, the expression of E-selectin was induced by 20 pg/ml TNF-α. In addition, the expression of interleukin-8, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 was induced by 100 pg/ml TNF-α. Compared to healthy control plasma exposure, postoperative plasma did not increase the expression of markers of endothelial inflammation and adhesion under shear stress in vitro.Conclusion:Patients undergoing CPB surgery showed mild systemic inflammation and kidney injury. However, the plasma components did not stimulate endothelial inflammation and adhesion molecule expression in vitro.

An herbal preparation ameliorates heart failure with preserved ejection fraction by alleviating microvascular endothelial inflammation and activating NO-cGMP-PKG pathway

BackgroundHeart failure with preserved ejection fraction (HFpEF) is a heterogeneous disease presenting a substantial challenge to clinicians. Currently, there is no safe and efficacious HFpEF treatment. In this study, we reported a standardized herbal medicinal product, QiShenYiQi (QSYQ), that can be used in the treatment of HFpEF. MethodsHFpEF mice were established by infusing a combination of Nω-nitro-L-arginine methyl ester (L-NAME) and feeding them a high-fat diet for 14 weeks. In the 10th week, the HFpEF mice were given dapagliflozin or QSYQ via oral gavage for four weeks. The blood pressure, echocardiography, hemodynamics, leukocyte infiltration, and oxidative stress in HFpEF mice were evaluated. Besides, inflammatory factors, endothelial adhesion factors, and endothelial-mesenchymal transformation (EndMT) markers were investigated. ResultsQSYQ significantly attenuated concentric cardiac remodeling while improving diastolic function and left ventricular compliance in HFpEF mice. QSYQ also inhibited inflammation and immunocyte recruitment during HFpEF. The infiltration of CD8+, CD4+ T cells, and CD11b/c+ monocytes was substantially mitigated in the myocardium of QSYQ-treated mice. TNF-α, MCP-1, NF-κB, and NLRP3 levels also reduced after QSYQ treatment. Furthermore, QSYQ significantly reversed the elevated expression of endothelial adhesion factors and EndMT occurrence. These effects of QSYQ were demonstrated by the activation of NO-cGMP-PKG pathway and reduction of eNOS uncoupling in the HFpEF heart. ConclusionThese results provide novel evidence that QSYQ treatment improves HFpEF by inhibiting microvascular endothelial inflammation and activating NO-cGMP-PKG pathway.

Catecholaminergic Vasopressors Reduce Toll-Like Receptor Agonist-Induced Microvascular Endothelial Cell Permeability But Not Cytokine Production.

Catecholaminergic vasopressors are the cornerstone of circulatory shock management. Nevertheless, catecholamines have problematic side effects, arousing a growing interest in noncatecholaminergic agents such as vasopressin or angiotensin-II. However, their respective effects on sepsis-associated microvascular endothelial dysfunction such as permeability or inflammation remain elusive. We investigated the role of catecholamines and other vasopressors on Toll-like receptor agonists-induced microvascular endothelial permeability and inflammation. University research laboratory/cell research. Human pulmonary microvascular endothelial cells from multiple donors. Confluent monolayers of human pulmonary microvascular endothelial cells were treated with Toll-like receptor agonists (lipopolysaccharide, Poly[I:C], or tripalmitoyl-S-glyceryl cysteine) in the presence or absence of epinephrine, norepinephrine, vasopressin, and angiotensin-II. Permeability was inferred from transendothelial resistance, measured using electrical cell impedance sensing, where decreased transendothelial resistance is consistent with increased permeability. Cell-cell junction molecule expression was assessed via immunofluorescence microscopy and flow cytometry. We quantified cytokines in supernatants of Toll-like receptor agonist-treated human pulmonary microvascular endothelial cells. Epinephrine and norepinephrine both ameliorate lipopolysaccharide, polyinosinic:polycytidylic acid, or tripalmitoyl-S-glyceryl cysteine-induced reductions in transendothelial resistance, a surrogate for endothelial permeability. In contrast, the noncatecholaminergic agents, vasopressin, and angiotensin-II did not affect Toll-like receptor agonists-induced reductions in transendothelial resistance. β1- and β2-adrenergic receptor antagonists reduced the effects of the catecholamines on transendothelial resistance, whereas α-adrenergic receptor antagonists did not. We observed that epinephrine and norepinephrine induced actin cytoskeletal rearrangement and normalized the membrane expression of proteins involved with adherens-junctions (vascular endothelial-cadherin) and tight-junctions (zona occludens-1). Despite having a substantial effect on endothelial permeability, epinephrine and norepinephrine did not affect human pulmonary microvascular endothelial cell survival or production of interleukin-8, interleukin-6, or monocyte chemoattractant protein-1 (CCL-2) induced by Toll-like receptor agonists, suggesting that these functions are regulated separately from permeability. Our findings demonstrate that treatment with epinephrine or norepinephrine strongly reduces endothelial permeability induced by agonists of multiple Toll-like receptors (Toll-like receptor-2, Toll-like receptor-3, Toll-like receptor-4) in vitro. Our studies suggest that both β1- and β2-adrenergic receptors mediate the stabilizing effects of epinephrine and norepinephrine on the endothelial barrier.

