The metabolites produced by complex and diverse microorganisms are important resources for drug research and development. Using new targets to screen microbial metabolites, many anti-cancer drugs acting on different targets are discovered. Anti-tumor antibiotics acting on various targets and signaling pathways are important members in the study of specific targets for anti-tumor, and some anticancer antibiotics with potent antitumor activity are used as "warheads" of antibody-drug conjugates. Microbial-derived anti-tumor substances acting on different targets with high-efficiency "warheads" molecules are reviewed to provide a literature basis for research on the anti-cancer drugs for specific targets derived from microorganisms.

Due to the potent bactericidal activity and low incidence of drug resistance, the novel cyclic lipopeptide antibiotic - daptomycin has emerged as one of the first line antimicrobial agents in the treatment of serious infections caused by gram-positive resistant pathogens. This review summarizes the research advances of daptomycin in recent years, mainly including spectrum of antimicrobial activity, biosynthesis, mode of action, mechanism of drug resistance, structure-activity relationships, surotomycin and siderophore-daptomycin conjugate to kill multidrug resistant Acinetobacter baumannii. The findings summarized in this review highlight the directions of next-generation of daptomycin derivatives.

With the worldwide spread of multi-drug resistant (MDR) bacteria, bacterial resistance has become a major issue affecting human health. Although traditional methods for obtaining antibiotics by screening bacterial strains have found the most available antibiotics for us, this method has resulted in fewer and fewer antibiotics in the past few decades and is increasingly difficult to find the new structure of the compound entity. At present, there are few drugs that can fight super-resistant bacteria in the clinic or even research. therefore, the development and application of new technologies to address the issue of bacterial resistance is imminent. Since the first bacterial genome was sequenced more than 20 years ago, a large number of bacterial genomic sequence information can provide clues for the discovery of new antibiotics. In this review, we briefly outline the available data sources and highlight the use of genomic mining and metagenomics in discovery of new antibiotics.

Macrolide antibiotics have been widely utilized in the treatment of bacterial infections due to their strengths, low toxicity, and high efficacy. Because of the widespread application of macrolide drugs, the emergence of antibacterial resistance against antibiotics has become prominent. Ketolides, as the third generation macrolides, display improvement in activities against macrolide-resistant pathogens with broad antibacterial spectrum. Due to hepatotoxicity, the use of telithromycin has been limited. It is urgent to identify the novel sources of ketolides. So the structural modification of ketolides become the main research field of macrolide. This review introduces the recent progress in the structural modification of ketolide, with the purpose of providing support to development of new ketolide antibiotics.

Anti-tumor antibiotics exhibit great application potential in the anti-tumor therapy. Some drugs have become the first-line medication clinically. However, there are always various problems associated with anti-tumor antibiotics, such as poor solubility and instability as well as severe systemic side effects. It is important to choose suitable delivery carriers for a reasonable delivery system for a good targeting ability, enhanced anti-tumor efficacy and reduced adverse effects of the anti-tumor antibiotics, especially in the smart delivery systems. This review summarizes the carriers and the advances in the delivery systems of anti-tumor antibiotics, including anti-tumor antibiotic drugs currently on the market, in the clinical research stage and in the basic research stage.

Shikimate kinase is a key protein of the shikimic pathway, which is essential for the survival of Mycobacterium tuberculosis. In this study, a screening assay for Mycobacterium tuberculosis shikimate ki-nase (MtSK) inhibitor was developed. A 120 000-compound library was screened by the enzyme assay and the phenotype screening using Mycobacterium smegmatis. A hit compound named IMB-T5297[(E)-3-(3-(3-chloro-5-methoxy-4-(prop-2-yn-1-yloxy)phenyl)acryloyl)-6-methyl-2H-pyran-2, 4(3H)-dione] was identified to be a selective inhibitor of MtSK with a half maximal inhibitory concentration (IC₅₀) value of 1.745 μg·mL^-1, which also showed antibacterial activity. The interaction between compound and protein was analyzed by surface plasmon resonance (SPR) experiment, which showed the K_D value was 2.151×10^-5 mol·L^-1. The binding model of MtSK and compound was simulated by the computer program. Five key amino acids in the binding pocket were indispensable site-directed mutated to verify the model. IMB-T5297 inhibited Mycobacterium tuberculosis H37Rv with a minimum inhibitory concentration (MIC) value of 49.723 μg·mL^-1 and displayed low cytotoxicity to mammalian cells. In this study, IMB-T5297 was identified as a selective inhibitor of MtSK enzyme with anti-tuberculosis activity. With additional structural modification, the compound has a potential to become a novel anti-tuberculosis compound.

