Vascular function: a key player in hypertension

Blood pressure variability as predictor of cancer therapy-related cardiovascular toxicity in patients with Multiple Myeloma

Blood pressure (BP) variability (BPV) is an independent predictor of cardiovascular (CV) events. The role of BPV in defining risk of cancer therapy-related cardiovascular toxicity (CTR-CVT) is currently unknown. The aims of this study were: (i) to evaluate BPV in a population of patients with Multiple Myeloma, undergoing proteasome inhibitors therapy; (ii) to assess the predictive value of BPV for CTR-CVT; (iii) to analyze clusters of subjects based on BPV. One hundred twenty-four patients underwent a baseline evaluation, including Ambulatory Blood Pressure Monitoring (ABPM), PWV, and Echocardiography. BPV was assessed through ABPM-based standard deviation (SD), weighted standard deviation (wSD), coefficient of variation (CoV), average real variability (ARV), and variability independent of the mean (VIM). Individuals who developed CTR-CVT had a higher baseline BPV. Furthermore, night-time BPV was associated with CTR-CVT, independently of age, smoking, BP, diabetes, dyslipidemia, and kidney function (night-time systolic CoV: adjusted OR 1.09 [1.01-1.21]; night-time systolic VIM: adjusted OR 1.18 [1.01-1.39]). Cut-offs for these BPV parameters were identified as predictors of CTR-CVT occurrence: 10.5 for night-time systolic CoV; 7.8 and 6.4 for systolic and diastolic night-time VIM. Clustering analysis identified subgroups of subjects characterized by the highest BPV, who had a greater prevalence of events, but no differences in other CV risk determinants. Short-term BPV is an independent predictor of CTR-CVT. BPV may enhance the precision of risk stratification in cancer patients, enabling identification of individuals at higher risk who would not be recognized, if traditional prognostic indicators were the sole applied criteria. On the left panel in the figure, the distribution of blood pressure variability (BPV) in the population according to cancer therapy-related cardiovascular toxicity occurrence; in the central panel, association of blood pressure variability with events and cutoffs values; in the right panel, clustering analysis results based on BPV levels. Histogram and radar plot represent events and BPV indexes distribution in the three clusters, respectively. ARV, average real variability; BPV, Blood Pressure Variability; CTR-CVT, cancer therapy-related cardiovascular toxicity; CoV, coefficient of variation; DBP, Diastolic blood pressure; SBP, Systolic blood pressure; SD, standard deviation; VIM, variability independent of the mean; wSD, weighted standard deviation.

A vascular endothelial cell, neuron, and microglia tri-culture model to study hypertension-related depression

Hypertension-related Depression (HD) is a complex mental disorder that exerts a significant negative impact on patients' quality of life. Previous studies have demonstrated that damages to vascular endothelial and hippocampus are the primary pathological features in HD rats. Under hypertensive conditions, inflammatory cytokines in peripheral blood vessels can induce central nervous system inflammation through penetration of a damaged blood-brain barrier, peripheral immune cells, and neural pathways, damaging the brain and triggering HD. Therefore, interactions between vascular endothelial cells, neurons, and glial cells are critical for the understanding of HD. However, in vivo animal models are often limited by the complexity of intrinsic systems, high inter-individual variability, and stringent ethical regulations. A reliable model that could be easily manipulated is needed for investigating the mechanisms involved in communication between vascular endothelial cells, neurons, and glial cells in HD. We therefore aimed to create a composite tri-culture model consisting of rat aortic endothelial cells (RAECs), neurons, and microglia to study HD. First, RAECs were stimulated with lipopolysaccharide to mimic endothelial injury under hypertensive conditions. Vascular endothelial function and inflammatory levels were assessed using fluorescent probes and enzyme-linked immunosorbent assays. RAECs treated with 1 μg/ml LPS for 24 h had reduced levels of nitric oxide, increased levels of endothelin-1 and inflammatory mediators. These findings are consistent with the endothelial dysfunction and inflammatory responses observed in spontaneously hypertensive rats, which suggests that the lipopolysaccharide-induced RAECs model effectively mimics key pathological features of hypertension-related endothelial injury. Subsequently, the supernatants from lipopolysaccharide-induced RAECs were combined with 200 μM corticosterone and transferred to neuron-microglia co-cultures to simulate damages to hippocampal neuron under HD conditions. To evaluate the features of cells, neuronal viability was measured by CCK-8 and live-dead assays. Nissl staining was used to assess neuronal Nissl bodies, while the levels of inflammatory factors and monoamine neurotransmitters in the culture supernatants were evaluated by enzyme-linked immunosorbent assays. Reactive oxygen species in neurons were visualized by a fluorescent probe, apoptosis was detected using TUNEL assays, and immunofluorescence was used to assess microglial phenotypes and the levels of TLR4 and NF-κB. It was found that neurons in the tri-culture model had reduced viability, higher levels of apoptosis, fewer Nissl bodies, increased inflammation, and reduced levels of monoamine neurotransmitters. Additionally, the number of M1 microglia was increased, along with elevated levels of TLR4 and NF-κB proteins. These findings were similar to damages of hippocampal neuron, abnormal levels of monoamine neurotransmitters, microglia polarization, and hippocampal inflammatory response observed in the HD rat model. In conclusion, our findings indicate that the tri-culture model can effectively simulate the pathological characteristics of HD, especially in vascular endothelial damage, neuroinflammation, monoamine neurotransmitters disorders. Therefore, the tri-culture model would provides a reliable and invaluable experimental tool for further research on the pathogenesis and treatment of HD.

