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Abstract Background The associations between deprivation and illness trajectory after hospitalisation for coronavirus disease-19 (COVID-19) are uncertain. Methods A prospective, multicentre cohort study was conducted on post-COVID-19 patients, enrolled either in-hospital or shortly post-discharge. Two evaluations were carried out: an initial assessment and a follow-up at 28–60 days post-discharge. The study encompassed research blood tests, patient-reported outcome measures, and multisystem imaging (including chest computed tomography (CT) with pulmonary and coronary angiography, cardiovascular and renal magnetic resonance imaging). Primary and secondary outcomes were analysed in relation to socioeconomic status, using the Scottish Index of Multiple Deprivation (SIMD). The EQ-5D-5L, Brief Illness Perception Questionnaire (BIPQ), Patient Health Questionnaire-4 (PHQ-4) for Anxiety and Depression, and the Duke Activity Status Index (DASI) were used to assess health status. Results Of the 252 enrolled patients (mean age 55.0 ± 12.0 years; 40% female; 23% with diabetes), deprivation status was linked with increased BMI and diabetes prevalence. 186 (74%) returned for the follow-up. Within this group, findings indicated associations between deprivation and lung abnormalities (p = 0.0085), coronary artery disease (p = 0.0128), and renal inflammation (p = 0.0421). Furthermore, patients with higher deprivation exhibited worse scores in health-related quality of life (EQ-5D-5L, p = 0.0084), illness perception (BIPQ, p = 0.0004), anxiety and depression levels (PHQ-4, p = 0.0038), and diminished physical activity (DASI, p = 0.002). At the 3-month mark, those with greater deprivation showed a higher frequency of referrals to secondary care due to ongoing COVID-19 symptoms (p = 0.0438). However, clinical outcomes were not influenced by deprivation. Conclusions In a post-hospital COVID-19 population, socioeconomic deprivation was associated with impaired health status and secondary care episodes. Deprivation influences illness trajectory after COVID-19.

Abstract COVID-19, caused by SARS-CoV-2, is a respiratory disease associated with inflammation and endotheliitis. Mechanisms underling inflammatory processes are unclear, but angiotensin converting enzyme 2 (ACE2), the receptor which binds the spike protein of SARS-CoV-2 may be important. Here we investigated whether spike protein binding to ACE2 induces inflammation in endothelial cells and determined the role of ACE2 in this process. Human endothelial cells were exposed to SARS-CoV-2 spike protein, S1 subunit (rS1p) and pro-inflammatory signaling and inflammatory mediators assessed. ACE2 was modulated pharmacologically and by siRNA. Endothelial cells were also exposed to SARS-CoV-2. rSP1 increased production of IL-6, MCP-1, ICAM-1 and PAI-1, and induced NFkB activation via ACE2 in endothelial cells. rS1p increased microparticle formation, a functional marker of endothelial injury. ACE2 interacting proteins involved in inflammation and RNA biology were identified in rS1p-treated cells. Neither ACE2 expression nor ACE2 enzymatic function were affected by rSP1. Endothelial cells exposed to SARS-CoV-2 virus did not exhibit viral replication. We demonstrate that rSP1 induces endothelial inflammation via ACE2 through processes that are independent of ACE2 enzymatic activity and viral replication. We define a novel role for ACE2 in COVID-19- associated endotheliitis.

Chronic hyperglycemia induces intrarenal oxidative stress due to the excessive production of reactive oxygen species (ROS), leading to a cascade of events that contribute to the development and progression of diabetic kidney disease (DKD). NOX5, a pro-oxidant NADPH oxidase isoform, has been identified as a significant contributor to renal ROS in humans. Elevated levels of renal ROS contribute to endothelial cell dysfunction and associated inflammation, causing increased endothelial permeability, which can disrupt the renal ecosystem, leading to progressive albuminuria and renal fibrosis in DKD. This study specifically examines the contribution of endothelial cell-specific human NOX5 expression in renal pathology in a transgenic mouse model of DKD. This study additionally compares NOX5 with the previously characterized NADPH oxidase, NOX4, in terms of their relative roles in DKD. Regardless of NOX4 pathway, this study found that endothelial cell-specific expression of NOX5 exacerbates renal injury, albuminuria and fibrosis. This is attributed to the activation of the endothelial mesenchymal transition (EMT) pathway via enhanced ROS formation and the modulation of redox-sensitive factors. These findings underscore the potential therapeutic significance of NOX5 inhibition in human DKD. The study proposes that inhibiting NOX5 could be a promising approach for mitigating the progression of DKD and strengthens the case for the development of NOX5-specific inhibitors as a potential therapeutic intervention.

