Development of Halogenated-Chalcones Bearing with Dimethoxy Phenyl Head as Monoamine Oxidase-B Inhibitors.

Two series of dimethoxy-halogenated chalcones (DM1−DM20) were synthesized and tested for their ability to inhibit monoamine oxidase (MAOs). Compound DM2 exhibited the most significant inhibition against MAO-B with an IC50 value of 0.067 µM, followed by compound DM18 (IC50 = 0.118 µM), with selectivity index (SI) values of 93.88 and >338.98, respectively. However, none of the substances successfully inhibited MAO-A. The MAO-B inhibitors DM2 and DM18 were competitive and reversible, with Ki values of 0.032 ± 0.004 and 0.045 ± 0.001 µM, respectively. DM2 was non-toxic below 100 µg/mL in the cytotoxic test using the Vero epithelial cell line by the MTT method. According to molecular docking studies, DM2 and DM18 formed very similar conformations within the MAO-B binding pocket, with the ortho-chlorine and ortho-fluorine aromatic rings sandwiched between F168 and Y326. These conformations were predicted to show better interactions with the targeted MAO-B than MAO-A. In particular, the induced-fit docking of the dimethoxy phenyl ring of DM2 facing the hydrophobic pocket made up of FAD, Y398, and Y435 had an impact on F168 in the docking pocket. Taken together, DM2 and DM18 may be suitable candidates for treating neurodegenerative conditions such as Parkinson's disease.

Halogenated Coumarin-Chalcones as Multifunctional Monoamine Oxidase-B and Butyrylcholinesterase Inhibitors.

A series of halogenated coumarin-chalcones were synthesized, characterized, and their inhibitory activities against monoamine oxidases (MAOs), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and ß-site amyloid precursor protein cleaving enzyme 1 (BACE-1) were evaluated. Compound CC2 most potently inhibited MAO-B with an IC50 value of 0.51 µM, followed by CC1 (IC50 = 0.69 µM), with a selectivity index (SI) of >78.4 and >58.0, respectively, over MAO-A. However, none of the compounds effectively inhibited MAO-A, AChE, and BChE, except for CC2 and CC3 inhibiting BChE with IC50 values of 7.00 (SI > 5.73 over AChE) and 11.8 µM, respectively. CC1 and CC2 were found to be reversible and competitive inhibitors of MAO-B, with K i values of 0.50 ± 0.06 and 0.53 ± 0.04 µM, respectively, and CC2 was also a reversible and competitive inhibitor of BChE, with a K i value of 2.84 ± 0.09 µM. The parallel artificial membrane permeability assay (PAMPA) method showed that lead candidates can cross the blood-brain barrier (BBB). The in vitro toxicity analysis on the Vero cell line (Normal African green monkey kidney epithelial cells) by MTT confirmed that both CC1 and CC2 were nontoxic up to 100 µg/mL, which is almost equivalent to 100 times of their effective concentration used in biological studies. In addition, CC1 and CC2 attenuated H2O2-induced cellular damage via their reactive oxygen species (ROS) scavenging effect. These results suggest that CC1 and CC2 are selective and competitive inhibitors of MAO-B, and that CC2 is a selective and competitive inhibitor of BChE. Molecular docking studies of lead compounds provided the possible type of interactions in the targeted enzymes. Based on the findings, both compounds, CC1 and CC2, can be considered plausible drug candidates against neurodegenerative disorders.

Hypothesis validation of rosiglitazone a potential inhibitor against glycogen synthase kinase-3ß, for the management of multifaceted pathophysiology of the diabetic wound: An insilico study.

Diabetic wound (DW) is a major complication of diabetes mellitus that often ends up with amputation of the concerned organ. The current therapies for DW include glucose regulation, wound debridement, pressure off-loading, surgeries, hyperbaric oxygen therapy, maggot therapy, and so on. However, the majority are not meeting all the prerequisites of DW because of extensive pathology and cost associated with the strategies. So, to overcome the problems related to the existing conventional therapies, we hypothesized to repurpose the current drugs, which can target a receptor having a considerable role in the progression of DW might be beneficial. One major challenge of DW is multifaceted pathophysiology includes prolonged inflammation, increased infections, decreased cell proliferation, and migration. Many shreds of evidence disclosed that inhibition of GSK-3ß could result in reduced inflammation and infection, followed by increased cell proliferation and migration. Thus, we selected the GSK-3ß receptor as a ubiquitous target for the treatment of multifactorial pathophysiology of DW. In the current hypothetical study, we investigated the use of rosiglitazone as a therapeutic modulator against the GSK-3ß receptor. To validate our hypothesis, computational studies such as molecular docking and MMGBSA were performed. From the in silico methods, it is evident that rosiglitazone established a higher binding affinity against the selected receptor. Further, the Molecular Dynamic simulation study has revealed stable interaction of rosiglitazone against GSK-3ß complex. Thus, rosiglitazone might be a drug of choice in the therapeutic management of DW.

Quantitation of Ivosidenib, A Novel Mutant IDH1 Inhibitoron Mice DBS: Application to a Pharmacokinetic Study.

