Dataset Information

In vitro and in vivo Evaluation of in silico Predicted Pneumococcal UDPG:PP Inhibitors.

ABSTRACT: Pneumonia, of which Streptococcus pneumoniae is the most common causative agent, is considered one of the three top leading causes of death worldwide. As seen in other bacterial species, antimicrobial resistance is on the rise for this pathogen. Therefore, there is a pressing need for novel antimicrobial strategies to combat these infections. Recently, uridine diphosphate glucose pyrophosphorylase (UDPG:PP) has been put forward as a potential drug target worth investigating. Moreover, earlier research demonstrated that streptococci lacking a functional galU gene (encoding for UDPG:PP) were characterized by significantly reduced in vitro and in vivo virulence. Therefore, in this study we evaluated the anti-virulence activity of potential UDPG:PP inhibitors. They were selected in silico using a tailor-made streptococcal homology model, based on earlier listerial research. While the compounds didn't affect bacterial growth, nor affected in vitro adhesion to and phagocytosis in macrophages, the amount of polysaccharide capsule was significantly reduced after co-incubation with these inhibitors. Moreover, co-incubation proved to have a positive effect on survival in an in vivo Galleria mellonella larval infection model. Therefore, rather than targeting bacterial survival directly, these compounds proved to have an effect on streptococcal virulence by lowering the amount of polysaccharide and thereby probably boosting recognition of this pathogen by the innate immune system. While the compounds need adaptation to broaden their activity to more streptococcal strains rather than being strain-specific, this study consolidates UDPG:PP as a potential novel drug target.

SUBMITTER: Cools F

PROVIDER: S-EPMC7373766 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

In vitro and in vivo Evaluation of in silico Predicted Pneumococcal UDPG:PP Inhibitors.

Cools Freya F Triki Dhoha D Geerts Nele N Delputte Peter P Fourches Denis D Cos Paul P

Frontiers in microbiology 20200715

Pneumonia, of which Streptococcus pneumoniae is the most common causative agent, is considered one of the three top leading causes of death worldwide. As seen in other bacterial species, antimicrobial resistance is on the rise for this pathogen. Therefore, there is a pressing need for novel antimicrobial strategies to combat these infections. Recently, uridine diphosphate glucose pyrophosphorylase (UDPG:PP) has been put forward as a potential drug target worth investigating. Moreover, ear ...[more]

PMID: 32760374

Similar Datasets

Project description:Prediction of transcriptional regulatory mechanisms in Arabidopsis has become increasingly critical with the explosion of genomic data now available for both gene expression and gene sequence composition. We have shown in previous work 1, that a combination of correlation measurements and cis-regulatory element (CRE) detection methods are effective in predicting targets for candidate transcription factors for specific case studies which were validated. However, to date there has been no quantitative assessment as to which correlation measures or CRE detection methods used alone or in combination are most effective in predicting TF-->target relationships on a genome-wide scale.We tested several widely used methods, based on correlation (Pearson and Spearman Rank correlation) and cis-regulatory element (CRE) detection (>or=1 CRE or CRE over-representation), to determine which of these methods individually or in combination is the most effective by various measures for making regulatory predictions. To predict the regulatory targets of a transcription factor (TF) of interest, we applied these methods to microarray expression data for genes that were regulated over treatment and control conditions in wild type (WT) plants. Because the chosen data sets included identical experimental conditions used on TF over-expressor or T-DNA knockout plants, we were able to test the TF-->target predictions made using microarray data from WT plants, with microarray data from mutant/transgenic plants. For each method, or combination of methods, we computed sensitivity, specificity, positive and negative predictive value and the F-measure of balance between sensitivity and positive predictive value (precision). This analysis revealed that the >or=1 CRE and Spearman correlation (used alone or in combination) were the most balanced CRE detection and correlation methods, respectively with regard to their power to accurately predict regulatory-target interactions.These findings provide an approach and guidance for researchers interested in predicting transcriptional regulatory mechanisms using microarray data that they generate (or microarray data that is publically available) combined with CRE detection in promoter sequence data.

Project description:Lung cancer is the major cause of cancer deaths worldwide, and it has the highest incidence and mortality rate of any cancer among men and women in China. The first-line therapy for lung cancer treatment is platinum-based chemotherapy drugs such as cisplatin. However, the application of present chemotherapies is limited by severe side effects, which stimulates the discovery of new drugs with new anti-tumor mechanisms and fewer side effects. Beneficially, many antimicrobial peptides (AMPs) from frog skin have been reported to exhibit potent anti-cancer activities with low toxicity, high selectivity and a low propensity to induce resistance. In this study, we first reported an AMP named Dermaseptin-PP, from a rarely studied frog species, Phyllomedusa palliata. Dermaseptin-PP exhibited selective cytotoxicity on H157, MCF-7, PC-3, and U251 MG cancer cells instead of normal HMEC-1 cells with low hemolytic effect. Furthermore, on subcutaneous H157 tumor model of nude mice, Dermaseptin-PP was found to display potent in vivo anti-tumor activity in a dose-related manner without obvious hepatopulmonary side effects. It is widely accepted that AMPs usually work through a membrane disruptive mode, and the confocal laser microscope observation confirmed that Dermaseptin-PP could destroy H157 cell membranes. Further investigation of mechanisms by flow cytometry assay and immunohistochemical analysis unraveled that Dermaseptin-PP also exerted its anti-tumor activity by inducing H157 cell apoptosis via both endogenous mitochondrial apoptosis pathway and exogenous death receptor apoptosis pathway. Herein, we emphasize that the membrane disrupting and the apoptosis activation effects of Dermaseptin-PP both depend on its concentration. Overall, a novel frog skin-derived AMP, named Dermaseptin-PP, was identified for the first time. It possesses strong antimicrobial activity and effective anti-tumor activity by distinct mechanisms. This study revealed the possibility of Dermaseptin-PP for lung cancer treatment and provided a new perspective for designing novel AMP-based anti-tumor candidates with low risk of cytotoxicity.

