Beta Adrenoreceptor Research Articles

6668 Myxedema Coma and Takotsubo Cardiomyopathy

Abstract Disclosure: A.M. Skariah: None. S. Jain: None. Background: Takotsubo cardiomyopathy (TCM) also know as broken heart syndrome is a transient decrease in systolic cardiac function in the absence of obstructive CAD. TCM is likely related to hyperadrenergic conditions leading to increased cardiac sensitivity to catecholamine surge leading to cardiomyopathy. TCM is more associated with hyperthyroidism. Case presentation: Patient is an 84-year-old female with PMH of celiac disease,hypertension,prediabetes, and atrial fibrillation s/p cardioversion, on amiodarone. She was brought to the ER after having an unwitnessed fall. She was hypotensive 76/56 mm of Hg, hypothermic 35.5 degree C, HR 90 beats/min; labs significant for hyponatremia, macrocytic anemia, TSH 65.47uIU/ml, FT4 <0.4 ng/dl and mild QTC prolongation of 469ms. Family mentioned history of constipation, progressive weakness, poor oral intake, memory problems and cold sensitivity for a couple of months. Started on 1 pressor, 3 units of PRBC and 2 liters of IVF; BP improved; labs and history suggestive of myxedema coma with myxedema coma Popoveniuc score 85 suggestive of high suspicion for myxedema coma.She had TSH 50.39 uIU/ml and FT4 of 0.4 ng/dl for her memory issues workup 2 months prior to presentation but was not started on medication. Upon admission, started stress dose steroids followed by IV levothyroxine 100 mcg. Not started on LT3 given her old age and atrial fibrillation history. Received additional dose of LT4 100 mcg within few hours. TFT improved with TSH 35 uIU/ml and FT4 1 ng/dl after 2 doses. Later same day, shock worsened, and patient was on 3 pressors along with stress dose of steroids. Cardiology was consulted; recommended an Echocardiogram.Echo was done on day 2; EF 55-60 % with severe hypokinesis of apical myocardium consistent with TCM. Normal echocardiogram studies 4 months ago.Started on weight-based regimen of LT4 75 mcg IV on day 3 and switched to 100 mcg oral when patient tolerated pills.Patient was down to 2 pressors on day 3 and gradually off pressors by day 6. Repeat TFT -showed improvement TSH 12 uIU/ml and FT4 0.7 ng/dl—day 5. Eventually her mentation improved and was discharged on oral LT4. Conclusion: TCM is rare complication of treatment of myxedema coma. Our patient developed shock requiring 1 pressor which unexpectedly worsened to 3 pressors requirement after initial LT4 treatment. High doses of LT4 and LT3 which is part of myxedema coma treatment sensitizes myocardial tissue to catecholamines by increasing expression of beta adrenoreceptors in cardiac myocytes with subsequent ionotropic and chronotropic effects. This may contribute to cardiac stunning and TCM. It’s beneficial to evaluate patients with myxedema coma who develop worsening cardiac status after initiation of high dose of thyroid hormone replacement for TCM. Presentation: 6/2/2024

Pharmacist initiated interventions using RxChange message communication with prescribers for electronic prescriptions: A retrospective descriptive study

BackgroundRxChange messages improve patient medication management by enhancing pharmacist-prescriber communication, but their usage patterns in the United States are not well-documented. ObjectiveTo determine intervention characteristics by pharmacists and prescribers using RxChange messages. MethodsA retrospective analysis of electronic prescription and RxChange messages from 2022 to 2023, using data from Surescripts, LLC, was conducted. This included NewRx messages and RxChange Responses, categorized by 7 RxChange use cases and Anatomical Therapeutic Chemical level 4 medication classes. Descriptive statistics and nonparametric tests were used for statistical analysis. ResultsThe study analyzed 1,361,528 RxChange messages. Therapeutic interchange was the predominant use case (76.14%). Direct approvals accounted for 10.44% of requests, approvals with changes for 42.55%, and denials for 47.01%. Script clarification had the highest approval rate (64.21%), while prior authorization faced the most frequent denials (73.38%). The top denial reason was "Request addressed through alternate methods such as phone or fax (41.50%).” The most frequent drug classes observed in the data were selective beta-2 adrenoreceptor agonists, extended-spectrum penicillins, selective serotonin reuptake inhibitors, and glucagon-like peptide 1 analogues. Time from new e-prescription issuance to RxChange request submission was longer than from request to response, with a significant statistical difference (median 1.57 vs 0.27 days, P-value < 0.05). ConclusionThis study highlights interventions pharmacists make using RxChange with electronic prescriptions to improve patient care and medication safety. It underlined the need for improved RxChange message content and data on the effectiveness of RxChange messages in improving medication use.

