The role of endothelin-1 and endothelin receptor antagonists in inflammatory response and sepsis

The role of endothelin receptor antagonists in kidney disease

Kidney diseases are among the most prevalent conditions worldwide, impacting over 850 million individuals. They are categorized into acute kidney injury and chronic kidney disease. Current preclinical and clinical trials have demonstrated that endothelin (ET) is linked to the onset and progression of kidney disease. In kidney diseases, pathological conditions such as hyperglycemia, acidosis, insulin resistance, and elevated angiotensin II levels lead to an increase in ET. This elevation activates endothelin receptor type A, resulting in harmful effects like proteinuria and a reduced glomerular filtration rate (GFR). Therefore, to slow the progression of kidney disease, endothelin receptor antagonists (ERAs) have been proposed as promising new therapies. Numerous studies have demonstrated the efficacy of ERAs in significantly reducing proteinuria and improving GFR, thereby slowing the progression of kidney diseases. This review discusses the mechanisms of action of ERAs in treating kidney disease, their efficacy and safety in preclinical and clinical studies, and explores future prospects for ERAs.

Endothelin System Blockade Extenuates Sepsis-Induced Acute Heart and Kidney Injuries via Modulating ET-1/Klotho/p38-MAPK

Sepsis-induced organ failure is a major health problem, characterised by massive inflammatory and oxidative stress responses. Endothelin-1 (ET-1) is one of the peptides expressed during septicemia with proapoptotic, proinflammatory, and oxidant effects. ET-1 plays a role in heart and kidney injuries in sepsis. Accordingly, the current study was conducted to investigate, on a mechanistic basis, whether inhibition of ET-1 signalling either by blocking its receptors or inhibiting its formation attenuates sepsis-induced acute cardiorenal injuries. To analyse the role of ET-1 in sepsis, we used a cecal ligation and puncture (CLP) model of sepsis. The animals were divided into five groups: CLP non-treated group, CLP-treated groups with bosentan, ambrisentan, and phosphoramidon (30, 5, and 0.5 mg/kg, respectively), and sham-operated group. In addition to the same set of groups, survival analysis was assigned Survival rate, histopathological assessment, and cardiorenal functions were analysed. Oxidant and antioxidant activities, ET-1, IL-6, and lactate were measured. The expression of TNF-α, p38, Klotho, and caspase-3 was evaluated by immunohistochemistry. CLP caused acute cardiorenal damage, high mortality, upregulated levels of ET-1, IL-6, and lactate, as well as an imbalance in oxidant/antioxidant activities, elevated expression of TNF-α, p38, caspase-3 and reduced expression of klotho. Bosentan, ambrisentan, or phosphoramidon improved survival, reduced the levels of inflammatory and oxidative stress parameters, improved cardiorenal functions and structure, elevated the tissue contents of GSH and SOD, raised the expression of klotho protein, and reduced the cardiorenal expression of p38, TNF-α and caspase-3. Endothelin receptor antagonists (ERAs); bosentan and ambrisentan, or endothelin converting enzyme inhibitor (ECE-i) phosphoramidon, are promising agents against sepsis-induced organ damage. This was evident in their cardiorenal protective effects, up-regulation of klotho, suppression of inflammation, oxidation, apoptosis, and enhancement of the antioxidant status.

Metabolic and vascular insulin resistance: partners in the pathogenesis of cardiovascular disease in diabetes

Vascular insulin resistance has emerged as a pivotal factor in the genesis of cardiovascular disease (CVD) in people with diabetes. It forms a complex pathogenic partnership with metabolic insulin resistance to significantly amplify the CVD risk of diabetes and other affected populations. Metabolic insulin resistance (characterized by quantitatively diminished insulin action on glucose metabolism in skeletal muscle, liver, and adipose tissue) is a hallmark of diabetes, obesity, and related conditions. In contrast, vascular insulin resistance is a less appreciated and not well-quantified complication of these conditions. Importantly, an impaired vascular response to insulin contributes directly to vascular dysfunction and over 40 years of research has convincingly shown that vascular and metabolic insulin resistance synergize to create an environment that predisposes individuals to CVD. In this review, we examine the multifaceted vascular actions of insulin, including its roles in regulating blood pressure, blood flow, endothelial health, and arterial stiffness. We also examine how these processes become disrupted in the setting of vascular insulin resistance, which subsequently undermines endothelial function, compromises tissue microvascular perfusion, and promotes vascular rigidity and atherosclerosis. We then highlight potential therapeutic strategies with demonstrated efficacy to improve vascular insulin sensitivity in people with diabetes and suggest that targeting disordered vascular insulin signaling holds promise not only for refining the functional understanding of vascular insulin resistance but also for developing innovative treatments with potential to reduce CVD risk and improve cardiovascular outcomes in people with diabetes.

Mechanistic insights into the protective potential of ambrisentan against L-arginine induced acute pancreatitis and multiorgan damage (role of NRF2/HO-1 and TXNIP/NLRP3 pathways)

Acute pancreatitis (AP) is an abrupt inflammation of the pancreatic tissue. The severity of AP varies from mild and self-limiting to severe, potentially fatal, and can affect several organ systems. The most severe type of AP causes multiple organ damage (MOD) due to systemic inflammation. In this study, ambrisentan (AMB), an endothelin A receptor antagonist (ETA), was investigated for its potential to ameliorate L-arginine (L-Arg) induced AP and MOD in rats. AP was induced using L-Arg (100 mg/100 g). Two doses of AMB were tested and compared to N-acetylcystiene (NAC) effect. AMB restored the normal structure of the pancreatic, hepatic, pulmonary, and renal tissues. In addition, it normalized the levels of pancreatic enzymes, lactate dehydrogenase (LDH), serum liver enzymes, and kidney biomarkers. Furthermore, AMB corrected the imbalance in the levels of oxidants/antioxidants caused by L-Arg. In contrast, AMB (5 mg/kg) significantly upregulated the protein levels of adenosine monophosphate protein kinase (AMPK), nuclear factor erythroid 2-related factor 2 (NRF2), heme oxidase-1(HO-1) and thioredoxin reductase 1 (TXNRD1) by approximately 69.59 %, 85.14 %, 688 % and 96 % respectively, compared with those in rats treated with L-Arg. Furthermore, AMB (5 mg/kg) significantly lowered the thioredoxin-interacting protein (TXNIP), nod-like Receptor Protein 3 (NLRP3), glycogen synthase kinase-3β (GSK-3β), inducible nitric oxide synthase (iNOS), tumor necrosis factor-α (TNF-α), CD68, autophagic markers (P62 and LC3) and apoptotic marker caspase 3 by around 62.43 %, 73.56 %, 62.5 %,70 %, 80.3 %, 93 %, 96.7 %, 95 %, 39.6 % respectively, compared to the group treated with L-Arg. AMB effectively improved the AP and MOD produced by L-Arg through its anti-inflammatory and antioxidant properties. NRF2/HO-1 and TXNIP/NLRP3 pathways play major roles in these protective effects.

Glycoside components promote endothelial progenitor cell-derived exosomes repairing damaged vascular endothelium via the PI3K/AKT signaling pathway

OBJECTIVE

This paper investigated the effects of three glycosides-astragaloside IV, amygdalin, and paeoniflorin (AAP)-derived from Buyang Huanwu Decoction combined with endothelial progenitor cell-derived exosomes (EPC-Exo), on vascular endothelial repair in rats following balloon-induced injury, with specific focus on the PI3K/AKT signaling pathway.

METHODS

Endothelial progenitor cells (EPC) were isolated, cultured, and identified using immunofluorescence, with EPC-Exo being validated through Western blotting (WB), transmission electron microscopy, and particle size analysis. A rat model of endothelial injury was established using a HFD and carotid artery balloon injury (CABI). The rats were subsequently treated with AAP and/or EPC-Exo. Vascular repair was evaluated using hematoxylin-eosin (H&E) staining, ELISA, immunofluorescence, and WB. In vitro, endothelial cell injury was induced, and treatment effects were analyzed using CCK-8, scratch assays, tube formation assays, immunofluorescence, and WB. The involvement of the PI3K/AKT pathway was verified using the PI3K inhibitor LY294002.

RESULTS

The combination of AAP and EPC-Exo significantly reduced intimal hyperplasia, improved endothelial function, and promoted angiogenesis. Network pharmacology and molecular docking analyses demonstrated strong interactions between AAP and PI3K/AKT-related proteins. By enhancing the uptake of EPC-Exo by vascular endothelial cells (VEC), AAP promoted proliferation, migration, and tube formation in vitro while reducing Cleaved-caspase 3 expression. This combination also increased activation of the PI3K/AKT signaling pathway. The PI3K inhibitor weakened these effects, verifying the pathway's involvement in vascular repair.

CONCLUSION

The combination of AAP and EPC-Exo synergistically promotes vascular endothelial repair and angiogenesis, partly by enhancing EPC-Exo uptake through activation of the PI3K/AKT signaling pathway.

