Latest ArticlesTuberculosis (TB) caused by Mycobacterium tuberculosis (M. tuberculosis) infection remains a major public health problem of global concern, largely due to antibiotics resistance, persistence and immune evasion. Sphingolipid bioactive molecules are involved in several important pathophysiological processes. Sphingosine-1-phosphate is a key product of sphingolipid metabolism, and can play a role in two manners:autocrine and/or paracrine. Sphingosine-1-phosphate regulates T cells and a variety of antigen-presenting cells during M. tuberculosis infection, promotes antigen processing and expression in monocytes, is involved in the maturation of phagolysosome, regulates Ca2+ homeostasis, participates in the autophagy of macrophages, inhibits the survival and proliferation of M. tuberculosis within host cells, and effectively reduces the necrosis of the mouse lungs infected by M. tuberculosis. Injection of 20 nmol per mouse sphingosine-1-phosphate inhibited up to 47% of mycobacterial growth in the lung and spleen of mice infected by M. tuberculosis. In this paper, sphingosine-1-phosphate, its receptors and regulatory network were reviewed, and the specific mechanism of sphingosine-1-phosphate inhibiting the survival of M. tuberculosis-infected host cells was elaborated. This will provide novel insights into the new targets for tuberculosis prevention and treatment.
Diabetic kidney disease (DKD) is one of the most serious microvascular complications in diabetic patients, and is the leading cause of end-stage renal disease. The interaction between metabolic and hemodynamic factors leads to activation of the common pathways of diabetic kidney injury. Studies have shown that salvianolic acid can alleviate renal fibrosis and renal injury caused by diabetes by regulating renal tubular interstitial activator A, transforming growth factor-β1 and monocyte chemokine protein-1. It can also participate in the reconstruction of the glomerular extracellular matrix by affecting the expression of protein kinase ERK1/2 protein, which serves a protective effect on diabetic kidneys. Tanshinone can inhibit oxidative stress mediated glucose-induced kidney injury, inhibit the expression of protein tyrosine phosphatase 1B (PTP1B) activity, and improve the secretion function of beta cells in type 2 diabetes mellitus. Interstitial fibrosis in diabetic nephropathy can be alleviated by blocking TGF-β/Smad, NF-κB and Wnt/β-catenin signaling pathway. It has been suggested that salvianolic acid and salvianone are excellent candidates for prevention and treatment of diabetic nephropathy. We provide here the scientific basis for in-depth research and development of salvianolic acid and salvianone into drugs.
Utilization of traditional Chinese medicine (TCM) resources for pharmaceutical development is an important part of modernization of TCM. The classical TCM prescriptions provide an important insight for developing new drugs. Based on the advantages of local TCM resources, focusing on the key scientific problems in the quality evaluation of medicinal materials and the study of classical prescriptions, this research group takes the quality evaluation of medicinal materials as the starting point. Metabolomics serves as a technical means of "quality evaluation of TCM, to support scientific connotation of classical prescriptions and development of new drugs from TCM. Using Radix Bupleurum as an example, this paper systematically and thoroughly expounds the above research ideas and strategies from the aspects:quality evaluation of medicinal materials, basic research of Xiaoyansan, and research and development of new anti-depressants. This provides the scientific basis for the modernization of TCM.
6-Bromo-3-n-butylphthalide was obtained by nitration, reduction and diazotization from carboxybenzaldehyde. Twenty hybrids from substituted styrene and 6-bromo-3-n-butylphthalide were synthesized and the structure was confirmed by 1H NMR, 13C NMR and ESI-MS. All compounds were evaluated for neuroprotective activity against OGD/R-induced neurotoxicity in rat cortical neurons by MTT assay. The mechanism of neuroprotection was investigated by Western blot analyses. The results indicated that most of these compounds had a potent neuroprotective activity (All animal experiments were approved by the Experimental Animal Ethics Committee of Anhui University of Chinese Medicine), especially 10h and 10i showed significant effects, which may play a neuroprotective role by activating the PI3K/Akt signaling pathway.
This research is aimed to investigate the effect of ampelopsin on apoptosis and migration of human hepatoma SMMC-7721 cells and explore the molecular mechanism. SMMC-7721 cells were pretreated with different doses of ampelopsin and cells proliferation was detected by CCK8 kit. Cell morphology was observed under an inverted microscope. Nuclear morphology was detected by DAPI staining. Apoptotic rate was detected by Annexin V-FITC/PI flow cytometry. Migration and invasion were detected by Transwell and scratch healing test. Western blotting was used to detect cleavage of poly ADP-ribose polymerase (PARP), expression of matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9), E-cadherin, and N-cadherin, and phosphorylation of ERK, P38 and JNK in MAPKs pathway. Our results showed that ampelopsin significantly inhibited proliferation and induced apoptosis of SMMC-7721 cells, with half inhibition dose (IC50) for 24 h was 38.98 μg·mL-1. With 50 μg·mL-1 ampelopsin treatment, typical apoptotic morphological changes occurred, such as cell detachment, shrinkage and nuclear condensation. Apoptotic rate increased from 15% to 55.1%, with PARP cleavage significantly increased. In addition, treatment of ampelopsin reduced scratch healing of cells and transmembrane cells number. The expression levels of MMP-2 and MMP-9 were decreased. Further analysis of EMT-related proteins showed that after ampelopsin treatment, E-cadherin was up-regulated and N-cadherin was down-regulated. During ampelopsin treatment, ERK reached its peak of activation after 1 h, while the maximum activation time of JNK was 12 h. Meanwhile, P38 was activated within 4 h, with the highest point at 2 h. But after 4 h, ampelopsin inhibited phosphorylation of P38. These results indicated that ampelopsin induced apoptosis and reduced migration through activating MAPKs pathway and reversing EMT process in SMMC-7721 cells. This work provides a mechanistic basis for utilizing ampelopsin for anti-hepatocarcinoma treatment.
