Molecular characterization and structure basis of a malonyltransferase with both substrate promiscuity and catalytic regiospecificity from Cistanche tubulosa.

Enzymatic malonylation of natural glycosides provides a promising alternative method for drug-like malonylated glycosides supply. However, the catalytic potential and structural basis of plant malonyltransferase are far from being fully elucidated. This work identified a new malonyltransferase CtMaT1 from Cistanche tubulosa. It displayed unprecedented mono- and/or di-malonylation activity toward diverse glucosides with different aglycons. A "one-pot" system by CtMaT1 and a malonyl-CoA synthetase was established to biosynthesize nine new malonylated glucosides. Structural investigations revealed that CtMaT1 possesses an adequately spacious acyl-acceptor pocket capable of accommodating diverse glucosides. Additionally, it recognizes malonyl-CoA through strong electrotactic and hydrogen interactions. QM/MM calculation revealed the H167-mediated SN2 reaction mechanism of CtMaT1, while dynamic simulations detected the formation of stable hydrogen bonds between the glucose-6-OH group and H167, resulting in its high malonylation regiospecificity. Calculated energy profiles of two isomeric glycosides highlighted lower reaction energy barriers towards glucoside substrates, emphasizing CtMaT1's preference for glucosides. Furthermore, a mutant CtMaT1H36A with notably increased di-malonylation activity was obtained. The underlying molecular mechanism was illuminated through MM/GBSA binding free energy calculation. This study significantly advances the understanding of plant acyltransferases from both functional and protein structural perspectives, while also providing a versatile tool for enzymatic malonylation applications in pharmacology.

Early diagnosis of aspiration pneumonia by gastrointestinal ultrasound combined with lung ultrasound.

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Enzymatic biosynthesis of novel 2-(2-phenylethyl)chromone glycosides catalyzed by UDP-glycosyltransferase UGT71BD1.

2-(2-Phenylethyl)chromones (PECs) are the main bioactive components of agarwood which showed diverse pharmaceutical activities. Glycosylation is a useful structural modification method to improve compounds' druggability. However, PEC glycosides were rarely reported in nature which largely limited their further medicinal investigations and applications. In this study, the enzymatic glycosylation of four naturally separated PECs 1-4 was achieved using a promiscuous glycosyltransferase UGT71BD1 identified from Cistanche tubulosa. It could accept UDP-Glucose, UDP-N-acetylglucosamine and UDP-xylose as sugar donors and conduct the corresponding O-glycosylation of 1-4 with high conversion efficiencies. Three O-glucosylated products 1a (5-hydroxy-2-(2-phenylethyl)chromone 8-O-ß-D-glucopyranoside), 2a (8-chloro-2-(2-phenylethyl)chromone 6-O-ß-D-glucopyranoside) and 3a (2-(2-phenylethyl)chromone 6-O-ß-D-glucopyranoside) were prepared and structurally elucidated as novel PEC glucosides based on NMR spectroscopic analyses. Subsequent pharmaceutical evaluation found that 1a showed remarkably improved cytotoxicity against HL-60 cells, whose cell inhibition rate was 19 times higher than that of its aglycon 1. The IC50 value of 1a was further determined to be 13.96 ± 1.10 µM, implying its potential as a promising antitumor-leading candidate. To improve the production of 1, docking, simulation and site-directed mutagenesis were performed. The important role of P15 in the glucosylation of PECs was discovered. Besides, a mutant K288A with a two-fold increased yield for 1a production was also afforded. This research reported the enzymatic glycosylation of PECs for the first time, and also provide an eco-friendly pathway for the alternative production of PEC glycosides for leading compounds discovery.

Review of glucose oxidase as a feed additive: production, engineering, applications, growth-promoting mechanisms, and outlook.

