Latest ArticlesThe hyperacute stage of myocardial infarction refers to a period of time within 30 minutes after the occurrence of myocardial infarction, when the symptoms are not obvious and the diagnosis is difficult, and the related pathophysiological mechanism has received less attention. In this study, proteomics was used to investigate the pathological changes in the early hyperacute phase of myocardial infarction, aiming to provide experimental evidence for pathological mechanism of myocardial infarction hyperacute stage. Meanwhile, the intervention effect and related mechanism of salvianolate injection were discussed based on heat shock protein B6 (HSPB6), aiming to benefit the clinical rational use of salvianolate injection. The protein expression changes before and after myocardial infarction model establishment were detected by label-free proteomics via mass spectrometry and analyzed by bioinformatics method. Then the binding effect of salvianolate injection on the commonly differential protein HSPB6 was evaluated by molecular docking technology, which was finally verified by animal experiments. All animal experimental protocols were approved by the Ethics Committee of Xiyuan Hosptial (2022XLC041). The results of this study showed that a total of 2 166 proteins were quantified by lable-free proteomics, of which 194 shared differential proteins were involved in myocardial injury and body regulation in the hyperacute phase of myocardial infarction, mainly involving molecular functions such as protein homodimerization activity, oxygen binding and transport, and serine endopeptidase inhibitor activity. Among them, HSPB6 protein is involved in the regulation of myocardial function. Molecular docking results indicated that magnesium salvianolate acetate, which is the main component of salvianolate injection, had the lowest binding energy with HSPB6 protein: -14.53 kcal·mol-1. Animal experiments showed that compared with the Sham group, the model group had significantly lower ejection fraction (EF) and fractional shortening (FS) (P < 0.001), cardiac blood perfusion decreased significantly (P < 0.001). There were obvious pathological changes such as myocardial fiber disorder, cardiomyocyte edema and interstitial small blood vessel congestion; the injury of cardiac function of rats in the administration group was attenuated, and the FS of rats in the low-dose group was significantly improved (P < 0.05), the pathological injury of myocardial tissue was markedly mitigated, and the expression of HSPB6 protein was up-regulated to varying degrees (P < 0.01, P < 0.001). In conclusion, salvianolate injection could be able to improve the cardiac function and pathological morphology of rats in the early hyperacute stage of myocardial infarction, and its mechanism may be related to the promotion of expression of HSPB6.
Two undescribed terpene glycosides and two compounds were isolated from the n-butanol fraction of Alpiniae Oxyphyllae Fructus by using various chromatographic methods, including MCI Gel, Sephadex LH-20, ODS, silica gel and semi-preparative HPLC. The structures of the isolated compounds were identified by spectroscopy methods (1D, 2D NMR, UV, IR, MS, etc.), and the absolute configuration of the compound 1 was determined by ECD calculation and acid hydrolysis. Compounds 1 and 2 are new compound, and compounds 3 and 4 were isolated from Alpiniae Oxyphyllae Fructus for the first time.
Based our previous work, twelve purine derivatives were designed and synthesized as dual modulators of GPR119 and DPP-4by conjugating the GPR119 activating and DPP-4 inhibiting fragments with the position 6 and 9 of purine core via an approach of merged pharmacophores. Compound 11, bearing 2-fluoro-4-methylsulphonyl anilide and cyanopyrrolidine moieties, exhibited the most potent GPR119 agonistic activities (EC50 = 0.33 μmol·L-1, IA = 71.1%) and DPP-4 inhibitory (58.4% inhibition at 10 μmol·L-1, 21.2% inhibition at 1 μmol·L-1) activities in the in vitro antidiabetic study. Subsequently, we performed studies on structure activity relationships and molecular docking to guide the further drug design.
Pneumoconiosis is the most common occupational disease in China, which severely endangers people's health. Depending on the inhaled air pollutants, pneumoconiosis is classified as anthracosis, silicosis, asbestosis, etc., among which silicosis is the most common and serious. Silicosis is a systemic, poor prognostic disease characterized by diffuse fibrosis of lung tissue, which is caused by long-term exposure to dust with high levels of free silicon dioxide (SiO2) in the occupational environment. Appropriate treatment in time is important for the disease. Unfortunately, no effective drugs have been approved to delay or even reverse pulmonary fibrosis caused by SiO2. This review briefly classifies potent therapeutic drugs and compounds in term of mechanisms, providing the probability for clinical treatment of silicosis.
Redirecting immune cells to the tumor cells and enhancing its anti-tumor immune response is a very promising cancer treatment strategy. AS1411 aptamers have high affinity for malignant tumors with high nucleolin expression, and cytotoxic T lymphocyte associated protein 4 (CTLA-4) aptamers can specifically bind to CTLA-4, which is expressed by T cells. In this study, a dual-affinity aptamer targeted liposome (Dat. Lipo) was constructed based on AS1411 aptamer and CTLA-4 aptamer, and its immunotherapeutic effect on T cells was studied. After the aptamer was modified with cholesterol, Dat. Lipo was prepared by instillation method; its effect of redirecting T cells was determined by confocal micrographs; its T cell immunotherapy effect was evaluated by cell counting kit-8 (CCK8) and T cell penetration was evaluated by tumor spheroids. The results showed that compared with liposomes loaded with one type aptamer, Dat. Lipo could effectively promote the redirection of T cells to tumor cells; Dat. Lipo had good biosafety and immunotherapeutic effect on MCF-7 and HepG2 cells in a concentration-dependent manner; Dat. Lipo could also promote T cells to infiltrate into the tumor spheroids and enhance the immunotherapy effect of T cells in different dimensions. In summary, Dat. Lipo can use the high affinity of aptamers to redirect T cells to tumor cells, enhance the effect of immunotherapy, and has a promising application prospect in tumor therapy. This study was approved by the Examination Committee of Cancer Hospital of Xiangya School of Medicine, Central South University, Hunan Cancer Hospital.