9-Acetoxycycloberberine (1) with a unique skeleton was first identified to display a potent antimicrobial profile against methicillin-resistant Staphylococcus aureus (MRSA) with MIC values of 1-16 μg·mL^-1. Taking the compound as a lead, 14 target cycloberberine analogues with diverse structures, such as berberine and chelerythrine derivatives, were synthesized and evaluated for their anti-bacterial activities. Analysis of the structure-activity relationship revealed that:① ring E was essential for the activity; ② the removing of ring B decreased the activity against MRSA. However, the antimicrobial activity against vancomycin-resistant Enterococcus faecium (VRE) was improved; ③ the introduction of a suitable rigid substituent at the 9-position was beneficial for the activity. Among them, compound 9a showed the most potential activity against methicillin-sensitive Staphylococcus aureus (MSSA) and MRSA isolates with MIC values of 0.5-1 μg·mL^-1, suggesting a different mechanism from clinical drugs. It displayed higher stability in blood. Therefore, we consider 9a worthy of further investigation. The results provide key scientific evidence for development of such compounds into a new type of anti-MRSA candidates.

Sansanmycins (SSs), produced by Streptomyces sp. SS, belong to uridyl peptide antibiotics which exhibit a good inhibitory effect on Mycobacterium tuberculosis and Pseudomonas aeruginosa. They share a unique chemical scaffold with a 4', 5'-enamide-3'-deoxyuridine attached to DABA (N-methyl-2, 3-diaminobutyryl) which was located in the peptide chain through peptide bond. In order to study the function of related genes and to employ synthetic biology to gain new SS derivatives, we obtained a complete SS biosynthetic gene cluster and heterologously expressed it in Streptomyces coelicolor M1146, M1152 and M1154. Fermentation broth of the recombinant strains were detected using HPLC and HPLC-MS/MS, and the result showed that SS-A was successfully produced in the three strains, and its production level in S. coelicolor M1154 was similar to the original wild type strain. In addition, a potential SS analogue named as SS-1154 was discovered from the fermentation broth of S. coelicolor M1154.

Circular RNA (circRNA) is a non-coding closed-loop single-stranded RNA molecule lacking the 5' end cap and the 3' poly (A) tail. Circular RNA is more abundant and stable than linear mRNA, and its expression is more conservative and specific. circRNA regulates cancer development through a variety of mechanisms, including miRNA sponges, regulating gene transcription, regulating RNA-binding proteins, and protein translation. This review summarizes the role of circRNA in cancer and helps to develop new clinical diagnostic techniques and treatments.

Aquaporin 1 (AQP1), the first water channel protein discovered among the aquaporin family, is a hydrophobic transmembrane protein involved in transcellular water movement. Recent evidence shows that AQP1 plays a role in tumor cell proliferation and migration, angiogenesis and tumor development and progression, representing a potential therapeutic target. In this review, we discuss the structures, functions and inhibitors of AQP1, as well as the involvement of AQP1 in tumor development and progression.

Chinese medicines (CM)-induced liver injury is one of the severe adverse drug reactions (ADRs) in clinical application, which restricts new drug research and development (R&D), clinical safe usage and industry development of CM. The issue, to elucidate the causality between liver injury and CM, is either a globally challenging problem or the precondition of CM safety evaluation. However, owing to the complexicity of CM and various influencing factors to CM-induced liver injury, the causality assessment for CM is much difficult, compared to synthetic drugs. Besides, the current assessment methods, primarily designed for clinical diagnosis, are difficult to be used in new drug R&D of CM. Hereinto, we reviewed the current ADR causality methods and proposed a new strategy called integrated evidence chain-based causality assessment method for CM-induced liver injury. The new causality method is designed for new drug R&D based on the complexicity of CM, to provide methodology in scientific assessment of causality of CM-induced liver injury and to promote success rate of new drug R&D. The new method could also raise our ability to find, avoid and prevent the risk of CM-induced liver injury.

