Shotgun metagenomics reveals the gut microbial diversity and functions in Vespa mandarinia (Hymenoptera: Vespidae) at multiple life stages.

Wasps play important roles as predators and pollinators in the ecosystem. The Jingpo minority residing in Yunnan Province, China, has a traditional practice of using wine infused with mature wasps as a customary remedy for managing rheumatoid arthritis. The larva of the wasp is also a tasteful folk dish that has created a tremendous market. There is a paucity of survival knowledge, which has greatly restricted their potential applications in food and healthcare. Recent research has highlighted the importance of gut microbiota in insect growth. Nevertheless, there is still a lack of understanding regarding the composition, changes, and functions of the gut microbiota in Vespa mandarinia during development. In this research, the gut microbiota were investigated across three growth stages of Vespa mandarinia using a metagenomic technology. The result revealed that there are significant variations in the proportion of main gut microbes during the metamorphosis of Vespa mandarinia. Tenericutes were found to dominate during the larval stage, while Proteobacteria emerged as the dominant group post-pupation. Through a comprehensive analysis of the gut microbiota metagenome, this study revealed functional differences in the wasp gut microbiota at various growth stages. During the larval stage, the gut microbiota plays a central role in promoting metabolism. Following pupation, the gut microbiota exhibited diversified functions, likely due to the complex environments and diverse food sources encountered after metamorphosis. These functions included amino acid metabolism, compound degradation, and defense mechanisms. This research provides an extensive dataset on the gut microbiota during the metamorphosis of Vespa mandarinia, contributing to a deeper understanding of the influence of gut microbiota on wasp growth. Furthermore, this study uncovers a unique microbial treasure within insect guts, which is important for advancing the application of wasps in the fields of food and medicine.

The therapeutic effect of wasp venom (Vespa magnifica, Smith) and its effective part on rheumatoid arthritis fibroblast-like synoviocytes through modulating inflammation, redox homeostasis and ferroptosis.

ETHNOPHARMACOLOGICAL RELEVANCE: Rheumatoid arthritis (RA) is a chronic inflammatory disease that is related to the aberrant proliferation of fibroblast-like synoviocytes (FLS). Wasp venom (WV, Vespa magnifica, Smith), an insect secretion, has been used to treat RA in Chinese Jingpo national minority's ancient prescription. However, the potential mechanisms haven't been clarified. AIM OF THE STUDY: The purposes of this paper were two-fold. First, to investigate which was the best anti-RA effective part of WV-I (molecular weight less than 3 kDa), WV-II (molecular weight 3-10 kDa) and WV-III (molecular weight more than 10 kDa) that were separated from WV. Second, to explore the underlying molecular mechanism of WV and WV-II that was best effective part in RA. MATERIALS AND METHODS: The wasps were electrically stimulated and the secretions were collected. WV-I, WV-II and WV-III were acquired by ultracentrifuge method according to molecular weight. Next, WV, WV-I, WV-II and WV-III were identified by HPLC. Functional annotation and pathway analysis of WV used to bioinformatics analysis. RNA-seq analyses were constructed to identify differentially expressed genes (DEGs). GO and KEGG pathway analyses were performed by Metascape database. STRING was used to analyze the PPI network from DEGs. Next, PPI network was visualized using Cytoscape that based on MCODE. The pivotal genes of PPI network and MCODE analysis were verified by qRT-PCR. Subsequently, MH7A cells were performed by MTT assay to evaluate the ability of inhibiting cell proliferation. Luciferase activity assay was conducted in HepG2/STAT1 or HepG2/STAT3 cells to assess STAT1/3 sensitivity of WV, WV-I, WV-II and WV-III. Additionally, interleukin (IL)-1ß and IL-6 expression levels were detected by ELISA kits. Intracellular thioredoxin reductase (TrxR) enzyme was evaluated by TrxR activity assay kit. ROS levels, lipid ROS levels and Mitochondrial membrane potential (MMP) were assessed by fluorescence probe. Cell apoptosis and MMP were measured by using flow cytometry. Furthermore, the key proteins of JAK/STAT signaling pathway, protein levels of TrxR and glutathione peroxidase 4 axis (GPX4) were examined by Western blotting assay. RESULTS: RNA-sequencing analysis of WV displayed be related to oxidation-reduction, inflammation and apoptosis. The data displayed that WV, WV-II and WV-III inhibited significantly cells proliferation in human MH7A cell line compared to WV-I treatment group, but WV-III had no significant suppressive effect on luciferase activity of STAT3 compared with IL-6-induced group. Combined with earlier reports that WV-III contained major allergens, we selected WV and WV-II further to study the mechanism of anti-RA. In addition, WV and WV-II decreased the level of IL-1ß and IL-6 in TNF-α-induced MH7A cells via inactivating of JAK/STAT signaling pathway. On the other hand, WV and WV-II down-regulated the TrxR activity to produce ROS and induce cell apoptosis. Furthermore, WV and WV-II could accumulate lipid ROS to induce GPX4-mediated ferroptosis. CONCLUSIONS: Taken together, the experimental results revealed that WV and WV-II were potential therapeutic agents for RA through modulating JAK/STAT signaling pathways, redox homeostasis and ferroptosis in MH7A cells. Of note, WV-II was an effective part and the predominant active monomer in WV-II will be further explored in the future.

