Search

Background: Meropenem is a carbapenem antibiotic and is commonly used with other antibiotics for the treatment of bacterial infections. It is primarily eliminated renally by glomerular filtration and renal tubular secretion., Objective: This study aimed to evaluate the roles of renal uptake and efflux transporters in the excretion of meropenem and potential drug interactions mediated by renal drug transporters., Methods: Uptake and inhibition studies were conducted in human embryonic kidney 293 cells stably transfected with Organic Anion Transporter (OAT) 1, OAT3, Multidrug and Toxin Extrusion Protein (MATE) 1, and MATE2K, as well as membrane vesicles containing breast cancer resistance-related protein (BCRP), multidrug resistance protein 1 (MDR1), and Multidrug Resistance-associated Protein 2 (MRP2). Probenecid and piperacillin were used to assess potential drug interactions with meropenem in rats., Results: We observed that meropenem was a low-affinity substrate of OAT1/3 and had a weak inhibitory effect on OAT1/3 and MATE2K. BCRP, MDR1, MRP2, MATE1, and MATE2K could not mediate renal excretion of meropenem. Moreover, meropenem was not an inhibitor of BCRP, MDR1, MRP2, or MATE1. Among five tested antibiotics, moderate inhibition on OAT3-mediated meropenem uptake was observed for linezolid (IC 50 value was 69.2 μM), weak inhibition was observed for piperacillin, benzylpenicillin, and tazobactam (IC 50 values were 282.2, 308.0 and 668.1 μM, respectively), and no inhibition was observed for sulbactam. Although piperacillin had a relatively high drug-drug interaction index (ratio of maximal unbound plasma concentration to IC 50 was 1.42) in vitro, no meaningful impact was reported on the pharmacokinetics of meropenem in rats., Conclusion: Our results indicated that clinically significant interactions between meropenem and these five antibiotics are low., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Anti-vascular endothelial growth factor (anti-VEGF) therapy is effective for reducing the severity level of diabetic retinopathy (DR). However, it is difficult to determine the in vivo spatial and temporal expression of VEGF in the DR retina at an early stage. Here, we report a quantitatively fluorescence molecular imaging and image analysis method by creating a VEGF targeted fluorescence imaging probe, which can potentially detect and predict anti-VEGF treatment response. Moreover, the ex vivo multiscale fluorescence imaging demonstrated the spatial correlation between VEGF relative expression and vascular abnormalities in two and three dimensions. It revealed that VEGF was mainly abnormally expressed at the bifurcation of the microvessels, which advances the knowledge of the DR progression by molecular fluorescence imaging. Our study has the potential to achieve early detection of DR disease, provide more insight into understanding anti-VEGF treatment, and may help stratify patients based on the molecular imaging of retinal VEGF., Competing Interests: The authors declare no conflicts of interest., (© 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement.)

Asthma is one of the most common pulmonary diseases that threatens human life because of lack of effective medicines. Protostemonine (PSN), an active alkaloid extracted from the roots of Stemona sesslifolia, has anti-inflammatory effects on acute lung injury and acute liver failure. However, it has not been defined whether PSN alleviates asthmatic inflammation. Here, we reported that PSN inhibits pulmonary eosinophil infiltration, goblet cell hyperplasia, mucus secretion, IgE and Th2 cytokine (IL-4, IL-5, IL-13 and IL-33) production by using DRA (dust mites, ragweed and aspergillus)-induced murine asthma model. Moreover, PSN also attenuated the expression of Arginase-1 (Arg-1), Ym-1 and Fizz-1, markers of AAM (alternatively activated macrophage) polarization, in lung tissues. In addition, PSN attenuated IL-4-induced expression of Arg-1, Ym-1 and Fizz-1 in bone marrow derived macrophages (BMDMs). Treatment with PSN decreased IL-4-induced STAT6 phosphorylation, KLF4 and IRF4 expression in BMDMs. Collectively, our results indicated that PSN ameliorates AAM polarization and asthmatic inflammation and might be a potential agent for treating asthma., (Copyright © 2018 Elsevier Inc. All rights reserved.)

MAPK-activated protein kinase 2 (MK2) plays a critical role in the development of inflammation. However, the modulatory mechanisms in macrophage activation and acute lung injury (ALI) have not been completely defined. Here, we reported that MK2-deficient mice (MK2 -/- ) protected against sepsis-induced ALI. In response to lipopolysaccharide (LPS) challenge, MK2 -/- mice and myeloid cell-specific MK2 conditional knockout mice (MK2 Lyz2-KO ) exhibited attenuated inflammatory response, especially producing fewer amounts of tumor necrosis factor-α (TNF-α), interleukin (IL)-6, and macrophage inflammatory protein 2 (MIP-2). LPS treatment in vitro resulted in reduced cytokine expression in MK2 -/- bone marrow-derived macrophages (BMDMs). Furthermore, we found that LPS-induced microRNA lethal-7e ( let-7e) expression was significantly increased in MK2 -/- macrophages. Transfection of let-7e antagomirs into MK2 -/- BMDM rescued LPS-induced expression of TNF-α, IL-6, and MIP-2. In contrast, transfection of let-7e mimics into MK2 +/+ BMDM decreased cytokine expression. Meanwhile, LPS-induced phosphorylation of cAMP response element-binding (CREB) protein, a substrate of MK2, was downregulated in MK2 -/- BMDMs. Lin28, an inhibitory molecule of let-7, was significantly reduced in MK2 -/- macrophages. Our results suggested that MK2 boosts LPS-induced macrophage activation and ALI via increasing activation of CREB and consequently, the expression of Lin28 and downregulation of let-7e.

