Propranolol

Efficacy of prescribing Inderal for polymorphic ventricular tachycardia in a young patient with the normal QT interval: A case report study

Polymorphic ventricular tachycardia (PVT) is a group of life-threatening heart rhythm disorders. These arrhythmias share similar electrocardiographic characteristics but require different modes of therapy for effective treatment. It is important to note that the medications that are considered the first-line treatment for one type of PVT may not be appropriate for another type, and may worsen the condition. Therefore, it is crucial to accurately diagnose the type of PVT before initiating treatment to provide the most effective therapy for the patient. A 42-year-old man was admitted to the emergency department with dyspnea, Levine sign, and severe chest pain. His electrocardiogram showed ST elevation, and the QT interval was normal. The patient was sent to the cath lab based on the treatment protocols. According to the results of angiography, three coronary arteries were severely obstructed. His coronary arteries did not open during percutaneous coronary intervention; thus, the healthcare team decided on open heart surgery. He suffered from recurrent PVT following open heart surgery and did not respond to any of the drugs suitable for this type of tachycardia. Inderal prevented the recurrence of ventricular tachycardia (VT) in a patient with polymorphic VT without QT prolongation, contrary to the healthcare team's expectations. Inderal was used as the last line of treatment because this patient's arrhythmia was polymorphic VT without QT prolongation. Inderal is typically used for treating VT in patients with long QT syndromes and heart structural disorders. This case report aims to highlight the impact of Inderal on polymorphic tachycardia, specifically in cases where the QT interval is not elongated. In this particular case, the standard treatment approaches were ineffective in preventing reversibility, but Inderal proved to be successful. Therefore, we feel it is important to document and share this case.

European Headache Federation (EHF) critical re-appraisal and meta-analysis of oral drugs in migraine prevention - part 4: propranolol

OBJECTIVE

The aim of this paper is to critically re-appraise the published trials assessing propranolol for migraine prophylaxis.

METHODS

We report methods and results following the Preferred Reporting Items for Systematic Reviews (PRISMA), by searching MEDLINE, EMBASE, Cochrane CENTRAL, and ClinicalTrials.gov for randomized trials of pharmacologic treatments for migraine prophylaxis. We included randomized trials that compared propranolol with placebo for migraine prophylaxis in adults. The outcomes of interest were informed by the Core outcome set for preventive intervention trials in chronic and episodic migraine (COSMIG) and include the proportion of patients who experience a 50% or more reduction in monthly migraine days, the reduction of monthly migraine days, and the number of adverse events leading to discontinuation. We assessed risk of bias by using a modified Cochrane RoB (risk of bias) 2.0 tool and the certainty of evidence by using the GRADE approach.

RESULTS

Our search yielded twenty trials (n = 1291 patients) eligible for data synthesis and analysis. The analysis revealed a moderate certainty evidence that propranolol leads to a reduction in monthly migraine days versus placebo (-1.27; 95% CI: -2.25 to -0.3). We found moderate certainty evidence that propranolol increases the proportion of patients who experience a 50% or more reduction in monthly migraine days, compared to placebo with a relative risk of 1.65 (95% CI 1.41 to 1.93); absolute risk difference: 179 more per 1,000 (95% CI 113 to 256). We found high certainty evidence that propranolol increases the proportion of patients who discontinue due to adverse events compared to placebo with a risk difference of 0.02 (95% CI 0.00 to 0.03); absolute risk difference: 20 more per 1,000 (95% CI 0 to 30).

CONCLUSIONS

The present meta-analysis shows that propranolol has a prophylactic role in migraine, with an overall acceptable tolerability profile. Combining these results with its long-standing use and its global availability at a low cost confirms its role as a first line agent in the prophylaxis of migraine.

The role of beta-adrenoreceptors in postoperative ileus in rats

The aim of the research was to evaluate the influence of antagonists of specific beta-adrenergic receptor subtypes on bowel motility following abdominal surgery in rat model of postoperative ileus. Bowel motility was measured by the intestinal transit of Evans blue introduced via orogastric tube after surgical procedures of skin incision, laparotomy and laparotomy with gut manipulation. Male rats were given individual adrenergic receptor subtypes antagonists intraperitoneally, and the influence of administered agents on intestinal transit of Evans blue was then evaluated. No statistically significant differences in the length of intestine in tested rats were observed. Propranolol administered prior to surgical procedure has shown protective effect on Evans blue migration in rats undergoing laparotomy and gut manipulation. Intestinal dye transit for propranolol doses of 10, 30 and 45 mg/kg was 18.00 ± 1.88c m, 23.75 ± 1.71 cm and 22.5 ± 2.43 cm, respectively, and for last two doses, statistically significant increase of dye passage was noted, compared to Evans blue transit of 11.00 ± 2.43 cm in the control group. No acceleration of dye migration was seen following administration of beta1-, beta2- and beta3-selective adrenergic receptor antagonist metoprolol, ICI 118.551 and SR58894A, respectively. Our research confirmed that propranolol at high doses, as seen by other researchers, improved bowel motility in early phase of postoperative ileus. That slight acceleration of intestinal dye transit after surgery with gut manipulation is rather connected with membrane-stabilizing action, than the receptor blocking effect, as this effect was not observed after the application of selective antagonists of respective subtypes of beta-adrenergic receptor.

Novel Properties of Old Propranolol-Assessment of Antiglycation Activity through In Vitro and In Silico Approaches

