Effects of Lidocaine-Derived Organic Compounds on Eosinophil Activation and Survival.

Lidocaine, a local anesthetic, is known to possess anti-inflammatory properties. However, its clinical use is limited by inconveniences, such as its local synesthetic effects. This study evaluated lidocaine analogs designed and synthesized to overcome the disadvantages of lidocaine, having anti-inflammatory properties. Interleukin 5 (IL-5)-induced eosinophil activation and survival were evaluated using 36 lidocaine analogs with modified lidocaine structure on the aromatic or the acyl moiety or both. Eosinophil survival was evaluated using a CellTiter 96® aqueous cell proliferation assay kit. Superoxide production was determined using the superoxide dismutase-inhibitable reduction of cytochrome C method. Eosinophil cationic protein (ECP), IL-8, and transcription factor expression were determined using enzyme-linked immunosorbent assay. The platelet-activating factor (PAF)-induced migration assay was performed using a Transwell insert system. Compounds EI137 and EI341 inhibited IL-5-induced eosinophil survival and superoxide and ECP production in a concentration-dependent manner. These compounds also significantly reduced IL-8 production. Although compounds EI137 and EI341 significantly reduced phosphorylated ERK 1/2 expression, they did not influence other total and phosphorylated transcription factors. Moreover, 1000 µM of compound EI341 only inhibited PAF-induced migration of eosinophils. Lidocaine analogs EI137 and EI341 inhibited IL-5-mediated activation and survival of eosinophils. These compounds could be new therapeutic agents to treat eosinophilic inflammatory diseases.

Combined experimental/computational aspects for the molecular interaction of empagliflozin with bovine serum albumin: Quantification and application to human plasma.

Empagliflozin (EMP) is an oral antihyperglycemic agent for type 2 diabetic patients. The molecular binding of EMP to bovine serum albumin (BSA) was elucidated by a combined experimental/computational approach to fulfil the pharmacokinetics and pharmacodynamics gaps of the cited drug for further development. Fluorescence, synchronous, and three-dimensional fluorescence spectroscopy verified that EMP quenched BSA native fluorescence through a dual static/dynamic mechanism that was further supported by FÓ§rster resonance energy transfer and ultraviolet absorption spectroscopy. Fourier transform infrared spectroscopy revealed the conformational variations in BSA secondary structure induced by EMP. Thermodynamic properties of the BSA-EMP complex were also investigated, and the hydrophobic interactions' role in the binding process was demonstrated by the computed enthalpy (ΔH = 6.558 kJ mol-1 ) and entropy (ΔS = 69.333 J mol-1  K-1 ). Gibbs free energy (ΔG) values were negative at three distinct temperatures, illuminating the spontaneity of this interaction. In addition, molecular docking studies depicted the optimal fitting of EMP to BSA on Site I (sub-domain IIA) through three hydrogen bonds. Additionally, and based on the quenching effect of EMP on BSA fluorescence, this study suggests a simple validated spectrofluorometric method for the quantitation of the studied drug in bulk form and human plasma samples with reasonable recoveries (96.99-103.10%).

Phytochemical investigation, molecular docking studies and DFT calculations on the antidiabetic and cytotoxic activities of Gmelina philippensis CHAM.