Regulation of Vascular Injury and Repair by P21-Activated Kinase 1 and P21-Activated Kinase 2: Therapeutic Potential and Challenges

The PAK (p21-activated kinases) family is a class of intracellular signal transduction protein kinases that regulate various cellular functions, mainly through their interactions with small GTP enzymes. PAK1 and PAK2 in the PAK kinase family are key signal transduction molecules that play important roles in various biological processes, including morphological changes, migration, proliferation, and apoptosis, and are involved in the progression of many diseases. Abnormal expression or dysregulation of PAK1 and PAK2 may be associated with several diseases, including cancer, neurological diseases, etc. The current research mainly focuses on studying the role of PAK and PAK inhibitors in the regulation of cancer progression, but relatively few reports are available that explore their potential role in cardiovascular diseases. Vascular injury and repair are complex processes involved in many cardiovascular conditions, including atherosclerosis, restenosis, and hypertension. Emerging research suggests that PAK1 and PAK2 have pivotal roles in vascular endothelial cell functions, including migration, proliferation, and angiogenesis. These kinases also modulate vascular smooth muscle relaxation, vascular permeability, and structural alterations, which are critical in the development of atherosclerosis and vascular inflammation. By targeting these activities, PAK proteins are essential for both normal vascular physiology and the pathogenesis of vascular diseases, highlighting their potential as therapeutic targets for vascular health. This review focuses on recent studies that offer experimental insights into the mechanisms by which PAK1 and PAK2 regulate the biological processes of vascular injury and repair and the therapeutic potential of the current existing PAK inhibitors in vascular-related diseases. The limitations of treatment with some PAK inhibitors and the ways that future development can overcome these challenges are also discussed.

Effects of acute creatine supplementation on cardiac and vascular responses in older men; a randomized controlled trial

BACKGROUND AND AIMS

In the recent years creatine has been shown promising results in patients with neurodegenerative diseases, myopathies and dystrophies. Cardiovascular diseases could be another pathology that can benefit from creatine supplementation, considering the influence on the risk factors associated with the development of cardiovascular diseases including reduction in chronic inflammation, and improved control of hyperglycemia and dyslipidemia The aim of the present study was to investigate the impact of short-term creatine supplementation on cardiac and vascular health in older adults.

METHODS

Males between the ages of 55-80 were randomly assigned to three groups: creatine, placebo and control. Creatine or placebo was provided for 7-day supplementation, at a dose of 20 g/day. Testing was performed at the same time of the day at baseline and on the eighth day. Vascular responses were assessed using an arterial pulse wave velocity equipment, while cardiac assessment was performed using an impedance cardiography device.

