Latest ArticlesThe protective effects of cyclosporin A (CsA), an inhibitor of mitochondrial permeability transition pore (MPTP), on vascular permeability in sepsis rats were investigated. Cecal ligation and puncture (CLP)-induced sepsis rats were used for in vivo studies, and the effects of CsA (1 and 5 mg·kg-1) on vascular permeability of lung, kidney, and intestine, mitochondrial respiratory control ratio, and the survival of the sepsis rats were observed. Lipopolysaccharide (LPS) was used for stimulating vascular endothelial cells (VECs) in vitro, and the effects of CsA on leakage of microvascular, immunofluorescence of zonula occludes-1 (ZO-1), and transendothelial electrical resistance (TER) were observed. All the animal welfare and experimental procedures are in accordance with the regulations of the Animal Ethics Committee of the Army Medical University. Compared with sham-operated group, the vascular permeability of lung, kidney, and intestine in sepsis rats increased significantly (P < 0.05). Compared with conventional treatment group, CsA could significantly decrease the vascular permeability of lung, kidney, and intestine (P < 0.05 or P < 0.01), and prolong the survival period. The results of microcirculation also showed that CsA could significantly reduce the permeability of mesenteric venules in sepsis rats. At the cellular level, LPS stimulation significantly increased the permeability of vascular endothelial cells, including the decrease of transmembrane resistance and protein expression of ZO-1 (P < 0.05). CsA can significantly reduce the increase of permeability of vascular endothelial cells induced by LPS stimulation (P < 0.01). The function of mitochondria in the kidneys and intestines of sepsis rats was obviously impaired, and the respiratory control ratio of mitochondria was decreased. LPS significantly increased MPTP opening of VECs, while CsA significantly inhibited MPTP opening and improved mitochondrial function. CsA may protect mitochondrial function by inhibiting the opening of MPTP and play a protective role in the vascular permeability of sepsis rats. This study will provide an insight for the treatment of sepsis vascular leakage.
Network pharmacology and bioinformatics technology were used to predict the mechanism of action of Fuzi-Lizhong pill (FLP) in the treatment of ulcerative colitis (UC). 26 components (23 prototype compounds and 3 metabolites) in the blood of FLP were selected as the research objects. PharmMapper database, SwissTargetPrediction platform, GeneCards and OMIM database were used to screen and predict potential targets of FLP in blood. The protein-protein interaction network model was constructed by using String database and Cytoscape software. DAVID platform, KEGG and Reactome databases were used for GO analysis and pathway analysis of potential targets. Network of drug ingredients-targets-pathways was constructed by Cytoscape software. AutoDock vina software was used to dock the molecules of the absorbed ingredients of FLP in blood with the key targets. 82 potential targets of FLP for treatment of UC were obtained. Potential targets mainly involve biological processes such as response to organic substance, regulation of apoptosis, regulation of programmed cell death, which played roles in the treatment of UC by adjusting pathways in cancer, Colorectal cancer, Vascular endothelial growth factor signaling pathway, Mitogen-activated protein kinase signaling pathway, arachidonic acid metabolism and the other signal pathways. From the perspective of network pharmacology, this study predicted the mechanisms of action of FLP in treating UC, indicating that FLP in treating UC had the characteristics of multiple ingredients, multiple targets and multiple pathways, which laid a foundation for further research.
Protein arginine methyltransferase 5 (PRMT5) is an important type Ⅱ human methyltransferase. It catalyzes the symmetrical double-methylation of many histones and non-histones, and it is highly expressed in many kinds of tumors. PRMT5 has been proven to be a potential new target for cancer treatment. Based on the reported crystal complex of EPZ015666 with PRMT5, a series of new compounds was designed using GSK3326595 (EPZ015938) as the lead compound and using the conformational restriction approach. We found that compounds B8 and the C series of derivatives displayed enzyme inhibitory activity comparable to that of GSK3326595. Compounds C3 and C4 showed poor permeability in Caco-2 cells, and that might be one of the reasons for their poor anti-proliferative activity against Z-138 cells. These data provide insights for further structural optimization.