Role of coronary microvascular dysfunction in heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) is one of the greatest unmet needs in modern medicine. The lack of an appropriate therapy may reflect the lack of an accurate comprehension of its pathophysiology. Coronary microvascular rarefaction in HFpEF was first hypothesized in an autopsy study that showed how HFpEF patients had lower microvascular density and more myocardial fibrosis than control subjects. This was later confirmed in vivo when it was noted that HFpEF is associated with reduced myocardial flow reserve (MFR) at single photon emission computed tomography (SPECT) and that coronary microvascular dysfunction may play a role in HFpEF disease processes. HFpEF patients were found to have lower coronary flow reserve (CFR) and a higher index of microvascular resistance (IMR). What is the cause of microvascular dysfunction? In 2013, a new paradigm for the pathogenesis of HFpEF has been proposed. It has been postulated that the presence of a proinflammatory state leads to coronary microvascular endothelial inflammation and reduced nitric oxide bioavailability, which ultimately results in heart failure. Recently, it has also been noted that inflammation is the main driver of HFpEF, but via an increase in inducible nitric oxide synthase (iNOS) resulting in a decrease in unfolded protein response. This review summarizes the current evidence on the etiology of coronary microvascular dysfunction in HFpEF, focusing on the role of inflammation and its possible prevention and therapy.

Coronavirus 2019 Disease (COVID-19), Systemic Inflammation, and Cardiovascular Disease.

Acute respiratory failure associated with the Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2), has rapidly spread worldwide and presents critical challenges for the public health and medical communities The World Health Organization (WHO) has declared SARS-CoV-2 a public health emergency of international concern, with a global estimate of over 7 million human infections and more than 400000 deaths worldwide as of June 12, 2020 A 2020 report by the China Medical Treatment Expert Group for Coronavirus disease 2010 (COVID-19) (2) showed that the clinical spectrum of the viral infection is dominated by fever (up to 88 7% of patients during hospitalization) and cough (67 8% of patients) followed by symptoms such as headache, fatigue, or shortness of breath

The Molecular and Cellular Mechanisms Associated with a Microvascular Inflammation in the Pathogenesis of Heart Failure with Preserved Ejection Fraction

Heart failure withpreserved ejection fraction (HFpEF) is a severe disease with an often unfavorable outcome. The prevalence of HFpEF continues to increase, while effective treatment options remain elusive. All the medical strategies used toimprove the outcome in a heart failure with reduced ejection fraction proved ineffective in HFpEF, which was probably due to the different mechanisms ofdevelopment of these two types of heart failure and the diversity of the HFpEF phenotypes. According to the current paradigm of HFpEF development, a chronic mild pro-inflammatory statecauses a coronary microvascular endothelial inflammation, with further myocardial fibrosis and diastolic dysfunction progression. This inflammatory paradigm of HFpEF has been confirmed with someevidence, and suppressing the inflammation may become a novel strategy for treating and managing HFpEF. This review summarizes current concepts about a microvascular inflammation in hypertrophied myocardium and provides a translational perspective of the anti-inflammatory and immunomodulatory approaches in HFpEF.

