Halogenated class of oximes as a new class of monoamine oxidase-B inhibitors for the treatment of Parkinson's disease: Synthesis, biochemistry, and molecular dynamics study.

Oximes are the promising structural scaffold for inhibiting monoamine oxidase (MAO)-B. Eight chalcone-based oxime derivatives were synthesized by microwave-assisted technique, and their ability to inhibit human MAO (hMAO) enzymes were tested. All compounds showed higher inhibitory activity of hMAO-B than hMAO-A. In the CHBO subseries, CHBO4 most potently inhibited hMAO-B with an IC50 value of 0.031 µM, followed by CHBO3 (IC50 = 0.075 µM). In the CHFO subseries, CHFO4 showed the highest inhibition of hMAO-B with an IC50 value of 0.147 µM. Compound CHBO4 had the highest selectivity index (SI) value of 1290.3. However, CHBO3 and CHFO4 showed relatively low SI values of 27.7 and 19.2, respectively. The -Br substituent in the CHBO subseries at the para-position in the B-ring showed higher hMAO-B inhibition than the -F substituent in the CHFO subseries. In both series, hMAO-B inhibition increased with the substituents at para-position in A-ring (-F > -Br > -Cl > -H in order). Compound CHBO4 (-F in A-ring and -Br in B-ring) was 12.6-times potent than the substituents-reversed compound CHFO3 (-Br in A-ring and -F in B-ring; IC50 = 0.391 µM). In the kinetic study, Ki values of CHBO4 and CHFO4 for hMAO-B were 0.010 ± 0.005 and 0.040 ± 0.007 µM, respectively, with competitive inhibitions. Reversibility experiments showed that CHBO4 and CHFO4 were reversible hMAO-B inhibitors. In the cytotoxicity test using the Vero cells by the MTT technique, CHBO4 had low toxicity with an IC50 value of 128.8 µg/mL. In H2O2-induced cells, CHBO4 significantly reduced cell damage by scavenging reactive oxygen species (ROS). Molecular docking and dynamics showed the stable binding mode of the lead molecule CHBO4 on the active site of hMAO-B. These results suggest that CHBO4 is a potent reversible, competitive, and selective hMAO-B inhibitor and can be used as a treatment agent for neurological disorders.

Metabolomic profiling and biological evaluations of Spongia irregularis-associated actinomycetes supported by multivariate statistical analysis.

AIM: Metabolomic analysis using LC-HRESIMS of 12 extracts of Spongia irregularis-associated actinomycetes for dereplication purposes in addition to evaluation of cytotoxic and antiviral activities of the extracts. METHODS AND RESULTS: In this study, three actinomycetes belonging to the genera Micromonospora, Streptomyces, and Rhodococcus were recovered from the marine sponge Spongia irregularis. Applying the OSMAC approach, each strain was fermented on four different media, resulting in 12 extracts. All extracts were subjected to metabolomic analysis using LC-HRESIMS for dereplication purposes. Multivariate data statistical analysis was carried out for the differentiation between extracts. Additionally, the cytotoxic and anti-hepatitis C virus (anti-HCV) potentials of extracts were evaluated. Most of extracts showed strong to moderate cytotoxicity effects against HepG-2, CACO-2, and MCF-7 cell lines with a general IC50 range of 2.8-8.9 µg/ml. Moreover, the extracts of Micromonospora sp. UR44 using ISP2 and OLIGO media and Streptomyces sp. UR32 using ISP2 medium exhibited anti-HCV activity with IC50 of 4.5 ± 0.22, 3.8 ± 0.18, and 5.7 ± 0.15 µM, respectively. CONCLUSION: Metabolomic analysis of 12 extracts of S. irregularis-associated actinomycetes led to the identification of a large number of secondary metabolites. Morever, investigation of cytotoxic and antiviral activities of the extracts revealed that only three extracts exhibited antiviral activity and seven extracts exhibited cytotoxic activity.

Holospiniferoside: A New Antitumor Cerebroside from The Red Sea Cucumber Holothuria spinifera: In Vitro and In Silico Studies.

Chemical investigation of the methanolic extract of the Red Sea cucumber Holothuria spinifera led to the isolation of a new cerebroside, holospiniferoside (1), together with thymidine (2), methyl-α-d-glucopyranoside (3), a new triacylglycerol (4), and cholesterol (5). Their chemical structures were established by NMR and mass spectrometric analysis, including gas chromatography-mass spectrometry (GC-MS) and high-resolution mass spectrometry (HRMS). All the isolated compounds are reported in this species for the first time. Moreover, compound 1 exhibited promising in vitro antiproliferative effect on the human breast cancer cell line (MCF-7) with IC50 of 20.6 µM compared to the IC50 of 15.3 µM for the drug cisplatin. To predict the possible mechanism underlying the cytotoxicity of compound 1, a docking study was performed to elucidate its binding interactions with the active site of the protein Mdm2-p53. Compound 1 displayed an apoptotic activity via strong interaction with the active site of the target protein. This study highlights the importance of marine natural products in the design of new anticancer agents.

Potential Anticancer Lipoxygenase Inhibitors from the Red Sea-Derived Brown Algae Sargassum cinereum: An In-Silico-Supported In-Vitro Study.

LC-MS-assisted metabolomic profiling of the Red Sea-derived brown algae Sargassum cinereum "Sargassaceae" dereplicated eleven compounds 1-11. Further phytochemical investigation afforded two new aryl cresol 12-13, along with eight known compounds 14-21. Both new metabolites, along with 19, showed moderate in vitro antiproliferative activity against HepG2, MCF-7, and Caco-2. Pharmacophore-based virtual screening suggested both 5-LOX and 15-LOX as the most probable target linked to their observed antiproliferative activity. The in vitro enzyme assays revealed 12 and 13 were able to inhibit 5-LOX more preferentially than 15-LOX, while 19 showed a convergent inhibitory activity toward both enzymes. Further in-depth in silico investigation revealed the molecular interactions inside both enzymes' active sites and explained the varying inhibitory activity for 12 and 13 toward 5-LOX and 15-LOX.

Nano-Delivery Systems for Improving Therapeutic Efficiency of Dietary Polyphenols.

Dietary polyphenols, primarily categorized into flavonoids (flavanols, flavones, flavan-3-ols, anthocyanidins, flavanones, and isoflavones) and nonflavonoids (stilbenes and phenolic acids) are reported to have health-promoting effects, such as antioxidant, anti-inflammatory, antitumor, antibacterial, antiviral, and cardioprotective properties. However, their applications in functional food and medications are limited due to their low bioavailability and insufficient systemic delivery. Nano-delivery system conveyances frameworks astoundingly influence the take-up properties of the stacked atoms because the molecule small shape, size, and surface properties of the nanoparticles apply a vital role in the improvement of the systemic delivery of polyphenols This includes nano-emulsion, nano-encapsulation, polymer nanoparticles (NPs), nano-liposomes, solid liquid nanoparticles, cyclodextrins, and polyphenol-loaded hydrogels. Nano-technology is a rapidly developing area that guarantees the improvement of materials with novel measurements, new properties, and more extensive scope for utilization. This review reports the different therapeutic applications of dietary polyphenols, their biological activities, and different nano-delivery systems successfully developed for overcoming the delivery challenges. These applications also seek to improve their bioavailability, reduce toxicity, and enhance dietary polyphenol uptake across the gastrointestinal tract.