This research investigated the mechanism by which bupivacaine inhibits glutamate-induced intracellular free Ca2+ increases in primary cultured hippocampal astrocytes. Immunofluorescence was used to demonstrate the expression of metabotropic glutamate receptor (mGluR5 receptor) on neurons and astrocytes. Calcium imaging was used to measure the alteration of intracellular free Ca2+ ([Ca2+]i) in primary cultured rat hippocampal neurons and astrocytes. The animal experiments were approved by the Animal Experiments Ethical Committee of Hebei Medical University. The results showed that mGluR5 receptor was abundantly expressed in the primary cultured rat neurons and astrocytes. Bupivacaine (300 μmol·L-1) significantly inhibited 1 mmol·L-1 glutamate-induced[Ca2+]i increase in astrocytes (P < 0.01). 2-Methyl-6-(2-phenylethynyl)-pyridine (MPEP) (10 μmol·L-1) completely abolished the increase of[Ca2+]i induced by 1 mmol·L-1 glutamate in the astrocytes (P < 0.01), while the inhibitory effect on neurons was only 10%-20%. Bupivacaine (300 μmol·L-1) completely inhibited the[Ca2+]i increase induced by mGluR5 receptor agonists (RS)-3, 5-dihydroxyphenylglycine (DHPG) (50 μmol·L-1) and (RS)-2-chloro-5-hydroxyphenylglycine sodium salt (CHPG) (1 mmol·L-1) in astrocytes (P < 0.01). In addition, bupivacaine inhibited the CHPG-induced[Ca2+]i increase in a dose-dependent manner in astrocytes with an IC50 of 100 μmol·L-1. The results from this study indicate that bupivacaine inhibits glutamate-induced[Ca2+]i elevation by acting on the mGluR5 receptor in primary cultured hippocampal astrocytes.
Natural products have been a major source of leading compounds in drug discovery. How to effectively screen active compounds from complex matrix remains an interesting topic. In this review, we comprehensively summarized advanced liquid chromatography based approaches in natural products screening, including pre-column, on-column and post-column screening methods. Their advantages, disadvantages and prospect are also discussed.
The chemical constituents of gorgonian Junceella fragilis Ridley, collected from Ximao Island, the South China Sea, were investigated. A new briarane-type diterpenoid, named fragilide Y (1), together with five known compounds (2-6), namely fragilide D (2), cholesterol (3), ergosterol peroxide (4), 2'-deoxythymidine (5) and cis-thyminenol (6), were isolated from the acetone extract of J. fragilis. The structure of the new compound 1 was elucidated by extensive spectroscopic analysis, while the known compounds were identified by comparison with the reported data. In bioassay, none of these compounds displayed obvious anti-inflammatory and cytotoxic effects.
Obesity is an important cause of a panel of metabolic diseases, such as hypertension, hyperlipidemia, arteriosclerosis, type 2 diabetes and various cancers. Discovery of anti-obesity agents has always been a hot spot in the field of new drug research and development. Pancreatic lipase (PL, also named triacylglycerol acyl hydrolase), a key enzyme responsible for the hydrolysis of 50%-70% dietary fats in the gastrointestinal system, which has been recognized as a crucial target for the prevention and treatment of obesity. PL inhibitors can reduce the decomposition and absorption of dietary fat in the digestive organs by decreasing the hydrolytic activity of this key enzyme, which can alleviate the symptoms of metabolic diseases such as obesity and hyperlipidemia. Although a potent PL inhibitor (orlistat) has been marketed, it may trigger gastrointestinal side effects after long-term use. Therefore, it is necessary to develop more new PL inhibitors with strong inhibition potency and safety. In recent years, a large number of studies have found that some Chinese herbal extracts and their constituents can regulate lipid metabolism and treat obesity via inhibiting PL. In this paper, the research progress in the field pancreatic lipase inhibitors, as well as the extracts of Chinese herbs and their constituents with pancreatic lipase inhibitory effects were summarized. Meanwhile, the PL inhibition activities and inhibitory mechanisms of herbal constitutes were also summarized systematically. In addition, the authors also highlight the challenges in this field and the future research directions. All information and knowledge presented in this review will be very helpful for the medicinal chemists to find more potent PL inhibitors from herbs or to develop next generation anti-obesity drugs, as well as helpful for the prevention and treatment of obesity and other related metabolic diseases using herba medicines or related products.