Revealing functional-molecular parasympathetic dysfunction in PVC-induced cardiomyopathy via dual stressor PVC and exercise

Abstract Background Exercise intolerance is a common presentation of premature ventricular contractions-induced cardiomyopathy (PVC-CM). In a canine PVC-CM model, previous studies have shown cardiac autonomic nervous system remodeling, resulting in persistent sympathetic excess. Nevertheless, the molecular mechanisms and functional implications of this neural remodeling, as well as parasympathetic alterations, remain unclear. Purpose We aim to evaluate the functional-molecular mechanisms of parasympathetic remodeling and its potential contribution to exercise intolerance in an animal model of PVC-CM. Methods We studied 15 canines (8 experimental vs 7 sham controls) chronically instrumented with pacemakers and telemetry devices to deliver 12-weeks of bigeminal PVCs (200ms coupling) to induce PVC-CM and to record sympathetic (SNA), vagal nerve activity (VNA) and heart rate (HR) over this period. Exercise challenge was conducted in sinus rhythm (SR) and in the presence of bigeminal PVCs ("dual stressor") at baseline and after development of PVC-CM. Sympatho-vagal neural and HR responses were assessed during and after exercise at baseline and after PVC-CM development, with and without PVCs, thus comparing baseline SR, baseline with PVCs, CM SR and CM with PVCs. Western Blot was performed on intrinsic and extrinsic cardiac neural tissues to evaluate molecular mechanisms of neural remodeling. Results Compared to baseline, SNA was significantly higher in PVC-CM in all phases of exercise (rest, exercise, recovery, p=0.03). In contrast, VNA was significantly lower in PVC-CM than baseline during exercise recovery (P=0.014). After exercise, HR recovery (HRR) was impaired (p=0.001), VNA lower (p=0.014) and SNA (p=0.03) higher in PVC-CM compared with baseline. Tyrosine hydroxylase (TH) immunoreactivity in the left ventricle (LV, p=0.001) and stellate ganglia (SG, p=0.03) and trans-cardiac plasma NE levels (p=0.03) were higher in PVC-CM compared with sham. Choline Acetyltransferase (CHAT) was not significantly different in either vagus (p=0.33) or LV (p=0.8) between PVC-CM vs sham. Cardiac (LV) Nerve Growth Factor (NGF), Growth Associated Protein (GAP-43) and beta 1-adrenoreceptor levels were lower (p=0.042, p=0.003, p=0.002 respectively) whereas beta 2-adreno- and muscarinic M2-cholinergic receptors were higher (p=0.02, p&amp;lt;0.01 respectively) in PVC-CM compared with sham. Conclusion Neural remodeling in PVC-CM results in an imbalanced sympathetic excess and sympathetic-parasympathetic dysfunction characterized by a loss of sympathetic functional reserve during exercise and impaired parasympathetic activity and HRR after exercise. Adaptive downregulation of NGF might explain this imbalance and dysfunction. These data open the intriguing possibility of neural-targeted therapies to reverse remodeling and restore autonomic function disrupted by chronic PVCs.GraphsMolecular

Therapeutic Potential for Beta-3 Adrenoreceptor Agonists in Peripheral Arterial Disease and Diabetic Foot Ulcers.

Annually, peripheral arterial disease is estimated to cost over USD 21 billion and diabetic foot disease an estimated at USD 9-13 billion. Mirabegron is a TGA-approved beta-3 adrenoreceptor agonist, shown to be safe and effective in the treatment of overactive bladder syndrome by stimulating bladder smooth muscle relaxation. In this review, we discuss the potential use of beta-3 adrenoreceptor agonists as therapeutic agents repurposed for peripheral arterial disease and diabetic foot ulcers. The development of both conditions is underpinned by the upregulation of oxidative stress pathways and consequential inflammation and hypoxia. In oxidative stress, there is an imbalance of reactive oxygen species and nitric oxide. Endothelial nitric oxide synthase becomes uncoupled in disease states, producing superoxide and worsening oxidative stress. Agonist stimulation of the beta-3 adrenoreceptor recouples and activates endothelial nitric oxide synthase, increasing the production of nitric oxide. This reduces circulating reactive oxygen species, thus decreasing redox modification and dysregulation of cellular proteins, causing downstream smooth muscle relaxation, improved endothelial function and increased angiogenesis. These mechanisms lead to endothelial repair in peripheral arterial disease and an enhanced perfusion in hypoxic tissue, which will likely improve the healing of chronic ulcers.

Percutaneous Tibial Nerve Stimulation in the Treatment of Refractory Idiopathic Overactive Bladder Syndrome: A Retrospective Cohort Study.

Overactive bladder (OAB) is a syndrome defined as urinary urgency, accompanied by increased frequency and nocturia with or without urge incontinence, in the absence of urinary tract infection or other obvious pathology. The standard therapies are anticholinergic agents, selective beta-3 adrenoreceptor agonists, or intradetrusor injections of botulinum toxin (BTX-A). For patients with contraindications for BTX-A or drug therapies, percutaneous tibial nerve stimulation (PTNS) may be used. PTNS shows fewer side effects than anticholinergic drugs and costs less than BTX-A. The primary outcome of this study was to assess the efficacy of PTNS in women with refractory OAB. Women with refractory OAB undergoing PTNS at our tertiary referral center from 2017 to 2019 were included. The validated German Female Pelvic Floor Questionnaire and a micturition protocol were filled out before and after PTNS. PTNS was applied weekly for 12 weeks. Improvements in OAB symptoms were seen in daily micturition frequency, urgency, and urgency incontinence from pre- to post-PTNS (p < 0.006). Impairments to quality of daily life were significantly (p < 0.0002) less severe after PTNS. There was a significant reduction in daytime voiding frequency from a median of nine to five (p < 0.0001). Substantial reductions in OAB symptoms, daily micturition frequency, urgency, and urgency incontinence were found in patients with refractory OAB after PTNS.

