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Talanta Jan 2019A strategy to study thermodynamic binding constants by affinity capillary electrophoresis (ACE) is presented. In order to simplify mathematical treatment, analogy with...
A strategy to study thermodynamic binding constants by affinity capillary electrophoresis (ACE) is presented. In order to simplify mathematical treatment, analogy with acid-base dissociation equilibrium is proposed: instead of ligand concentration [X], negative logarithm of ligand concentration (or activity), pX = -log[X], is used. On this base, and taking into account ionic activities, a general procedure for obtaining thermodynamic binding constants is proposed. In addition, the method provides electrophoretic mobilities of the free analyte and analyte-ligand complex, even when binding constants are low and thus, the complexed analyte fraction is also low. This is useful as a base to rationally analyze a diversity of situations, i.e., different mathematical dependencies are obtained when analytes and ligands with different charges are combined. Practical considerations are given for carrying out a full experimental design. Enantiomeric ACE separation based on the use of chiral selectors is addressed. 2-hydroxypropyl-β-cyclodextrin was chosen as a model ligand, and both enantiomeric forms of four pharmaceutical drugs (propranolol, pindolol, oxprenolol and homatropine methylbromide) were considered as model analytes. Practical aspects are detailed and thermodynamic binding constants as well as free and complexed analytes mobilities are determined.
PubMed: 30348416
DOI: 10.1016/j.talanta.2018.09.044 -
European Child & Adolescent Psychiatry Oct 2018The aim of this study is to gather evidence of head-to-head double-blind randomized-controlled trials on the efficacy and safety of available treatments for attention... (Meta-Analysis)
Meta-Analysis Review
The aim of this study is to gather evidence of head-to-head double-blind randomized-controlled trials on the efficacy and safety of available treatments for attention deficit hyperactivity disorder (ADHD) in children and adolescents. A systematic review was conducted by two independent reviewers in ten electronic databases (PROSPERO register CRD42016043239). Methodological quality of included studies was evaluated according to the Jadad scale. Network meta-analyses were performed including double-blinded head-to-head trials comparing active allopathic drugs in patients (0-18 years old) diagnosed with ADHD. The results of efficacy and safety of atomoxetine (ATX), bupropion, buspirone (BSP), dexamphetamine, edivoxetine (EDX), guanfacine (GXR), lisdexamfetamine (LDX), methylphenidate (MPH), mixed amphetamine salts, modafinil, pindolol (PDL), reboxetine (RBX), selegiline, and venlafaxine were analyzed using ADDIS software v.1.16.5. Forty-eight trials were identified (n = 4169 participants), of which 12 were used for efficacy analysis and 33 for safety analysis. On the CGI-I scale, the analysis revealed that MPH was more effective than ATX and GXR. For the safety outcomes, according to drug ranks, LDX was more likely to cause sleep disorders (39%) as well as loss of appetite (65%) and behavior problems such as irritability (60%). BSP (71%) and EDX (44%) caused less appetite decrease. For behavioral effects, PDL was considered safest (50%). For any adverse events, RBX (89%) was the safest alternative. The lack of head-to-head trials properly reporting outcomes of interest limited some comparisons. Network meta-analysis offered a broader overview on the available treatments for ADHD, especially for safety issues, and contributes towards evidence gathering and clinical practice decisions. A core outcome set for ADHD should be designed to guide the conduction and report of clinical trials.
Topics: Attention Deficit Disorder with Hyperactivity; Child; Female; Humans; Male; Treatment Outcome
PubMed: 29460165
DOI: 10.1007/s00787-018-1125-0 -
Pulmonary Pharmacology & Therapeutics Apr 2020The β-adrenergic receptor (β-AR) plays an important role in regulating a variety of cell and organ functions in different animal species and is an important target in...
The β-adrenergic receptor (β-AR) plays an important role in regulating a variety of cell and organ functions in different animal species and is an important target in asthma pathogenesis and therapy. The β-AR expression and function in equine bronchial epithelial cells (EBEC) were not known but innervation and significant decrease in receptor level were reported in the equine bronchial tissues from asthmatic horses. I-iodocyanopindolol (ICYP) binding studies were undertaken in primary freshly isolated and cultured EBEC to identify the presence of the β-ARs. The receptor distribution was assessed using subtype-selective β-AR antagonists (ICI 118 551 (β) and CGP 20712A (β). The β-AR function was confirmed by measuring the agonist-induced intracellular cAMP accumulation in freshly isolated and cultured EBEC. In both freshly isolated and cultured EBEC, the specific ICYP binding was saturable and of high affinity. The maximal receptor density (B) was 9763 ± 140 binding sites/cell (mean ± SEM, n = 7) and 10575 ± 194 binding sites/cell (mean ± SEM, n = 5) in freshly isolated and cultured EBEC, respectively. The receptor affinity to the ligand (K) was also not different between the two cell conditions. ICI 118.551 displaced ICYP with 25 000-fold higher affinity than CGP 20712A. Moreover, in both fresh isolated and cultured EBEC, cAMP-accumulation was stimulated with a rank-order of potency of isoproterenol > adrenaline > noradrenaline. These results highlight the β-AR to be a key subtype in both freshly isolated and cultured primary EBEC.