The regulation and prohibition of antibiotics used as growth promoters (AGP) in the feed field are increasing because they cause antimicrobial resistance and drug residue issues and threaten community health. Recently, glucose oxidase (GOx) has attracted increasing interest in the feed industry as an alternative to antibiotics. GOx specifically catalyzes the production of gluconic acid (GA) and hydrogen peroxide (H2O2) by consuming molecular oxygen, and plays an important role in relieving oxidative stress, preserving health, and promoting animal growth. To expand the application of GOx in the feed field, considerable efforts have been made to mine new genetic resources. Efforts have also been made to heterologously overexpress relevant genes to reduce production costs and to engineer proteins by modifying enzyme properties, both of which are bottleneck problems that limit industrial feed applications. Herein, the: different sources, diverse biochemical properties, distinct structural features, and various strategies of GOx engineering and heterologous overexpression are summarized. The mechanism through which GOx promotes growth in animal production, including the improvement of antioxidant capacity, maintenance of intestinal microbiota homeostasis, and enhancement of gut function, are also systematically addressed. Finally, a new perspective is provided for the future development of GOx applications in the feed field.

Glycosylation of Aromatic Glycosides by a Promiscuous Glycosyltransferase UGT71BD1 from Cistanche tubulosa.

Multiple-glycosylated glycosides are a major source of bioactive leads. However, most of the currently reported glycosyltransferases (GTases) mainly catalyze glycosylation of aglycones without sugar group substitution. GTases accepting diverse glycosides as substrates are rarely reported. In this article, a new GTase UGT71BD1 was identified from Cistanche tubulosa, a desert herb plant abundant with various phenylethanoid glycosides (PhGs). Interestingly, UGT71BD1 showed no activity toward the aglycone of PhGs. Instead, it could catalyze the further glycosylation of PhG compounds to produce new phenylethanoid multiglycosylated glycosides, including the natural rarely separated tetraglycoside PhGs. Extensive assays found the unprecedented substrate promiscuity of UGT71BD1 toward diverse glycosides including flavonoid glycosides, stilbene glycosides, and coumarin glycosides, performing further mono- or diglycosylation with efficient conversion rates. Using UGT71BD1, six multiglycosylated glycosides were prepared and structurally identified by NMR spectroscopy. These products showed enhanced pharmacological activities compared with the substrates. Docking, dynamic simulation, and mutagenesis studies identified key residues for UGT71BD1's activity and revealed that the sugar modules in glycosides play crucial roles in substrate recognition, thus partly illuminating the unusual substrate preference of UGT71BD1 toward diverse glycosides. UGT71BD1 could be a potential enzyme tool for glycosylation of diverse glycosides.

MPEPE, a predictive approach to improve protein expression in E. coli based on deep learning.

The expression of proteins in Escherichia coli is often essential for their characterization, modification, and subsequent application. Gene sequence is the major factor contributing expression. In this study, we used the expression data from 6438 heterologous proteins under the same expression condition in E. coli to construct a deep learning classifier for screening high- and low-expression proteins. In conjunction with conserved residue analysis to minimize functional disruption, a mutation predictor for enhanced protein expression (MPEPE) was proposed to identify mutations conducive to protein expression. MPEPE identified mutation sites in laccase 13B22 and the glucose dehydrogenase FAD-AtGDH, that significantly increased both expression levels and activity of these proteins. Additionally, a significant correlation of 0.46 between the predicted high level expression propensity with the constructed models and the protein abundance of endogenous genes in E. coli was also been detected. Therefore, the study provides foundational insights into the relationship between specific amino acid usage, codon usage, and protein expression, and is essential for research and industrial applications.

Bedside critical ultrasound as a key to the diagnosis of obstructive atelectasis complicated with acute cor pulmonale and differentiation from pulmonary embolism: A case report.

Acute attack of dyspnea may be combined with acute cor pulmonale (ACP). Rapid and accurate identification of the etiology of ACP is the key to its diagnosis and treatment. Echocardiography is a better imaging tool in the assessment of right ventricular function. Under the guidance of the theory of cardiopulmonary interaction, ultrasonography can detect lung lesions, which causes ACP. We report the case of a 67-year-old man who received mechanical ventilation for acute respiratory failure. Right ventricular dysfunction was detected by echocardiography. Lung ultrasound showed a high risk of pulmonary embolism. However, obstructive atelectasis should not be ruled out after increasing back area ultrasonography. To avoid pitfalls, combined cardiac and lung ultrasound should be used carefully and strictly.