Anxiolytic-like effects of Atenolol injected into the nucleus accumbens septi in rats after restrain stress in the elevated plus maze test

Objetives: Previously, we observed that the injection of glutamate antagonists injected within the Nucleus Accumbens Septi (NAS) produced an anxiolytic-like effect in the elevated plus maze (EPM) test in basal non-disturbed state rats. The effect of metoprolol, a specific Beta-1 Adrenoreceptor antagonist in the EPM, was studied previously in a resting condition in male rats bilaterally cannulated in the NAS. Methods: Rats were previously submitted to restrain stress and divided into four groups. They received bilaterally 1 μl injections of saline (n=13) or atenolol in different doses within the NAS: 0.75 (n=15), 1 (n=13) and 2 µg/1 µl (n=13), 15 min before testing. Rats were maintained under restrain between injection and test. Results: Time Spent in the Open Arm (TSOA) was modified by treatment (F = 4.239, p = 0.0096, df = 3) and increased by the medium dose group when it was compared with the saline group (p&lt;0.05) and the lowest dose group (p&lt;0.01). Open arms entries (OAE) were modified by treatment (F = 3.461, p = 0.0231, df = 3). This parameter was increased by the medium dose of atenolol (p&lt;0.05) when compared to saline and the lowest dose. No significant differences were observed in other parameters studied. Conclusion: We conclude that atenolol beta-1 receptor blockade within the NAS after restraint leads to an anxiolytic-like effect related to an increase in the Time Spent in the Open Arm (TSOA), and behavioural disinhibition, evidenced in the increase in the Open Arm Entries (OAE), showing a specific behavioural pattern.

Polymorphic variants of the beta 2-adrenoreceptor gene (adrb2) in healthy Caucasians of the Gomel region

Objective. To study the frequency of polymorphic loci rs1042713 and rs1042714 of the β2-adrenoreceptor gene in healthy Caucasians of the Gomel region.Materials and methods. A one-step study of 143 healthy volunteers living in Gomel region was conducted. This group included 86 (60,14%) men and 57 (39,86%) women. The average age was 36.0±10.20 years. Two single nucleotide polymorphisms (SNPs) rs1042713 and rs1042714 were genotyped in blood samples of patients by polymerase chain reaction (PCR).Results. Among the genotypes of the rs1042713 polymorphic locus, the most common was the AG genotype (45.4%). The GG (44.1%) and AA (10.5%) genotypes were less common. The rs1042714 polymorphic locus was characterized by a more frequent presence of the CG genotype (48.9%). The CC (25.9%) and GG (25.2%) genotypes were detected less frequently. Among the alleles of polymorphic locus rs1042713, allele G was the most common (66.8%). Of the alleles of the polymorphic locus rs1042714, the C allele was more frequent (50.4%). The ADRB2 gene was more frequently represented by the AG/CG and GG/CG haplotypes (32.9% and 39.9%, respectively). AA/GG, AG/GG, and GG/ GG haplotypes were not detected among the volunteers examined.Conclusion. AG and CG genotypes, haplotypes AG/CG and GG/CG for the polymorphic locus rs1042713 and rs1042714, respectively, were more common among Caucasians living in the Gomel region. The G allele for the polymorphic locus rs1042713 and the C allele for rs1042714 turned out to be the most common among the alleles.

Formulate and Evaluate, Fast Dissolving thin Film of Metoprolol Succinate

Objective: Metoprolol succinate, which is used to treat cardiovascular disorders, is a strong beta-1 adrenoreceptor blocker with cardio-selective effect but is heavily metabolised in the liver during the first pass. Our goal is to minimise hypertension by creating a film of metoprolol succinate that dissolves quickly.&#x0D; Methods: Metoprolol succinate films that dissolve in the mouth were made utilising a solvent casting technique. HPMC E5 was used as the film-forming agent, PEG400 was used as the plasticizer, and honey was included as the film-modifying agent in the final formulation. HPMC E15 (X1) and honey (X2) concentrations were used as independent variables, whereas disintegration time (DT), tensile strength (TS), and % cumulative drug release (CDR) were used as dependent variables in a 32-full factorial design. Thickness, folding endurance, tensile strength, disintegration time, and drug release were among the criteria used to assess the manufactured films. Results showed that HPMC E15 and honey both positively impacted DT and TS while negatively impacting CDR.&#x0D; Results: The optimum formulation was determined to be the one with a DT of 58.0 ±1.01 seconds, an in vitro drug release of 105.32± 1.55, and a tensile strength of 73.55 ± 1.37 g/cm2.&#x0D; Conclusion: Thus, employing a solvent casting method, a fast-dissolving thin film of Metoprolol succinate was created with effective taste masking and prompt in vitro drug release.&#x0D; Keywords: Metoprolol succinate, Fast dissolving oral film, HPMC E5, Honey, Solvent casting

