Beta-Adrenergic Receptor Blockers in Hypertension: Alive and Well

Impact of blood pressure and antihypertensive drug classes on intracranial aneurysm: a Mendelian randomization study

BACKGROUND

Blood pressure is a risk factor for intracranial aneurysms (IA). Nevertheless, whether various antihypertensive drug classes discriminate in reducing IA risk is unclear.

METHODS

Genome-wide association study summary statistics for systolic blood pressure (SBP), diastolic blood pressure (DBP), IA (non-ruptured), and IA [subarachnoid hemorrhage (SAH)] were downloaded. To proxy the effects of antihypertensive drugs, genetic variants associated with SBP adjacent to the coding regions of different antihypertensive drugs were selected. The inverse-variance-weighted (IVW) method was employed as the primary method for causal estimation. In addition, three additional MR methods and sensitivity tests were utilized to assess the reliability.

RESULTS

Elevated blood pressure significantly increases the risk of IA: (i) SBP-IA (non-ruptured): odds ratio (OR) = 1.046, 95 % confidence interval (CI): 1.032-1.061, P = 1.05E-10; (ii) SBP-IA (SAH): OR = 1.040, 95 % CI: 1.030-1.050, P = 2.56E-15; (iii) DBP-IA (non-ruptured): OR = 1.082, 95 % CI: 1.056-1.110, P = 3.15E-10; (iv) DBP-IA (SAH): OR = 1.066, 95 % CI: 1.047-1.085, P = 1.25E-12. In addition, among calcium channel blockers (CCBs), beta-blockers (BBs), and thiazide diuretics (TDs), only SBP mediated by TDs target genes significantly increased the risk of IA (non-rupture) (OR = 1.164, 95 % CI: 1.060-1.279, P = 0.001) and IA (SAH) (OR = 1.136, 95 % CI: 1.063-1.214, P = 1.58E-04), while SBP mediated by target genes of BBs or CCBs did not causally associate with IA.

CONCLUSION

Elevated blood pressure significantly increases IA risk, while TDs may be a promising antihypertensive medication for reducing IA risk. Further research with larger cohorts is essential for validation.

Beta-blockers in patients with liver cirrhosis: Pragmatism or perfection?

With increasing decompensation, hyperdynamic circulatory disturbance occurs in liver cirrhosis despite activation of vasoconstrictors. Here, the concept of a therapy with non-selective beta-blockers was established decades ago. They lower elevated portal pressure, protect against variceal hemorrhage, and may also have pleiotropic immunomodulatory effects. Recently, the beneficial effect of carvedilol, which blocks alpha and beta receptors, has been highlighted. Carvedilol leads to "biased-signaling" via recruitment of beta-arrestin. This effect and its consequences have not been sufficiently investigated in patients with liver cirrhosis. Also, a number of questions remain open regarding the expression of beta-receptors and its intracellular signaling and the respective consequences in the intra- and extrahepatic tissue compartments. Despite the undisputed role of non-selective beta-blockers in the treatment of liver cirrhosis, we still can improve the knowledge as to when and how beta-blockers should be used in which patients.

Maternal Low Volume Circulation Relates to Normotensive and Preeclamptic Fetal Growth Restriction

This narrative review summarizes current evidence on the association between maternal low volume circulation and poor fetal growth. Though much work has been devoted to the study of cardiac output and peripheral vascular resistance, a low intravascular volume may explain why high vascular resistance causes hypertension in women with preeclampsia (PE) that is associated with fetal growth restriction (FGR) and, at the same time, presents with normotension in FGR itself. Normotensive women with small for gestational age babies show normal gestational blood volume expansion superimposed upon a constitutionally low intravascular volume. Early onset preeclampsia (EPE; occurring before 32 weeks) is commonly associated with FGR, and poor plasma volume expandability may already be present before conception, thus preceding gestational volume expansion. Experimentally induced low plasma volume in rodents predisposes to poor fetal growth and interventions that enhance plasma volume expansion in FGR have shown beneficial effects on intrauterine fetal condition, prolongation of gestation and birth weight. This review makes the case for elevating the maternal intravascular volume with physical exercise with or without Nitric Oxide Donors in FGR and EPE, and evaluating its role as a potential target for prevention and/or management of these conditions.