Topics: Adrenergic beta-Antagonists; Animals; Bronchi; Cells, Cultured; Cyclic AMP; Epithelial Cells; Horses; Imidazoles; Iodocyanopindolol; Isoproterenol; Primary Cell Culture; Propanolamines; Receptors, Adrenergic, beta; Receptors, Adrenergic, beta-1; Receptors, Adrenergic, beta-2
PubMed: 31962137
DOI: 10.1016/j.pupt.2020.101897 -
Chirality May 2021In this study, a novel hydroxypropyl-γ-cyclodextrin (HP-γ-CD) functionalized monolithic capillary column was prepared by one-pot sequential strategy and used for...
In this study, a novel hydroxypropyl-γ-cyclodextrin (HP-γ-CD) functionalized monolithic capillary column was prepared by one-pot sequential strategy and used for chiral separation in capillary electrochromatography for the first time. In one pot, GMA-HP-γ-CD as functional monomer was allowed to be formed via the ring opening reaction between HP-γ-CD and glycidyl methacrylate (GMA) catalyzed by 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and then copolymerized directly with ethylene dimethacrylate (EDMA) and 2-acrylamido-2-methyl propane sulfonic acid (AMPS) in the presence of porogenic solvents via thermally initiated free radical polymerization. The preparation conditions of monoliths were optimized. Enantiomer separations of six chiral drugs including pindolol, clorprenaline, tulobuterol, clenbuterol, propranolol, and tropicamide were achieved on the monolith. Among them, pindolol, clorprenaline, and tropicamide were baseline separated with resolution values of 1.62, 1.73, and 1.55, respectively. The mechanism of enantiomer separation was discussed by comparison of the HP-γ-CD and HP-β-CD functionalized monoliths.
Topics: Capillary Electrochromatography; Pharmaceutical Preparations; Polymerization; Stereoisomerism; gamma-Cyclodextrins
PubMed: 33604997
DOI: 10.1002/chir.23300 -
Sheng Li Xue Bao : [Acta Physiologica... Dec 2022A large number of β-adrenergic receptor (β-AR) agonists and antagonists are widely used in the treatment of cardiovascular diseases and other diseases. Nonetheless, it...
A large number of β-adrenergic receptor (β-AR) agonists and antagonists are widely used in the treatment of cardiovascular diseases and other diseases. Nonetheless, it remains unclear whether these commonly used β-AR drugs can activate downstream β- arrestin-biased signaling pathways. The objective of this study was to investigate β-arrestin2 recruitment effects of β-AR agonists and antagonists that were commonly used in clinical practice. We used TANGO (transcriptional activation following arrestin translocation) assay to detect the β-arrestin2 recruitment by β-AR ligands in HEK293 cell line (HTLA cells) stably transfected with tetracycline transactivator protein (tTA) dependent luciferase reporter and β-arrestin2-TEV fusion gene. Upon activation of β-AR by a β-AR ligand, β-arrestin2 was recruited to the C terminus of the receptor, followed by cleavage of the G protein-coupled receptors (GPCRs) fusion protein at the TEV protease-cleavage site. The cleavage resulted in the release of tTA, which, after being transported to the nucleus, activated transcription of the luciferase reporter gene. The results showed that β-AR non-selective agonists epinephrine, noradrenaline and isoprenaline all promoted β-arrestin2 recruitment at β1-AR and β2-AR. β1-AR selective agonists dobutamine and denopamine both promoted β-arrestin2 recruitment at β1-AR. β2-AR selective agonists procaterol and salbutamol promoted β-arrestin2 recruitment at β2-AR. β-AR non-selective antagonists alprenolol and pindolol promoted β-arrestin2 recruitment at β1-AR. β1-AR selective antagonists celiprolol and bevantolol showed β-arrestin2 recruitment at β1-AR. β2-AR selective antagonists butoxamine showed β-arrestin2 recruitment at β1-AR. These results provide some clues for the potential action of β-AR drugs, and lay a foundation for the screening of β-arrestin-biased β-AR ligands.