Ivosidenib is an approved drug for relapsed or refractory IDH1 mutant AML patients. The goal of the present work is to develop and validate an LC-MS/MS method for the quantitation of ivosidenib in mice dried blood spots (DBS) as per regulatory guideline in the linearity range of 1.10-3293 ng/mL. To date there is no bioanalytical method reported for quantitation of ivosidenib. The chromatographic resolution of ivosidenib and internal standard (warfarin) was achieved on a C18 column with an isocratic mobile phase. All validation parameters met the acceptance criteria. The intra- and inter-day precision was in the range of 2.79-10.5 and 5.76-9.02%, respectively. Ivosidenib was stable for 3 freeze/thaw cycles, up to 7 days at room temperature and for one month at -80°C. The applicability of the validated method is shown in a mice pharmacokinetic study. Ivosidenib was quantifiable up to 24 and 36 h following intravenous and oral administration to mice, respectively. The oral bioavailability was 48%. Comparison of DBS vs. plasma concentrations of ivosidenib showed excellent correlation, indicating DBS can be used as an alternative for plasma for pharmacokinetic analysis.

Quantitative analysis of enasidenib in dried blood spots of mouse blood using an increased-sensitivity LC-MS/MS method: Application to a pharmacokinetic study.

A simple, sensitive and rapid assay method has been developed and validated as per regulatory guidelines for the estimation of enasidenib on mouse dried blood spots (DBS) using liquid chromatography coupled to tandem mass spectrometry with electrospray ionization in the positive-ion mode. The method employs liquid extraction of enasidenib from DBS disks of mouse whole blood followed by chromatographic separation using 0.2% formic acid-acetonitrile (25:75, v/v) at a flow rate of 1.0 mL/min on an Atlantis dC18 column with a total run time of 2.0 min. The MS/MS ion transitions monitored were m/z 474.0 → 267.1 for enasidenib and m/z 309.2 → 251.3 for the internal standard (warfarin). The assay was linear in the range of 1.01-3044 ng/mL. The within-run and between-run precisions were in the range of 3.18-9.06 and 4.66-8.69%, respectively. Stability studies showed that enasidenib was stable on DBS cards for 1 month. This novel method has been applied to analyze the DBS samples of enasidenib obtained from a pharmacokinetic study in mice.

Validated LC-ESI-MS/MS method for the determination of ivosidenib in 10 µL mice plasma: application to a pharmacokinetic study.

A simple, selective and rapid LC-ESI-MS/MS method has been developed and validated for the quantification of ivosidenib in mice plasma using warfarin as an internal standard (I.S.) as per regulatory guideline. Sample preparation was accomplished through a simple protein precipitation process. Chromatography of ivosidenib and the I.S. was achieved on an Atlantis dC18 column using an isocratic mobile phase comprising 0.2 % formic acid in water and acetonitrile (25:75, v/v) delivered at a flow rate of 1.0 mL/min. LC-MS/MS was operated under the multiple reaction-monitoring mode (MRM) using the electrospray ionization technique in positive ion mode and the transitions of m/z 583.1→186.1 and m/z 309.2→251.3 were used to quantitate ivosidenib and the I.S, respectively. The total chromatographic run time was 2.0 min. Linearity was established in the concentration range of 1.10-3293 ng/mL (r2>0.99). The intra- and inter-day accuracy and precision for ivosidenib in mice plasma were in the range of 5.72-9.91 and 5.90-10.7 %, respectively. Ivosidenib was found to be stable on bench-top for 6 h, up to three freeze-thaw cycles, in in-injector for 24 h and for one month at -80 °C. The applicability of the validated method has been demonstrated in a mice pharmacokinetic study. Following intravenous (2 mg/kg) and oral (5 mg/kg) administration of ivosidenib to mice, concentrations were quantifiable up to 24 and 48 h, respectively. The bioavailability was 61 %.

Design, development and permeation studies of nebivolol hydrochloride from novel matrix type transdermal patches.

BACKGROUND: Nebivolol hydrochloride is a third generation ß-blocker with highly selective ß1-receptor antagonist with antihypertensive properties having plasma half life of 10 h and 12% oral bioavailability. The aim of the present investigation was to form matrix type transdermal patches containing Nebivolol hydrochloride to avoid its extensive hepatic first pass metabolism, lesser side effect and increase bioavailability of drug. MATERIALS AND METHODS: Matrix type transdermal patches containing Nebivolol hydrochloride were prepared using EudragitRS100, HPMC K100M (2:8) polymers by solvent evaporation technique. Aluminum foil was used as a backing membrane. Polyethylene glycol (PEG) 400 was used as plasticizer and Dimethyl sulfoxide (DMSO) was used as a penetration enhancer. Drug polymer interactions determined by FTIR and standard calibration curve of Nebivolol hydrochloride were determined by using UV estimation. RESULT: The systems were evaluated physicochemical parameters and drug present in the patches was determined by scanning electron microscopy. All prepared formulations indicated good physical stability. In vitro drug permeation studies of formulations were performed by using Franz diffusion cells using abdomen skin of Wistar albino rat. Result showed best in vitro skin permeation through rat skin as compared to all other formulations prepared with hydrophilic polymer containing permeation enhancer. CONCLUSIONS: IT WAS OBSERVED THAT THE FORMULATION CONTAINING HPMC: EudragitRS100 (8:2) showed ideal higuchi release kinetics. On the basis of in vitro drug release through skin permeation performance, Formulation F1 was found to be better than other formulations and it was selected as the optimized formulation.