Role of Chrononutrition in the Antihypertensive Effects of Natural Bioactive Compounds

Hypertension (HTN) is one of the main cardiovascular risk factors and is considered a major public health problem. Numerous approaches have been developed to lower blood pressure (BP) in hypertensive patients, most of them involving pharmacological treatments. Within this context, natural bioactive compounds have emerged as a promising alternative to drugs in HTN prevention. This work reviews not only the mechanisms of BP regulation by these antihypertensive compounds, but also their efficacy depending on consumption time. Although a plethora of studies has investigated food-derived compounds, such as phenolic compounds or peptides and their impact on BP, only a few addressed the relevance of time consumption. However, it is known that BP and its main regulatory mechanisms show a 24-h oscillation. Moreover, evidence shows that phenolic compounds can interact with clock genes, which regulate the biological rhythm followed by many physiological processes. Therefore, further research might be carried out to completely elucidate the interactions along the time–nutrition–hypertension axis within the framework of chrononutrition.

Overcoming Drug Resistance in Advanced Prostate Cancer by Drug Repurposing

Prostate cancer (PCa) is the second most common cancer in men. Common treatments include active surveillance, surgery, or radiation. Androgen deprivation therapy and chemotherapy are usually reserved for advanced disease or biochemical recurrence, such as castration-resistant prostate cancer (CRPC), but they are not considered curative because PCa cells eventually develop drug resistance. The latter is achieved through various cellular mechanisms that ultimately circumvent the pharmaceutical's mode of action. The need for novel therapeutic approaches is necessary under these circumstances. An alternative way to treat PCa is by repurposing of existing drugs that were initially intended for other conditions. By extrapolating the effects of previously approved drugs to the intracellular processes of PCa, treatment options will expand. In addition, drug repurposing is cost-effective and efficient because it utilizes drugs that have already demonstrated safety and efficacy. This review catalogues the drugs that can be repurposed for PCa in preclinical studies as well as clinical trials.

Pharmacologic Management of Coronary Artery Ectasia

Coronary artery ectasia (CAE) is a rare form of aneurysmal coronary heart disease. It is defined as a dilatation of the coronary artery by more than one-third of its length and with a diameter 1.5 times of a normal coronary artery adjacent to it. This condition increases the risk of angina pectoris and acute coronary syndrome. Hence, we discuss the pharmacologic options for primary and secondary prevention of CAE complications. Antiplatelets such as aspirin are considered the mainstay of treatment in patients with CAE. Anticoagulants such as warfarin are warranted on a case-by-case basis to prevent thrombus formation depending on the presence of concomitant obstructive coronary artery disease and the patient’s risk of bleeding. Since atherosclerosis is the most common cause of CAE, statins are indicated in all patients for primary prevention. Angiotensin-converting enzyme (ACE) inhibitors may be indicated, especially in hypertensive patients, due to their anti-inflammatory properties. Beta-blockers may be indicated due to their antihypertensive and anti-ischemic effects. Calcium (Ca) channel blockers may be needed to prevent coronary vasospasm. Nitrates are generally contraindicated as they may lead to worsening of symptoms. Other antianginal medications such as trimetazidine can improve exercise tolerance with no reported adverse events in these patients.

The cytotoxic and apoptotic effects of beta-blockers with different selectivity on cancerous and healthy lung cell lines

β-blockers having specific affinities to β-adrenergic receptors are routinely used to treat cardiovascular problems. Additionally, it has been demonstrated that these drugs can be effective in treating apoptosis-related diseases. The current study was conducted to investigate the cytotoxic and apoptotic effects of β-1 selective esmolol, β-2 selective ICI-118,551, and non-selective nadolol blockers on the cancerous and healthy lung cells. MTT test was used to evaluate cytotoxicity. Apoptotic actions were examined by using Annexin V-FITC/PI assay, JC-1 staining, ROS test, and the determination of the caspase-4 and -9, Bcl-2, Bax, Bax/Bcl-2, and JNK levels. Although the MRC-5 showed greater resistance than A549 cells, the β-blockers at 150-250 µM exhibited different levels of cytotoxic effect on both lung cell lines. Esmolol was found to be the most ineffective blocker and the increases in Bcl-2 protein levels were appeared to be effective in resistance to this drug. The increases in reactive oxygen species (ROS) together with the increase in caspase-4 and Bax protein levels have been shown to play a role in ICI-118,551 induced lung cell death. Nadolol was the most effective blocker increasing the total apoptotic cell population in both lung cells, which was based on both mitochondrial and endoplasmic reticulum stress. When the selectivities of the β-blockers are considered, it seems that β-2 specific antagonism predominantly mediated the death of lung cells, and the overwhelming factors causing apoptosis mainly varied depending on the selectivity of the blockers.

