The alpha-7 nicotinic acetylcholine receptor agonist PHA-543613 reduces food intake in male rats

Obesity is a prevalent disease, but effective treatment options remain limited. Agonists of the alpha-7 nicotinic acetylcholine receptor (α7nAChR) promote negative energy balance in mice, but these effects are not well-studied in rats. We tested the hypothesis that central administration of the α7nAChR agonist PHA-543613 (PHA) would decrease food intake and body weight in adult male Sprague Dawley rats. Intracerebroventricular (ICV) PHA administration in chow-fed rats produced a suppression of energy intake and weight gain over 24 h. Next, to evaluate effects of ICV PHA on palatable food intake, rats were maintained on a choice diet of rodent chow and 45 % high fat diet (HFD); under these conditions, ICV PHA produced no significant changes in energy intake from either food, or body weight gain, in the 24 h post-injection. However, when given a choice of chow or a higher-fat 60 % HFD, ICV PHA reduced intake of 60 % HFD, but not chow; body weight gain was also suppressed. Further experiments evaluating conditioned taste avoidance (CTA) and pica in response to ICV PHA suggested that the suppressive food intake and body weight effects after ICV injection of PHA were not due to nausea/malaise. Finally, an operant conditioning study showed that responding on a progressive ratio schedule of reinforcement for high-fat food pellets decreased after ICV PHA. Collectively, these studies show that PHA reduces energy intake under some but not all dietary conditions. Importantly, central PHA decreases both food intake as well as motivation for highly palatable, energy dense foods in rats without inducing nausea/malaise, suggesting that the α7nAChR could be a viable target for developing treatments for obesity.

Post-treatment with maropitant reduces oxidative stress, endoplasmic reticulum stress and neuroinflammation on peripheral nerve injury in rats

OBJECTIVE

To determine the effective dose and therapeutic potential of maropitant using through expression of mediators of oxidative stress, inflammatory and of the unfolded protein response (UPR) (bio) markers on spinal cord using a model of neuropathic pain induced through chronic constriction injury (CCI) in rats.

STUDY DESIGN

Randomized, blinded, prospective experimental study.

ANIMALS

98 male Wistar rats.

METHODS

Rats were anesthetized with sevoflurane and after CCI, they were randomly assigned to the following groups that received: vehicle, 3, 6, 15, 30 e 50 mg/kg/24q of maropitant. The effect on inflammatory mediators (IL10, TNFα), oxidative stress (GPx, CAT, SOD), microglial (IBA-1) and neuronal (NeuN, TACR1) markers was evaluated though immunohistochemistry and expression levels of markers of hypoxia (HIF1α, Nrf2), antioxidant enzymes (Catalse, Sod1 and GPx1), and endoplasmic reticulum stress mediators (GRP78, CHOP and PERK) through qRT-PCR.

RESULTS

Intraperitoneal injection (IP) of maropitant inhibited nociception with ID50 values of 4,1 mg/kg (5,85-19,36) in a neuropathic pain model through CCI. A dose of 30 mg/kg/24q was significantly effective in reducing mechanical allodynia 1 to 4h after treatment with nociception inhibition (145,83%). A reduction in the expression of hypoxia factors (HIF1α, Nrf2) was observed, along with an increase in antioxidant activity (CAT, SOD and GPX). Additionally, there was a reduction in inflammatory markes (IL10, TNFα), microglial (IBA-1), and neuronal markers (NeuN, TACR1).

CONCLUSION AND CLINICAL RELEVANCE

These findings demonstrate that the determined dose, administered daily for seven days, had an antinociceptive effect, as well as anti-inflammatory and antioxidant activity.

Does maropitant provide more effective perioperative pain management than meloxicam in bitches undergoing ovariohysterectomy? The first report on the comparison of visceral algesia-analgesia for ovariohysterectomy

Ovariohysterectomy (OVH) is a widely used surgical procedure in small animal practice. In developing countries, injectable anesthetics such as ketamine and xylazine are commonly used in veterinary medicine. Pharmacological agents with analgesic activity, such as ketamine and meloxicam, are not sufficiently effective in reducing visceral pain. Therefore, this study aimed to investigate the visceral analgesia and anti-inflammatory effectiveness of maropitant compared with those of meloxicam during and after OVH in bitches. In this study, thirty-six bitches were randomly divided into the maropitant, meloxicam, and control groups. The heart rate (HR), peripheral oxygen saturation, and respiratory rate were monitored during the procedure. Pain scores were assessed using the University of Melbourne pain scale (UMPS). Rescue analgesia was not necessary for any bitch at any time point. Blood samples were collected before anesthesia induction and 24 h after the operation to determine C-reactive protein (CRP) levels. No significant difference was observed in HR between the control and meloxicam groups when the right ovary was removed, and the HR of the maropitant group was significantly (p < 0.05) lower than that of the control group. The pain scores of the maropitant group were significantly (p < 0.05) lower than those of the other groups. However, no significant differences were observed in CRP levels between the groups. In conclusion, compared to meloxicam, maropitant provided more effective visceral analgesia in bitches undergoing OVH, although no significant difference was found in its anti-inflammatory effect.

Outcomes of Patients with COPD Treated with ICS/LABA Before and After Initiation of Single-Inhaler Triple Therapy with Fluticasone Furoate/Umeclidinium/Vilanterol (FF/UMEC/VI)

INTRODUCTION

Triple therapy (fluticasone furoate/umeclidinium/vilanterol; FF/UMEC/VI) has been shown to improve symptoms and reduce exacerbations in patients with chronic obstructive pulmonary disease (COPD) and a history of exacerbations. This real-world study compared exacerbation rates and healthcare resource utilization (HCRU) before and after initiation of FF/UMEC/VI in patients with COPD previously treated with inhaled corticosteroid (ICS)/long-acting β2-agonist (LABA).

METHODS

This retrospective cohort study included commercial and Medicare Advantage with Part D administrative claims data from September 01, 2016, to March 31, 2020, of patients diagnosed with COPD. The index date was the date of the first FF/UMEC/VI claim (September 2017-March 2019). The 12 months prior to index (baseline) were used to assess patient characteristics and outcomes; the 12 months following index (follow-up) were used to assess study outcomes. All patients had ≥ 30 consecutive days' supply of any ICS/LABA dual therapy during the 12 months prior to FF/UMEC/VI initiation. Subgroup analyses included patients with ≥ 30 consecutive days' supply of budesonide/formoterol (BUD/FORM) during baseline. Analyses of patients with ≥ 1 COPD exacerbation during baseline were reported as well.

RESULTS

The overall population included 1449 patients (mean age 70.75 years; 54.18% female), of whom 540 were patients in the BUD/FORM subgroup. Significantly fewer patients experienced any exacerbation during follow-up versus baseline (overall population 53.49% vs 62.59%; p < 0.001; BUD/FORM subgroup 55.00% vs 62.41%; p = 0.004). Effects on exacerbation reduction were more pronounced among patients with ≥ 1 exacerbation during baseline. Lower COPD-related HCRU was observed during the follow-up compared with baseline for both the overall population and the BUD/FORM subgroup.

CONCLUSION

Patients with COPD treated with ICS/LABA during baseline, including patients specifically treated with BUD/FORM and those with a history of ≥ 1 exacerbation, had fewer COPD exacerbations and lower COPD-related HCRU after initiating FF/UMEC/VI.

Inpatient Admissions and Re-Admissions in Medicare Beneficiaries Initiating Umeclidinium/Vilanterol or Tiotropium Therapy

Purpose

Patients with chronic obstructive pulmonary disease (COPD) who are hospitalized are more likely to die from their illness and have increased likelihood of re-admission than those who are not. Subsequent re-admissions further increase the burden on healthcare systems. This study compared inpatient admission rates and time-to-first COPD-related inpatient admission among Medicare beneficiaries with COPD indexed on umeclidinium/vilanterol (UMEC/VI) versus tiotropium (TIO).

Patients and Methods

This retrospective study used the All-Payer Claims Database to investigate hospital admission and re-admission outcomes in Medicare beneficiaries with COPD with an initial pharmacy claim for UMEC/VI or TIO from 1 January 2015 to 28 February 2020. Inpatient admissions, baseline, and follow-up variables were assessed in patients indexed on UMEC/VI and TIO after propensity score matching (PSM), with time-to-first on-treatment COPD-related inpatient admission as the primary endpoint. Re-admissions were assessed among patients with a COPD-related inpatient admission in the 30- and 90-days post-discharge.

