Latest ArticlesUrate transporter 1 (URAT1) is a validated target for the treatment of hyperuricemia. Based on the structure of URC-102, which is currently under a phase Ⅱ clinical trial, fourteen novel analogs were designed and synthesized. Among them, four compounds (9b, 9c, 10e and 10g) exhibited substantial inhibitory effect against URAT1. The most active compound 9b showed an IC50 value of 0.061 μmol·L-1, which is significantly more potent than Lesinurad and Benzbromarone. Preliminary SAR was drawn, providing clues for further structural optimization.
The grading and quality analysis methods for different commercial Glycyrrhiza Polygalae Radix slices were established. The qualities of different grade samples were analyzed and compared, in order to provide useful information for the formulation of the grading standards of Glycyrrhiza Polygalae Radix slices. A total of 34 batches of Glycyrrhiza Polygalae Radix slice samples collected from 12 companies were divided into two grades:first-grade (diameter ≥ 3.0 mm) and second-grade (diameter < 3.0 mm). Thin-layer chromatography (TLC), multi-component content determination and fingerprint analysis were used to analyze the qualities of different grades of Glycyrrhiza Polygalae Radix slices, and the fingerprints were statistically analyzed using partial least squares-discriminant analysis (PLS-DA) and orthogonal partial least squares-discriminant analysis (OPLS-DA). The results showed that the established TLC method can simultaneously identify three major types of components, including sugar esters, xanthones, and saponins in Glycyrrhiza Polygalae Radix slices, and has obvious advantage compared to the existing methods for its rich information, low cost, and easy or safe operation. The multi-component determination showed that the contents of three index components (polygalaxanthone Ⅲ, 3, 6'-disinapoyl sucrose and tenuifolin) in the first-grade products of Glycyrrhiza Polygalae Radix slices were lower than those in the second-grade products. The results of PLS-DA and OPLS-DA indicated significant differences were observed between the first-grade and second-grade products, with sibiricose A5, sibiricose A6, polygalaxanthone Ⅲ, 3, 6'-disinapoyl sucrose and tenuifoliside A being identifies as the major differentiate markers.
This study was designed to investigate the effect on tumor growth inhibition activity of lizards (Gekkoswinhonis Guenther) with different extent of broiling. Samples were prepared by a traditional drying method combined with broiling on clay tiles. Four groups of samples were all dried before broiling. Group A was without broiling; group B was mildly broiled; group C was moderately broiled; and group D was heavily broiled. Crispiness was detected by the sizes of the generated fragments of different groups and crispiness increased with broiling. Sensory evaluation of vision and olfaction was performed, and scores were generated by evaluators. Moderately broiled group had the highest total score in sensory evaluation. Water content and content of water-soluble extracts were detected according to Chinese Pharmacopoeia. With the increasing broiling extent, content of water-soluble extracts increased while water content decreased. Soluble protein concentration was detected by bicinchoninic acid (BCA) kit and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) with the same crude drug content. Soluble protein concentration decreased with the increasing broiling extent. With equal loading of proteins at the same concentration, soluble protein diversity was detected by SDS-PAGE. Band difference was marked by red boxes. Soluble protein molecule weights showed significant difference with the increasing broiling extent. H22 tumor-bearing mice model was established and used to detect tumor growth inhibition rate and immune organ index. Life quality of mice was evaluated. Mice treated with Gekkoswinhonis Guenther had better appetites and higher average weights compared with positive control group treated with fluorouracil (5-FU). Animal experiments were approved by the Ethics Committee of Beijing University of Chinese Medicine. Group A had the highest tumor growth inhibition rate (34.11%), followed by Group B (29.14%) and Group D (28.43%), Group C (21.98%) had the lowest tumor growth inhibition rate, but sensory evaluation was on the contrary. These results indicated that moderately broiling improved sensory evaluation but reduced the tumor growth inhibition activity of Gekkoswinhonis Guenther. The best tumor growth inhibition activity appeared when water content was 7.71%.