Enhancing the thermostability of transglutaminase from Streptomyces mobaraensis based on the rational design of a disulfide bond.

Transglutaminase (TGase), a transferase, is widely adopted in the food industry and other biological fields due to its unique characteristics of modifying proteins by intra- or intermolecular cross-linking. However, obtaining a mutant TGase that is highly thermostable and active would significantly aid in food processing. Therefore, this study sought to improve the thermostability of TGase by introducing an artificial disulfide bridge through a structure-based rational enzyme engineering approach. After the rational screening, six disulfide mutants (E139C/G143C, R146C/E149C, A182C/N195C, L200C/R208C, T223C/F226C, and E139C/G143C+L200C/R208C) of the transglutaminase gene from Streptomyces mobaraensis (Sm-TGase) were selected and constructed by rationally designed mutations in cysteine. Of them, a mutant (E139C/G143C) with enhanced thermostability was selected and characterized for further analysis. The results indicated that the mutant E139C/G143C had a similar specific activity, optimal temperature, and pH but a lower Km and higher Vmax than the wild-type. Its half-life (t1/2) at 55 °C was 10.7 min, which was 1.69-fold higher than the wild-type, while its melting temperature (Tm) was 3.52 °C higher than the wild-type. These results proved that the introduction of disulfide bonds into TGase by rational design could be an effective approach to improve the thermostability of TGase and other food enzymes for food processing.

ß-galactosidase GALA from Bacillus circulans with high transgalactosylation activity.

ß-galactosidase catalyzes lactose hydrolysis and transfers reactions to produce prebiotics such as galacto-oligosaccharides (GOS) with potential applications in the food industry and pharmaceuticals. However, there is still a need for improved transgalactosylation activity of ß-galactosidases and reaction conditions of GOS production in order to maximize GOS output and reduce production costs. In this study, a ß-galactosidase gene, galA, from Bacillus circulans was expressed in Pichia pastoris, which not only hydrolyzed lactose but also had strong transgalactosylation activity to produce GOS. Response surface methodology was adopted to investigate the effects of temperature, enzyme concentration, pH, initial lactose concentration, and reaction time on the production of GOS and optimize the reaction conditions for GOS. The optimal pH for the enzyme was 6.0 and remained stable under neutral and basic conditions. Meanwhile, GALA showed most activity at 50°C and retained considerable activity at a lower temperature 30-40°C, indicating this enzyme could work under mild conditions. The enzyme concentration and temperature were found to be the critical parameters affecting the transgalactosylation activity. Response surface methodology showed that the optimal enzyme concentration, initial lactose concentration, temperature, pH, and reaction time were 3.03 U/mL, 500 g/L, 30°C, 5.08, and 4 h, respectively. Under such conditions, the maximum yield of GOS was 252.8 g/L, accounting for approximately 50.56% of the total sugar. This yield can be considered relatively high compared to those obtained from other sources of ß-galactosidases, implying a great potential for GALA in the industrial production and application of GOS.

A narrative review of exploring potential salivary biomarkers in respiratory diseases: still on its way.

Saliva is abundant with proteins, metabolites, DNA, and a diverse range of bacterial species. During the past two decades, saliva has emerged as a novel diagnostic and evaluation medium for several diseases. Collection of saliva samples is simple, minimally invasive, and convenient even in infants, children, and patients with anxious. Furthermore, with the development of hypersensitive techniques [e.g., microsensor arrays, enzyme-labeled immunosensors, nanoparticle-labeled immunosensors, capacitive or impedimetric immunosensors, magneto immunosensors, field effect transistor immunosensors, and surface enhanced Raman spectroscopy (SERS)], the sensitivity and accuracy of saliva diagnostic procedures have been improved. Nowadays, saliva has been used as a potential medium for several disease diagnosis and assessment, such as periodontitis, caries, cancers, diabetes mellitus, and cardiovascular diseases. Saliva has been used widely for studying microbiomics, genomics, transcriptomics, proteomics, and metabolomics of respiratory diseases, however, the use of salivary biomarkers for the diagnosis, prognosis, and monitoring of respiratory disease is still in its infancy. Herein, we review the progress of research on salivary biomarkers related to several respiratory diseases, including bronchial asthma, chronic obstructive pulmonary disease (COPD), obstructive sleep apnea (OSA), pneumonia, tuberculosis (TB), Langerhans cell histiocytosis (LCH) and cystic fibrosis (CF). Furthermore, several limitations of saliva test such as the lack of standard protocol for saliva collection and reasonable reference values for saliva test are also mentioned in this review.

