Circulatory therapeutics: use of antihypertensive agents and their effects on the vasculature

Osteoprotegerin and Vascular Dysfunction in Patients with Stage 3 Chronic Kidney Disease and Those without Renal Dysfunction: A Case-Control Study

BACKGROUND

Osteoprotegerin (OPG) is a marker of vascular calcification and cardiovascular risk in patients with chronic kidney disease (CKD).

OBJECTIVE

This study aimed to compare and correlate OPG values with flow-mediated dilation (FMD) and pulse wave velocity (PWV) measurements in patients in stage 3 CKD and those without renal dysfunction.

METHODS

This case-control study was conducted in a specialized hypertension center in 2022. A total of 79 patients over 18 years of age participated in the study. The case group consisted of 30 patients with moderate renal dysfunction (CKD stage 3) and the control group included 49 individuals with glomerular filtration rate ≥ 60 mL/min/1.73 m2. The significance level adopted in the statistical analysis was 5%.

RESULTS

Central pulse pressure (cPP), PWV, and augmentation index (AIx) were higher in patients with renal dysfunction. The serum OPG level positively correlated with peripheral and central systolic blood pressure, cPP, PWV, and AIx. Conversely, the serum OPG did not correlate with FMD.

CONCLUSIONS

OPG and PWV are possible biomarkers of vascular dysfunction that are altered in patients with moderate renal dysfunction. Despite limitations of this study, including that it was a case-control study conducted at a single center, it has the potential, as a proof of concept, to generate the hypothesis of OPG and PWV as biomarkers of early vascular damage in this population.

Causes of Chronic Kidney Disease and Their Associations with Cardiovascular Risk and Disease in a Sub-Saharan Low-Income Population

Introduction

The causes of chronic kidney disease (CKD) in people living in Sub-Saharan Africa await identification. Also, whether cardiovascular risk and disease extent differ among patients with different CKD etiologies is uncertain.

Methods

In this prospective cross-sectional study, we examined the presumed causes of chronic kidney disease (CKD) and their relationships with cardiovascular risk and disease in 743 consecutive patients from a sub-Saharan low-income population.

Results

Hypertensive nephropathy (HNP) (60.2%), diabetic nephropathy (DNP) (24.4%), HIV associated CKD (20.0%) and glomerular disease (13.6%) comprised the major CKD etiologies upon enrolment at the hospital nephrology clinic. Pulse pressure was larger in patients with concurrent HNP and DNP than in those with HNP only (p<0.001). Pulse pressure and systolic blood pressure were larger in HNP or/and DNP patients than those with HIV associated CKD and glomerular disease (p=0.04 to <0.001). Cardiovascular disease was more prevalent in patients with HNP and concurrent HNP and DNP than those from other etiologic categories (p<0.05). HNP and DNP were associated with pulsatile pressures (pulse pressure and systolic blood pressure) independent of one another (p<0.01). In adjusted product of coefficient mediation analysis, mean arterial or distending pressure accounted fully for the potential impact of HNP on pulsatile pressures (103.9-115.7%) but not for that of DNP on the respective pressures (-2.0%-(-)7.5%).

Conclusion

HNP is by far the most prevalent presumed cause of CKD in this African population. Cardiovascular risk and disease differ markedly across CKD etiological categories.

Different Doses of Scubitril/Valsartan Compared with Olmesartan in Patients with Essential Hypertension: A Systematic Review and Meta-Analysis

INTRODUCTION

Since sacubitril/valsartan (LCZ696) has neprilysin inhibition and angiotensin receptor-blocking properties, it is anticipated to have strong antihypertensive effects. However, there is not enough evidence to compare the safety and efficacy of sacubitril/valsartan to those of olmesartan in patients with hypertension.

AIM

To compare the efficacy and safety of sacubitril/valsartan versus olmesartan in patients with hypertension.