The rat models of focal cerebral ischemic reperfusion and subarachnoid hemorrhage were used to evaluate the therapeutic effects of artificial musk to provide support for its clinical application. All animal experiments were performed following the regulations of the Animal Ethics Committee of Peking Union Medical College. The results showed that oral administration of artificial musk had significant protective effects on acute ischemic and hemorrhagic stroke. In the dose range of 10-200 mg·kg-1, the mortality, neurobehavioral and cerebral infarction volume of rats in model group indicated a clear dose dependent relationship. The effective dose of artificial musk is 10 mg·kg-1 in ischemic stroke and 200 mg·kg-1 in hemorrhagic stroke. These findings suggest that the treatments of artificial musk in ischemic stroke and in hemorrhagic stroke are different, and such differences should be noted for its clinical use.
In this study, 13 xyloglucan endotransglycosylases/hydrolases (XTHs) and 8 expansin (EXPs) were screened from safflower floret transcriptome database. Through correlation analysis between the safflower gene expression profile chip and the corolla development, only 4 XTHs (CtXTH1-4) and 1 EXP (CtEXP1) have positive relevance with corolla elongation (r ≥ 0.60) and were therefore validated by qRT-PCR. The full length of these genes were cloned by RACE. According to the bioinformatic analysis, CtXTH1 correlated with the development of the floret, and the expression pattern analysis indicated that CtXTH1 had accumulated in the floret. The recombinant vector (pMT39-CtXTH1) was constructed for gene transformation. Overexpression of CtXTH1 significantly increased the corolla length (about 5.34% to 10.25%) and corolla weight (about 30.00% to 36.02%) in transgenic safflower. The overexpression lines also showed an increasing tendency in the weight of seeds, average number of corollas per cone and average number of seeds in each cone. Meanwhile, overexpression of CtXTH1 had no significant effect on flavonoids. According to the corolla microstructure, the OVX-line tubular part of floret exhibited a looser and irregular character. These data suggested that CtXTH1 can potentially increase relaxation of the tissues and boost corolla elongation. Our study provides a valuable clue for plant breeding in the future.
Myeloproliferative neoplasms (MPNs) result from clonal expansion of haematopoietic stem cells and are characterized by abnormal proliferation of myeloid lineage cells in the bone marrow. Sustained activation of JAK-STAT signaling pathway due to JAK2 phosphorylation is an important cause of MPNs, and mutation of JAK2 kinase can keep it in a state of continuous phosphorylation. The most typical mutation in JAK2 is a site mutation of V617F in the pseudokinase domain. The JAK2V617F-activating mutation is highly prevalent in MPNs, with frequencies estimated at approximately 95% in polycythaemia vera (PV) and 50% in primary myelofibrosis (PMF) and essential thrombocytosis (ET) patients. It is now clear that JAK2 is an important target for treatment of MPNs. Inhibiting aberrant activation of the JAK2-STAT signaling pathway has become a popular trend in research for effective treatment of MPNs. This review summarizes the research progress in developing JAK2 inhibitors for treatment of MPNs in recent years, including the new discoveries of the biological functions of JAK2, the relationship between JAK2 and MPN, and the status of development of JAK2 small molecule inhibitors.
Cyclophosphamide (CPA) is one of the most commonly used alkylating agents in the treatment of malignant cancer. CPA is metabolized by cytochrome P450 enzymes into 4-hydroxycyclophosphamide in vivo which can exhibit anti-tumor activity. Metabolic activation of CPA can cause adverse reactions such as myelosuppression, cystitis, and liver injury. The aim of this study was to evaluate the dynamic changes of hepatic injury induced by CPA in mice. Male BALB/c mice were injected CPA (200 mg·kg-1) intraperitoneally. Both serum and liver samples were collected at 0, 2, 6, 12 and 24 hours after dosing. The animal experiment protocol was approved by the Institutional Animal Care and Use Committee at Sun Yat-sen University. The results showed that hepatotoxicity was observed at 2 hours after CPA dosing, and the most serious liver injury was measured at 12 hours. The level of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) and malondialdehyde (MDA) was significantly increased, glutathione (GSH) level was significantly decreased, hepatocyte edema and vacuolar degeneration were widely observed in liver tissue, and began to recover 24 hours after dosing. In addition, due to oxidative stress damage caused by CPA, nuclear factor-erythroid 2-related factor 2 (NRF2) signaling pathway was activated and the mRNA and protein expression of its downstream targets such as quinine oxidoreductase 1 (NQO1), heme oxygenase-1 (HO-1), glutamate-cysteine ligase catalytic subunit (GCLC) and glutamate cysteine modifier subunit (GCLM) were up-regulated, which alleviated oxidative stress injury. In a summary, this study demonstrate the dynamic change of CPA-induced liver injury and the NRF2-mediated protective mechanisms, providing new insights into the CPA-induced liver injury.