1681-P: RNA Binding Protein HuR Is Essential for Adaptive Thermogenesis

Brown adipose tissue (BAT) plays a key role in the regulated production of heat in response to cold temperatures, known as adaptive thermogenesis. While the transcriptional mechanisms underlying the thermogenic function of BAT has been widely studied, the role of posttranscriptional processes in BAT thermogenesis remain largely unexplored. RNA binding proteins are central to the control multiple aspects of posttranscriptional RNA biology. Here, we identify brown fat HuR as a critical regulator of adaptive thermogenesis. Mice with adipocyte-specific HuR deletion (AKO) were unable to increase energy expenditure in response to a cold challenge, resulting in marked hypothermia. HuR AKO mice housed at thermoneutrality also failed to increase energy expenditure upon beta-3 adrenoreceptor agonist treatment, indicating a defect in thermogenic BAT. HuR-deleted brown adipocytes displayed impaired mitochondrial respiration under β-adrenergic stimulation. RNA sequencing data revealed that loss of HuR led to downregulation of genes associated with TCA cycle, β-oxidation, and mTORC1 signaling in BAT. Our findings reveal an essential role for RNA binding protein HuR in thermogenic programs of the brown adipocyte and highlight the importance of posttranscriptional processes in BAT thermogenesis. Disclosure K.Park: None. S.Choi: None. J.Suh: None.

Clinical Outcomes Depending on Sympathetic Innervation in Pancreatic Cancer.

The aim of our study was to evaluate sympathetic neuronal remodeling in patients with pancreatic cancer, together with its correlation with clinical outcomes. In this descriptive, retrospective study, we analyzed pancreatic cancer specimens and peritumoral pancreatic tissue from 122 patients. We also investigated tyrosine hydroxylase immunoreactivity for the analysis of sympathetic nerve fibers and beta 2 adrenoreceptors immunoreactivity. To investigate the potential interaction between tyrosine hydroxylase (TH), beta 2 adrenoreceptors (B2A) immunoreactivity, and clinicopathological outcomes, we used the median to classify each case as TH+, respectively, B2A+ (if it presented a value higher than the median). Firstly, the overall survival was analyzed according to TH and B2A immunoreactivity, in both intratumoral and peritumoral tissue. Only B2A immunoreactivity in the peritumoral pancreatic tissue influenced overall survival at 5 years of follow-up; thus, B2A+ patients recorded a 5-year survival of only 3% compared to B2A- patients who recorded an overall survival at 5 years of follow-up of 14% (HR = 1.758, 95% CI of ratio 1.297 to 2.938, p = 0.0004). Additionally, the increased immunoreactivity of B2A in the peritumoral tissue was also associated with other factors of poor prognosis, such as moderately or poorly differentiated tumors, the absence of response to first-line chemotherapy, or metastatic disease. The increased immunoreactivity of beta 2 adrenoreceptors in pancreatic peritumoral tissue represents a poor prognostic factor in pancreatic cancer.

Effect of Pharmacotherapy for Overactive Bladder on the Incidence of and Factors Related to Urinary Tract Infection: A Systematic Review and Meta-analysis.

The aim of this meta-analysis was to investigate the effect of pharmacotherapy for overactive bladder on the pathogenesis of urinary tract infection. A comprehensive search was performed in MEDLINE and the Cochrane Library using terms for overactive bladder, antimuscarinic agents, and beta 3-adrenoceptor agonists. The primary end point was the emergence of urinary tract infection after pharmacotherapy for overactive bladder. The secondary end point was the emergence of urinary retention, dysuria, and/or increased residual urine volume after overactive bladder treatment. Meta-analyses were conducted using random-effects models. A total of 35,939 patients in 33 trials (29 trials of antimuscarinic agents vs placebo, and 9 trials of beta 3-adrenoceptor agonists vs placebo) that included patients with overactive bladder were identified. At 1-3 months after treatment, the incidence of urinary tract infections was statistically significantly higher in the patients treated with antimuscarinic agents (RR: 1.23, 95% CI: 1.04, 1.45; P = .013) than in the placebo control group. The incidence of urinary tract infections was not increased in the patients treated with beta 3-adrenoceptor agonists (RR: 1.04, 95% CI: 0.76, 1.42; P = .796). Antimuscarinic agents also statistically significantly increased the risks of urinary retention, dysuria, and/or increased residual urine volume (RR: 2.88, 95% CI: 1.79, 4.63; P < .001), whereas beta 3-adrenoceptor agonists did not (RR: 1.26, 95% CI: 0.38, 4.14; P = .708). This meta-analysis showed that antimuscarinic agents statistically significantly increased the incidences of urinary tract infection and lower urinary tract symptoms and dysfunction, but beta 3-adrenoceptor agonists did not. To prevent urinary tract infection emergence, beta 3-adrenoceptor agonists might be safer than antimuscarinic agents.