Temporal immune profiling in the cerebrospinal fluid and blood of patients with aneurysmal subarachnoid hemorrhage

Delayed cerebral ischemia (DCI) is a significant complication of aneurysmal subarachnoid hemorrhage (aSAH). This study profiled immune responses after aSAH and evaluated their association with DCI onset. Twelve aSAH patients were enrolled. Leukocyte populations and cytokine levels were analyzed in cerebrospinal fluid (CSF) and peripheral blood (PB) on days 3, 5, 7, 10, and 14 post-aSAH. PB mononuclear cells (PBMCs) were collected, and their cytokine production quantified following stimulation. Mixed-effects models reveal distinct immune cell dynamics in CSF compared with blood. Monocyte/macrophage numbers continue to increase in both CSF and PBMCs for days post-aSAH. CD4+ human leukocyte antigen II+ T cells and CD8+ CD154+ T cells increased in circulation over time. Unstimulated PBMCs showed increased interleukin (IL)-1β, IL-6, and tumor necrosis factor alpha production, peaking at 7 d post-aSAH, coinciding with typical DCI onset. Ex vivo stimulation of PBMCs showed that only IL-6 significantly changed over time. In CSF, cytokines peaked 5 d postinjury, preceding immune cell profile alterations. Our findings reveal a time-dependent immune response following aSAH, with distinct within-patient patterns in CSF and PB. The early CSF cytokine peak preceding immune cell changes suggests a potential mechanistic link and identifies the cytokine response as a potential therapeutic target. This cytokine surge may drive immune cell expansion and prime PBMCs for increased inflammatory activity, potentially contributing to DCI risk. Future studies should explore the importance and sources of specific cytokines in driving immune activation. These insights may inform the development of targeted immunomodulatory strategies for preventing or managing DCI in aSAH patients.

New rat model of spinal cord infarction with long-lasting functional disabilities generated by intraspinal injection of endothelin-1

BACKGROUND

The current method for generating an animal model of spinal cord (SC) infarction is highly invasive and permits only short-term observation, typically limited to 28 days.

OBJECTIVE

We aimed to establish a rat model characterised by long-term survival and enduring SC dysfunction by inducing selective ischaemic SC damage.

METHODS

In 8-week-old male Wistar rats, a convection-enhanced delivery technique was applied to selectively deliver endothelin-1 (ET-1) to the anterior horn of the SC at the Th13 level, leading to SC infarction. The Basso, Beattie and Bresnahan (BBB) locomotor score was assessed for 56 days. The SC was examined by a laser tissue blood flowmeter, MRI, immunohistochemistry, triphenyl tetrazolium chloride (TTC) staining, Western blots and TUNEL staining.

RESULTS

The puncture method was used to bilaterally inject 0.7 µL ET-1 (2.5 mg/mL) from the lateral SC into the anterior horns (40° angle, 1.5 mm depth) near the posterior root origin. Animals survived until day 56 and the BBB score was stably maintained (5.5±1.0 at day 14 and 6.2±1.0 at day 56). Rats with BBB scores ≤1 on day 1 showed stable scores of 5-6 after day 14 until day 56 while rats with BBB scores >1 on day 1 exhibited only minor dysfunction with BBB scores >12 after day 14. TTC staining, immunostaining and TUNEL staining revealed selective ischaemia and neuronal cell death in the anterior horn. T2-weighted MR images showed increasing signal intensity at the SC infarction site over time. Western blots revealed apoptosis and subsequent inflammation in SC tissue after ET-1 administration.

CONCLUSIONS

Selective delivery of ET-1 into the SC allows for more precise localisation of the infarcted area at the targeted site and generates a rat SC infarction model with stable neurological dysfunction lasting 56 days.

Development of a Long-Acting Interleukin-11 Antagonist for the Treatment of Renal Fibrosis

Renal fibrosis, a key progression of chronic kidney disease (CKD), remains a major challenge in nephrology, with no FDA-approved drugs specifically targeting this condition. Interleukin-11 (IL-11) has emerged as a potential therapeutic target for renal fibrosis. In this study, we identified the antifibrotic effects of a recombinant human IL-11 analogue, IL-11-6M, in a mouse model of unilateral ureteral obstruction (UUO). We generated additional IL-11-6M variants via an optimized Escherichia coli expression system, with one variant (D46C) exhibiting comparable efficacy. Further modified through cysteine-specific PEGylation, analogue 13 demonstrated similar potency to IL-11-6M with an IC50 value of 61.5 ± 26.2 nM and maintained strong binding affinity to IL-11Rα (KD = 3.0 nM). Notably, analogue 13 exhibited a prolonged half-life and showed significant therapeutic effects in the UUO-induced renal fibrosis model. These findings suggest analogue 13 should be a promising candidate for the treatment of renal fibrosis.

Thinking Outside the Therapeutic Box: The Potential of Polyphenols in Preventing Chemotherapy-Induced Endothelial Dysfunction

The numerous side effects and adverse health implications associated with chemotherapies have long plagued the field of cancer care. Whilst in some cases a curative measure, this highly toxic intervention consistently scores poorly on quantitative measures of tolerability and safety. Of these side effects, cardiac and microvascular defects pose the greatest health risk and are the leading cause of death amongst cancer survivors who do not succumb to relapse. In fact, in many low-grade cancers, the risk of recurrence is far outweighed by the cardiovascular risk of morbidity. As such, there is a pressing need to improve outcomes within these populations. Polyphenols are a group of naturally occurring metabolites that have shown potential vasoprotective effects. Studies suggest they possess antioxidant and anti-inflammatory activities, in addition to directly modulating vascular signalling pathways and gene expression. Leveraging these properties may help counteract the vascular toxicity induced by chemotherapy. In this review, we outline the main mechanisms by which the endothelium is damaged by chemotherapeutic agents and discuss the ability of polyphenols to counteract such side effects. We suggest future considerations that may help overcome some of the published limitations of these compounds that have stalled their clinical success. Finally, we briefly explore their pharmacological properties and how novel approaches could enhance their efficacy while minimising treatment-related side effects.

Beyond thyroid dysfunction: the systemic impact of iodine excess

As an essential micronutrient, iodine plays a crucial role in several physiological systems, particularly in the production of thyroid hormone. While deficiency is widely recognized, the consequences of iodine excess (IE) are less studied. IE, which may be caused by iodine-rich diets, supplements, iodinated contrast media and salt iodization, has been implicated in a range of adverse outcomes on thyroid and systemic health. Examples include autoimmune thyroid diseases like Graves' disease and Hashimoto's thyroiditis, driven by immune cell polarization and gut microbiota alterations. Furthermore, excessive iodine intake is associated with increased risks of cardiovascular diseases, including hypertension and atherosclerosis, due to oxidative stress, inflammation, and endothelial dysfunction. It contributes to the development of thyroid cancer, particularly papillary thyroid cancer, through genetic mutations such as BRAF mutations and enhanced cancer cell proliferation. Excess iodine intake has been implicated to have neurotoxic effects, significantly impairing learning and memory, negatively impacting neonatal brain development, and potentially contributing to the progression of neurodegenerative conditions. It also has a potential role in renal dysfunction in vulnerable populations, due to overload from povidone-iodine in sterile equipment. This mini-review aims to collate the adverse effects of IE, beyond its effect on thyroid health, through investigation of the cardiovascular, nervous, and renal systems. Through our consolidation of the current literature, we hope to raise awareness and contribute to the understanding of the multifaceted impact of excessive iodine intake.

TNF-α disrupts the malate-aspartate shuttle, driving metabolic rewiring in iPSC-derived enteric neural lineages from Parkinson's Disease patients

Gastrointestinal (GI) dysfunction emerges years before motor symptoms in Parkinson's disease (PD), implicating the enteric nervous system (ENS) in early disease progression. However, the mechanisms linking the PD hallmark protein, α-synuclein (α-syn), to ENS dysfunction - and whether these mechanisms are influenced by inflammation - remains elusive. Using iPSC-derived enteric neural lineages from patients with α-syn triplications, we reveal that TNF-α increases mitochondrial-α-syn interactions, disrupts the malate-aspartate shuttle, and forces a metabolic shift toward glutamine oxidation. These alterations drive mitochondrial dysfunction, characterizing metabolic impairment under cytokine stress. Interestingly, targeting glutamate metabolism with Chicago Sky Blue 6B restores mitochondrial function, reversing TNF-α-driven metabolic disruption. Our findings position the ENS as a central player in PD pathogenesis, establishing a direct link between cytokines, α-syn accumulation, metabolic stress and mitochondrial dysfunction. By uncovering a previously unrecognized metabolic vulnerability in the ENS, we highlight its potential as a therapeutic target for early PD intervention.

Identification and validation of autophagy-related genes in sepsis based on bioinformatics studies

We identified 14 key genes associated with mitochondrial autophagy in sepsis through differential analysis of the dataset and then analysed the identified genes for functional enrichment. The analysis of key genes and deeper analysis of key genes by molecular typing, Weighted Gene Correlation Network Analysis (WGCNA) and ceRNA were also carried out. We have also validated these key genes with clinical data. Finally, sepsis diagnostic models are constructed by combining key genes with machine learning methods. In addition, we discuss the importance of the immune system in sepsis and its relationship with signature genes, which opens up new directions for studying the role of the immune system in sepsis. Overall, our study adds new ideas to the diagnosis and treatment of sepsis.

