Adrenergic Agonists Research Articles

Long-term application of adrenergic agonists modulates nociceptive ion channels

Dorsal root ganglia (DRG) neurons transduce and convey somatosensory information from the periphery to the central nervous system. Adrenergic mediators are known to modulate nociceptive inputs in DRG neurons, acting as up- or down-regulators of neuronal excitability. They are also important in the development of sympathetic neuropathy. ATP-activated P2X channels and capsaicin-activated TRPV1 channels are directly involved in the transduction of nociceptive stimuli. In this work, we show that long-term (up to 3 days) in vitro stimulation of DRG neurons with selective α1-adrenergic agonist increased slow but not fast ATP-activated currents, with no effect on capsaicin currents. Selective agonists for α2, β1 and β3-adrenergic receptors decreased capsaicin activated currents and had no effect on ATP currents. Capsaicin currents were associated with increased neuronal excitability, while none of the adrenergic modulators produced change in rheobase. These results demonstrate that chronic adrenergic activation modulates two nociceptive transducer molecules, increasing or decreasing channel current depending on the adrenergic receptor subtype. These observations aid our understanding of nociceptive or antinociceptive effects of adrenergic agonists.

Xylazine-Associated Wounds and Related Health Concerns Among People Who Use Drugs: Reports From Front-Line Health Workers in 7 US States.

Xylazine, an adrenergic alpha-2 agonist increasingly present in the US drug supply, is associated with severe skin ulcers and other harms. Expert knowledge from front-line harm reduction and healthcare professionals is an essential component of evidence-based practice. The purpose of this study is to describe the progression and treatment of xylazine-associated wounds, other xylazine-related health concerns, and the most urgent research priorities as reported by front-line harm reduction and healthcare professionals serving people who use drugs. A convenience sample of 17 healthcare and harm reduction professionals who serve people who use drugs in the US states of Maryland, Massachusetts, Michigan, Minnesota, North Carolina, Pennsylvania, and Texas participated in semi-structured interviews. Participants were asked about the appearance and progression of xylazine-associated wounds; preferred treatment strategies; other xylazine-related harms experienced by people who use drugs; and the most urgent priorities for xylazine-related research. Xylazine-associated wounds were broadly described as small lesions appearing mostly on extremities both at and away from injection sites, often within hours or days of exposure, that quickly developed into large, complex, chronic wounds. Reported risk of secondary infection was generally low but appeared more common among unhoused populations. Most participants preferred conservative treatment strategies that included regular wound care, enzymatic debridement, and hygiene. Xylazine-associated wounds and xylazine withdrawal reportedly act as significant barriers to care, including addiction treatment. Participants reported urgent need for scientific research and evidence-based guidance on the management of xylazine-associated wounds and withdrawal. High-quality scientific evidence on risk factors for xylazine-associated wounds and on their biologic mechanisms is needed. Such studies could inform new strategies for the prevention and treatment of these wounds. Efforts to improve the management of xylazine withdrawal and to reduce stigma by incorporating harm reduction professionals into healthcare settings may improve access to and retention in care.

Dysfunctional Bladder Morphology and Functional Impairments Are Identified in the Alzheimer's Disease APPNL-G-F/NL-G-F Murine Model.

While symptoms related to lower urinary tract dysfunction (LUTD) are common in individuals with Alzheimer's disease (AD), pathophysiological links between AD and LUTD remain unclear. This study aimed to investigate whether AD neuropathology would cause autonomic dysfunction along the spinal cord-bladder axis, which could result in alterations in bladder muscle kinetics. We utilized APPNL-G-F/NL-G-F knock-in (APP KI) and APPwt/wt (wild-type) mice at two different ages, 4- and 10-month-old, to investigate how AD impacts bladder tissue function by immunohistochemistry, western blotting, and pharmacomyography. We showed that the mucosal layer partially separated from the detrusor in 10-month-old APP KI mouse bladders. Although there was no detectable amyloid deposition in the APP KI bladder, we found amyloid plaques in APP KI lumbar spinal cord. Further immunoblot analysis revealed that tyrosine hydroxylase protein levels were significantly reduced in both 4- and 10-month-old bladder tissues, suggesting reduction of norepinephrine synthesis in APP KI mouse bladders. In contrast, the level of β2 adrenergic receptor was increased in 4-month-old but not 10-month-old APP KI bladders. In bladder strips, the adrenergic agonist isoproterenol induced increased relaxation in 4- but not 10-month-old APP KI bladders. With 10 Hz electrical field stimulation, 10-month-old APP KI bladder strips were more responsive than wild-type controls, with no differences observed in 4-month-old APP KI bladders. APP KI mice exhibit LUTD, which is likely arising from amyloid pathology in the spinal cord, and results in maturational declines in presynaptic activity combined with compensatory postsynaptic upregulation.

