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.

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.

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.

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.

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.

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.

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.

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.

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.

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.