Serum Biomarkers in Patent Ductus Arteriosus in Preterm Infants: A Narrative Review

Background: Patent ductus arteriosus (PDA) in preterm infants presents a significant challenge in neonatal care, marked by ongoing debates about its definition, diagnosis, treatment options, and effects on patient outcomes. Plasma biomarkers assess mediators involved in PDA closure and hemodynamic responses, assisting in identifying newborns at higher risk of developing potentially serious neonatal conditions. The purpose of this review was to investigate the relationship between PDA and various plasma biomarkers used to evaluate and diagnose ductal patency during perinatal life, as outlined in the relevant literature. Methods: We conducted an electronic search of the National Library of Medicine (MEDLINE)/PubMed and Web of Science for relevant studies published up to December 2024, including prospective, retrospective, cohort, and cross-sectional studies, as well as reviews and meta-analyses. The keywords used in the search included "preterm infant", "persistent ductus arteriosus", "patent ductus arteriosus", "PDA", "neonatal biomarkers", "cardiac biomarkers", and "vasoactive biomarkers". Results: Out of the 813 identified articles, 85 were included in our review of cardiac biomarkers: Natriuretic peptides (NPs), Cardiac troponin T (cTnT), vasoactive biomarkers (Mid-regional pro-adrenomedullin (MR-proADM), Endothelin-1 (ET-1), Copeptin, and Isoprostanes (IPs)), and inflammatory biomarkers (Interleukin-6 (IL-6), IL-8, IL-10, Growth Differentiation Factor 15 (GDF-15), Monocyte Chemoattractant Protein-1 (MCP-1/CCL2), Macrophage Inflammatory Protein-1α (MIP-1α/CCL3)) in relation to PDA. Conclusions: Even if research shows a strong correlation between specific biomarkers and echocardiographic parameters in patients with PDA, clinical judgment must take these evaluations into account, particularly when determining whether to treat a PDA. Future research should focus on investigating new biomarkers associated with the underlying mechanisms of perinatal ductus arteriosus dynamics in preterm infants.

GLP-1 receptor agonists-another promising therapy for Alport syndrome?

Alport syndrome (AS) is a progressive monogenic glomerular kidney disease characterised by kidney function decline, hearing loss, and ocular abnormalities, often leading to early-onset kidney failure (KF). While current therapies, such as renin-angiotensin system inhibitors (RASi), offer some benefits, many patients still experience KF at a young age, highlighting the need for additional treatment options. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have emerged as promising agents with demonstrated cardiovascular and nephroprotective effects in type 2 diabetes (T2D) and chronic kidney disease (CKD) patients. Evidence from several major clinical trials has shown that GLP-1 RAs can reduce cardiovascular events and slow CKD progression by reducing albuminuria. Their potential mechanisms of action include anti-inflammatory, anti-fibrotic, and antioxidative effects, making them particularly relevant for the treatment of AS, where inflammation and fibrosis play crucial roles in disease progression. This review explores the therapeutic potential of GLP-1 RAs in AS, summarising pre-clinical and clinical data and elucidating the pathways through which GLP-1 RAs might offer renoprotective benefits. We advocate for further research into their application in AS and recommend the inclusion of AS patients in future clinical trials to better understand their impact on disease progression and patient outcomes.

THE EFFECT OF CATECHOLAMINE VERSUS NONCATECHOLAMINE VASOPRESSORS ON RENAL FUNCTION AND RECOVERY IN VASODILATORY SHOCK: A SYSTEMATIC REVIEW OF PRECLINICAL AND CLINICAL STUDIES

ABSTRACT

Background: Acute kidney injury (AKI) is a common complication of vasodilatory shock. AKI is associated with an increased risk of death, prolonged hospital stays, and subsequent transition to chronic kidney disease. Catecholamines have historically been used as the first-line vasopressors for vasodilatory shock; however, they may adversely affect renal function and recovery. Objectives: To compare the effects of catecholamine and noncatecholamine vasopressors on AKI risk and recovery in preclinical and clinical studies of vasodilatory shock. Methods: MEDLINE, Embase, and Cochrane Central Register of Controlled Trials were systematically searched to identify studies reporting renal outcomes associated with catecholamine (norepinephrine, epinephrine, metaraminol, phenylephrine, dopamine) and noncatecholamine vasopressors (vasopressin, angiotensin II), in preclinical models or adult cohorts of vasodilatory shock. Two independent reviewers screened studies and extracted data using a prespecified form for qualitative synthesis and risk of bias assessment. Results: Of 3,504 citations, 90 studies were eligible for inclusion: 41 preclinical studies, 17 nonrandomized clinical studies, 28 randomized clinical studies, and 4 post-hoc analyses. Risk of bias was generally low in preclinical studies and low to moderate in clinical studies. In preclinical studies, catecholamine vasopressors exacerbated medullary hypoxia and intrarenal inflammation compared to noncatecholamine vasopressors. In clinical studies, catecholamines were associated with higher serum creatinine, lower urine output, and increased requirements for renal replacement therapy compared to noncatecholamine vasopressors. In patients on high-dose catecholamines, adjunctive angiotensin II was associated with improved renal replacement therapy liberation. Conclusion: Preclinical and clinical studies suggest that noncatecholamine vasopressors may confer renal benefits compared to catecholamine vasopressors. These hypothesis-generating observations suggest the need for comparative studies focused on renal outcomes. Systematic Review Registration : PROSPERO 2024 CRD42024527773.

Therapeutic effect of bosentan on 2, 4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis mouse model

Eczematous or atopic dermatitis (AD) is a chronic autoinflammatory skin disorder distinguished by severe itching, scratching, and erosion. Bosentan is an endothelin receptor antagonist with improved immunomodulatory and anti-inflammatory actions. This study aimed to assess the efficiency of topical bosentan in alleviating a 2, 4-dinitrochlorobenzene (DNCB)-induced mouse model of AD. 50 Swiss albino mice were haphazardly grouped into 5 teams of 10 each. The first week of the experiment involved DNCB sensitization on back skin mice, preceding a four-week DNCB challenge to induce AD-like skin inflammation. The control group gets no treatment. The induction group administered DNCB only. Starting two hours after the second sensitization, the vehicle group received topical vehicle solution, the bosentan group received 5% bosentan ointment, and the tacrolimus group received 0.1% tacrolimus ointment once daily for a period of four weeks. Topical bosentan markedly mitigated DNCB-aggravated AD-like skin lesions, as displayed by decreased total dermatitis scores and lowering the upregulated counts of total leukocytes, neutrophils, lymphocytes, monocytes, and eosinophils. Additionally, bosentan dramatically alleviated interleukin (IL)-4 and IL-13 immunohistochemistry scores, as well as IL-1β, IL-6, IL-17, TNFα, and IFN-γ epidermal levels. In conclusion, Bosentan treatment also significantly diminished levels of immunoglobulin E (IgE) and oxidative biomarker malondialdehyde (MDA) and histopathology scores, notably epidermal thickness and inflammation. Bosentan mitigates the severity of DNCB-induced AD-like skin inflammation, possibly owing to its potent anti-inflammatory and immunomodulatory properties.

The Possible effect of Bosentan on the methotrexate-induced salivary gland changes in male rats: histological and Immunohistochemical study

Methotrexate (MTX) is an antimetabolite drug utilized for managing a variety of cancers and autoinflammatory conditions. MTX may trigger detrimental effects in mout, h tissues, including salivary gland impairment. Bosentan (BOS), a drug that blocks endothelin receptors, has strengthened antioxidant, anti-inflammatory, and anti-apoptotic properties. The study aimed to estimate the protective effect of BOS on MTX-exacerbated salivary changes in Wistar Albino rats. Thirty male rats were arbitrarily sorted into three groups of ten animals each. The control group received a normal saline for 18 days. The MTX (induction) group received MTX (25 mg/kg) intraperitoneally on the 7th day of the experiment once daily for 6 consecutive days. The MTX + BOS group received BOS (50 mg/kg) orally once a day for 18 days: 6 days before induction, 6 days 2-h after induction, and 6 days post-induction. Animals were euthanized on day 19, and salivary gland tissues were dissected for biochemical, histopathological, and immunohistochemical analyses. BOS dramatically improved MTX-aggravated biochemical and histopathological abnormalities, as evidenced by diminished Bax, caspase 3, TNF-α, IL-1β, MDA, and MPO levels, increased SOD, GSH, and GPX levels, and reduced degenerative changes in the granular convolute tubule, mucous acini, and striate duct. BOS further substantially upregulated MTX-induced decline of the Ki-67 and Bcl-2, as indicated by immunohistochemistry scoring methods. The anti-oxidative, ant-inflammatory, and antiapoptotic properties of BOS are a promising strategy for ameliorating the toxic effect of MTX on submandibular glandular tissues.

Integrated proteomic and metabolomic analysis reveals the potential therapeutic mechanism of Quanduzhong capsule in rats with spontaneous hypertension and knee osteoarthritis

ETHNOPHARMACOLOGICAL RELEVANCE

Quanduzhong capsule (QDZ), derived from Eucommia ulmoides Oliv., has been traditionally used in Chinese medicine for its beneficial effects on musculoskeletal health. Its clinical application has extended to conditions such as spontaneous hypertension combined with knee osteoarthritis (SKOA). However, the specific mechanisms by which QDZ alleviates symptoms and improves outcomes in this complex condition remain to be fully elucidated.

AIM OF THE STUDY

This study aims to evaluate the therapeutic potential of QDZ in treating SKOA. By performing serum proteomics and metabolomics, we seek to explore the related biological pathways and elucidate the mechanisms underlying QDZ's effects on SKOA.