Deficiency of the Mg2+-permeable channel/α-kinase TRPM7 in mice increases susceptibility to cardiovascular and renal fibrosis induced by aldosterone and salt.

Background Hypertension and vascular toxicity are major unwanted side effects of antiangiogenic drugs, such as vascular endothelial growth factor inhibitors (VEGFis), which are effective anticancer drugs but have unwanted side effects, including vascular toxicity and hypertension. Poly (ADP‐ribose) polymerase (PARP) inhibitors, used to treat ovarian and other cancers, have also been associated with elevated blood pressure. However, when patients with cancer receive both olaparib, a PARP inhibitor, and VEGFi, the risk of blood pressure elevation is reduced. Underlying molecular mechanisms are unclear, but PARP‐regulated transient receptor potential cation channel, subfamily M, member 2 (TRPM2), a redox‐sensitive calcium channel, may be important. We investigated whether PARP/TRPM2 plays a role in VEGFi‐induced vascular dysfunction and whether PARP inhibition ameliorates the vasculopathy associated with VEGF inhibition. Methods and Results Human vascular smooth muscle cells (VSMCs), human aortic endothelial cells, and wild‐type mouse mesenteric arteries were studied. Cells/arteries were exposed to axitinib (VEGFi) alone and in combination with olaparib. Reactive oxygen species production, Ca2+ influx, protein/gene analysis, PARP activity, and TRPM2 signaling were assessed in VSMCs, and nitric oxide levels were determined in endothelial cells. Vascular function was assessed by myography. Axitinib increased PARP activity in VSMCs in a reactive oxygen species‐dependent manner. Endothelial dysfunction and hypercontractile responses were ameliorated by olaparib and a TRPM2 blocker (8‐Br‐cADPR). VSMC reactive oxygen species production, Ca2+ influx, and phosphorylation of myosin light chain 20 and endothelial nitric oxide synthase (Thr495) were augmented by axitinib and attenuated by olaparib and TRPM2 inhibition. Proinflammatory markers were upregulated in axitinib‐stimulated VSMCs, which was reduced by reactive oxygen species scavengers and PARP‐TRPM2 inhibition. Human aortic endothelial cells exposed to combined olaparib and axitinib showed nitric oxide levels similar to VEGF‐stimulated cells. Conclusions Axitinib‐mediated vascular dysfunction involves PARP and TRPM2, which, when inhibited, ameliorate the injurious effects of VEGFi. Our findings define a potential mechanism whereby PARP inhibitor may attenuate vascular toxicity in VEGFi‐treated patients with cancer.