Interaction between Nuclear Receptor and Alpha-Adrenergic Agonist Subtypes in Metabolism and Systemic Hemodynamics of Spontaneously Hypertensive Rats.

Partial and full PPAR-γ agonists have shown promising effects and antihypertensive and antidiabetic agents through increased plasma adiponectin concentration. This study is aimed at examining the role of PPAR-γ, alpha-adrenoceptors, and adiponectin receptors in the modulation of vasopressor responses to angiotensin II (Ang II) and adrenergic agonists, after a subset treatment of partial and full PPAR-γ agonists, each individually, and also when coupled with adiponectin in SHRs. The antioxidant potential and metabolic indices for these animals were also determined. Group I (WKY) and group II (SHR) were designated as normotensive control and hypertensive control, respectively. Groups III (SHR) and IV (SHR) received irbesartan (30 mg/kg) and pioglitazone (10 mg/kg) orally for 28 days, and groups V (SHR), VI (SHR), and VII (SHR) were treated with adiponectin (2.5 μg/kg) intraperitoneally alone, in combination with irbesartan, and in combination with pioglitazone, respectively, from days 21 to 28 only. On day 29, sodium pentobarbitone (60 mg/kg) was used to anesthetize all test animals, and systemic hemodynamic and plasma adiponectin concentrations and in vitro and in vivo antioxidant potential were measured. As compared to the WKY control, the SHR control group's noninvasive blood pressure and basal mean arterial pressure were significantly greater, along with increased arterial stiffness, lower plasma nitric oxide, adiponectin concentration, and antioxidant enzyme levels (all P < 0.05). However, they were gradually normalized by single drug treatments in all groups, and to a greater extent in the SHR + Irb + Adp group (P < 0.05). In the acute study, the dose dependant mean arterial pressure responses to intravenously administered adrenergic agonists and angiotensin-II were significantly larger in SHRs as compared to WKY by 20-25%. Adiponectin alone and in combination significantly blunted vasopressor responses to these alpha-adrenergic agonists in the SHR + Pio + Adp group by 63%, whereas attenuated responses to ANG-II administration to 70% in SHR + Irb + Adp. In conclusion, the combined treatment of adiponectin with PPAR-agonists reduced the systemic vascular responses to adrenergic agonists and improved arterial stiffness. This an evidence of the interaction of adiponectin receptors, PPAR-γ, alpha-adrenoceptors, and ANG-II in the systemic vasculature of SHRs. A significant level of synergism has also been proved among full PPAR-γ agonists and adiponectin receptors.

Treatment modalities for paediatric functional daytime lower urinary tract disorders: an updated review.

Paediatric functional bladder disorders especially those causing daytime symptoms are a common cause of significant psychosocial and/or physical morbidity and impaired quality of life. Despite the availability of many therapeutic modalities, a significant number of children appear to be refractory to treatment and continue to have symptoms. In this review, we aim to evaluate the current evidence in the use of existing and novel therapeutic options for the management of daytime lower urinary tract disorders in children. We also aim to highlight the controversies around the terminology and diagnosis of paediatric lower urinary tract dysfunction (LUTD) and specific conditions. The article will then provide a reasonable critique of the existing and emerging treatment modalities in functional daytime LUTD in children including their mode of action, efficacy, indications, and recent advances. These include standard urotherapy, specific urotherapy comprised of biofeedback, alarm therapy and electrical neural stimulation and pharmacotherapy involving selective and non-selective anticholinergics, ß3 adrenergic agonists, alpha blockers and botulinum toxin. A better understanding of this common clinical problem may help clinicians achieve better profiling of these children's diagnoses to further enable specific, targeted treatment.