RESULTS

The placebo group was older (71.1 ± 8.2 yr) compared to creatine (61.4 ± 5.2 yr) and control (62.5 ± 7.1 yr). Cardio-ankle vascular index improved just in the creatine group (8.7 ± 0.5 to 8.2 ± 0.5, p = 0.03). While the upstroke time of the placebo and control groups did not change after 7 days, the creatine group had a nonsignificant reduction, 178.9 ± 26.5 ms to 158.4 ± 28.6 ms, p = 0.07. Similar tendency was seen with the systolic blood pressures, while the placebo and control did not change, the creatine group showed nonsignificant improvement, especially on the right, 144.0 ± 12.7 mmHg to 136.1 ± 13.4 mmHg, p = 0.08. All three groups had similar responses in stroke volume (p = 0.61), contractility index (p = 0.64) and ejection fraction (p = 0.72).

CONCLUSIONS

In older adults, acute creatine supplementation can positively affect vascular parameters of arterial stiffness and atherosclerosis. Creatine supplementation has the potential to serve as a potent adjuvant in the management of CVD for older adults.

CLINICAL TRIAL REGISTRATION

clinicaltrials.gov; ID: NCT05329480.

Berberine ameliorates vascular dysfunction by downregulating TMAO-endoplasmic reticulum stress pathway via gut microbiota in hypertension

The gut microbial metabolite trimethylamine N-oxide (TMAO) is regarded as a novel risk factor for hypertension. Berberine (BBR) exerts cardiovascular protective effects by regulating the gut microbiota-metabolite production pathway. However, whether and how BBR alleviates TMAO-induced vascular dysfunction in hypertension remains unclear. In the present study, we observed that plasma TMAO and related bacterial abundance were significantly elevated and negatively correlated with vascular function in 86 hypertensive patients compared with 46 normotensive controls. TMAO activated endoplasmic reticulum stress (ERS) signaling pathway to promote endothelial cell dysfunction and apoptosis in vitro. BBR (100, 200 mg · kg-1 ·d-1) for 4 weeks ameliorates TMAO-induced vascular dysfunction and ERS activation in a choline-angiotensin II hypertensive mouse model. We found that plasma TMAO levels in 15 hypertensive patients treated with BBR (0.4 g, tid) were reduced by 8.8 % and 16.7 % at months 1 and 3, respectively, compared with pretreatment baseline. The oral BBR treatment also improved vascular function and lowered blood pressure. Faecal 16 S rDNA showed that BBR altered the gut bacterial composition and reduced the abundance of CutC/D bacteria in hypertensive mice and patients. In vitro bacterial cultures and enzyme reaction systems indicated that BBR inhibited the biosynthesis of TMAO precursor in the gut microbiota by binding to and inhibiting the activity of CutC/D enzyme. Our results indicate that BBR improve vascular dysfunction at least partially by decreasing TMAO via regulation of the gut microbiota in hypertension.

Vascular Impairment, Muscle Atrophy, and Cognitive Decline: Critical Age-Related Conditions

The triad of vascular impairment, muscle atrophy, and cognitive decline represents critical age-related conditions that significantly impact health. Vascular impairment disrupts blood flow, precipitating the muscle mass reduction seen in sarcopenia and the decline in neuronal function characteristic of neurodegeneration. Our limited understanding of the intricate relationships within this triad hinders accurate diagnosis and effective treatment strategies. This review analyzes the interrelated mechanisms that contribute to these conditions, with a specific focus on oxidative stress, chronic inflammation, and impaired nutrient delivery. The aim is to understand the common pathways involved and to suggest comprehensive therapeutic approaches. Vascular dysfunctions hinder the circulation of blood and the transportation of nutrients, resulting in sarcopenia characterized by muscle atrophy and weakness. Vascular dysfunction and sarcopenia have a negative impact on physical function and quality of life. Neurodegenerative diseases exhibit comparable pathophysiological mechanisms that affect cognitive and motor functions. Preventive and therapeutic approaches encompass lifestyle adjustments, addressing oxidative stress, inflammation, and integrated therapies that focus on improving vascular and muscular well-being. Better understanding of these links can refine therapeutic strategies and yield better patient outcomes. This study emphasizes the complex interplay between vascular dysfunction, muscle degeneration, and cognitive decline, highlighting the necessity for multidisciplinary treatment approaches. Advances in this domain promise improved diagnostic accuracy, more effective therapeutic options, and enhanced preventive measures, all contributing to a higher quality of life for the elderly population.