Receptor tyrosine kinases (RTKs) are a class of membrane spanning cell-surface receptors that transmit extracellular signals through the membrane to trigger diverse intracellular signaling through tyrosine kinases (TKs), and play important role in cancer development. Therapeutic approaches targeting RTKs such as vascular endothelial growth factor receptor (VEGFR), epidermal growth factor receptor (EGFR), and platelet-derived growth factor receptor (PDGFR), and TKs, such as c-Src, ABL, JAK, are widely used to treat human cancers. Despite favorable benefits in cancer treatment that prolong survival, these tyrosine kinase inhibitors (TKIs) and monoclonal antibodies targeting RTKs are also accompanied by adverse effects, including cardiovascular toxicity. Mechanisms underlying TKI-induced cardiovascular toxicity remain unclear. The transient receptor potential melastatin-subfamily member 7 (TRPM7) is a ubiquitously expressed chanzyme consisting of a membrane-based ion channel and intracellular α-kinase. TRPM7 is a cation channel that regulates transmembrane Mg2+ and Ca2+ and is involved in a variety of (patho)physiological processes in the cardiovascular system, contributing to hypertension, cardiac fibrosis, inflammation, and atrial arrhythmias. Of importance, we and others demonstrated significant cross-talk between TRPM7, RTKs, and TK signaling in different cell types including vascular smooth muscle cells (VSMCs), which might be a link between TKIs and their cardiovascular effects. In this review, we summarize the implications of RTK inhibitors (RTKIs) and TKIs in cardiovascular toxicities during anti-cancer treatment, with a focus on the potential role of TRPM7/Mg2+ as a mediator of RTKI/TKI-induced cardiovascular toxicity. We also describe the important role of TRPM7 in cancer development and cardiovascular diseases, and the interaction between TRPM7 and RTKs, providing insights for possible mechanisms underlying cardiovascular disease in cancer patients treated with RTKI/TKIs.

The current COVID-19 pandemic, caused by the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) virus, represents the largest medical challenge in decades. It has exposed unexpected cardiovascular vulnerabilities at all stages of the disease (pre-infection, acute phase, and subsequent chronic phase). The major cardiometabolic drivers identified as having epidemiologic and mechanistic associations with COVID-19 are abnormal adiposity, dysglycemia, dyslipidemia, and hypertension. Hypertension is of particular interest, because components of the renin–angiotensin system (RAS), which are critically involved in the pathophysiology of hypertension, are also implicated in COVID-19. Specifically, angiotensin-converting enzyme-2 (ACE2), a multifunctional protein of the RAS, which is part of the protective axis of the RAS, is also the receptor through which SARS-CoV-2 enters host cells, causing viral infection. Cardiovascular and cardiometabolic comorbidities not only predispose people to COVID-19, but also are complications of SARS-CoV-2 infection. In addition, increasing evidence indicates that acute kidney injury is common in COVID-19, occurs early and in temporal association with respiratory failure, and is associated with poor prognosis, especially in the presence of cardiovascular risk factors. Here, we discuss cardiovascular and kidney disease in the context of COVID-19 and provide recent advances on putative pathophysiological mechanisms linking cardiovascular disease and COVID-19, focusing on the RAS and ACE2, as well as the immune system and inflammation. We provide up-to-date information on the relationships among hypertension, diabetes, and COVID-19 and emphasize the major cardiovascular diseases associated with COVID-19. We also briefly discuss emerging cardiovascular complications associated with long COVID-19, notably postural tachycardia syndrome (POTS). Résumé: La pandémie actuelle de COVID-19 causée par le coronavirus du syndrome respiratoire aigu sévère 2 (SRAS-CoV-2) est le plus grand enjeu médical des dernières décennies. Elle a mis en évidence des vulnérabilités cardiovasculaires imprévues à tous les stades de la COVID-19 (avant l'infection, pendant la phase aiguë et pendant la phase chronique subséquente). Les principaux facteurs cardiométaboliques dont les associations épidémiologiques et mécanistiques avec la COVID-19 ont été avérées comprennent l'adiposité anormale, la dysglycémie, la dyslipidémie et l'hypertension. L'hypertension suscite un intérêt particulier, car certaines composantes du système rénine-angiotensine (SRA), dont le rôle est crucial dans la physiopathologie de l'hypertension, sont également en cause dans la COVID-19. Plus précisément, l'enzyme de conversion de l'angiotensine 2 (ECA2), une protéine multifonctionnelle du SRA faisant partie de l'axe protecteur du SRA, est également le récepteur permettant au virus SRAS-CoV-2 d'entrer dans les cellules hôtes et de provoquer une infection virale. Les affections cardiovasculaires et cardiométaboliques concomitantes ne font pas que prédisposer les personnes qui en sont atteintes à la COVID-19, elles constituent également des complications de l'infection à SRAS-CoV-2. En outre, de plus en plus de données probantes indiquent que l'atteinte rénale aiguë est fréquente en cas de COVID-19, qu'elle survient tôt et fait l'objet d'une association temporelle avec l'insuffisance respiratoire, et qu'elle est associée à un pronostic sombre, notamment en présence de facteurs de risque cardiovasculaires. Nous discutons ici des maladies cardiovasculaires et rénales dans le contexte de la COVID-19, et présentons les progrès récents sur les mécanismes physiopathologiques en cause dans le lien entre les maladies cardiovasculaires et la COVID-19 en nous attardant sur le SRA et l'ECA2, ainsi que sur le système immunitaire et l'inflammation. Nous présentons de l'information à jour sur les liens entre l'hypertension, le diabète et la COVID-19, et soulignons les principales maladies cardiovasculaires associées à la COVID-19. Nous analysons également brièvement les complications cardiovasculaires émergentes associées à la COVID-19 de longue durée, notamment le syndrome de tachycardie orthostatique posturale (STOP).

