3D QSAR studies, pharmacophore modeling, and virtual screening of diarylpyrazole-benzenesulfonamide derivatives as a template to obtain new inhibitors, using human carbonic anhydrase II as a model protein.

A 3D-QSAR modeling was performed on a series of diarylpyrazole-benzenesulfonamide derivatives acting as inhibitors of the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1). The compounds were collected from two datasets with the same scaffold, and utilized as a template for a new pharmacophore model to screen the ZINC database of commercially available derivatives. The datasets were divided into training, test, and validation sets. As the first step, comparative molecular field analysis (CoMFA), CoMFA region focusing and comparative molecular similarity indices analysis (CoMSIA) in parallel with docking studies were applied to a set of 41 human (h) CA II inhibitors. The validity and the prediction capacity of the resulting models were evaluated by leave-one-out (LOO) cross-validation approach. The reliability of the model for the prediction of possibly new CA inhibitors was also tested.

Printing a cure: A tailored solution for localized drug delivery in liver cancer treatment.

Adjuvant chemotherapy is highly recommended for liver cancer to enhance survival rates due to its tendency to recur frequently. Localized drug-eluting implants have gained traction as an alternative to overcome the limitations of systemic chemotherapy. This work describes the development of biodegradable 3D printed (3DP) bilayer films loaded with 5-fluorouracil (5FU) and cisplatin (Cis) with different infill percentages where the 5FU layers were 40%, 30%, and 30% and Cis layers were 10%, 15%, and 10% for films A, B, and C, respectively. The relevant characterization tests were performed, and the drug content of films was 0.68, 0.50, and 0.50 mg of 5FU and 0.39, 0.80, and 0.34 mg of Cis for films A, B, and C, respectively. Cis release was affected by the alterations to the film design, where films A, B, and C showed complete release at 12, 14, and 23 days, respectively. However, 5FU was released over 24 h for all films. The films were stable for up to two weeks after storage at 25 °C/65% relative humidity and four weeks at 4 °C where drug content, tensile strength, FTIR, and thermal analysis results demonstrated negligible alterations. The cytotoxicity of the films was assessed by MTS assays using HepG2 cell lines demonstrating up to 81% reduction in cell viability compared to blank films. Moreover, apoptosis was confirmed by Western Blots and the determination of mitochondrial cell potential, highlighting the potential of these films as a promising approach in adjuvant chemotherapy.

Characterisation of cytochrome P450 isoenzyme activity in sheep liver and placental microsomes.

INTRODUCTION: Drug metabolism during pregnancy is a complex process that involves maternal, placental and fetal sites of metabolism. Indeed, there is a lack of clarity provided from drug metabolism in human pregnancy due to ethical limitations. Large animal models of human pregnancy provide an opportunity to quantify activity of phase 1 drug metabolism mediated by cytochrome P450 (CYP) enzymes in the maternal, placental, and fetal compartments. Herein, we have validated a comprehensive assay to quantify maternal, placental, and fetal CYP activity. METHODS: Isolated microsomes from sheep maternal liver, placenta, and fetal liver (140d gestation, term = 150d) were incubated with CYP-specific probe drugs to quantify the activity of CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1 and CYP3A. Inhibition studies were performed to validate specificity of probe drugs. The validated assay was developed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). RESULTS: CYP1A2, CYP2B6, CYP2C8, CYP2C19, CYP2D6, CYP2E1 and CYP3A were active in maternal liver. In contrast, only CYP1A2, CYP2C8 and CYP2D6 were active in the placenta, whereas CYP2B6, CYP2C8 and CYP2D6 were active in the fetal liver. Of the placental-specific CYPs validated, CYP1A2 increased in type A compared with type D placentomes, whereas CYP2C8 activity increased in type B compared with type A and C. DISCUSSION: This study has established conditions for compartment-specific CYP activity in the sheep maternal-placental-fetal unit using a validated and standardised experimental workflow. Compartment- and placentome type-specific CYP activity are important considerations when examining drug metabolism in the maternal-placental-fetal unit and in determining the impact of pregnancy complications.

