Effects of the microbial community on the formation of volatile compounds and biogenic amines during the traditional brewing of Hongqu rice wine.

As a typical representative of Chinese rice wine (Huangjiu), Hongqu rice wine is famous for its red color, mellow taste and strong fragrance. However, due to the open brewing environment and traditional fermentation technology, there are some safety risks in traditional brewed Hongqu rice wine, such as a certain amount of biogenic amines. In this study, the dynamic changes and the differences of microbial communities and volatile flavor components between two types of Hongqu rice wine with high and low biogenic amine contents (LBAW and HBAW) during the traditional brewing were systematically investigated. The results showed that the total biogenic amine contents in LBAW and HBAW were 20.91 and 69.06 mg/L, respectively. The contents of putrescine, cadaverine, spermine and spermidine in HBAW were significantly higher than those in LBAW, and it was noteworthy that spermine content in HBAW was 17.62 mg/L, which was not detected in LBAW. In addition, the volatile flavor characteristics of the two kinds of Hongqu rice wine were obviously different. The contents of acetophenone, n-butyl butanoate and benzothiazole were obviously higher in HBAW, while the contents of isoamyl acetate, ethyl lactate, ethyl caprate and phenylethyl alcohol were significantly higher in LBAW. High-throughput sequencing of 16S/ITS amplicon revealed that Weissella, Kosakonia, Pantoea, Monascus, Saccharomyces and Millerozyma were the predominant microbial genera during the traditional brewing of HBAW, while Weissella, Kosakonia, Monascus, Saccharomyces and Issatchenkia were the predominant microbial genera during the traditional brewing of LBAW. Correlation analysis revealed that biogenic amines were significantly negatively correlated with unclassified_o_Saccharomycetales, Cyberlindnera, Zygoascus, Aspergillus and Acinetobacter, but positively correlated with Lactobacillus, Pediococcus, Millerozyma and Apiotrichum. In addition, we also found that Lactobacillus, Pediococcus and Saccharomyces were significantly positively correlated with most of the volatile flavor components, while Candida, Trichosporon and Monascus were significantly negatively correlated with most of the volatile flavor components. In addition, bioinformatical analysis based on PICRUSt demonstrated that the key enzymes for biogenic amine biosynthesis were more abundant in the microbial community of HBAW than LBAW. These findings demonstrate that the formations of volatile flavor and biogenic amines in Hongqu rice wine are influenced by microbial community during the fermentation. This work facilitates scientific understanding of the formation mechanism of biogenic amines, and may be useful to develop effective strategies to improve the quality of Hongqu rice wine.

Anti-inflammatory Mechanism Involved in 4-Ethylguaiacol-Mediated Inhibition of LPS-Induced Inflammation in THP-1 Cells.

4-Ethylguaiacol, a common aroma compound of baijiu (a traditional Chinese alcoholic beverage), was assessed for its potential anti-inflammatory effects in an LPS-induced THP-1 cell model. To characterize the effect of 4-ethylguaiacol on the LPS-induced inflammatory response, the mRNA and protein expression of the TLR4-MAPKs-NF-κB-IκBα-AP-1, Nrf2-HO-1, and AMPK-SIRT1 pathways were monitored by ELISA, real-time PCR, and Western blotting. On the basis of the result, 4-ethylguaiacol exerted anti-inflammatory effects at doses of 10, 100, and 500 µM (the concentration of 4-ethylguaiacol in gujinggong baijiu is in the range of 1044 ± 44 to 1661 ± 63 µg/L) and significantly mitigated LPS-induced inflammation via activation of the Nrf2-HO-1 and AMPK-SIRT1 pathways and inhibition of NF-κB and AP-1 activation, thereby markedly inhibiting the activation of inflammasomes and down-regulating the production of inflammatory cytokines. These results indicated that 4-ethylguaiacol could reverse LPS-induced inflammatory responses and is a natural, potent anti-inflammatory component in baijiu.

Differences in airway remodeling and airway inflammation among moderate-severe asthma clinical phenotypes.

