How to Improve Effectiveness and Adherence to Antihypertensive Drug Therapy: Central Role of Dihydropyridinic Calcium Channel Blockers in Hypertension

The Evolving Role of Calcium Channel Blockers in Hypertension Management: Pharmacological and Clinical Considerations

Worldwide, hypertension is the leading risk factor for cardiovascular disease and death. An estimated 122 million people, per the American Heart Association in 2023, have been diagnosed with this common condition. It is generally agreed that the primary goal in the treatment of hypertension is to reduce overall blood pressure to below 140/90 mmHg, with a more optimal goal of 130/80 mmHg. Common medications for treating hypertension include calcium channel blockers (CCBs), angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, beta-blockers, and diuretics. CCBs are one of the most widely studied agents and are generally recommended as first-line therapy alone and in combination therapies. This is largely based on the vast knowledge of CCB mechanisms and their minimal side effect profile. CCBs can be separated into two classes: dihydropyridine and non-dihydropyridine. Non-dihydropyridine CCBs act on voltage-dependent L-type calcium channels of cardiac and smooth muscle to decrease muscle contractility. Dihydropyridine CCBs act by vasodilating the peripheral vasculature. For many patients with only mild increases in systolic and diastolic blood pressure (e.g., stage 1 hypertension), the medical literature indicates that CCB monotherapy can be sufficient to control hypertension. In this regard, CCB monotherapy in those with stage 1 hypertension reduced renal and cardiovascular complications compared to other drug classes. Combination therapy with CCBs and angiotensin receptor blockers or angiotensin-converting enzyme inhibitors has been shown to be an effective dual therapy based on recent meta-analyses. This article is a review of calcium channel blockers and their use in treating hypertension with some updated and recent information on studies that have re-examined their use. As for new information, we tried to include some information from recent studies on hypertensive treatment involving calcium channel blockers.

Signaling pathways in vascular function and hypertension: molecular mechanisms and therapeutic interventions

Hypertension is a global public health issue and the leading cause of premature death in humans. Despite more than a century of research, hypertension remains difficult to cure due to its complex mechanisms involving multiple interactive factors and our limited understanding of it. Hypertension is a condition that is named after its clinical features. Vascular function is a factor that affects blood pressure directly, and it is a main strategy for clinically controlling BP to regulate constriction/relaxation function of blood vessels. Vascular elasticity, caliber, and reactivity are all characteristic indicators reflecting vascular function. Blood vessels are composed of three distinct layers, out of which the endothelial cells in intima and the smooth muscle cells in media are the main performers of vascular function. The alterations in signaling pathways in these cells are the key molecular mechanisms underlying vascular dysfunction and hypertension development. In this manuscript, we will comprehensively review the signaling pathways involved in vascular function regulation and hypertension progression, including calcium pathway, NO-NOsGC-cGMP pathway, various vascular remodeling pathways and some important upstream pathways such as renin-angiotensin-aldosterone system, oxidative stress-related signaling pathway, immunity/inflammation pathway, etc. Meanwhile, we will also summarize the treatment methods of hypertension that targets vascular function regulation and discuss the possibility of these signaling pathways being applied to clinical work.

Oxidative Regulation of Vascular Cav1.2 Channels Triggers Vascular Dysfunction in Hypertension-Related Disorders

Blood pressure is determined by cardiac output and peripheral vascular resistance. The L-type voltage-gated Ca²⁺ (Ca_v1.2) channel in small arteries and arterioles plays an essential role in regulating Ca²⁺ influx, vascular resistance, and blood pressure. Hypertension and preeclampsia are characterized by high blood pressure. In addition, diabetes has a high prevalence of hypertension. The etiology of these disorders remains elusive, involving the complex interplay of environmental and genetic factors. Common to these disorders are oxidative stress and vascular dysfunction. Reactive oxygen species (ROS) derived from NADPH oxidases (NOXs) and mitochondria are primary sources of vascular oxidative stress, whereas dysfunction of the Ca_v1.2 channel confers increased vascular resistance in hypertension. This review will discuss the importance of ROS derived from NOXs and mitochondria in regulating vascular Ca_v1.2 and potential roles of ROS-mediated Ca_v1.2 dysfunction in aberrant vascular function in hypertension, diabetes, and preeclampsia.

Prevalence and determinants of medications non-adherence among patients with uncontrolled hypertension in primary care setting in Sarawak, Malaysia: A cross-sectional study

INTRODUCTION

Non-adherence to antihypertensive medications is a leading cause of uncontrolled hypertension and its complications. However, data on the factors associated with non-adherence to antihypertensive medications in the communities of Sarawak, Malaysia, are limited. This study aimed to examine the prevalence and determinants of medication non-adherence among patients with uncontrolled hypertension.

METHOD

A cross-sectional study was conducted using the systematic sampling method in four government primary healthcare clinics in Sarawak. A self-administered questionnaire was used to obtain socio-demographic data and evaluate non-adherence. Blood pressure was measured, and relevant clinical variables were collected from medical records. Multivariate logistic regression was used to determine the determinants of medication non-adherence.

RESULTS

A total of 488 patients with uncontrolled hypertension were enrolled in this study. The prevalence of medication non-adherence was 39.3%. There were four predictors of medication non-adherence among the patients with uncontrolled hypertension: tertiary educational level (odds ratio [OR]=4.21, 95% confidence interval [CI] = 1.67-10.61, P=0.010), complementary alternative medication (0R=2.03, 95% CI=1.12-3.69, P=0.020), non-usage of calcium channel blockers (0R=1.57, 95% CI=1.02-2.41, P=0.039) and 1 mmHg increase in the systolic blood pressure (0R=1.03, 95% CI=1.00-1.05, P=0.006).