Background: Cisplatin-based chemotherapy increases the risk of cardiovascular and renal disease. Objectives: We aimed to define the time course, pathophysiology, and approaches to prevent cardiovascular disease associated with cisplatin-based chemotherapy. Methods: Two cohorts of patients with a history of testicular cancer (n = 53) were recruited. Cohort 1 consisted of 27 men undergoing treatment with: 1) surveillance; 2) 1 to 2 cycles of bleomycin, etoposide, and cisplatin (BEP) chemotherapy (low-intensity cisplatin); or 3) 3 to 4 cycles of BEP (high-intensity cisplatin). Endothelial function (percentage flow-mediated dilatation) and cardiovascular biomarkers were assessed at 6 visits over 9 months. Cohort 2 consisted of 26 men previously treated 1 to 7 years ago with surveillance or 3 to 4 cycles BEP. Vasomotor and fibrinolytic responses to bradykinin, acetylcholine, and sodium nitroprusside were evaluated using forearm venous occlusion plethysmography. Results: In cohort 1, the percentage flow-mediated dilatation decreased 24 h after the first cisplatin dose in patients managed with 3 to 4 cycles BEP (10.9 ± 0.9 vs. 16.7 ± 1.6; p < 0.01) but was unchanged from baseline thereafter. Six weeks after starting 3 to 4 cycles BEP, there were increased serum cholesterol levels (7.2 ± 0.5 mmol/l vs. 5.5 ± 0.2 mmol/l; p = 0.01), hemoglobin A1c (41.8 ± 2.0 mmol/l vs. 35.5 ± 1.2 mmol/l; p < 0.001), von Willebrand factor antigen (62.4 ± 5.4 mmol/l vs. 45.2 ± 2.8 mmol/l; p = 0.048) and cystatin C (0.91 ± 0.07 mmol/l vs. 0.65 ± 0.09 mmol/l; p < 0.01). In cohort 2, intra-arterial bradykinin, acetylcholine, and sodium nitroprusside caused dose-dependent vasodilation (p < 0.0001). Vasomotor responses, endogenous fibrinolytic factor release, and cardiovascular biomarkers were not different in patients managed with 3 to 4 cycles of BEP versus surveillance. Conclusions: Cisplatin-based chemotherapy induces acute and transient endothelial dysfunction, dyslipidemia, hyperglycemia, and nephrotoxicity in the early phases of treatment. Cardiovascular and renal protective strategies should target the early perichemotherapy period. (Clinical Characterisation of the Vascular Effects of Cis-platinum Based Chemotherapy in Patients With Testicular Cancer [VECTOR], NCT03557177; Intermediate and Long Term Vascular Effects of Cisplatin in Patients With Testicular Cancer [INTELLECT], NCT03557164)

Na+ has been suggested to accumulate in tissues, particularly skin, in a hypertonic manner and to exert local pathogenic effects. Here, we reappraise this phenomenon which is systemic in nature and reflects isotonic changes in the relative extracellular volume in tissues, e.g. subclinical oedema; as such, it occurs in human hypertension and aging.