Results

Post-PSM, 7152 patients indexed on UMEC/VI and 7069 on TIO were eligible for admissions analysis. The mean (standard deviation [SD]) time-to-first COPD-related inpatient admission was 46.71 (87.99) days for patients indexed on UMEC/VI and 44.96 (85.90) days for those on TIO (p=0.06). The mean (SD) number of inpatient admissions per patient was 1.24 (2.92) for patients indexed on UMEC/VI and 1.26 (3.05) for those on TIO (p=0.49). Proportion of patients undergoing re-admissions was similar between treatments over both 30 and 90 days, excluding a significantly lower proportion of patients indexed on UMEC/VI than those indexed on TIO for COPD-related re-admissions for hospital stays of 4-7 days and 7-14 days, and all-cause re-admissions for stays of 4-7 days.

Conclusion

Patients with COPD using Medicare in the US and receiving UMEC/VI or TIO reported similar time-to-first inpatient admission and similar proportion of re-admissions.

Real-World Effectiveness of Fluticasone Furoate/Umeclidinium/Vilanterol Once-Daily Single-Inhaler Triple Therapy for Symptomatic COPD: The ELLITHE Non-Interventional Trial

Purpose

Real-life effectiveness data on once-daily single-inhaler triple therapy (odSITT) with the inhaled corticosteroid fluticasone furoate (FF), the long-acting muscarinic antagonist umeclidinium (UMEC), and the long-acting β2-agonist vilanterol (VI) in patients with chronic obstructive pulmonary disease (COPD) are important to complement evidence from well-controlled randomized clinical trials. Effectiveness of odSITT was quantified by assessing health status and symptoms in usual care.

Patients and Methods

ELLITHE was a single-country (Germany), multicenter, open-label, non-interventional effectiveness study between 2020 and 2022, evaluating the effect of treatment initiation with FF/UMEC/VI 100/62.5/25 µg once-daily via the ELLIPTA inhaler on improvements in clinical outcomes versus baseline in COPD patients. The primary endpoint was the change in the total COPD Assessment Test (CAT) score between baseline and month 12. Key secondary endpoints included change in CAT score over time, occurrence of exacerbations until month 12, changes in forced expiratory volume in one second (FEV1), inhaler adherence, and safety.

Results

Nine hundred and six patients were included (age 66.6 years, 55.6% male, mean FEV1 52.6% of predicted, mean CAT 21.5 units, 1.4 exacerbations/year pre-study). About 63.9% of patients were escalated from dual therapies, and 18% were switched from multiple-inhaler triple therapies. Reductions in CAT score at month 12 were statistically significant and above the threshold of clinical importance (-2.6 units; p < 0.0001). CAT score also improved at interim visits. CAT improvements were more pronounced in patients with high baseline scores and better inhaler adherence. Exacerbations during follow-up were rare (0.2 events/year) compared to pre-study (1.4 events/year). FEV1 was improved by 93 mL (p < 0.0001). No new safety effects were observed.

Conclusion

In usual care, treatment with odSITT resulted in significant and clinically relevant improvements of CAT score and FEV1 in COPD patients, regardless of the occurrence of exacerbations. These findings challenge the current guideline recommendations for SITT only in patients experiencing exacerbations.

Outcomes Following Initiation of Triple Therapy with Fluticasone Furoate/Umeclidinium/Vilanterol versus Multiple-Inhaler Triple Therapy Among Medicare Advantage with Part D Beneficiaries and Those Commercially Enrolled for Health Care Insurance in the United States

Purpose

Patients with chronic obstructive pulmonary disease (COPD) have been shown to benefit from triple therapy commonly delivered by multiple-inhaler triple therapy (MITT); however, the complexity of MITT regimens may decrease patient adherence. Fluticasone furoate/umeclidinium/vilanterol (FF/UMEC/VI), a once-daily single-inhaler triple therapy (SITT), became available in the United States (US) in 2017, but real-world data comparing outcomes for SITT versus MITT are currently limited. This study compared outcomes among patients with COPD initiating MITT versus SITT with FF/UMEC/VI who were either Medicare Advantage with Part D (MAPD) beneficiaries or commercial enrollees in the US.

Methods

Retrospective study using administrative claims data from the Optum Research Database for patients with COPD who initiated FF/UMEC/VI or MITT between September 1, 2017, and March 31, 2019 (index date: first pharmacy claim for FF/UMEC/VI cohort; earliest day of ≥30 consecutive days-long period of overlap in the day's supply of all triple therapy components for MITT cohort). COPD exacerbations, adherence to triple therapy, and all-cause and COPD-related health care resource utilization (HCRU) and costs were compared between FF/UMEC/VI and MITT initiators.

Results

In total, 4659 FF/UMEC/VI initiators and 9845 MITT initiators for the MAPD population, and 821 FF/UMEC/VI initiators and 1893 MITT initiators for the commercial population were included in the study. MAPD beneficiaries initiating FF/UMEC/VI had a significantly lower annual rate of severe exacerbations compared to MITT initiators (0.26 vs 0.29; p=0.014). They also had a significantly higher mean adherence (proportion of days covered) (0.51 vs 0.37; p<0.001) and significantly lower all-cause and COPD-related inpatient stays compared to MITT initiators ([32.02% vs 34.27%; p=0.017], [16.09% vs 17.72%; p=0.037]). Trends were similar among the commercial population, but the results were not statistically significant.

Conclusion

FF/UMEC/VI initiators had significantly fewer severe exacerbations, higher triple therapy adherence, and lower HCRU costs compared to MITT initiators for MAPD beneficiaries.

Changes in Oral Corticosteroid Utilization in Patients with COPD Following Initiation of FF/UMEC/VI

Purpose

Oral corticosteroids (OCS) play a role in the treatment of acute chronic obstructive pulmonary disease (COPD) exacerbations; however, chronic use is not recommended due to the high rate of systemic complications, development of comorbidities, and increased mortality. Data assessing the real-world impact of fluticasone furoate/umeclidinium/vilanterol (FF/UMEC/VI) on OCS utilization rates are limited. This study assessed the impact of FF/UMEC/VI on OCS use among patients with COPD previously treated with OCS.

Patients and Methods

A retrospective database study of patients with COPD aged ≥40 years who initiated FF/UMEC/VI from 1 November 2017 to 31 December 2018, identified through the MarketScan® Commercial and Medicare Supplemental databases. Patients were required to have ≥1 dispensing of an OCS prior to initiation of FF/UMEC/VI (index) and were followed up for 12 months post-index. OCS utilization patterns, potential OCS-related adverse events, healthcare resource utilization (HCRU), and costs were compared between the 12-month pre- and post-index periods.

Results

A total of 2013 patients were identified (mean age 63.5 years, 55.7% female). The proportion of patients with ≥1 OCS claim decreased by 32.2% between the pre- and post-index period (67.8% vs 100%; p < 0.001). Comparing the post-index period to the pre-index period, mean number of OCS pharmacy claims per patient decreased from 3.3 to 2.5 (p < 0.001) and mean daily dose was reduced from 3.1 to 2.6 mg/day (p = 0.004); 30.0% of patients reduced their daily dose by 90-100%. Reductions were also seen in COPD-related HCRU. The proportion of patients with an inpatient admission for COPD decreased from 11.4% to 7.1% (p < 0.001), emergency room visits decreased from 23.1% to 17.4% (p < 0.001), and office visits from 97.5% to 90.1% (p < 0.001). Similar results were seen for all-cause HCRU.

Conclusion

Among patients with COPD with prior OCS use, FF/UMEC/VI initiation resulted in significant reductions in OCS utilization, COPD-related HCRU (including hospitalization), and all-cause HCRU.

Single-dose NEPA versus an aprepitant regimen for prevention of chemotherapy-induced nausea and vomiting in patients receiving moderately emetogenic chemotherapy

INTRODUCTION

Non-inferiority of NEPA (fixed combination of NK1 receptor antagonist (RA), netupitant, and 5-HT3 RA, palonosetron) versus an aprepitant regimen was previously shown in a pragmatic study in patients receiving anthracycline cyclophosphamide (AC) and non-AC moderately emetogenic chemotherapy (MEC). In the MEC group a numerically higher complete response (CR: no emesis, no rescue) rate was seen for NEPA during the overall 0-120 h phase (NEPA 76.1% vs. 63.1% aprepitant). As NEPA exhibits long-lasting efficacy, this study evaluated a prolonged period up to 144 h, beyond the traditional 120 h post-chemotherapy. In this post-hoc analysis we explore the comparative efficacy of NEPA versus the aprepitant regimen in the MEC group up to 144 h, while also assessing the impact of risk factors on CINV prevention.

