Browsing by Subject "Quinolines"

Now showing 1 - 5 of 5
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    Foretinib mitigates cutaneous nerve fiber loss in experimental diabetic neuropathy
    (Springer Nature, 2022-05-19) Daeschler, Simeon C.; Zhang, Jennifer; Gordon, Tessa; Borschel, Gregory H.; Feinberg, Konstantin; Surgery, School of Medicine
    Diabetes is by far, the most common cause of neuropathy, inducing neurodegeneration of terminal sensory nerve fibers associated with loss of sensation, paresthesia, and persistent pain. Foretinib prevents die-back degeneration in cultured sensory and sympathetic neurons by rescuing mitochondrial activity and has been proven safe in prospective clinical trials. Here we aimed at investigating a potential neuroprotective effect of Foretinib in experimental diabetic neuropathy. A mouse model of streptozotocin induced diabetes was used that expresses yellow fluorescent protein (YFP) in peripheral nerve fibers under the thy-1 promoter. Streptozotocin-injected mice developed a stable diabetic state (blood glucose > 270 mg/dl), with a significant reduction of intraepidermal nerve fiber density by 25% at 5 weeks compared to the non-diabetic controls. When diabetic mice were treated with Foretinib, a significantly greater volume of the cutaneous nerve fibers (67.3%) in the plantar skin was preserved compared to vehicle treated (37.8%) and non-treated (44.9%) diabetic mice while proximal nerve fiber morphology was not affected. Our results indicate a neuroprotective effect of Foretinib on cutaneous nerve fibers in experimental diabetic neuropathy. As Foretinib treated mice showed greater weight loss compared to vehicle treated controls, future studies may define more sustainable treatment regimen and thereby may allow patients to take advantage of this neuroprotective drug in chronic neurodegenerative diseases like diabetic neuropathy.
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    Impact of the expanded label for elexacaftor/tezacaftor/ivacaftor in people with cystic fibrosis with no F508del variant in the USA
    (European Respiratory Society, 2024-11-14) Cromwell, Elizabeth A.; Ostrenga, Josh S.; Sanders, Don B.; Morgan, Wayne; Castellani, Carlo; Szczesniak, Rhonda; Burgel, Pierre-Regis; Pediatrics, School of Medicine
    Background: Elexacaftor/tezacaftor/ivacaftor (ETI), which is approved for people with cystic fibrosis (pwCF) with a F508del variant, was further approved based on in vitro data in the USA for those carrying at least one of 177 rare CFTR (cystic fibrosis transmembrane conductance regulator) variants. Methods: PwCF, aged ≥6 years, carrying no F508del variant but with at least one of these 177 rare variants, were identified within the US Cystic Fibrosis Foundation Patient Registry (CFFPR) between 2020 and 2022. The evolution of forced expiratory volume in 1 s (FEV1) percentage predicted and rates of pulmonary exacerbations were analysed over the first year following ETI initiation, using a linear regression with generalised estimating equations and a negative binomial model, respectively. Results: A total of 1791 individuals aged ≥6 years with rare CFTR variants were eligible for ETI, corresponding to 5.2% of CFFPR participants. 815 individuals (45.5%), of which 57.9% were already treated with another CFTR modulator, initiated ETI within the first 2 years following approval. Individuals with more severe respiratory disease were more likely to initiate ETI, whereas those previously treated with another CFTR modulator or those with no private insurance coverage had less ETI initiation. ETI initiation was associated with an increase in mean FEV1 % pred by +3.39 (95% CI 2.14-4.64) and a decrease in the rates of pulmonary exacerbations (adjusted rate ratio 0.55, 95% CI 0.38-0.79). These effects were greater in individuals naïve of previous CFTR modulators. Conclusions: Extension of the ETI label to rare CFTR variants is associated with meaningful improvements in lung function and a marked reduction in pulmonary exacerbations.