Metabolomic Profile in HFpEF vs HFrEF Patients

Heart failure with preserved ejection fraction (HFpEF) and HF with reduced ejection fraction (HFrEF) are associated with metabolic derangements, which may have different pathophysiological implications. In new-onset HFpEF (EF of ≥50%, n = 46) and HFrEF (EF of <40%, n = 75) patients, 109 endogenous plasma metabolites including amino acids, phospholipids and acylcarnitines were assessed using targeted metabolomics. Differentially altered metabolites and associations with clinical characteristics were explored. Patients with HFpEF were older, more often female with hypertension, atrial fibrillation, and diabetes compared with patients with HFrEF. Patients with HFpEF displayed higher levels of hydroxyproline and symmetric dimethyl arginine, alanine, cystine, and kynurenine reflecting fibrosis, inflammation and oxidative stress. Serine, cGMP, cAMP, l-carnitine, lysophophatidylcholine (18:2), lactate, and arginine were lower compared with patients with HFrEF. In patients with HFpEF with diabetes, kynurenine was higher (P = .014) and arginine lower (P = .014) vs patients with no diabetes, but did not differ with diabetes status in HFrEF. Decreasing kynurenine was associated with higher eGFR only in HFpEF (Pinteraction = .020). Patients with new-onset HFpEF compared with patients with new-onset HFrEF display a different metabolic profile associated with comorbidities, such as diabetes and kidney dysfunction. HFpEF is associated with indices of increased inflammation and oxidative stress, impaired lipid metabolism, increased collagen synthesis, and downregulated nitric oxide signaling. Together, these findings suggest a more predominant systemic microvascular endothelial dysfunction and inflammation linked to increased fibrosis in HFpEF compared with HFrEF. ClinicalTrials.gov NCT03671122 https://clinicaltrials.gov.

The Molecular and Cellular Mechanisms Associated with a Microvascular Inflammation in the Pathogenesis of Heart Failure with Preserved Ejection Fraction.

Heart failure with preserved ejection fraction (HFpEF) is a severe disease with an often unfavorable outcome. The prevalence of HFpEF continues to increase, while effective treatment options remain elusive. All the medical strategies used to improve the outcome in a heart failure with reduced ejection fraction proved ineffective in HFpEF, which was probably due to the different mechanisms of development of these two types of heart failure and the diversity of the HFpEF phenotypes. According to the current paradigm of HFpEF development, a chronic mild pro-inflammatory state causes a coronary microvascular endothelial inflammation, with further myocardial fibrosis and diastolic dysfunction progression. This inflammatory paradigm of HFpEF has been confirmed with some evidence, and suppressing the inflammation may become a novel strategy for treating and managing HFpEF. This review summarizes current concepts about a microvascular inflammation in hypertrophied myocardium and provides a translational perspective of the anti-inflammatory and immunomodulatory approaches in HFpEF.

Role of adenosine A2b receptors in pulmonary microvascular endothelial inflammation induced by lipopolysaccharide

