Vascular pharmacology最新文献

Aims

To identify the cardiac biogenic amine profile of obese rats and associate these compounds with parameters of cardiovascular disease.

Main methods

Wistar rats (n = 20) were randomly distributed into two groups: control and obese. Obesity was induced by a high-sugar fat diet. Biochemical parameters were evaluated. Doppler Echocardiography and systolic blood pressure; interleukin-10 (IL-10), tumor necrosis factor-alpha (TNF-α), protein carbonylation, ferric reducing antioxidant power (FRAP), and catalase activity were measured in cardiac tissue. HPLC evaluated the cardiac biogenic profile. Data were compared using the Student's T or Mann-Whitney tests and Spearman's correlation at 5% significance. The principal component analysis (PCA) was performed.

Key findings

Obesity generated hypertension, cardiac remodeling and dysfunction, and imbalanced all biochemical, inflammatory, and oxidative markers (p < 0.001). Eight biogenic amines were found in cardiac tissue. Obesity increased serotonin and decreased agmatine, putrescine, cadaverine, and spermidine. Serotonin (r = 0.534 to 0.808) was strong and positively correlated with obesity, biochemical parameters, cardiac inflammation, oxidative stress, hypertension, cardiac remodeling, and dysfunction (p < 0.001). Spermidine (r = −0.560 to −0.680), putrescine (r = −0.532 to −0.805), cadaverine (r = −0.534 to −0.860), and agmatine (r = −0.579 to −0.884) were inversely correlated with the same parameters (p < 0.001). PCA allowed for distinguishing the control and obese groups.

Significance

There are strong correlations between cardiac biogenic amine levels, cardiac remodeling, and dysfunction resulting from obesity.

Conclusion

There is an association between cardiac biogenic amines and cardiovascular disease in obesity. In addition, agmatine, putrescine, cadaverine, and, mainly, serotonin may be new biomarkers for cardiovascular health in obesity and help to improve the diagnosis and treatment of CVD resulting or not from obesity. However, more research is needed to support this conclusion.

Introduction

Tafamidis is a molecular chaperone that stabilizes the transthyretin (TTR) homo-tetramer, preventing its dissociation and consequent deposition as amyloid fibrils in organ tissues. Tafamidis reduces mortality and the incidence of hospitalization for cardiovascular causes in patients with TTR amyloid (ATTR) cardiomyopathy. As ATTR cardiomyopathy is associated with a high risk of thromboembolic complications, we hypothesized that tafamidis may have a direct ancillary anti-thrombotic effect.

Methods

Primary human aortic endothelial cells (HAECs) were treated with tafamidis at clinically relevant concentrations and with plasma of patients, before and after the initiation of treatment with tafamidis. The expression of TF was induced by incubation with Tumor Necrosis Factor α (TNFα). Intracellular expression of tissue factor (TF) was measured by western blot. TF activity was measured by a colorimetric assay. Gene expressions of TF were measured by quantitative polymerase chain reaction.

Results

Treatment with tafamidis dose-dependently reduced the expression and activity of TNFα-induced TF. This effect was confirmed in cells treated with patients' plasma. Signal Transducer and Activator of Transcription 3 (STAT3) phosphorylation was significantly inhibited by tafamidis. Incubation of HAECs with tafamidis and the STAT3 activator colivelin partially rescued the expression of TF.

Conclusions

Treatment with tafamidis lowers the thrombotic potential in human primary endothelial cells by reducing TF expression and activity. This previously unknown off-target effect may provide a novel mechanistic explanation for the lower number of thromboembolic complications in ATTR cardiomyopathy patients treated with tafamidis.

Aims

Advanced heart failure (AdvHF) poses significant treatment challenges, particularly when mechanical circulatory support or transplant options are unavailable, highlighting a gap in evidence-based medical management. The aim of this study was to evaluate the safety and effectiveness of sodium nitroprusside infusion (SNP) for enhancing systemic and renal perfusion in patients with AdvHF, with or without concomitant inotropic support.

Methods and results

We retrospectively analyzed the medical records of 406 patients with AdvHF admitted between October 2014 and September 2018 who received nocturnal SNP infusions for at least one week. In 55 patients with symptomatic hypotension or signs of peripheral hypoperfusion (differential systemic BP < 15 mmHg), continuous dobutamine infusion was added. In a subset of 155 patients who required multiple hospitalizations (median 3), data from the last hospitalization were used. No symptomatic hypotension leading to discontinuation of SNP (mean dose: 0.5 ± 0.1 μg/kg/min) was reported. Patients showed a significant increase in differential systemic blood pressure after infusion (29.2 ± 8.1 to 36.8 ± 11.6 mmHg, p < 0.001) independent of dobutamine use.