Hypertension has earned the "silent killer" nickname since it may lead to a number of comorbidities, including diabetes and cardiovascular diseases. Oxidative stress and protein glycation play vital roles in the pathogenesis of hypertension. Several studies have shown that they profoundly account for vascular dysfunction, endothelial damage, and disruption of blood pressure regulatory mechanisms. Of particular note are advanced glycation end products (AGEs). AGEs alter vascular tissues' functional and mechanical properties by binding to receptors for advanced glycation end products (RAGE), stimulating inflammation and free radical-mediated pathways. Propranolol, a nonselective beta-adrenergic receptor antagonist, is one of the most commonly used drugs to treat hypertension and cardiovascular diseases. Our study is the first to analyze propranolol's effects on protein glycoxidation through in vitro and in silico approaches. Bovine serum albumin (BSA) was utilized to evaluate glycoxidation inhibition by propranolol. Propranolol (1 mM) and BSA (0.09 mM) were incubated with different glycating (0.5 M glucose, fructose, and galactose for 6 days and 2.5 mM glyoxal and methylglyoxal for 12 h) or oxidizing agents (chloramine T for 1 h). Biomarkers of protein glycation (Amadori products (APs), β-amyloid (βA), and advanced glycation end products (AGEs)), protein glycoxidation (dityrosine (DT), kynurenine (KYN), and N-formylkynurenine (NFK)), protein oxidation (protein carbonyls (PCs), and advanced oxidation protein products (AOPPs)) were measured by means of colorimetric and fluorimetric methods. The scavenging of reactive oxygen species (hydrogen peroxide, hydroxyl radical, and nitric oxide) and the antioxidant capacity (2,2-diphenyl-1-picrylhydrazyl radical and ferrous ion chelating (FIC) assays)) of propranolol were also evaluated. Additionally, in silico docking was performed to showcase propranolol's interaction with BSA, glycosides, and AGE/RAGE pathway proteins. The products of protein glycation (↓APs, ↓βA, ↓AGEs), glycoxidation (↓DT, ↓KYN, ↓NFK), and oxidation (↓PCs, ↓AOPPs) prominently decreased in the BSA samples with both glycating/oxidizing factors and propranolol. The antiglycoxidant properties of propranolol were similar to those of aminoguanidine, a known protein oxidation inhibitor, and captopril, which is an established antioxidant. Propranolol showed a potent antioxidant activity in the FIC and H2O2 scavenging assays, comparable to aminoguanidine and captopril. In silico analysis indicated propranolol's antiglycative properties during its interaction with BSA, glycosidases, and AGE/RAGE pathway proteins. Our results confirm that propranolol may decrease protein oxidation and glycoxidation in vitro. Additional studies on human and animal models are vital for in vivo verification of propranolol's antiglycation activity, as this discovery might hold the key to the prevention of diabetic complications among cardiology-burdened patients.

An enantioselective study of β-cyclodextrin and ionic liquid-β-cyclodextrin towards propranolol enantiomers by molecular dynamic simulations

In this study, the enantioselectivity of β-cyclodextrin and its derivatives towards propranolol enantiomers are investigated by molecular dynamic (MD) simulations. β-cyclodextrin (β-CD) have previously been shown to be able to recognize propranolol (PRP) enantiomers. To improve upon the enantioselectivity of β-cyclodextrin, we propose the use of an ionic-liquid-modified-β-cyclodextrin (β-CD-IL). β-CD-IL was found to be able to complex R and S propranolol enantiomers with differing binding energies. The molecular docking study reveals that the ionic liquid chain attached to the β-CD molecule has significant interaction with propranolol. The formation of the most stable complex occurred between (S)-β-CD-IL and (S)-propranolol with an energy of -5.80 kcal/mol. This is attributed to the formation of a hydrogen bond between the oxygen of the propranolol and the hydrogen on the primary rim of the (S)-β-CD-IL cavity. This interaction is not detected in other complexes. The root mean-squared fluctuation (RMSF) value indicates that the NH group is the most flexible molecular fragment, followed by the aromatic group. Also of note, the formation of a complex between pristine β-CD and (S)-propranolol is the least favorable.

Liposomal propranolol for treatment of infantile hemangioma at compounding pharmacies

Infantile hemangiomas (IH) are common benign soft tissue tumors, frequently affecting infants. While Propranolol Hydrochloride (Pro HCl) has emerged as a promising treatment for IH, its topical application remains challenging due to the need for stable and efficacious carriers. This study investigates the potential of preformulated liposomes as carriers for topical delivery of Pro HCl for the treatment of IH in compounding pharmacies. Liposomes loaded with Pro HCl were prepared using active pharmaceutical ingredient or commercially available propranolol tablets and various dilution media, including Water for Injection (WFI), Dextrose 5%, and NaCl 0.9%. The physicochemical properties of the liposomal formulations (Pro HCl content, encapsulation efficiency, loading capacity, and colloidal stability) were assessed over a 90-day storage at 4 °C. In vitro release kinetics and transdermal permeation of Pro HCl from liposomes were also evaluated. Liposome properties were influenced by the dilution medium. Pro HCl content remained stable in liposomes encapsulating API (Lipo-Pro), regardless of the dilution medium. Lipo-Pro showed sustained drug release over time, suggesting its potential for maintaining therapeutic levels. Pro HCl exhibited enhanced transdermal permeability from Lipo-Pro compared to aqueous solution, indicating its potential for topical IH treatment. Preformulated liposomes offer a stable and effective carrier for Pro HCl, potentially suitable for extemporaneous preparations in compounding pharmacies. Their enhanced transdermal permeability presents a promising alternative for topical IH treatment. This study provides valuable insights into the development of innovative and effective drug delivery strategies for managing IH, with future research focusing on in vivo applications and therapeutic potential.

The Anti-Virulence Activities of the Antihypertensive Drug Propranolol in Light of Its Anti-Quorum Sensing Effects against Pseudomonas aeruginosa and Serratia marcescens

The development of bacterial resistance is an increasing global concern that requires discovering new antibacterial agents and strategies. Bacterial quorum sensing (QS) systems play important roles in controlling bacterial virulence, and their targeting could lead to diminishing bacterial pathogenesis. In this context, targeting QS systems without significant influence on bacterial growth is assumed as a promising strategy to overcome resistance development. This study aimed at evaluating the anti-QS and anti-virulence activities of the β-adrenoreceptor antagonist propranolol at sub-minimal inhibitory concentrations (sub-MIC) against two Gram-negative bacterial models Pseudomonas aeruginosa and Serratia marcescens. The effect of propranolol on the expression of QS-encoding genes was evaluated. Additionally, the affinity of propranolol to QS receptors was virtually attested. The influence of propranolol at sub-MIC on biofilm formation, motility, and production of virulent factors was conducted. The outcomes of the propranolol combination with different antibiotics were assessed. Finally, the in vivo protection assay in mice was performed to assess propranolol's effect on lessening the bacterial pathogenesis. The current findings emphasized the significant ability of propranolol at sub-MIC to reduce the formation of biofilms, motility, and production of virulence factors. In addition, propranolol at sub-MIC decreased the capacity of tested bacteria to induce pathogenesis in mice. Furthermore, propranolol significantly downregulated the QS-encoding genes and showed significant affinity to QS receptors. Finally, propranolol at sub-MIC synergistically decreased the MICs of different antibiotics against tested bacteria. In conclusion, propranolol might serve as a plausible adjuvant therapy with antibiotics for the treatment of serious bacterial infections after further pharmacological and pharmaceutical studies.