[Production of curcumin by engineered Escherichia coli].

Curcumin is exclusively isolated from Zingiberaceae plants with a broad spectrum of bioactivities. In the present study, we used the diketide-CoA synthase (DCS) and curcumin synthase (CURS) genes to construct a non-natural fusion gene encoding diketide-CoA synthase::curcumin synthase (DCS::CURS). This fusion protein, together with the acetyl coenzyme A carboxylase (ACC) and the 4-coumarate coenzyme A ligase (4CL), were introduced into Escherichia coli for the production of curcumin from ferulic acid. The process is divided into two stages, the growth stage using LB medium and the fermentation stage using the modified M9 medium. The yield of curcumin reached 386.8 mg/L by optimizing the induction of protein expression in the growth stage, and optimizing the inoculum volume, medium composition and fermentation time in the fermentation stage, as well as the addition of macroporous resin AB-8 into the second medium to attenuate the toxicity of the end product. The exploitation of the non-natural fusion protein DCS::CURS for the production of curcumin provides a new alternative to further promoting the production of curcumin and the related analogues.

Molecular cloning and biochemical characterization of a new coumarin glycosyltransferase CtUGT1 from Cistanche tubulosa.

UDP-glycosyltransferases (UGTs) are an important and functionally diverse family of enzymes involved in secondary metabolite biosynthesis. Coumarin is one of the most common skeletons of natural products with candidate pharmacological activities. However, to date, many reported GTs from plants mainly recognized flavonoids as sugar acceptors. Only limited GTs could catalyze the glycosylation of coumarins. In this study, a new UGT was cloned from Cistanche tubulosa, a valuable traditional tonic Chinese herb, which is abundant with diverse glycosides such as phenylethanoid glycosides, lignan glycosides, and iridoid glycosides. Sequence alignment and phylogenetic analysis showed that CtUGT1 is phylogenetically distant from most of the reported flavonoid UGTs and adjacent to phenylpropanoid UGTs. Extensive in vitro enzyme assays found that although CtUGT1 was not involved in the biosynthesis of bioactive glycosides in C. tubulosa, it could catalyze the glucosylation of coumarins umbelliferone 1, esculetine 2, and hymecromone 3 in considerable yield. The glycosylated products were identified by comparison with the reference standards or NMR spectroscopy, and the results indicated that CtUGT1 can regiospecifically catalyze the glucosylation of hydroxyl coumarins at the C7-OH position. The key residues that determined CtUGT1's activity were further discussed based on homology modeling and molecular docking analyses. Combined with site-directed mutagenesis results, it was found that H19 played an irreplaceable role as the crucial catalysis basis. CtUGT1 could be used in the enzymatic preparation of bioactive coumarin glycosides.

Successful treatment of acute circulatory failure of unknown cause using critical ultrasound-guided reverse fluid resuscitation: A case report.