QSAR study of phenolic compounds and their anti-DPPH radical activity by discriminant analysis.

Phenolic compounds (PCs) could be applied to reduce reactive oxygen species (ROS) levels, and are used to prevent and treat diseases related to oxidative stress. QSAR study was applied to elucidate the relationship between the molecular descriptors and physicochemical properties of polyphenol analogues and their DPPH radical scavenging capability, to guide the design and discovery of highly-potent antioxidant substances more efficiently. PubMed database was used to collect 99 PCs with antioxidant activity, whereas, 105 negative PCs were found in ChEMBL database; their molecular descriptors were generated with Python's Rdkit package. While the molecular descriptors significantly related to the antioxidant activity of PCs were filtered by t-test. The prediction QSAR model was then established by discriminant analysis, and the obtained model was verified by the back-substitution and Leave-One-Out cross-validation methods along with heat map. It was revealed that the anti-DPPH radical activity of PCs was correlated with the drug-likeness and molecular fingerprints, physicochemical, topological, constitutional and electronic property. The established QSAR model could explicitly predict the antioxidant activity of polyphenols, thus were applicable to evaluate the potential of candidates as antioxidants.

Griseaketides A-D, New Aromatic Polyketides from the Pathogenic Fungus Magnaporthe grisea.

Magnaporthe grisea is the causal agent of rice blast disease, which is the most serious disease of cultivated rice. Aromatic polyketides are its typical metabolites and are involved in the infection process. In the search for novel lead compounds, chemical investigation of the fungus M. grisea M639 has led to the isolation of four new aromatic polyketides (salicylaldehyde skeleton bearing an unsaturated side chain), griseaketides A-D (1-4), as well as 15 known compounds (5-19). The structures of the new compounds were elucidated on the basis of extensive spectroscopic analyses, including HR-MS, 2D NMR. Compound 12 showed prominent activity that killed 94.5% of C. elegans at 400 ppm and 66.9% at 200 ppm over 24 h. This is the first report describing the nematicidal activity of this type aromatic polyketide.

Antibacterial diketopiperazines from an endophytic fungus Bionectria sp. Y1085.

Two new diketopiperazines (1, 2), one new polyprenol (3), together with 19 known compounds (4-22) were obtained from the EtOAc extract of Bionectria sp. Y1085, an endophytic fungus isolated from the plant Huperzia serrata. Their structures were elucidated by extensive NMR and MS analysis. Bionectin D (1) is a rare diketopiperazine with a single methylthio substitution at the α-carbon of cyclized amino acid residue. The antibacterial activity of compounds was assayed against Escherichia coli, Staphylococcus aureus, and Salmonella typhimurium ATCC 6539, and some metabolites (1, 2, 10, 11, and 14) exhibited evident antibacterial activity.

Absolute configuration determination of asarinin by synchrotron radiation with crystalline sponge method.

The determination of the absolute configuration of natural products still faces many challenges, especially the active pharmaceutical ingredient which is trace, oily and novel structures. Currently, NMR requires chiral reagents in determining the absolute configuration; ECD involves theoretical calculations and requires chromophores. In this study, the absolute configuration of asarinin had successfully identified by using synchrotron radiation with crystalline sponge method and combining MS with NMR. This method could identifying the crystal structure of trace amorphous substances, resolving the problem of absolute configuration of multi-chiral central compounds, and hopefully providing a new idea and approach for structural elucidation of natural products.

New secondary metabolites from an engineering mutant of endophytic Streptomyces sp. CS.