MATERIALS AND METHODS

Serum samples from control, spontaneous hypertension (SHR), SKOA, and SKOA treated with QDZ groups were analyzed using data-independent acquisition-based proteomics to identify differentially expressed proteins. Serum levels of angiotensin II, norepinephrine, endothelin-1, classical pro-inflammatory factors such as macrophage colony-stimulating factor, tumor necrosis factor-alpha, and interleukin-1 beta were measured. Additionally, serum metabolomics was performed to examine the changes in metabolite profiles. Correlation analysis was conducted to link changed proteins and metabolites with key pathways affected by QDZ.

RESULTS

Proteomics analysis revealed significant alterations in serum protein expression between control, SHR, and SKOA groups, with changes in pathways related to immune regulation and vascular function. KEGG enrichment analysis highlighted pathways such as endocytosis, synaptic vesicle cycling, and immune responses were enriched in SKOA group compared with control group. QDZ treatment significantly modulated above pathways and reduced inflammatory and cardiovascular markers which were upregulated in SKOA group. Metabolomics analysis showed that QDZ reversed SKOA-induced changes in amino acid and organic acid metabolism, affecting pathways including valine, leucine, and isoleucine metabolism, as well as the TCA cycle. Correlation analysis revealed significant relationships between key proteins and metabolites, underscoring the integrated role of immune and metabolic pathways in QDZ's effects.

CONCLUSIONS

Our results indicate QDZ has a significant therapeutic potential for SKOA by modulating both protein and metabolite profiles associated with inflammation, vascular dysfunction, and metabolic imbalance. Our findings provide insights into the mechanisms through which QDZ exerts its effects and support its use as a promising treatment for SKOA. This study highlights the impact of QDZ on proteomic and metabolomic alterations, offering a basis for its broader application in treating SKOA.

Transcriptional Responses of In Vitro Blood-Brain Barrier Models to Shear Stress

Endothelial cells throughout the body sense blood flow, eliciting transcriptional and phenotypic responses. The brain endothelium, known as the blood-brain barrier (BBB), possesses unique barrier and transport properties, which are in part regulated by blood flow. We utilized RNA sequencing to analyze the transcriptome of primary cultured rat brain microvascular endothelial cells (BMECs), as well as three human induced pluripotent stem cell-derived models. We compared the transcriptional responses of these cells to either low (0.5 dyne/cm2) or high (12 dyne/cm2) shear stresses, and subsequent analyses identified genes and pathways that were influenced by shear including key BBB-associated genes (SLC2A1, LSR, PLVAP) and canonical endothelial shear-stress-response transcription factors (KLF2, KLF4). In addition, our analysis suggests that shear alone is insufficient to rescue the de-differentiation caused by in vitro primary BMEC culture. Overall, these datasets and analyses provide new insights into the influence of shear on BBB models that will aid in model selection and guide further model development.

Molecular Mechanisms of Vascular Tone in Exercising Pediatric Populations: A Comprehensive Overview on Endothelial, Antioxidative, Metabolic and Lipoprotein Signaling Molecules

Vasoactive molecules are central regulators of vascular tone, angiogenesis and inflammation. Key molecular agents include nitric oxide (NO), endothelin-1 (ET-1), prostacyclin, free triiodothyronine (fT3), leptin, low-density lipoprotein (LDL), high-density lipoprotein (HDL), superoxide dismutase (SOD), and glutathione peroxidase (GPX). Dysregulation of these compounds can lead to endothelial dysfunction, an early predictor of atherosclerosis and cardiovascular diseases (CVD). Maintaining endothelial health is thus essential for vascular homeostasis and cardiovascular risk prevention. Regular exercise serves as a vital protective measure against CVD and the risk of cardiovascular conditions. However, young athletes often significantly exceed recommended levels of training load, engaging in highly intensive training that leads to substantial physiological adaptations. Despite this, research on the impact of exercise on vasoactive substances in children and adolescents, particularly young athletes, is limited and inconsistent. Most studies focus on those with pre-existing conditions, like obesity or diabetes mellitus. Existing findings suggest exercise may favorably affect vascular biomarkers in youth, but methodological variations hinder consistent conclusions. This literature review examines 68 studies on the effects of exercise on vascular molecules in children and adolescents, young athletes, and children and adolescents with pre-existing conditions, offering deeper insights into how exercise may influence vascular health at the molecular level.

The Crucial Role of the Blood-Brain Barrier in Neurodegenerative Diseases: Mechanisms of Disruption and Therapeutic Implications

The blood-brain barrier (BBB) is a crucial structure that maintains brain homeostasis by regulating the entry of molecules and cells from the bloodstream into the central nervous system (CNS). Neurodegenerative diseases such as Alzheimer's and Parkinson's disease, as well as ischemic stroke, compromise the integrity of the BBB. This leads to increased permeability and the infiltration of harmful substances, thereby accelerating neurodegeneration. In this review, we explore the mechanisms underlying BBB disruption, including oxidative stress, neuroinflammation, vascular dysfunction, and the loss of tight junction integrity, in patients with neurodegenerative diseases. We discuss how BBB breakdown contributes to neuroinflammation, neurotoxicity, and the abnormal accumulation of pathological proteins, all of which exacerbate neuronal damage and facilitate disease progression. Furthermore, we discuss potential therapeutic strategies aimed at preserving or restoring BBB function, such as anti-inflammatory treatments, antioxidant therapies, and approaches to enhance tight junction integrity. Given the central role of the BBB in neurodegeneration, maintaining its integrity represents a promising therapeutic approach to slow or prevent the progression of neurodegenerative diseases.

Reversal of inflammatory reprogramming by vasodilator agents in pulmonary hypertension

Background

Pulmonary arterial hypertension (PAH) is a deadly disease without effective non-invasive diagnostic and prognostic testing. It remains unclear whether vasodilators reverse inflammatory activation, a part of PAH pathogenesis. Single-cell profiling of inflammatory cells in blood could clarify these PAH mechanisms.

Methods

We evaluated a University of Pittsburgh Medical Center cohort consisting of idiopathic PAH (iPAH) and systemic sclerosis-associated PAH (sscPAH) patients and non-PAH controls. We performed single-cell RNA sequencing of peripheral blood mononuclear cells (PBMCs) from controls (n=3) and from PAH patients (iPAH and sscPAH) naïve to treatment (n=4), PAH patients 3 months after phosphodiesterase-5 inhibitor (PDE5i) treatment (n=7) and PAH patients 3 months after PDE5i+macitentan treatment (n=6). We compared the transcriptomes of five PBMC subtypes from iPAH and sscPAH to observe their serial responses to treatments. Furthermore, we utilised network analysis to illuminate the altered connectivity of biological networks in this complex disease.

Results

We defined differential gene expression and perturbed network connectivity in PBMCs of PAH patients following treatment with PDE5i or PDE5i+macitentan. Importantly, we identified significant reversal of inflammatory transcripts and pathways in the combined PAH patient cohort after vasodilator therapy in every PBMC type assessed. The "glucagon signalling in metabolic regulation" pathway in monocytes was reversed after vasodilator therapy via two independent analysis modalities.

Conclusion

Via a systems-biology approach, we define inflammatory reprogramming in the blood of PAH patients and the anti-inflammatory activity of vasodilators. Such findings establish diagnostic and prognostic blood-based tools for tracking inflammatory progression of PAH and response to therapy.

Enhanced vasoconstriction in sickle cell disease is dependent on ETA receptor activation

Sickle cell disease (SCD) carries a significant risk for poor vascular health and vascular dysfunction. High levels of vascular reactive oxygen species (ROS) as well as elevated plasma endothelin-1 (ET-1), a potent vasoconstrictor with actions via the ETA receptor, are both common phenotypes in SCD. Alpha-1 adrenergic receptor activation is a major mediator of stress-induced vasoconstriction. However, the mechanism of the SCD enhanced vasoconstrictive response is unknown. We hypothesized that SCD induces enhanced alpha-1 adrenergic mediated vasoconstriction through the ET-1/ETA receptor pathway in arterial tissues. Utilizing humanized SCD (HbSS) and genetic control (HbAA) mice, alpha-1a, but not alpha-1b or alpha-1d, receptor expression was significantly greater in aortic tissue from HbSS mice compared to HbAA mice. Significantly enhanced vasoconstriction in aortic and carotid arterial segments were observed from HbSS mice compared with HbAA mice. Treatment with ambrisentan, a selective ETA receptor antagonist, and a ROS scavenger normalized the aortic vasoconstrictive response in HbSS mice. In a randomized translational study, patients with SCD were treated with placebo or ambrisentan for 3 months, with the treatment group showing an increase in the percent brachial arterial diameter. Taken together, these data suggest that the ETA receptor pathway interaction with the adrenergic receptor pathway contributes to enhanced aortic vasoconstriction in SCD. Findings indicate the potential of ETA antagonism as a therapeutic avenue for improving vascular health in SCD.