Glucuronidation Pathways of 5- and 7-Hydroxypropranolol: Determination of Glucuronide Structures and Enzyme Selectivity

Propranolol, a non-selective beta-blocker medication, has been utilized in the treatment of cardiovascular diseases for several decades. Its hydroxynaphthyl metabolites have been recognized to possess varying degrees of beta-blocker activity due to the unaltered side-chain. This study achieved the successful separation and identification of diastereomeric glucuronic metabolites derived from 4-, 5-, and 7-hydroxypropranolol (4-OHP, 5-OHP, and 7-OHP) in human urine. Subsequently, reaction phenotyping of 5- and 7-hydroxypropranolol by different uridine 5'-diphospho-glucuronosyltransferases (UGTs) was carried out, with a comparison to the glucuronidation of 4-hydroxypropranolol (4-OHP). Among the 19 UGT enzymes examined, UGT1A1, UGT1A3, UGT1A7, UGT1A8, UGT1A9, UGT1A10, UGT2A1, and UGT2A2 were found to be involved in the glucuronidation of 5-OHP. Furthermore, UGT1A6 exhibited glucuronidation activity towards 7-OHP, along with the aforementioned eight UGTs. Results obtained by glucuronidation of corresponding methoxypropranolols and MS/MS analysis of 1,2-dimethylimidazole-4-sulfonyl (DMIS) derivatives of hydroxypropranolol glucuronides suggest that both the aromatic and aliphatic hydroxy groups of the hydroxypropranolols may be glucuronidated in vitro. However, the analysis of human urine samples collected after the administration of propranolol leads us to conclude that aromatic-linked glucuronidation is the preferred pathway under physiological conditions.

Role of K+ and Ca2+ Channels in the Vasodilator Effects of Plectranthus barbatus (Brazilian Boldo) in Hypertensive Rats

Plectranthus barbatus, popularly known as Brazilian boldo, is used in Brazilian folk medicine to treat cardiovascular disorders including hypertension. This study investigated the chemical profile by UFLC-DAD-MS and the relaxant effect by using an isolated organ bath of the hydroethanolic extract of P. barbatus (HEPB) leaves on the aorta of spontaneously hypertensive rats (SHR). A total of nineteen compounds were annotated from HEPB, and the main metabolite classes found were flavonoids, diterpenoids, cinnamic acid derivatives, and organic acids. The HEPB promoted an endothelium-dependent vasodilator effect (~100%; EC50 ~347.10 μg/mL). Incubation of L-NAME (a nonselective nitric oxide synthase inhibitor; EC50 ~417.20 μg/mL), ODQ (a selective inhibitor of the soluble guanylate cyclase enzyme; EC50 ~426.00 μg/mL), propranolol (a nonselective α-adrenergic receptor antagonist; EC50 ~448.90 μg/mL), or indomethacin (a nonselective cyclooxygenase enzyme inhibitor; EC50 ~398.70 μg/mL) could not significantly affect the relaxation evoked by HEPB. However, in the presence of atropine (a nonselective muscarinic receptor antagonist), there was a slight reduction in its vasorelaxant effect (EC50 ~476.40 μg/mL). The addition of tetraethylammonium (a blocker of Ca2+-activated K+ channels; EC50 ~611.60 μg/mL) or 4-aminopyridine (a voltage-dependent K+ channel blocker; EC50 ~380.50 μg/mL) significantly reduced the relaxation effect of the extract without the interference of glibenclamide (an ATP-sensitive K+ channel blocker; EC50 ~344.60 μg/mL) or barium chloride (an influx rectifying K+ channel blocker; EC50 ~360.80 μg/mL). The extract inhibited the contractile response against phenylephrine, CaCl2, KCl, or caffeine, similar to the results obtained with nifedipine (voltage-dependent calcium channel blocker). Together, the HEPB showed a vasorelaxant effect on the thoracic aorta of SHR, exclusively dependent on the endothelium with the participation of muscarinic receptors and K+ and Ca2+ channels.

Combination Therapy as a Promising Way to Fight Oral Cancer

Oral cancer is a highly aggressive tumor with invasive properties that can lead to metastasis and high mortality rates. Conventional treatment strategies, such as surgery, chemotherapy, and radiation therapy, alone or in combination, are associated with significant side effects. Currently, combination therapy has become the standard practice for the treatment of locally advanced oral cancer, emerging as an effective approach in improving outcomes. In this review, we present an in-depth analysis of the current advancements in combination therapies for oral cancer. The review explores the current therapeutic options and highlights the limitations of monotherapy approaches. It then focuses on combinatorial approaches that target microtubules, as well as various signaling pathway components implicated in oral cancer progression, namely, DNA repair players, the epidermal growth factor receptor, cyclin-dependent kinases, epigenetic readers, and immune checkpoint proteins. The review discusses the rationale behind combining different agents and examines the preclinical and clinical evidence supporting the effectiveness of these combinations, emphasizing their ability to enhance treatment response and overcome drug resistance. Challenges and limitations associated with combination therapy are discussed, including potential toxicity and the need for personalized treatment approaches. A future perspective is also provided to highlight the existing challenges and possible resolutions toward the clinical translation of current oral cancer therapies.

Migraine, Allergy, and Histamine: Is There a Link?

The relationship between migraines and allergies is controversial. Though they are epidemiologically linked, the underlying pathophysiological connection between them remains unclear. Migraines and allergic disorders have various underlying genetic and biological causes. As per the literature, these conditions are epidemiologically linked, and some common pathophysiological pathways have been hypothesized. The histaminergic system may be the clue to understanding the correlation among these diseases. As a neurotransmitter in the central nervous system with a vasodilatory effect, histamine has a well-documented influence on the allergic response and could be involved in the pathophysiology of migraines. Histamine may influence hypothalamic activity, which may play a major role in migraines or may simply influence their severity. In both cases, antihistamine drugs could prove useful. This review examines whether the histaminergic system, particularly H3 and H4 receptors, may provide a mechanistic link between the pathophysiology of migraines and allergic disorders, two common and debilitating conditions. Identifying their connection could help identify novel therapeutic strategies.

Acute Cardiovascular and Cardiorespiratory Effects of JWH-018 in Awake and Freely Moving Mice: Mechanism of Action and Possible Antidotal Interventions?