Topics: Humans; beta-Arrestin 2; HEK293 Cells; Adrenergic beta-Agonists; Isoproterenol; Receptors, Adrenergic, beta-2; Norepinephrine
PubMed: 36594387
DOI: No ID Found -
ACS Omega Aug 2022Finding antivirals for SARS-CoV-2 is still a major challenge, and many computational and experimental approaches have been employed to find a solution to this problem....
Finding antivirals for SARS-CoV-2 is still a major challenge, and many computational and experimental approaches have been employed to find a solution to this problem. While the global vaccination campaigns are the primary driver of controlling the current pandemic, orally bioavailable small-molecule drugs and biologics are critical to overcome this global issue. Improved therapeutics and prophylactics are required to treat people with circulating and emerging new variants, addressing severe infection, and people with underlying or immunocompromised conditions. The SARS-CoV-2 envelope spike is a challenging target for viral entry inhibitors. Pindolol presented a good docking score in a previous virtual screening using computational docking calculations after screening a Food and Drug Administration (FDA)-approved drug library of 2400 molecules as potential candidates to block the SARS-CoV-2 spike protein interaction with the angiotensin-converting enzyme 2 (ACE-2). Here, we expanded the computational evaluation to identify five beta-blockers against SARS-CoV-2 using several techniques, such as microscale thermophoresis, NanoDSF, and assays in different cell lines. These data identified carvedilol with a of 364 ± 22 nM for the SARS-CoV-2 spike and activity (EC of 7.57 μM, CC of 18.07 μM) against SARS-CoV-2 in Calu-3 cells. We have shown how we can apply multiple computational and experimental approaches to find molecules that can be further optimized to improve anti-SARS-CoV-2 activity.
PubMed: 35983371
DOI: 10.1021/acsomega.2c01707 -
Translational Psychiatry Apr 2019Developing positron emission tomography (PET) radioligands for the detection of endogenous serotonin release will enable the investigation of serotonergic deficits in... (Randomized Controlled Trial)
Randomized Controlled Trial
Developing positron emission tomography (PET) radioligands for the detection of endogenous serotonin release will enable the investigation of serotonergic deficits in many neuropsychiatric disorders. The present study investigates how acute challenges that aim to increase or decrease cerebral serotonin levels affect binding of the serotonin 2A receptor (5-HTR) agonist radioligand [C]Cimbi-36. In a randomized, double-blind, placebo-controlled, three-arm design, 23 healthy volunteers were PET scanned twice with [C]Cimbi-36: at baseline and following double-blind assignment to one of three interventions (1) infusion of the selective serotonin reuptake inhibitor (SSRI) citalopram preceded by oral dosing of the 5-HTR antagonist pindolol, (n = 8) (2) acute tryptophan depletion (ATD) (n = 7) and (3) placebo (n = 8). Two-sample t-tests revealed no significant group differences in percent change of neocortical [C]Cimbi-36 binding from baseline to intervention between placebo and citalopram/pindolol (p = 0.4) or between placebo and ATD (p = 0.5). Notably, there was a significantly larger within-group variation in 5-HTR binding after intervention with citalopram/pindolol, as compared with placebo (p = 0.007). These findings suggest that neither ATD nor a combination of citalopram and pindolol elicit acute unidirectional changes in serotonin levels sufficient to be detected with [C]Cimbi-36 PET in neocortex. We suggest that the large interindividual variation in 5-HTR binding after citalopram/pindolol reflects that after an acute SSRI intervention, individuals respond substantially different in terms of their brain serotonin levels. Our observation has a potential impact for the understanding of patient responses to SSRI.
Topics: Benzylamines; Brain; Carbon Radioisotopes; Citalopram; Double-Blind Method; Female; Healthy Volunteers; Humans; Male; Phenethylamines; Pindolol; Positron-Emission Tomography; Serotonergic Neurons; Serotonin; Selective Serotonin Reuptake Inhibitors; Synaptic Transmission; Young Adult
PubMed: 30975977
DOI: 10.1038/s41398-019-0468-8 -
Journal of Chromatographic Science Aug 2023An azobenzenediamide bridged bis(β-cyclodextrin) chiral stationary phase (AZCDP) was prepared, and its high-performance liquid chromatography performance in...