Safety and efficacy of beta-3 adrenergic agonists in treating neurogenic lower urinary tract dysfunction: A systematic review and meta-analysis.

To evaluate efficacy and safety of beta-3 adrenergic agonists in adults with neurogenic lower urinary tract dysfunction. According to a protocol (CRD42022350079), we searched multiple data sources for published and unpublished randomized controlled trials (RCTs) up to 2nd August 2022. Two review authors independently screened studies and abstracted data from the included studies. We performed statistical analyses by using a random-effects model and interpreted them according to the Cochrane Handbook for Systematic Reviews of Interventions. We used GRADE guidance to rate the certainty of evidence (CoE). We found data to inform two comparisons: beta-3 adrenergic agonists versus placebo (4 RCTs) and anticholinergics (2 RCTs). Only mirabegron was used for intervention in all included studies. Compared to placebo, beta-3 adrenergic agonists may have a clinically unimportant effect on urinary symptoms score (mean difference [MD] -2.50, 95% confidence interval [CI] -4.78 to -0.22; I²=92%; 2 RCTs; 192 participants; low CoE) based on minimal clinically important difference of 3. We are very uncertain of the effects of beta-3 adrenergic agonists on quality of life (MD 10.86, 95% CI 1.21 to 20.50; I²=41%; 2 RCTs; 98 participants; very low CoE). Beta-3 adrenergic agonists may result in little to no difference in major adverse events (cardiovascular adverse events) (risk ratio 0.57, 95% CI 0.14 to 2.37; I²=0%; 4 RCTs; 310 participants; low CoE). Compared to anticholinergics, no study reported urinary symptom scores and quality of life. There were no major adverse events (cardiovascular adverse events) in either study group (1 study; 60 participants; very low CoE). Compared to placebo, beta-3 adrenergic agonists may have similar effects on urinary symptom scores and major adverse events. There were uncertainties about their effects on quality of life. Compared to anticholinergics, we are either very uncertain or have no evidence about urinary symptom scores, quality of life, and major adverse events.

Safety and Efficacy of Nebulised Dexmedetomidine as an Adjuvant to Topical Anaesthesia in Patients Undergoing Endobronchial Ultrasound under Moderate Sedation: A Randomised Double-blinded Controlled Study

Introduction: Anaesthetic sedatives are widely used for bronchoscopy and Endobronchial Ultrasound (EBUS) to ensure patient cooperation and minimise patient discomfort. Dexmedetomidine is an α2 adrenergic agonist used for sedation. Aim: To evaluate the safety and efficacy of nebulised dexmedetomidine in EBUS. Materials and Methods: In this randomised doubleblinded controlled study, conducted in the Department of Anaesthesiology and Pulmonary Medicine at Sher-i-Kashmir Institute of Medical Sciences, Srinagar, Jammu and Kashmir, India from 2020 to 2022, 52 patients aged between 18 and 70 years undergoing EBUS were included. Patients were randomly assigned to the study group (S) and the control group (C). Group C received nebulised lidocaine (2%) 10 mL for 10- 15 minutes in a sitting position. Group S received nebulised lidocaine (2%) 8 mL + Dexmedetomidine 2 mL (1 mcg/kg) for 10-15 minutes in a sitting position. Haemodynamic parameters, cough severity scores, patient and operator satisfaction scores, Midazolam requirements, and any complications were recorded and compared. The data were analysed statistically using the Student’s t-test and Chi-square test, whichever was feasible. A p-value of &lt;0.05 was considered statistically significant. Results: The demographic parameters including the mean age (years) of 46.3±14.01 in Group C vs. 44.5±14.35 in Group S, mean weight (kg) of 61.6±8.27 in Group C vs. 63.5±10.06 in Group S, and male/female ratio of 12/14 in Group C vs. 9/17 in Group S were comparable. Haemodynamic parameters were better postnebulisation in Group S compared to Group C. The authors observed that the incidence of coughing was significantly higher in Group C compared to Group S (73.1% vs. 46.2%). It was found that Group C had a significantly higher requirement for midazolam doses compared to Group S (53.8% vs. 19.2%). When the patient satisfaction score assessed on the Numerical Rating Scale (NRS) was analysed, it was found that Group S patients were highly satisfied compared to Group C patients, and the difference was highly significant (p-value &lt;0.05). No drug or procedure-related complications were observed in the two groups. Conclusion: The present study demonstrated that nebulised dexmedetomidine-lidocaine was well-tolerated during bronchoscopies under moderated sedation and was associated with stable Haemodynamics, decreased incidence of severe coughing, and a lower consumption of sedation drugs.