The complete chloroplast genome of medicinal plant Asarum caudigerum Hance and its close relative A. cardiophyllum Franchet were sequenced using Illumina Hiseq technology, and assembled, annotated, and characterized by bioinformatic methods in this study. Then phylogenetic analysis of the complete chloroplast genomes of A. caudigerum, A. cardiophyllum, and twelve published species was conducted. The results indicated that the chloroplast genomes ranged from 186 215-186 985 bp in length, with a large single copy (LSC, 89 445-90 169 bp) and two inverted repeats (IRa/IRb, 48 387-48 408 bp). The overall GC content was 37.4%-37.5%. A total of 144 chloroplast genes were annotated, including 98 protein coding genes, 38 tRNA genes and 8 rRNA genes. In addition, complex genomic rearrangements were detected in the chloroplast genome of Asarum. Meanwhile, visual evaluation of the discrete type of the sequence indicated that the variation level of non-coding region was higher than that of coding region. Phylogenetic analyses suggested that A. caudigerum and A. cardiophyllum were clustered into a single clade and A. cardiophyllum, A. sieboldii var. seoulense, A. misandrum and A. maculatum were clustered into another single branch. These two clade were sister species. This study provides a scientific basis for the identification, phylogenetic relationship, molecular breeding of Asarum species.
A BBB co-culture cell model consisting of rat brain microvascular endothelial cells (BMEC) and astrocytes (AS) was established to study the effect of Angelica dahurica coumarins on the transport behavior of puerarin across blood-brain barrier (BBB) in vitro and in vivo. The barrier function of this model was evaluated by measuring the transendothelial resistance, phenol red permeability and BBB related protein expression. The permeability assay and western blot methods were performed to study the effects of Angelica dahurica coumarins on the BBB permeability and the expression of BBB related protein. The animal experiment protocols in this study were approved by the Animal Ethics Committee of Xi'an Jiaotong University (Animal Ethics No.: 2021-1329). The results showed that the established BMEC/AS co-culture model could be used to evaluate drug transport across BBB in vitro. After combined with Angelica dahurica coumarins, the transport capacity of puerarin was significantly increased in vitro and in vivo. Additionally, Angelica dahurica coumarins enhanced BBB permeability and inhibited the protein expression of P-glycoprotein (P-gp), zonula occludens-1 (ZO-1) and occludin. Angelica dahurica coumarins might increase BBB permeability by inhibiting the expression of P-gp and tight junction protein, thereby increasing the content of puerarin in brain tissue.
Human hormones at trace levels play a vital role in the regulation of a variety of functions and systems in the body, and an imbalance in hormone levels can lead to the emergence and development of diverse diseases. Therefore, the development of reliable sample pretreatment methods and sensitive and accurate analytical techniques for human hormone detection could contribute to the prevention, diagnosis and treatment of diseases, providing significant improvement for human health. Human samples which are usually used to detecting hormones, such as blood, saliva, urine and other matrix are more complex, so sample pretreatment is an important step to ensure the accuracy and reliability in the detection of hormones. In this review three common sample pretreatment methods including solid phase extraction (SPE), liquid-liquid extraction (LLE) and protein precipitation (PP) methods are discussed. Then, recent research progress in conventional techniques like liquid/gas chromatography and liquid/gas chromatography-mass spectrometry (LC/GC-MS/MS), as well as some novel strategies, such as immunoassay including chemiluminescence immunoassay (CLIA), lateral-flow immunoassay (LFIA) and time-resolved fluoroimmunoassay (TRFIA), and sensor technology including electrochemical (EC), fluorescent (FL) and surface-enhanced Raman scattering (SERS) sensors, and microfluidic chip analysis are discussed for human hormone detection. Finally, the future perspective on the use of these methods for hormone detection is considered. It is hoped to provide powerful insights to researchers for the relevant researches.
O-methyltransferases (OMTs) are one of the key tailoring enzymes in the biosynthesis of many natural products, O-methylation can not only reduce the reactivity of natural products, but also alter their solubility, stability and biological activities. Based on the transcriptome data of Ardisia japonica, a full-length cDNA sequence of candidate OMT (termed as AjOMT1) was cloned by reverse transcription-polymerase chain reaction (RT-PCR) and expressed in Escherichia coli (E. coli) for the first time. In vitro enzyme catalytic activity assay showed that the recombinant AjOMT1 could effectively catalyze quercetin to form O-methylated products. Most importantly, AjOMT1 showed unprecedented substrate promiscuity towards structurally various compounds including flavonoids, stilbenes, coumarins, alkaloids and phenylpropanoids, especially preferring to the compounds with adjacent phenolic hydroxyl groups, and showed regio-selectivity. These results suggested that AjOMT1 could be used as the tool enzyme to conduct O-methylation of different types of compounds to produce diverse active methylated products, and provide a new method for drug discovery, even universal part for synthetic biology of natural products.
Tuberculosis (TB), an infectious disease caused by Mycobacterium tuberculosis (Mtb), is still one of the significant threats to human life. In recent years, the continuous exploration of small molecule inhibitors represented by bedaquinoline has brought new vitality into the field of tuberculosis. However, small molecule inhibitors will inevitably occur acquired drug resistance during clinical medication. As a new pharmacological mechanism, targeted protein degradation (TPD) achieves efficacy by destroying rather than inhibiting protein targets. It might be an excellent strategy to develop anti-tuberculosis drugs based on the TPD concept to solve drug resistance. This article reviews the protein degradation pathways of Mtb, such as the Pup proteasome system and the ClpP-ClpC1 complex enzyme system. The future development of these strategies into TPD drugs was prospected and summarized.