To explore the role of the low-affinity A2b adenosine receptors (Adora2b) in pulmonary microvascular endothelial inflammation induced by lipopolysaccharide and its mechanism. Rat pulmonary microvascular endothelial cells (PMVECs) were isolated and cultured in vitro. After serum deprivation for 24 hours, cells were pretreated with Adora2b specific agonist BAY60-6583 (0.1, 1, 10 μmol/L) or Adora2b specific antagonist PSB1115 (1 μmol/L) for 1 hour, respectively, and then challenged with LPS (100 μg/L). Cells without treatment were served as the control group, and those treated with LPS, BAY60-6583 or PSB1115 alone were served as single challenge groups. After incubation with specific drugs for 24 hours, the apoptosis of PMVECs was analyzed by flow cytometry using Annexin V/propidium iodide (PI) technique. The levels of early inflammatory factors in cultured medium were measured using enzyme linked immunosorbent assay (ELISA). The mRNA expressions of chemotactic factors and adhesion molecules were determined by real-time quantitative-polymerase chain reaction (RT-qPCR). Polymorph nuclear neutrophils (PMNs) from venous blood of healthy rats were isolated, and PMN migration through PMVECs monolayer under stimulation of drugs was observed in transwell inserts. The monolayer permeability of PMVECs after adhesion of PMNs was determined by fluorescein isothiocyanate (FITC)-albumin assay. Oxidative stress was detected by DCFH-DA assay. Compared with the control group, more cells entered into the apoptosis stage after LPS challenge. Meanwhile, the levels of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in cultured medium were significantly increased, as well as the mRNA expressions of chemotactic factors [C-X-C motif chemokine ligand 1 (CXCL-1), CXCL-3 and monocyte chemoattractant protein-1 (MCP-1)] and adhesion molecules [E-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1)]. More PMNs migrated through PMVECs following adhesion and the monolayer permeability of PMVECs was rapidly enhanced. The oxidative stress was upregulated. Compared with LPS group, BAY60-6583 pretreatment could dose-dependently decrease the rate of apoptosis, attenuate trans-endothelial migration of PMNs and decrease the endothelial cell barrier leakage. There were significant differences even after incubation of 0.1 μmol/L BAY60-6583 [apoptosis rate: (21.12±2.12)% vs. (27.66±3.57)%, number of migrated PMNs/HP: 260.60±18.24 vs. 290.20±16.48, permeability coefficient (Pd, ×10-6 cm/s): 28.28±2.04 vs. 32.55±2.13, all P < 0.05]. Meanwhile, BAY60-6583 pretreatment also downregulated the levels of early proinflammatory factors in a dose-dependent manner as well as the mRNA expressions of chemotactic factors and adhesion molecules. The statistic difference was significant while treated with 1 μmol/L BAY60-6583 [IL-1β (ng/L): 475.75±63.15 vs. 755.25±67.42, TNF-α (ng/L): 560.25±69.96 vs. 818.75±60.92, CXCL-1 mRNA (2-ΔΔCt): 3.57±0.28 vs. 5.27±0.69, CXCL-3 mRNA (2-ΔΔCt): 4.56±0.48 vs. 7.32±0.54, MCP-1 mRNA (2-ΔΔCt): 2.21±0.31 vs. 3.35±0.21, E-selectin mRNA (2-ΔΔCt): 4.64±0.09 vs. 7.28±0.73, ICAM-1 mRNA (2-ΔΔCt): 4.14±0.30 vs. 5.89±0.25, VCAM-1 mRNA (2-ΔΔCt): 2.23±0.19 vs. 2.92±0.33, all P < 0.05]. Furthermore, pretreatment of 10 μmol/L BAY60-6583 could decrease the oxidative stress [reactive oxygen species (RFU): 629.05±33.10 vs. 781.45±64.59, P < 0.05]. Contrast, PSB1115 pretreatment aggravated apoptosis of PMVECs after LPS incubation [(34.36±4.57)% vs. (27.66±3.57)%], upregulated expressions of proinflammatory and chemotactic factors as well as adhesion molecules [IL-1β (ng/L): 889.00±63.11 vs. 755.25±67.42, TNF-α (ng/L): 939.00±43.44 vs. 818.75±60.92, CXCL-1 mRNA (2-ΔΔCt): 6.66±0.65 vs. 5.27±0.69, CXCL-3 mRNA (2-ΔΔCt): 10.42±0.51 vs. 7.32±0.54, MCP-1 mRNA (2-ΔΔCt): 4.85±0.34 vs. 3.35±0.21, E-selectin mRNA (2-ΔΔCt): 8.42±0.47 vs. 7.28±0.73, ICAM-1 mRNA (2-ΔΔCt): 7.46±0.72 vs. 5.89±0.25, VCAM-1 mRNA (2-ΔΔCt): 4.35±0.26 vs. 2.92±0.33], aggravated trans-endothelial migration of PMNs (cells/HP: 348.40±22.68 vs. 290.20±16.48), enhanced the leakage of PMVECs monolayer [Pd (×10-6 cm/s): 39.65±2.69 vs. 32.55±2.13] and increased oxidative stress in PMVECs [reactive oxygen species (RFU): 847.04±29.26 vs. 781.45±64.59], with statistically significant difference (all P < 0.05). Activation of endothelial Adora2b attenuates LPS-induced pulmonary microvascular inflammation by decreasing the release of early inflammatory factors, downregulating expressions of chemotactic factors and adhesion molecules, attenuating trans-endothelial migration of PMNs and oxidative stress in PMVECs, which suggest endothelial Adora2b is apotential anti-inflammatory target in the treatment of LPS-induced acute lung injury.

