Mahuang Xixin Fuzi decoction ameliorates apoptosis via the mitochondrial-mediated signaling pathway in MCM cells.

ETHNOPHARMACOLOGICAL RELEVANCE: Mahuang Xixin Fuzi Decoction (MXF), as a classical prescription of traditional Chinese medicine (TCM), has been used to treat the symptoms of fever, nasal congestion and headache in elderly people for almost a thousand years. AIM OF THE STUDY: The purpose of this study was to evaluate the effects and possible mechanisms of MXF on thermal stimulation-induced mouse cardiac myocytes (MCM) cell apoptosis. MATERIALS AND METHODS: The apoptosis of the MCM cell model was induced by a PCR-calculated temperature control system with a gradual heating pattern at 43 °C for 1 h. The cytotoxic effects were determined using real-time cell analyzer (RTCA) technology. Annexin V-FITC/7-AAD staining, and JC-1 fluorescence were used to assess apoptosis. Specific substrates, enzyme-linked immunosorbent assays (ELISAs), and Western blotting were used to identify proteins in the mitochondrial-mediated pathway. The identification of chemical components in the mouse heart was performed by ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry analysis. RESULTS: MXF inhibited apoptosis through the mitochondrial-mediated signaling pathway, including ameliorating ∆Ψm reduction, blocking mitochondrial Cyt C release, reducing Bax levels and increasing Bcl-2 levels, suppressing caspase-9 and caspase-3 activation in cytoplasmic fractions. Moreover, the components of MXF that act on the heart are mainly ephedra alkaloids and aconitine alkaloids. CONCLUSIONS: The findings demonstrated that MXF treatment markedly reduced MCM cell apoptosis induced by thermal stimulation, which may be ascribed to the mitochondrial-mediated signaling pathway.

Metabolic engineering of Zymomonas moblis for ethylene production from straw hydrolysate.

Biological ethylene production is a promising sustainable alternative approach for fossil-based ethylene production. The high glucose utilization of Z. mobilis makes it as a promising bioethylene producer. In this study, Zymomonas mobilis has been engineered to produce ethylene through the introduction of the synthetic ethylene-forming enzyme (EFE). We also investigated the effect of systematically knocking out the competitive metabolic pathway of pyruvate in an effort to improve the availability of pyruvate for ethylene production in Z. mobilis expressing EFE. Guided by these results, we tested a number of conjectures that could improve the α-ketoglutarate supply. Optimization of these pathways and different substrate supplies resulted in a greater production of ethylene (from 1.36 to 12.83 nmol/OD600/mL), which may guide future engineering work on ethylene production using other organisms. Meanwhile, we achieved an ethylene production of 5.8 nmol/OD600/mL in the ZM532-efe strain using enzymatic straw hydrolysate of corn straw as the sole carbon source. As a preferred host in biorefinery technologies using lignocellulosic biomass as feedstock, heterologous expression of EFE in Z. mobilis converts the non-ethylene producing strain into an ethylene-producing one using a metabolic engineering approach, which is of great significance for the utilization of cellulosic biomass in the future. KEY POINTS: • Heterologous expression of EFE in Z. mobilis successfully converted the non-ethylene producing strain into an ethylene producer (1.36 nmol/OD600/mL). Targeted modifications of the central carbon metabolism can effectively improve ethylene production (peak production: 8.3 nmol/OD600/mL). • The addition of nutrients to the medium can further increase the production of ethylene (peak production: 12.8 nmol/OD600/mL). • The ZM532-efe strain achieved an ethylene production of 5.8 nmol/OD600/mL when enzymatic hydrolysate of corn straw was used as the sole carbon source.

Qualitative and Quantitative Analysis for the Chemical Constituents of Tetrastigma hemsleyanum Diels et Gilg Using Ultra-High Performance Liquid Chromatography/Hybrid Quadrupole-Orbitrap Mass Spectrometry and Preliminary Screening for Anti-Influenza Virus Components.

Tetrastigma hemsleyanum Diels et Gilg (T. hemsleyanums) is a kind of traditional folk medicinal plant which has been used widely in China for its antivirus, antitumor, and other clinical effects. In this study, ultra-high performance liquid chromatography coupled with hybrid quadrupole-orbitrap mass spectrometry (UPLC-Q-Exactive/MS) was utilized to analyze the chemical constituents of T. hemsleyanums. Fifty-one constituents were clarified, including flavonoids, anthraquinones, esters, fatty acids, phenols, and catechins. In the subsequent quantitative analysis, the contents of ten compounds of rutin, kaempferol, astragalin, quercitrin, quercetin, vitexin-rhamnoside, isorhamnetin, vitexin, emodin-8-O-ß-D-glucoside, and isoquercetin in 18 batches of T. hemsleyanums collected from different places of cultivation were determined. Meanwhile, anti-influenza virus bioactivity in vitro of the above samples was detected with Gaussia Luciferase viral titer assay. It was found that the antiviral bioactivity varied from batches to batches in accordance with content difference of the chemical constituents in T. hemsleyanums. Correlation analysis was performed with SPSS software for the association between LC-MS chemometrics and bioactivity of influenza virus inhibition, and 8 constituents of flavonoids showed positive correlation coefficient, which may provide a valuable clue for searching potential antiviral components in T. hemsleyanums.