Unintended Effects of GPCR-Targeted Drugs on the Cancer Phenotype

G protein-coupled receptors (GPCRs) are the most common class of therapeutic targets, accounting for ~35% of all FDA-approved drugs. Cancer patients receive numerous medications not only to combat cancer but also to alleviate pain, nausea, and anxiety, many of which target GPCRs. Emerging evidence has implicated GPCRs as drivers of cancer progression, therapeutic resistance, and metastasis. Therefore, the effects of commonly prescribed GPCR-targeted drugs must be reevaluated in the context of cancer. Epidemiological and experimental evidence indicate that widely used GPCR-targeted drugs may promote or inhibit cancer progression. It is crucial that we more fully understand the indirect effects of GPCR-targeted drugs on the cancer phenotype. This review summarizes recent advances in characterizing these interactions and highlights future research opportunities.

Facile Synthesis of Propranolol and Novel Derivatives

Propranolol is one of the first medications of the beta-blocker used for antihypertensive drugs. This study reports the facile route for the synthesis of propranolol and its novel derivatives. Herein, propranolol synthesis proceeded from 1-naphthol and isopropylamine under mild and less toxic conditions. Novel propranolol derivatives were designed by reactions of propranolol with benzoyl chloride, pyridinium chlorochromate, and n-butyl bromide through esterification, oxidation reduction, and alkylation, respectively. The isolation and purity of compounds were conducted using column chromatography and thin-layer chromatography. Mass spectrometry and 1H-NMR spectroscopy were applied to identify new compounds structure. Propranolol derivatives from 2-chlorobenzoyl chloride (compound 3), 2-fluorobenzoyl chloride (compound 5), and especially acetic anhydride (compound 6) manifested high yields and significantly increased water solubility. Six semisynthetic propranolol derivatives promise to improve antioxidative and biological activities.

Synthetic repurposing of drugs against hypertension: a datamining method based on association rules and a novel discrete algorithm

BACKGROUND

Drug repurposing aims to detect the new therapeutic benefits of the existing drugs and reduce the spent time and cost of the drug development projects. The synthetic repurposing of drugs may prove to be more useful than the single repurposing in terms of reducing toxicity and enhancing efficacy. However, the researchers have not given it serious consideration. To address the issue, a novel datamining method is introduced and applied to repositioning of drugs for hypertension (HT) which is a serious medical condition and needs some improved treatment plans to help treat it.

RESULTS

A novel two-step data mining method, which is based on the If-Then association rules as well as a novel discrete optimization algorithm, was introduced and applied to the synthetic repurposing of drugs for HT. The required data were also extracted from DrugBank, KEGG, and DrugR+ databases. The findings indicated that based on the different statistical criteria, the proposed method outperformed the other state-of-the-art approaches. In contrast to the previously proposed methods which had failed to discover a list on some datasets, our method could find a combination list for all of them.

CONCLUSION

Since the proposed synthetic method uses medications in small dosages, it might revive some failed drug development projects and put forward a suitable plan for treating different diseases such as COVID-19 and HT. It is also worth noting that applying efficient computational methods helps to produce better results.

Neurocardiac regulation: from cardiac mechanisms to novel therapeutic approaches

Cardiac sympathetic overactivity is a well-established contributor to the progression of neurogenic hypertension and heart failure, yet the underlying pathophysiology remains unclear. Recent studies have highlighted the importance of acutely regulated cyclic nucleotides and their effectors in the control of intracellular calcium and exocytosis. Emerging evidence now suggests that a significant component of sympathetic overactivity and enhanced transmission may arise from impaired cyclic nucleotide signalling, resulting from compromised phosphodiesterase activity, as well as alterations in receptor-coupled G-protein activation. In this review, we address some of the key cellular and molecular pathways that contribute to sympathetic overactivity in hypertension and discuss their potential for therapeutic targeting.

Beta-Blockers and Cancer: Where Are We?