Formulation Development and Evaluation of Highly Oxidative Degradative Drug Molecule Injectable Dosage form by Lyophilisation Techniques

Adrenaline (ADR) It is lifesaving and is the only first-line drug for the treatment of anaphylaxis. Adrenaline (ADR) is the endogenous catecholamine with potent alpha- and beta-adrenergic stimulating properties. Alpha-adrenergic action increases systemic and pulmonary vascular resistance, increasing both systolic and diastolic blood pressure. Adrenaline is released in the bloodstream, which increases heartbeat, muscle strength, blood pressure, and glucose metabolism. Oxidation degradation of the medicinal product is the main route of degradation. Affects chemical and physical changes in drugs during the formulation development process. Physicochemical changes in the product can affect both the safety and efficacy of the drug product. Main product development strategy to develop, a stable, freeze-dried product of epinephrine for injection. The stability of adrenaline injection is of paramount objective as it is classified as a catechol compound that is sensitive to oxidation to o-quinone and therefore can react further to form highly colored compounds. Adrenergic drugs further react to form adrenochrome, a highly colored indole derivative. The rate of this reaction increased with pH, temperature and presence of the metal ions. Aqueous solutions of adrenergic agonists decompose rapidly when exposed to air, light, or heat, turning pink due to oxidation to adrenochrome and brown due to melanin formation. Due to its strong oxidizing properties and easy decomposition in aqueous solutions. To achieve this, the aqueous solutions of adrenergic agonists decompose rapidly when exposed to air, light, or heat, turning pink due to oxidation to adrenochrome and brown due to melanin formation. Due to its strong oxidizing properties and easy decomposition in aqueous solutions.

Simultaneous quantification of mirabegron and vibegron in human plasma by HPLC-MS/MS and its application in the clinical determination in patients with tumors associated with overactive bladder

Mirabegron and vibegron, both newly identified beta-3 adrenergic agonists, have significantly improved the quality of life for patients suffering from overactive bladder. In order to comprehensively assess the plasma exposure levels of these agents, the development of a rapid and highly sensitive bioanalytical method becomes imperative. The primary objective of this study was to establish a robust high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method for the concurrent quantification of mirabegron and vibegron in human plasma. The analytes were extracted from a 100 μL plasma sample through protein precipitation, employing 300 μL of methanol. Subsequently, samples underwent separation and quantification using a Waters XBridge C18 column (2.1 × 100 mm, 3.5 µm), with a mobile phase consisting of 0.1% formic acid in water and 0.1% formic acid in acetonitrile. The mass analysis was conducted using positive electrospray ionization (ESI+) operated in a multiple reaction monitoring (MRM) mode. The proposed method was meticulously validated in accordance with the guidelines set forth by the U.S. Food and Drug Administration (FDA) for bioanalytical method validation. The regression equations demonstrated exceptional linearity for both mirabegron (r² ≥ 0.994) and vibegron (r² ≥ 0.996) across the concentration range of 0.5 – 200 ng/mL. Furthermore, the assay exhibited accuracy (inter-day relative error ≤ 6.90%) and precision (inter-day coefficient of variation ≤ 8.88%). The average recoveries of the analytes were found to range from 81.94% to 102.02%, with mean matrix effects falling within the range of 89.77% to 110.58%. As a result, this method was deemed highly suitable for the precise determination of the concentrations of both mirabegron and vibegron in the context of therapeutic drug monitoring and bioequivalence studies.

Physicians' beliefs and perceived importance of traumatic brain injury-associated agitation in critically ill patients: a survey of Canadian intensivists.