Metabolomics data contains multiple variables usually processed and evaluated by means of principal components analysis. The statistical analysis of the multivariate data is involved in abstract, elusory fitting for the model of hyperspace, complicated theoretical arithmetic and sophisticated transformation of the data matrix. It is crucially important to understand the arithmetic mechanism and the properties of the models fully. In this article, we reviewed the key and puzzling issues in principal components analysis of the metabolomics data, including the principal components, the scores and loadings of a principal components, scaling and weighting, partial least square projection to latent structures, partial least squares discriminant analysis, orthogonal projection to latent structure, orthogonal bidirectional projections to latent structures, S-plot, shared and unique structure plot, and the validation of the model. Hopefully, this article provides a better understanding of data processing mode, model selection, procedure standardization, and data interpretation for a reliable conclusion.

Poly(ADP-ribose) polymerase (PARP)-1 and PARP2 function as ADP-ribosylases involved in DNA repair. PARP1/2 is highly expressed in cancers and emerged as an attractive target for antitumor drug. In this study, we investigated the antitumor activity of a novel PARP1/2 inhibitor YHP-743 in vitro and in vivo. The results showed that YHP-743 had potent enzymatic inhibitory activity against PARP1 and PARP2 to down-regulate the PAR level. YHP-743 not only inhibited breast cancer cells with genes deficiency of homologous recombination repair, but also potentiated chemotherapy agent's cytotoxicity, such as temozolomide, topotecan, cisplatin and doxorubicin. YHP-743 elicited good antitumor activity in combination with temo-zolomide in vivo.

In this study, azvudine (FNC), hydrochloride salt of azvudine (FNC-HCl) and triphosphate azovudine (FNC-TP) were tested against DENV-Ⅱ recombinant virus (DENV-Ⅱ Luc⁺). The inhibitory activity of FNC, FNC-HCl and FNC-TP on DENVs were detected by plaque assay. The effect on the expression of DENV-Ⅱ envelope protein E was detected by Western blot; the inhibitory of DENV-Ⅱ viral RNA by compounds was detected by real-time quantitative PCR. MTT assay was used to determine the cytotoxicity of the three compounds on Vero cells. The results showed that FNC, FNC-HCl and FNC-TP inhibited the viral replication by inhibition of renilla luciferase activity of DENV-Ⅱ Luc⁺. The 50% effective concentration (EC₅₀) of FNC, FNC-HCl and FNC-TP in the inhibition of DENVs replication were from 0.54-25.42 μmol·L^-1, while that of ribavirin was 40.78 ±1.02 μmol·L^-1 as the positive control. Western blot and real time quantitative PCR results showed that FNC, FNC-HCl and FNC-TP significantly inhibited the expression of DENV-Ⅱ E protein, and the replication of DENV-Ⅱ viral RNA. The 50% cytotoxic concentrations of FNC, FNC-HCl and FNC-TP were all greater than 3 000.00 μmol·L^-1. The results suggest that in vitro anti-DENVs activities of FNC, FNC-HCl and FNC-TP are superior to ribavirin, which are expected to become new candidates of anti-DENV drugs.

This study was designed to investigate the role of CD36 in palmitic acid (PA)-induced apoptosis of astrocytes and the potential mechanisms of the action. MTT assay was used to detect cell viability and TUNEL assay to detect cell apoptosis. It was found that PA significantly decreased astrocyte cell viability and increased cell apoptosis. The uptake of BODIPY FL C16 by astrocytes was measured by flow cytometry. The results showed that CD36 played a key role in the process of PA uptake by astrocytes. The changes of intracellular calcium concentration were detected by FLIPR real-time fluorescence recording system. It was found that IP3R mediated PA signal to induce intracellular calcium release and finally caused endoplasmic reticulum calcium depletion. The intracellular ROS level was detected with CM-H₂DCFDA fluorescence staining. The ROS level was induced by PA in astrocytes. The effect was blocked by CD36 inhibitor SSO through inhibition of the uptake of PA. PA-induced calcium overload and ROS increase were prevented by IP3R inhibitor APB. SSO, APB and antioxidant NAC all had significant inhibitory effects on PA-induced astrocyte cell viability decrease. In conclusion, CD36 mediates the translocation of PA into astrocytes, which leads to calcium overload, oxidative stress and eventually cell apoptosis.