METHODS

This was a pragmatic, multicenter, randomized, prospective study. Oral NEPA was administered as a single dose on day 1, while aprepitant was given on days 1-3 + ondansetron on day 1; all patients were to receive dexamethasone on days 1-4. Patients were chemotherapy-naïve and receiving MEC, with a subset evaluation of those with a risk factor for developing CINV (i.e., female, male <60 years, male ≥60 years who received carboplatin, or male ≥60 years with anxiety). CR rates were compared during the extended overall (0-144 h) phase.

RESULTS

The MEC group included 211 patients; of these 181 were in the risk factor subset. Significantly higher CR rates were seen for NEPA than aprepitant during the extended overall phase for the total MEC group (NEPA 77.1%, aprepitant 57.8%, p = 0.003) and also in the subset of patients with CINV risk factors (NEPA 73.9%, aprepitant 56.2%, p = 0.012).

CONCLUSION

A single dose of NEPA, administered on day 1 only, was more effective than a 3-day aprepitant regimen in preventing CINV for an extended duration in patients receiving MEC and in those with emetic risk factors.

Comparison of Rescue Medication Prescriptions in Patients with Chronic Obstructive Pulmonary Disease Receiving Umeclidinium/Vilanterol versus Tiotropium Bromide/Olodaterol in Routine Clinical Practice in England

Purpose

Routinely collected healthcare data on the comparative effectiveness of the long-acting muscarinic antagonist/long-acting β2-agonist combination umeclidinium/vilanterol (UMEC/VI) versus tiotropium bromide/olodaterol (TIO/OLO) for chronic obstructive pulmonary disease (COPD) is limited. This study compared rescue medication prescriptions in patients with COPD in England receiving UMEC/VI versus TIO/OLO.

Patients and Methods

This retrospective cohort study used primary care data from the Clinical Practice Research Datalink Aurum database linked with secondary care administrative data from Hospital Episode Statistics. Patients with a COPD diagnosis at age ≥35 years were included (indexed) following initiation of single-inhaler UMEC/VI or TIO/OLO between July 1, 2015, and September 30, 2019. Outcomes included the number of rescue medication prescriptions at 12-months (primary), and at 6-, 18- and 24-months (secondary), adherence at 6-, 12-, 18- and 24-months post-index, defined as proportion of days covered ≥80% (secondary), and time-to-initiation of triple therapy (exploratory). Inverse probability of treatment weighting (IPTW) was used to balance potential confounding baseline characteristics. Superiority of UMEC/VI versus TIO/OLO for the primary outcome of rescue medication prescriptions was assessed using an intention-to-treat analysis with a p-value < 0.05.

Results

In total, 8603 patients were eligible (UMEC/VI: n = 6536; TIO/OLO: n = 2067). Following IPTW, covariates were well balanced across groups. Patients initiating UMEC/VI had statistically significantly fewer (mean [standard deviation]; p-value) rescue medication prescriptions versus TIO/OLO in both the unweighted (4.84 [4.78] vs 5.68 [5.00]; p < 0.001) and weighted comparison (4.91 [4.81] vs 5.48 [5.02]; p = 0.0032) at 12 months; consistent results were seen at all timepoints. Adherence was numerically higher for TIO/OLO versus UMEC/VI at all timepoints. Time-to-triple therapy was similar between treatment groups.

Conclusion

UMEC/VI was superior to TIO/OLO in reducing rescue medication prescriptions at 12 months after treatment initiation in a primary care cohort in England, potentially suggesting improvements in symptom control with UMEC/VI compared with TIO/OLO.

Increased p53 expression induced by APR-246 reprograms tumor-associated macrophages to augment immune checkpoint blockade

In addition to playing a major role in tumor cell biology, p53 generates a microenvironment that promotes antitumor immune surveillance via tumor-associated macrophages. We examined whether increasing p53 signaling in the tumor microenvironment influences antitumor T cell immunity. Our findings indicate that increased p53 signaling induced either pharmacologically with APR-246 (eprenetapopt) or in p53-overexpressing transgenic mice can disinhibit antitumor T cell immunity and augment the efficacy of immune checkpoint blockade. We demonstrated that increased p53 expression in tumor-associated macrophages induces canonical p53-associated functions such as senescence and activation of a p53-dependent senescence-associated secretory phenotype. This was linked with decreased expression of proteins associated with M2 polarization by tumor-associated macrophages. Our preclinical data led to the development of a clinical trial in patients with solid tumors combining APR-246 with pembrolizumab. Biospecimens from select patients participating in this ongoing trial showed that there was a suppression of M2-polarized myeloid cells and increase in T cell proliferation with therapy in those who responded to the therapy. Our findings, based on both genetic and a small molecule–based pharmacological approach, suggest that increasing p53 expression in tumor-associated macrophages reprograms the tumor microenvironment to augment the response to immune checkpoint blockade.

Effect of Recent Exacerbation History on the Efficacy of Once-Daily Single-Inhaler Fluticasone Furoate/Umeclidinium/Vilanterol Triple Therapy in Patients with Chronic Obstructive Pulmonary Disease in the FULFIL Trial

Background

In the FULFIL trial, once-daily single-inhaler triple therapy with fluticasone furoate/umeclidinium/vilanterol (FF/UMEC/VI) resulted in reduced moderate/severe exacerbation rates and conferred significant improvements in lung function and health status in patients with chronic obstructive pulmonary disease (COPD) versus twice-daily budesonide/formoterol (BUD/FOR) dual therapy.

Methods

FULFIL was a Phase III, randomized, double-blind, double-dummy, parallel-group study. Patients ≥40 years of age with symptomatic COPD were randomized 1:1 to FF/UMEC/VI 100/62.5/25 mcg or BUD/FOR 400/12 mcg. In this post hoc analysis, patients were categorized by exacerbation history in the year prior to study entry (≥1 moderate/severe exacerbation [recent exacerbation] versus no recent exacerbation). Endpoints included annual rate of on-treatment moderate/severe exacerbations up to Week 24, annual rate of on-treatment severe exacerbations up to Week 24, change from baseline in trough forced expiratory volume in 1 second at Week 24, and change from baseline in health status as measured by St George’s respiratory questionnaire total score at Week 24.

Results

Of the 1810 patients in the intent-to-treat population, 1180 (65%) had one or more moderate/severe exacerbation in the year prior to entry, while 630 (35%) patients did not. FF/UMEC/VI versus BUD/FOR significantly reduced moderate/severe exacerbation rates in the recent exacerbation subgroup (mean annualized rate: 0.19 vs 0.29; rate ratio [95% confidence interval [CI]]: 0.64: [0.45, 0.91]; p=0.014) and numerically reduced moderate/severe exacerbation rates in the no recent exacerbation subgroup (mean annualized rate: 0.29 vs 0.43; rate ratio [95% CI]: 0.67 [0.43, 1.04]; p=0.073). Severe exacerbation rates were numerically reduced with FF/UMEC/VI versus BUD/FOR treatment across both subgroups. FF/UMEC/VI conferred significant improvements in lung function and health status versus BUD/FOR, regardless of recent exacerbation history.

Conclusion

FF/UMEC/VI reduced moderate/severe and severe exacerbation rates and improved lung function and health status versus BUD/FOR in patients with symptomatic COPD, regardless of recent exacerbation history.

Determination of the embryotoxic effect of maropitant using an in ovo model

The aim of this research was to determine the embryotoxic and teratogenic effects and lethal dose (LD50) of maropitant in ovo, using fertile chicken eggs. The study was designed in two stages, CHEST-I and CHEST-II. For CHEST-I, 210 fertile eggs were divided into seven equal groups; control, saline solution and 5 different doses of maropitant (10, 5, 2.5, 1.25, 0.625 mg/kg) injected groups. For CHEST-II, 150 fertile eggs were divided into five equal groups; control, saline solution and 3 different doses of maropitant (8, 6, 4 mg/kg)-injected groups. Eggs were opened on day 21 of incubation. Maropitant did not cause teratogenicity at any dose, while higher embryonic death rates were observed at doses above 4 mg/kg. The LD50 dose of maropitant was determined as 7.24 mg/kg. In conclusion, maropitant should only be used after full consideration of risks and benefits in pregnancy.