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    In Vitro Metabolism of Montelukast by Cytochrome P450s and UDP-Glucuronosyltransferases
    (ASPET, 2015-12) Cardoso, Josiane de Oliveira; Oliveira, Regina Vincenzi; Lu, Jessica Bo Li; Desta, Zeruesenay; Department of Medicine, IU School of Medicine
    Montelukast has been recommended as a selective in vitro and in vivo probe of cytochrome P450 (P450) CYP2C8 activity, but its selectivity toward this enzyme remains unclear. We performed detailed characterization of montelukast metabolism in vitro using human liver microsomes (HLMs), expressed P450s, and uridine 5′-diphospho-glucuronosyltransferases (UGTs). Kinetic and inhibition experiments performed at therapeutically relevant concentrations reveal that CYP2C8 and CYP2C9 are the principal enzymes responsible for montelukast 36-hydroxylation to 1,2-diol. CYP3A4 was the main catalyst of montelukast sulfoxidation and stereoselective 21-hydroxylation, and multiple P450s participated in montelukast 25-hydroxylation. We confirmed direct glucuronidation of montelukast to an acyl-glucuronide. We also identified a novel peak that appears consistent with an ether-glucuronide. Kinetic analysis in HLMs and experiments in expressed UGTs indicate that both metabolites were exclusively formed by UGT1A3. Comparison of in vitro intrinsic clearance in HLMs suggest that direct glucuronidation may play a greater role in the overall metabolism of montelukast than does P450-mediated oxidation, but the in vivo contribution of UGT1A3 needs further testing. In conclusion, our in vitro findings provide new insight toward montelukast metabolism. The utility of montelukast as a probe of CYP2C8 activity may be compromised owing to involvement of multiple P450s and UGT1A3 in its metabolism.
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    Management of hypertension in advanced kidney disease
    (Wolters Kluwer, 2022) Georgianos, Panagiotis I.; Agarwal, Rajiv; Medicine, School of Medicine
    Purpose of review: The aim of this study was to present recent developments in pharmacotherapy of hypertension in patients with advanced chronic kidney disease (CKD). Recent findings: In the AMBER trial, compared with placebo, the potassium-binder patiromer mitigated the risk of hyperkalaemia and enabled more patients with uncontrolled resistant hypertension and stage 3b/4 CKD to tolerate and continue spironolactone treatment; add-on therapy with spironolactone provoked a clinically meaningful reduction of 11-12 mmHg in unattended automated office SBP over 12 weeks of follow-up. In the BLOCK-CKD trial, the investigational nonsteroidal mineralocorticoid-receptor-antagonist (MRA) KBP-5074 lowered office SBP by 7-10 mmHg relative to placebo at 84 days with a minimal risk of hyperkalaemia in patients with advanced CKD and uncontrolled hypertension. The CLICK trial showed that the thiazide-like diuretic chlorthalidone provoked a placebo-subtracted reduction of 10.5 mmHg in 24-h ambulatory SBP at 12 weeks in patients with stage 4 CKD and poorly controlled hypertension. Summary: Enablement of more persistent spironolactone use with newer potassium-binding agents, the clinical development of novel nonsteroidal MRAs with a more favourable benefit-risk profile and the recently proven blood pressure lowering action of chlorthalidone are three therapeutic opportunities for more effective management of hypertension in high-risk patients with advanced CKD.
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    Quinoline Derivative MC1626, a Putative GCN5 Histone Acetyltransferase (HAT) Inhibitor, Exhibits HAT-Independent Activity against Toxoplasma gondii
    (American Society for Microbiology, 2007) Smith, Aaron T.; Livingston, Meredith R.; Mai, Antonello; Filetici, Patrizia; Queener, Sherry F.; Sullivan, William J., Jr.; Pharmacology and Toxicology, School of Medicine
    We report that quinoline derivative MC1626, first described as an inhibitor of the histone acetyltransferase (HAT) GCN5, is active against the protozoan parasite Toxoplasma gondii in vitro. However, MC1626 does not inhibit Toxoplasma GCN5 HATs or reduce HAT-mediated activity; rather, this quinoline may target the plastid organelle called the apicoplast.