Effects of thymoquinone on liver miRNAs and oxidative stress in Ehrlich acid mouse solid tumor model

We investigated the effects of thymoquinone (TQ) on the expression of liver microRNAs (miRNAs), liver histopathology and oxidative stress in Ehrlich acid solid tumor model induced mice. We used 24 male BALB/c mice divided randomly into three groups. Control (C) group mice were injected intraperitoneally (i.p.) with 0.5 ml saline for four weeks. Tumor (T) group mice were injected i.p. with 0.5 ml saline for four weeks, then Ehrlich acid tumor cells were injected subcutaneously into the neck to induce solid tumor formation. TQ (T + Tq) group mice injected i.p. with 10 mg/kg TQ for four weeks, then Ehrlich acid tumor cells were injected subcutaneously into the neck of the mice in this group to induce solid tumor formation. At the end of the study, liver from all groups were removed for histopathological and miRNAs analysis, and oxidative stress measurement. We found that the expression of miR-206b-3p was up-regulated and the oxidative stress and necrosis increased in the liver tissue of mice with Ehrlich acid solid tumor. TQ application decreased the oxidative stress, prevented necrosis, increased regeneration and down-regulated the expression of miR-206b-3p in the liver tissue.     

Alleviating CYP and hERG liabilities by structure optimization of dihydrofuran-fused tricyclic benzo[d]imidazole series – Potent,selective and orally efficacious microsomal prostaglandin E synthase-1 (mPGES-1) inhibitors: Part-2

In an effort to identify CYP and hERG clean mPGES-1 inhibitors from the dihydrofuran-fused tricyclic benzo[d]imidazole series lead 7, an extensive structure-activity relationship (SAR) studies were performed. Optimization of A, D and E-rings in 7 afforded many potent compounds with human whole blood potency in the range of 160–950?nM. Selected inhibitors 21d, 21j, 21m, 21n, 21p and 22b provided selectivity against COX-enzymes and mPGES-1 isoforms (mPGES-2 and cPGES) along with sufficient selectivity against prostanoid synthases. Most of the tested analogs demonstrated required metabolic stability in liver microsomes, low hERG and CYP liability. Oral pharmacokinetics and bioavailability of lead compounds 21j, 21m and 21p are discussed in multiple species like rat, guinea pig, dog, and cynomolgus monkey. Besides, these compounds revealed low to moderate activity against human pregnane X receptor (hPXR). The selected lead 21j further demonstrated in vivo efficacy in acute hyperalgesia (ED₅₀: 39.6?mg/kg) and MIA-induced osteoarthritic pain models (ED₅₀: 106?mg/kg).     

Design and synthesis of 1,4-substituted 1H-1,2,3-triazolo-quinazolin-4(3H)-ones by Huisgen 1,3-dipolar cycloaddition with PI3Kγ isoform selective activity

A strategy for construction of medicinally important 1,4-substituted 1H-1,2,3-triazolo-quinazolin-4(3H)-ones has been devised and presented here. The compounds have been synthesized using one-pot multicomponent strategy under microwave assisted conditions. Triazolyl-quinazolinone based D-ring modified analogs are designed based on IC87114 scaffold, which is first known isoform selective inhibitor of PI3Kδ. Herein, we identified two triazolyl-quinazolinone compounds (5a and 5l) based on same scaffold with PI3Kγ specific inhibitory potential, the selectivity towards this isoform is well supported by in silico results, wherein, these compounds show better interaction and affinity and inhibitory activity for PI3Kγ rather than PI3Kδ. This repositioning of scaffold from PI3Kδ to PI3Kγ isoform can be very useful from medicinal chemistry and drug discovery perspective to unravel molecular interactions of this new scaffold in different cellular pathways.     

Specific Fusion of β-1,4-Endoglucanase and β-1,4-Glucosidase Enhances Cellulolytic Activity and Helps in Channeling of Intermediates

Identification and design of new cellulolytic enzymes with higher catalytic efficiency are a key factor in reducing the production cost of lignocellulosic bioalcohol. We report here identification of a novel β-glucosidase (Gluc1C) from Paenibacillus sp. strain MTCC 5639 and construction of bifunctional chimeric proteins based on Gluc1C and Endo5A, a β-1,4-endoglucanase isolated from MTCC 5639 earlier. The 448-amino-acid-long Gluc1C contained a GH superfamily 1 domain and hydrolyzed cellodextrin up to a five-sugar chain length, with highest efficiency toward cellobiose. Addition of Gluc1C improved the ability of Endo5A to release the reducing sugars from carboxymethyl cellulose. We therefore constructed six bifunctional chimeric proteins based on Endo5A and Gluc1C varying in the positions and sizes of linkers. One of the constructs, EG5, consisting of Endo5A-(G₄S)₃-Gluc1C, demonstrated 3.2- and 2-fold higher molar specific activities for β-glucosidase and endoglucanase, respectively, than Gluc1C and Endo5A alone. EG5 also showed 2-fold higher catalytic efficiency than individual recombinant enzymes. The thermal denaturation monitored by circular dichroism (CD) spectroscopy demonstrated that the fusion of Gluc1C with Endo5A resulted in increased thermostability of both domains by 5°C and 9°C, respectively. Comparative hydrolysis experiments done on alkali-treated rice straw and CMC indicated 2-fold higher release of product by EG5 than that by the physical mixture of Endo5A and Gluc1C, providing a rationale for channeling of intermediates. Addition of EG5 to a commercial enzyme preparation significantly enhanced release of reducing sugars from pretreated biomass, indicating its commercial applicability.     