Comparing Clinical Outcomes of Tiotropium/Olodaterol, Umeclidinium/Vilanterol, and Indacaterol/Glycopyrronium Fixed-Dose Combination Therapy in Patients with Chronic Obstructive Pulmonary Disease in Taiwan: A Multicenter Cohort Study

Background

Long-acting beta-agonists (LABA) and long-acting muscarinic antagonists (LAMA) combination therapy improved lung function and health-related quality-of-life and reduced exacerbation rates and dyspnea in symptomatic chronic obstructive pulmonary disease (COPD) patients. We compared the real-world effects of three fixed-dose LABA/LAMA combinations for COPD in Taiwan.

Methods

This multicenter, retrospective study evaluated 1-year outcomes after LABA/LAMA combination therapy in patients with symptomatic COPD. Exacerbations and symptoms of COPD, lung functions, and therapy escalation were compared among patients using tiotropium/olodaterol, umeclidinium/vilanterol and indacaterol/glycopyrronium. Propensity score matching (PSM) was applied to balance the baseline characteristics.

Results

Data of 1,617 patients were collected. After PSM, time to first moderate-to-severe COPD exacerbation was comparable among three groups, while the annualized rates of the exacerbation (episodes/patient/year) in patients receiving tiotropium/olodaterol (0.19) or umeclidinium/vilanterol (0.17) were significantly lower than those receiving indacaterol/glycopyrronium (0.38). COPD-related symptoms were stable over the treatment period, and there was no significant difference in the changes of symptom scores including CAT and mMRC among three groups at the end of the study period.

Conclusion

This study presented valuable real-world outcome in terms of exacerbation and treatment response of COPD patients treated with fixed-dose LABA/LAMA regimens in Taiwan. The annualized rates of moderate-to-severe exacerbation in patients receiving tiotropium/olodaterol or umeclidinium/vilanterol were significantly lower than those receiving indacaterol/glycopyrronium, though the time to first moderate-to-severe exacerbation was similar among different fixed-dose LABA/LAMA combinations.

Penehyclidine hydrochloride suppresses inflammation response and reduces podocyte injury in diabetic nephropathy by targeting fibrinogen-like protein 2

BACKGROUND

Diabetic nephropathy (DN) is one of the main complications of diabetes. Penehyclidine hydrochloride (PHC) has anti-inflammatory, anti-apoptotic and anti-oxidative stress effects. Nevertheless, whether PHC can be used to prevent podocyte injury has not been reported.

OBJECTIVES

This present study aimed to identify the functional role of PHC in DN as well as its underlying mechanism.

METHODS

The high-glucose (HG)-induced podocyte damage in vitro model was established. The proliferation, apoptotic rate, inflammatory factors, and gene/protein expressions of HG-induced MPC5 cells were determined using CCK-8 assay, flow cytometry, ELISA, real-time PCR, and Western blot upon PHC treatment. Co-immunoprecipitation experiments and pull-down assay were performed to verify the interactions between fibrinogen-like protein 2 (Fgl2) and toll-like receptor 4 (TLR4) as well as TLR4 and NLRP3. A rat in vivo model was used to confirm the effect of PHC treatment.

RESULTS

PHC treatment reduced Fgl2 expression and inhibited HG-induced podocyte injury and DN-induced kidney damage. Flg2 was associated with TLR4 and NLRP3. It was further proved that PHC treatment suppressed the TLR4-NF-кB and NLRP3-Caspase-1 pathways through Fgl2, which eventually inhibited inflammatory cytokines and prevented HG-induced podocyte injury both in vitro and in vivo.

CONCLUSION

PHC treatment possibly ameliorates DN by preventing podocyte injury via inactivating the TLR4-NF-кB and NLRP3-Caspase-1 signaling pathways by Flg2.

APR-246—The Mutant TP53 Reactivator—Increases the Effectiveness of Berberine and Modified Berberines to Inhibit the Proliferation of Pancreatic Cancer Cells

Pancreatic ductal adenocarcinoma (PDAC) is the most common form of pancreatic cancer. In ~75% of PDAC, the tumor suppressor TP53 gene is mutated. Novel approaches to treat cancer involve compounds called mutant TP53 reactivators. They interact with mutant TP53 proteins and restore some of their growth suppressive properties, but they may also interact with other proteins, e.g., TP63 and TP73. We examined the ability of the TP53 reactivator APR-246 to interact with eleven modified berberine compounds (NAX compounds) in the presence and absence of WT-TP53 in two PDAC cell lines: the MIA-PaCa-2, which has gain of function (GOF) TP53 mutations on both alleles, and PANC-28, which lacks expression of the WT TP53 protein. Our results indicate the TP53 reactivator-induced increase in therapeutic potential of many modified berberines.

Expression of the α7 Nicotinic Acetylcholine Receptor Is Critically Required for the Antifibrotic Effect of PHA-543613 on Skin Fibrosis

INTRODUCTION

Targeting the α7 nicotinic acetylcholine receptor (α7nAChR) has recently been suggested as a potential new treatment for fibrotic skin diseases. Here, we performed a genetic and pharmacologic approach to clarify the role of this receptor in the bleomycin (BLM) mouse model of skin fibrosis using α7nAChR KO mice.

METHODS

We analyzed the expression of extracellular matrix (ECM) components in murine skin using quantitative RT-PCR, pepsin digestion/SDS-PAGE of proteins and performed hydroxyproline assays as well as histological/immunohistochemical staining of skin sections. To identity the target cells of the α7nAChR agonist PHA-543613, we used murine dermal fibroblasts (MDF). We tested their response to the profibrotic cytokine transforming growth factor-β1 (TGF-β1) and utilized gene silencing to elucidate the role of the α7nAChR.

RESULTS

We confirmed our previous findings on C3H/HeJ mice and detected a suppressive effect of PHA-543613 on BLM-induced skin fibrosis in the mouse strain C57BL/6J. This antifibrotic effect of PHA-543613 was abrogated in α7nAChR-KO mice. Interestingly, α7nAChR-KO animals exhibited a basal profibrotic signature by higher RNA expression of ECM genes and hydroxyproline content than WT mice. In WT MDF, PHA-543613 suppressed ECM gene expression induced by TGF-β1. Gene silencing of α7nAChR by small interfering RNA neutralized the effects of PHA-543613 on TGF-β1-mediated ECM gene expression.

CONCLUSION

In summary, we have identified the α7nAChR as the essential mediator of the antifibrotic effect of PHA-543613. MDF are directly targeted by PHA-543613 to suppress collagen synthesis. Our findings emphasize therapeutic exploitation of α7nAChR receptor agonists in fibrotic skin diseases.

Effectiveness of orally administered maropitant and ondansetron in preventing preoperative emesis and nausea in healthy dogs premedicated with a combination of hydromorphone, acepromazine, and glycopyrrolate

OBJECTIVE

To compare effectiveness of maropitant and ondansetron in preventing preoperative vomiting and nausea in healthy dogs premedicated with a combination of hydromorphone, acepromazine, and glycopyrrolate.

ANIMALS

88 dogs owned by rescue organizations.

PROCEDURES

Dogs received maropitant (n = 29) or ondansetron (28) PO 2 hours prior to premedication or did not receive an antiemetic (31; control). Dogs were evaluated for vomiting, nausea, and severity of nausea (scored for 6 signs) for 15 minutes following premedication with hydromorphone, acepromazine, and glycopyrrolate.

RESULTS

A significantly lower percentage of dogs vomited after receiving maropitant (3/29 [10%]), compared with control dogs (19/31 [62%]) and dogs that received ondansetron (15/28 [54%]). A significantly lower percentage of dogs appeared nauseated after receiving maropitant (3/29 [10%]), compared with control dogs (27/31 [87%]) and dogs that received ondansetron (14/28 [50%]), and a significantly lower percentage of dogs appeared nauseated after receiving ondansetron, compared with control dogs. Nausea severity scores for hypersalivation, lip licking, hard swallowing, and hunched posture were significantly lower for dogs that received maropitant than for control dogs, and scores for hypersalivation, lip licking, and hard swallowing were significantly lower for dogs that received ondansetron than for control dogs.