Agitation is a common behavioural problem following traumatic brain injury (TBI). Intensive care unit (ICU) physicians' perspectives regarding TBI-associated agitation are unknown. Our objective was to describe physicians' beliefs and perceived importance of TBI-associated agitation in critically ill patients. Following current standard guidance, we built an electronic, self-administrated, 42-item survey, pretested it for reliability and validity, and distributed it to 219 physicians working in 18 ICU level-1 trauma centres in Canada. We report the results using descriptive statistics. The overall response rate was 93/219 (42%), and 76/93 (82%) respondents completed the full survey. Most respondents were men with ten or more years of experience. Respondents believed that pre-existing dementia (90%) and regular recreational drug use (86%) are risk factors for agitation. Concerning management, 91% believed that the use of physical restraints could worsen agitation, 90% believed that having family at the bedside reduces agitation, and 72% believed that alpha-2 adrenergic agonists are efficacious for managing TBI agitation. Variability was observed in beliefs on epidemiology, sex, gender, age, socioeconomic status, and other pharmacologic options. Respondents considered TBI agitation frequent enough to justify the implementation of management protocols (87%), perceived the current level of clinical evidence on TBI agitation management to be insufficient (84%), and expressed concerns about acute and long-term detrimental outcomes and burden to patients, health care professionals, and relatives (85%). Traumatic brain injury-associated agitation in critically ill patients was perceived as an important issue for most ICU physicians. Physicians agreed on multiple approaches to manage TBI-associated agitation although agreement on epidemiology and risk factors was variable.

Intranasal alpha-adrenergic receptor agonists and corticosteroids as medical treatments for nasal congestion

Nasal congestion has been a longstanding issue which exerts burdens on both individual patients and society as a whole. It arises from various underlying illnesses like nasal polyposis, rhinosinusitis, allergic rhinitis and rhinitis medicamentosa, but the fundamental mechanism of induced nasal congestion is nasal mucosas swelling as a result of inflammation in all of these cases. Among all the therapies currently available, intranasal sprays of alpha-adrenergic receptor agonists or corticosteroids appeared to be prominent options. After reviewing research on treatments extensively, limited studies focused on the comparison of -adrenergic agonists and corticosteroids. This research explores the mechanisms, efficacy, and safety of these two medical approaches. Intranasal alpha-adrenergic receptor agonist sprays target the smooth muscles for vasoconstriction, acting rapidly to give way to airflow. They are effective as a treatment for short-term nasal congestion, otherwise, continued use may lead to rhinitis medicamentosa. Corticosteroid sprays, on the other hand, aim to reduce the severity of nasal inflammation via suppression of pro-inflammatory molecules. They are a promising treatment barely with concerns about the occurrence of side effects, authenticated by their excellent pharmaceutical performance over years.

CardiOmics signatures reveal therapeutically actionable targets and drugs for cardiovascular diseases

Cardiovascular diseases are the leading cause of death worldwide, with heart failure being a complex condition that affects millions of individuals. Single-nucleus RNA sequencing has recently emerged as a powerful tool for unraveling the molecular mechanisms behind cardiovascular diseases. This cutting-edge technology enables the identification of molecular signatures, intracellular networks, and spatial relationships among cardiac cells, including cardiomyocytes, mast cells, lymphocytes, macrophages, lymphatic endothelial cells, endocardial cells, endothelial cells, epicardial cells, adipocytes, fibroblasts, neuronal cells, pericytes, and vascular smooth muscle cells. Despite these advancements, the discovery of essential therapeutic targets and drugs for precision cardiology remains a challenge. To bridge this gap, we conducted comprehensive in silico analyses of single-nucleus RNA sequencing data, functional enrichment, protein interactome network, and identification of the shortest pathways to physiological phenotypes. This integrated multi-omics analysis generated CardiOmics signatures, which allowed us to pinpoint three therapeutically actionable targets (ADRA1A1, PPARG, and ROCK2) and 15 effective drugs, including adrenergic receptor agonists, adrenergic receptor antagonists, norepinephrine precursors, PPAR receptor agonists, and Rho-associated kinase inhibitors, involved in late-stage cardiovascular disease clinical trials.