Glycolipid Metabolic Disorders, Metainflammation, Oxidative Stress, and Cardiovascular Diseases: Unraveling Pathways

Glycolipid metabolic disorders (GLMDs) are various metabolic disorders resulting from dysregulation in glycolipid levels, consequently leading to an increased risk of obesity, diabetes, liver dysfunction, neuromuscular complications, and cardiorenal vascular diseases (CRVDs). In patients with GLMDs, excess caloric intake and a lack of physical activity may contribute to oxidative stress (OxS) and systemic inflammation. This study aimed to review the connection between GLMD, OxS, metainflammation, and the onset of CRVD. GLMD is due to various metabolic disorders causing dysfunction in the synthesis, breakdown, and absorption of glucose and lipids in the body, resulting in excessive ectopic accumulation of these molecules. This is mainly due to neuroendocrine dysregulation, insulin resistance, OxS, and metainflammation. In GLMD, many inflammatory markers and defense cells play a vital role in related tissues and organs, such as blood vessels, pancreatic islets, the liver, muscle, the kidneys, and adipocytes, promoting inflammatory lesions that affect various interconnected organs through their signaling pathways. Advanced glycation end products, ATP-binding cassette transporter 1, Glucagon-like peptide-1, Toll-like receptor-4, and sphingosine-1-phosphate (S1P) play a crucial role in GLMD since they are related to glucolipid metabolism. The consequences of this is system organ damage and increased morbidity and mortality.

Study on the relationship between body mass index and blood pressure indices in children aged 7-17 during COVID-19

Background

To explore the relationship between body mass index (BMI), age, sex, and blood pressure (systolic blood pressure, SBP; diastolic blood pressure, DBP) in children during COVID-19, providing reference for the prevention and screening of hypertension in children.

Methods

This study adopted a large-scale cross-sectional design to investigate the association between BMI and blood pressure in 7-17-year-old students in City N, China, during COVID-19. Thirty-six primary and secondary schools in City N were sampled using a stratified cluster sampling method. A total of 11,433 students aged 7-17 years in City N, China, were selected for blood pressure (Diastolic blood pressure, DBP, Systolic blood pressure, SBP), height, and weight, Resting heart rate (RHR), chest circumference, measurements, and the study was written using the STROBE checklist. Data analysis was conducted using SPSS 26.0, calculating the mean and standard deviation of BMI and blood pressure for male and female students in different age groups. Regression analysis was employed to explore the impact of BMI, age, and sex on SBP and DBP, and predictive models were established. The model fit was evaluated using the model R2.

Results

The study included 11,287 primary and secondary school students, comprising 5,649 boys and 5,638 girls. It was found that with increasing age, BMI and blood pressure of boys and girls generally increased. There were significant differences in blood pressure levels between boys and girls in different age groups. In regression models, LC, Age, BMI, and chest circumference show significant positive linear relationships with SBP and DBP in adolescents, while RHR exhibits a negative linear relationship with SBP. These factors were individually incorporated into a stratified regression model, significantly enhancing the model's explanatory power. After including factors such as Age, Gender, and BMI, the adjusted R2 value showed a significant improvement, with Age and BMI identified as key predictive factors for SBP and DBP. The robustness and predictive accuracy of the model were further examined through K-fold cross-validation and independent sample validation methods. The validation results indicate that the model has a high accuracy and explanatory power in predicting blood pressure in children of different weight levels, especially among obese children, where the prediction accuracy is highest.

Conclusion

During COVID-19, age, sex, and BMI significantly influence blood pressure in children aged 7-17 years, and predictive models for SBP and DBP were established. This model helps predict blood pressure in children and reduce the risk of cardiovascular diseases. Confirmation of factors such as sex, age, and BMI provide a basis for personalized health plans for children, especially during large-scale infectious diseases, providing guidance for addressing health challenges and promoting the health and well-being of children.