CONCLUSIONS AND CLINICAL RELEVANCE

Oral administration of maropitant 2 hours prior to premedication with hydromorphone reduced the incidence of vomiting and the incidence and severity of nausea in healthy dogs. Oral administration of ondansetron reduced the incidence and severity of nausea but not the incidence of vomiting.

Retrospective evaluation of maropitant and perioperative factors affecting postoperative appetite in cats

The primary goal of this retrospective study was to evaluate the effect of postoperative appetite return in cats premedicated with maropitant citrate. Medical records of 75 cats admitted for gastrointestinal (GI) and urogenital (UG) surgeries were reviewed and analyzed. Buprenorphine analgesia was used with 36 cats (48%) premedicated with maropitant and 39 cats (52%) that were used as a control group. No significant differences in postoperative appetite return were reported with maropitant premedication compared to controls. Age, breed, preoperative weight, surgery type, surgery and anesthesia times, and total hospitalization time were also evaluated and were not reported to be significantly associated with postoperative appetite return. Presenting complaints of hyporexia or anorexia were significantly associated with earlier postoperative appetite return. Results of this study suggest that cats treated with buprenorphine for GI or UG surgeries do not have postoperative appetites return sooner when premedicated with maropitant.

Efficacy and safety of once-daily, single-inhaler fluticasone furoate/umeclidinium/vilanterol versus fluticasone furoate/vilanterol in Japanese patients with inadequately controlled asthma: the CAPTAIN study

OBJECTIVE

In CAPTAIN, a double-blind, parallel-group, Phase IIIA study, fluticasone furoate/umeclidinium/vilanterol (FF/UMEC/VI) improved lung function, symptoms and asthma control versus FF/VI in patients with inadequately controlled asthma. Here, we report efficacy and safety from a Japanese cohort in CAPTAIN.

METHODS

Adults with inadequately controlled asthma despite inhaled corticosteroid/long-acting β₂-agonist (ICS/LABA) were randomized (1:1:1:1:1:1) to once-daily FF/VI (100/25 mcg or 200/25 mcg) or FF/UMEC/VI (100/31.25/25 mcg, 100/62.5/25 mcg, 200/31.25/25 mcg, or 200/62.5/25 mcg) for ≥24 weeks. Endpoints included change from baseline in clinic trough FEV₁ (primary), annualized rate of moderate/severe asthma exacerbations (key secondary), clinic FEV₁ 3 h post-dose, and Asthma Control Questionnaire (ACQ)-7, St George's Respiratory Questionnaire (SGRQ) (all Week 24), Evaluating Respiratory Symptoms (E-RS): Asthma total scores (Weeks 21-24) (all secondary). Adverse events and adverse events of special interest were monitored. Clinical trials.gov registry no: NCT02924688.

RESULTS

Overall, 229 of 2436 patients in the intention-to-treat (ITT) population were from Japan. In this cohort, change from baseline in trough FEV₁ for FF/UMEC/VI 100/62.5/25 mcg versus FF/VI 100/25 mcg was 105 mL (95% confidence interval -5, 216) and 69 mL (-42, 179) for 200/62.5/25 mcg versus 200/25 mcg. These observations were supported by clinic FEV₁ at 3 h post-dose. Moderate/severe exacerbation incidence was low and similar across pooled treatment groups (FF/VI, FF/UMEC 31.25 mcg/VI, FF/UMEC 62.5 mcg/VI). All pooled groups demonstrated clinically important improvements from baseline in ACQ-7, SGRQ and E-RS: Asthma total scores. Safety profiles were consistent with the overall ITT population, with no new safety concerns.

CONCLUSION

FF/UMEC/VI is an effective option with a favorable risk-benefit profile in Japanese patients with uncontrolled moderate or severe asthma on ICS/LABA.

Converting the 3-quinuclidinone reductase from Agrobacterium tumefaciens into the ethyl 4-chloroacetoacetate reductase by site-directed mutagenesis

In this study, the 3-quinuclidinone reductase from Agrobacterium tumefaciens (AtQR) was modified by site-directed mutagenesis. And we further obtained a saturation mutant library in which the residue 197 was mutated. A single-point mutation converted the wild enzyme that originally had no catalytic activity in reduction of ethyl 4-chloroacetoacetate (COBE) into an enzyme with catalytic activity. The results of enzyme activity assays showed that the seven variants could asymmetrically reduce COBE to ethyl (S)-4-chloro-3-hydroxybutyrate ((S)-CHBE) with NADH as coenzyme. In the library, the variant E197N showed higher catalytic efficiency than others. The E197N was optimally active at pH 6.0 and 40°C, and the catalytic efficiency (k_cat /K_m ) for COBE was 51.36 s^-1 ·mM^-1 . This study showed that the substrate specificity of AtQR could be changed through site-directed mutagenesis at the residue 197.

A thiol-bound drug reservoir enhances APR-246-induced mutant p53 tumor cell death

The tumor suppressor gene TP53 is the most frequently mutated gene in cancer. The compound APR-246 (PRIMA-1Met/Eprenetapopt) is converted to methylene quinuclidinone (MQ) that targets mutant p53 protein and perturbs cellular antioxidant balance. APR-246 is currently tested in a phase III clinical trial in myelodysplastic syndrome (MDS). By in vitro, ex vivo, and in vivo models, we show that combined treatment with APR-246 and inhibitors of efflux pump MRP1/ABCC1 results in synergistic tumor cell death, which is more pronounced in TP53 mutant cells. This is associated with altered cellular thiol status and increased intracellular glutathione-conjugated MQ (GS-MQ). Due to the reversibility of MQ conjugation, GS-MQ forms an intracellular drug reservoir that increases availability of MQ for targeting mutant p53. Our study shows that redox homeostasis is a critical determinant of the response to mutant p53-targeted cancer therapy.

Synergic effect of a quinuclidine benzamide complexed with borane, the LMA10233, in combination with seven pesticides

Some quinuclidine benzamide compounds have been found to modulate nicotinic acetylcholine receptors in both mammals and insects. In particular, the quaternarization of 3-amino quinuclidine benzamide derivatives with dichloromethane gave charged N-chloromethylated quinuclidine compounds, disclosing an antagonist profile on homomeric α7 nAChRs. Here, we synthesized and studied the toxicological effect of LMA10233, a quinuclidine-borane complex analogue, the LMA10233, on the pea aphid Acyrthosiphon pisum and found that LMA10233 only exhibit proper toxicity on A. pisum larvae when applied in concentrations of over 10 μg/ml. We assessed the ability of LMA10233 to enhance the toxicity of different insecticides. When a sublethal concentration of LMA10233 was combined with the LC₁₀ of each compound, we found a strong increase in toxicity at 24 h and 48 h of exposure for clothianidin, fipronil and chlorpyrifos, and only at 24 h for imidacloprid, acetamiprid and deltamethrin. However, when the pesticide was used at the LC₅₀, only acetamiprid showed a synergistic effect with LMA10233. When the concentration of LMA10233 was decreased, we found that up to 80-90% of mortality was obtained due to the synergism between acetamiprid and LMA10233. No similar effect was observed with other insecticides. We conclude that such quinuclidine-borane complex compounds could increase the toxic effect of insecticides at low concentrations.

Evaluation of the effectiveness of preoperative administration of maropitant citrate and metoclopramide hydrochloride in preventing postoperative clinical gastroesophageal reflux in dogs

OBJECTIVE

To investigate the prophylactic effectiveness of preoperative administration of maropitant citrate and metoclopramide hydrochloride in preventing postoperative clinical gastroesophageal reflux (GER) in dogs and to identify risk factors for clinical postoperative GER in dogs.

ANIMALS

93 client-owned dogs undergoing surgery at the Washington State University Veterinary Teaching Hospital between March 2016 and February 2017.

PROCEDURES

Dogs were randomly assigned to either the intervention group (preoperatively received maropitant and metoclopramide) or the control group (did not preoperatively receive maropitant and metoclopramide). After surgery, all dogs were recovered and monitored, and occurrences of GER were noted. The prophylactic effectiveness of maropitant and metoclopramide was evaluated, and univariate and multivariate logistic regression analyses were performed to identify variables associated with postoperative clinical GER in dogs.