ETHNOPHARMACOLOGICAL RELEVANCE: Gmelina philippensis CHAM is an ornamental plant that is distributed in South Asia and warm regions of the Mediterranean area. The plant is traditionally applied in folk medicine for the treatment of diabetes. AIM OF THE STUDY: To evaluate the cytotoxic and the antidiabetic activities of the ethanolic extract of G. philippensis aerial parts. To isolate the metabolite(s) responsible for these activities and to elucidate the mechanism of action by molecular docking study. MATERIALS AND METHODS: Compounds (1-11) were isolated using various chromatographic techniques and their structures were determined by NMR spectroscopic and mass spectrometric analysis. The cytotoxic effect was tested using viability test and MTT assay. Antidiabetic activity was evaluated by measuring the inhibitory activity of the ethanolic extracts and compounds against α-glucosidase and α-amylase activities. Modeling and docking simulations were performed using Molecular Operating Environment software and the crystal structure of protein kinases CDK2, (1PYE) and AKT1 (4GV1), in addition to α-glucosidase (3TOP) and α-amylase (2QV4). RESULTS: Compounds 2, 3 and 8 were isolated for the first time from the plant and identified as: gmelinol (2), apigenin (3) and tyrosol (8). While ß-sitosterol-3-O- ß-D-glucopyranoside (4) vicenin-II (7), rhoifolin (9), isorhoifolin (11) were isolated for the first time from the genus, along with and the new iridoid 6-O-α-L-(2″-O-benzoyl-4″-O-trans-p-methoxycinnamoyl)rhamnopyranosyl-1α- ß-D-glucopyranoside catalpolgenin (6). In addition, to the previously reported compounds: mixture of ß -sitosterol and stigmasterol (1), and 6- O- α-L-(2″,3″,4″-tri-O -benzoyl)rhamnopyranosylcatalpol (5) and 6-O-α-L-(2″-O-trans-p-methoxycinnamoyl)rhamnopyranosylcatalpol (10). The cytotoxic activity against hepatocellular carcinoma (HepG-2) cell lines for compounds 2, 5, 7, 9 and 11 was conducted using cisplatin as a standard. Gmelinol (2) exhibited strong cytotoxic activity against HepG-2 cell lines with IC 50 value of 3.6 ± 0.1 µg/ml which is more potent than the standard cisplatin IC 50 = 8.7 ± 0.9 µg/ml. Molecular modeling of 2 against diverse targets of protein kinases suggested that CDK-2 and AKT-1 could be the dual probable kinase targets for its cytotoxic action. Compound 2 showed α-amylase inhibition activity with IC 50 value of 60.9 (µg/ml) while, compounds 5 showed strong α-glucosidase inhibition activity with IC 50 values of 41.7 (µg/ml) compared to acarbose with IC 50 value of 34.7, 30.6 (µg/ml). Molecular docking of compounds 2 and 5 on α-glucosidase (3TOP) and α-amylase (2QV4) enzymes revealed high binding affinity and active site interactions comparable to native ligand acarbose. CONCLUSION: The ethanolic extract of G. philippensis CHAM aerial parts is effective against HepG-2 cell lines, α-amylase and α-glucocidase activities. Biologically guided isolation indicated that compounds 2 and 5 are responsible for these activities. These results were supported by DMF calculations that detected the molecular areas responsible for protein interactions shown via docking studies.

Computational Analysis of SAM Analogs as Methyltransferase Inhibitors of nsp16/nsp10 Complex from SARS-CoV-2.

Methyltransferases (MTases) enzymes, responsible for RNA capping into severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), are emerging important targets for the design of new anti-SARS-CoV-2 agents. Here, analogs of S-adenosylmethionine (SAM), obtained from the bioisosteric substitution of the sulfonium and amino acid groups, were evaluated by rigorous computational modeling techniques such as molecular dynamics (MD) simulations followed by relative binding free analysis against nsp16/nsp10 complex from SARS-CoV-2. The most potent inhibitor (2a) shows the lowest binding free energy (-58.75 Kcal/mol) and more potency than Sinefungin (SFG) (-39.8 Kcal/mol), a pan-MTase inhibitor, which agrees with experimental observations. Besides, our results suggest that the total binding free energy of each evaluated SAM analog is driven by van der Waals interactions which can explain their poor cell permeability, as observed in experimental essays. Overall, we provide a structural and energetic analysis for the inhibition of the nsp16/nsp10 complex involving the evaluated SAM analogs as potential inhibitors.

In Silico Study towards Repositioning of FDA-Approved Drug Candidates for Anticoronaviral Therapy: Molecular Docking, Molecular Dynamics and Binding Free Energy Calculations.

The SARS-CoV-2 targets were evaluated for a set of FDA-approved drugs using a combination of drug repositioning and rigorous computational modeling methodologies such as molecular docking and molecular dynamics (MD) simulations followed by binding free energy calculations. Six FDA-approved drugs including, Ouabain, Digitoxin, Digoxin, Proscillaridin, Salinomycin and Niclosamide with promising anti-SARS-CoV-2 activity were screened in silico against four SARS-CoV-2 proteins-papain-like protease (PLpro), RNA-dependent RNA polymerase (RdRp), SARS-CoV-2 main protease (Mpro), and adaptor-associated kinase 1 (AAK1)-in an attempt to define their promising targets. The applied computational techniques suggest that all the tested drugs exhibited excellent binding patterns with higher scores and stable complexes compared to the native protein cocrystallized inhibitors. Ouabain was suggested to act as a dual inhibitor for both PLpro and Mpro enzymes, while Digitoxin bonded perfectly to RdRp. In addition, Salinomycin targeted PLpro. Particularly, Niclosamide was found to target AAK1 with greater affinity compared to the reference drug. Our study provides comprehensive molecular-level insights for identifying or designing novel anti-COVID-19 drugs.