Inhibition of signaling downstream of beta-2 adrenoceptor by propranolol in prostate cancer cells.

There is accumulating evidence that propranolol, an antagonist of beta-1 and beta-2 adrenoreceptors, extends survival of patients with prostate cancer; yet it is not known whether propranolol inhibits beta-adrenergic signaling in prostate cancer cells, or systemic effects of propranolol play the leading role in slowing down cancer progression. Recently initiated clinical studies offer a possibility to test whether administration of propranolol inhibits signaling pathways in prostate tumors, however, there is limited information on the dynamics of signaling pathways activated downstream of beta-2 adrenoreceptors in prostate cancer cells and on the inactivation of these pathways upon propranolol administration. Western blot analysis was used to test the effects of epinephrine and propranolol on activation of protein kinase(PKA) signaling in mouse prostates and PKA, extracellular signal-regulated kinase (ERK), and protein kinase B/AKT (AKT) signaling in prostate cancer cell lines. In prostate cancer cell lines epinephrine induced robust phosphorylation of PKA substrates pS133CREB and pS157VASP that was evident 2 min after treatments and lasted for 3-6 h. Epinephrine induced phosphorylation of AKT in PTEN-positive 22Rv1 cells, whereas changes of constitutive AKT phosphorylation were minimal in PTEN-negative PC3, C42, and LNCaP cells. A modest short-term increase of pERK in response to epinephrine was observed in all tested cell lines. Incubation of prostate cancer cells with 10-fold molar excess of propranolol for 30 min inhibited all downstream pathways activated by epinephrine. Subjecting mice to immobilization stress induced phosphorylation of S133CREB, whereas injection of propranolol at 1.5 mg/kg prevented the stress-induced phosphorylation. The analysis of pS133CREB and pS157VASP allows measuring activation of PKA signaling downstream of beta-2 adrenoreceptors. Presented results on the ratio of propranolol/epinephrine and the time needed to inhibit signaling downstream of beta-2 adrenoreceptors will help to design clinical studies that examine the effects of propranolol on prostate tumors.

PSUN369 Glucagonoma-Associated Dilated Cardiomyopathy in a Young Female: A Case Report

Abstract Background Dilated cardiomyopathy has been reported in patients with glucagonoma. Since glucagon increases myocardial cAMP levels independent of beta adrenoreceptor blockade, thereby increasing heart rate and cardiac output, chronic excessive glucagon stimulation of the heart may lead to cardiomyopathy (Chang-Chretien, 2004). Clinical Case A 26 year old female presented with a 2-year history of palpable epigastric mass, vomiting and weight loss. Abdominal CT showed a heterogeneously enhancing, lobulated pancreatic head-body mass measuring 6.7×6.1×9.9 cm and a hypo-enhancing nodule in hepatic segment IVb, worrisome for metastasis. Endoscopy-guided FNAB of the pancreatic mass revealed a well-differentiated pNET, Grade 3. Chromogranin and synaptophysin stains were positive, Ki-67 index was 33.6%. She was lost to follow-up. After 4 months, she was admitted due to 1 week history of increased vomiting episodes up to 10x daily and abdominal discomfort with 2 day history of incomprehensible speech and right-sided weakness. On examination, she was weak-looking, tachycardic (114 bpm), underweight (BMI 17.45 kg/m2) and with palpable, hard, non-tender epigastric mass measuring 10×7 cm. She also had hyperpigmented patches on both legs initially manifesting as intermittent oozing excoriations over the past 2 years. Cranial MRI revealed subacute CVD infarct. Anticoagulation was given. On the second day, she started having diarrheal episodes. Supportive management was given. Serum glucagon was markedly elevated (&amp;gt;25,000 pg/mL, normal &amp;lt;80). Serum PP (6562 pg/mL, normal &amp;lt;228) and gastrin (621 pg/mL, normal 13-115) were elevated. Serum VIP (&amp;lt;50 pg/mL, normal &amp;lt;75) was normal. Further investigations showed prediabetes (FBS 112 mg/dL, HbA1c 5.7%) and normocytic, normochromic anemia. Screening for MEN1 was unremarkable. On the third day, she had progression of slurred speech and right-sided weakness. Cranial MRI revealed acute lacunar infarcts. As part of hypercoagulability workup, 2D-Echocardiogram showed depressed ejection fraction (20.9%), dilated LV with normal relative wall thickness, and global hypokinesia of the LV wall, confirming dilated cardiomyopathy. Carotid and Venous Duplex scans were normal. Anti-heart failure regimen was initiated. Due to her current neurologic, cardiac and metabolic conditions, she cannot proceed with surgery and chemotherapy. She was given octreotide injection 30 mg every 4 weeks for 3 doses. Post-treatment, repeat abdominal CT and 2D-Echocardiogram showed no significant change. In the meantime, she had improved appetite and no recurrence of vomiting nor diarrhea. She denies palpitations and can better tolerate walking and climbing stairs. Conclusion We reported a rare case of glucagonoma in a young female with documented constellation of symptoms and complications associated with the syndrome, prominently including dilated cardiomyopathy. It is therefore recommended that cardiovascular evaluation should be initiated at the time of glucagonoma diagnosis for timely and appropriate management. Presentation: Sunday, June 12, 2022 12:30 p.m. - 2:30 p.m.