RESULTS

No meaningful difference in the incidence of clinical GER during the postoperative period was detected between the control and intervention groups. Results indicated that variables associated with significantly increased odds of postoperative clinical GER included the male sex (OR, 9.2; 95% confidence interval [CI], 1.26 to 195.0), an overweight BCS (OR, 12.3; 95% CI, 2.1 to 135.1), gastrointestinal surgery (OR, 30.5; 95% CI, 3.0 to 786.9), and requirement for a dexmedetomidine constant rate infusion after surgery (OR, 9.6; 95% CI, 1.3 to 212.5).

CONCLUSIONS AND CLINICAL RELEVANCE

Findings indicated that incidence of clinical GER during the postoperative period was not lower for dogs that received preoperative prophylactic administration of metoclopramide and maropitant, compared with incidence dogs that did not receive the prophylactic treatment. Further research is required into alternative measures to prevent postoperative clinical GER in dogs.

[Multi-Center Joint Study on the Survey of Antiemetic Therapy for the Prevention of Nausea and Vomiting in Combination Therapy with a Mild Emetic Antineoplastic Drug]

While many studies have demonstrated the prevention of nausea and vomiting in patients receiving moderately or highly emetogenic anti-cancer agents, there are few reports of mildly emetogenic anti-cancer agents. In the present study, we performed a 2-year multi-center study to determine the types and efficacy of antiemetic therapy administered in a total of 77 cancer patients who received mildly emetogenic anti-cancer agents between September 2015 and August 2017. The effectiveness of antiemetic therapy was evaluated based on the frequency of nausea and vomiting and use of rescue medication. This information was reported by patients and collected every 24 hours for 120 hours after the administration of anti-cancer agents with a mild emetogenic risk. The combination of 5-HT3 receptor antagonist(1 or 3 mg granisetron, 0.75 mg palonosetron) and 6.6 mg dexamethasone was the most common antiemetic therapy used in our patient population. There was no significant difference in the effectiveness of all 5-HT3 receptor antagonists that were evaluated. Gemcitabine and nab-paclitaxel were the most commonly used with a total of 64 patients receiving a combination of these mildly emetogenic agents. Poor performance status was associated with failure to achieve total control(TC)of nausea and vomiting(p=0.0304), while habitual alcohol consumption was associated with TC of nausea and vomiting(p=0.0331).

The effect of solifenacin on postvoid dribbling in women: results of a randomized, double-blind placebo-controlled trial

INTRODUCTION AND HYPOTHESIS

To determine the effectiveness of the muscarinic receptor antagonist solifenacin (VESIcare®) in the treatment of postvoid dribbling (PVD).

METHODS

We carried out a multicenter, 12-week, double-blind, randomized, placebo-controlled, parallel design study. Between 2012 and 2015, a total of 118 women (age 18-89 years) with PVD at least twice/weekly, were randomized to receive solifenacin (5 mg; n = 58) or placebo (n = 60) once daily. The primary outcome was the percentage reduction in PVD episodes. Secondary outcomes included the percentage of patients with ≥50% reduction in PVD episodes and changes in quality of life.

RESULTS

There were no differences in either the primary or secondary outcome variables. Subgroup analysis, based on those with more severe disease (>10 PVD episodes/week), showed a greater and significant percentage reduction in the frequency of PVD episodes per day (60.3% vs 32.1%; p = 0.035) and a higher percentage of patients showing ≥50% reduction in the frequency of PVD episodes with solifenacin (68.1% vs 45.8%; p = 0.0476). A significant solifenacin effect occurred at week 2 and continued through week 12 for the subgroup. For solifenacin, PVD reduction was the same for the entire cohort and subgroup, whereas for placebo, it was 10% lower in the subgroup, declining from 42% to 32%.

CONCLUSION

There were no differences in PVD outcomes between the solifenacin and placebo groups. Solifenacin may play a role in treating women with the most severe symptoms. Because of the powerful placebo response seen in this study, behavior-based interventions may be useful for treating PVD.

[Comparisons of therapeutic efficacy and safety of solifenacin versus tolterodine in patients with overactive bladder: a meta-analysis of outcomes]

OBJECTIVE

To compare the clinical efficacy and safety of solifenacin versus tolterodine in patients with overactive bladder (OAB).

METHODS

Literature searches were performed with PubMed, EMBASE, Ovid and Google Scholar databases, Wanfang and CNKI from inception to October 2013 for comparative studies assessing solifenacin and tolterodine for OAB. The data were extracted and evaluated by two reviewers independently according to the Cochrane Handbook for Systematic Reviews. Meta-analyses were conducted with RevMan 5.2.

RESULTS

A total of 7 studies involving 1 805 patients were retrieved. Compared with tolterodine immediate release (IR), the number of urgency episodes and urge incontinence episodes in 24 h and the rate of dry mouth were significantly lower in patients on solifenacin (RR = -0.34, 95% CI: -0.50--0.18, P = 0.00; RR = -0.29, 95% CI:-0.55--0.04, P = 0.03; RR = 0.58, 95% CI: 0.41-0.83, P = 0.00) and the rate of constipation was higher in those on solifenacin (RR = 2.72, 95% CI: 1.38-5.39, P = 0.00). No significant differences existed between tolterodine IR and solifenacin in mean micturition volume per voiding and micturitions episodes in 24 h (P = 0.05,0.08). Between solifenacin and tolterodine extended release (ER), the number of urgency episodes, micturition and urge incontinence episodes in 24 h and mean micturition volume per voiding were not statistically different (all P > 0.05). The incidence of major adverse events, such as dry mouth, constipation and blurred vision, was not significantly different (all P > 0.05). And most adverse events were mild.

CONCLUSIONS

Solifenacin is superior to tolterodine IR in treating OAB symptoms. However the rate of constipation is higher for solifenacin. Both solifenacin and tolterodine ER have similar therapeutic efficacies and adverse events.

[Clinical observation of penehyclidine hydrochloride as the preanesthetic medication before operation for patients with cleft lip/palate]

OBJECTIVE

To compare the effects of penehyclidine hydrochloride, atropine and scopolamine as the preanesthetic medication before operation for patient with cleft lip/palate (CL/P) who would undergo general anesthesia.

METHODS

120 CL/P patients who would undergo general anesthesia with tracheal intubation as research objects were chosen. The patients were divided into three groups randomly, group of penehyclidine hydrochloride (group PH), group of atropine (group ATR) and group of scopolamine (group SCO), 40 patients in each group. Penehyclidine hydrochloride (0.01 mg/kg), atropine (0.01 mg/kg) or scopolamine (0.006 mg/kg) was given respectively to the patients. The changes of heart rate, temperature, blood pressure and the secretion of respiratory tract were observed before medication, 15 minutes and 30 minutes after medication, after trachea cannula and after operation.

RESULTS

There were no significant changes in heart rate, temperature and blood pressure in group PH after medication (P > 0.05). The heart rate and temperature in group ATR and group SCO increased significantly after medication (P < 0.05), however, the blood pressure had no obvious change (P > 0.05). The secretion of respiratory tract was decreased significantly in group PH comparing to group ATR and group SCO when the operation was over (P < 0.05).

CONCLUSION

Penehyclidine hydrochloride has no significant effect on heart rate, temperature and blood pressure to the patients, and it's effect of secretion inhibition is longer and it is better than atropine and scopolamine.

Absence of NK1 receptors in human blood lymphocytes and granulocytes

Substance P is a peptide that exerts its activity through the interaction with specific receptors that are distributed in different brain areas. Given the potential of NK1 receptor antagonists as antidepressants, the availability of a peripheral model of NK1 receptors would be particularly relevant for the possibility to perform studies in samples of patients. Therefore, with the present study we aimed to explore the possible existence of NK1 receptors by means of [3H]SR140333 and [125I]BHSP that behave as, respectively, antagonist and agonist, at this level, in human blood lymphocytes and granulocytes of healthy donors. The results of the present study failed to detect the presence of a high-affinity and saturable binding of [3H]SR140333 and [125I]BHSP in human blood cells, whereas a specific binding for both compounds was found in rat cerebral cortex that was used as the control tissue. These findings would question the presence of NK1 receptors in human circulating cells.

