Latest ArticlesThree sesquiterpenoids were isolated from the dichloromethane extract of the roots of Stelleropsis tianschanica Pobed through a combination of various chromatographic approaches, including silica gel, Sephadex LH-20, reverse phase C18 and so on. On the basis of spectroscopic data analysis, they were identified as (+)-guaia-l(10), ll-dien-9-one-5α-hydroxy (1), 4β, 5βH-guai-9, 7(11)-dien-12, 8-olide-1α, 8α-diol (2), 4α, 5βHguai-9, 7(11)-dien-12, 8-olide-1α, 8α-diol (3). The compound 1 is a new sesquiterpenoid, and the compound 3 was isolated for the first time from the genus Stelleropsis.
The impact of statins on airway inflammation has not yet been established and it may differ from their cholesterol-lowering effects. Oral administration of statins at large-doses may have adverse effects. It is possible to overcome the side effect to increase the clinical efficacy through the inhalation route. Female BALB/c mice were randomly divided into four groups including the control group (NS-vehicle), model group[ovalbumim (OVA)-vehicle], simvastatin (Sim) group and dexamethasone (DXM) group at 10 mice in each group. In this study, we hypothesize Sim as a potential anti-inflammatory drug with biological and pharmacokinetic properties suitable for delivery through the inhalation route. Mice were immunized with OVA and then challenged with OVA aerosol to induce the asthma reaction. Sim was inhaled at a dosage (5 mg ·mL-1, ih, 15 min) or administrated by intraperitoneal injection (40 mg·kg-1, ip) or gavage (40 mg·kg-1, ig) during the OVA-challenge. In the mouse model of asthma, Sim significantly attenuated the total inflammatory cell counts and eosinophil counts (P < 0.01 or P < 0.05) via the different routes. Pretreatment with Sim at 1, 5, 20 mg·mL-1, ih, significantly decreased the total inflammatory cell counts and eosinophil counts in alveolar lavage fluid (BALF) (P < 0.01) and the inhibitory effect was increased with the dosages of Sim via inhalation. Both of DXM and Sim at 5, 20 mg·mL-1, ih, were more potent than that of Sim at 1 mg·mL-1, ih. Sim significantly decreased IL-4 and IL-5 mRNA expression of lung at 5, 20 mg·mL-1, ih (P < 0.01 or P < 0.05). Sim (5, 20 mg·mL-1, ih) significantly decreased levels of IL-4 and IL-5 in BALF (P < 0.01 or P < 0.05). However, Sim (1 mg·mL-1) declined slightly on IL-4 level in BALF. Sim at 5, 20 mg·mL-1 had a greater rate of decline in IL-5 than at 1 mg·mL-1. These results suggest Sim with different doses as a potential anti-inflammatory drug for airway inflammatory diseases with properties suitable for delivery by inhalation, which probably overcome the side effects and low clinical efficacy of oral Sim.
Poly(2-ethyl-2-oxazoline) (PEOz), a hydrophilic long-chain polymer synthesized by living cationic ring-opening isomerization polymerization of 2-ethyl-2-oxazoline, has the characteristics of low toxicity, biocompatibility, flexible chain, and modified expediently. PEOz is a potential substitute of polyethylene glycol (PEG) to render the ability of long-circulation, enhance cellular uptake and endosomal escape behaviors to PEOz modified drug delivery system. In this review, we summarized recent literature for the research progress of physicochemical properties, synthetic methods and the application of PEOz in drug delivery system.