Current research on hypertension utilizes more than fifty animal models that rely mainly on stable increases in systolic blood pressure. In experimental hypertension, grading or scoring of glomerulopathy in the majority of studies is based on a wide range of opinion-based histological changes that do not necessarily comply with lesional descriptors for glomerular injury that are well-established in clinical pathology. Here, we provide a critical appraisal of experimental hypertensive glomerulopathy with the same approach used to assess hypertensive glomerulopathy in humans. Four hypertensive models with varying pathogenesis were analyzed–chronic angiotensin II infused mice, mice expressing active human renin in the liver (TTRhRen), spontaneously hypertensive rats (SHR), and Goldblatt two-kidney one-clip rats (2K1C). Analysis of glomerulopathy utilized the same criteria applied in humans–hyalinosis, focal segmental glomerulosclerosis (FSGS), ischemic, hypertrophic and solidified glomeruli, or global glomerulosclerosis (GGS). Data from animal models were compared to human reference values. Kidneys in TTRhRen mice, SHR and the nonclipped kidneys in 2K1C rats had no sign of hyalinosis, FSGS or GGS. Glomerulopathy in these groups was limited to variations in mesangial and capillary compartment volumes, with mild increases in collagen deposition. Histopathology in angiotensin II infused mice corresponded to mesangioproliferative glomerulonephritis, but not hypertensive glomerulosclerosis. The number of nephrons was significantly reduced in TTRhRen mice and SHR, but did not correlate with severity of glomerulopathy. The most substantial human-like glomerulosclerotic lesions, including FSGS, ischemic obsolescent glomeruli and GGS, were found in the clipped kidneys of 2K1C rats. The comparison of affected kidneys to healthy control in animals produces lesion values that are numerically impressive but correspond to mild damage if compared to humans. Animal studies should be standardized by employing the criteria and classifications established in human pathology to make experimental and human data fully comparable for comprehensive analysis and model improvements.

Summary: CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy) is the most common form of genetic stroke and vascular dementia syndrome resulting from mutations in NOTCH3. To elucidate molecular mechanisms of the condition and identify drug targets, we established a patient-specific induced pluripotent stem cell (iPSC) model and demonstrated for the first time a failure of the patient iPSC-derived vascular mural cells (iPSC-MCs) in engaging and stabilizing endothelial capillary structures. The patient iPSC-MCs had reduced platelet-derived growth factor receptor β, decreased secretion of the angiogenic factor vascular endothelial growth factor (VEGF), were highly susceptible to apoptotic insults, and could induce apoptosis of adjacent endothelial cells. Supplementation of VEGF significantly rescued the capillary destabilization. Small interfering RNA knockdown of NOTCH3 in iPSC-MCs revealed a gain-of-function mechanism for the mutant NOTCH3. These disease mechanisms likely delay brain repair after stroke in CADASIL, contributing to the brain hypoperfusion and dementia in this condition, and will help to identify potential drug targets. : Wang, Kimber and colleagues established an iPSC model for the most common genetic stroke and vascular dementia syndrome CADASIL, and identified primary defects of iPSC-derived mural cells in stabilizing vascular capillary structures with reduced PDGFRβ expression and VEGF secretion. Supplementation of VEGF significantly rescued the capillary destabilization, suggesting a therapeutic target. siRNA knockdown of NOTCH3 suggests a gain-of-function mechanism. Keywords: iPSC, iPSC disease model, small vessel disease, vascular dementia, CADASIL, NOTCH3, angiogenesis, pericytes, genetic stroke, notch signaling