Psychostimulants Modafinil, Atomoxetine and Guanfacine Impair Bone Cell Differentiation and MSC Migration.

Attention deficit hyperactivity disorder (ADHD) is one of the most common worldwide mental disorders in children, young and adults. If left untreated, the disorder can continue into adulthood. The abuse of ADHD-related drugs to improve mental performance for studying, working and everyday life is also rising. The potentially high number of subjects with controlled or uncontrolled use of such substances increases the impact of possible side effects. It has been shown before that the early ADHD drug methylphenidate influences bone metabolism negatively. This study focused on the influence of three more recent cognitive enhancers, modafinil, atomoxetine and guanfacine, on the differentiation of mesenchymal stem cells to osteoblasts and on their cell functions, including migration. Human mesenchymal stem cells (hMSCs) were incubated with a therapeutic plasma dosage of modafinil, atomoxetine and guanfacine. Gene expression analyses revealed a high beta-2 adrenoreceptor expression in hMSC, suggesting it as a possible pathway to stimulate action. In bone formation assays, all three cognitive enhancers caused a significant decrease in the mineralized matrix and an early slight reduction of cell viability without triggering apoptosis or necrosis. While there was no effect of the three substances on early differentiation, they showed differing effects on the expression of osterix (OSX), receptor activator of NF-κB ligand (RANKL) and osteoprotegerin (OPG) in the later stages of osteoblast development, suggesting alternative modes of action. All three substances significantly inhibited hMSC migration. This effect could be rescued by a selective beta-blocker (Imperial Chemical Industries ICI-118,551) in modafinil and atomoxetine, suggesting mediation via beta-2 receptor stimulation. In conclusion, modafinil, atomoxetine and guanfacine negatively influence hMSC differentiation to bone-forming osteoblasts and cell migration through different intracellular pathways.

1381-P: GDF15 Deficiency in Brown Adipose Tissue Does Not Affect Thermogenesis, but Exacerbates Diet-Induced Obesity

Growth and differentiation factor 15 (GDF15) is induced in brown adipocytes in response to thermogenic stimuli, as well as high-fat feeding in mice. However, whether brown adipose tissue (BAT) -derived GDF15 is required to regulate BAT thermogenesis or energy homeostasis is unclear. In the present study, we sought to test the hypothesis that BAT-derived GDF15 is necessary to mediate thermogenesis and systemic adaptations to diet-induced obesity (DIO) . We generated mice lacking GDF15 specifically in BAT by crossing Gdf15 floxed mice with mice harboring the Cre recombinase under the control of the Ucp1 promoter (GDF15 BAT KO) . GDF15 BAT KO mice were treated with the beta adrenoreceptor agonist CL316,243 (CL) for 5 days to induce thermogenesis, or fed a high-fat diet (60% fat content) for 12 weeks to induce DIO. CL treatment promoted a significant induction in Gdf15 mRNA levels in the BAT of WT mice, which, as expected, was prevented in KO mice. Nonetheless, serum GDF15 levels were similarly induced by CL in both WT and KO mice. CL-induced activation of thermogenic genes in BAT, such as Ucp1 and Dio2, was comparable between genotypes, and core body temperature was unchanged between WT and KO mice. After 12 weeks of high-fat feeding, KO mice had significantly increased body weight and fat mass relative to WT mice. However, food intake, locomotor activity and energy expenditure were unchanged between groups. Respiratory exchange ratio was significantly higher in KO mice, indicating a relative preference for carbohydrate as fuel. Although glucose tolerance was unchanged between genotypes, insulin sensitivity was impaired in KO mice. Taken together, our data indicates that BAT-derived GDF15 does not contribute to GDF15 circulating levels in response to CL treatment and is largely dispensable for CL-induced BAT thermogenesis. However, BAT-derived GDF15 seems to be required to regulate diet-induced weight gain and insulin sensitivity. Disclosure J.Jena: None. K.Kato: None. A.A.Marti: None. R.Pereira: None. Funding NIHDK125405

Salbutamol for analgesia in renal colic: study protocol for a prospective, randomised, placebo-controlled phase II trial (SARC)