Novel Azine Linked Hybrids of 2-Indolinone and Thiazolodinone Scaffolds as CDK2 Inhibitors with Potential Anticancer Activity: In Silico Design, Synthesis, Biological, Molecular Dynamics and Binding Free Energy Studies.

Molecular hybrid of 2-indolinone-thiazolidinone is a well known scaffold for variable biological activities including anticancer activity. Accordingly, in the current work aided with structure-based molecular modeling studies, a library of novel twenty-six hybrids, 4(a-z), was designed and synthesized. Docking studies in the active site of CDK2, one of the key checkpoints enzymes, revealed that the binding scores of the designed molecules are comparable to the reference enzyme's inhibitors Sunitinib, Nintedanib, and Semaxanib. Variable antiproliferative activities are shown for these molecules against human liver (HepG2), breast (MCF7), and colon (HCT-29) cell lines considering Doxrubacin as a refrence drug. Compared to cytotoxic activities on the normal fibroblasts (WI-38), the tested molecules had better selectivity against the cancerous cells, expressed by their selectivity index (SI), than Doxrubacin and compound 4i was the safest compound. CDK2 inhibitory results of compounds 4f, 4g, 4h, and 4w showed IC50 at 59.43, 143.6, 27.42, and 61.63 nM respectively, while that of Sunitinib was 23.8 nM. To clarify the obtained biological activities of these molecules, broad docking and molecular dynamic simulations studies were undertaken and confirmed the consistency between the computational and the in vitro CDK2 inhibitory activities. Furthermore, in silico ADME/Tox profiles were done for the most active molecules using SwissADME and pkCSM-pharmacokinetics web-based methods predicted good pharmacokinetics, bioavailability, and toxicity profiles for the tested compounds.

Ionic liquid of ketoprofen-piperine modulates the pharmaceutical and therapeutic characters of ketoprofen.

Efficiency of drug delivery is product of drug properties and formulation design. Modulating drug's unfavorable properties such as poor solubility or permeation is the first step towards optimum delivery. By combining a drug with a selected bulky counter ion, it can be transformed into a low-melting point salt, i.e., an ionic liquid (IL), with favorable physicochemical properties. In this study, we prepared a novel IL of anti-inflammatory drug, ketoprofen (KP), to enable its transdermal administration. KP was paired with piperine (PI) forming equimolar KP-PI IL, via solvent evaporation. KP-PI IL showed extended stability. Thermal analysis and X-ray diffractometry proved that KP was transformed into a low-melting point amorphous form, while spectroscopic analysis and computational studies demonstrated that KP-PI interaction was mediated by hydrogen bonding. In the IL form, KP's solubility increased due to IL formation by 71 to 83%, while 218% more KP was permeated through rat skin in the IL form, than in a KP/PI mixture. Importantly, upon transdermal administration to rats with induced paw edema; KP-PI IL resulted in a 68% less paw swelling than KP/PI mixture. These findings demonstrate the utility of IL as an economic, simple and efficient strategy for improving the therapeutic application of drugs/drug combinations.

Synthesis, biological evaluation, and molecular modeling studies of acetophenones-tethered 1,2,4-triazoles and their oximes as epidermal growth factor receptor inhibitors.

A series of 5-(4-pyridyl)-1,2,4-triazoles hybrids with acetophenones and their oxime derivatives was rationally designed and synthesized as epidermal growth factor receptor (EGFR) kinase inhibitors. Initially, drug Likeness and pharmacokinetics properties of the prepared compounds were evaluated. Afterward, the prepared compounds were in vitro screened for their ability to inhibit the growth of the NCI-60 human cancer cell lines where certain compounds showed moderate activity. Compounds 4e and 5b emerged as the most potent compounds in this series were further tested for their EGFR enzyme inhibition activity. They showed IC50 values of 0.14 and 0.18 µM, respectively, in comparison with Gefitinib as a reference with an IC50 value of 0.06 µM. Docking of compounds 4e and 5b into the binding site of EGFR tyrosine kinase was performed to explains their possible binding mode and to compare it with known inhibitors. Moreover, molecular dynamic simulations were estimated for deeper understanding of the binding mode of compounds 4e and 5b at the binding site of EGFR tyrosine kinase. The findings indicated that the novel ligands 4e and 5b were stable in the EGFR tyrosine kinase active site.