Increasing evidence suggests that hepatocellular carcinomas (HCCs) are sustained by a distinct subpopulation of self-renewing cells known as cancer stem cells (CSC). However, our understanding of their regulation is limited. Rapid reversible changes of CSC-like cells within tumors may result from the effect of biological mediators found in the tumor microenvironment. This paper aims to explore how nitrite, a key cellular modulator whose level is elevated in many tumors, affects CSC-like phenotypes of human hepatoma cells SMMC-7721 cells. The SMMC-7721 cell line was cultured under serum-free conditions to produce floating spheres. The distribution of cell cycle was analyzed by flow cytometry, the capability of cells self-renew was detected by colony-forming capabilities and spheroid-formation assay, the expression of stemness protein such as CD133, CD90 and EpCAM were determined by flow cytometry and Western blot, cell invasion was analyzed by transwell assay, and viability of SMMC-7721 parental cells and spheroids cancer cells was determined by the 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay. Xenograft tumor models were established by subcutaneously injecting SMMC-7721 spheroids cancer cells, the transplanted tumor tissue ROS levels was detected by reactive oxygen species (ROS) test kits, the expression of HIF-1α was observed by immunofluorescence. Our results showed that the SMMC-7721 spheroid cells were enriched with CSCs properties, indicated by the ability to self-renew, increased expression of CSCs markers, and increased resistance to chemotherapeutic drugs. Additionally, SMMC-7721 parental cells and spheroids cancer cells were treated with 150 μmol·L-1 sodium nitrite for 6 days, compared with control cells, an increased accumulation of G0/G1 phase cells was observable in treatment cells. Indeed, our data demonstrated that in parent cells and spheres cells that were treated with sodium nitrite for different time, the cells' ability to chemoresistance and invasion, clone-forming efficiencies and the spheres forming ability were significantly higher than that of control cells. Exposure of sodium nitrite regulated CSC-like phenotype, indicated by increased expression of known CSC markers, CD133, CD90 and EpCAM in the exposed parental cells, as well as in dormant spheroids cancer cells. Compared with the parent cells, the above effects of nitrite on the spheres cells were significantly enhanced. In vivo data also presented a more significant promotion of tumor xenograft growth from the nitrite treatment than from either of the control. Mechanistic analysis indicated that nitrite induced the upregulation of HIF-1α as well as the downregulation of ROS in the tumor microenvironment. These results suggest that nitrite increases the invasiveness of SMMC-7721 cells through up-regulation of tumor stemness.
The glucose consumption activity of 9-substitued analogues of berberine was evaluated in L6 myotubes. It was found that the introduction of an ethoxy group on the 9-position of berberine was beneficial for the activity. 9-Ethoxy berberine analogue 2a exhibited superior activity to berberine in multiple dose levels, and the activity of 2a was 5.4 times as high as that of berberine at the dose of 1.25 μmol·L-1. At the meantime, the potency on AMPK activation of 2a was 2.8 times of that of berberine at the dose of 10 μmol·L-1. Therefore, the compound 2a is a promising scaffold for further modification.
The chemical constituents of Dioscorea opposite Thunb. were isolated and purified by Diaion HP-20, Sephadex LH-20, Toyopearl HW-40, MCI Gel CHP-20, ODS, silica gel column chromatography and semi-preparative-HPLC. Nine compounds were found and their structures were elucidated by spectral data and physicochemical properties, which were identified as 2-(1', 2', 3'-trihydroxybutyl-4'-O-α-D-glucopyranoside)-6-(2", 3", 4"-trihydroxybutyl)-pyrazine (1), uracil (2), xanthine (3), hypoxanthine (4), thymine (5), adenosine (6), uridine (7), inosine (8), and 5'-deoxy-5'-methylsulphinyladenosine (9). The compound 1 is a new pyrazine derivative, and the compound 3-5, 8, 9 are found in this plant for the first time.