JWH-018 is the most known compound among synthetic cannabinoids (SCs) used for their psychoactive effects. SCs-based products are responsible for several intoxications in humans. Cardiac toxicity is among the main side effects observed in emergency departments: SCs intake induces harmful effects such as hypertension, tachycardia, chest pain, arrhythmias, myocardial infarction, breathing impairment, and dyspnea. This study aims to investigate how cardio-respiratory and vascular JWH-018 (6 mg/kg) responses can be modulated by antidotes already in clinical use. The tested antidotes are amiodarone (5 mg/kg), atropine (5 mg/kg), nifedipine (1 mg/kg), and propranolol (2 mg/kg). The detection of heart rate, breath rate, arterial oxygen saturation (SpO2), and pulse distention are provided by a non-invasive apparatus (Mouse Ox Plus) in awake and freely moving CD-1 male mice. Tachyarrhythmia events are also evaluated. Results show that while all tested antidotes reduce tachycardia and tachyarrhythmic events and improve breathing functions, only atropine completely reverts the heart rate and pulse distension. These data may suggest that cardiorespiratory mechanisms of JWH-018-induced tachyarrhythmia involve sympathetic, cholinergic, and ion channel modulation. Current findings also provide valuable impetus to identify potential antidotal intervention to support physicians in the treatment of intoxicated patients in emergency clinical settings.

Beta-adrenergic receptor blocker propranolol triggers anti-tumor immunity and enhances irinotecan therapy in mice colorectal cancer

Colorectal cancer (CRC) stands as the second leading cause of cancer-related deaths worldwide with limited available medicines. While drug repurposing comes as a promising strategy for cancer treatment, we discovered that propranolol (Prop), a non-selective β1 and β2 adrenergic receptor blocker, significantly inhibited the development of subcutaneous CT26 CRC and AOM/DSS-induced CRC models. The RNA-seq analysis highlighted the activated immune pathways after Prop treatment, with GO analysis enriched in T-cell differentiation, leukocyte-mediated immunity, regulation of leukocyte-mediated cytotoxicity, and interferon-gamma production. Routine analyses of blood revealed a decrease in neutrophil to lymphocyte ratio, a biomarker of systemic inflammation, and a prognostic indicator in the Prop-treated groups in both CRC models. Analysis of the tumor-infiltrating immune cells exhibited that Prop regressed the exhaustion of CD4⁺ and CD8⁺ T cells in the CT26-derived graft models, which was further corroborated in the AOM/DSS-induced models. Furthermore, bioinformatic analysis fitted well with the experimental data, showing that β2 adrenergic receptor (ADRB2) was positively correlated with T-cell exhaustion signature in various tumors. The in vitro experiment showed no direct effect of Prop on CT26 cell viability, while T cells were activated with significantly-upregulated production of IFN-γ and Granzyme B. Consistently, Prop was unable to restrain CT26 tumor growth in nude mice. At last, the combination of Prop and the chemotherapeutic drug Irinotecan acted out the strongest inhibition in CT26 tumor progress. Collectively, we repurpose Prop as a promising and economical therapeutic drug for CRC treatment and highlight T-cell as its target.

Synthesis, Chiral Resolution and Enantiomers Absolute Configuration of 4-Nitropropranolol and 7-Nitropropranolol

We recently identified 6-nitrodopamine and other nitro-catecholamines (6-nitrodopa, 6-nitroadrenaline), indicating that the endothelium has the ability to nitrate the classical catecholamines (dopamine, noradrenaline, and adrenaline). In order to investigate whether drugs could be subject to the same nitration process, we synthesized 4-nitro- and 7-nitropropranolol as probes to evaluate the possible nitration of the propranolol by the endothelium. The separation of the enantiomers in very high yields and excellent enantiopurity was achieved by chiral HPLC. Finally, we used Riguera's method to determine the absolute configuration of the enantiomers, through double derivatization with MPA and NMR studies.

Migraine Pharmacological Treatment and Cognitive Impairment: Risks and Benefits

Migraine is a common neurological disorder impairing the quality of life of patients. The condition requires, as an acute or prophylactic line of intervention, the frequent use of drugs acting on the central nervous system (CNS). The long-term impact of these medications on cognition and neurodegeneration has never been consistently assessed. The paper reviews pharmacological migraine treatments and discusses their biological and clinical effects on the CNS. The different anti-migraine drugs show distinct profiles concerning neurodegeneration and the risk of cognitive deficits. These features should be carefully evaluated when prescribing a pharmacological treatment as many migraineurs are of scholar or working age and their performances may be affected by drug misuse. Thus, a reconsideration of therapy guidelines is warranted. Furthermore, since conflicting results have emerged in the relationship between migraine and dementia, future studies must consider present and past pharmacological regimens as potential confounding factors.

A murine model of cerebral cavernous malformations with acute hemorrhage

Cavernomas are multi-lumen and blood-filled vascular malformations which form in the brain and the spinal cord. They lead to hemorrhage, epileptic seizures, neurological deficits, and paresthesia. An effective medical treatment is still lacking, and the available murine models for cavernomas have several limitations for preclinical studies. These include disease phenotypes that differ from human diseases, such as restriction of the lesions to the cerebellum, and absence of acute hemorrhage. Additional limitations of current murine models include rapid development of lesions, which are lethal before the first month of age. Here, we have characterized a murine model that recapitulates features of the human disease: lesions develop after weaning throughout the entire CNS, including the spinal cord, and undergo acute hemorrhage. This provides a preclinical model to develop new drugs for treatment of acute hemorrhage in the brain and spinal cord, as an unmet medical emergency for patients with cavernomas.

Ccm3 deletion in endothelial progenitors drives cavernoma formation in a mouse model

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Mice develop acute hemorrhage and inflammation in brain and spinal cord

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The spleen has increased vascular density and altered hemopoiesis

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This model represents a useful tool for mechanistic studies and drug screening

Acute effect of propranolol on resting energy expenditure in hyperthyroid patients

OBJECTIVE

Hyperthyroidism is a common endocrine disorder which leads to higher resting energy expenditure (REE). Increased activity of brown adipose tissue (BAT) contributes to elevated REE in hyperthyroid patients. For rapid control of hyperthyroid symptoms, the non-selective β-blocker propranolol is widely used. While, long-term treatment with propranolol reduces REE it is currently unclear whether it can also acutely diminish REE.

DESIGN

In the present prospective interventional trial we investigated the effect of propranolol on REE in hyperthyroid patients.

METHODS

Nineteen patients with overt primary hyperthyroidism were recruited from the endocrine outpatient clinic. REE was measured by indirect calorimetry before and after an acute dose of 80mg propranolol and during a control period, respectively. Additionally, skin temperature was recorded at eleven predefined locations during each study visit, vital signes and heart rate (HR) were measured before and after administration of propranolol.

RESULTS

Mean REE decreased slightly after acute administration of 80mg propranolol (p= 0.03) from 1639 ± 307 kcal/24h to 1594 ± 283 kcal/24h. During the control visit REE did not change significantly. HR correlated significantly with the level of free T3 (R² = 0.38, p=0.029) free T4 (R² = 0.39, p=0.026). HR decreased 81 ± 12 bpm to 67 ± 7.6 bpm 90 minutes after oral administration of propranolol (p<0.0001). Skin temperature did not change after propranolol intake.