RATIONALE: Fluid resuscitation manages shock effectively. However, shock is not always caused by hypovolemia; various types of shock have variable volumetric reactivity. Combined echocardiography and lung ultrasound (LUS) is a new technique for assessing volume status and pulmonary edema in these patients. We report a case of unexplained acute circulatory failure and acute kidney injury (AKI) aggravated by active fluid resuscitation. We used the critical consultation ultrasonic examination (CCUE) protocol for evaluation, and successfully revived the patient with reverse fluid resuscitation. PATIENT CONCERNS: An 82-year-old man with hypertension, atrial fibrillation, and left ventricular diastolic dysfunction (LVDD) was admitted with abdominal distention and lower extremity edema. He developed symptoms of acute circulatory failure, including low blood pressure, anuria, and skin spots. After positive fluid resuscitation, the blood pressure lowered further, and moist rales were audible over both lungs. DIAGNOSIS: We performed bedside critical ultrasound for evaluation. The differential diagnoses based on the findings included left atrial and right heart dilatation, low cardiac output owing to reduced left ventricular ejection consequent to excessive circulatory capacity, right heart dilation, and left ventricular compression, and pulmonary edema caused by volume overload. INTERVENTIONS: Infusion was withheld, and tracheal intubation and mechanical ventilation were instituted to assist breathing; reverse fluid resuscitation was initiated, using continuous renal replacement therapy (CRRT) to maintain a negative fluid balance. OUTCOMES: Within 72 hours of fluid withdrawal, the blood pressure reverted to normal, symptoms of pulmonary edema were alleviated, and the circulation and tissue perfusion were restored. The symptoms of acute renal injury are relieved and allowing urine formation without support. LESSONS: Not all patients with acute circulatory failure require positive fluid resuscitation. Fluid balance should be closely monitored and managed. Potential intolerance to the rapid increase in volume may lead to biventricular interaction, ultimately leading to acute circulatory failure. The shock caused by volume overload should be treated with reverse fluid resuscitation. Combined echocardiography and LUS is a powerful tool for the differential diagnosis of circulatory and respiratory dysfunction.

Rab27A promotes cellular apoptosis and ROS production by regulating the miRNA-124-3p/STAT3/RelA signalling pathway in ulcerative colitis.

Ulcerative colitis (UC) is a multifactorial inflammatory disease, and increasing evidence has demonstrated that the mechanism of UC pathogenesis is associated with excessive cellular apoptosis and reactive oxygen species (ROS) production. However, their function and molecular mechanisms related to UC remain unknown. In this study, Rab27A mRNA and protein were proven to be overexpressed in intestinal epithelial cells of UC patients and DSS-induced colitis mice, compared with control (P < 0.05). And Rab27A silencing inhibits inflammatory process in DSS-induced colitis mice (P < 0.05). Then, it was shown that knockdown of Rab27A suppressed apoptosis and ROS production through modulation of miR-124-3p, whereas overexpression of Rab27A promoted apoptosis and ROS production in LPS-induced colonic cells. In addition, enhanced expression of miR-124-3p attenuated apoptosis and ROS production by targeting regulation of STAT3 in LPS-induced colonic cells. Mechanistically, we found Rab27A reduced the expression and activity of miR-124-3p to activate STAT3/RelA signalling pathway and promote apoptosis and ROS production in LPS-induced colonic cells, whereas overexpression of miR-124-3p abrogated these effects of Rab27A. More importantly, animal experiments illustrated that ectopic expression of Rab27A promoted the inflammatory process, whereas overexpression of miR-124-3p might interfere with the inflammatory effect in DSS-induced colitis mice. In summary, Rab27A might modulate the miR-124-3p/STAT3/RelA axis to promote apoptosis and ROS production in inflammatory colonic cells, suggesting that Rab27A as a novel therapeutic target for the prevention and treatment of UC patients.

Role of Melatonin in Arbuscular Mycorrhizal Fungi-Induced Resistance to Fusarium Wilt in Cucumber.