Ginsenoside Rg1 is a common component of a variety of stroke and diabetes medications, but its anti-stroke effect in diabetic patients is unclear. The aim of this research is to test the therapeutic effect of Rg1 on ischemic stroke in diabetic rats, and elucidate the effect of Rg1 on post-stroke neuro-inflammation. Rg1 significantly reduced the infarct area percent, increased the behavioral score, and reduced the brain water content in diabetic rats after stroke in the diabetic rats. Rg1 reduced the post-stroke inflammatory response and decreased the expression of high mobility group box1 (HMGB1) protein significantly. Elevated level of HMGB1 activity by supplementing exogenous HMGB1 protein abolished the anti-stroke effect of Rg1, which suggests that HMGB1 is involved into the anti-stroke effect of Rg1 in the diabetic rats.

Transient receptor potential vanilloid member 3 (TRPV3) is a temperature-sensitive cation channel protein, which contributes to nociception, itch, hair growth, emotional control and the pathophysiology of migraine. However, research progress on TRPV3 fundamental molecular biology is rather slow, compared to other TRP channels due to the lack of its selective antagonists. It's necessary to identify TRPV3 selective antagonists for the study on TRPV3 physiological functions. In this study, several selective TRPV3 antagonists were identified by ligand-based virtual screening of shape-based similarity and electrostatic matching. The most potent one (V-39) blocked 2-APB-activated currents in a stable human TRPV3 expressed HEK293T cell line with IC₅₀=18.0 ±1.1 μmol·L^-1 (n=4). Besides, the interaction pattern between TRPV3 and its antagonists were studied through docking the antagonists into a homology model (TRPV3_HM4) generated from the crystal structure of TPRV1. The docking results show that the binding site of TRPV3 locates between linker domain (of N-terminus and TM1) and TRP Box. There are a π-π stacking interaction and hydrogen bonding interactions between compound V-39 and residues His-310, His-314 and Arg-577 of the pocket. Identification of these antagonists provides new probes for understanding the pharmacological function of TRPV3 channel.

The chemical constituents of the fruits of Chaenomeles sinensis (Thouin) Koehne were investigated using chromatographic methods, including Diaion HP-20, Toyopearl HW-40, MCI Gel CHP-20, ODS, Silica gel chromatography and semi-preparative-HPLC. Three compounds were isolated and their structures were elucidated with spectral data and physicochemical properties, which were identified as chaenomeles alkaloid A (1), ginsenine (2) and 1, 2, 3, 4-tetrahydro-1-methyl-β-carboline-3-car-boxylic acid (3). Among those, compound 1 is a new alkaloid, compound 2 and 3 were isolated from this plant for the first time. To investigate the protective effect of compounds 1-3 on Rat adrenal pheochromocytoma (PC-12) injury induced by the β-amyloid protein (Aβ_25-35). The results show that compounds 2 and 3 have a significant protective effect on the PC12 cells exposed to Aβ_25-35.

To compare static and dynamic metabolomics data analysis of CUMS (chronic unpredictable mild stress)-induced depression, GC-MS spectrometry was conducted on the plasma metabolome. S-Plot and ANOVA (analysis of variance)-simultaneous component analysis (ASCA) were respectively applied to static and dynamic analysis of metabolomics data. Static metabolomics data analysis revealed three typical plasma metabolites including propionic acid, D-allose, and 9, 12, 15-octadecatrienoic acid, while dynamic me-tabolomics data analysis found seven typical metabolites including propionic acid, D-allose, My-inositol, me-thylamine, etc. The abundances of typical metabolites observed by dynamic metabolomics data analysis were consistent with the variation trends of body weight and sugar water preference rate of CUMS rats. In conclusion, dynamic metabolomics analysis revealed more typical plasma metabolites, which have the potential to explain variations of body weight and behavior parameter of CUMS-induced depression rats. Combination of static and dynamic metabolomics data analysis may provide a strong support to the pathological study of complex diseases.