METHODS

This study follows the guidelines of the Cochrane Handbook. We searched MEDLINE, Cochrane Central, Scopus, and Web of Science databases for relevant clinical trials. We extracted outcome endpoints regarding mean ambulatory systolic/diastolic blood pressure (maSBP/maDBP), mean sitting systolic/diastolic blood pressure (msSBP/msDBP), mean ambulatory/mean sitting pulse pressure (maPP/msPP), the proportion of patients achieving blood pressure control (< 140/90 mmHg), and adverse events. We used Review Manager Software for the conduction of the analysis of this study. The effect estimates of the studies were pooled as Mean difference or risk ratio and 95% confidence interval. We also conducted a subgroup analysis based on the dose of sacubitril/valsartan.

RESULTS

A total of six clinical trials were included. The studies showed an overall low risk of bias. The pooled effect estimate revealed that sacubitril/valsartan significantly reduces maSBP, maDBP, maPP, msSBP, and msDBP measurements compared with olmesartan (p < 0.001). A significantly higher portion of patients achieved blood pressure control in the sacubitril/valsartan group (p < 0.001). The test of subgroup difference showed that 400 mg dose is significantly more effective than 200 mg dose in reducing maSBP. Regarding the safety profile, olmesartan was associated with more side effects due to drug discontinuation and more serious side effects.

CONCLUSION

Sacubitril/valsartan or LCZ696 is more effective and safer than olmesartan for controlling blood pressure in patients with hypertension.

Using Confocal Microscopy to Generate an Accurate Vascular Model for Use in Patient Education Animation

Hypertension is a condition requiring lifelong medication, where patients often feel well with or without treatment. Uncontrolled hypertension, however, can lead to permanent remodelling processes that occur to the vascular structure, which are seldom understood by the public. As a result, a significant burden is placed on healthcare systems globally as a result of the effects of hypertension and lack of adherence to prescribed treatment.Improving patient education through well-designed interactive applications and animation is a known strategy that can improve adherence rates to medication. In the context of hypertension, little attention has been given to helping patients understand the unseen damage that occurs to vessels exposed to high blood pressure. However, generating an accurate representation of a vessel and the changes that occur can be challenging. Using microscopy data is one way for creating an anatomically correct model, but this often needs careful consideration as data cannot be directly imported. Here we describe methods for creating an accurate 3D model of a small artery using confocal microscopy data. This model can then be animated to demonstrate the substructures and pathological changes that occur in hypertensive conditions to better inform patients about the dangers of uncontrolled blood pressure.

Degradation of Premature-miR-181b by the Translin/Trax RNase Increases Vascular Smooth Muscle Cell Stiffness

[Figure: see text].

Nutrient regulation of inflammatory signalling in obesity and vascular disease

Despite obesity and diabetes markedly increasing the risk of developing cardiovascular diseases, the molecular and cellular mechanisms that underlie this association remain poorly characterised. In the last 20 years it has become apparent that chronic, low-grade inflammation in obese adipose tissue may contribute to the risk of developing insulin resistance and type 2 diabetes. Furthermore, increased vascular pro-inflammatory signalling is a key event in the development of cardiovascular diseases. Overnutrition exacerbates pro-inflammatory signalling in vascular and adipose tissues, with several mechanisms proposed to mediate this. In this article, we review the molecular and cellular mechanisms by which nutrients are proposed to regulate pro-inflammatory signalling in adipose and vascular tissues. In addition, we examine the potential therapeutic opportunities that these mechanisms provide for suppression of inappropriate inflammation in obesity and vascular disease.

Relationship between Endothelial Dysfunction and Prevalence of Chronic Kidney Disease: The Circulatory Risk in Communities Study (CIRCS)

AIMS

Patients with chronic kidney disease (CKD) have a higher burden of cardiovascular morbidity and mortality than the general population. Endothelial dysfunction has been suggested to play a role in both glomerular filtration rate loss and cardiovascular damage. Thus, the present study aimed to evaluate the relationship between endothelial dysfunction and the prevalence of CKD in the general Japanese population.

METHODS

We conducted a cross-sectional study of 1042 men and women aged 30-81 years in two communities under the Circulatory Risk in Communities Study between 2013 and 2017. Endothelial function was evaluated by percent change of brachial artery flow-mediated dilation (%FMD) before and after the cuff inflation.