Administration of SNP and dobutamine resulted in greater weight loss compared to SNP alone (−5.33 ± 7.02 vs −3.32 ± 4.0 kg, p < 0.003), but it was also associated with a significant increase in creatinine levels compared to SNP alone (+0.24 ± 0.87 vs +0.02 ± 0.43, p = 0.005).

Conclusions

The results show that SNP is a safe therapeutic choice in AdvHF patients with or without concomitant inotropic support and highlight the potential efficacy of nitroprusside in improving systemic and renal perfusion in these advanced patients.

Increased proliferation and reduced apoptosis of pulmonary artery smooth muscle cells (PASMCs) is recognised as a universal hallmark of pulmonary arterial hypertension (PAH), in part related to the association with reduced pyruvate dehydrogenase (PDH) activity, resulting in decreased oxidative phosphorylation of glucose and increased aerobic glycolysis (Warburg effect). Perhexiline is a well-recognised carnitine palmitoyltransferase-1 (CPT1) inhibitor used in cardiac diseases, which reciprocally increases PDH activity, but is associated with variable pharmacokinetics related to polymorphic variation of the cytochrome P450-2D6 (CYP2D6) enzyme, resulting in the risk of neuro and hepatotoxicity in ‘slow metabolisers’ unless blood levels are monitored and dose adjusted. We have previously reported that a novel perhexiline fluorinated derivative (FPER-1) has the same therapeutic profile as perhexiline but is not metabolised by CYP2D6, resulting in more predictable pharmacokinetics than the parent drug. We sought to investigate the effects of perhexiline and FPER-1 on PDH flux in PASMCs from patients with PAH. We first confirmed that PAH PASMCs exhibited increased cell proliferation, enhanced phosphorylation of AKT^Ser473, ERK 1/2^{Thr202/Tyr204} and PDH-E1α^Ser293, indicating a Warburg effect when compared to healthy PASMCs. Pre-treatment with perhexiline or FPER-1 significantly attenuated PAH PASMC proliferation in a concentration-dependent manner and suppressed the activation of the AKT^Ser473 but had no effect on the ERK pathway. Perhexiline and FPER-1 markedly activated PDH (seen as dephosphorylation of PDH-E1α^Ser293), reduced glycolysis, and upregulated mitochondrial respiration in these PAH PASMCs as detected by Seahorse analysis. However, both perhexiline and FPER-1 did not induce apoptosis as measured by caspase 3/7 activity. We show for the first time that both perhexiline and FPER-1 may represent therapeutic agents for reducing cell proliferation in human PAH PASMCs, by reversing Warburg physiology.

Aims

Neutrophils perform various functions in a circadian-dependent manner; therefore, we investigated here whether the effect of alpha1-antitrypsin (AAT), used as augmentation therapy, is dependent on the neutrophil circadian clock. AAT is a vital regulator of neutrophil functions, and its qualitative and/or quantitative defects have significant implications for the development of respiratory diseases.

Methods

Whole blood from 12 healthy women age years, mean (SD) 29.92 (5.48) was collected twice daily, 8 h apart, and incubated for 30 min at 37 °C alone or with additions of 2 mg/ml AAT (Respreeza) and/or 5 μg/ml lipopolysaccharide (LPS) from Escherichia coli. Neutrophils were then isolated to examine gene expression, migration and phagocytosis.

Results

The expression of CD14, CD16, CXCR2 and SELL (encoding CD62L) genes was significantly higher while CDKN1A lower in the afternoon than in the morning neutrophils from untreated blood. Neutrophils isolated in the afternoon had higher migratory and phagocytic activity. Morning neutrophils isolated from AAT-pretreated blood showed higher expression of CXCR2 and SELL than those from untreated morning blood. Pretreatment of blood with AAT enhanced migratory properties of morning but not afternoon neutrophils. Of all genes analysed, only CXCL8 expression was strongly upregulated in morning and afternoon neutrophils isolated from LPS-pretreated blood, whereas CXCR2 expression was downregulated in afternoon neutrophils. The addition of AAT did not reverse the effects of LPS.

Significance

The circadian clock of myeloid cells may affect the effectiveness of various therapies, including AAT therapy used to treat patients with AAT deficiency, and needs further investigation.

Background

Several factors contribute to ischemia/reperfusion injury (IRI), including activation of the NLRP3 inflammasome and its byproducts, such as interleukin-1β (IL-1β) and caspase-1. However, NLRP3 may paradoxically exhibit cardioprotective properties. This study aimed to assess the protective effects of the novel NLRP3 inhibitor, INF195, both in vitro and ex vivo.