Biomarkers of Inflammation in Left Ventricular Diastolic Dysfunction.

Left ventricular diastolic dysfunction (LVDD) is an important precursor to many different cardiovascular diseases. Diastolic abnormalities have been studied extensively in the past decade, and it has been confirmed that one of the mechanisms leading to heart failure is a chronic, low-grade inflammatory reaction. The triggers are classical cardiovascular risk factors, grouped under the name of metabolic syndrome (MetS), or other systemic diseases that have an inflammatory substrate such as chronic obstructive pulmonary disease. The triggers could induce myocardial apoptosis and reduce ventricular wall compliance through the release of cytokines by multiple pathways such as (1) immune reaction, (2) prolonged cell hypoxemia, or (3) excessive activation of neuroendocrine and autonomic nerve function disorder. The systemic proinflammatory state causes coronary microvascular endothelial inflammation which reduces nitric oxide bioavailability, cyclic guanosine monophosphate content, and protein kinase G (PKG) activity in adjacent cardiomyocytes favoring hypertrophy development and increases resting tension. So far, it has been found that inflammatory cytokines associated with the heart failure mechanism include TNF-α, IL-6, IL-8, IL-10, IL-1α, IL-1β, IL-2, TGF-β, and IFN-γ. Some of them could be used as diagnosis biomarkers. The present review aims at discussing the inflammatory mechanisms behind diastolic dysfunction and their triggering conditions, cytokines, and possible future inflammatory biomarkers useful for diagnosis.

Ripasudil Attenuates Lipopolysaccharide (LPS)-Mediated Apoptosis and Inflammation in Pulmonary Microvascular Endothelial Cells via ROCK2/eNOS Signaling.

BackgroundMicrovascular endothelial inflammation and apoptosis are responsible for septic acute lung injury (ALI). Ripasudil is a novel Rho/Rho kinase (ROCK) inhibitor which shows therapeutic effects on several vascular diseases. The aim of this study was to investigate the protective effects and correlated molecular mechanisms of ripasudil on lipopolysaccharide-induced inflammation and apoptosis of pulmonary microvascular endothelial cells (PMVECs).Material/MethodsCultured PMVECs were exposed to lipopolysaccharide (LPS). Ripasudil at various concentrations was used to treat the cells. Several cells were also co-administrated with the endothelial nitric oxide synthase (eNOS) inhibitor Nω-Nitro-L-arginine methyl ester hydrochloride (L-NAME). Cell viability was assessed by MTT assay. Terminal dUTP transferase nick-end labeling (TUNEL) assay was used to detect the apoptosis. The colorimetric method was used to measure the activity of eNOS and ROCK2. Protein phosphorylation and expression were assessed by Western blotting.ResultsRipasudil attenuated the LPS-induced inflammation and apoptosis in PMVECs, which was reversed by L-NAME. Ripasudil suppressed ROCK2 activity and further increased the eNOS activity. Ripasudil treatment increased the phosphorylation of eNOS, increased the expression level of Bcl2, and decreased the expression level of active caspase3 in LPS-treated PMVECs. Moreover, the ripasudil treatment also inhibited the nuclear translocation of NF-κB and further suppressed the levels of interleukin (IL) 6 and tumor necrosis factor (TNF) α. The co-treatment with L-NAME, however, impaired the anti-apoptotic and anti-inflammatory effects of ripasudil on PMVECs without affecting ROCK2.ConclusionsThe novel ROCK2 inhibitor ripasudil suppressed LPS-induced apoptosis and inflammation in PMVECs by regulating the ROCK2/eNOS signaling pathway.