BACKGROUND: To identify asthma clinical phenotypes using cluster analysis and improve our understanding of heterogeneity in asthma. METHODS: Clustering approaches were applied to 203 patients who were diagnosed with asthma in XinHua Hospital (January 2012 to December 2015). One hundred and twenty patients underwent multi-slice spiral computed tomography (MSCT) examination and 30 underwent bronchial mucosal biopsy for evaluation of airway remodeling and airway inflammation among the phenotypes. RESULTS: Four groups were identified. Patients in cluster 1 (n=52) had early onset atopic asthma and patients in cluster 2 (n=65) had small airway obstruction and atopic asthma. Cluster 3 (n=52) was a unique group of patients with late-onset and non-atopic asthma. Patients in cluster 4 (n=34) had severe airflow obstruction and obvious airway remodeling as observed on MSCT (P<0.05). According to the immunohistochemistry of IL-5 and IL-17 (P<0.05), the results of clusters 1 and 2 may be attributable to the Th2 immune response, whereas those of clusters 3 and 4 to the Th17 immune response. CONCLUSIONS: Four distinct clinical phenotypes of asthma were identified by cluster analysis. The results of the MSCT and pathological examinations may suggest specific pathogeneses among the phenotypes.

Propofol attenuates intermittent hypoxia induced up-regulation of proinflammatory cytokines in microglia through inhibiting the activation of NF-Bκ/p38 MAPK signalling.

As immune sentinels of the central nervous system (CNS), microglia is pivotal cellular mediator of neuroinflammatory processes. Activation of microglia might elicit the expression of proinflammatory cytokines involved in the progression of neuroinflammatory diseases. Numerous studies have demonstrated that propofol (2,6-diisopropylphenol) has an effective anti-inflammatory property. Intermittent hypoxia (IH), as a result of obstructive sleep apnoea (OSA), could lead to neuron damage and neuroinflammation in the CNS. Here, we determined the effects of propofol on the inflammatory response in microglia during IH. The levels of nuclear factor-Bκ (NF-κB) inhibitor (IκB) and activated p38 mitogen-activated protein kinase (MAPK) exposed to IH with or without propofol treatment were detected by Western blot. The viability of cells exposed to various concentrations of propofol was monitored with MTT assay. The production and mRNA levels of tumor necrosis factor- α(TNF-α) and interleukin-6 (IL-6) were evaluated by qRT-PCR and ELISA, respectively. As results, IH exposure obviously promoted the activation of NF-κB/p38 MAPK signalling and the secretion of TNF-α and IL-6. Propofol was not toxic to microglia. Compared with the control group, propofol attenuated the IH-induced activation of NF-Bκ and p38 MAPK, which accompanied with reduction of proinflammatory cytokine secretion. These data suggested that propofol down-regulated the IH-induced secretion of proinflammatory cytokine, and inhibit inflammatory responses in microglia, and might be involved in attenuation of the p38 MAPK and NF-κB signalling pathways. Overall, propofol could contribute to alleviating IH-induced CNS diseases in patients by inhibiting p38 MAPK and NF-κB mediated inflammation in microglia..

SENP1 inhibits the IH-induced apoptosis and nitric oxide production in BV2 microglial cells.

To reveal SUMOylation and the roles of Sentrin-specific proteases (SENP)s in microglial cells under Intermittent hypoxia (IH) condition would provide more intensive view of understanding the mechanisms of IH-induced central nervous system (CNS) damage. Hence, in the present study, we detected the expression levels of SENPs in microglial cells under IH and normoxia conditions via RT-PCR assay. We found that SENP1 was significantly down-regulated in cells exposure to IH. Subsequently, the effect of IH for the activation of microglia and the potential roles of SENP1 in the SENP1-overexpressing cell lines were investigated via Western blotting, RT-PCR and Griess assay. The present study demonstrated the apoptosis-inducing and activating role of IH on microglia. In addition, we revealed that the effect of IH on BV-2 including apoptosis, nitric oxide synthase (iNOS) expression and nitric oxide (NO) induction can be attenuated by SENP1 overexpression. The results of the present study are of both theoretical and therapeutic significance to explore the potential roles of SENP1 under IH condition and elucidated the mechanisms underlying microglial survival and activation.