Nanotechnology and narasin: a powerful combination against acne.

Acne vulgaris is widely regarded as the most prevalent skin disorder characterized by painful, inflammatory skin lesions that are primarily attributed to the pathogenic actions of Cutibacterium acnes (C. acnes). To improve the clinical management of this disease, there is a pressing clinical demand to develop innovative antibacterial therapies that utilize novel mechanisms. The current research aimed to discover the antibacterial efficacy of narasin (NAR), a polyether ionophore, against drug-resistant acne bacteria. In addition, the study aimed to formulate self-nanomicellizing solid dispersions (SNMSD), utilizing Soluplus® (SOL), as a drug delivery system to incorporate NAR and selectively target the lipophilic C. acnes abundant environments within the skin. Furthermore, the study aimed to investigate the ex vivo deposition and permeation of NAR into the various layers of the skin using full-thickness porcine ear skin as a model skin. By encapsulating NAR within spherical polymeric micelles (dn < 80 nm) aqueous solubility was significantly increased by approximately 100-fold (from <40 µg mL-1 to 4600 µg mL-1). Following optimization, the micelle solution was integrated into a gel formulation (containing 0.2% w/v NAR) and evaluated for stability over 4 weeks at room temperature (drug content >98%). Results from drug deposition and permeation experiments demonstrated that the deposition of NAR from the NAR-micelle solution and its gel formulation into the lipophilic stratum corneum (19 835.60 ± 6237.89 ng cm-2 and 40 601.14 ± 3736.09 ng cm-2) and epidermis (19 347 ± 1912.98 ng cm-2 and 18 763.54 ± 580.77 ng cm-2) was superior to that of NAR in solution, which failed to penetrate any skin layers. In conclusion, the outcomes of this study provide evidence that NAR exhibits promising activity against antimicrobial resistant strains of C. acnes (MIC range ≤0.008-0.062) and that micelle nanocarriers can improve the aqueous solubility of poorly water-soluble drugs. Furthermore, our results highlight the ability of nanomicelles to enable selective and targeted drug delivery to the lipophilic skin layers.

Hormetic effects of curcumin on oxidative stress injury induced by trivalent arsenic in isolated rat hepatocytes.

Objective: Arsenic (As) poisoning is a worldwide public health problem. Arsenic can cause cancer, diabetes, hepatic problems, etc. Hence, we investigated possible hepatoprotective properties of curcumin against As3+-induced liver damages in freshly isolated rat hepatocytes. Materials and Methods: Isolation of hepatocytes was done by the two-step liver perfusion method using collagenase. The EC50 concentration of As3+ was used in toxicity assessments and curcumin (2, 5, and 10 µM) was added 15 min before As3+ addition to isolated hepatocytes. Curcumin impact was assessed in terms of cytotoxicity, lipid peroxidation induction, reactive oxygen species (ROS) levels, and mitochondrial membrane potential. Results: As3+ significantly increased cytotoxicity, malondialdehyde and ROS levels and induced mitochondrial membrane damage and hepatocyte membrane lysis after 3 hr incubation. Curcumin 2 µM significantly prevented lipid peroxidation induction, ROS formation, and mitochondrial membrane damage; while curcumin 5 µM had no apparent effect on these parameters, curcumin 10 µM potentiated them. Conclusion: Curcumin only at low doses could ameliorate oxidative stress injury induced by As3+ in isolated rat hepatocytes.

Synthesis and Evaluation of the Antimicrobial Activity of Spiro-4H-pyran Derivatives on Some Gram Positive and Gram Negative Bacteria.