Diastolic Dysfunction is Generated in Mice with Knockout of Smoothelin‐like 1 Protein

BACKGROUNDCardiovascular disease (CVD) is the leading cause of morbidity and mortality worldwide. Ultimately, heart failure (HF) is the common final outcome for most patients with CVD, and HF with preserved ejection fraction (HFpEF) has gained increasing prevalence. Clinical evidence associates HFpEF with microvascular dysfunction and endothelial inflammation, which in turn drive pathologic cardiac remodeling. No therapeutics are available for improving outcomes of HFpEF patients; thus, further research is required to better understand its etiology since the molecular pathways leading to HFpEF are not confined to one pathology. Of particular note, our recent experiments reveal a novel role for the smoothelin‐like 1 (SMTNL1) protein in the endothelium which when disturbed drives dramatic alterations in systemic inflammation, endothelial functional responses, and cardiovascular performance.OBJECTIVEThe study examined the impact of SMTNL1 deficiency on cardiac function in male murine models.METHODSSMTNL1 global knockout (KO) mice (10‐week old, young male) were anesthetized by isoflurane and underwent M‐mode echocardiographic (ECG) imaging (Vevo770, Visual Sonics, Canada), followed by left ventricular (LV) catheterization (PVR 1045, Millar Instruments, Houston, TX) and pressure‐volume (PV) loop measurements to assess the systolic‐diastolic and hemodynamic parameters of cardiac function. The background strain 129S6 wildtype (WT) mice served as the control group. Mice were terminated at the end of PV loop procedures, and serum was collected for detection of circulating markers (Luminex array, EveTechnologies Inc.).RESULTSGross dissection revealed distinct cardiac morphology; hearts from KO animals were significantly smaller than WT littermates (~12% smaller HM:TL ratios), but the proportion of heart mass taken up by LV was greater (~10% larger LV:HM ratios). The non‐invasive ECG analysis of KO mice showed normal ejection fraction (%EF: 54.5±3.3 vs 44.0±3.0) and fractional shortening (%FS: 28.2±2.2 vs 21.7±1.7) relative to the WT counterparts. However, PV loop analysis revealed diastolic dysfunction with significantly increased end diastolic pressure (EDP: 11.6±1.7 vs 4.9±1.8 mmHg, p&lt;0.05) and LV relaxation time (Tau; 11.7±0.4 vs 7.0±0.4 ms, p&lt;0.0001) along with a steeper end diastolic PV relationship (EDPVR: 0.55±0.14 vs 0.22±0.06, p&lt;0.05) an indicator of stiffer heart, in KO group when compared to the WT group. Additionally, circulating serum markers such as sE‐selectin and pro‐MMP9 were elevated in the KO mice.CONCLUSIONIn the present study, we have identified intriguing linkages for SMTNL1 and pathophysiological definitions of diastolic dysfunction, and suggest SMTNL1 knockout animals represent a new pre‐clinical model to examine the development of HF‐pEF. However, the pathophysiological role of SMTNL1 protein in the regulation of cardiac hemodynamics, potentially through endothelial inflammation and microvascular dysfunction requires further study.Support or Funding Information ‐Libin Cardiovascular Institute of Alberta, University of Calgary ‐Achievers in Medicine Scholarship from Cumming School of Medicine, University of Calgary ‐CIHR Travel award This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Impact of comorbidities on myocardial remodeling and dysfunction in heart failure with preserved ejection fraction.