UDP-rhamnose is a rhamnose donor in a reaction catalyzed by UDP-rhamnose synthase (RHM), and plays an important role in the biosynthesis of rhamnoside compounds. The current literature suggests that there are only a few genes can encode the corresponding enzymes to participate in UDP-rhamnose biosynthesis in plants. In this study, two RHM genes (FmRHM1 & 2) were first cloned by using the transcriptomic data of Fallopia multiflora (Thunb) Harald and the multidimensional analysis, including bioinformatics, functional identification in vitro and tissue-specific expression analysis. The results showed that the open reading frame (ORF) of FmRHM1 & 2 genes both were 2 013 bp, encode proteins consisting of 670 amino acids with a calculated molecular mass of 75.6 kDa, and the theoretical isoelectric points of 6.20 and 7.19, respectively. Bioinformatic analysis also indicated that FmRHM1 & 2 contained 2 special sequences of GxxGxxG/A and YxxxK. The phylogenetic analysis showed that the FmRHM gene has a high homology with RHM of other species. The results of enzyme activity in vitro revealed that both recombinant FmRHM1 and FmRHM2 have catalytic activities for converting UDP-glucose into UDP-rhamnose. Measurements of tissue-specific expressions showed that the expression levels of FmRHM1 and FmRHM2 were lower in roots. On the contrary, the 2 genes showed significantly high expression in the stems and leaves. In conclusion, we have cloned and characterized the RHM gene function for the first time in F. multiflora. Here we have provided the preliminary data suggesting the need for further research on UDP-rhamnose biosynthesis by microorganisms.
The chemical constituents of Viburnum taitoense Hayata were investigated using column chromatography silica gel and Sephadex LH-20, etc. Seven pentacyclic triterpenoids were isolated and their structures were elucidated by spectral data and physicochemical properties as 3β, 6β-dihydroxy olean-11, 13(18)-dien-28-acid (1), 3β-hydroxy olean-11, 13(18)-diene-28-acid (2), 12-ene-olean-28-acid-3β-palmitate (3), 3β-acetylcocodiol (4), corosolic acid (5), uvaol (6) and ursolic acid (7). Among them, compound 1 is a new oleanane type triterpenoid and its absolute configuration was confirmed by single-crystal X-ray diffraction data. Compounds 2-5 were isolated from this genus for the first time. All the compounds were evaluated for their anti-inflammatory activities in vitro, and compound 5 showed significant inhibitory activity against nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 macrophage cells with an IC50 of 25.52 ±0.56 μmol·L-1 when compared to the positive control, quercetin (IC50 of 25.46 ±0.62 μmol·L-1).
Immunotherapy is the most active research area for cancer treatment. Tumor vaccine is one of the most developed aspects of cancer immunotherapy. Though tumor vaccine has made many breakthrough, it still faces many challenges. In this study, we coated the black phosphorus quantum dots (BPQDs) with cancer cell membrane to create a nanoparticle named BPQD-CCNVs. The BPQD-CCNVs were incubated with bone marrow-derived dendritic cells and irradiated with 808 nm infrared light. We tested the expression level of CD80, CD86 and MHC Ⅱ of dendritic cells by flow cytometry after irradiation. All animal experiments approved by the Animal Experiments Ethical Committee of Tsinghua University. The results showed that the rise of medium's temperature caused by the photothermal effect of BPQDs could upregulate the expression of CD80, CD86 and MHC-Ⅱ on dendritic cell surface. Based on these, we conclude that near infrared irradiation can stimulate the activation of dendritic cells. Our study may have provided a new strategy for tumor vaccine development.
To ensure the consistency of quality in recombinant protein production, the cell bank for biologics should be derived from a single clone. A number of techniques have been used for cloning and assurance from the cellular pool after transfection with a target gene. Here, using CHO cell as an example, we summarize the knowledge and understanding of monoclonality of production cell bank from both industries and regulatory authorities, and propose general considerations on the requirements of monoclonality for clinical trial application and new drug application based on current techniques. Furthermore, we suggest quality control strategies and assessment methods for those cell banks from non-single clones.
Foxo-1 plays an important role in development of muscle atrophy, serving as a potential target for therapeutic treatment of the disease. In this study, the Foxo-1 mRNA was targeted by a Foxo-1 specific RNA oligonucleotide modified by 2'-O-methyl and with a butanol tag at the 3'-end. To understand the in vivo significance of new modified RNA oligos, efficacy, pharmacokinetic and safety profiles of the new modified RNA oligonucleotide targeting Foxo-1 were evaluated in mice. All experimental protocols were approved by the Animal Ethics Committee of Institute for Nutrition and Health, Chinese Center for Disease Control and Prevention. The results showed that different doses of the RNA oligonucleotide can reduce the expression of Foxo-1 in mice by two routes of administration, leading to an increase in skeletal muscle mass of the mice. The results of pharmacokinetic evaluation showed that the plasma disappearance curve for the RNA oligonucleotide could be described by a two-compartmental model. The results of safety evaluation showed that no obvious adverse effects on renal and hepatic functions, nor on hematological parameters by intravenous or oral administration of the RNA oligo with a maximum dose of 30 mg·kg-1. Histopathology also did not reveal any significant changes in the morphology of the organs studied. In conclusion, the new modified RNA oligo is safe and effective in mice, providing experimental evidence supporting the significance for its clinical application.