CONCLUSIONS

In hyperthyroid patients a single dose of propranolol reduced heart rate substantially but REE diminished only marginally probably due to reduced myocardial energy consumption. Our data speak against a relevant contribution of BAT to the higher REE in hyperthyroidism.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, identifier (NCT03379181).

A Novel Voltametric Measurements of Beta Blocker Drug Propranolol on Glassy Carbon Electrode Modified with Carbon Black Nanoparticles

A new voltametric method for highly sensitive propranolol (PROP) determination was developed. A glassy carbon electrode modified with a hybrid material made of carbon black (CB) and Nafion was used as the working electrode. The preconcentration potential and time were optimized (550 mV and 15 s), as well as the supporting electrolyte (0.1 mol L⁻¹ H₂SO₄). For 15 s preconcentration time, linearity was achieved in the range 0.5–3.5 μmol L⁻¹ and for 120 s in 0.02–0.14 μmol L⁻¹. Based on the conducted calibration (120 s preconcentration time) limit of detection (LOD) was calculated and was equal to 7 nmol L⁻¹. To verify the usefulness of the developed method, propranolol determination was carried out in real samples (tablets and freeze-dried urine). Recoveries were calculated and were in the range 92–102%, suggesting that the method might be considered as accurate. The repeatability of the signal expressed as relative standard deviation (RSD) was equal to 1.5% (n = 9, PROP concentration 2.5 µmol L⁻¹). The obtained results proved that the developed method for propranolol determination might be successfully applied in routine laboratory practice.

Improvement in epistaxis management: the experience of a dedicated hereditary haemorrhagic telangiectasia clinic

BACKGROUND

Hereditary haemorrhagic telangiectasia (HHT) is a rare genetic vascular disorder which is characterised by the development of arteriovenous malformations and telangiectasias. A key clinical manifestation is recurrent epistaxis. This study examined the impact of a dedicated HHT clinic in a major Australian tertiary hospital on epistaxis symptoms and subjective quality of life.

METHODS

A multidisciplinary HHT clinic was established in 2015. All patients satisfied either genetic diagnosis or fulfilled Curacao criteria. A protocol based clinical assessment was performed and a standardised treatment regimen was implemented. Patients completed quality of life and epistaxis severity score (ESS) questionnaires at each review.

RESULTS

Participants of the dedicated clinic included 21 females (58.3%) and 15 males (41.7%), with a mean age of 49.0 ± 24.0 years. The ACVRL1 variant was the most common (n = 20, 55.6%). A statistically significant reduction in epistaxis severity was noted between the baseline and second review (P = 0.02) and was maintained to the third visit (P = 0.015). Patients older than 50 years demonstrate a consistently higher ESS than those less than 50 years old (P = 0.03). This trend is noted throughout the follow up period with the dedicated clinic.

CONCLUSION

The introduction of a multidisciplinary, dedicated HHT clinic to provide enhanced assessment, monitored treatment regimen and greater access to care, resulted in improvement in the management of epistaxis and quality of life in these patients.

Betulinic Acid Improves Cardiac-Renal Dysfunction Caused by Hypertrophy through Calcineurin-NFATc3 Signaling

Cardiac hypertrophy can lead to congestive heart failure and is a leading cause of morbidity and mortality worldwide. In recent years, it has been essential to find the treatment and prevention of cardiac hypertrophy. Betulinic acid (BA), the main active ingredient in many natural products, is known to have various physiological effects. However, as the potential effect of BA on cardiac hypertrophy and consequent renal dysfunction is unknown, we investigated the effect of BA on isoprenaline (ISO)-induced cardiac hypertrophy and related signaling. ISO was known to induce left ventricular hypertrophy by stimulating the β2-adrenergic receptor (β2AR). ISO was injected into Sprague Dawley rats (SD rats) by intraperitoneal injection once a day for 28 days to induce cardiac hypertrophy. From the 14th day onwards, the BA (10 or 30 mg/kg/day) and propranolol (10 mg/kg/day) were administered orally. The study was conducted in a total of 5 groups, as follows: C, control; Is, ISO (10 mg/kg/day); Pr, positive-control, ISO + propranolol (10 mg/kg/day); Bl, ISO + BA (10 mg/kg/day); Bh, ISO + BA (30 mg/kg/day). As a result, the total cardiac tissue and left ventricular tissue weights of the ISO group increased compared to the control group and were significantly reduced by BA treatment. In addition, as a result of echocardiography, the effect of BA on improving cardiac function, deteriorated by ISO, was confirmed. Cardiac hypertrophy biomarkers such as β-MHC, ANP, BNP, LDH, and CK-MB, which were increased by ISO, were significantly decreased by BA treatment. Also, the cardiac function improvement effect of BA was confirmed to improve cardiac function by inhibiting calcineurin/NFATc3 signaling. Renal dysfunction is a typical complication caused by cardiac hypertrophy. Therefore, the study of renal function indicators, creatinine clearance (Ccr) and osmolality (BUN) was aggravated by ISO treatment but was significantly restored by BA treatment. Therefore, it is thought that BA in cardiac hypertrophy can be used as valuable data to develop as a functional material effective in improving cardiac-renal dysfunction.

Metoprolol decreases retention of fear memory and facilitates long-term depression in lateral amygdala

Posttraumatic stress disorder is a mental disorder with a known cause, yet effective behavioral and pharmacotherapies remain elusive for many afflicted patients. Propranolol is suggested to be effective as a fear-reducing agent when paired with behavioral therapy soon after trauma when psychological stress is high, possibly dampening or preventing the later development of posttraumatic stress disorder. In our previous study, we found propranolol efficaciously reduced fear retention induced by reactivation via β-adrenergic receptors in lateral amygdala. However, it is unclear which subtypes of β-adrenergic receptors dominate the function of adrenergic activation in lateral amygdala. In this study, we investigated the action of β1-adrenergic receptor antagonist-metoprolol and β2-adrenergic receptor antagonist-butoxamine on the retention of conditioned fear memory and synaptic adaptation in the lateral amygdala of rats. We found metoprolol not butoxamine attenuated the reactivation-induced strengthening of fear retention and restored the impaired long-term depression in lateral amygdala. Intra-amygdala infusion of metoprolol not butoxamine attenuated reactivation-induced enhancement of fear retention. Our results suggest that β1-adrenergic receptor antagonist-metoprolol may be more suitable for the treatment of posttraumatic stress disorder.