Melatonin is a multifunctional molecule that confers tolerance to a number of biotic and abiotic stresses in plants. However, the role of melatonin in plant response to Fusarium oxysporum and the interaction with arbuscular mycorrhizal fungi (AMF) remain unclear. Here we show that exogenous melatonin application promoted the AMF colonization rate in cucumber roots, which potentially suppressed Fusarium wilt as evidenced by a decreased disease index and an increased control effect. Leaf gas exchange analysis revealed that Fusarium inoculation significantly decreased the net photosynthetic rate (Pn), stomatal conductance (Gs), intercellular CO2 concentrations (Ci), and transpiration rate (Tr). Intriguingly, either melatonin application or AMF inoculation significantly increased the Pn, Gs, Tr, and dry biomass, and their combined treatment showed a more profound effect under Fusarium stress. Further analysis showed that Fusarium induced oxidative stress as evidenced by increased lipid peroxidation and electrolyte leakage. Conversely, either melatonin or AMF drastically attenuated the levels of malondialdehyde, H2O2, and electrolyte leakage in Fusarium-inoculated plants, and their combined treatment caused a further decrease. Fusarium inoculation decreased the activity and transcripts of superoxide dismutase and ascorbate peroxidase, and the content of glutathione and proline. Besides, the activity and transcripts of peroxidase and catalase, the content of phenols and flavonoids increased after Fusarium infection. Importantly, melatonin and/or AMF significantly increased those parameters with the greatest effect with their combined treatment under Fusarium stress. Our results suggest that a positive collaboration between melatonin and AMF enhances resistance to Fusarium wilt in cucumber plants.

Dopamine alleviates bisphenol A-induced phytotoxicity by enhancing antioxidant and detoxification potential in cucumber.

Bisphenol A (BPA) is an emerging organic pollutant, widely distributed in environment. Plants can uptake and metabolize BPA, but BPA accumulation induces phytotoxicity. In this study, we administered dopamine, a kind of catecholamines with strong antioxidative potential, to unveil its role in cucumber tolerance to BPA stress. The results showed that exposure to BPA (20 mg L-1) for 21 days significantly reduced growth and biomass accumulation in cucumber seedlings as revealed by decreased lengths and dry weights of shoots and roots. While BPA exposure decreased the chlorophyll content, cell viability and root activity, it remarkably increased reactive oxygen species (ROS) accumulation, electrolyte leakage and malondialdehyde (MDA) content, suggesting that BPA induced oxidative stress in cucumber. However, exogenous dopamine application significantly improved the photosynthetic pigment content, root cell viability, growth and biomass accumulation, and decreased the ROS and MDA levels by increasing the activity of antioxidant enzymes under BPA stress. Further analysis revealed that dopamine application significantly increased the glutathione content and the transcripts and activity of glutathione S-transferase under co-administration of dopamine and BPA compared with only BPA treatment. Moreover, dopamine decreased the BPA content in both leaves and roots, suggesting that dopamine promoted BPA metabolism by enhancing the glutathione-dependent detoxification. Our results show that dopamine has a positive role against BPA phytotoxicity and it may reduce the risks-associated with the dietary intake of BPA through consumption of vegetables.

Trichoderma asperellum reduces phoxim residue in roots by promoting plant detoxification potential in Solanum lycopersicum L.

Phoxim, a broad-spectrum organophosphate pesticide, is widely used in agriculture to control insect pests in vegetable crops as well as in farm mammals. However, the indiscriminate use of phoxim has increased its release into the environment, leading to the contamination of plant-based foods such as vegetables. In this study, we investigated the effect of Trichoderma asperellum (TM, an opportunistic fungus) on phoxim residue in tomato roots and explored the mechanisms of phoxim metabolism through analysis of detoxification enzymes and gene expression. Degradation kinetics of phoxim showed that TM inoculation rapidly and significantly reduced phoxim residues in tomato roots. Phoxim concentrations at 5d, 10d and 15d post treatment were 75.12, 65.71 and 77.45% lower in TM + phoxim than only phoxim treatment, respectively. The TM inoculation significantly increased the glutathione (GSH) content, the activity of glutathione S-transferase (GST) and the transcript levels of GSH, GST1, GST2 and GST3 in phoxim-treated roots. In addition, the activity of peroxidase and polyphenol peroxidase involved in the xenobiotic conversion also increased in TM + phoxim treatment. The expression of detoxification genes, such as CYP724B2, GR, ABC2 and GPX increased by 3.82, 3.08, 7.89 and 2.46 fold, respectively in TM + phoxim compared with only phoxim. Similarly, the content of ascorbate (AsA) and the ratio of AsA to dehydroascorbate increased by 45.16% and 57.34%, respectively in TM + phoxim-treated roots. Our results suggest that TM stimulates plant detoxification potential in all three phases (conversion, conjugation and sequestration) of xenobiotc metabolism, leading to a reduced phoxim residue in tomato roots.