In previous work, a series of bioactive natural products had been isolated from the plant endophytic Streptomyces sp. CS, which was isolated from Maytenus hookeri. To mine new active metabolites, we describe introducing an alien carbamoyltransferase (asm21) gene into the strain CS by conjugal transfer. As a result, three recombinatorial mutants named CS/asm21-1, CS/asm21-2 and CS/asm21-4 were successfully constructed. Three mutants and wild type CS were cultured on solid medium, and the extracts were detected and analyzed by liquid chromatography-mass spectrometry (LC-MS). The LC-MS profiles showed several unknown peaks that were present in the spectra of extracts of the CS/asm21-4 cultured on oatmeal solid medium. Then, three new naphthomycins O-Q (1-3), a new macrolide hookerolide (4) as well as nine known compounds were obtained from the solid cultured medium. Their structures were identified by spectra data. These new compounds showed moderate antimicrobial activities.

The discovery of a freezing-induced peptide ligation during the total chemical synthesis of human interferon-ε.

A counterintuitive freezing-induced peptide ligation was discovered during the total synthesis of human interferon-ε (hIFN-ε) which blocks HIV infection through unique mechanisms. The successful synthesis of hIFN-ε (187 amino acids) in this research laid the foundation for related anti-AIDS drug development. Moreover, alanine mutation based on sequence alignment to solve the maldistribution of the ligation site and freezing-induced dominant conformation that facilitates peptide ligation are expected to be helpful for the synthesis of macrobiomolecules.

Phytochemistry and pharmacology of the genus Leonurus: The herb to benefit the mothers and more.

Plants belonging to the genus Leonurus, also named motherwort, are traditionally used for anti-gynecological disorder in East Asia, and for sedative in Europe. Chemical investigation of the genus Leonurus not only enriched the natural products library, but also enlarged the pharmacological application of this traditional herb. In this review, we systematically summarized the structures of 259 compounds isolated from the genus Leonurus, featured with 147 labdane diterpenoids. The reported bioactivity studies up to 2017 are presented in the second part, with the main focus on the isolated compounds and also concerning the extracts. In addition to the traditional uterine contraction and sedative activity, recently the cardiovascular protection effect of leonurine has drawn most attention. Other than that, neuroprotection, anti-inflammation, anti-cancer, anti-platelet aggregation and many other activities have been assigned to various compounds from the genus Leonurus. Among 70 bioactivity references cited in this review, 57% of them were concentrated on two alkaloids (leonurine and stachydrine), whereas only 20% are about the 147 diterpenoids. Anti-inflammation is the major bioactivity discovered so far for the labdane diterpenoids from the genus Leonurus, whose further therapeutic potential still remains for exploration.

Design and synthesis of an immobilized metal affinity chromatography and metal oxide affinity chromatography hybrid material for improved phosphopeptide enrichment.

Reversible phosphorylation of proteins is one of the most important post-translational modifications, while the detection of phosphopeptides is difficult due to their low abundance and the signal suppression of nonphosphorylated peptides. Therefore, selective enrichment of phosphopeptides from highly complicated mixtures is vital for MS-based phosphoproteome analysis. Despite various strategies have been developed, there is no single method that is capable of providing full coverage of the whole phosphoproteome. Metal oxide affinity chromatography (MOAC) enrichment preferably singly phosphopeptides, whereas immobilized metal affinity chromatography (IMAC) enrichment bias towards multiply phosphopeptides. In this study, first example of IMAC and MOAC hybrid material, Fe3O4@nSiO2@mSiO2/TiO2-Ti4+ nanoparticles were successfully synthesized for the enrichment of phosphopeptides with the aim to combining their advantages for enrich both mono- and multi-phosphorylated species. The TiO2 was firstly coated on the surface of mesoporous silica and then grafted with 3-(trihydroxysilyl)propyl methylphosphonate (THPMP) to chelate Ti4+ ions. This novel type of hybird material with high surface areas (179.3m2/g) exhibited good adsorption capacity (133mg/g) towards standard tryptic digest of ß-casein and the method based on this material also showed good sensitivity (4pmol). The synthesized Fe3O4@nSiO2@mSiO2/TiO2-Ti4+ microspheres were further used to selectively enrich phosphopeptides from complex biosamples, seven mono-phosphopeptides and eight multi-phosphopeptides were successfully enriched from nonfat milk which is much better than single IMAC or MOAC strategy. Those results indicated that Fe3O4@nSiO2@mSiO2/TiO2-Ti4+ microspheres have potential applications in MS-based phosphoproteomics to enlarge phosphoproteomics coverage and this work was expected to open up a promising strategy which combined the advantages of various methods in one material for effective enrich phosphorylated peptides.