Neurobiology of Cancer: Introduction of New Drugs in the Treatment and Prevention of Cancer

Research on the neurobiology of cancer, which lies at the border of neuroscience and oncology, has elucidated the mechanisms and pathways that enable the nervous system to modulate processes associated with cancer initiation and progression. This research has also shown that several drugs which modulate interactions between the nervous system and the tumor micro- and macroenvironments significantly reduced the progression of cancer in animal models. Encouraging results were also provided by prospective clinical trials investigating the effect of drugs that reduce adrenergic signaling on the course of cancer in oncological patients. Moreover, it has been shown that reducing adrenergic signaling might also reduce the incidence of cancer in animal models, as well as in humans. However, even if many experimental and clinical findings have confirmed the preventive and therapeutic potential of drugs that reduce the stimulatory effect of the nervous system on processes related to cancer initiation and progression, several questions remain unanswered. Therefore, the aim of this review is to critically evaluate the efficiency of these drugs and to discuss questions that need to be answered before their introduction into conventional cancer treatment and prevention.

The Activation of Endothelial Cells Relies on a Ferroptosis-Like Mechanism: Novel Perspectives in Management of Angiogenesis and Cancer Therapy

The activation of endothelial cells (ECs) is a crucial step on the road map of tumor angiogenesis and expanding evidence indicates that a pro-oxidant tumor microenvironment, conditioned by cancer metabolic rewiring, is a relevant controller of this process. Herein, we investigated the contribution of oxidative stress-induced ferroptosis to ECs activation. Moreover, we also addressed the anti-angiogenic effect of Propranolol. We observed that a ferroptosis-like mechanism, induced by xCT inhibition with Erastin, at a non-lethal level, promoted features of ECs activation, such as proliferation, migration and vessel-like structures formation, concomitantly with the depletion of reduced glutathione (GSH) and increased levels of oxidative stress and lipid peroxides. Additionally, this ferroptosis-like mechanism promoted vascular endothelial cadherin (VE-cadherin) junctional gaps and potentiated cancer cell adhesion to ECs and transendothelial migration. Propranolol was able to revert Erastin-dependent activation of ECs and increased levels of hydrogen sulfide (H₂S) underlie the mechanism of action of Propranolol. Furthermore, we tested a dual-effect therapy by promoting ECs stability with Propranolol and boosting oxidative stress to induce cancer cell death with a nanoformulation comprising selenium-containing chrysin (SeChry) encapsulated in a fourth generation polyurea dendrimer (SeChry@PURE_G4). Our data showed that novel developments in cancer treatment may rely on multi-targeting strategies focusing on nanoformulations for a safer induction of cancer cell death, taking advantage of tumor vasculature stabilization.

Effectiveness of drugs acting on adrenergic receptors in the treatment for tobacco or alcohol use disorders: systematic review and meta-analysis

AIM

To assess the efficacy of drugs directly acting on alpha- and beta-adrenergic receptors in the treatment of patients suffering from tobacco or alcohol use disorder.

METHODS

Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, studies were identified through PUBMED, EMBASE, the Cochrane Central Register of Controlled Trials and clinicaltrial.gov. We selected only randomized controlled trials with adult patients with tobacco or alcohol use disorders according to DSM-5 criteria. Interventions included any molecule having a direct pharmacological action on alpha- or beta-adrenergic receptors (agonist or antagonist). Comparators were placebo or other validated pharmacotherapies. The duration of the intervention was a minimum of 1 month, with 3 months of follow-up. Measurements included smoking cessation for tobacco; for alcohol, we selected abstinence, alcohol consumption (drinks per day or week) and heavy drinking days (HDD). Ten studies with tobacco and six with alcohol use disorder were included in the qualitative synthesis and fifteen studies in the quantitative analysis.

RESULTS

We found that clonidine, an alpha-2 agonist, significantly increased smoking abstinence [relative risk = 1.39 with a 95% confidence interval (CI) = 1.04, 1.84]. Beta-blockers had no significant effect on smoking abstinence. The alpha-1 antagonists prazosin and doxazosin decreased alcohol consumption [SMD = -0.32 (-0.56, -0.07)] but had no effect on abstinence or HDD.

CONCLUSIONS

The noradrenaline system may represent a promising mechanism to target in tobacco and alcohol use disorders.

Design and Evaluation of Dissolving Microneedles for Enhanced Dermal Delivery of Propranolol Hydrochloride

Oral propranolol hydrochloride has been the first-line treatment for infantile hemangioma (IH), whereas systemic exposure to propranolol has the potential of causing serious adverse reactions. Dermal delivery of propranolol is preferable due to high local drug concentration and fewer adverse effects. However, propranolol hydrochloride (BCS class I) is highly hydrophilic and has difficulty in penetrating the stratum corneum (SC) barrier. Dissolving microneedles (MNs) are an efficient tool for overcoming the barrier of the SC and enhancing dermal drug delivery. In this study, propranolol hydrochloride-loaded dissolving MNs were fabricated by using hyaluronic acid and polyvinyl pyrrolidone as matrix materials. Controllable drug loading in needle tips was achieved by a two-step casting procedure. The needles were good in mechanical strength for penetrating the SC while presented excellent dissolving capability for releasing propranolol hydrochloride. In comparison with the solution counterpart, irrespective of being applied to intact skin or solid MNs-pretreated skin, dissolving MNs significantly increased the permeability and skin retention of propranolol. In conclusion, dissolving MNs could be a potential approach for enhancing dermal delivery of propranolol to treat IH.

Propranolol Reduces the Development of Lesions and Rescues Barrier Function in Cerebral Cavernous Malformations: A Preclinical Study

[Figure: see text].

Clinical Pharmacokinetics of Propranolol Hydrochloride: A Review

BACKGROUND

Nobel laureate Sir James Black's molecule, propranolol, still has broad potential in cardiovascular diseases, infantile haemangiomas and anxiety. A comprehensive and systematic review of the literature for the summarization of pharmacokinetic parameters would be effective to explore the new safe uses of propranolol in different scenarios, without exposing humans and using virtual-human modeling approaches.

OBJECTIVE

This review encompasses physicochemical properties, pharmacokinetics and drug-drug interaction data of propranolol collected from various studies.

METHODS

Clinical pharmacokinetic studies on propranolol were screened using Medline and Google Scholar databases. Eighty-three clinical trials, in which pharmacokinetic profiles and plasma time concentration were available after oral or IV administration, were included in the review.