Comprehensive Insights into Mechanisms for Ventricular Remodeling in Right Heart Failure

Ventricular remodeling in right heart failure is a complex pathological process involving interactions between multiple mechanisms. Overactivation of the neuro-hormonal pathways, activation of the oxidative stress response, expression of cytokines, apoptosis of cardiomyocytes, and alterations of the extracellular matrix (ECM) are among the major mechanisms involved in the development of ventricular remodeling in right heart failure. These mechanisms are involved in ventricular remodeling, such as myocardial hypertrophy and fibrosis, leading to the deterioration of myocardial systolic and diastolic function. A deeper understanding of these mechanisms can help develop more effective therapeutic strategies in patients with right heart failure (RHF) to improve patient survival and quality of life. Despite the importance of ventricular remodeling in RHF, there are a limited number of studies in this field. This article explores in-depth historical and current information about the specific mechanisms in ventricular remodeling in RHF, providing a theoretical rationale for recognizing its importance in health and disease.

A tale of two endothelins: the rise and fall of the corpus luteum

Endothelins are small 21 amino acid peptides that interact with G-protein-coupled receptors. They are highly conserved across species and play important roles in vascular biology as well as in disease development and progression. Endothelins, mainly endothelin-1 and endothelin-2, are intricately involved in ovarian function and metabolism. These two peptides differ only in two amino acids but are encoded by different genes, which suggests an independent regulation and a cell-specific mode of expression. This review aims to comprehensively discuss the distinct regulation and roles of endothelin-1 and endothelin-2 regarding corpus luteum function throughout its life span.

Mechanisms underlying the roles of leukocytes in the progression of cystic fibrosis

Recent advances in cystic fibrosis (CF) treatments have led to improved survival, with life expectancy for Australians living with CF at 57yo. As life expectancy improves, long-term cardiovascular disease risk factors (as for the general population) will become an issue in these patients. We hypothesized that increased leukocyte expression of vasoconstriction and pro-fibrotic mediators may contribute to CF severity in adults with CF. We recruited 13 adult and 24 pediatric healthy controls, and 53 adults and 9 children living with CF. Leukocyte expression/release of endothelin-1 (ET1) and members of the TGF-β/Smad signaling were measured by multifluorescence quantitative confocal microscopy, Western blotting, ELISA, and real-time quantitative polymerase chain reaction. The association between plasma ET1 levels and lung function was assessed. Leukocytes from adults living with CF expressed higher ET1 levels (p = 0.0033), and TGF-β (p = 0.0031); the phosphorylation ratio increased for Smad2/3 (p = 0.0136) but decreased for Smad1/5/8 (p = 0.0007), vs. control subjects. Plasma ET1 levels were significantly increased in adults with CF with FEV1<50% (p = 0.002) vs. controls, and adults with CF with normal lung function. The release of ET1 in adult plasma inversely correlated with CF severity (-0.609, p = 0.046). Our data indicates that upregulated ET1 and TGF-β/Smad signaling in leukocytes may contribute to CF severity, highlighting the need for further investigations into their impact on the clinical outcomes of people living with CF.

Recurrent endothelin-1 mediated vascular insult leads to cognitive impairment protected by trophic factor pleiotrophin

Vascular dementia (VaD) is a complex neurodegenerative condition, with cerebral small vessel dysfunctions as the central role in its pathogenesis. Given the lack of suitable animal models to study the disease pathogenesis, we developed a mouse model to closely emulate the clinical scenarios of recurrent transient ischemic attacks (TIAs) leading to VaD using vasoconstricting peptide Endothelin-1(ET-1). We observed that administration of ET-1 led to blood-brain barrier (BBB) disruption and detrimental changes in its components, such as endothelial cells and pericytes, along with neuronal loss and synaptic dysfunction, resulting in irreversible memory loss. Further, in our pursuit of understanding potential interventions, we co-administered pleiotrophin (PTN) alongside ET-1 injections. PTN exhibited remarkable efficacy in preserving vital components of the BBB, including endothelial cells and pericytes, thereby restoring BBB integrity, preventing neuronal loss, and enhancing memory function. Our findings give a valuable framework for understanding the detrimental effects of multiple TIAs on brain health and provide a useful animal model to explore VaD's underlying mechanisms further and pave the way for promising therapies.

Combined Analysis of Second- and Third-Generation Transcriptome Sequencing for Gene Characteristics and Identification of Key Splicing Variants in Wound Healing of Ganxi Goat Skin

Ganxi goat is a local breed of goat unique to Jiangxi Province, China, named for its primary distribution in the Ganxi region. Ganxi goats are primarily raised through grazing, showing good adaptation to the local humid and hot climate, strong disease resistance, and occupying an important position in the local livestock industry. The skin, as the main barrier of the body, plays an indispensable role in resisting the invasion of external pathogenic factors and has received increasing attention in the medical and scientific fields. In this study, Ganxi goat skin was used as the research subject. Full-length transcriptome sequencing of Ganxi goat skin was performed using PacBio third-generation sequencing technology to supplement and improve the annotation information of the Ganxi goat genome. A combined analysis of second- and third-generation transcriptome sequencing was used to analyze the splicing variant events of hub genes (CDC20, MMP2, TIMP1, and EDN1) and the expression changes in each splicing variant in skin samples on day 0 and day 5 after surgical wounding. The regulatory role of related hub gene splicing variants in wound healing was analyzed. A total of 926,667 full-length non-chimeric sequences were obtained, optimizing the annotation information of 3794 genomic gene loci and identifying 2834 new genes, 256 new LncRNAs, 12,283 alternative splicing events, 549 genes with polyadenylation, and 112 fusion genes. Three splicing variant forms were identified in both the CDC20 and EDN1 genes, seven in MMP2, and two in TIMP1. The expression levels of most splicing variants showed significant changes in the skin samples on days 0 and 5 after wounding, potentially participating in the regulation of wound healing. This study provides fundamental data for the annotation of the goat genome and offers a reference for studying the regulatory mechanisms of wound healing.

A critical examination of human data for the biological activity of phenolic acids and their phase-2 conjugates derived from dietary (poly)phenols, phenylalanine, tyrosine and catecholamines

Free or conjugated aromatic/phenolic acids arise from the diet, endogenous metabolism of catecholamines (adrenaline, noradrenaline, dopamine), protein (phenylalanine, tyrosine), pharmaceuticals (aspirin, metaprolol) plus gut microbiota metabolism of dietary (poly)phenols and undigested protein. Quantitative data obtained with authentic calibrants for 112 aromatic/phenolic acids including phase-2 conjugates in human plasma, urine, ileal fluid, feces and tissues have been collated and mean/median values compared with in vitro bioactivity data in cultured cells. Ca 30% of publications report bioactivity at ≤1 μmol/L. With support from clinical studies, it appears that the greatest benefit might be produced in vascular tissues by C6-C3 metabolites, including some of gut microbiota origin and some phase-2 conjugates, 15 of which are 3',4'-disubstituted with multiple sources including caffeic acid and hesperetin, plus one unsubstituted and two mono-substituted examples which can originate from protein. There is an unexamined potential for synergy. Free-living and washout plasma data are scarce. Some metabolites have been overlooked, notably phenyl-lactic, phenyl-hydracrylic and phenyl-propanoic acids, especially those from amino acids plus glycine, hydroxy-glycine and glutamine conjugates. Phenolic acids and conjugates from multiple sources exhibit biological activities, some of which are likely relevant in vivo and link to biomarkers of health. Further targeted studies are justified.

Sexual dimorphism of hypothalamic serotonin release during systemic inflammation: Role of endothelin-1

The hypothalamus receives serotonergic projections from the raphe nucleus in a sex-specific manner. During systemic inflammation, hypothalamic levels of serotonin (5-hydroxytryptamine [5-HT]) decrease in male rats. The present study evaluated the involvement of endothelin-1 (ET-1) in the febrile response, hypolocomotion, and changes in hypothalamic 5-HT levels during systemic inflammation in male and female rats. An intraperitoneal injection of lipopolysaccharide (LPS) induced a febrile response and hypolocomotion in both male and female rats. However, although LPS reduced hypothalamic levels of 5-HT and its metabolite 5-hydroxyindol acetic acid (5-HIAA) in male rats, it increased these levels in female rats. An intracerebroventricular injection of the endothelin-B receptor antagonist BQ788 significantly reduced LPS-induced fever and hypolocomotion and changes in hypothalamic 5-HT and 5-HIAA levels in both male and female rats. The i.c.v. administration of ET-1 induced a significant fever and hypolocomotion, but reduced the hypothalamic levels of 5-HT and 5-HIAA in both males and females. These results suggest an important sexual dimorphism during systemic inflammation regarding the release of 5-HT in the hypothalamus. Moreover, ET-1 arises as an important mediator involved in the changes in hypothalamic 5-HT levels in both male and female rats.

A review of novel endothelin antagonists and overview of non-steroidal mineralocorticoid antagonists for treating resistant hypertension: An update

Several agents are emerging from five different novel classes of antihypertensive medications. We will focus on endothelin antagonists and non-steroidal mineralocorticoid receptor antagonists. While several agents exist in this later class, only a couple have demonstrated superior efficacy in resistant hypertension management. Endothelin receptor antagonists are effective therapy for primary and resistant hypertension, but they are not widely used. This is due to side effects demonstrated in large clinical trials, specifically increased peripheral edema and worsening heart failure in some cases, as well as the availability of many alternative agents to manage blood pressure effectively. However, the relationship between endothelin and its close ties to hypertension is evolving. Recent pre-clinical work explores new applications of more selective endothelin receptor antagonists. They suggest that specific subtypes of hypertension may benefit more from endothelin receptor blockade than simply those with primary hypertension. We review this topic and other related data. Lastly, we also provide a brief overview of non-steroidal mineralocorticoid receptor antagonists as some in the class show promise as antihypertensive agents.