In this paper, a new type of preparation for treatment of initial dry eye disease, thermosensitive in situ gel, was prepared using levocarnitine as a model drug. Poloxamer 407 and poloxamer 188 were used as the gel matrix, and sodium hyaluronate and sodium carboxymethylcellulose were used as bioadhesive materials. Gelation temperature was determined by a rotor method and the prescription was optimized by central composite design-response surface methodology. The pH value, viscosity value and gelation temperature of the optimal prescription were measured. The release of the drug in vitro was examined by dialysis membrane permeation, and retention time of the thermosensitive in situ gel preparation on the rabbit's ocular surface was observed by a slit lamp microscope. The results showed that the dosage of the poloxamer 407 and poloxamer 188 were 20.81% and 3.46%, respectively, and sodium hyaluronate was 0.02%, sodium carboxymethyl cellulose was 0.10% of the optimal formulation of levocarnitine thermosensitive in situ gel. The pH value was 6.90 ±0.06 at room temperature and the viscosity value started to rise sharply at 27℃ of the optimal formulation. The gelation temperature of the optimal preparation before and after dilution by simulated tear fluid were (26.37 ±0.06)℃ and (33.57 ±0.21)℃, respectively. In the first 240 min, in vitro release rate per unit area of levocarnitine thermosensitive in situ gel was lower than that of solution (P < 0.05), and after 600 min, the cumulative release rate of levocarnitine thermosensitive in situ gel could reach more than 80%. The retention time of the thermosensitive in situ gel preparation on rabbit's ocular surface reached about 25 min, at least 5 times as much as that of the solution. The animal experiment was conducted following the National Institutes of Health Guidelines for the use of experimental animals, and approved by the Ethics Committee of the Experimental Animal Center of Beijing University of Chinese Medicine. The levocarnitine thermosensitive in situ gel showed good characteristics and sustained release property and significantly improved the retention time of the drug on the rabbit's ocular surface.
This paper summarizes research progresses of Chinese scholars in the field of drug metabolism and pharmacokinetics (DMPK) in 2018. Chinese scholars focused on drug metabolizing enzymes and transporters, and carried out studies on the mechanisms of drug metabolism and transport of active molecules. Topics of research included regulatory mechanisms of drug metabolizing enzymes or transporters, and their implications in drug development and disease etiology or progression. Here, we summarized studies on drug toxicity based on drug metabolism or transport, rational drug use in the clinic, drug metabolism mediated by intestinal flora, metabolism of traditional Chinese medicines, and new technologies or models in DMPK. In recent years, the research focus of drug metabolism in China has transformed from serving for new drug discovery and rational use, to innovation driven and mechanism oriented research. The domestic research topics and technology utilization are gradually aligning with the international conventions.
Exosomes are membranous vesicles that are actively secreted by cells. They can be isolated from various cell culture media and animal body fluids. Exosomes are mainly composed of lipids, proteins and nucleic acids. They have small molecular structure and high biocompatibility with size of 40-100 nm. In addition, exosomes are natural endogenous nanocarriers that can transport lipids, proteins, DNA and RNA. Studies have shown that exosomes play an important role in long-distance communication between cells, in physiological and pathological processes. This article introduces the composition and physiological functions of exosomes, and summarizes the relevant content of exosomes as drug delivery vehicles. The applications of exosomes in central nervous system diseases, especially brain diseases and tumors are summarized.