[Pharmacological profiles of F-1322, a novel anti-asthmatic agent. (1). Mechanisms of action]

Classification models and SAR analysis on thromboxane A2 synthase inhibitors by machine learning methods

Thromboxane A2 synthase (TXS) is a promising drug target for cardiovascular diseases and cancer. In this work, we conducted a structure-activity relationship (SAR) study on 526 TXS inhibitors for bioactivity prediction. Three types of descriptors (MACCS fingerprints, ECFP4 fingerprints, and MOE descriptors) were utilized to characterize inhibitors, 24 classification models were developed by support vector machine (SVM), random forest (RF), extreme gradient boosting (XGBoost), and deep neural networks (DNN). Then we reduced the number of fingerprints according to the contribution of descriptors to the models, and constructed 16 extra models on simplified fingerprints. In general, Model_4D built by DNN algorithm and 67 bits MACCS fingerprints performs best. The prediction accuracy of the model on the test set is 0.969, and Matthews correlation coefficient (MCC) is 0.936. The distance between compound and model (dSTD-PRO) was used to characterize the application domain of the model. In the test set of Model_4D, dSTD-PRO of 91.5% compounds is lower than the corresponding training set threshold (threshold0.90 = 0.1055), and the accuracy of these compounds is 0.983. In addition, the important descriptors were summarized and further analyzed. It showed that aromatic nitrogenous heterocyclic groups were beneficial to improve the bioactivity of TXS inhibitors.

Suppressive effects of F-1322 on the antigen-induced late asthmatic response and pulmonary eosinophilia in guinea pigs

We investigated the effects of F-1322 (N-[2-[4-(benzhydryloxy)piperidino]ethyl]-3-hydroxy-5-(3-pyridylmethoxy)-2-naphthamide), a new compound that inhibits both thromboxane A2 synthetase and 5-lipoxygenase and that functions as a histamine antagonist, on the Ascaris antigen-induced late asthmatic response and pulmonary eosinophilia in guinea pigs. Oral administration of F-1322 (10-100 mg/kg) inhibited the antigen-induced late asthmatic response in a dose-dependent manner. Histological analysis revealed that F-1322 prevented the accumulation of eosinophils in the airways and this was paralleled by a decrease in the number of eosinophils and lymphocytes recovered in bronchoalveolar lavage fluid. F-1322 (0.1-10 microM) inhibited eotaxin-induced chemotaxis and actin polymerization of eosinophils in vitro in a concentration-dependent manner, while oral administration of F-1322 dose-dependently suppressed the migration of eosinophils into the airways in vivo in response to infusion of interleukin 5 and eotaxin in combination. F-1322 may, thus, improve the late asthmatic response in this model, in part, by preventing the accumulation of eosinophils in the airways. The pharmacological profile of F-1322 indicates that this drug is likely to be useful in the treatment of allergic diseases such as asthma.

Inhibitory effect of F-1322 on allergic eosinophil infiltration in airways

The effects of F-1322 (N-[2-[4-(benzhydryloxy)piperidino]ethyl]-3-hydroxy-5-(3-pyridy lmethoxy)-2-naphthamide) on antigen-induced eosinophil infiltration and interleukin-5 production in the airways and on in vitro eosinophil migration were investigated. F-1322 (10-30 mg/kg, p.o.) inhibited antigen-induced eosinophil infiltration and interleukin-5 production in the airways of sensitized mice in a dose-dependent manner. Furthermore, F-1322 (0.1-10 microM) prevented the in vitro migration of eosinophils from guinea-pigs and humans induced by recombinant human interleukin-5, platelet-activating factor, and leukotriene B4 in a concentration-dependent manner. These results indicate that F-1322 has an inhibitory effect on allergic eosinophil infiltration of the airways by preventing both eosinophil migration and interleukin-5 production. These pharmacological profiles suggest that F-1322 will be a useful therapeutic for allergic diseases, especially asthma.