RESULTS

Among the total 1042 participants, there were 62 cases of CKD (~6%). The multivariable odds ratios (ORs) (95% confidence intervals [CIs]) of CKD according to quartiles of %FMD were 2.02 (0.68-5.99), 3.56 (1.27-9.94), and 3.14 (1.10-8.93) for the third to lowest quartile compared with the highest %FMD quartile; p for trend=0.02. The respective multivariable ORs (95% CIs) of CKD in subjects without antihypertensive medication use (39 cases among 886 subjects) were 1.83 (0.46-7.33), 3.41 (0.92-12.61), and 4.60 (1.22-17.31); p for trend=0.01, and that for one-point decrement in %FMD was 1.16 (1.00-1.35); p for interaction with the status of antihypertensive medication use was 0.12.

CONCLUSIONS

Our cross-sectional study suggested the relationship between endothelial dysfunction and the higher prevalence of CKD in the general Japanese population.

Novel Combined Antioxidant Strategy against Hypertension, Acute Myocardial Infarction and Postoperative Atrial Fibrillation

Reactive oxygen species (ROS) play a physiological role in the modulation of several functions of the vascular wall; however, increased ROS have detrimental effects. Hence, oxidative stress has pathophysiological impacts on the control of the vascular tone and cardiac functions. Recent experimental studies reported the involvement of increased ROS in the mechanism of hypertension, as this disorder associates with increased production of pro-oxidants and decreased bioavailability of antioxidants. In addition, increased ROS exposure is found in ischemia-reperfusion, occurring in acute myocardial infarction and cardiac surgery with extracorporeal circulation, among other settings. Although these effects cause major heart damage, at present, there is no available treatment. Therefore, it should be expected that antioxidants counteract the oxidative processes, thereby being suitable against cardiovascular disease. Nevertheless, although numerous experimental studies agree with this notion, interventional trials have provided mixed results. A better knowledge of ROS modulation and their specific interaction with the molecular targets should contribute to the development of novel multitarget antioxidant effective therapeutic strategies. The complex multifactorial nature of hypertension, acute myocardial infarction, and postoperative atrial fibrillation needs a multitarget antioxidant strategy, which may give rise to additive or synergic protective effects to achieve optimal cardioprotection.

Moxibustion for Essential Hypertension and Hypertensive Symptoms: A Systematic Review of 18 Randomized Controlled Trials

INTRODUCTION

This systematic review aims to update the evidence for moxibustion for essential hypertension.

METHODS

Randomized controlled trials (RCTs) comparing moxibustion versus lifestyle intervention or moxibustion plus antihypertensive drugs versus antihypertensive drugs alone were searched in 9 databases up to March 29, 2020. In meta-analyses, mean difference (MD) and proportional odds ratio (pOR) with 95% confidence intervals (CIs) was pooled for continuous and ordinal outcomes, respectively.

RESULTS

Eighteen RCTs were included, involving 1,460 patients. Moxibustion decreased systolic (MD -7.85 mm Hg, 95% CI -9.69 to -6.00, p < 0.00001, I2 = 46%) and diastolic (MD -4.09 mm Hg, 95% CI -5.45 to -2.73, p < 0.0001, I2 = 56%) blood pressures and improved the response to hypotensive treatment (pOR 2.37, 95% CI 1.49-3.75, p = 0.0003, I2 = 57%) significantly more than did the control treatment. Moxibustion also significantly relieved headache and dizziness but the effects changed to be statistically nonsignificant after excluding RCTs with a high risk of bias. Moxibustion did not significantly relieve insomnia and anxiety. No adverse events were reported.

CONCLUSIONS

Based on the current low to moderate quality evidence, our study suggests that moxibustion may have effects on reducing blood pressure. The effects of moxibustion on typical hypertension symptoms and the long-term safety of moxibustion remain uncertain.