Beta-2 adrenergic receptor agonism alters astrocyte phagocytic activity and has potential applications to psychiatric disease

Schizophrenia is a debilitating condition necessitating more efficacious therapies. Previous studies suggested that schizophrenia development is associated with aberrant synaptic pruning by glial cells. We pursued an interdisciplinary approach to understand whether therapeutic reduction in glial cell—specifically astrocytic—phagocytosis might benefit neuropsychiatric patients. We discovered that beta-2 adrenergic receptor (ADRB2) agonists reduced phagocytosis using a high-throughput, phenotypic screen of over 3200 compounds in primary human fetal astrocytes. We used protein interaction pathways analysis to associate ADRB2, to schizophrenia and endocytosis. We demonstrated that patients with a pediatric exposure to salmeterol, an ADRB2 agonist, had reduced in-patient psychiatry visits using a novel observational study in the electronic health record. We used a mouse model of inflammatory neurodegenerative disease and measured changes in proteins associated with endocytosis and vesicle-mediated transport after ADRB2 agonism. These results provide substantial rationale for clinical consideration of ADRB2 agonists as possible therapies for patients with schizophrenia.

Noradrenergic regulation of cue-guided decision making and impulsivity is doubly dissociable across frontal brain regions

RationaleWin-paired stimuli can promote risk taking in experimental gambling paradigms in both rats and humans. We previously demonstrated that atomoxetine, a noradrenaline reuptake inhibitor, and guanfacine, a selective α2A adrenergic receptor agonist, reduced risk taking on the cued rat gambling task (crGT), a rodent assay of risky choice in which wins are accompanied by salient cues. Both compounds also decreased impulsive premature responding.ObjectiveThe key neural loci mediating these effects were unknown. The lateral orbitofrontal cortex (lOFC) and the medial prefrontal cortex (mPFC), which are highly implicated in risk assessment, action selection, and impulse control, receive dense noradrenergic innervation. We therefore infused atomoxetine and guanfacine directly into either the lOFC or prelimbic (PrL) mPFC prior to task performance.ResultsWhen infused into the lOFC, atomoxetine improved decision making score and adaptive lose-shift behaviour in males, but not in females, without altering motor impulsivity. Conversely, intra-PrL atomoxetine improved impulse control in risk preferring animals of both sexes, but did not alter decision making. Guanfacine administered into the PrL, but not lOFC, also altered motor impulsivity in all subjects, though in the opposite direction to atomoxetine.ConclusionsThese data highlight a double dissociation between the behavioural effects of noradrenergic signaling across frontal regions with respect to risky choice and impulsive action. Given that the influence of noradrenergic manipulations on motor impulsivity could depend on baseline risk preference, these data also suggest that the noradrenaline system may function differently in subjects that are susceptible to the risk-promoting lure of win-associated cues.

Study on the inhibition of dexmedetomidine (DEX) on malignant development of breast cancer by synchrotron radiation infrared spectroscopy

ObjectivesThe topic of the relationship between analgesia and cancer recurrence inoncology surgery is a subject of debate in the field. Administering analgesic drugs after breast cancer surgery could potentially impact the long-term outcomes for patients. During breast cancer surgery, DEX, a potent α2 adrenergic receptoragonist, is often administered as an analgesic. Despite its common use, the analgesic effect of DEX and its potential impact on the progression of breast cancer remain uncertain. MethodsTo investigate the impact of DEX on breast cancer cells, cells exposed to DEX were collected and analyzed through cell apoptosis detection and synchrotron radiation micro-infrared spectroscopy. ResultsFollowing DEX treatment, the absorption peaks of MDA-MB-231 and MCF-7 cell lines showed significant redshift at 1230–1250 cm−1 and 1380–1420 cm−1 bands (p<0.05). The absorption peak in the 1500–1700 cm−1 band decreased (p<0.05), while the 2910–2990 cm−1 absorption peak increased, along with other apoptotic characteristics (p<0.05). Our cell experiment results demonstrated that DEX was capable of protecting cell immunity via the down-regulation of TLR-4 receptor and effectively hindered the growth of breast cancer cells. ConclusionThe cell and spectrum experiments' results indicate that DEX can encourage tumor cell apoptosis. These findings suggest that DEX is safe to use for breast cancer surgery and pain management.