RESULTS

The study depicts that propranolol is well absorbed after oral administration. It has dose-dependent bioavailability, and a 2-fold increase in dose results in a 2.5-fold increase in the area under the curve, a 1.3-fold increase in the time to reach maximum plasma concentration and finally, 2.2 and 1.8-fold increase in maximum plasma concentration in both immediate and long-acting formulations, respectively. Propranolol is a substrate of CYP2D6, CYP1A2 and CYP2C19, retaining potential pharmacokinetic interactions with co-administered drugs. Age, gender, race and ethnicity do not alter its pharmacokinetics. However, in renal and hepatic impairment, it needs a dose adjustment.

CONCLUSION

Physiochemical and pooled pharmacokinetic parameters of propranolol are beneficial to establish physiologically based pharmacokinetic modeling among the diseased population.

Propranolol induced apoptosis and autophagy via the ROS/JNK signaling pathway in Human Ovarian Cancer

Propranolol has a significant anti-cancer effect towards various cancers. Our study aimed at investigating the underlying mechanism of Propranolol's therapeutic effect towards ovarian cancer. Specifically, Propranolol significantly reduced the viability of human ovarian cancer cell lines SKOV-3 and A2780 in a dose- and time-dependent manner. Flow cytometry analysis revealed that Propranolol induced the cell cycle arrest at G2/M phase therefore leading to apoptosis. Moreover, autophagy inhibitor 3-MA markedly enhanced the Propranolol-induced apoptosis. In addition, reactive oxygen species (ROS) increased dramatically after Propranolol treatment and Propranolol activated the phosphorylation of JNK. What is more, p38 inhibitor SB203580 and JNK inhibitor SP600125 attenuated the upregulated expression of LC3-II and cleaved-caspase-3 by the effect of Propranolol. ROS exclusive inhibitor antioxidant N-acetyl cysteine (NAC) weakens the phosphorylation of JNK proteins induced by Propranolol. In summary, these results suggested that Propranolol induced cell apoptosis and protective autophagy through the ROS/JNK signaling pathway in human ovarian cancer cells.

Negative Inotropic Effect of BGP-15 on the Human Right Atrial Myocardium

Cardiovascular morbidity and mortality carry great socioeconomic burden worldwide that mandates the development of new, efficacious therapeutic agents with limited adverse effects. O-(3-piperidino-2-hydroxy-1-propyl) nicotinic acid amidoxime (BGP-15) is a known, well-tolerable drug candidate that exerts beneficial effects in several disease models. As BGP-15 has a significant structural similarity with propranolol, it arose that BGP-15 might also have a direct effect on the heart. Thus, in the present work, we investigated the effect of BGP-15 and propranolol on the contractility of isolated, paced, human right atrial samples (obtained from patients undergone open-heart surgery), with or without previous isoproterenol (ISO) stimulation (evoking an indirect or direct effect, respectively). We found that both BGP-15 and propranolol exerted direct as well as indirect negative inotropic effects on the atrial myocardium, reaching similar maximal response. However, BGP-15 had considerably smaller potency than propranolol regarding both types of negative inotropy. In addition, BGP-15, in contrast to propranolol, had a significantly greater indirect negative inotropic effect on samples exhibiting strong response to ISO. Moreover, the indirect negative inotropic effect of BGP-15 was significantly greater on samples derived from diabetic patients than on samples obtained from non-diabetic ones. Our results suggest that the enhanced ISO sensitivity is associated with the diabetic state, and BGP-15 exerts greater negative inotropic effect on the human atrial myocardium in both conditions (as compared to the atrial tissue that is not ISO oversensitive and/or diabetic). Additionally, the negative inotropic effects of BGP-15 and propranolol seem to be mediated by in part different molecular pathways in the atrial myocardium.

Removal of propranolol hydrochloride by batch biosorption using remaining biomass of alginate extraction from Sargassum filipendula algae

Propranolol hydrochloride is a popular anti-hypertensive and pollutant of emerging concern because of potential ecological risks to aquatic environment. In this study, biosorption is presented as an advanced approach for propranolol uptake from aqueous media. The remaining biomass of alginate extraction from brown seaweed (RSF) was tested as biosorbent owing to its key binding sites, namely carboxyl and hydroxyl functional groups. The high 93% removal efficiency achieved consolidates RSF as effective biosorbent for propranolol environmental remediation and values this waste material, which has been largely discarded in industry after alginate extraction. RSF had morphology, porosity, chemical composition, and thermal behavior characterized prior and post to application in propranolol biosorption. Molecular sieving effects were excluded by assessing the molecular geometry of propranolol. The kinetics was inspected by both rate laws and mass transfer models. Langmuir, Freundlich, and Dubinin-Radushkevich equations were tested for experimental isotherms. Propranolol biosorption onto RSF was further inspected by thermodynamic parameters, including isosteric heat.

Nonselective alpha-/beta- AR antagonists can inhibit pericyte proliferation, migration, and secretion in vitro

It has been reported that the beta-adrenergic receptor blocker (propranolol) and the a-adrenergic receptor (AR) blocker (phentolamine) both can inhibit human endothelial cell (EC) angiogenesis in vitro. However, it is unknown whether this inhibition also acts on pericytes. The present study aimed to determine how pericytes react to treatment with an a-/β- AR blocker. In the study, cell proliferation assays and scratch assay were performed to assess the effect of phentolamine or propranolol on cell proliferation and migration. Western blot and ELISA were employed to determine changes in VEGF-A and Ang-1 expression levels. The results indicated that the nonselective a-/β- AR blocker inhibited the proliferation, migration, and secretion of pericytes. The use of the nonselective a-/β- AR blocker might have an impact on vascularization and vascular maturation. Our research suggests the rational use of nonselective a-/β- AR blockers to treat angiogenesis-dependent diseases.

Beta-blockers and glioma: a systematic review of preclinical studies and clinical results

Given the median survival of 15 months after diagnosis, novel treatment strategies are needed for glioblastoma. Beta-blockers have been demonstrated to inhibit angiogenesis and tumor cell proliferation in various cancer types. The aim of this study was to systematically review the evidence on the effect of beta-blockers on glioma growth. A systematic literature search was performed in the PubMed, Embase, Google Scholar, Web of Science, and Cochrane Central to identify all relevant studies. Preclinical studies concerning the pharmacodynamic effects of beta-blockers on glioma growth and proliferation were included, as well as clinical studies that studied the effect of beta-blockers on patient outcomes according to PRISMA guidelines. Among the 980 citations, 10 preclinical studies and 1 clinical study were included after title/abstract and full-text screening. The following potential mechanisms were identified: reduction of glioma cell proliferation (n = 9), decrease of glioma cell migration (n = 2), increase of drug sensitivity (n = 1), induction of glioma cell death (n = 1). Beta-blockers affect glioma proliferation by inducing a brief reduction of cAMP and a temporary cell cycle arrest in vitro. Contrasting results were observed concerning glioma cell migration. The identified clinical study did not find an association between beta-blockers and survival in glioma patients. Although preclinical studies provide scarce evidence for the use of beta-blockers in glioma, they identified potential pathways for targeting glioma. Future studies are needed to clarify the effect of beta-blockers on clinical endpoints including survival outcomes in glioma patients to scrutinize the value of beta-blockers in glioma care.