Innovative computationally designed-spectrofluorimetric method for determination of modafinil in tablets and human plasma.

A novel computationally designed-spectrofluorimetric method for the determination of a unique antinarcoleptic drug; modafinil (MDF) in tablets and human plasma was theoretically and experimentally established. Firstly, a density functional theory (DFT) computations were performed to investigate MDF-Tb3+ complex formation and to study the affinity of Tb3+ to MDF in aqueous solution. The computed formation energy of [Tb (MDF)4]3+ (ΔG= -246.0 kcal/mol) assured the ability of Tb3+ to recognize MDF in water and proved the strong nature of the Tb3+-O coordination bonds in addition to some contribution from inter-ligand hydrophobic interactions. Hence, a spectrofluorimetric method was optimized and validated depending on MDF quenching effect on Tb3+ fluorescence via fluorescence resonance energy transfer from Tb3+ to MDF. The formed [Tb (MDF)4]3+ complex was measured at λex. 222 nm/λem. 497 nm against a reagent blank. The Tb3+ fluorescence was significantly reduced upon addition of MDF (linearity range= 0.5-20.0 µg/mL). Detection and quantification limits were 0.129 and 0.391 µg/mL, respectively. Good recoveries (97.47-101.92%) were obtained upon application of the proposed method for the assessment of the target drug in bulk powder, tablets and plasma. According ICH guidelines, the results of the established method were statistically analyzed and validated.

Design and synthesis of novel isatin-based derivatives targeting cell cycle checkpoint pathways as potential anticancer agents.

In recent years, cell cycle and checkpoint pathways regulation are offering new therapeutic approaches against cancer. Isatin, is a well exploited scaffold in the anticancer domain. Accordingly, the current work describes the design and synthesis of two series of (Z)-3-substituted-2-(((E/Z)-5-substituted-2-oxo-1-substituted-indolin-3-ylidene)hydrazinylidene)-thiazolidin-4-ones, 4(a-s) and (E/Z)-1-substituted-3-(((Z)-3-substituted-4-methylthiazol-2(3H)-ylidene)hydrazineylidene)-5-substituted-indolin-2-ones, 5(a-s). The structures of the synthesized molecules were confirmed by spectral and elemental methods of analyses. Pure diastereomers were further identified with 1H-1H-NOESY and confirmed with X-ray crystallography. The target compounds were tested in vitro for their cytotoxicity against three human epithelial cell lines, liver (HepG2), breast (MCF-7), and colon (HT-29) in addition to the diploid human normal cells (WI-38) compared to doxorubicin as a reference drug. Variable cytotoxic effects (IC50 3.29-100 µmol) were reported on the three cancer cell lines with pronounced selectivity compared to the normal one WI-38. The potency of the most active compounds, 4o, 4s, 5e, 5f, 5l, 5m and 5o (IC50 3.29-9.92 µmol), in both series associated with the (Z) configurations of N = thiazolidin/ene or one, however, the configuration of the N = isatin moiety seemed to be of no importance to the activity. The tested compounds were grouped for their possible mechanism of action into 4 categories. Compound 4o with no apparent effect on all genes examined. Compounds 4s and 5o affected all genes investigated and seem to have multiple cellular targets; induced the expression of p53 and caspases, and downregulated that of CDK1. Compounds 5l and 5m directly elevated the expression of initiator and effector caspases without going through p53 pathway. Finally, compounds 5e and 5f elevated the expression of p53 and inhibited CDK1. Compounds 4s, 5e, 5f, 5l, 5m, and 5o caused a significant elevation in the activity of cleaved caspase 3 as well. Docking studies on CDK1 revealed that the active molecules bind to the tested enzyme by the same manner of the co-crystallized ligands and the isatin-thiazoldinone/ene scaffold is essential for binding of these molecules.