著者
Yuto Amano Hiroshi Honda Ryusuke Sawada Yuko Nukada Masayuki Yamane Naohiro Ikeda Osamu Morita Yoshihiro Yamanishi
出版者
The Japanese Society of Toxicology
雑誌
The Journal of Toxicological Sciences (ISSN:03881350)
巻号頁・発行日
vol.45, no.3, pp.137-149, 2020 (Released:2020-03-06)
参考文献数
47
被引用文献数
5

In silico models for predicting chemical-induced side effects have become increasingly important for the development of pharmaceuticals and functional food products. However, existing predictive models have difficulty in estimating the mechanisms of side effects in terms of molecular targets or they do not cover the wide range of pharmacological targets. In the present study, we constructed novel in silico models to predict chemical-induced side effects and estimate the underlying mechanisms with high general versatility by integrating the comprehensive prediction of potential chemical-protein interactions (CPIs) with machine learning. First, the potential CPIs were comprehensively estimated by chemometrics based on the known CPI data (1,179,848 interactions involving 3,905 proteins and 824,143 chemicals). Second, the predictive models for 61 side effects in the cardiovascular system (CVS), gastrointestinal system (GIS), and central nervous system (CNS) were constructed by sparsity-induced classifiers based on the known and potential CPI data. The cross validation experiments showed that the proposed CPI-based models had a higher or comparable performance than the traditional chemical structure-based models. Moreover, our enrichment analysis indicated that the highly weighted proteins derived from predictive models could be involved in the corresponding functions of the side effects. For example, in CVS, the carcinogenesis-related pathways (e.g., prostate cancer, PI3K-Akt signal pathway), which were recently reported to be involved in cardiovascular side effects, were enriched. Therefore, our predictive models are biologically valid and would be useful for predicting side effects and novel potential underlying mechanisms of chemical-induced side effects.
著者
Masaaki Miyazawa Yuichi Ito Nanae Kosaka Yuko Nukada Hitoshi Sakaguchi Hiroyuki Suzuki Naohiro Nishiyama
出版者
The Japanese Society of Toxicology
雑誌
The Journal of Toxicological Sciences (ISSN:03881350)
巻号頁・発行日
vol.33, no.1, pp.71-83, 2008 (Released:2008-02-26)
参考文献数
37
被引用文献数
19 24 18

Dendritic cells (DCs), including Langerhans cells (LCs), play a critical role in the induction phase of allergic contact hypersensitivity. Following exposure to chemical allergens in the skin, LCs undergo a maturation process leading to the up-regulation of expression of co-stimulatory molecules, such as CD86, CD54 and CD40. Our previous study revealed that chemical allergens induce phenotype alterations (e.g., CD86, CD54 and CD40) and cytokine production (TNF-α and IL-8) in THP-1 cells that possibly reflect the maturation of dendritic cells during skin sensitization. However, the physiological signals for phenotypic alterations by chemical allergens are still not fully understood. Therefore, in this study, we investigated the effect of TNF-α and extracellular ATP on THP-1 cell activation induced by chemical allergens. Kinetic studies revealed that TNF-α and IL-8 release occurred in a time-dependent manner with release of two cytokines beginning at 3 hr post-exposure to well-known haptens, DNCB and NiSO4. While recombinant human TNF-α augmented CD54 and CD40 expression in a dose-dependent manner, rhTNF-α did not increase CD86 expression. Furthermore, neutralization of TNF-α activity strongly inhibited CD54 and CD40 expression induced by allergens. On the contrary, extracellular ATP induced the up-regulation of both CD86 and CD54 expression. In the presence of the P2 receptor antagonist suramin, the up-regulation of CD86 and CD54 expression by allergens was in part suppressed. Therefore, we postulate that not only TNF-α but also extracellular ATP may contribute to cell activation following allergen stimulation, which might reflect the mechanism by which DCs respond to allergens.