The influence of adrenergic blockade in rats with apical periodontitis under chronic stress conditions

OBJECTIVE

To investigate the influence of chronic stress and adrenergic blockade in a rat model of apical periodontitis.

METHODS

Thirty-two Wistar rats were submitted to an animal model of periapical lesion and randomly divided into 4 groups (n = 8): no stress (NS); stress + saline solution (SS); stress + β-adrenergic blocker (Sβ); stress + α-adrenergic blocker (Sα). The SS, Sβ and Sα groups were submitted to an animal model of chronic stress for 28 days and received daily injections of saline solution, propranolol (β adrenergic blocker) and phentolamine (α adrenergic blocker), respectively. After 28 days the animals were euthanized and the following analyses were carried out: a) serum corticosterone levels through Radioimmunoassay; b) measurement of serum levels of IL-1B, IL-6, IL-10 and IL-17 by enzyme-linked immunosorbent assay (ELISA); c) volume of periapical bone resorption by micro-computed tomography; d) histomorphometric analysis by staining with hematoxylin and eosin; e) expression of β-AR, α-AR, receptor activator of nuclear factor kappa-B ligand (RANKL) and osteoprotegerin (OPG) by immunohistochemistry; f) tartrate-resistant acid phosphatase (TRAP) staining; g) ex-vivo cytokine release followed by the stimulation with LPS in superfusion system, by ELISA.

RESULTS

SS group displayed significantly higher corticosterone levels than NS group (non-stressed). Higher IL-1β serum level was observed in the NS group (p < .05); compared to all stressed groups. Other cytokines were present in similar amounts in the serum of all groups. All groups presented similar periapical lesions. All groups presented moderate inflammatory infiltrate, without statistically significant differences between them. No differences were observed regarding β-AR, α-AR, Rank-L and OPG expression. The number of TRAP-positive cells was significantly decreased in the groups that received daily injections of adrenergic blockers. The IL-1β release followed LPS stimulation was significantly suppressed when the superfusion media contained propranolol (p < .05). Perfusion containing phentolamine induced a greater release of IL-10. TGF-β was significantly suppressed by phentolamine perfusion in the NS group (p < .05).

CONCLUSIONS

Chronic stress can significantly change the inflammatory cytokines release. Rank-L/OPG system and periapical lesion volume were not affected following the current method applied. The administration of adrenergic blockers was not able to modulate the inflammatory response but presented effectivity in reducing the number of osteoclasts in the periapical region.

Identification of a α-helical molten globule intermediate and structural characterization of β-cardiotoxin, an all β-sheet protein isolated from the venom of Ophiophagus hannah (king cobra)

β-Cardiotoxin is a novel member of the snake venom three-finger toxin (3FTX) family. This is the first exogenous protein to antagonize β-adrenergic receptors and thereby causing reduction in heart rates (bradycardia) when administered into animals, unlike the conventional cardiotoxins as reported earlier. 3FTXs are stable all β-sheet peptides with 60-80 amino acid residues. Here, we describe the three-dimensional crystal structure of β-cardiotoxin together with the identification of a molten globule intermediate in the unfolding pathway of this protein. In spite of the overall structural similarity of this protein with conventional cardiotoxins, there are notable differences observed at the loop region and in the charge distribution on the surface, which are known to be critical for cytolytic activity of cardiotoxins. The molten globule intermediate state present in the thermal unfolding pathway of β-cardiotoxin was however not observed during the chemical denaturation of the protein. Interestingly, circular dichroism (CD) and NMR studies revealed the presence of α-helical secondary structure in the molten globule intermediate. These results point to substantial conformational plasticity of β-cardiotoxin, which might aid the protein in responding to the sometimes conflicting demands of structure, stability, and function during its biological lifetime.

Behavior and histopathology as biomarkers for evaluation of the effects of paracetamol and propranolol in the neotropical fish species Phalloceros harpagos

Pharmaceutical drugs in the aquatic environment can induce adverse effects on nontarget organisms. This study aimed to assess the short-term effects of sublethal concentrations of both paracetamol and propranolol on the fish Phalloceros harpagos, specifically light/dark preference, swimming patterns, skin pigmentation, histopathology, and liver glycogen levels. Fish were acutely exposed to sublethal concentrations of both paracetamol (0.008, 0.08, 0.8, 8, 80 mg L^-1) and propranolol (0.0001, 0.001, 0.01, 0.1, 1 mg L^-1) under controlled conditions. For scototaxis, a significant preference for the dark compartment was observed for the group exposed to the highest concentration of paracetamol (80 mg L^-1). Propranolol exposure significantly altered the swimming pattern, especially in fish exposed to the 0.001 mg L^-1 concentration. Pigmentation was reduced in propranolol-exposed fish (0.1, 1 mg L^-1). The lowest concentration of propranolol (0.0001 mg L^-1) induced a decrease of histochemical reaction for hepatic glycogen. These data demonstrate that pharmaceuticals can induce sublethal effects in nontarget organisms, even at low concentrations, compromising specific functions of the individual with ecological relevance, such as energy balance and behavior.

ClC-3 chloride channel is involved in isoprenaline-induced cardiac hypertrophy

Isoprenaline, an activator of β-adrenergic receptor, has been found to induce cardiac hypertrophy in vivo and in vitro, but the exact mechanism is still unclear. ClC-3 is a member of the chloride channel family and is highly expressed in mammalian myocardium. In the present study, the role of ClC-3 in isopronaline-induced cardiac hypertrophy was investigated. We found that ClC-3 expression was reduced in isoprenaline-induced hypertrophic H9c2 cells, primary rat neonatal cardiomyocytes and myocardium of C57/BL/6 mice, and this reduction was prevented by the pretreatment of propranolol. Adeno-associated virus 9 (AAV9)-mediated ClC-3 expression in myocardium decreased heart mass index, thinned interventricular septum and left ventricular wall and lowered the mRNA expression of natriuretic peptide type A (ANF) and β-myosin heavy chain (β-MHC). Our results showed that ClC-3 played an important role in β-adrenergic cardiac hypertrophy which could be associated with ANF and β-MHC, and all these findings suggested that ClC-3 may be a novel therapeutic target for the prevention or treatment of myocardiac hypertrophy.