Deletion of the microRNA-degrading nuclease, translin/trax, prevents pathogenic vascular stiffness

Vascular stiffness plays a key role in the pathogenesis of hypertension. Recent studies indicate that the age-associated reduction in miR-181b levels in vascular smooth muscle cells (VSMCs) contributes to increased vascular stiffness. As these findings suggest that inhibiting degradation of miR-181b might prevent vascular stiffening, we have assessed whether the microRNA-degrading translin/trax (TN/TX) complex mediates degradation of miR-181b in the aorta.We found that TN^-/- mice display elevated levels of miR-181b expression in the aorta. Therefore, we tested whether TN deletion prevents vascular stiffening in a mouse model of hypertension, induced by chronic high-salt intake (4%NaCl in drinking water for 3 wk; HSW). TN^-/- mice subjected to HSW stress do not show increased vascular stiffness, as monitored by pulse wave velocity and tensile testing. The protective effect of TN deletion in the HSW paradigm appears to be mediated by its ability to increase miR-181b in the aorta since HSW decreases levels of miR-181b in WT mice, but not in TN KO mice. We demonstrate for the first time that interfering with microRNA degradation can have a beneficial impact on the vascular system and identify the microRNA-degrading TN/TX RNase complex as a potential therapeutic target in combatting vascular stiffness.NEW & NOTEWORTHY While the biogenesis and mechanism of action of mature microRNA are well understood, much less is known about the regulation of microRNA via degradation. Recent studies have identified the protein complex, translin(TN)/trax(TX), as a microRNA-degrading enzyme. Here, we demonstrate that TN/TX is expressed in vascular smooth muscle cells. Additionally, deletion of the TN/TX complex selectively increases aortic miR-181b and prevents increased vascular stiffness caused by ingestion of high-salt water. To our knowledge, this is first report describing the role of a microRNA RNAse in cardiovascular biology or pathobiology.

Effect of Different Classes of Antihypertensive Drugs on Endothelial Function and Inflammation

Hypertension is characterized by structural and functional changes in blood vessels that travel with increased arterial stiffness, vascular inflammation, and endothelial dysfunction. Some antihypertensive drugs have been shown to improve endothelial function and reduce levels of inflammatory markers regardless of the effect of blood pressure lowering. Third-generation β-blockers, such as nebivolol and carvedilol, because they have additional properties, have been shown to improve endothelial function in patients with hypertension. Calcium channel antagonists, because they have antioxidant effects, may improve endothelial function and vascular inflammation.The Angiotensin Receptor Blocker (ARBs) are able to improve endothelial dysfunction and vascular inflammation in patients with hypertension and other cardiovascular diseases. Angiotensin converting enzyme (ACE) inhibitors have shown beneficial effects on endothelial function in patients with hypertension and other cardiovascular diseases, however there are few studies evaluating the effect of treatment with this class on the reduction of C-reactive protein (CRP) levels. Further studies are needed to assess whether treatment of endothelial dysfunction and vascular inflammation may improve the prognosis of patients with essential hypertension.

Social jetlag and metabolic control in non-communicable chronic diseases: a study addressing different obesity statuses

Social jetlag – a measure of disruption of the circadian system – has been linked to obesity, but its association with metabolic complications in non-communicable chronic diseases (NCCDs) is unknown in the literature. We examined the associations between social jetlag and obesity status and metabolic parameters among individuals with NCCDs. Patients (n = 792) with NCCDs (obesity, systemic arterial hypertension, type 2 diabetes mellitus or dyslipidaemia) attended clinics of the public health service of the city of Uberlândia, Minas Gerais State, Brazil. They were classified in three obesity statuses: non-obese: BMI < 30 kg/m²; metabolically healthy obese (MHO): BMI ≥ 30 kg/m² and less than three high-risk biomarkers for metabolic syndrome; and metabolically unhealthy obese (MUO): BMI ≥ 30 kg/m² and with high-risk values on three or more biomarkers for metabolic syndrome. After adjustments for confounding variables, social jetlag was positively associated with fasting glucose levels among all subjects (β = 0.08, p = 0.03) and MUO subjects (β = 0.32, p < 0.001). Patients with social jetlag (>1 h) presented a significant odds ratio (OR) of being overweight (OR = 2.0, confidence interval (CI) = 1.2–3.6, p = 0.006) and MUO (OR = 1.8, CI = 1.1–2.8, p = 0.01). These results suggest that social jetlag is associated with a higher risk of overweight and related metabolic complications in individuals with NCCDs.