Possible Regulation of P-Glycoprotein Function by Adrenergic Agonists II: Study with Isolated Rat Jejunal Sheets and Caco-2 Cell monolayers

To clarify the regulation of drug absorption by the enteric nervous system, we investigated how adrenergic agonists (adrenaline (ADR), clonidine (CLO), dobutamine (DOB)) and dibutyryl cAMP (DBcAMP) affected P-glycoprotein (P-gp) function by utilizing isolated rat jejunal sheets and Caco-2 cell monolayers. ADR and CLO significantly decreased the secretory transport (Papptotal) of rhodamine-123 and tended to decrease the transport via P-gp (PappP−gp) and passive transport (Papppassive). In contrast, DBcAMP significantly increased and DOB tended to increase Papptotal and both tended to increase PappP−gpand Papppassive. Changes in P-gp expression on brush border membrane by adrenergic agonists and DBcAMP were significantly correlated with PappP−gp, while P-gp expression was not changed in whole cell homogenates, suggesting that the trafficking of P-gp would be responsible for its functional changes. Papppassive was inversely correlated with transmucosal or transepithelial electrical resistance, indicating that adrenergic agonists affected the paracellular permeability. Adrenergic agonists also changed cAMP levels, which were significantly correlated with PappP−gp. Furthermore, protein kinase A (PKA) or PKC inhibitor significantly decreased PappP−gp in Caco-2 cell monolayers, suggesting that they would partly contribute to the changes in P-gp activity. In conclusion, adrenergic agonists regulated P-gp function and paracellular permeability, which would be caused via adrenoceptor stimulation.

Personalized approach to pharmacotherapy of overactive bladder

The article provides an overview of modern approaches to pharmacotherapy of overactive bladder. It has been shown that the choice of drug therapy for overactive bladder should be made taking into account the pathophysiological mechanisms of the development of the disease, the characteristics of its clinical course, as well as the potential risks of developing side effects of treatment. A pathogenetic rationale for the choice of treatment tactics for different categories of patients is presented, including those with a hypersensitive bladder, bladder outlet obstruction, neurological and geriatric patients. The pharmacological properties of the β3-adrenergic receptor agonist mirabegron are described, which provide high efficacy and a favorable safety profile in the treatment of patients with overactive bladder. The practical issues of prescribing mirabegron in various clinical situations are considered.

Evaluation of the α&lt;sub&gt;2&lt;/sub&gt;-adrenergic Agonist Mafedine Effects on White Outbred Mouse Behaviour Following Acute Administration

Introduction. α2-adrenergic agonists are not only used as antihypertensive and sedative agents, but are also of interest as potential medications for the treatment of neurological disorders. Previous research has shown a compound from this class, 6-oxo-1-phenyl-2-(phenylamino)-1,6-dihydropyrimidine-4-ol (mafedine), to exert strong neuroprotection under experimental conditions. Despite its long record of development, the effects of mafedine on animal behavioural characteristics remain unknown.Aim. This work was aimed at evaluating the effects of mafedine sodium at three doses (1, 10, or 50 mg/kg) on white outbred mouse behavior in three tests: Open Field, Elevated Plus Maze, and Light/Dark Box.Materials and methods. Experiments were carried out on 60 white outbred male mice weighing 20–22 g, randomized into 4 groups (n = 15): 1) control (0,9 % saline); 2) mafedine (1 mg/kg); 3) mafedine (10 mg/kg); 4) mafedine (50 mg/kg). All agents were administered via single intraperitoneal injections 20 min before testing. Animal behavior was assessed using the Open Field, Elevated Plus Maze, and Light/Dark Box tests following conventional protocols with group reassignment between tests and an inter-test time interval of at least 2 days. Statistical analysis was carried out using the Prism 8.0.2 software package.Results and discussion. At 1 or 10 mg/kg, mafedine did not affect animal behaviour in either of the tests. At 50 mg/kg, it produced an anxiolytic effect, as indicated by the decrease in the anxiety index values for the Elevated Plus Maze test as well as the increase in peeking out frequency in the Light/Dark Box test, compared to respective control values.Сonclusion. Mafedine sodium salt at doses between 1 and 50 mg/kg was shown to produce no adverse effect on mouse behaviour, indicating a good safety profile of the compound. The discovered anxiolytic effect of mafedine at the highest dose validates its further research not only as a neuroprotector, but also as an anti-anxiety agent.

Advances in Anesthesia for Shoulder Surgery: A Comprehensive Review of Dexmedetomidine-Enhanced Interscalene Brachial Plexus Block.