Infections are one of the most important causes of death, disability and inappropriate conditions for millions of people around the world. Therefore, the development in prognosis, prevention and treatment of infectious diseases made a considerable progress in designing and synthesis of new antimicrobial drugs. Nowadays, due to the increase in microbial resistance, discovery of new compounds with broad spectrum effects is granted. 4H-pyran derivatives and spiro compounds are the most important fragments in some effective drugs with antimicrobial activity. Therefore, in this study, 6 compounds with spiro-4H-pyran core were synthesized and evaluated for their antimicrobial activity against four different bacterial species using microbroth dilution and disk diffusion methods. Minimum inhibitory concentration (MIC) has been measured for each compound and also for the standard antibiotic, gentamicin, and they were all compared together. According to our result, one of the spiropyran derivative (5d) containing both the indole and the cytosine ring, has been shown good antibacterial effects against standard and clinical isolates of Staphylococcus aureus and Streptococcus pyogenes.

Design, Synthesis and Cytotoxicity Evaluationof New 1,2-diaryl-4, 5, 6, 7-Tetrahydro-1H-benzo[d] Imidazolesas Tubulin Inhibitors.

A new series of 1,2-diaryl-4,5,6,7-tetrahydro-1H-benzo[d]imidazoles, possessing trimethoxyphenyl pharmacophore, were synthesized to evaluate their biological activities as tubulin inhibitors. Cytotoxic activity of the synthesized compounds 7a-f was assessed against several human cancer cell lines, including MCF-7 (breast cancer cell), HEPG2 (liver hepatocellular cells), A549 (adenocarcinomic human alveolar basal epithelial cells), T47D (Human ductal breast epithelial tumor cell line) and fibroblast. According to our results, HEPG2 seems to be the most sensitive, while MCF7 was the most resistant cell line to the compounds. All the compounds expect 7b, possessed satisfactory activity against HEPG2 with mean IC50 values ranging from 15.60 to 43.81 µM.

Synthesis and Molecular-cellular Mechanistic Study of Pyridine Derivative of Dacarbazine.

Dacarbazine is an antitumor prodrug which is used for the treatment of malignant metastatic melanoma and Hodgkin's disease. It requires initial activation in liver through an N-demethylationreaction. The active metabolite prevents the progress of disease via alkylation of guanine bases in DNA strands. In order to investigate the importance of imidazole ring and its dynamictautomerization in anticancer activity of dacarbazine, a pyridine analog of this drug was synthesized and the cytotoxic activity and cellular-molecular mechanisms of action for this compound were compared with those of dacarbazine. EC50 values for dacarbazine and the pyridine analog were found to be 56 µM and 33 µM respectively. Both dacarbazine and the pyridine analog resulted in formation of reactive oxygen species (ROS) upon their addition to the isolated rat hepatocytes. They also decreased the mitochondrial membrane potential and causedlysosomal membrane rupture. Cytotoxicity was prevented by ROS scavengers and antioxidants. Cytotoxicity wasalso prevented by CYP450 inhibitors, lysosomalinactivators and MPT (Mitochondrial Permeability Transition Pore) blockers.

Biological reactive intermediates that mediate dacarbazine cytotoxicity.

PURPOSE: In the following, the cellular and molecular mechanism of cytotoxicity induced by prodrug dacarbazine toward the isolated rat hepatocytes was studied. METHOD: Accelerated cytotoxicity screening technique (ACMS) was used to perform this study. RESULT: Addition of dacarbazine to isolated rat hepatocytes resulted in reactive oxygen species (ROS) formation, and lysosomal membrane leakiness before hepatocyte lysis occurred. Hepatocyte ROS generation was inhibited by desferoxamine (a ferric chelator). Cytotoxicity was prevented by antioxidants or ROS scavengers (mannitol or dimethylsulfoxide), cytochorome P450 inhibitors (phenylimidazole, diphenyliodonium chloride, 4-methylpyrazole, and benzylimidazole). In addition to lysosomal damage, dacarbazine caused hepatocyte protease activation and cell proteolysis. CONCLUSION: Dacarbazine cytotoxicity is associated with ROS (H(2)O(2), O(2)(*-) ) generation. It is suggested that H(2)O(2) could cross the lysosomal membrane, react with lysosomal Fe(2+) to form hydroxyl radical (Haber-Weiss reaction) which is the major cause of lysosomal membrane leakiness, proteases, and other digestive enzymes' release and finally the cell death.