BackgroundRenal colic is the pain experienced by a patient when a renal calculus (kidney stone) causes partial or complete obstruction of part of the renal outflow tract. The standard analgesic regimes for renal colic are often ineffective; in some studies, less than half of patients achieve complete pain relief, and a large proportion of patients require rescue analgesia within 4 h. Current analgesic regimes are also associated with significant side effects including nausea, vomiting, drowsiness and respiratory depression. It has been hypothesised that beta adrenoreceptor agonists, such as salbutamol, may reduce the pain of renal colic. They have been shown to impact a number of factors that target the physiological causes of pain in renal colic (ureteric spasm and increased peristalsis, increased pressure at the renal pelvis and prostaglandin release with inflammation). There is biological plausibility and a body of evidence sufficient to suggest that this novel treatment for the pain of renal colic should be taken to a phase II clinical trial. The aim of this trial is to test whether salbutamol is an efficacious analgesic adjunct when added to the standard analgesic regime for patients presenting to the ED with subsequently confirmed renal colic.MethodsA phase II, randomised, placebo-controlled trial will be performed in an acute NHS Trust in the East Midlands. Patients presenting to the emergency department with pain requiring IV analgesia and working diagnosis of renal colic will be randomised to receive standard analgesia ± a single intravenous injection of Salbutamol. Secondary study objectives will explore the feasibility of conducting a larger, phase III trial.DiscussionThe trial will provide important information about the efficacy of salbutamol as an analgesic adjunct in renal colic. It will also guide the development of a definitive phase III trial to test the cost and clinical effectiveness of salbutamol as an analgesic adjunct in renal colic. Salbutamol benefits from widespread use across the health service for multiple indications, extensive staff familiarity and a good side effect profile; therefore, its potential use for pain relief may have significant benefits for patient care.Trial registrationISRCTN Registry ISRCTN14552440. Registered on 22 July 2019

The Effect of Beta Adrenoreceptor Blockers on Viability and Cell Colony Formation of Non-Small Cell Lung Cancer Cell Lines A549 and H1299

Beta adrenoblockers are a large class of drugs used to treat cardiovascular diseases, migraines, glaucoma and hyperthyroidism. Over the last couple of decades, the anticancer effects of these compounds have been extensively studied. However, the exact mechanism is still not known, and more detailed studies are required. The aim of our study was to evaluate the anticancer activity of beta adrenoblockers in non-small cell lung cancer cell lines A549 and H1299. In order to find the relationship with their selectivity to beta adrenoreceptors, selective (atenolol, betaxolol, esmolol, metoprolol) and non-selective (pindolol, propranolol and timolol) beta blockers were tested. The effect on cell viability was evaluated by MTT assay, and the activity on cell ability to form colonies was tested by clonogenic assay. The type of cell death was evaluated by cell double staining with Hoechst 33342 and Propidium iodide. The most active adrenoblockers against both tested cancer cell lines were propranolol and betaxolol. They completely inhibited lung cancer cell colony formation at 90% of the EC50 (half-maximal effective concentration) value. Most tested compounds induced cell death through apoptosis and necrosis. There was no correlation established between beta adrenoblocker anticancer activity and their selectivity to beta adrenoreceptors.

The ELSA trial: single versus combinatory effects of non-prohibited beta-2 agonists on skeletal muscle metabolism, cardio-pulmonary function and endurance performance\u2014study protocol for a randomized 4-way balanced cross-over trial

BackgroundAsthma and/or airway hyper-responsiveness (AHR) are common in elite endurance athletes with a high prevalence rate of beta-2 adrenoreceptor (beta-2) agonists use. Nevertheless, there are data on dose-dependent ergogenic effects of beta-2 agonists suggesting increased muscle strength, endurance and neuromuscular performance. Therefore, most beta-2 agonists belong to the World Anti Doping Agency (WADA) list of prohibited substances and it is tempting to speculate that illegitimate use of beta-2 agonists might be a common practice to boost performance in competitive sports. It is currently unknown whether or not inhaled beta-2 agonists enhance performance by stimulatory effects in skeletal and cardiac muscle.MethodsThe ELSA trial is a double-blinded, placebo-controlled, randomized, balanced, four-way cross-over study. Study participants (n=24, 12 ♀, 12 ♂) complete four study arms (i.e. periods with treatment A, placebo; B, salbutamol; C, formoterol; D, formoterol + salbutamol) in random order after an initial preliminary testing session. Participants inhale the study medication 20 min before the 10-min time trial (TT; exercise performance test), where participants cycle 10 min at the highest possible workload. Cardiac output is measured continuously. A skeletal muscle biopsy is collected 3 h after the TT. Study endpoints include measures of skeletal muscle expression of nuclear receptors, hormones and cytokine levels, urinary and plasma concentrations of salbutamol and formoterol, circulating cardiac markers, cardiopulmonary function and exercise performance (average power and peak power during the TT). Blood and urine are collected and respiratory testing is performed 24 h post TT.Summary/conclusionsThis clinical trial evaluates the potential performance-enhancing effects of non-prohibited, not medically indicated inhaled short- and long-acting beta-2 agonists on skeletal muscle gene expression, endocrine regulation, cardiac biomarkers, cardiopulmonary function and acute endurance exercise performance. These data will be used by WADA to adapt the annually published list of prohibited substances (WADA 2021) and will be published in scientific journals.Trial registrationThe trial is registered at the European Clinical Trials Database (Eudra CT) with the number: 2015-005598-19 as well as at the German register for clinical studies (DRKS number 00010574).