Dynamic contrast-enhanced MRI (DCE-MRI) is increasingly used to quantify and map the spatial distribution of blood-brain barrier (BBB) leakage in neurodegenerative disease, including cerebral small vessel disease and dementia. However, the subtle nature of leakage and resulting small signal changes make quantification challenging. While simplified one-dimensional simulations have probed the impact of noise, scanner drift, and model assumptions, the impact of spatio-temporal effects such as gross motion, k-space sampling and motion artefacts on parametric leakage maps has been overlooked. Moreover, evidence on which to base the design of imaging protocols is lacking due to practical difficulties and the lack of a reference method. To address these problems, we present an open-source computational model of the DCE-MRI acquisition process for generating four dimensional Digital Reference Objects (DROs), using a high-resolution brain atlas and incorporating realistic patient motion, extra-cerebral signals, noise and k-space sampling. Simulations using the DROs demonstrated a dominant influence of spatio-temporal effects on both the visual appearance of parameter maps and on measured tissue leakage rates. The computational model permits greater understanding of the sensitivity and limitations of subtle BBB leakage measurement and provides a non-invasive means of testing and optimising imaging protocols for future studies.

SARS-CoV-2 viral attachment and entry into host cells is mediated by a direct interaction between viral spike glycoproteins and membrane bound angiotensin-converting enzyme 2 (ACE2). The receptor binding motif (RBM), located within the S1 subunit of the spike protein, incorporates the majority of known ACE2 contact residues responsible for high affinity binding and associated virulence. Observation of existing crystal structures of the SARS-CoV-2 receptor binding domain (SRBD)–ACE2 interface, combined with peptide array screening, allowed us to define a series of linear native RBM-derived peptides that were selected as potential antiviral decoy sequences with the aim of directly binding ACE2 and attenuating viral cell entry. RBM1 (16mer): S443KVGGNYNYLYRLFRK458, RBM2A (25mer): E484GFNCYFPLQSYGFQPTNGVGYQPY508, RBM2B (20mer): F456NCYFPLQSYGFQPTNGVGY505 and RBM2A-Sc (25mer): NYGLQGSPFGYQETPYPFCNFVQYG. Data from fluorescence polarisation experiments suggested direct binding between RBM peptides and ACE2, with binding affinities ranging from the high nM to low μM range (Kd = 0.207–1.206 μM). However, the RBM peptides demonstrated only modest effects in preventing SRBD internalisation and showed no antiviral activity in a spike protein trimer neutralisation assay. The RBM peptides also failed to suppress S1-protein mediated inflammation in an endogenously expressing ACE2 human cell line. We conclude that linear native RBM-derived peptides are unable to outcompete viral spike protein for binding to ACE2 and therefore represent a suboptimal approach to inhibiting SARS-CoV-2 viral cell entry. These findings reinforce the notion that larger biologics (such as soluble ACE2, ‘miniproteins’, nanobodies and antibodies) are likely better suited as SARS-CoV-2 cell-entry inhibitors than short-sequence linear peptides.

Abstract Activation of aldosterone/mineralocorticoid receptors (MR) has been implicated in vascular dysfunction of diabetes. Underlying mechanisms are elusive. Therefore, we investigated the role of Rho kinase (ROCK) in aldosterone/MR signaling and vascular dysfunction in a model of diabetes. Diabetic obese mice (db/db) and control counterparts (db/+) were treated with MR antagonist (MRA, potassium canrenoate, 30 mg/kg/day, 4 weeks) or ROCK inhibitor, fasudil (30 mg/kg/day, 3 weeks). Plasma aldosterone was increased in db/db versus db/+. This was associated with enhanced vascular MR signaling. Norepinephrine (NE)-induced contraction was increased in arteries from db/db mice. These responses were attenuated in mice treated with canrenoate or fasudil. Db/db mice displayed hypertrophic remodeling and increased arterial stiffness, improved by MR blockade. Vascular calcium sensitivity was similar between depolarized arteries from db/+ and db/db. Vascular hypercontractility in db/db mice was associated with increased myosin light chain phosphorylation and reduced expression of PKG-1α. Vascular RhoA/ROCK signaling and expression of pro-inflammatory and pro-fibrotic markers were exaggerated in db/db mice, effects that were attenuated by MRA. Fasudil, but not MRA, improved vascular insulin sensitivity in db/db mice, evidenced by normalization of Irs1 phosphorylation. Our data identify novel pathways involving MR-RhoA/ROCK-PKG-1 that underlie vascular dysfunction and injury in diabetic mice.