Endothelial Cells Increase Mesenchymal Stem Cell Differentiation in Scaffold-Free 3D Vascular Tissue

In this study, we present a versatile, scaffold-free approach to create ring-shaped engineered vascular tissue segments using human mesenchymal stem cell-derived smooth muscle cells (hMSC-SMCs) and endothelial cells (ECs). We hypothesized that incorporation of ECs would increase hMSC-SMC differentiation without compromising tissue ring strength or fusion to form tissue tubes. Undifferentiated hMSCs and ECs were co-seeded into custom ring-shaped agarose wells using four different concentrations of ECs: 0%, 10%, 20%, and 30%. Co-seeded EC and hMSC rings were cultured in SMC differentiation medium for a total of 22 days. Tissue rings were then harvested for histology, Western blotting, wire myography, and uniaxial tensile testing to examine their structural and functional properties. Differentiated hMSC tissue rings comprising 20% and 30% ECs exhibited significantly greater SMC contractile protein expression, endothelin-1 (ET-1)-meditated contraction, and force at failure compared with the 0% EC rings. On average, the 0%, 10%, 20%, and 30% EC rings exhibited a contractile force of 0.745 ± 0.117, 0.830 ± 0.358, 1.31 ± 0.353, and 1.67 ± 0.351 mN (mean ± standard deviation [SD]) in response to ET-1, respectively. Additionally, the mean maximum force at failure for the 0%, 10%, 20%, and 30% EC rings was 88.5 ± 36. , 121 ± 59.1, 147 ± 43.1, and 206 ±  0.8 mN (mean ± SD), respectively. Based on these results, 30% EC rings were fused together to form tissue-engineered blood vessels (TEBVs) and compared with 0% EC TEBV controls. The addition of 30% ECs in TEBVs did not affect ring fusion but did result in significantly greater SMC protein expression (calponin and smoothelin). In summary, co-seeding hMSCs with ECs to form tissue rings resulted in greater contraction, strength, and hMSC-SMC differentiation compared with hMSCs alone and indicates a method to create a functional 3D human vascular cell coculture model.

Capillary regression leads to sustained local hypoperfusion by inducing constriction of upstream transitional vessels

In the brain, a microvascular sensory web coordinates oxygen delivery to regions of neuronal activity. This involves a dense network of capillaries that send conductive signals upstream to feeding arterioles to promote vasodilation and blood flow. Although this process is critical to the metabolic supply of healthy brain tissue, it may also be a point of vulnerability in disease. Deterioration of capillary networks is a feature of many neurological disorders and injuries and how this web is engaged during vascular damage remains unknown. We performed in vivo two-photon microscopy on young adult mural cell reporter mice and induced focal capillary injuries using precise two-photon laser irradiation of single capillaries. We found that ~59% of the injuries resulted in regression of the capillary segment 7 to 14 d following injury, and the remaining repaired to reestablish blood flow within 7 d. Injuries that resulted in capillary regression induced sustained vasoconstriction in the upstream arteriole-capillary transition (ACT) zone at least 21 days postinjury in both awake and anesthetized mice. The degree of vasomotor dynamics was chronically attenuated in the ACT zone consequently reducing blood flow in the ACT zone and in secondary, uninjured downstream capillaries. These findings demonstrate how focal capillary injury and regression can impair the microvascular sensory web and contribute to cerebral hypoperfusion.

A Randomized, Controlled Comparison of NCX 470, a Nitric Oxide-Donating Bimatoprost, and Latanoprost in Subjects with Open-Angle Glaucoma or Ocular Hypertension: The MONT BLANC Study

PURPOSE

To compare intraocular pressure (IOP)-lowering efficacy and safety of NCX 470, a nitric oxide (NO)-donating bimatoprost, to latanoprost in subjects with open-angle glaucoma (OAG) or ocular hypertension (OHT).

DESIGN

Prospective, phase 3, randomized, adaptive dose-selection, double-masked, parallel-group trial.

METHODS

691 subjects with OAG or OHT and unmedicated IOP ≥26 mmHg at 8AM, ≥24 mmHg at 10AM, and ≥22 mmHg at 4PM in the study eye were randomized to NCX 470 0.065%, NCX 470 0.1%, or latanoprost 0.005%. An interim analysis was performed to select the final dose of NCX 470. We evaluated noninferiority of NCX 470 versus latanoprost, based on IOP reduction from baseline at 8AM and 4PM at 2 weeks, 6 weeks, and 3 months.

RESULTS

661 subjects were analyzed; IOP was significantly reduced at all on-treatment time points, with reductions ranging from 8.0 to 9.7 mmHg (P < .0001 at each time point) in the NCX 470 0.1% group. Mean IOP reductions were greater with NCX 470 0.1% than latanoprost 0.005% at all 6 time points and significantly greater (P < .05) at 4 of the 6 time points. The most common adverse event was conjunctival/ocular hyperemia.

CONCLUSION

The NO-donating prostaglandin analogue NCX 470 0.1% was well-tolerated and lowered IOP more than latanoprost in subjects with OAG or OHT at all 6 time points. With a dual mechanism of action that enhances both uveoscleral and trabecular outflow, NCX 470 could become an important first-line therapy for IOP reduction in glaucoma.

Sitting knee-flexion angle does not influence endothelial-dependent vasodilation in laboratory or free-living conditions

INTRODUCTION

Single bouts of prolonged bent-legged sitting attenuate popliteal endothelial-dependent vasodilation (as assessed via flow-mediated dilation [FMD]), which is partially attributed to arterial 'kinking'. However, the impact of knee-flexion angle on sitting-induced popliteal FMD is unknown. The objective of this study was to perform separate laboratory and free-living studies to test the hypotheses that: (1) popliteal FMD impairments would be graded between knee flexions at 90° (bent-legged sitting) > 45° > 0° (straight-legged sitting) following a 3-hour bout of sitting; and (2) more habitual time spent bent-legged sitting (< 45°) would be associated with lower FMD.

METHODS

The laboratory study included eight young, healthy adults (24 ± 2 years; four women) who underwent two sitting bouts over 2 days with one leg positioned at a knee-flexion angle of 0° or 90° and the opposite leg at 45° knee flexion. Popliteal FMD was assessed at pre- and postsitting timepoints.

RESULTS

Sitting-induced reductions in FMD were similar between all knee-flexion angles (all, p > 0.674). The free-living study included 35 young, healthy adults (23 ± 3 years; 16 women) who wore three activPAL monitors (torso, thigh, shin) to determine detailed sedentary postures. Time spent sedentary (624 ± 127 min/day), straight-legged sitting (112 ± 98 min/day), and bent-legged sitting (442 ± 106 min/day) were not related to relative FMD (5.3 ± 1.8%; all, p > 0.240).

CONCLUSION

These findings suggest that knee-flexion angle-mediated arterial 'kinking' during sitting is not a major contributor toward sitting-induced popliteal endothelial-dependent vasodilatory dysfunction.

Evaluating the impact of type 2 diabetes mellitus on pulmonary vascular function and the development of pulmonary fibrosis

The increasing prevalence of type 2 diabetes mellitus (T2DM) is a significant worldwide health concern caused by sedentary lifestyles and unhealthy diets. Beyond glycemic control, T2DM impacts multiple organ systems, leading to various complications. While traditionally associated with cardiovascular and microvascular complications, emerging evidence indicates significant effects on pulmonary health. Pulmonary vascular dysfunction and fibrosis, characterized by alterations in vascular tone and excessive extracellular matrix deposition, are increasingly recognized in individuals with T2DM. The onset of T2DM is often preceded by prediabetes, an intermediate hyperglycemic state that is associated with increased diabetes and cardiovascular disease risk. This review explores the relationship between T2DM, pulmonary vascular dysfunction and pulmonary fibrosis, with a focus on potential links with prediabetes. Pulmonary vascular function, including the roles of nitric oxide (NO), prostacyclin (PGI2), endothelin-1 (ET-1), thromboxane A2 (TxA2) and thrombospondin-1 (THBS1), is discussed in the context of T2DM and prediabetes. Mechanisms linking T2DM to pulmonary fibrosis, such as oxidative stress, dysregulated fibrotic signaling, and chronic inflammation, are explained. The impact of prediabetes on pulmonary health, including endothelial dysfunction, oxidative stress, and dysregulated vasoactive mediators, is highlighted. Early detection and intervention during the prediabetic stage may reduce respiratory complications associated with T2DM, emphasizing the importance of management strategies targeting blood glucose regulation and vascular health. More research that looks into the mechanisms underlying pulmonary complications in T2DM and prediabetes is needed.