Secretion of the Human Toll-like Receptor 3 Ectodomain Is Affected by Single Nucleotide Polymorphisms and Regulated by Unc93b1

The innate immune receptor Toll-like receptor 3 (TLR3) can be present on the surface of the plasma membranes of cells and in endolysosomes. The Unc93b1 protein has been reported to facilitate localization of TLR7 and 9 and is required for TLR3, -7, and -9 signaling. We demonstrate that siRNA knockdown of Unc93b1 reduced the abundance of TLR3 on the cell surface without altering total TLR3 accumulation. In addition, siRNA to Unc93b1 reduced the secretion of the TLR3 ectodomain (T3ECD) into the cell medium. Furthermore, two human single nucleotide polymorphisms that affected herpesvirus and influenza virus encephalopathy as well as a natural isoform generated by alternative splicing were found to be impaired for T3ECD secretion and decreased the abundance of TLR3 on the cell surface. The locations of the SNP P554S and the deletion in the isoform led to the identification of a loop in the TLR3 ectodomain that is required for secretion and a second whose presence decreased secretion. Finally, a truncated protein containing the N-terminal 10 leucine-rich repeats of T3ECD was sufficient for secretion in an Unc93b1-dependent manner.     

Effects of l-glutamine supplementation on maternal and fetal hemodynamics in gestating ewes exposed to alcohol

Not much is known about effects of gestational alcohol exposure on maternal and fetal cardiovascular adaptations. This study determined whether maternal binge alcohol exposure and l-glutamine supplementation could affect maternal-fetal hemodynamics and fetal regional brain blood flow during the brain growth spurt period. Pregnant sheep were randomly assigned to one of four groups: saline control, alcohol (1.75–2.5 g/kg body weight), glutamine (100 mg/kg body weight) or alcohol + glutamine. A chronic weekend binge drinking paradigm between gestational days (GD) 99 and 115 was utilized. Fetuses were surgically instrumented on GD 117 ± 1 and studied on GD 120 ± 1. Binge alcohol exposure caused maternal acidemia, hypercapnea, and hypoxemia. Fetuses were acidemic and hypercapnic, but not hypoxemic. Alcohol exposure increased fetal mean arterial pressure, whereas fetal heart rate was unaltered. Alcohol exposure resulted in ~40 % reduction in maternal uterine artery blood flow. Labeled microsphere analyses showed that alcohol induced >2-fold increases in fetal whole brain blood flow. The elevation in fetal brain blood flow was region-specific, particularly affecting the developing cerebellum, brain stem, and olfactory bulb. Maternal l-glutamine supplementation attenuated alcohol-induced maternal hypercapnea, fetal acidemia and increases in fetal brain blood flow. l-Glutamine supplementation did not affect uterine blood flow. Collectively, alcohol exposure alters maternal and fetal acid–base balance, decreases uterine blood flow, and alters fetal regional brain blood flow. Importantly, l-glutamine supplementation mitigates alcohol-induced acid–base imbalances and alterations in fetal regional brain blood flow. Further studies are warranted to elucidate mechanisms responsible for alcohol-induced programming of maternal uterine artery and fetal circulation adaptations in pregnancy.     

A comparative study of cell classifiers for image-based high-throughput screening

Background

Millions of cells are present in thousands of images created in high-throughput screening (HTS). Biologists could classify each of these cells into a phenotype by visual inspection. But in the presence of millions of cells this visual classification task becomes infeasible. Biologists train classification models on a few thousand visually classified example cells and iteratively improve the training data by visual inspection of the important misclassified phenotypes. Classification methods differ in performance and performance evaluation time. We present a comparative study of computational performance of gentle boosting, joint boosting CellProfiler Analyst (CPA), support vector machines (linear and radial basis function) and linear discriminant analysis (LDA) on two data sets of HT29 and HeLa cancer cells.

Results

For the HT29 data set we find that gentle boosting, SVM (linear) and SVM (RBF) are close in performance but SVM (linear) is faster than gentle boosting and SVM (RBF). For the HT29 data set the average performance difference between SVM (RBF) and SVM (linear) is 0.42 %. For the HeLa data set we find that SVM (RBF) outperforms other classification methods and is on average 1.41 % better in performance than SVM (linear).

Conclusions

Our study proposes SVM (linear) for iterative improvement of the training data and SVM (RBF) for the final classifier to classify all unlabeled cells in the whole data set.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2105-15-342) contains supplementary material, which is available to authorized users.