The European Cooperation in Science and Technology (COST) provides an ideal framework to establish multi-disciplinary research networks. COST Action BM1203 (EU-ROS) represents a consortium of researchers from different disciplines who are dedicated to providing new insights and tools for better understanding redox biology and medicine and, in the long run, to finding new therapeutic strategies to target dysregulated redox processes in various diseases. This report highlights the major achievements of EU-ROS as well as research updates and new perspectives arising from its members. The EU-ROS consortium comprised more than 140 active members who worked together for four years on the topics briefly described below. The formation of reactive oxygen and nitrogen species (RONS) is an established hallmark of our aerobic environment and metabolism but RONS also act as messengers via redox regulation of essential cellular processes. The fact that many diseases have been found to be associated with oxidative stress established the theory of oxidative stress as a trigger of diseases that can be corrected by antioxidant therapy. However, while experimental studies support this thesis, clinical studies still generate controversial results, due to complex pathophysiology of oxidative stress in humans. For future improvement of antioxidant therapy and better understanding of redox-associated disease progression detailed knowledge on the sources and targets of RONS formation and discrimination of their detrimental or beneficial roles is required. In order to advance this important area of biology and medicine, highly synergistic approaches combining a variety of diverse and contrasting disciplines are needed.

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) can be used to examine the distribution of an intravenous contrast agent within the brain. Computational methods have been devised to analyse the contrast uptake/washout over time as reflections of cerebrovascular dysfunction. However, there have been few direct comparisons of their relative strengths and weaknesses. In this paper, we compare five semiquantitative methods comprising the slope and area under the enhancement-time curve, the slope and area under the concentration-time curve ( S l o p e C o n and A U C C o n ), and changes in the power spectrum over time. We studied them in cerebrospinal fluid, normal tissues, stroke lesions, and white matter hyperintensities (WMH) using DCE-MRI scans from a cohort of patients with small vessel disease (SVD) who presented mild stroke. The total SVD score was associated with A U C C o n in WMH ( p < 0.05 ), but not with the other four methods. In WMH, we found higher A U C C o n was associated with younger age ( p < 0.001 ) and fewer WMH ( p < 0.001 ), whereas S l o p e C o n increased with younger age ( p > 0.05 ) and WMH burden ( p > 0.05 ). Our results show the potential of different measures extracted from concentration-time curves extracted from the same DCE examination to demonstrate cerebrovascular dysfunction better than those extracted from enhancement-time curves.

Background NADPH Oxidase 5 (Nox5) is a calcium‐sensitive superoxide‐generating Nox. It is present in lower forms and higher mammals, but not in rodents. Nox5 is expressed in vascular cells, but the functional significance remains elusive. Given that contraction is controlled by calcium and reactive oxygen species, both associated with Nox5, we questioned the role of Nox5 in pro‐contractile signaling and vascular function. Methods and Results Transgenic mice expressing human Nox5 in a vascular smooth muscle cell–specific manner (Nox5 mice) and Rhodnius prolixus, an arthropod model that expresses Nox5 endogenoulsy, were studied. Reactive oxygen species generation was increased systemically and in the vasculature and heart in Nox5 mice. In Nox5‐expressing mice, agonist‐induced vasoconstriction was exaggerated and endothelium‐dependent vasorelaxation was impaired. Vascular structural and mechanical properties were not influenced by Nox5. Vascular contractile responses in Nox5 mice were normalized by N‐acetylcysteine and inhibitors of calcium channels, calmodulin, and endoplasmic reticulum ryanodine receptors, but not by GKT137831 (Nox1/4 inhibitor). At the cellular level, vascular changes in Nox5 mice were associated with increased vascular smooth muscle cell [Ca2+]i, increased reactive oxygen species and nitrotyrosine levels, and hyperphosphorylation of pro‐contractile signaling molecules MLC20 (myosin light chain 20) and MYPT1 (myosin phosphatase target subunit 1). Blood pressure was similar in wild‐type and Nox5 mice. Nox5 did not amplify angiotensin II effects. In R. prolixus, gastrointestinal smooth muscle contraction was blunted by Nox5 silencing, but not by VAS2870 (Nox1/2/4 inhibitor). Conclusions Nox5 is a pro‐contractile Nox isoform important in redox‐sensitive contraction. This involves calcium‐calmodulin and endoplasmic reticulum–regulated mechanisms. Our findings define a novel function for vascular Nox5, linking calcium and reactive oxygen species to the pro‐contractile molecular machinery in vascular smooth muscle cells.