Single-cell transcriptome analysis of cavernous tissues reveals the key roles of pericytes in diabetic erectile dysfunction

Erectile dysfunction (ED) affects a significant proportion of men aged 40-70 and is caused by cavernous tissue dysfunction. Presently, the most common treatment for ED is phosphodiesterase 5 inhibitors; however, this is less effective in patients with severe vascular disease such as diabetic ED. Therefore, there is a need for development of new treatment, which requires a better understanding of the cavernous microenvironment and cell-cell communications under diabetic condition. Pericytes are vital in penile erection; however, their dysfunction due to diabetes remains unclear. In this study, we performed single-cell RNA sequencing to understand the cellular landscape of cavernous tissues and cell type-specific transcriptional changes in diabetic ED. We found a decreased expression of genes associated with collagen or extracellular matrix organization and angiogenesis in diabetic fibroblasts, chondrocytes, myofibroblasts, valve-related lymphatic endothelial cells, and pericytes. Moreover, the newly identified pericyte-specific marker, Limb Bud-Heart (Lbh), in mouse and human cavernous tissues, clearly distinguishing pericytes from smooth muscle cells. Cell-cell interaction analysis revealed that pericytes are involved in angiogenesis, adhesion, and migration by communicating with other cell types in the corpus cavernosum; however, these interactions were highly reduced under diabetic conditions. Lbh expression is low in diabetic pericytes, and overexpression of LBH prevents erectile function by regulating neurovascular regeneration. Furthermore, the LBH-interacting proteins (Crystallin Alpha B and Vimentin) were identified in mouse cavernous pericytes through LC-MS/MS analysis, indicating that their interactions were critical for maintaining pericyte function. Thus, our study reveals novel targets and insights into the pathogenesis of ED in patients with diabetes.

Spontaneous coronary artery dissection and fibromuscular dysplasia: insights into recent developments

Spontaneous coronary artery dissection (SCAD), an uncommon cause of acute coronary syndrome, continues to be a poorly understood disease predominantly affecting females. It is characterized by an abrupt separation in the coronary arterial wall due to intramural bleeding. Fibromuscular dysplasia (FMD) is a non-atherosclerotic arteriopathy manifesting in medium and small-sized arteries. It is a concomitant disease found among SCAD patients. In some studies, FMD prevalence in SCAD patients ranges between 25%-86%, which can be explained through varying screening techniques or modalities. The potential association has been elucidated in some studies; notably, not only has a genetic link been recently delineated between SCAD and FMD, but there is data to suggest that FMD not only can predispose to SCAD but can also be a potential predictor of its recurrence. However, a clear-cut correlation between the two has still not been established due to conflicting reports in the literature. To further dive into its pathology, it is crucial to highlight the importance of systematic screening in SCAD in order to identify associated risk factors and to be used as a method of FMD detection in such patients. Together, the two pathologies pose unique challenges in understanding its pathophysiology, diagnosis and management, as there is no clear evidence of a definitive treatment plan for patients with SCAD and FMD. A potentially beneficial modality of management is physical exercise, which is currently understudied in the long-term approach to treatment for patients with concomitant SCAD and FMD. Limited research in this field brings disadvantages to the understanding of the association between these two diseases, in order to give rise to better management recommendations. This mini-review aims to highlight the recent developments in the association between SCAD and FMD, its potential genetic association and some insights in screening, diagnosis, and management.

Innovative Treatments to Counteract Endothelial Dysfunction in Chronic Kidney Disease Patients

In chronic kidney disease (CKD) patients, several risk factors contribute to the development of endothelial dysfunction (ED), which can be described as an alteration in the cell structure or in the function of the endothelium. Among the well-known CKD-related risk factors capable of altering the production of endothelium-derived relaxing factors, we include asymmetric dimethylarginine increase, reduced dimethylarginine dimethylamine hydrolase enzyme activity, low-grade chronic systemic inflammation, hyperhomocysteinemia, oxidative stress, insulin resistance, alteration of calcium phosphorus metabolism, and early aging. In this review, we also examined the most important techniques useful for studying ED in humans, which are divided into indirect and direct methods. The direct study of coronary endothelial function is considered the gold standard technique to evaluate if ED is present. In addition to the discussion of the main pharmacological treatments useful to counteract ED in CKD patients (namely sodium-glucose cotransporter 2 inhibitors and mineralocorticoid receptor antagonist), we elucidate innovative non-pharmacological treatments that are successful in accompanying the pharmacological ones. Among them, the most important are the consumption of extra virgin olive oil with high intake of minor polar compounds, adherence to a plant-dominant, low-protein diet (LPD), an adaptive physical activity program and, finally, ketoanalogue administration in combination with the LPD or the very low-protein diet.

Endothelial cell dynamics in sepsis-induced acute lung injury and acute respiratory distress syndrome: pathogenesis and therapeutic implications

Sepsis, a prevalent critical condition in clinics, continues to be the leading cause of death from infections and a global healthcare issue. Among the organs susceptible to the harmful effects of sepsis, the lungs are notably the most frequently affected. Consequently, patients with sepsis are predisposed to developing acute lung injury (ALI), and in severe cases, acute respiratory distress syndrome (ARDS). Nevertheless, the precise mechanisms associated with the onset of ALI/ARDS remain elusive. In recent years, there has been a growing emphasis on the role of endothelial cells (ECs), a cell type integral to lung barrier function, and their interactions with various stromal cells in sepsis-induced ALI/ARDS. In this comprehensive review, we summarize the involvement of endothelial cells and their intricate interplay with immune cells and stromal cells, including pulmonary epithelial cells and fibroblasts, in the pathogenesis of sepsis-induced ALI/ARDS, with particular emphasis placed on discussing the several pivotal pathways implicated in this process. Furthermore, we discuss the potential therapeutic interventions for modulating the functions of endothelial cells, their interactions with immune cells and stromal cells, and relevant pathways associated with ALI/ARDS to present a potential therapeutic strategy for managing sepsis and sepsis-induced ALI/ARDS.

Normal-Tension Glaucoma and Potential Clinical Links to Alzheimer's Disease

Glaucoma is a group of optic neuropathies and the world's leading cause of irreversible blindness. Normal-tension glaucoma (NTG) is a subtype of glaucoma that is characterized by a typical pattern of peripheral retinal loss, in which the patient's intraocular pressure (IOP) is considered within the normal range (<21 mmHg). Currently, the only targetable risk factor for glaucoma is lowering IOP, and patients with NTG continue to experience visual field loss after IOP-lowering treatments. This demonstrates the need for a better understanding of the pathogenesis of NTG and underlying mechanisms leading to neurodegeneration. Recent studies have found significant connections between NTG and cerebral manifestations, suggesting NTG as a neurodegenerative disease beyond the eye. Gaining a better understanding of NTG can potentially provide new Alzheimer's Disease diagnostics capabilities. This review identifies the epidemiology, current biomarkers, altered fluid dynamics, and cerebral and ocular manifestations to examine connections and discrepancies between the mechanisms of NTG and Alzheimer's Disease.

Efficacy and safety of zibotentan and dapagliflozin in patients with chronic kidney disease: study design and baseline characteristics of the ZENITH-CKD trial

BACKGROUND

Sodium-glucose co-transporter 2 inhibitors (SGLT2is) are part of the standard of care for patients with chronic kidney disease (CKD), both with and without type 2 diabetes. Endothelin A (ETA) receptor antagonists have also been shown to slow progression of CKD. Differing mechanisms of action of SGLT2 and ETA receptor antagonists may enhance efficacy. We outline a study to evaluate the effect of combination zibotentan/dapagliflozin versus dapagliflozin alone on albuminuria and estimated glomerular filtration rate (eGFR).

METHODS

We are conducting a double-blind, active-controlled, Phase 2b study to evaluate the efficacy and safety of ETA receptor antagonist zibotentan and SGLT2i dapagliflozin in a planned 415 adults with CKD (Zibotentan and Dapagliflozin for the Treatment of CKD; ZENITH-CKD). Participants are being randomized (1:2:2) to zibotentan 0.25 mg/dapagliflozin 10 mg once daily (QD), zibotentan 1.5 mg/dapagliflozin 10 mg QD and dapagliflozin 10 mg QD alone, for 12 weeks followed by a 2-week off-treatment wash-out period. The primary endpoint is the change in log-transformed urinary albumin-to-creatinine ratio (UACR) from baseline to Week 12. Other outcomes include change in blood pressure from baseline to Week 12 and change in eGFR the study. The incidence of adverse events will be monitored. Study protocol-defined events of special interest include changes in fluid-related measures (weight gain or B-type natriuretic peptide).

RESULTS

A total of 447 patients were randomized and received treatment in placebo/dapagliflozin (n = 177), zibotentan 0.25 mg/dapagliflozin (n = 91) and zibotentan 1.5 mg/dapagliflozin (n =  179). The mean age was 62.8 years, 30.9% were female and 68.2% were white. At baseline, the mean eGFR of the enrolled population was 46.7 mL/min/1.73 m2 and the geometric mean UACR was 538.3 mg/g.

CONCLUSION

This study evaluates the UACR-lowering efficacy and safety of zibotentan with dapagliflozin as a potential new treatment for CKD. The study will provide information about an effective and safe zibotentan dose to be further investigated in a Phase 3 clinical outcome trial.

CLINICAL TRIAL REGISTRATION NUMBER

NCT04724837.

Cardiac cell senescence: molecular mechanisms, key proteins and therapeutic targets

Cardiac aging, particularly cardiac cell senescence, is a natural process that occurs as we age. Heart function gradually declines in old age, leading to continuous heart failure, even in people without a prior history of heart disease. To address this issue and improve cardiac cell function, it is crucial to investigate the molecular mechanisms underlying cardiac senescence. This review summarizes the main mechanisms and key proteins involved in cardiac cell senescence. This review further discusses the molecular modulators of cellular senescence in aging hearts. Furthermore, the discussion will encompass comprehensive descriptions of the key drugs, modes of action and potential targets for intervention in cardiac senescence. By offering a fresh perspective and comprehensive insights into the molecular mechanisms of cardiac senescence, this review seeks to provide a fresh perspective and important theoretical foundations for the development of drugs targeting this condition.