Rapid, sensitive and selective HPLC-MS/MS method for the quantification of topically applied besifloxacin in rabbit plasma and ocular tissues: Application to a pharmacokinetic study.

Besifloxacin is a fourth-generation broad-spectrum fluoroquinolone registered for the topical treatment of bacterial conjunctivitis. In this study, a rapid, sensitive and selective liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed for quantification of besifloxacin in rabbit plasma and ocular tissues using nateglinide as the internal standard (IS). The analyte and IS were separated on a Sepax GP-Phenyl column by isocratic elution with methanol-acetonitrile-5 mM ammonium formate-formic acid (29:55:16:0.1, v/v/v/v) as the mobile phase at a flow rate of 1.2 mL/min, and the total run time was 3.0 min. An electrospray ionization (ESI) source was applied and operated in the positive ion mode; multiple reaction monitoring (MRM) mode was used for quantification, and the monitored transitions were 394.2→377.1 for besifloxacin and m/z 318.3→166.1 for the IS. The calibration curve was linear over the range of 0.103-206 ng/mL for plasma and 2.06-2060 ng/mL for tears, aqueous humor, conjunctiva and cornea with correlation coefficient (r) greater than 0.99. The lower limit of quantification (LLOQ) for besifloxacin was 0.103 ng/mL for plasma and 2.06 ng/mL for other ocular tissues with good accuracy and precision. Intra- and inter-batch precision were both lower than 15% and accuracy ranged from 85% to 115% at all QC levels. The method was successfully applied to the pharmacokinetic study of besifloxacin in rabbit plasma and ocular tissues after single and multiple topical administrations.

Chemical constituents from Euphorbia wallichii and their biological activities.

One rare diterpenoid which was an unusual phorbol derivative possessing a 5-ene-7-oxo functional group, wallichiioid A (1), and 17 known compounds (2-18) were isolated from the aerial parts of Euphorbia wallichii. The structures and relative configuration of these compounds were elucidated on the basis of extensive spectroscopic interpretation. All the known compounds were isolated from E. wallichii for the first time. Diterpenoids 1-5 were tested for their cytotoxicity against five cancer cell lines (A-549, MCF-7, Hep G2, HeLa, and P388) and showed IC(50) values in the range of 8.19-29.72 µg/mL. The antiangiogenic activities of diterpenoids 1-5 were also evaluated using a zebrafish model.

Three new prenylated flavonoids from Macaranga denticulata and their anticancer effects.

One rare flavonoid-diterpene heterodimer, denticulatain C (1), one modified geranyl-type side chain substituted flavonoid, denticulatain D (2) and one geranylated flavonoid, denticulatain E (3), as well as 11 known compounds (4-14) were isolated from the fronds of Macaranga denticulata. Their structures were elucidated on the basis of extensive spectroscopic interpretation. Compounds 4 and 8 inhibited the proliferation of A-549 cell line with IC50 values of 48.6 and 20.2 µg/mL, respectively. Compounds 3, 6, and 8 exhibited significant antiangiogenic activity on a zebrafish model with IC50 values of 9.78, 0.34, and 2.55 µg/mL, respectively.

Cytotoxic prenylated flavonoids from Macaranga indica.

Three new prenylated flavonoids, macarindicins A-C (1-3), as well as seven known compounds (4-10) were isolated from the twigs of Macaranga indica. Their structures were elucidated on the basis of extensive spectroscopic interpretation. Compounds 2 and 3 enriched the diversity of prenyl moiety in genus Macaranga especially in the aspect of various lengths of prenyl chain. All the known compounds were isolated from M. indica for the first time and this plant was found to contain large number of ellagic acid. Compounds 1-10 were tested for their cytotoxicity against four cancer cell lines (MCF-7, Hep G2, Hela and P388) and showed IC50 values in the range of 2.61-20.35 µg/mL.

Simultaneous LC-MS/MS determination of five tripterygium pyridine alkaloids in dog plasma and its application to their pharmacokinetic study after oral administration of tripterygium glycosides tablets.