Women and Chest Pain: Recognizing the Different Faces of Angina in the Emergency Department

Emergency departments (ED) in the United States see over eight million cases of chest pain annually. While a cardinal symptom of acute coronary syndrome (ACS), multiple emergent and non-emergent causes can attribute to chest pain. This case-based perspective describes the different sex-specific causes of angina seen in ED patients. Once coronary artery disease (CAD) is ruled out with standard protocols, microvascular dysfunction is perhaps the most prevalent but under-diagnosed cause of non-CAD related angina in ED patients. Additional causes include coronary artery spasm, coronary artery dissection, coronary artery endothelial dysfunction and myocardial bridging. Non-CAD related angina is associated with persistent chest pain causing poor function, quality of life, and recidivism. Clinicians should consider additional diagnostics to routinely screen for non-CAD related causes of angina in patients with recurrent chest pain. Future work is needed to better define the epidemiological, clinical, biological, and genetic correlates of microvascular dysfunction in these patients.

Chronic antihypertensive treatment improves pulse pressure but not large artery mechanics in a mouse model of congenital vascular stiffness

Increased arterial stiffness is a common characteristic of humans with Williams-Beuren syndrome and mouse models of elastin insufficiency. Arterial stiffness is associated with multiple negative cardiovascular outcomes, including myocardial infarction, stroke, and sudden death. Therefore, identifying therapeutic interventions that improve arterial stiffness in response to changes in elastin levels is of vital importance. The goal of this study was to determine the effect of chronic pharmacologic therapy with different classes of antihypertensive medications on arterial stiffness in elastin insufficiency. Elastin-insufficient mice 4-6 wk of age and wild-type littermates were subcutaneously implanted with osmotic micropumps delivering a continuous dose of one of the following: vehicle, losartan, nicardipine, or propranolol for 8 wk. At the end of treatment period, arterial blood pressure and large artery compliance and remodeling were assessed. Our results show that losartan and nicardipine treatment lowered blood pressure and pulse pressure in elastin-insufficient mice. Elastin and collagen content of abdominal aortas as well as ascending aorta and carotid artery biomechanics were not affected by any of the drug treatments in either genotype. By reducing pulse pressure and shifting the working pressure range of an artery to a more compliant region of the pressure-diameter curve, antihypertensive medications may mitigate the consequences of arterial stiffness, an effect that is drug class independent. These data emphasize the importance of early recognition and long-term management of hypertension in Williams-Beuren syndrome and elastin insufficiency.

Increased vascular smooth muscle cell stiffness: a novel mechanism for aortic stiffness in hypertension

Increased vascular stiffness is fundamental to hypertension, and its complications, including atherosclerosis, suggest that therapy should also be directed at vascular stiffness, rather than just the regulation of peripheral vascular resistance. It is currently held that the underlying mechanisms of vascular stiffness in hypertension only involve the extracellular matrix and endothelium. We hypothesized that increased large-artery stiffness in hypertension is partly due to intrinsic mechanical properties of vascular smooth muscle cells. After confirming increased arterial pressure and aortic stiffness in spontaneously hypertensive rats, we found increased elastic stiffness of aortic smooth muscle cells of spontaneously hypertensive rats compared with Wistar-Kyoto normotensive controls using both an engineered aortic tissue model and atomic force microscopy nanoindentation. Additionally, we observed different temporal oscillations in the stiffness of vascular smooth muscle cells derived from hypertensive and control rats, suggesting that a dynamic component to cellular elastic stiffness is altered in hypertension. Treatment with inhibitors of vascular smooth muscle cell cytoskeletal proteins reduced vascular smooth muscle cell stiffness from hypertensive and control rats, suggesting their participation in the mechanism. This is the first study demonstrating that stiffness of individual vascular smooth muscle cells mediates vascular stiffness in hypertension, a novel concept, which may elucidate new therapies for hypertension and for vascular stiffness.