CONCLUSION

Because of the high prevalence of medication non-adherence among patients with uncontrolled hypertension, primary care physicians should be more vigilant in identifying those at risk of being non-adherent. Early intervention should be conducted to address non-adherence for blood pressure control.

Braylin induces a potent vasorelaxation, involving distinct mechanisms in superior mesenteric and iliac arteries of rats

Arterial hypertension is a risk factor for various cardiovascular and renal diseases, representing a major public health challenge. Although a wide range of treatment options are available for blood pressure control, many hypertensive individuals remain with uncontrolled hypertension. Thus, the search for new substances with antihypertensive potential becomes necessary. Coumarins, a group of polyphenolic compounds derived from plants, have attracted intense interest due to their diverse pharmacological properties, like potent antihypertensive activities. Braylin (6-methoxyseselin) is a coumarin identified in the Zanthoxylum tingoassuiba species, described as a phosphodiesterase-4 (PDE4) inhibitor. Although different coumarin compounds have been described as potent antihypertensive agents, the activity of braylin on the cardiovascular system has yet to be investigated. To investigate the vasorelaxation properties of braylin and its possible mechanisms of action, we performed in vitro studies using superior mesenteric arteries and the iliac arteries isolated from rats. In this study, we demonstrated, for the first time, that braylin induces potent vasorelaxation, involving distinct mechanisms from two different arteries, isolated from rats. A possible inhibition of phosphodiesterase, altering the cyclic adenosine monophosphate (cAMP)/cAMP-dependent protein kinase (PKA) pathway, may be correlated with the biological action of braylin in the mesenteric vessel, while in the iliac artery, the biological action of braylin may be correlated with increase of cyclic guanosine monophosphate (cGMP), followed by BKCa, Kir, and Kv channel activation. Together, these results provide evidence that braylin can represent a potential therapeutic use in preventing and treating cardiovascular diseases.

Effect of Different Blood-Pressure-Lowering Regimens on the Blood Pressure Control among Hypertensive Patients Treated in Hospital Conditions

BACKGROUND

Scientific references lack sufficient amount of data on analyses of the reasons for hospital admissions or assessment of efficacy of arterial hypertension treatment at hospitals.

OBJECTIVES

The aim of the study was to evaluate the efficacy of antihypertensive drug therapy on the blood pressure control among hospitalized hypertensive patients. Methodology. A cross-sectional retrospective study consisted of 204 patients aged 18-65 years admitted to the hospital due to hypertension between January 2018 and December 2018. The study was based on analysis of electronic records, obtained from the medical database of the selected healthcare facility.

RESULTS

As a result of the treatment applied at the hospital, 65.19% of the patients achieved the desired degree of blood pressure normalization (≤130/80 mmHg). Vast majority of the patients during their stay at the ward would receive three or more hypertensive drugs (63.73%). The most frequently prescribed antihypertensive drug combinations included bitherapies such as diuretics + ACEI and ACEI + β-blockers and tritherapy such as diuretics + β-blockers and calcium channel antagonists and diuretics + ACEI and ARBs. The highest blood-pressure lowering effects were observed among patients receiving combination therapy of a ACEI, a diuretic, and a ARBs. Tritherapy induced a significant mean reduction of inpatients`s SBP compared with bitherapy (p=0.0001).

CONCLUSION

During their hospital stay, vast majority of patients (65.19%) achieved normal values of blood pressure, mostly owing to combined treatment with several hypertensive drugs. Efficacy of the most frequently used combinations of hypertensive drugs in normalizing arterial pressure varies.

Identification of compounds that rescue otic and myelination defects in the zebrafish adgrg6 (gpr126) mutant

Adgrg6 (Gpr126) is an adhesion class G protein-coupled receptor with a conserved role in myelination of the peripheral nervous system. In the zebrafish, mutation of adgrg6 also results in defects in the inner ear: otic tissue fails to down-regulate versican gene expression and morphogenesis is disrupted. We have designed a whole-animal screen that tests for rescue of both up- and down-regulated gene expression in mutant embryos, together with analysis of weak and strong alleles. From a screen of 3120 structurally diverse compounds, we have identified 68 that reduce versican b expression in the adgrg6 mutant ear, 41 of which also restore myelin basic protein gene expression in Schwann cells of mutant embryos. Nineteen compounds unable to rescue a strong adgrg6 allele provide candidates for molecules that may interact directly with the Adgrg6 receptor. Our pipeline provides a powerful approach for identifying compounds that modulate GPCR activity, with potential impact for future drug design.

Pigments from Filamentous Ascomycetes for Combination Therapy

Filamentous ascomycetes (Neurospora and Monascus) have been studied for a long time because of their production of secondary metabolites such as microbial pigments. The ascomycetes represent an interesting group of compounds with high potential for medicinal applications. Many recent studies have shown their efficacy in the treatment of serious pathological states such as oncological diseases, neurodegenerative diseases and hyperlipidaemia. Nevertheless, the clinical usability of ascomycetes is still limited. However, this problem can be solved by the use of these compounds with combinations of other therapeutic agents. This strategy can suppress their side effects and improve their therapeutic efficacy. Moreover, their co-application can significantly enhance conventional therapies that are used. This review summarizes and discusses the general principles of this approach, introduced and supported by numerous examples. In addition, the prediction of the future potential application of this methodology is included.