Shiraia bambusiccola is an important medicinal fungus in China. Hypocrellins with perylenequinone skeleton are main bioactive components of Shiraia bambusiccola, which are widely used in food, medicine, pesticide and other fields as natural photosensitizers. For example, "hypocrellin ointment" has already been used clinically. As a rare and vulnerable species, wild Shiraia bambusiccola resources are very limited. Due to the complex structure and chanllenge in chemical total synthesis of hypocrellins, it is urgent to find an effective strategy to rationally utilize its medicinal value while protecting the wild resources. In this study, a candidate gene cluster hpc was identified in Shiraia sp. cfcc 84681 based on careful bioinformatic analysis. A heterologous expression system for hpc gene cluster was successfully constructed and a mutant strain with high yield of hypocrellins was obtained, which mainly produced hypocrellin A and isohypocrellin A. The main ingredients in the mutant strain are consistent with that in the wild Shiraia bambusiccola. These results provide a new strategy to solve the shortage of wild Shiraia bambusiccola resources.
The near-infrared-Ⅱb (NIR-Ⅱb, 1 500-1 700 nm) window fluorescence with long emission wavelength has reduced light scattering and tissue auto-fluorescent background, achieving deep tissue imaging with high spatial resolution. Herein, we prepared an NIR-Ⅱb fluorescent quantum dots (QDs) composed of lead sulfide (PbS). The fluorescence spectrum of PbS QDs were adjusted by controlling the size of the PbS core. Cadmium sulfide (CdS) shell was synthesized by the cation exchange method to form the core/shelled lead sulfide/cadmium sulfide quantum dots (CSQDs). The surface of CSQDs was modified with polyethylene glycol (PEG) to increase their stability in aqueous solution. The resulting PEG-modified CSQDs (PEG-CSQDs) had the emission peak at ~1 550 nm with quantum yield of 7.2%. The animal procedures were approved by the Institutional Animal Care and Use Committee (IACUC) of Fudan University School of Pharmacy. At 2 h postinjection, PEG-CSQDs clearly delineated the tumor region of mice bearing orthotopic CT26-Luc colon cancer model in the NIR-Ⅱb fluorescence imaging. The fluorescent intensity ratio of primary tumor and adjacent normal tissue was 42.3, and that of metastatic tumor and adjacent normal tissue was 22.3, which allowed to detect the primary tumor of 3.4 mm×2.5 mm in dimension and the metastatic tumor of 1.2 mm×0.9 mm in dimension, and accurately guided the excision of tumors. The PEG-CSQDs prepared in this study provided a new approach for the early diagnosis and guidance of surgical resection of colon cancer.
This paper aimed to investigate the release efficiency of peptide at carbon terminal triggered by tetrazine bioorthogonal click-to-release reaction, and further explored the potential application of this reaction in functional modification and mild cleavage in solid-phase peptide synthesis. Thirteen peptide derivatives modified by trans-cyclooctene (TCO) were designed and synthesized, which were reacted with tetrazine to release the peptides. The results showed that the release rates of peptide were 90.0% to 97.7% in one hour. The strategy has good compatibility with the functional side-groups and the length of peptides, which expands the applications scope of tetrazine bioorthogonal click-to-release reaction. At the same time, a novel bifunctional trans-cyclooctene molecule was designed and synthesized. The active peptide GIRLRG was modified by fluorophore on the solid-phase resin, and released through tetrazine click-to-release reaction under mild condition, providing a new strategy for the solid-phase modification and release strategy of the peptide.