A sensitive and selective liquid chromatography tandem mass spectrometric method was developed and validated for the simultaneous determination of five pyridine alkaloids contained in tripterygium glycosides tablets (triptolide, wilforine, wilforgine, wilfording and wilfortrine) in dog plasma. The analysis was carried out on a Sepax GP-Phenyl column using a mixture of methanol and 10mmol/L ammonium formate buffer solution containing 0.1% formic acid (75:25, v/v) as the mobile phase pumped at a flow-rate of 1.0mL/min. All MS data were obtained in the positive ESI mode with selective multiple reaction monitoring of ion transitions. The method was fully validated to be accurate and precise with a linear range of 0.2-1000ng/mL for triptolide and 0.05-1000ng/mL for the other four pyridine alkaloids. The intra-day and inter-day precisions (relative standard deviation, RSD, %) were within 10.6% and 14.0%, respectively, and the relative error (RE, %) were all less than 13.1%. The method was successfully applied to multi-components pharmacokinetic study of the five pyridine alkaloids in beagle dogs after a single oral administration of 3mg/kg and 30mg/kg tripterygium glycosides tablets, respectively, and a multiple oral administration of 30mg/kg for 6 consecutive days.

Minor Prenylated Flavonoids from the Twigs of Macarangaadenantha and Their Cytotoxic Activity.

Three new minor prenylated flavonoids, named macadenanthins A-C (1-3), together with three known ones (4-6), were isolated from the twigs of Macaranga adenantha. Their structures were elucidated on the basis of extensive spectroscopic analysis including NMR, UV and MS. The prenyl moieties in compounds 1-3 were further modified by cyclization and hydroxylation. The new compounds were tested for their cytotoxicity against four cancer cell lines (MCF-7, Hep G2, Hela and P388) and showed IC50 values in the range of 13.76-22.27 µM.

Cytotoxic prenylated bibenzyls and flavonoids from Macaranga kurzii.

One unique prenylated bibenzyl, kurzphenol A (1), two new prenylated flavonoids, kurzphenols B and C (2 and 3), as well as fourteen known compounds (4-17) were isolated from the twigs of Macaranga kurzii. Compound 1 was the first example of prenylated bibenzyl which possesses a benzofuran ring. All the known compounds were isolated from M. kurzii for the first time. Their structures were elucidated on the basis of extensive spectroscopic interpretation. Compounds 1-17 were tested for their cytotoxicity against A-549 and Hep G2 cancer cell lines and showed IC50 values in the range of 9.76-30.14 µg/mL.

Chemical constituents from Euphorbia stracheyi and their biological activities.

Three new diterpenoids, stracheyioids A-C (1-3), as well as 36 known compounds (4-39) were isolated from the whole plants of Euphorbia stracheyi. Compound 1 was a rare 13-deoxy tigliane diterpenoid and compound 2 was an ingenol diterpenoid characterized by an unique 2Z,4Z-decadienoyl acidic moieties. All the known compounds were isolated from E. stracheyi for the first time. Their structures were elucidated on the basis of extensive spectroscopic interpretation. Compounds 1-39 were tested for their cytotoxicity against five cancer cell lines (A-549, MCF-7, Hep G2, Hela and P388) and showed IC50 values in the range 6.64-42.86 µM. The antiangiogenic activities of the isolated compounds were also evaluated using a zebrafish model.

Jatropholane-type diterpenes from Euphorbia sikkimensis.

Four new jatropholane-type diterpenes (1-4), named sikkimenoids A-D, were isolated from the aerial parts of Euphorbia sikkimensis. The structural elucidations of 1-4 were accomplished by extensive NMR analyses, and their absolute configurations were established by ECD calculations. Compound 2 exhibited weak antiangiogenic activity with an IC(50) value of 43.0 µM when evaluated using a zebrafish model.

[Chemical constituents of Euphorbia sikkimensis].

Sixteen compounds were isolated from the aerial parts of Euphorbia sikkimensis by means of various chromatographic techniques such as silica gel, Sephades LH-20 and RP-18, and their structures were elucidated as naringenin (1), kaempferol (2), quercetin (3), kaempferol-3-O-alpha-L-arabinopyranoside (4), quercetin-3-O-alpha-L-arabinopyranoside (5), quercetin-3-O-(2"-galloyl)-alpha-L-arabinopyranoside (6), 5alpha, 8alpha-epidioxy-(22E, 24R)-ergosta-6,22-dien-3beta-ol (7), stigmast-5-ene-7-one-3beta-ol (8), 3beta-hydroxy4a, 14alpha-dimethyl-5alpha-ergosta-8, 24(28)-dien-7-one(9), beta-sitosterol (10) , 10-cucurbitadienol( 1) , scopoletin(12) , ethyl gallate(13), p-hydroxybenzaldehyde (14), 3 betahydroxybenzeneethanol( 15) ,and 2,4-dihydroxy-6-methoxy-acetophenone (16) on the basis of spectroscopic data analysis. All the compounds are isolated from this plant for the first time, and compounds 1, 4-8, 15 are obtained from Euphorbia species for the first time.