Sepsis caused by Gram-negative bacteria is one of major causes for the progression of acute lung injury (ALI) with limited treatment and effective medicines. Tabersonine is an indole alkaloid mainly isolated from Catharanthus roseus, and a potential drug candidate for treatment of cancer and Alzheimer's disease (AD), however, its anti-inflammatory effect has not been revealed. In this study, we reported that tabersonine ameliorated lipopolysaccharides (LPS)-induced ALI in vivo and inhibited LPS-mediated macrophage activation in vitro. By using murine ALI model, we found that tabersonine significantly attenuated LPS-induced pathological injury in the lung. Tabersonine also inhibited LPS-mediated neutrophil infiltration, elevation of MPO activity and the production of TNF-α, IL-6 and IL-1β. Furthermore, tabersonine inhibited LPS-induced the production of pro-inflammatory mediators such as iNOS, NO and cytokines by suppressing NF-κB and p38 MAPK/MK2 signaling cascades. Tabersonine reduced the K63-linked polyubiquitination of TRAF6. Taken together, these results suggested that tabersonine has anti-inflammatory activities in vitro and in vivo, and is a potential therapeutic candidate for the treatment of ALI/ARDS., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Gastric cancer is the third common cause of cancer mortality in the world with poor prognosis and high recurrence due to lack of effective medicines. Our studies revealed that lanatoside C, a FDA-approved cardiac glycoside, had an anti-proliferation effect on different human cancer cell lines (MKN-45; SGC-7901; HN4; MCF-7; HepG2) and gastric cell lines MKN-45 and SGC-7901 were the most sensitive cell lines to lanatoside C. MKN-45 cells treated with lanatoside C showed cell cycle arrest at G2/M phase and inhibition of cell migration. Meanwhile, upregulation of cleaved caspase-9 and cleaved PARP and downregulation of Bcl-xl were accompanied with the loss of mitochondrial membrane potential (MMP) and induction of intracellular reactive oxygen species (ROS). Lanatoside C inhibited Wnt/β-catenin signaling with downregulation of c-Myc, while overexpression of c-Myc reversed the anti-tumor effect of lanatoside C, confirming that c-Myc is a key drug target of lanatoside C. Furthermore, we discovered that lanatoside C prompted c-Myc degradation in proteasome-ubiquitin pathway with attenuating the binding of USP28 to c-Myc. These findings indicate that lanatoside C targeted c-Myc ubiquitination to inhibit MKN-45 proliferation and support the potential value of lanatoside C as a chemotherapeutic candidate., (Copyright © 2018 Elsevier Inc. All rights reserved.)

In this study, a rapid, simple and sensitive analytical method was developed for the quantitative determination of 20 nucleosides and nucleobases in functional foods at trace levels using hydrophilic interaction ultra-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (HILIC-UPLC-TQ-MS/MS) in multiple-reaction monitoring (MRM) mode. Under optimised chromatographic conditions, good separation of 20 target compounds was achieved using a Waters Acquity UPLC BEH Amide column and gradient elution in 11min. The limits of detection (LODs) and quantification (LOQs) were between 0.02-42.54ng/mL and 0.05-98.18ng/mL for the 20 analytes, respectively. This is the first report about simultaneous analysis of nucleosides and nucleobases in functional foods using this method, which afforded good linearity, precision, repeatability and accuracy. The method developed was successfully applied to quantify target compounds in batches of ginkgo seeds. The method potentially could be used to determine polar and trace-level nucleosides and nucleobases in ginkgo seeds., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

A novel and generally applicable approach was established for the herb-herb interaction analysis when decocting together by using ultra-high-performance liquid chromatography coupled with a triple quadrupole electrospray tandem mass spectrometer and fuzzy chemical identification with poly-proportion design. A simple programme was originally developed for the rapid identification and classification of herbal constituents on the basis of the establishment of herbal constituent databases, recognition of the reference compound peaks, selection of the diagnostic ions or fragmentation pathways, classification of chemical groups and formation of group networks. In this study, the exact structures of the chemical constituents did not need to be determined, and only the constituents attributed to different groups were further considered for quantitative analysis. Such a novel approach was successfully applied to kansui-licorice interaction analysis when decocting together. A total of 26 constituents from kansui and 45 constituents from licorice were classified into different chemical groups, and they were further quantitatively analyzed on the basis of semi-symmetric proportion design. The results showed that kansui could significantly promote the concentration of most triterpenoid saponins, phenylpropanoids and their glycosides (the constituents from licorice) in solution when co-decocting, and licorice could clearly promote the concentration of most diterpenes and triterpenes (the constituents from kansui) in solution, potentially explaining the incompatibility of kansui and licorice. Overall, the presently developed strategy should be useful for the interaction analysis for complex mixtures containing various complicated constituents, such as herbal, environmental, agricultural and biological samples., (Copyright © 2013 Elsevier B.V. All rights reserved.)