Latest ArticlesThe New Delhi metallo-β-lactamase-1 (NDM-1) was first reported in 2010, detected in a Klebsiella pneumoniae isolate from a Swedish patient of Indian origin. It has recently attracted extensive attention for its biological activities to catalyze the hydrolysis of almost all of β-lactam antibiotics. The gene for NDM-1 can spread from one strain of bacteria to another by horizontal gene transfer. The most troubling aspect is that there are currently no clinically available inhibitors to block the metallo-β-lactamase action. Therefore, there is urgent need to develop new NDM-1 inhibitors, which can protect β-lactam antibiotics from the hydrolysis effect of NDM-1. In this review, the current research, drug-assistant mechanism and potential NDM-1 inhibitors are summarized.
An LC-MS/MS method was developed for the simultaneous determination of fosaprepitant and aprepitant in human plasma, and applied to a pharmacokinetic study of 150 mg fosaprepitant dimeglumine injection to 12 Chinese healthy volunteers. The analytes and internal standards were extracted from plasma by protein precipitation with acetonitrile and separated on a Cortex C18+ (50 mm×2.1 mm, 2.7 μm) column using a gradient elution procedure. Mass spectrometry was performed in negative MRM mode, and parent-to-produce transitions were as follows:m/z 613.1→78.9 for fosaprepitant, m/z 617.0→78.9 for d4-fosaprepitant, m/z 533.2→275.1 for aprepitant and m/z 537.2→279.1 for d4-aprepitant. Plasma sample was basified to stabilize fosaprepitant. The standard curves were demonstrated to be liner in the range of 15.0 to 6 000 ng·mL-1 for fosaprepitant and 10.0 to 4 000 ng·mL-1 for aprepitant. The intra-day precisions and inter-day precisions and accuracy were within the acceptable limits for all concentrations.
Safflower is a dried flower of the annual herbaceous plant safflower (Carthamus tinctorius L.). As a traditional Chinese medicine, it was widely used in the regulation of blood circulation. Flavonoids are the main active ingredients in safflower. MYB transcription factors are involved in the regulation of flavonoids. The cloning and expression analysis of MYB transcription factor genes in safflower is of great significance, not only for clarifying the regulation mechanism of flavonoids biosynthesis in safflower, but also for the artificial regulation of flavonoid biosynthesis in safflower. Based on the transcriptome data, we used iTAK to annotate the MYB transcription factors in safflower. The MYB transcription factors were cloned and their sequences were analyzed. Besides, their expressions were analyzed by a Real-time PCR. In the experiment, eight long fragment MYB transcription factors were screened and six MYB transcription factors was successfully cloned, named CtMYB-TF1, CtMYB-TF2, CtMYB-TF4, CtMYB-TF5, CtMYB-TF6 and CtMYB-TF7, respectively. The six MYB transcription factors had the core domain of MYB transcription factor family, and evolutionary analysis showed that the CtMYB-TF7 transcription factor was closely related to the factors AtMYBL2 and AtMYB12. Expression analysis showed that the expression of CtMYB-TF5, CtMYB-TF6 and CtMYB-TF7 was low in roots, stems and leaves, and was high in the flower. The results provide a foundation for study of mechanism of molecular regulation of safflower flavonoids.
This study was to investigate the effect of RORα activator SR1078 on ovarian cancer cells and its molecular mechanism in vitro. The survival rate of HeyA8 and Hey cells was detected by MTS assay; the apoptosis and cells cycle distribution after SR1078 treatment and the effect of p53 siRNA or PFT-α and PFT-β of p53 inhibitors on SR1078-induced apoptosis of HeyA8 or Hey cells were analyzed by flow cytometry. Western blot was used to detect the effect of SR1078 and p53 siRNA on the expression of p53 protein and the effect of p53 inhibitors alone or in combination with SR1078 on the expression of p53, p-p53 and its downstream pro-apoptotic protein Noxa. The results showed that SR1078 significantly reduced the cell viability and induced apoptosis in HeyA8 and Hey cells. In addition, SR1078 up-regulated the protein expression of p53 and Noxa, and p53 suppression led to significant inhibition of SR1078-induced apoptosis and the expression of Noxa in ovarian cancer cells. In summary, SR1078 induced apoptosis of ovarian cancer cells by activation of p53 signaling pathway.
Proteolysis-targeting chimeras (PROTACs) are small-molecule protein degraders based on the ubiquitin-proteasome system. Recently, the development of specific small-molecule ligands for several E3 ligases (CRL4CRBN, CRL2VHL and cIAP) have significantly advanced the PROTACs technology. Several PROTACs against various oncogenic proteins including bromodomain-containing protein 4 (BRD4), estrogen receptor (ER) and androgen receptor (AR) have been developed and considered a novel approach for therapy of cancers. There are advantages of the new technology over the traditional small-molecule strategies. This review article provides a summary on the recent progress in the small-molecule-based PROTACs as antitumor drugs, and the challenges of this technology.