An azobenzenediamide bridged bis(β-cyclodextrin) chiral stationary phase (AZCDP) was prepared, and its high-performance liquid chromatography performance in reversed-phase and polar organic modes was evaluated by chiral probes, including triazoles, flavanones, amino acids and β-blockers. The results showed that AZCDP had strong chiral separation ability and the 40 chiral compounds were successfully resolved, of which 32 were completely separated (Rs ≥ 1.5) and the best enantioresolution was up to 3.93 within 20 min under a wide range of pH value and temperature. The separation ability of AZCDP with double cavities was significantly better than common CD-CSPs with single cavity, which was related to the synergistic inclusion effect. Compared with the previously reported stilbene (C=C)-bridged CSP, AZCDP with azobenzene (N=N)-bridged had a wider resolution range. For example, it could resolve myclobutanil, pindolol, carteolol, betaxolol, bevanolol and bitertanol, which could not be resolved before, and should be related to the fact that the flexible N=N was more compatible with the synergistic inclusion between cavities than the rigid C=C bridge group. The azobenzenediamide bridging group could also provide hydrogen bond, π-π and other sites, which was conducive to chiral separations.
PubMed: 35726164
DOI: 10.1093/chromsci/bmac050 -
Behavioural Brain Research Jan 2019The effects of the 5-HT receptor blocker pindolol and the 5-HT releasing and uptake blocking agent d-fenfluramine, both used as indirect serotonin agonists, on... (Randomized Controlled Trial)
Randomized Controlled Trial
The effects of the 5-HT receptor blocker pindolol and the 5-HT releasing and uptake blocking agent d-fenfluramine, both used as indirect serotonin agonists, on flumazenil-induced acute anxiety reactions were studied in panic disorder patients to test the hypothesis that serotonin (5-HT) inhibits neural systems mediating panic attacks. Thirty never treated or drug free PD patients (16 females) aged 22-49 y (mean ± SD, 32.9 ± 8) received single doses of d-fenfluramine (n = 10; 30 mg, p.o.), pindolol (n = 10; 5 mg, p.o.), or placebo (n = 10) 90 and 45 min before a challenge test with flumazenil (1.5 mg, i.v., in 10 min), under double-blind conditions. Panic attacks occurred in 5 control subjects (placebo-flumazenil group), 5 subjects in the pindolol group and in 7 in the d-fenluramine pre-treated patients. Patients experiencing anxiety attacks following flumazenil reported higher increases in anxiety scores. Respiratory rate increases were not different between patients experiencing or not a panic attack. Despite sample size limitation, this study suggests that flumazenil induced anxiety reaction is not a good pharmacological model of panic attacks, considering the absence of serotonergic modulation of its effects.
Topics: Adult; Anxiety; Female; Fenfluramine; Flumazenil; GABA Modulators; Humans; Male; Middle Aged; Panic Disorder; Pindolol; Psychiatric Status Rating Scales; Regression Analysis; Serotonin Antagonists; Selective Serotonin Reuptake Inhibitors; Young Adult
PubMed: 29113874
DOI: 10.1016/j.bbr.2017.11.002 -
Frontiers in Pharmacology 2020Over recent years, pigs have been promoted as potential animal model due to their anatomical and physiological similarities with humans. However, information about the...
Over recent years, pigs have been promoted as potential animal model due to their anatomical and physiological similarities with humans. However, information about the contribution of distinct renal elimination processes [glomerular filtration rate (GFR), effective renal plasma flow (ERPF), tubular secretion, and reabsorption] in pigs is currently limited. Therefore, a cocktail of renal markers, consisting of iohexol (GFR), para-aminohippuric acid (ERPF and net tubular anion secretion), pindolol (net tubular cation secretion), and fluconazole (net tubular reabsorption) was administered intravenously to 7-week-old male conventional pigs. Plasma and urinary concentrations were determined using validated analytical methods. The clearance of iohexol (GFR) was 97.87 ± 16.05 ml/min/m² (mean ± SD). The ERPF, calculated as the renal clearance of PAH, was 226.77 ± 62.45 ml/min/m², whereas the net tubular secretion of PAH was 130.28 ± 52.62 ml/min/m². The net tubular secretion of R-pindolol and S-pindolol was 13.53 ± 12.97 and 18.01 ± 39.23 ml/min/m², respectively. The net tubular reabsorption of fluconazole was 78.32 ± 13.52 ml/min/m². Overall, this cocktail of renal markers was considered to be safe for use in pigs since no adverse effects were observed. Iohexol, PAH and fluconazole were considered suitable renal marker to assess the porcine renal function. Pindolol seems less appropriate due to the high degree of nonrenal clearance in pigs. The values of GFR, ERPF, and anion secretion are within the same range for both human and pig. Regarding the tubular reabsorption of fluconazole, slightly higher values were obtained for pigs. Nevertheless, these results indicate the conventional pig could be an appropriate animal model to study renal drug elimination processes in humans.
PubMed: 32595506
DOI: 10.3389/fphar.2020.00883