Project description:The concept of using precipitation inhibitors (PIs) to sustain supersaturation is well established for amorphous formulations but less in the case of lipid-based formulations (LBF). This study applied a systematic in silico-in vitro-in vivo approach to assess the merits of incorporating PIs in supersaturated LBFs (sLBF) using the model drug venetoclax. sLBFs containing hydroxypropyl methylcellulose (HPMC), hydroxypropyl methylcellulose acetate succinate (HPMCAS), polyvinylpyrrolidone (PVP), PVP-co-vinyl acetate (PVP/VA), Pluronic F108, and Eudragit EPO were assessed in silico calculating a drug-excipient mixing enthalpy, in vitro using a PI solvent shift test, and finally, bioavailability was assessed in vivo in landrace pigs. The estimation of pure interaction enthalpies of the drug and the excipient was deemed useful in determining the most promising PIs for venetoclax. The sLBF alone (i.e., no PI present) displayed a high initial drug concentration in the aqueous phase during in vitro screening. sLBF with Pluronic F108 displayed the highest venetoclax concentration in the aqueous phase and sLBF with Eudragit EPO the lowest. In vivo, the sLBF alone showed the highest bioavailability of 26.3 ± 14.2%. Interestingly, a trend toward a decreasing bioavailability was observed for sLBF containing PIs, with PVP/VA being significantly lower compared to sLBF alone. In conclusion, the ability of a sLBF to generate supersaturated concentrations of venetoclax in vitro was translated into increased absorption in vivo. While in silico and in vitro PI screening suggested benefits in terms of prolonged supersaturation, the addition of a PI did not increase in vivo bioavailability. The findings of this study are of particular relevance to pre-clinical drug development, where the high in vivo exposure of venetoclax was achieved using a sLBF approach, and despite the perceived risk of drug precipitation from a sLBF, including a PI may not be merited in all cases.

Project description:BACKGROUND:Several radiolabeled prostate-specific membrane antigen (PSMA) inhibitors based on the lysine-urea-glutamate (KuE) motif as the pharmacophore proved to be suitable tools for PET/SPECT imaging of the PSMA expression in prostate cancer patients. PSMA I&T, a theranostic tracer developed in our group, was optimized through alteration of the peptidic structure in order to increase the affinity to PSMA and internalization in PSMA-expressing tumor cells. However, further structural modifications held promise to improve the pharmacokinetic profile. RESULTS:Among the investigated compounds 1-9, the PSMA inhibitors 5 and 6 showed the highest PSMA affinity (lowest IC50 values) after the introduction of a naphthylalanine modification. The affinity was up to three times higher compared to the reference PSMA I&T. Extended aromatic systems such as the biphenylalanine residue in 4 impaired the interaction with the lipophilic binding pocket of PSMA, resulting in a tenfold lower affinity. The IC50 of DOTAGA-conjugated 10 was slightly increased compared to the acetylated analog; however, efficient PSMA-mediated internalization and 80% plasma protein binding of 68Ga-10 resulted in effective tumor targeting and low uptake in non-target tissues of LNCaP tumor-bearing CD-1 nu/nu mice at 1 h p.i., as determined by small-animal PET imaging and biodistribution studies. For prolonged tumor retention, the plasma protein binding was increased by insertion of 4-iodo-D-phenylalanine resulting in 97% plasma protein binding and 16.1?±?2.5% ID/g tumor uptake of 177Lu-11 at 24 h p.i. CONCLUSIONS:Higher lipophilicity of the novel PSMA ligands 10 and 11 proved to be beneficial in terms of affinity and internalization and resulted in higher tumor uptake compared to the parent compound. Additional combination with para-iodo-phenylalanine in the spacer of ligand 11 elevated the plasma protein binding and enabled sustained tumor accumulation over 24 h, increasing the tumor uptake almost fourfold compared to 177Lu-PSMA I&T. However, high renal uptake remains a drawback and further studies are necessary to elucidate the responsible mechanism behind it.

Dataset Information

In vitro and in vivo Evaluation of in silico Predicted Pneumococcal UDPG:PP Inhibitors.

Publications

<i>In vitro</i> and <i>in vivo</i> Evaluation of <i>in silico</i> Predicted Pneumococcal UDPG:PP Inhibitors.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets