circRNA expression patterns and circRNA-miRNA-mRNA networks during CV-A16 infection of SH-SY5Y cells.

Coxsackievirus A16 (CV-A16) has caused worldwide epidemics of hand, foot, and mouth disease (HFMD) in infants and preschool children. Circular RNAs (circRNAs), a class of noncoding RNA molecules, participate in the progression of viral infectious diseases. Although the function of circRNAs has been a heavily researched topic, their role in CV-A16 infection is still unclear. In this study, the viral effects of CV-A16 on the cellular circRNA transcriptome were investigated using next-generation sequencing technology. The results showed that a total of 8726, 8611, and 6826 circRNAs were identified at 0, 12, and 24 h postinfection, respectively. Moreover, it was found that 1769 and 1192 circRNAs were differentially expressed in at 12 and 24 h postinfection, respectively. The common differentially expressed circRNAs were used for functional annotation analysis, and it was found that the parent genes of differentially expressed circRNAs might be associated with the viral infection process, especially the "Immune system process" in GO analysis and the "Inflammation mediated by chemokine and cytokine signaling pathway" in KEGG analysis. Subsequently, circRNA-miRNA-mRNA regulatory networks were constructed, and the hsa_circ_0004447/hsa-miR-942-5p/MMP2, hsa_circ_0078617/hsa-miR-6780b-5p/MMP2 and hsa_circ_0078617/hsa-miR-5196-5p/MMP2 regulatory axes were identified by enrichment analysis as important networks during the progression of CV-A16 infection. Finally, six dysregulated circRNAs were selected for validation and were verified to be consistent with the sequencing results. Considering all of these results, to the best of our knowledge, this study is the first to present a comprehensive overview of circRNAs induced by CV-A16 infection, and this research demonstrated that a network of enriched circRNAs and circRNA-associated competitive endogenous RNAs (ceRNAs) is involved in the regulation of CV-A16 infection, thereby helping to elucidate the mechanisms underlying CV-A16-host interactions.

NLRP3-dependent pyroptosis exacerbates coxsackievirus A16 and coxsackievirus A10-induced inflammatory response and viral replication in SH-SY5Y cells.

Coxsackievirus A16 (CV-A16) and coxsackievirus A10 (CV-A10), more commonly etiological agents of hand, foot and mouth disease (HFMD), are capable of causing severe neurological syndromes with high fatalities, but their neuropathogenesis has rarely been studied. Mounting evidence indicated that pyroptosis is an inflammatory form of cell death that might be widely involved in the pathogenic mechanisms of neurotropic viruses. Our study was designed to examine the effects of NLRP3-mediated pyroptosis in CV-A16- and CV-A10-induced inflammatory neuropathologic formation. In this work, it was showed that SH-SY5Y cells were susceptible to CV-A16 and CV-A10, and meanwhile their infections could result in a decreasing cell viability and an increasing LDH release as well as Caspase1 activation. Moreover, CV-A16 and CV-A10 infections triggered NLRP3-mediated pyroptosis and promoted the release of inflammatory cytokines. Additionally, activated NLRP3 accelerated the pyroptosis formation and aggravated the inflammatory response, but inhibited NLRP3 had a dampening effect on the above situation. Finally, it was further revealed that NLRP3 agonist enhanced the viral replication, but NLRP3 inhibitor suppressed the viral replication, suggesting that NLRP3-driven pyroptosis might support CV-A16 and CV-A10 production in SH-SY5Y cells. Together, our findings demonstrated a mechanism by which CV-A16 and CV-A10 induce inflammatory responses by evoking NLRP3 inflammasome-regulated pyroptosis, which in turn further stimulated the viral replication, providing novel insights into the pathogenesis of CV-A16 and CV-A10 infections.

Characterization of the key odorants contributing to retronasal olfaction during bread consumption.

Gas chromatography-ion mobility spectrometry (GC-IMS) and dynamic quantitative descriptive analysis (D-QDA) were combined to explore the aroma release and perception from the retronasal cavity during bread consumption. D-QDA results elucidated that the sweet, creamy, and roasty notes were the most active attributes during oral processing. The final stage of oral processing had the most complicated changing pattern, followed by the intermediate and initial stages. Thirteen aroma compounds were detected in the retronasal cavity, of which eight had odor activity values (OAVs) greater than 1. The total OAV changing pattern was consistent with the D-QDA results. Addition experiments further confirmed that acetoin, 2,3-butanedione, and 3-(methylthio)propanal were key aroma compounds contributing to retronasal olfaction. 2,3-Butanedione and 3-(methylthio)propanal were both identified as key odorants in the mouth cavity and retronasal cavity during oral processing, but they had 30% loss during the breath delivery from the mouth cavity to the retronasal cavity.

Characterization of the aroma release and perception of white bread during oral processing by gas chromatography-ion mobility spectrometry and temporal dominance of sensations analysis.

The purpose of this study was to investigate the aroma release and perception from white bread during oral processing by gas chromatography-ion mobility spectrometry (GC-IMS) and dynamic sensory evaluation of temporal dominance of sensations (TDS). TDS curves indicated that two maximum aroma perception signals, fermentation-like and flour-like attributes, were perceived at the beginning and swallowing, respectively. The fermentation-like, flour-like, and sour attributes were the 3 dominant aromas during oral processing. A total of 35 volatile compounds were detected in the mouth cavity during chewing white bread, 19 of them were confirmed and quantified by using the respective external standard. Based on PLSR analysis, 8 aroma compounds were predicted as potent odorants contributing to the aroma perception from chewing white bread. By application of odor activity values analysis and addition experiments, ethyl butanoate, butyl acetate, hexanal, 3-(methylthio)-propanal, 3-methylbutanal, and 2,3-butanedione were confirmed as the key odorants contributing to the aroma perception during chewing of white bread.

Characterization of the oral breakdown, sensory properties, and volatile release during mastication of white bread.

The oral breakdown, sensory properties, and volatile release during mastication of white bread were investigated. The results of correlation analysis for white bread's physical properties and it's oral physiological parameters during chewing have elucidated that bread's physical properties determined the oral processing behavior. During chewing of white bread, 15 dominant ions with regularly changing patterns were monitored by proton transfer reaction-mass spectrometry (PTR-MS). These dominant ions derived from 32 volatile compounds were further confirmed by pure standards. Partial least squares regression (PLSR) analysis was used to explore the positive correlations between the sensory analysis and the dominant aroma compounds. Results have shown that 9 aroma compounds were predicted as the potent odorants contributing to the changes in aroma profiles. Finally, 3-hydroxy-2-butanone, 2-methyl-1-propanol, and heptanoic acid were confirmed as the key aroma compounds contributing to the changes in aroma profiles of white bread before and after chewing.