Methods

To investigate the relationship between NLRP3 and myocardial IRI, we synthetized a series of novel NLRP3 inhibitors, and investigated their putative binding mode via docking studies. Through in vitro studies we identified INF195 as optimal for NLRP3 inhibition. We measured infarct-size in isolated mouse hearts subjected to 30-min global ischemia/one-hour reperfusion in the presence of three different doses of INF195 (5, 10, or 20-μM). We analyzed caspase-1 and IL-1β concentration in cardiac tissue homogenates by ELISA. Statistical significance was determined using one-way ANOVA followed by Tukey's test.

Results and conclusion

INF195 reduces NLRP3-induced pyroptosis in human macrophages. Heart pre-treatment with 5 and 10-μM INF195 significantly reduces both infarct size and IL-1β levels. Data suggest that intracardiac NLRP3 activation contributes to IRI and that low doses of INF195 exert cardioprotective effects by reducing infarct size. However, at 20-μM, INF195 efficacy declines, leading to a lack of cardioprotection. Research is required to determine if high doses of INF195 have off-target effects or dual roles, potentially eliminating both harmful and cardioprotective functions of NLRP3. Our findings highlight the potential of a new chemical scaffold, amenable to further optimization, to provide NLRP3 inhibition and cardioprotection in the ischemia/reperfusion setting.

Purpose

Performing non-invasive carotid imaging is challenging, owing inter-operator variability and organizational barriers, but plasma proteomics can offer an alternative. We sought plasma proteins that associate with the presence of carotid plaques, their number and predict the incidence of clinically overt atherosclerotic cardiovascular events (ASCVD) above currently recognized risk factors in “apparently healthy” subjects.

Methods

We studied the plasma levels of 368 proteins in 664 subjects from the PLIC study, who underwent an ultrasound imaging screening of the carotids to check for the presence of plaques. We clustered, by artificial intelligence (A.I.), the proteins that associate with the presence, the number of plaques and that predict incident ASCVDs over 22 years (198 events were registered).

Findings

299/664 subjects had at least 1 carotid plaque (1+) (77 with only one plaque, 101 with 2 plaques, 121 with ≥3 plaques (3+)). The remaining 365 subjects with no plaques acted as controls. 106 proteins were associated with 1+ plaques, but 97 proteins significantly predicted 3+ plaques only (AUC = 0.683 (0.601–0.785), p < 0.001), when considered alone.

A.I. underscored 87 proteins that improved the performance of the classical risk factors both in detecting 3+ plaques (AUC = 0.918 (0.887–0.943) versus risk factors alone, AUC = 0.760 (0.716–0.801), p < 0.001) and in predicting the incident ASCVD (AUC = 0.739 (0.704–0.773) vs risk factors alone AUC = 0.559 (0.521–0.598), p < 0.001). The chemotaxis/migration of leukocytes and interleukins/cytokines signaling were biological pathways mostly represented by these proteins.

Discussion and conclusions

Plasma proteomics marks the number of carotid plaques and improve the prediction of incidence ASCVDs in apparently healthy subjects.

Capillaries are the smallest blood vessels (<10 μm in diameter) in the body and their walls are lined by endothelial cells. These microvessels play a crucial role in nutrient and gas exchange between blood and tissues. Capillary endothelial cells also produce vasoactive molecules and initiate the electrical signals that underlie functional hyperemia and neurovascular coupling. Accordingly, capillary function and density are critical for all cell types to match blood flow to cellular activity. This begins with the process of angiogenesis, when new capillary blood vessels emerge from pre-existing vessels, and ends with rarefaction, the loss of these microvascular structures. This review explores the mechanisms behind these processes, emphasizing their roles in various microvascular diseases and their impact on surrounding cells in health and disease. We discuss recent work on the mechanisms controlling endothelial cell proliferation, migration, and tube formation that underlie angiogenesis under physiological and pathological conditions. The mechanisms underlying functional and anatomical rarefaction and the role of pericytes in this process are also discussed. Based on this work, a model is proposed in which the balance of angiogenic and rarefaction signaling pathways in a particular tissue match microvascular density to the metabolic demands of the surrounding cells. This negative feedback loop becomes disrupted during microvascular rarefaction: angiogenic mechanisms are blunted, reactive oxygen species accumulate, capillary function declines and eventually, capillaries disappear. This, we propose, forms the foundation of the reciprocal relationship between vascular density, blood flow, and metabolic needs and functionality of nearby cells.