The interactive effect of intra-beat and inter-beat blood pressure variability on neurodegeneration in older adults

Blood pressure variability (BPV) and arterial stiffness are age-related hemodynamic risk factors for neurodegenerative disease, but it remains unclear whether they exert independent or interactive effects on brain health. When combined with high inter-beat BPV, increased intra-beat BPV indicative of arterial stiffness could convey greater pressure wave fluctuations deeper into the cerebrovasculature, exacerbating neurodegeneration. This interactive effect was studied in older adults using multiple markers of neurodegeneration, including medial temporal lobe (MTL) volume, plasma neurofilament light (NfL) and glial fibrillary acidic protein (GFAP). Older adults (N=105) without major neurological or systemic disease were recruited and underwent brain MRI and continuous BP monitoring to quantify inter-beat BPV through systolic average real variability (ARV) and intra-beat variability through arterial stiffness index (ASI). Plasma NfL and GFAP were assessed. The interactive effect of ARV and ASI on MTL atrophy, plasma NfL, and GFAP was studied using hierarchical linear regression. Voxel-based morphometry (VBM) was used to confirm region-of-interest analysis findings. The interaction between higher ARV and higher ASI was significantly associated with left-sided MTL atrophy in both the region-of-interest and false discovery rate-corrected VBM analysis. The interactive effect was also significantly associated with increased plasma NfL, but not GFAP. The interaction between higher ARV and higher ASI is independently associated with increased neurodegenerative markers, including MTL atrophy and plasma NfL, in independently living older adults. Findings could suggest the increased risk for neurodegeneration associated with higher inter-beat BPV may be compounded by increased intra-beat variability due to arterial stiffness.

The effect of cardiorespiratory fitness and habitual physical activity on cardiovascular responses to 2 h of uninterrupted sitting

Prolonged uninterrupted sitting of >3 h has been shown to acutely cause central and peripheral cardiovascular dysfunction. However, individuals rarely sit uninterrupted for >2 h, and the cardiovascular response to this time is currently unknown. In addition, while increased cardiorespiratory fitness (CRF) and habitual physical activity (HPA) are independently associated with improvements in central and peripheral cardiovascular function, it remains unclear whether they influence the response to uninterrupted sitting. This study sought to 1) determine whether 2 h of uninterrupted sitting acutely impairs carotid-femoral pulse wave velocity (cfPWV), femoral ankle PWV (faPWV), and central and peripheral blood pressure and 2) investigate the associations between CRF and HPA versus PWV changes during uninterrupted sitting. Following 2 h of uninterrupted sitting, faPWV significantly increased [mean difference (MD) = 0.26 m·s-1, standard error (SE) = 0.10, P = 0.013] as did diastolic blood pressure (MD = 2.83 mmHg, SE = 1.08, P = 0.014), however, cfPWV did not significantly change. Although our study shows 2 h of uninterrupted sitting significantly impairs faPWV, neither CRF (r = 0.105, P = 0.595) nor HPA (r = -0.228, P = 0.253) was associated with the increases.NEW & NOTEWORTHY We demonstrate that neither cardiorespiratory fitness nor habitual physical activity influence central and peripheral cardiovascular responses to a 2-h bout of uninterrupted sitting in healthy young adults.

The Role of Vascular Endothelial Dysfunction in Hypertension With Hearing Loss

Hypertension can cause hearing loss, but there is no clear definition of the mechanism(s) involved. The study aimed to explore the role of vascular endothelial dysfunction in hypertension with hearing loss. Patients with hypertension were divided into two groups based on hearing loss. Pure tone audiometry (PTA) and endothelial function testing were performed. A total of 216 (432 ears) hypertensive patients were divided into hypertension with hearing loss group (n = 104) and hypertension without hearing loss group (n = 112). The vascular endothelial biomarkers, ET-1 (endothelin-1) and vWF (von Willebrand factor) were significantly higher (P < .05) in the hypertension with hearing loss group. RHI (reactive hyperemia index), ET-1, and vWF were the factors related to hearing loss. The area under the receiver operating characteristic (ROC) curve (AUC) of RHI in the diagnosis of hypertension with hearing loss was .652 (95% CI .552-.751, P = .005), and the Youden index was 26.2%. The AUC of ET-1 was .706 (95% CI .612-.799, P = .001), and the Youden index was 38.9%. The AUC of vWF was .617 (95% CI .512-.721, P = .003), and the Youden index was 28.1%. Vascular endothelial dysfunction may play a role in the pathogenesis of hypertension with hearing loss.