Effect of sabcomeline on muscarinic and dopamine receptor binding in intact mouse brain

Sabcomeline [(R-(Z)-(+)-alpha-(methoxyiamino)-1-azabicyclo[2.2.2]octane-3-acetonitrile)] is a potent and functionally selective muscarinic M1 receptor partial agonist. However, little is known of the binding properties of sabcomeline under in vivo conditions. In this study, muscarinic receptor occupancy by sabcomeline in mouse brain regions and heart was estimated using [3H]quinuclidinyl benzilate (QNB) and [3H]N-methylpiperidyl benzilate (NMPB) as radioligands. In the cerebral cortex, hippocampus, and striatum, the estimated IC50 value of sabcomeline for [3H]NMPB binding was almost 0.2 mg/kg. Sabcomeline was not a selective ligand to M1 receptors as compared with biperiden in vivo. In the cerebral cortex, maximum receptor occupancy was observed about 1 hr after intravenous injection of sabcomeline (0.3 mg/kg), and the binding availability of mACh receptors had almost returned to the control level by 3-4 hr. These findings indicated that the binding kinetics of sabcomeline is rather rapid in mouse brain. Examination of dopamine D2 receptor binding revealed that sabcomeline affected the kinetics of both [3H]raclopride and [3H]N-methylspiperone (NMSP) binding in the striatum. It significantly decreased the k3 and k4 of [3H]raclopride binding resulting in an increase in binding potential (BP = k3/k4 = Bmax/Kd) in sabcomeline-treated mice, and an approximately 15% decrease in k3 of [3H]NMSP binding was also observed. Although the mechanism is still unclear, sabcomeline altered dopamine D2 receptor affinity or availability by modulations via neural networks.

Iodine-123 labelled Z-(R,R)-IQNP: a potential radioligand for visualization of M(1 )and M(2) muscarinic acetylcholine receptors in Alzheimer's disease

Z-(R)-1-Azabicyclo[2.2.2]oct-3-yl (R)-alpha-hydroxy-alpha-(1-iodo-1-propen-3-yl)-alpha-phenylacetate (Z-IQNP) has high affinity to the M(1 )and M(2) muscarinic acetylcholine receptor (mAChR) subtypes according to previous in vitro and in vivo studies in rats. In the present study iodine-123 labelled Z-IQNP was prepared for in vivo single-photon emission tomography (SPET) studies in cynomolgus monkeys. SPET studies with Z-[(123)I]IQNP demonstrated high accumulation in monkey brain (>5% of injected dose at 70 min p.i.) and marked accumulation in brain regions such as the thalamus, the neocortex, the striatum and the cerebellum. Pretreatment with the non-selective mAChR antagonist scopolamine (0.2 mg/kg) inhibited Z-[(123)I]IQNP binding in all these regions. The percentage of unchanged Z-[(123)I]IQNP measured in plasma was less than 10% at 10 min after injection, which may be due to rapid hydrolysis, as has been demonstrated previously with the E-isomer of IQNP. Z-[(123)I]IQNP showed higher uptake in M(2)-rich regions, compared with previously obtained results with E-[(123)I]IQNP. In conclusion, the radioactivity distribution from Z-[(123)I]IQNP in monkey brain indicates that Z-[(123)I]IQNP binds to the M(1)- and M(2)-rich areas and provides a high signal for specific binding, and is thus a potential ligand for mAChR imaging with SPET.

Identification of muscarinic receptor subtypes present in cerebellar granule cells: prevention of [3H]propylbenzilyl choline mustard binding with specific antagonists

Subtypes of muscarinic receptors (possible m1 to m5) can be identified by their molecular size, specific effector systems and antagonist specificity. In membranes prepared from primary cultures of cerebellar granule cells, [3H]propylbenzilylcholine mustard [( 3H]PBCM) irreversibly binds to muscarinic receptive proteins, having two major molecular sizes, 92 and 66 kDa. With relatively short periods of incubation (approx. 30 min, 30 degrees C) of [3H]PBCM with atropine, a nonspecific competitive receptor antagonist, the irreversible labeling of these muscarinic proteins by [3H]PBCM could be prevented. Methoctramine, a specific competitive antagonist at muscarinic receptors coupled to inhibition of adenylate cyclase, protected most of the muscarinic receptors having a molecular size of 66 kDa from binding of [3H]PBCM. These 66 kDa receptive proteins are suggested to be muscarinic m2 and m4 subtypes. (-)Quinuclidinyl xanthene-9-carboxylate [(-)QNX], a somewhat specific competitive antagonist at muscarinic receptors coupled to hydrolysis of phosphatidylinositol, prevented the binding of [3H]PBCM to 92 kDa muscarinic receptive proteins and some 66 kDa muscarinic receptive proteins. The 92 kDa receptive proteins are suggested to be the muscarinic m3 subtype and the 66 kDa proteins could be either the m2 or m4 receptor subtype. Lastly, pirenzepine, a nonspecific antagonist at muscarinic receptors mediating inhibition of adenylate cyclase and hydrolysis of PI in these cultures, resembled (-)QNX in preventing binding of [3H]PBCM to the 92 kDa receptive proteins and some 66 kDa receptive proteins. The suggested subtypes of muscarinic receptors, specifically bound by pirenzepine should be the m3 (92 kDa) and the m4 (66 kDa) subtypes, since pirenzepine reportedly exhibits a low affinity for the muscarinic m2 subtype.(ABSTRACT TRUNCATED AT 250 WORDS)

A quantitative structure-activity relationship study for local anesthetic activity of mono-and diaryl-2-quinuclidinylcarbinols

The local anesthetic activity of a series of arylquinuclidinylcarbinols is shown to be significantly correlated with their lipophilic character, suggesting that lipophilicity is an important factor for the local anesthetic action of drugs.

Effect of dopaminergic drugs on enhancement of the binding of quinuclidinyl benzilate by phencyclidine in vivo

Phencyclidine has been shown to enhance the specific binding of [3H]quinuclidinyl benzilate (QNB) in the brain of the mouse when both compounds are given in vivo. Since a variety of studies indicate that dopaminergic (DA) systems are involved in the action of phencyclidine, it seemed that DA systems might mediate the enhancement of the binding of QNB by phencyclidine. The results of the present studies demonstrate that the neurotoxin 6-hydroxydopamine, the DA D1 antagonist (R)-8-[chloro]-2,3,4,5-tetrahydro-3-methyl-5-phenyl-1-H-3-benzazepine-7- ol) (SCH23390), the DA D1 agonist p-dibenzylamino benzonitrile (SKF38393) and the DA D2 antagonist spiperone, all failed to modify the ability of phencyclidine to enhance the accumulation of QNB in brain. Quinpirole, a DA D2 agonist diminished accumulation of QNB after phencyclidine, however, this effect was confounded by quinpirole decreasing the non-specific binding of QNB, as well as increasing concentrations of QNB in plasma, when given with phencyclidine. In contrast, haloperidol, a DA antagonist, decreased the enhanced specific binding of QNB after phencyclidine without any apparent confounding influences. Since haloperidol is also known to strongly inhibit the binding of ligands to the sigma receptors, it was hypothesized that the actions of phencyclidine and haloperidol on the binding of QNB in vivo may be through sigma receptors rather than DA systems.

Structure-binding relationship of quinuclidinyl benzilate analogs on N4TG1 neuroblastoma muscarinic receptors

By Scatchard plot analysis of [3H]QNB (quinuclidinyl benzilate) binding, there are 2 x 10(5) muscarinic sites/cell with a KD about 10 nM in N4TG1 neuroblastoma cells. We have now examined a group of compounds structurally related to aprophen and QNB for their ability to compete with the binding of QNB to the muscarini receptor. Using this structure-inhibition relationship, the functional groups of the muscarinic ligand necessary for binding were partially characterized. It was found that the quinuclidinyl ring structure of QNB can be substituted by either alkane, H, or pyrrolidine at the N without loosing their ability to bind. The addition to the quinuclidinyl ring increases the bulk of the structure and decreases binding. Like the benzilate in QNB, a similar hydrophobic structure is apparently required for the binding.

Muscarinic acetylcholine receptors in Alzheimer's disease. In vivo imaging with iodine 123-labeled 3-quinuclidinyl-4-iodobenzilate and emission tomography

In vivo imaging of muscarinic acetylcholine receptor binding function in a patient with Alzheimer's disease, using single-photon emission computed tomography and iodine 123-labeled 3-quinuclidinyl-4-iodobenzilate (123I-QNB), and perfusion imaging using 123I-N-isopropyl p-iodoamphetamine are described. A profound decrease in perfusion to the posterior temporal and parietal cortex and a more uniform uptake of 123I-QNB throughout the cerebral cortex were observed. The 123I-QNB activity ratio was reduced compared with that of a normal age-matched subject, suggesting a moderate impairment in muscarinic receptor binding function in Alzheimer's disease. Furthermore, and more importantly, our study demonstrates that images of in vivo receptor binding can be obtained easily and nontraumatically using 123I-QNB and single-photon emission computed tomography.