Enhancing thermostability of a psychrophilic alpha-amylase by the structural energy optimization in the trajectories of molecular dynamics simulations.

The cold-adapted alpha-amylase (PHA) from Pseudoalteromonas haloplanktis is a psychrophilic enzyme which demonstrates high activity at low temperatures, but poor thermostability. Most of the method only employed the crystal structure to design the target protein. However, the trajectory of protein molecular dynamics (MD) simulation contained clues about the protein stability. In this study, we combined MD simulation and energy optimization methods to design mutations located at non-conserved residues. Two single point mutants (S255K, S340P) and one integrated mutant (S255K/S340P) enhanced thermostability without affecting the optimal catalytic activity. After incubation at 40 °C for 80 min, the residual activities of mutants S255K, S340P and S255K/S340P were 1.6-, 2.4-, and 2.6-fold greater than that of the wild type (WT). Additionally, the catalytic efficiency values (kcat/Km) of S255K, S340P, and S255K/S340P also increased 1.9-, 2.0-, and 2.7-fold when compared to WT.

[Isolation and identification of endophytic fungi from Huperzia serrata and their metabolites' inhibitory activities against acetylcholinesterase and anti-inflammatory activities].

A total of 27 endophytic fungal strains were isolated from Huperzia serrata,which were richly distributed in the stems and leaves while less distributed in roots. The 27 strains were identified by Internal Transcribed Spacer( ITS) r DNA molecular method and one of the strains belongs to Basidiomycota phylum,and other 26 stains belong to 26 species,9 general,6 families,5 orders,3 classes of Ascomycota Phylum. The dominant strains were Colletotrichum genus,belonging to Glomerellaceae family,Glomerellales order,Sordariomycetes class,Ascomycota Phylum,with the percentage of 48. 15%. The inhibitory activities of the crude extracts of 27 endophytic fungal strains against acetylcholinesterase( ACh E) and nitric oxide( NO) production were evaluated by Ellman's method and Griess method,respectively. Crude extracts of four fungi exhibited inhibitory activities against ACh E with an IC50 value of 42. 5-62. 4 mg·L~(-1),and some fungi's crude extracts were found to inhibit nitric oxide( NO) production in lipopolysaccharide( LPS)-activated RAW264. 7 macrophage cells with an IC50 value of 2. 2-51. 3 mg·L~(-1),which indicated that these fungi had potential anti-inflammatory activities.The chemical composition of the Et OAc extract of endophytic fungus HS21 was also analyzed by LCMS-IT-TOF. Seventeen compounds including six polyketides,four diphenyl ether derivatives and seven meroterpenoids were putatively identified.

MiR-216a inhibits proliferation and promotes apoptosis of human airway smooth muscle cells by targeting JAK2.

Objective: Accumulating evidence suggests that aberrantly expressed microRNAs in airway smooth muscle (ASM) cells could change airway remodeling during the development of asthma. However, the underlying functions of microRNAs in ASM cell proliferation and apoptosis need to be further elucidated. Methods: By using RT-qPCR, miR-216a expression level was examined in the asthmatic patients and non-asthmatic individuals. Cell proliferation assay and flow cytometry analysis were used in ASM cells in which miR-216a was an abnormal expression. MiR-216a predicted to target gene was explored by bioinformatic software, and further analyzed by Western blotting and luciferase reporter assay. Results: Our results demonstrated that miR-216a levels were considerably lower in the ASM cells of asthmatic patients than in those of non-asthmatic individuals. Further study verified that the overexpression of miR-216a markedly suppressed cell proliferation and promoted cell apoptosis, whereas the knockdown of miR-216a had opposite effects in ASM cells. In addition, luciferase reporter assays and Western blotting identified that JAK2 was the direct functional target of miR-216a, and the ectopic expression of JAK2 partially rescued the inhibitory effect of miR-216a in ASM cells. Conclusions: The above data indicate that miR-216a may function as a key regulator of airway remodeling by targeting JAK2, thus suggesting the potential role of miR-216a in the pathogenesis of asthma.