Epithelial Na + Channels Function as Extracellular Sensors

The epithelial Na + channel (ENaC) resides on the apical surfaces of specific epithelia in vertebrates and plays a critical role in extracellular fluid homeostasis. Evidence that ENaC senses the external environment emerged well before the molecular identity of the channel was reported three decades ago. This article discusses progress toward elucidating the mechanisms through which specific external factors regulate ENaC function, highlighting insights gained from structural studies of ENaC and related family members. It also reviews our understanding of the role of ENaC regulation by the extracellular environment in physiology and disease. After familiarizing the reader with the channel's physiological roles and structure, we describe the central role protein allostery plays in ENaC's sensitivity to the external environment. We then discuss each of the extracellular factors that directly regulate the channel: proteases, cations and anions, shear stress, and other regulators specific to particular extracellular compartments. For each regulator, we discuss the initial observations that led to discovery, studies investigating molecular mechanism, and the physiological and pathophysiological implications of regulation. © 2024 American Physiological Society. Compr Physiol 14:5407-5447, 2024.

Enlarged Perivascular Spaces Are Independently Associated with High Pulse Wave Velocity: A Cross-Sectional Study

Background

Recent studies have demonstrated an association between pulse wave velocity (PWV), cerebral small vessel disease (SVD), and cognitive impairment such as Alzheimer's disease. However, the association between brachial-ankle PWV and enlarged perivascular spaces (EPVS), one component of cerebral SVD remains controversial.

Objective

To investigate the relationship between brachial-ankle PWV and EPVS severity in participants without dementia.

Methods

We performed a cross-sectional study of data of 74 participants from sub-analysis of ongoing research. We assessed cognitive function, brachial-ankle PWV, and brain magnetic resonance imaging (MRI) features. Using brain MRI, EPVS were separately assessed as basal ganglia (BG)-EPVS or centrum semiovale (CSO)-EPVS on the basis of their location. The relationship between EPVS severity and brachial-ankle PWV was evaluated using multivariable ordinal logistic regression analyses.

Results

We analyzed 74 participants (women: 47%, mean age: 73 years, mild cognitive impairment [MCI]: 74%). Compared with participants with normal cognition, those with MCI were more likely to have both severe BG-EPVS and severe CSO-EPVS. In multivariable analyses, high brachial-ankle PWV and age were independently associated with BG-EPVS severity (odds ratio [95% confidence interval]: 1.19 [1.02-1.38], 1.09 [1.01-1.17], respectively), whereas only age was independently associated with CSO-EPVS severity. A causal mediation analysis under a counterfactual approach revealed a significant pure natural indirect effect of brachial-ankle PWV on MCI that was mediated by BG-EPVS (estimate: 1.04, 95% CI: 1.01-1.12, p = 0.006).

Conclusions

Brachial-ankle PWV was associated with BG-EPVS severity. High PWV may cause cerebrovascular pulsatility, which accelerates BG-EPVS and may worsen cognitive impairment.

Regulatory T cells and cardiovascular diseases

ABSTRACT

Inflammation is a major underlying mechanism in the progression of numerous cardiovascular diseases (CVDs). Regulatory T cells (Tregs) are typical immune regulatory cells with recognized immunosuppressive properties. Despite the immunosuppressive properties, researchers have acknowledged the significance of Tregs in maintaining tissue homeostasis and facilitating repair/regeneration. Previous studies unveiled the heterogeneity of Tregs in the heart and aorta, which expanded in CVDs with unique transcriptional phenotypes and reparative/regenerative function. This review briefly summarizes the functional principles of Tregs, also including the synergistic effect of Tregs and other immune cells in CVDs. We discriminate the roles and therapeutic potential of Tregs in CVDs such as atherosclerosis, hypertension, abdominal arterial aneurysm, pulmonary arterial hypertension, Kawasaki disease, myocarditis, myocardial infarction, and heart failure. Tregs not only exert anti-inflammatory effects but also actively promote myocardial regeneration and vascular repair, maintaining the stability of the local microenvironment. Given that the specific mechanism of Tregs functioning in CVDs remains unclear, we reviewed previous clinical and basic studies and the latest findings on the function and mechanism of Tregs in CVDs.