The prevalence of asthma has increased in recent years, and is characterized by airway hyperresponsiveness and inflammation. Many patients report using alternative therapies to self-treat asthma symptoms as adjuncts to short-acting and long-acting b-agonists and inhaled corticosteroids (ICS). As many as 40% of patients with asthma use herbal therapies to manage asthma symptoms, often without proven efficacy or known mechanisms of action. Therefore, investigations of both the therapeutic and possible detrimental effects of isolated components of herbal treatments on the airway are important. We hypothesized that ginger and its active components induce bronchodilation by modulating intracellular calcium ([Ca 21 ] i ) in airway smooth muscle (ASM). In isolated human ASM, ginger caused significant and rapid relaxation. Four purified constituents of ginger were subsequently tested for ASM relaxant properties in both guinea pig and human tracheas: ] i regulation. These purified compounds may provide a therapeutic option alone or in combination with accepted therapeutics, including b 2 -agonists, in airway diseases such as asthma.

b-Agonists are the first-line therapy to alleviate asthma symptoms by acutely relaxing the airway. Purified components of ginger relax airway smooth muscle (ASM), but the mechanisms are unclear. By elucidating these mechanisms, we can explore the use of phytotherapeutics in combination with traditional asthma therapies. The objectives of this study were to: (1) determine if 6-gingerol, 8-gingerol, or 6-shogaol potentiate b-agonist-induced ASM relaxation; and (2) define the mechanism(s) of action responsible for this potentiation. Human ASM was contracted in organ baths. Tissues were relaxed dose dependently with b-agonist, isoproterenol, in the presence of vehicle, 6-gingerol, 8-gingerol, or 6-shogaol (100 mM). Primary human ASM cells were used for cellular experiments. Purified phosphodiesterase (PDE) 4D or phospholipase C b enzyme was used to assess inhibitory activity of ginger components using fluorescent assays. A G-LISA assay was used to determine the effects of ginger constituents on Ras homolog gene family member A activation. Significant potentiation of isoproterenol-induced relaxation was observed with each of the ginger constituents. 6-Shogaol showed the largest shift in isoproterenol half-maximal effective concentration. 6-Gingerol, 8-gingerol, or 6-shogaol significantly inhibited PDE4D, whereas 8-gingerol and 6-shogaol also inhibited phospholipase C b activity. 6-Shogaol alone inhibited Ras homolog gene family member A activation. In human ASM cells, these constituents decreased phosphorylation of 17-kD protein kinase C-potentiated inhibitory protein of type 1 protein phosphatase and 8-gingerol decreased myosin light chain phosphorylation. Isolated components of ginger potentiate b-agonist-induced relaxation in human ASM. This potentiation involves PDE4D inhibition and cytoskeletal regulatory proteins. Together with b-agonists, 6-gingerol, 8-gingerol, or 6-shogaol may augment existing asthma therapy, resulting in relief of symptoms through complementary intracellular pathways.Keywords: asthma; adrenergic receptor; myosin light chain; lung; bronchodilation Clinical RelevanceNatural herbal remedies, including ginger, have long been used to treat respiratory conditions. Many individuals with asthma use herbal therapies to self-treat their asthma symptoms; however, little is known regarding how these compounds work in the airway. In the current work, we show that 6-gingerol, 8-gingerol, and 6-shogaol potentiate b-agonist-induced relaxation of airway smooth muscle by inhibiting both phosphodiesterase 4D and phosphatidylinositol-specific phospholipase C, leading to downstream regulation of contractile proteins. These data suggest that natural compounds can work in combination with traditional asthma therapies to relieve asthma symptoms.

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Background: New heart failure therapies that safely augment cardiac contractility and output are needed. Previous apelin peptide studies have highlighted the potential for APJ (apelin receptor) agonism to enhance cardiac function in heart failure. However, apelin’s short half-life limits its therapeutic utility. Here, we describe the preclinical characterization of a novel, orally bioavailable APJ agonist, BMS-986224. Methods: BMS-986224 pharmacology was compared with (Pyr 1 ) apelin-13 using radio ligand binding and signaling pathway assays downstream of APJ (cAMP, phosphorylated ERK [extracellular signal-regulated kinase], bioluminescence resonance energy transfer–based G-protein assays, β-arrestin recruitment, and receptor internalization). Acute effects on cardiac function were studied in anesthetized instrumented rats. Chronic effects of BMS-986224 were assessed echocardiographically in the RHR (renal hypertensive rat) model of cardiac hypertrophy and decreased cardiac output. Results: BMS-986224 was a potent (Kd=0.3 nmol/L) and selective APJ agonist, exhibiting similar receptor binding and signaling profile to (Pyr 1 ) apelin-13. G-protein signaling assays in human embryonic kidney 293 cells and human cardiomyocytes confirmed this and demonstrated a lack of signaling bias relative to (Pyr 1 ) apelin-13. In anesthetized instrumented rats, short-term BMS-986224 infusion increased cardiac output (10%–15%) without affecting heart rate, which was similar to (Pyr 1 ) apelin-13 but differentiated from dobutamine. Subcutaneous and oral BMS-986224 administration in the RHR model increased stroke volume and cardiac output to levels seen in healthy animals but without preventing cardiac hypertrophy and fibrosis, effects differentiated from enalapril. Conclusions: We identify a novel, potent, and orally bioavailable nonpeptidic APJ agonist that closely recapitulates the signaling properties of (Pyr 1 ) apelin-13. We show that oral APJ agonist administration induces a sustained increase in cardiac output in the cardiac disease setting and exhibits a differentiated profile from the renin-angiotensin system inhibitor enalapril, supporting further clinical evaluation of BMS-986224 in heart failure.

Purpose: To determine if ixabepilone is a substrate for cytochrome P450 3A4 (CYP3A4) and if its metabolism by this cytochrome is clinically important, we did a clinical drug interaction study in humans using ketoconazole as an inhibitor of CYP3A4. Experimental Design: Human microsomes were used to determine the cytochrome P450 enzyme(s) involved in the metabolism of ixabepilone. Computational docking (CYP3A4) studies were done for epothilone B and ixabepilone. A follow-up clinical study was done in patients with cancer to determine if 400 mg/d ketoconazole (inhibitor of CYP3A4) altered the pharmacokinetics, drug-target interactions, and pharmacodynamics of ixabepilone. Results: Molecular modeling and human microsomal studies predicted ixabepilone to be a good substrate for CYP3A4. In patients, ketoconazole coadministration resulted in a maximum ixabepilone dose administration to 25 mg/m 2 when compared with single-agent therapy of 40 mg/m 2 . Coadministration of ketoconazole with ixabepilone resulted in a 79% increase in AUC 0-1 . The relationship of microtubule bundle formation in peripheral blood mononuclear cells to plasma ixabepilone concentration was well described by the Hill equation. Microtubule bundle formation in peripheral blood mononuclear cells correlated with neutropenia. Conclusions: Ixabepilone is a good CYP3A4 substrate in vitro ; however, in humans, it is likely to be cleared by multiple mechanisms. Furthermore, our results provide evidence that there is a direct relationship between ixabepilone pharmacokinetics, neutrophil counts, and microtubule bundle formation in PBMCs. Strong inhibitors of CYP3A4 should be used cautiously in the context of ixabepilone dosing.