The affinity of [3H]quinuclidinyl benzilate and some other radioligands for glass microfiber and cellulose filters in some common liquid scintillation solvents

The optimum conditions for measuring radioactivity in the filtration assay of muscarinic cholinoceptors with tritiated quinuclidinyl benzilate are to use Whatman GF/B filters and to add a simple toluene scintillant to them while they are still damp. Practically all the radioactive material is then slowly extracted into the scintillant and high counting efficiencies are obtained after 24 h. Dried filters, or dry filters in control experiments in the absence of receptor, adsorb much of the radioactivity with a 30% reduction in counting efficiency. Other scintillants were able to extract the radioactive material from dry filters, but were generally not preferable to toluene. The GF/B filters performed better than other glass microfiber and cellulose filters in terms of retention of receptor-bound ligand, rapid filtration rates, and low filter blanks. Toluene is unsuitable as a scintillant with GF/B filters for some other radioligands examined.

Muscarinic antagonist binding site heterogeneity as evidenced by autoradiography after direct labeling with [3H]-QNB and [3H]-pirenzepine

Saturable, high affinity binding of tritiated pirenzepine [( 3H]-PZ) was obtained in slide mounted tissue sections prior to performing autoradiographic localization of these binding sites. The binding in tissue sections of rostral rat forebrain gave a KD of 18nM and a Bmax of 51 fmoles/mg tissue. These binding characteristics are similar to those previously obtained in homogenate membrane preparations and indicate the binding is taking place in a similar manner. The distribution of the binding sites labeled with [3H]-PZ represented a subpopulation of those which could be labeled with tritiated quinuclidinyl benzilate [( 3H]-QNB). Thus, [3H]-PZ and [3H]-QNB both label regions of the cerebral cortex, hippocampus, striatum and dorsal horn of the spinal cord, while sites in the cerebellum, nucleus tractus solitarius, facial nucleus and ventral horn of the spinal cord are labeled with [3H]-QNB and not by [3H]-PZ. These observations indicate separate regions of the brain where antagonists bind to subtypes of muscarinic receptors.

Muscarinic receptors in lung and trachea: autoradiographic localization using [3H]quinuclidinyl benzilate

[3H]Quinuclidinyl benzilate binding to slide-mounted frozen sections of ferret lung was of high affinity (KD 63 +/- 14 pM, mean +/- S.E., n = 4), and characteristic of interaction with muscarinic cholinergic receptors. Light microscopic autoradiography showed muscarinic receptors to be localized predominantly to smooth muscle of trachea and intrapulmonary cartilaginous airways, and to submucosal glands. There was much less labelling of bronchiolar smooth muscle, airway epithelium and vascular smooth muscle and no labelling of alveoli. This distribution of receptors parallels that of cholinergic innervation.

Analogues of 3-quinuclidinyl benzilate

A number of analogues of 3-quinuclidinyl benzilate (QNB) have been synthesized and their affinities to muscarinic receptor from rat or dog ventricular muscle measured. We have determined that the muscarinic receptor can to a different degree accommodate either a halogen in the ortho, meta, or para position of one phenyl ring or the replacement of one phenyl ring with an alkyl group. Our in vitro competition studies show that the affinities lie within a 270-fold range, from the highest affinity compound, 3-quinuclidinyl alpha-hydroxy-alpha-cyclopentylphenylacetate (2), to the lowest affinity compound, 3-quinuclidinyl alpha-hydroxy-alpha-2-propargylphenylacetate (11).

Muscarinic cholinergic receptor binding: in vivo depiction using single photon emission computed tomography and radioiodinated quinuclidinyl benzilate

An attempt was made to characterize, in vivo, specific binding to the muscarinic cholinergic receptor in the calf using the radioiodinated ligand quinuclidinyl benzilate (123I-OH-QNB) and single photon detection emission computed tomography (SPECT). The supratentorial brain activity was significantly increased after the intravenous infusion of 123I-OH-QNB as compared to free 123I. Scopolamine, a muscarinic cholinergic receptor antagonist, decreased the measured brain activity when infused prior to 123I-OH-QNB consistent with pharmacologic blockade of specific receptor binding. Quantitative in vitro tissue distribution studies obtained following SPECT imaging were consistent with regionally distinct specific receptor binding in the striatum and cortical gray matter, nonspecific binding in the cerebellum, and pharmacologic blockade of specific binding sites with scopolamine. Although 123I-OH-QNB is not the ideal radioligand, our limited success will hopefully encourage the development of improved binding probes for SPECT imaging and quantitation.

Muscarinic cholinergic receptor sites in cerebral blood vessels

Muscarinic cholinergic receptor sites in cerebral blood vessels were analyzed directly by using radioligand binding techniques with the specific muscarinic antagonist [3H]quinuclidinyl benzilate (QNB) as ligand. Specific binding of [3H]QNB to membrane preparations from isolated bovine pia-arachnoid vessels was found to be saturable, of high affinity (Kd = 5.4 X 10(-10) M) and selectively inhibited by muscarinic antagonists (atropine) and agonists (acetylcholine, carbachol and methacholine). Scatchard and Hill plot analyses of the data indicated one class of sites for the antagonists, but two independent classes of sites were revealed with the agonists. Interestingly, the high and low affinities of the agonist sites correlated with the concentrations of agonist which have been reported to produce dilation and contraction, respectively, of isolated pial artery segments. A substantial number of specific [3H]QNB binding sites also were measured in isolated bovine cerebral microvessels providing direct evidence for muscarinic receptors in intracerebral vessels. In contrast, specific [3H]QNB binding was barely detectable in mesenteric blood vessels. Choline acetyltransferase (ChAT) activity was measured in parallel with [3H]QNB binding. The relative distribution of choline acetyltransferase was correlated with that for the binding, with the highest values observed in the intracerebral microvessels. This suggests a functional innervation of the cerebrovascular muscarinic receptors.

Affinity labeling of muscarinic receptors in rat cerebral cortex with a photolabile antagonist

Highly potent photoaffinity probes for muscarinic binding sites were prepared by the incorporation of an azido group into the benzilic acid moiety in two compound, 3-quinuclidinyl benzilate (3QNB) and N-methyl-4-piperidyl benzilate (4NMPB). Inactivation of muscarinic sites in rat cortex depends on the formation of a reversible complex with the azides prior to their photolytic conversion to the highly reactive nitrenes. During photolysis, radiolabeled azido-4NMPB interacted specifically and with high affinity (Kd = 1.06 nM) with the muscarinic receptors, and the ligand could be covalently incorporated into a macromolecule of about 86,000 Mr, presumably the muscarinic receptor. The incorporation was almost stoichiometric when compared to determination of receptor density by reversible ligands. Atropine (10 microM) afforded specific protection (greater than 83%) of the receptor against inactivation by azido-[3H]4NMPB. This compound and the other ligands described here (i.e., amino-4NMPB, amino-3QNB, and azido-3QNB) represent powerful potential probes for the biochemical isolation and characterization of muscarinic receptors.

The interaction of mequitazine with phospholipid model membranes

The effect of increasing concentrations of mequitazine, a quinuclidinylmethyl-phenothiazine, on the phase transition temperature (Tc), the broadening of the transition peak, the enthalpy and entropy of transition of dimyristoyl-, dipalmitoyl- and distearoylphosphatidylcholine (DPPC) liposomes was studied. Pest critical micelle concentrations of mequitazine (CMC = 5.23 X 10(-2) M), caused broadening of the transition peak and lowering of the Tc of pure liposomes. The ratio of peak heights from the nuclear magnetic resonance (NMR) spectra of egg phosphatidycholine liposomes was used as a criterion for assessing the interaction of the drug with phsopholipid membranes. Mequitazine interacts with both the polar head groups and hydrophobic membrane interior.

3-Quinuclidinyl benzilate hydrolysis in dilute aqueous solution

The hydrolysis kinetics of 3-quinuclidinyl benzilate were determined over the pH 0-14 range at different temperatures in solutions buffered to a constant pH. Analysis of data extrapolated to zero buffer concentrations permitted construction of an overall rate expression for pH 0-14 and 0-100 degrees. Reaction mechanisms are discussed.