Cancer is one of the leading causes of death worldwide. After diagnosis, cancer treatment may involve radiotherapy, chemotherapy, and surgery. Several of the approaches used to treat cancer also attack normal cells and, thus, there is the need for more effective treatments that decrease the toxicity to normal cells and increase the success rates of treatment. The use of beta-blockers in cancer has been studied for their antagonist action on the adrenergic system through inhibition of beta-adrenergic receptors. Besides regulating processes such as blood pressure, heart rate, and airway strength or reactivity, beta-blockers block mechanisms that trigger tumorigenesis, angiogenesis, and tumor metastasis. This study presents a literature review of the available studies addressing cancer treatments and beta-blockers. Overall, data suggest that propranolol may be used as a complement for the treatment of several types of cancer due to its ability to improve cancer outcomes by decreasing cancer cell proliferation rates. Nonetheless, additional in vitro studies should be performed to fully understand the protective role of BBs in cancer patients.

Study of the atenolol degradation using a Nb/BDD electrode in a filter-press reactor

The present paper deals with the atenolol (ATL) degradation by advanced anodic oxidation using a boron-doped diamond anode supported on niobium (Nb/BDD). Cyclic voltammetry performed on this electrode revealed that it presents a high quality (diamond-sp³/sp²-carbon ratio), high potential for OER and that ATL can be oxidized directly and/or indirectly by the electrogenerated oxidants, such as hydroxyl radicals, persulfate ions and sulfate radicals. Electrolysis experiments demonstrated that ATL degradation and mineralization follow a mixed (first and zero) order kinetics depending on the applied current density. At high applied current densities, the amount of OH radicals is very high and the overall reaction is limited by the transport of ATL (pseudo first-order kinetics) whereas for low applied current densities, the rate of OH radicals generation at the anode is slower than the rate of arrival of ATL molecules (pseudo-zero order kinetics). Estimated values of k_zero and k_first based on the assumption of pseudo-zero or pseudo-first order kinetics were carried oud as a function of the supporting electrolyte concentration, indicating that both parameters increased with its concentration due the higher production of sulfate reactive species that play an important role in degradation. Finally, MCE increased with the decrease of current density, due to the lower amount of OH present in solution, since this species could be rapidly wasted in parasitic reactions; and the increase of sulfate concentration due to the more efficient production of persulfate.

Neurotransmitter Switching Coupled to β-Adrenergic Signaling in Sympathetic Neurons in Prehypertensive States

Single or combinatorial administration of β-blockers is a mainstay treatment strategy for conditions caused by sympathetic overactivity. Conventional wisdom suggests that the main beneficial effect of β-blockers includes resensitization and restoration of β1-adrenergic signaling pathways in the myocardium, improvements in cardiomyocyte contractility, and reversal of ventricular sensitization. However, emerging evidence indicates that another beneficial effect of β-blockers in disease may reside in sympathetic neurons. We investigated whether β-adrenoceptors are present on postganglionic sympathetic neurons and facilitate neurotransmission in a feed-forward manner. Using a combination of immunocytochemistry, RNA sequencing, Förster resonance energy transfer, and intracellular Ca2+ imaging, we demonstrate the presence of β-adrenoceptors on presynaptic sympathetic neurons in both human and rat stellate ganglia. In diseased neurons from the prehypertensive rat, there was enhanced β-adrenoceptor-mediated signaling predominantly via β2-adrenoceptor activation. Moreover, in human and rat neurons, we identified the presence of the epinephrine-synthesizing enzyme PNMT (phenylethanolamine-N-methyltransferase). Using high-pressure liquid chromatography with electrochemical detection, we measured greater epinephrine content and evoked release from the prehypertensive rat cardiac-stellate ganglia. We conclude that neurotransmitter switching resulting in enhanced epinephrine release, may provide presynaptic positive feedback on β-adrenoceptors to promote further release, that leads to greater postsynaptic excitability in disease, before increases in arterial blood pressure. Targeting neuronal β-adrenoceptor downstream signaling could provide therapeutic opportunity to minimize end-organ damage caused by sympathetic overactivity.