Surgical procedures on the shoulder pose distinctive challenges in managing pain during the perioperative period, underscoring the importance of exploring innovative anesthesia techniques. This comprehensive review article delves into integrating dexmedetomidine, an alpha-2 adrenergic agonist, within interscalene brachial plexus blocks for shoulder surgery. The review initiates by underscoring the pivotal role of effective anesthesia in shoulder surgery and elucidates the rationale behind investigating dexmedetomidine as an adjunct. It meticulously examines the anatomy and physiology of the brachial plexus, emphasizing its critical significance in shoulder surgery. Furthermore, the article expounds on dexmedetomidine's mechanisms of action and pharmacokinetics, encompassing its safety profile and potential side effects. The conventional interscalene brachial plexus block techniques, along with their limitations and challenges, are discussed, laying the foundation for the integration of dexmedetomidine. The review subsequently delves into exploring the role of dexmedetomidine in regional anesthesia, covering previous studies, mechanisms of action, and the potential advantages of incorporating it into nerve blocks. The review's core concentrates on the practical application of dexmedetomidine-enhanced interscalene brachial plexus blocks. This includes discussions on administration techniques, dosage guidelines, and compelling evidence supporting its utilization. Clinical scenarios where this approach proves most advantageous are thoroughly explored, comparing its effectiveness with traditional techniques in terms of pain control and patient outcomes. A comprehensive examination of relevant clinical trials and case studies highlights the evidence supporting its efficacy. The review also underscores safety considerations associated with dexmedetomidine. It proposes strategies for mitigating risks to ensure patient safety. Insights into future directions and research are provided, encompassing ongoing studies, areas necessitating further investigation, and potential refinements in technique. Finally, the article summarizes key findings, emphasizing the practicality of dexmedetomidine-enhanced interscalene brachial plexus blocks in shoulder surgery and its far-reaching implications for clinical practice and patient care.

β-adrenergic signaling triggers enteric glial reactivity and acute enteric gliosis during surgery

BackgroundEnteric glia contribute to the pathophysiology of various intestinal immune-driven diseases, such as postoperative ileus (POI), a motility disorder and common complication after abdominal surgery. Enteric gliosis of the intestinal muscularis externa (ME) has been identified as part of POI development. However, the glia-restricted responses and activation mechanisms are poorly understood. The sympathetic nervous system becomes rapidly activated by abdominal surgery. It modulates intestinal immunity, innervates all intestinal layers, and directly interfaces with enteric glia. We hypothesized that sympathetic innervation controls enteric glia reactivity in response to surgical trauma.MethodsSox10iCreERT2/Rpl22HA/+ mice were subjected to a mouse model of laparotomy or intestinal manipulation to induce POI. Histological, protein, and transcriptomic analyses were performed to analyze glia-specific responses. Interactions between the sympathetic nervous system and enteric glia were studied in mice chemically depleted of TH+ sympathetic neurons and glial-restricted Sox10iCreERT2/JellyOPfl/+/Rpl22HA/+ mice, allowing optogenetic stimulation of β-adrenergic downstream signaling and glial-specific transcriptome analyses. A laparotomy model was used to study the effect of sympathetic signaling on enteric glia in the absence of intestinal manipulation. Mechanistic studies included adrenergic receptor expression profiling in vivo and in vitro and adrenergic agonism treatments of primary enteric glial cell cultures to elucidate the role of sympathetic signaling in acute enteric gliosis and POI.ResultsWith ~ 4000 differentially expressed genes, the most substantial enteric glia response occurs early after intestinal manipulation. During POI, enteric glia switch into a reactive state and continuously shape their microenvironment by releasing inflammatory and migratory factors. Sympathetic denervation reduced the inflammatory response of enteric glia in the early postoperative phase. Optogenetic and pharmacological stimulation of β-adrenergic downstream signaling triggered enteric glial reactivity. Finally, distinct adrenergic agonists revealed β-1/2 adrenoceptors as the molecular targets of sympathetic–driven enteric glial reactivity.ConclusionsEnteric glia act as early responders during post-traumatic intestinal injury and inflammation. Intact sympathetic innervation and active β-adrenergic receptor signaling in enteric glia is a trigger of the immediate glial postoperative inflammatory response. With immune-activating cues originating from the sympathetic nervous system as early as the initial surgical incision, adrenergic signaling in enteric glia presents a promising target for preventing POI development.