The difference in pH between apical and basolateral side of intestinal epithelial and pH dependence character of the combination of FcRn (neonatal Fc receptor) and ligand might improve the delivery of hydrophobic drugs by facilitating the transcytosis of nanocarriers. Here we designed FcBP (IgG Fc domain-binding peptides) decorated coumarin 6 (C6) loaded poly(ethyl ethylene phosphate)-co-poly(ε-caprolactone) (PEG-PCL) micelles with different ligand densities to study the effect of pH and ligand density on the endocytosis and exocytosis process of micelles on human colon adenanocaricinoma cell lines (Caco-2). Active micelles with different ligand densities and passive micelles were prepared using the thin-film hydration method. The size of the micelles was characterized by dynamic light scattering analysis and the morphology was observed by transmission electron microscope. The endocytosis and exocytosis of the micelles at pH 7.4 and pH 6.0, as well as the effect of FcRn on the endocytosis, were investigated by flow cytometry. The results showed that the size of micelles was about 30 nm, which was not affected by FcBP decoration. We found that pH and ligand density could both influence the endocytosis. The uptake of active micelles was higher at pH 6.0 than at pH 7.4, and an optimal ligand density of endocytosis was appeared in both pH environment. Then we proved that FcBP decorated micelles could be endocytosed at pH 6.0 and exocytosed at pH 7.4, and the exocytosis process was also related to ligand density. Micelles with 10% ligand density had the largest exocytosis, showing the potentiality to deliver drugs through the intestinal epithelial. In addition, the competitive inhibition experiments illustrated that the interaction between FcRn and FcBP were essential to endocytosis. The results will enhance the understanding on the FcBP decorated PEG-PCL micelles for transmemberane drug delivery.
Bromodomain and extraterminal (BET) proteins are a class of proteins that can interpret epigenetic codes and play an important role in regulating gene transcription through identifying and binding acetylated histones or non-histones proteins. The BET inhibitors have emerged with good therapeutic effects in preclinical disease models such as cancer and inflammation. Some of them have entered clinical studies, demonstrating that there is considerable prospect for drug development with BET as a potential therapeutic target. This review briefly describes the structures and functions of the BET proteins, the BET inhibitors in various diseases, as well as molecular mechanisms involved.
This study was designed to investigate the synergistic analgesic effect between choline (Cho) and acetaminophen (Ace). Mice were treated with 0.6% acetic acid solution by intraperitoneal injection to build acetate writhing model. The KM mice were randomly divided into four groups:control group (n=10), Cho group (n=50), Ace group (n=50), combination group (Cho+Ace group, n=40), then the writhing times were counted respectively. OriginPro8.5 was used to calculate ED 50. The isobolographic analysis was used to test the interaction of Cho and Ace. To explore the mechanism, forty KM mice were randomly divided into control group, Cho group, Ace group and Cho + Ace group. Blood was collected for detection of TNF-α, IL-6, PGE2 and NF-κB content using ELISA kits. The result ED 50 was calculated as followings. ED50 of Cho and Ace was 19.47 mg·kg-1 and 20.56 mg·kg-1. The concentrations were 2.94 mg·kg-1 for Cho and 3.15 mg·kg-1 for Ace in the combination test. The levels of TNF-α, IL-6, PGE2 and NF-κB in Cho group and Ace group were lower than those in the control group (P < 0.05). Compared to the Cho group and Ace group, the levels of TNF-α, IL-6, PGE2, NF-κB in Cho + Ace group were reduced further (P < 0.05). The results revealed that Cho and Ace have synergistic analgesic effects, which may associate with inhibition of the NF-κB signaling pathway.
To a certain extent, the drug effect is determined by its blood concentration. It is generally accepted that the blood concentrations of constituents of Chinese medicines are very low. There is no sufficient experimental bases and references on its degree and the possibility of taking effect. In this study, 69 papers were collected and analyzed by searching the database of Scifinder, Pubmed, CNKI. The minimum effective blood concentrations of 73 common Western medicines and the maximum blood concentrations of 211 in vivo constituents of 40 Chinese medicines (single herb or compound Chinese medicine) were summarized. It was found that the maximum blood concentrations of the most in vivo constituents of Chinese medicines were much less than the minimum effective blood concentrations of the Western medicines. Specifically, the minimum effective blood concentrations of 17 Western medicines (23% of total) and the maximum blood concentrations of the 143 in vivo constituents of Chinese medicines (68% of total) were less than 100 ng ·mL-1; the minimum effective blood concentrations of 31 Western medicines (42% of total) and the maximum blood concentrations of the 20 in vivo constituents of Chinese medicines (9% of total) were more than 1 000 ng·mL-1. In this paper, a systematic summary and comparison of the blood concentrations in traditional Chinese medicines and Western medicines were conducted, which could provide a new ideas and references for the study of the pharmacodynamical material basis and its mechanism in traditional Chinese medicine.