This study was designed to compare normal and diabetic rats in the pharmacokinetic and tissue distribution of honokiol and its metabolites. Type 2 diabetic rat model was established using high-fat diet feeding for 6 weeks followed by single intraperitoneal injection of low dose (30 mg·kg^-1) strepotozotocin. The concentration of honokiol and its metabolites were determined by high performance liquid chromatography. Pharmacokinetic parameters were calculated using DAS 3.0 software. The C_max of honokiol in the normal rats and diabetic rats are 872.5 ±233.1 and 614.7 ±182.4 μg·L^-1 respectively (P < 0.05), and the AUC are 3 827.2 ±926.9 and 3 004.7 ±391.4 μg·h·L^-1 respectively. Meanwhile, AUC_0-t and C_max of the metabolite M2 were significantly increased in diabetic rats. The concentrations of honokiol in liver, kidney and brain in the diabetic model group were higher than those of the normal control group. Meanwhile, the exposure of M1 in liver, M2 in liver and kidney of the model group were higher than that in the normal group. The data suggest that the pharmacokinetics and tissue distribution of honokiol and its metabolites are changed in the pathological state of diabetes.

In current study, adefovir dipivoxil (AD)-acetaminophen (AP) cocrystal (molar ratio, 1:1) was prepared by slow evaporation from acetonitrile, followed by physicochemical characterizations using differential scanning calorimetry, powder X-Ray diffraction and Fourier transform infrared spectroscopy. Molecular modeling showed that the phosphoester group of AD was connected with the amide group of AP through hydrogen bonds. In comparison to crystalline AD, the solubility and dissolution rate of AD from AD-AP cocrystal were significantly enhanced by 1.5-fold and 1.6-fold, respectively. In addition, based on the rat single-pass intestinal perfusion study, the permeabilities of AD in various intestinal sections (i.e., duodenum, jejunum, ileum and colon) were significantly improved (e.g., about 3-fold enhancement in duodenum) after cocrystallization with AP by inhibiting P-glyprotein mediated efflux of AD, which will benefit absorption in vivo and subsequent oral bioavailability of poorly permeable drug AD.

The therapeutic application of artemisinin (ART) is restricted in application due to its poor water solubility and stability. In this study, the long-circulating liposomes (L-Lip) were constructed to improve the solubility and stability of ART. The preparation method, physicochemical properties, serum stability, in vitro release profile and cytotoxicity of the ART loaded long-circulating liposomes were investigated. Using the particle size and entrapment efficiency (EE) as the evaluation index, the preparation procedure was optimized by the Box-Behnken response surface design based on the single factor screening method. The ART loaded long-circulating liposomes were prepared by filming rehydration method, and evaluated with particle size and entrapment efficiency. The optimal formulation was as follows:lipid-cholesterol=5.22:1 (mass ratio), drug-lipid=1:23.15 (mass ratio), lipid concentration=14.35 mg·mL^-1, and molar percentage of mPEG=2%. The morphology of L-Lip was uniformly spherical shape according to optimal formulation. The mean size and polydispersity index (PDI) were about (113.3 ±4.7) nm and 0.227 ±0.022 respectively, the zeta potential was (-12.9 ±2.6) mV, and the entrapment efficiency (EE) of ART was (95.88 ±4.8)%. The L-Lip had good stability at 4℃ for 15 days and the particle sizes did not exhibit significant variations in 50% rat plasma over 24 h at 37℃. The in vitro release study of formulation showed a sustained release. Moreover, the cytotoxicity exhibited that blank liposomes were of great safety. Compared with the free ART, the liposome formulation achieved lower cytotoxicity at the high concentration. The L-Lip successfully prepared by a simple filming-rehydration method exhibited ideal physicochemical properties and were enhanced safety, which may sever as a promising nanoplatform for clinical application.

As a common Tibetan herb, Bawo Sebo was mainly used in the treatment of rheumatoid arthritis and urarthritis in Traditional Tibetan medicine. Based on our ethnobotanical survey, the origin of the herb was determined as Swertia verticillifolia T. N. Ho et S. W. Liu (Gentianaceae), endemic to the region of the Qinghai-Tibet Plateau. The diagnostic characters:perennial; stem leaves in whorls; corolla campanulate, yellow-green, 4-lobed; nectary 1 per corolla lobe, naked. Also, its complete chloroplast (cp) genome was sequenced. It is 151 682 bp in length, including a large single copy (LSC) region of 82 623 bp, a small single copy (SSC) region of 18 335 bp and a pair of inverted repeats (IRs) of 25 362 bp. It contains 129 unique genes, including 84 protein-coding genes, 37 tRNAs and 8 rRNAs. This study provides information for understanding the diversity of Swertia cp genomes, and the alpine species identification, conservation and molecular phylogenetic researches of Swertia and Gentianaceae.