Role of Helicobacter pylori Infection in Pathogenesis, Evolution, and Complication of Atherosclerotic Plaque

The therapeutic management of atherosclerosis focuses almost exclusively on the reduction of plasma cholesterol levels. An important role in the genesis and evolution of atherosclerosis is played by chronic inflammation in promoting thrombosis phenomena after atheroma rupture. This review aims to take stock of the knowledge so far accumulated on the role of endemic HP infection in atherosclerosis. The studies produced so far have demonstrated a causal relationship between Helicobacter pylori (HP) and CVD. In a previous study, we demonstrated in HP-positive patients that thrombin and plasma fragment 1 + 2 production was proportionally related to tumor necrosis factor-alpha levels and that eradication of the infection resulted in a reduction of inflammation. At the end of our review, we can state that HP slightly affects the risk of CVD, particularly if the infection is associated with cytotoxic damage, and HP screening could have a clinically significant role in patients with a high risk of CVD. Considering the high prevalence of HP infection, an infection screening could be of great clinical utility in patients at high risk of CVD.

Deciphering the immunological interactions: targeting preeclampsia with Hydroxychloroquine's biological mechanisms

Preeclampsia (PE) is a complex pregnancy-related disorder characterized by hypertension, followed by organ dysfunction and uteroplacental abnormalities. It remains a major cause of maternal and neonatal morbidity and mortality worldwide. Although the pathophysiology of PE has not been fully elucidated, a two-stage model has been proposed. In this model, a poorly perfused placenta releases various factors into the maternal circulation during the first stage, including pro-inflammatory cytokines, anti-angiogenic factors, and damage-associated molecular patterns into the maternal circulation. In the second stage, these factors lead to a systemic vascular dysfunction with consecutive clinical maternal and/or fetal manifestations. Despite advances in feto-maternal management, effective prophylactic and therapeutic options for PE are still lacking. Since termination of pregnancy is the only curative therapy, regardless of gestational age, new treatment/prophylactic options are urgently needed. Hydroxychloroquine (HCQ) is mainly used to treat malaria as well as certain autoimmune conditions such as systemic lupus and rheumatoid arthritis. The exact mechanism of action of HCQ is not fully understood, but several mechanisms of action have been proposed based on its pharmacological properties. Interestingly, many of them might counteract the proposed processes involved in the development of PE. Therefore, based on a literature review, we aimed to investigate the interrelated biological processes of HCQ and PE and to identify potential molecular targets in these processes.

Inflammation of some visceral sensory systems and autonomic dysfunction in cardiovascular disease

The sensitization and hypertonicity of visceral afferents are highly relevant to the development and progression of cardiovascular and respiratory disease states. In this review, we described the evidence that the inflammatory process regulates visceral afferent sensitivity and tonicity, affecting the control of the cardiovascular and respiratory system. Some inflammatory mediators like nitric oxide, angiotensin II, endothelin-1, and arginine vasopressin may inhibit baroreceptor afferents and contribute to the baroreflex impairment observed in cardiovascular diseases. Cytokines may act directly on peripheral afferent terminals that transmit information to the central nervous system (CNS). TLR-4 receptors, which recognize lipopolysaccharide, were identified in the nodose and petrosal ganglion and have been implicated in disrupting the blood-brain barrier, which can potentiate the inflammatory process. For example, cytokines may cross the blood-brain barrier to access the CNS. Additionally, pro-inflammatory cytokines such as IL-1β, IL-6, TNF-α and some of their receptors have been identified in the nodose ganglion and carotid body. These pro-inflammatory cytokines also sensitize the dorsal root ganglion or are released in the nucleus of the solitary tract. In cardiovascular disease, pro-inflammatory mediators increase in the brain, heart, vessels, and plasma and may act locally or systemically to activate/sensitize afferent nervous terminals. Recent evidence demonstrated that the carotid body chemoreceptor cells might sense systemic pro-inflammatory molecules, supporting the novel proposal that the carotid body is part of the afferent pathway in the central anti-inflammatory reflexes. The exact mechanisms of how pro-inflammatory mediators affects visceral afferent signals and contribute to the pathophysiology of cardiovascular diseases awaits future research.

Respiratory tract infection: an unfamiliar risk factor in high-altitude pulmonary edema

The dramatic changes in physiology at high altitude (HA) as a result of the characteristic hypobaric hypoxia condition can modify innate and adaptive defense mechanisms of the body. As a consequence, few sojourners visiting HA with mild or asymptomatic infection may have an enhanced susceptibility to high-altitude pulmonary edema (HAPE), an acute but severe altitude sickness. It develops upon rapid ascent to altitudes above 2500 m, in otherwise healthy individuals. Though HAPE has been studied extensively, an elaborate exploration of the HA disease burden and the potential risk factors associated with its manifestation are poorly described. The present review discusses respiratory tract infection (RTI) as an unfamiliar but important risk factor in enhancing HAPE susceptibility in sojourners for two primary reasons. First, the symptoms of RTI s resemble those of HAPE. Secondly, the imbalanced pathways contributing to vascular dysfunction in HAPE also participate in the pathogenesis of the infectious processes. These pathways have a crucial role in shaping host response against viral and bacterial infections and may further worsen the clinical outcomes at HA. Respiratory tract pathogenic agents, if screened in HAPE patients, can help in ascertaining their role in disease risk and also point toward their association with the disease severity. The microbial screenings and identifications of pathogens with diseases are the foundation for describing potential molecular mechanisms underlying host response to the microbial challenge. The prior knowledge of such infections may predict the manifestation of disease etiology and provide better therapeutic options.

The impact of lipopolysaccharide on cerebrovascular function and cognition resulting from obesity-induced gut dysbiosis

Obesity is a worldwide epidemic coinciding with a concomitant increase in the incidence of neurodegenerative diseases, particularly dementia. Obesity is characterised by increased adiposity, chronic low-grade systemic inflammation, and oxidative stress, which promote endothelial dysfunction. Endothelial dysfunction reduces cerebrovascular function leading to reduced cerebral blood flow and, eventually, cognitive decline, thus predisposing to a neurodegenerative disease. Obesity is also characterised by gut dysbiosis and a subsequent increase in the lipopolysaccharide which increasingly activates toll-like receptor 4 (TLR4) and further promotes chronic low-grade systemic inflammation. This also disrupts the crosstalk within the gut-brain axis, thus influencing the functions of the central nervous system, including cognition. However, the mechanisms by which obesity-related increases in oxidative stress, inflammation and endothelial dysfunction are driven by, or associated with, increased systemic lipopolysaccharide leading to reduced cerebrovascular function and cognition, beyond normal ageing, have not been elucidated. Hence, this review examines how increased concentrations of lipopolysaccharide and the subsequent increased TLR4 activation observed in obesity exacerbate the development of obesity-induced reductions in cerebrovascular function and cognition.

Contributing Factors to Endothelial Dysfunction in Individuals with Spinal Cord Injuries

Background

Patients with spinal cord injuries (SCIs) are at a greater risk for the development of cardiovascular diseases (CVDs) than able-bodied individuals due to the high risk of endothelial dysfunction.

Summary

For instance, patients with SCIs lose autonomic control of the heart and vasculature, which results in severe fluctuations in blood pressure. These oscillations between hypotension and hypertension have been shown to damage blood vessel endothelial cells and may contribute to the development of atherosclerosis. Furthermore, the loss of skeletal muscle control results in skeletal muscle atrophy and inward remodeling of the conduit arteries. It has been shown that blood vessels in the legs are chronically exposed to high shear, while the aorta experiences chronically low shear. These alterations to shear forces may adversely impact endothelial vasodilatory capacity and promote inflammatory signaling and leukocyte adherence. Additionally, microvascular endothelial vasodilatory capacity is impaired in patients with an SCI, and this may precede changes in conduit artery endothelial function. Finally, due to immobility and a loss of skeletal muscle mass, patients with SCIs have a higher risk of metabolic disorders, inflammation, and oxidative stress.

Key Messages

Collectively, these factors may impair endothelium-dependent vasodilatory capacity, promote leukocyte adhesion and infiltration, promote the peroxidation of lipids, and ultimately support the development of atherosclerosis. Therefore, future interventions to prevent CVDs in patients with SCIs should focus on the management of endothelial health to prevent endothelial dysfunction and atherosclerosis.

Identification of Important Genes Associated with the Development of Atherosclerosis

Atherosclerosis is one of the most important medical problems due to its prevalence and significant contribution to the structure of temporary and permanent disability and mortality. Atherosclerosis is a complex chain of events occurring in the vascular wall over many years. Disorders of lipid metabolism, inflammation, and impaired hemodynamics are important mechanisms of atherogenesis. A growing body of evidence strengthens the understanding of the role of genetic and epigenetic factors in individual predisposition and development of atherosclerosis and its clinical outcomes. In addition, hemodynamic changes, lipid metabolism abnormalities, and inflammation are closely related and have many overlapping links in regulation. A better study of these mechanisms may improve the quality of diagnosis and management of such patients.