Efficacy and safety of intravenous beta-blockers in acute atrial fibrillation and flutter is dependent on beta-1 selectivity: a systematic review and meta-analysis of randomised trials

Abstract Background Intravenous (IV) beta-blockers are commonly used to manage patients with acute atrial fibrillation (AF) and atrial flutter (AFl). Important pharmacodynamic differences exist amongst beta-blockers, and the choice of beta-blocker or other therapy is often not evidence-based. Purpose Systematic review and meta-analysis of randomised controlled trials (RCTs) in the setting of acute AF/AFl to assess the efficacy and safety of IV beta-blockers against other pharmacological interventions (diltiazem, verapamil, digoxin, anti-arrhythmic drugs or placebo). Methods Prospectively registered (PROSPERO: CRD42020204772). MEDLINE, EMBASE and Cochrane Register were searched from inception to August 2020. The primary outcomes were reduction in heart rate and proportion of patients achieving study-defined target heart rate. Secondary outcomes included conversion to sinus rhythm and incidence of adverse events. Beta-blockers were divided according to beta-1 adrenoreceptor selectivity. Meta-analysis was performed to calculate risk ratios (RR) and standardised mean differences (SMD) using random-effects, and fixed-effects within beta-1 subgroups. Results From 5974 studies, 12 RCTs were included with variable risk of bias, encompassing 1152 participants with mean age 62 years, 38% women and baseline heart rate 137 beats/minute. With high heterogeneity (I2=87%; p&amp;lt;0.001), there was no difference in the reduction in heart rate between beta-blockers and comparators (SMD −0.65, 95% CI −1.63–0.21; p=0.19), and no difference in the proportion that achieved target heart rate (RR 0.85, 95% CI 0.36–1.97; p=0.70). Analysis by beta-1 selectivity demonstrated that conventional beta-1 blockers (metoprolol, esmolol) were inferior for target heart rate reduction (RR 0.33, 95% CI 0.17–0.64; p=0.001), whereas super-selective agents (landiolol) were superior (RR 1.98, 95% CI 1.54–2.54; p&amp;lt;0.001). There was no difference in the rate of conversion to sinus rhythm between beta-blockers and comparators (RR 1.15, 95% CI 0.92–1.44; p=0.21). Adverse events were similar in both groups overall, with no significant difference in hypotension (RR 1.74, 95% CI 0.85–3.58; p=0.13), bradycardia (RR 0.86, 95% CI 0.19–3.81; p=0.153) or events leading to drug discontinuation (RR 1.16, 95% CI 0.26–5.15; p=0.84). Assessment by beta-1 selectivity showed that hypotension and bradycardia were more frequent with non-selective beta-blockers (sotalol) than comparators (RR 4.57, 95% CI 1.92–10.85; p=0.001 and 5.97, 95% CI 1.34–26.57; p=0.019). Conclusion There is no difference between IV beta-blockers overall and other medications for the control of acute AF/AFl, although better efficacy was shown for beta-blockers with higher beta-1 selectivity. IV beta-blockers were as safe as comparator agents, with the exception of non-selective beta-blockers. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): Independent systematic review commissioned by Amomed Pharma. Target heart rate and hypotension events

Class-specific responses of brown adipose tissue to steroidal and nonsteroidal mineralocorticoid receptor antagonists.

Aldosterone exerts deleterious effects on the cardiovascular system and promotes adipose tissue expansion via mineralocorticoid receptor (MR) activation. We previously demonstrated that administration of steroidal mineralocorticoid receptor antagonists (MRA) in mice fed a moderate high-fat diet is able to reduce white adipose tissue (WAT) expansion, stimulate browning of WAT and activate interscapular brown adipose tissue (iBAT). Here, we aimed to compare the metabolic and adipose tissue-specific effects of the novel non-steroidal MRA finerenone (Fine) and spironolactone (Spiro) in a mouse model of very high-fat diet (HFD)-induced obesity. C57BL/6 J male mice were fed a 60% HFD containing or not Spiro or Fine for 12 weeks. WAT and iBAT morphology and adipose tissue gene expression analysis were assessed. After 12 weeks, both groups of mice showed similar weight gain compared to the HFD group. Histological and molecular analyses of WAT did not show significant differences among all experimental groups; differently, iBAT histological analysis revealed that Fine was able to increase recruitment of brown adipocytes in this depot, whereas mice treated with Spiro failed to elicit any iBAT response, as indicated by no changes in lipid droplets size and iBAT density, compared to HFD. Increased iBAT recruitment could explain, at least in part, the improved insulin resistance observed in mice treated with Fine, as shown by a significant reduction in homeostasis model assessment of insulin resistance (HOMA) index. These findings were confirmed by gene expression analysis of ucp-1, pgc1-α, and beta-3 adrenoreceptor (Adrb3) in iBAT, revealing significantly higher expression of these thermogenic genes in HFD + Fine group compared to HFD, whereas Spiro did not modify their expression. In summary, we demonstrated that, differently from Fine, Spiro did not induce iBAT recruitment. Our current study suggests that Fine, through its direct effects on iBAT, represents a promising pharmacologic tool to treat human metabolic diseases associated with adipose tissue dysfunctions.