Aim. The generalization of the modern data on the influence of comorbidities on cardiac remodeling and heart dysfunction in chronic heart failure (CHF) with preserved ejection fraction (EF). The objectives of the study included the analysis of the pathogenesis of CHF with preserved ejection fraction. Material and methods. Analyzed all Russian and English literature, submitted to the search engines. Results. Analysis of scientific literature showed that the increase in systemic vascular inflammation, endothelial dysfunction and oxidative stress lead to reduced bioavailability of nitric oxide , which leads to increased stiffness of the left ventricle and adverse remodeling of the heart in CHF with preserved ejection fraction. Comorbidities such as overweight /obesity, diabetes, hypertension, chronic obstructive pulmonary disease, anaemia and chronic renal dysfunction leads to coronary remodeling in microvascular endothelial inflammation. The negative contribution is also made by demographic factors such as older age and female gender. In the present review substantiates the crucial role of comorbidities in the pathophysiology of CHF with preserved ejection fraction. Conclusion. Summarizing the analysis of literature sources, devoted to the pathogenesis of CHF with comorbidity, the findings that, in addition to diastolic dysfunction of the left ventricle, there are other patofiziologiia mechanisms: the violation of backup functions, the violation of jeludochno-blood relationship, the energy deficit of the myocardium, pulmonary hypertension, chronotropic imbalance, inflammation, oxidative stress and endothelial dysfunction. With CHF with preserved ejection fraction comorbidities contribute to systemic inflammation which causes oxidative stress in the coronary microvascular endothelium. This reduces the bioavailability of nitric oxide in the myocardium and leads to reduced activity of protein kinase G in cardiomyocytes, which therefore become stiff and hypertrophied. In addition, with increasing age and postmenopausal hormonal changes may lead to additional structural and functional changes.

Risk of Heart Failure With Preserved Ejection Fraction in Older Women After Contemporary Radiotherapy for Breast Cancer.

Cardiomyocytes are resistant to radiation. However, cardiac radiation exposure causes coronary microvascular endothelial inflammation, a perturbation implicated in the pathogenesis of heart failure (HF) and particularly HF with preserved ejection fraction (HFpEF). Radiotherapy for breast cancer results in variable cardiac radiation exposure and may increase the risk of HF. We conducted a population-based case-control study of incident HF in 170 female residents of Olmsted County, Minnesota (59 cases and 111 controls), who underwent contemporary (1998-2013) radiotherapy for breast cancer with computed tomography-assisted radiotherapy planning. Controls were matched to cases for age, tumor side, chemotherapy use, diabetes mellitus, and hypertension. Mean cardiac radiation dose (MCRD) in each patient was calculated from the patient's computed tomography images and radiotherapy plan. Mean age at radiotherapy was 69±9 years. Of HF cases, 38 (64%) had EF≥50% (HFpEF), 18 (31%) had EF<50% (HF with reduced EF), and 3 (5%) did not have EF measured. The EF was ≥40% in 50 of the 56 HF cases (89%) with an EF measurement. The mean interval from radiotherapy to HF was 5.8±3.4 years. The odds of HF was higher in patients with a history of ischemic heart disease or atrial fibrillation. The MCRD was 2.5 Gy (range, 0.2-13.1 Gy) and higher in cases (3.3±2.7 Gy) than controls (2.1±2.0 Gy; P=0.004). The odds ratio (95% confidence interval) for HF per log MCRD was 9.1 (3.4-24.4) for any HF, 16.9 (3.9-73.7) for HFpEF, and 3.17 (0.8-13.0) for HF with reduced EF. The increased odds of any HF or HFpEF with increasing MCRD remained significant after adjustment for HF risk factors and in sensitivity analyses matching by cancer stage rather than tumor side. Only 18.6% of patients experienced new or recurrent ischemic events between radiotherapy and the onset of HF. The relative risk of HFpEF increases with increasing cardiac radiation exposure during contemporary conformal breast cancer radiotherapy. These data emphasize the importance of radiotherapy techniques that limit MCRD during breast cancer treatment. Moreover, these data provide further support for the importance of coronary microvascular compromise in the pathophysiology of HFpEF.