In this study, we used low molecular weight heparin (LH) as hydrophilic sides, doxorubicin (DOX) as hydrophobic sides, and indocyanine green (ICG) as a photosensitive drug to prepare pH-sensitive self-assembled polymeric micelles (LH-DOX/ICG). The micelles were prepared by dialysis, and evaluated for stability, pH sensibility in vitro, hemolytic test and photo-thermal effect. Wound healing test was used to evaluate the anti-metastatic effects. MTT assay and apoptosis detection kit were used to evaluate the cytotoxicity of micelles against melanoma B16F10 cells. The size of the micelles was (148.7 ±2.1) nm and the zeta potential was (-30.7 ±1.1) mV. The drug-loading content of DOX and ICG were 11.82% and 5.59%, respectively. The micelles exhibited spherical in shape, fairly uniform size. The micelles were stable within 48 h in 50% fetal bovine serum phosphate buffer. The release of DOX was pH-sensitive, while the release of ICG was sustained. The micelles were biocompatible and safe as indicated by the hemolytic test. In vitro photo-thermal effect indicated LH-DOX/ICG micelles had similar photo-thermal effect to the free ICG. Wound healing test showed that the micelles had a good ability to inhibit tumor migration with laser irradiation. MTT assay and cell apoptosis assay indicated that LH-DOX/ICG micelles displayed more efficient anti-tumor effect after near infrared laser compared to LH-DOX micelles. LH-DOX/ICG micelles are promising for the therapeutic effect of phototherapy and chemotherapy in combination for melanoma.
Depression is a complex heterogeneous psychiatric disorder with a potential to cause patient disability worldwide. In the past decades, a number of the first-line drugs (tricyclics, monoamine oxidase inhibitors, serotonin selective reuptake inhibitors, noradrenaline reuptake inhibitors, serotonin and noradrenaline reuptake inhibitors, etc.) had been discovered for the treatment of depression. CYP450 superfamily is involved in the biotransformation of antidepressants mainly through the CYP2D6, CYP2C19, CYP3A4 isoenzymes. Their genetic polymorphisms are closely related to clinical use and the interactions have been already identified between enzymes and antidepressants. This review focuses on drug metabolism and the interaction for CYP450 enzymes. The content may contribute to the development of antidepressant, improvement of the safety of antidepressants and the efficacy of treatment.
This study was designed to investigate the effect of Yinxing Mihuan oral solution on rats with myocardial ischemia injury. Left anterior descending (LAD) coronary artery was occluded in rats to establish the model. Yinxing Mihuan oral solution was given by intragastric administration daily for one week at dosage of 309 and 618 mg·kg-1. Cardiac ultrasound function, pathologic change and serum myocardial enzymes were determined to evaluate the effect of Yinxing Mihuan oral solution. The heart function was significantly reduced in the model group compared with sham operation group, and the pathologic damage was clear. The changes were significantly improved by Diltiazem hydrochloride tablets in heart function and ejection fraction (P < 0.01). The ejection fraction and stroke volume was improved by Yinxing Mihuan oral solution (618 mg·kg-1) (P < 0.05, P < 0.01). In addition, Yinxing Mihuan oral solution decreased the myocardial damage and inhibited inflammatory reaction, and inhibited platelet activation factor. Yinxing Mihuan oral solution can protect against myocardial ischemia injury, inflammation and platelet activation in the rat model.
This study was conducted to establish an in vitro 3D liver model and apply it to the drug liver toxicity evaluation. The 3D multicellular sphere model of HepaRG cells was established by hanging-drop technique for evaluation of liver function. The 3D liver model was used to test the hepatotoxicity of isoniazid and amiodarone hydrochloride compared to the 2D cell culture model. Our results showed that HepaRG cells formed a compact spheriod, and the level of cell albumin, urea and the CYP3A4 activity were significantly higher than that of 2D model. With the treatment of amiodarone hydrochloride in 2D and 3D model, the IC50 were 50 and 100 μmol·L-1, respectively. When the dose was less than 1 000 μmol·L-1, isoniazid had no hepatocyte toxicity in 2D model, while the IC50 in 3D model was 700 μmol·L-1. The LDH activities of both drugs in 3D model showed time-and dose-dependent correlation. The results suggest that this in vitro 3D hanging-drop liver model is good for testing liver functions with a high hepatic drug-metabolizing enzyme activity. Compared with the 2D model, the 3D liver model can accurately evaluate the liver toxicity of drugs. Our results demonstrated the importance of in vitro cell culture models for detection of in vivo-relevant adverse effects of drugs.
Calcium signaling plays a critical role in response to various abiotic and biotic stresses in plants. Preliminarily evidence showed that calcium signaling perceived and transduced the harmful signaling generated from continuous cropping stress in R. glutinosa. To investigate the roles of calcium signaling in continuous cropping injury formation, the key genes involved in calcium signaling transduction were identified in R. glutinosa transcriptome through bioinformatic methods. Furthermore, the calcium ion concentration in both normal and continuous cropping R. glutinosa root cells were measured by potassium pyroantimonate precipitation and calcium fluorescence method. As a result, a set of 84 calcium signaling-related genes, including 5 CaMs, 12 CBLs, 21 CDPKs, 21 CIPKs, 16 CMLs, and 9 CRKs were captured in R. glutinosa transcriptome. The analysis of expression profile in continuous cropping compared to normal growth R. glutinosa indicated that continuous cropping stress significantly increased the expression of calcium signaling-related genes in continuous cropping R. glutinosa. At the same time, the abundance levels of 12 calcium signaling-related genes quantified by qPCR further validated the high expression of calcium signaling-related genes presented in continous cropping R. glutinosa. In addition, the continuous cropping condition significantly promoted the accumulation of intracellular calcium ions in R. glutinosa based on two methods of potassium pyroantimonate precipitation and calcium fluorescence. This study verified the possible roles of calcium signaling in the formation of continuous cropping injury on molecular and cellular level, which lays a solid foundation for illuminating formation mechanism of continuous cropping injury on molecular level.