Propranolol sensitizes prostate cancer cells to glucose metabolism inhibition and prevents cancer progression

Propranolol, a widely used non-selective beta-adrenergic receptor blocker, was recently shown to display anticancer properties. Its potential to synergize with certain drugs has been also outlined. However, it is necessary to take into account all the properties of propranolol to select a drug that could be efficiently combined with. Propranolol was reported to block the late phase of autophagy. Hence, we hypothesized that in condition enhancing autophagy flux, cancer cells should be especially sensitive to propranolol. 2DG, a glycolysis inhibitor, is an anti-tumor agent having limited effect in monotherapy notably due to induction of pro-survival autophagy. Here, we report that treatment of cancer cells with propranolol in combination with the glycolysis inhibitor 2DG induced a massive accumulation of autophagosome due to autophagy blockade. The propranolol +2DG treatment efficiently prevents prostate cancer cell proliferation, induces cell apoptosis, alters mitochondrial morphology, inhibits mitochondrial bioenergetics and aggravates ER stress in vitro and also suppresses tumor growth in vivo. Our study underlines for the first time the interest to take advantage of the ability of propranolol to inhibit autophagy to design new anti-cancer therapies.

Synergistic effects of Chuanxiong-Chishao herb-pair on promoting angiogenesis at network pharmacological and pharmacodynamic levels

OBJECTIVE

To investigate the synergistic effects of Chuanxiong-Chishao herb-pair (CCHP) on promoting angiogenesis in silico and in vivo.

METHODS

The mechanisms of action of an herb-pair, Chuanxiong-Chishao, were investigated using the network pharmacological and pharmacodynamic strategies involving computational drug target prediction and network analysis, and experimental validation. A set of network pharmacology methods were created to study the herbs in the context of targets and diseases networks, including prediction of target profiles and pharmacological actions of main active compounds in Chuanxiong and Chishao. Furthermore, the therapeutic effects and putative molecular mechanisms of Chuanxiong-Chishao actions were experimentally validated in a chemical-induced vascular insuffificiency model of transgenic zebrafifish in vivo. The mRNA expression of the predicted targets were further analyzed by real-time polymerase chain reaction (RT-PCR).

RESULTS

The computational prediction results found that the compounds in Chuanxiong have antithrombotic, antihypertensive, antiarrhythmic, and antiatherosclerotic activities, which were closely related to protecting against hypoxic-ischemic encephalopathy, ischemic stroke, myocardial infarction and heart failure. In addition, compounds in Chishao were found to participate in anti-inflflammatory effect and analgesics. Particularly, estrogen receptor α (ESRα) and hypoxia-inducible factor 1-α (HIF-1α) were the most important potential protein targets in the predicted results. In vivo experimental validation showed that post-treatment of tetramethylpyrazine hydrochloride (TMP•HCl) and paeoniflorin (PF) promoted the regeneration of new blood vessels in zebrafifish involving up-regulating ESRα mRNA expression. Co-treatment of TMP•HCl and PF could enhance the vessel sprouting in chemical-induced vascular insuffificiency zebrafifish at the optimal compatibility proportion of PF 10 μmol/L with TMP•HCl 1 μmol/L.

CONCLUSIONS

The network pharmacological strategies combining drug target prediction and network analysis identified some putative targets of CCHP. Moreover, the transgenic zebrafifish experiments demonstrated that the Chuanxiong-Chishao combination synergistically promoted angiogenic activity, probably involving ESRα signaling pathway.

Acupuncture Attenuates Renal Sympathetic Activity and Blood Pressure via Beta-Adrenergic Receptors in Spontaneously Hypertensive Rats

The sympathetic nervous system, via epinephrine and norepinephrine, regulates β-adrenergic receptor (β-AR) expression, and renal sympathetic activation causes sustained increases in blood pressure by enhanced renin release. In this study, we aim to investigate the effect and underlying mechanism of acupuncture at Taichong (LR3) on renal sympathetic activity in spontaneously hypertensive rats. Unanesthetized rats were subject to daily acupuncture for 2 weeks. Mean blood pressure (MBP) and heart rate variability (HRV) were monitored at days 0, 7, and 14 by radiotelemetry. After euthanasia on the 14th day, blood and the kidneys were collected and subject to the following analyses. Epinephrine and norepinephrine were detected by ELISA. The expression of β-ARs was studied by western blotting and PCR. The renin content was analyzed by radioimmunoassay. 14-day acupuncture significantly attenuates the increase of MBP. The HRV indices, the standard deviation of all normal NN intervals (SDNN), and the ratio of the low-frequency component to the high-frequency component (LF/HF) were improved following acupuncture. Renal sympathetic activation induced upregulation of epinephrine, norepinephrine, and renin content were attenuated by acupuncture. In addition, acupuncture decreased β1-AR expression and improved β2-AR expression. These results indicated that acupuncture relieves the increased MBP via the regulation of renal sympathetic activity and β-ARs.