Zooming in on the Microvasculature in Heart Failure With Preserved Ejection Fraction

Heart failure (HF) with preserved ejection fraction (HFpEF) has traditionally been viewed as a form of hypertensive heart disease with increased left ventricular (LV) afterload ultimately leading to HFpEF. However, HFpEF patients typically have numerous other comorbidities.1 Although the severity of LV remodeling and ventricular vascular dysfunction2 and the rate of adverse outcomes3 are greater in patients with HFpEF than in patients with comorbidities alone, some argue that HFpEF is not a distinct syndrome but rather a collection of comorbidities masquerading as HF. See Article by Srivaratharajah et al More recently, based on integrative physiological studies in human HFpEF, the biology of nitric oxide–cyclic guanosine monophosphate–protein kinase G signaling, and elegant studies of human HFpEF myocardium, Paulus and Tschope synthesized an alternate HFpEF pathophysiologic paradigm.1 This paradigm postulates that multimorbidity creates a systemic proinflammatory milieu, coronary microvascular endothelial inflammation, and migration of inflammatory cells to the myocardium with production of proinflammatory cytokines, myocardial inflammation, and subsequent fibrosis. Further, they propose that microvascular endothelial inflammation promotes oxidative stress with generation of oxidative/nitrosative species, which limits myocardial nitric oxide–cyclic guanosine monophosphate–protein kinase G signaling by diminishing nitric oxide bioavailability and oxidizing downstream nitric oxide targets, thus promoting cardiomyocyte hypertrophy. Impaired protein kinase G activity and peroxynitrite-stimulated phosphatases are proposed to alter the phosphorylation status of proteins that influence myofiber relaxation and stiffness and, thus, further impair LV diastolic function. This paradigm has sparked great interest in therapies that target impaired myocardial cyclic guanosine monophosphate–protein kinase G signaling in HFpEF. However, the Paulus paradigm has an important correlate in that an established consequence of coronary microvascular endothelial inflammation is impaired coronary microvascular endothelial function and ultimately coronary microvascular remodeling and rarefaction with decreased microvascular density (MVD).4 The potential impact of diffuse microvascular endothelial inflammation on the functional and …

Is enhancing cGMP-PKG signalling a promising therapeutic target for heart failure with preserved ejection fraction?

Heart failure with preserved ejection fraction, i.e. HFpEF, is highly prevalent in ageing populations, accounting for more than 50 % of all cases of heart failure in Western societies, and is closely associated with comorbidities such as obesity, diabetes and arterial hypertension. However, all large multicentre trials of potential HFpEF treatments conducted to date have failed to produce positive outcomes. These disappointing results suggest that a ‘one size fits all’ strategy may be ill-suited to HFpEF and support the use of tailored, personalised therapeutic approaches with specific treatments designed for specific comorbidity-related HFpEF phenotypes. The accumulation of a multitude of cardiovascular comorbidities over time leads to increased systemic inflammation, oxidative stress and coronary microvascular endothelial inflammation, eventually resulting in degradation of cyclic guanosine monophosphate (cGMP) via multiple pathways, thereby reducing protein kinase G (PKG) activity. The importance of cGMP-PKG pathway modulation is supported by growing evidence that suggests that this pathway may be a promising therapeutic target, evidence that is mainly based on its role in the phosphorylation of the giant cytoskeletal protein titin. This review will focus on the preclinical and early clinical evidence in the field of cGMP-enhancing therapies and PKG activation.