Background and aim: Perivascular adipose tissue (PVAT) positively regulates vascular function through production of factors such as adiponectin but this effect is attenuated in obesity. The enzyme AMP-activated protein kinase (AMPK) is present in PVAT and is implicated in mediating the vascular effects of adiponectin. In this study, we investigated the effect of an obesogenic high fat diet (HFD) on aortic PVAT and whether any changes involved AMPK.Methods: Wild type Sv129 (WT) and AMPKα1 knockout (KO) mice aged 8 weeks were fed normal diet (ND) or HFD (42% kcal fat) for 12 weeks. Adiponectin production by PVAT was assessed by ELISA and AMPK expression studied using immunoblotting. Macrophages in PVAT were identified using immunohistochemistry and markers of M1 and M2 macrophage subtypes evaluated using real time-qPCR. Vascular responses were measured in endothelium-denuded aortic rings with or without attached PVAT. Carotid wire injury was performed and PVAT inflammation studied 7 days later.Key results: Aortic PVAT from KO and WT mice was morphologically indistinct but KO PVAT had more infiltrating macrophages. HFD caused an increased infiltration of macrophages in WT mice with increased expression of the M1 macrophage markers Nos2 and Il1b and the M2 marker Chil3. In WT mice, HFD reduced the anticontractile effect of PVAT as well as reducing adiponectin secretion and AMPK phosphorylation. PVAT from KO mice on ND had significantly reduced adiponectin secretion and no anticontractile effect and feeding HFD did not alter this. Wire injury induced macrophage infiltration of PVAT but did not cause further infiltration in KO mice.Conclusions: High-fat diet causes an inflammatory infiltrate, reduced AMPK phosphorylation and attenuates the anticontractile effect of murine aortic PVAT. Mice lacking AMPKα1 phenocopy many of the changes in wild-type aortic PVAT after HFD, suggesting that AMPK may protect the vessel against deleterious changes in response to HFD.

The transient receptor potential melastatin-subfamily member 7 (TRPM7) is a ubiquitously expressed chanzyme that possesses an ion channel permeable to the divalent cations Mg2+, Ca2+, and Zn2+, and an α-kinase that phosphorylates downstream substrates. TRPM7 and its homologue TRPM6 have been implicated in a variety of cellular functions and is critically associated with intracellular signaling, including receptor tyrosine kinase (RTK)-mediated pathways. Emerging evidence indicates that growth factors, such as EGF and VEGF, signal through their RTKs, which regulate activity of TRPM6 and TRPM7. TRPM6 is primarily an epithelial-associated channel, while TRPM7 is more ubiquitous. In this review we focus on TRPM7 and its association with growth factors, RTKs, and downstream kinase signaling. We also highlight how interplay between TRPM7, Mg2+ and signaling kinases influences cell function in physiological and pathological conditions, such as cancer and preeclampsia.

Background. Changes in cardiopulmonary reserve and biomarkers related to wall stress, inflammation, and oxidative stress concomitantly with the evaluation of peripheral arterial blood flow have not been investigated in patients with heart failure with preserved ejection fraction (HFpEF) compared with healthy subjects (CTL). Methods and Results. Eighteen HFpEF patients and 14 CTL were recruited. Plasma levels of inflammatory and oxidative stress biomarkers were measured at rest. Brain natriuretic peptide (BNP) was measured at rest and peak exercise. Cardiopulmonary reserve was assessed using an exercise protocol with gas exchange analyses. Peripheral arterial blood flow was determined by strain gauge plethysmography. Peak VO2 (12.0±0.4 versus 19.1±1.1 mL/min/kg, P