Antiplatelet Effects of Flavonoid Aglycones Are Mediated by Activation of Cyclic Nucleotide-Dependent Protein Kinases.

Flavonoid aglycones are secondary plant metabolites that exhibit a broad spectrum of pharmacological activities, including anti-inflammatory, antioxidant, anticancer, and antiplatelet effects. However, the precise molecular mechanisms underlying their inhibitory effect on platelet activation remain poorly understood. In this study, we applied flow cytometry to analyze the effects of six flavonoid aglycones (luteolin, myricetin, quercetin, eriodictyol, kaempferol, and apigenin) on platelet activation, phosphatidylserine externalization, formation of reactive oxygen species, and intracellular esterase activity.

Thrombin-induced platelet inhibition by 2',4'-dihydroxychalcone and 2',4'-dihydroxydihydrochalcone is mediated by inhibition of ROS production and Thromboxane synthase a activity: structure-activity relationship of polyphenol secondary metabolites from .

In this study, we expanded our previous work by testing compounds for their ability to inhibit platelet activation at low (30 µM) concentration by inhibition of ROS production, thromboxane synthase (TxS) activity, and activation of cyclic nucleotide pathways. We also investigated whether some of these compounds could potentiate the effects of P2Y12 ADP receptor inhibitor action and discussed possible structure-activity relationships of the tested compounds. We showed that at this concentration only compounds and significantly inhibited thrombin-induced platelet activation which was accompanied by inhibition of ROS production and thromboxane synthase activity.

Polyacetylene Derivatives from the Polypore Fungus (Fistulina hepatica, Agaricomycetes) and Their Antimicrobial Activity.

Chemical investigation of the polypore fungus Fistulina hepatica resulted in the isolation of five compounds, including four new polyacetylenic fatty acid derivatives - isocinnatriacetin B (1), isocinnatriacetin A (2), cinna-triacetin C (3) and ethylcinnatriacetin A (4) together with one known polyacetylene fatty acid derivative - cinnatriacetin A (5). The structures were elucidated using spectroscopic methods (UV, NMR, HR-ESIMS) along with comparison to literature data. Antibacterial activity screening of compounds 1-5 against ESKAPE bacterial strains in vitro with zones of inhibition (ZOI) was performed and MIC values were established for the most active compounds (3 and 4).

Bracteatinine and isogroenlandicine, two new isoquinoline alkaloids isolated from Corydalis bracteata and their effect on platelet function.

Two previously undescribed isoquinoline alkaloids, bracteatinine (1) and isogroenlandicine (2), together with four known alkaloids - coptisine (3), dehydrocorydaline (4), palmatine (5) and jatrorrhizine (6) were isolated from the aerial parts of Corydalis bracteata (Steph. Ex. Willd.

New benzoquinone pigments from the hydnoid fungus and their biosynthetic relationship.

Chemical investigation of the hydnoid fungus resulted in the isolation of five compounds, including two new sarcodontic acid derivatives - setosic acid () and 7,8-dehydrohomosarcodontic acid () along with three known benzoquinone pigments - sarcodontic acid (), 4,5-dehydrosarcodontic acid () and dihydrosarcodontic acid (). The structures were elucidated using spectroscopic methods (UV, NMR and HR-ESIMS). The biosynthetic relationship of the isolated compounds is proposed and discussed.

The Ability of Acid-Based Natural Deep Eutectic Solvents to Co-Extract Elements from the Roots of L. and Associated Health Risks.

The roots of licorice ( L.) have been widely used in traditional and officinal medicines for the treatment of different diseases. Natural deep eutectic solvents (NADES) have become popular for the extraction of active principles from medicinal plants.

Phytochemical Characterization of Water Avens ( L.) Extracts: Structure Assignment and Biological Activity of the Major Phenolic Constituents.

Water avens ( L.) is a common plant widely spread in Europe and North America. It is rich in biologically active natural products, some of which are promising as prospective pharmaceuticals.

Isolation and Characterization of a New Flavone C-glycoside Isoembinin from Iris lacteal along with its Effects on Platelet Activation.

One new compound isoembinin 1 along with ten known compounds 2-11 were isolated from the terrestrial parts of Iris lactea Pall. All of the compound structures were determined through extensive 1D and 2D NMR experiments along with HR-ESIMS analysis and comparison with literature data. Because many flavonoids exert antiplatelet and antioxidant activity we tested the effects of the isolated flavone C-glycosides 1-9 on platelet activation and reactive oxygen species (ROS) production.

New cyclic diarylheptanoids from the false heartwood of Ehrh.

Two undescribed (- and five known cyclic diarylheptanoids (-) were isolated from the false heartwood of white birch ( Ehrh.). All structures were elucidated through extensive 1D and 2D NMR experiments and HR-ESI-MS data, along with comparison of their spectroscopic data with those reported in the literature.

A new dimethoxy dihydrochalcone isolated from the shoots of L.

A new dihydrochalcone, 2',4'-dimethoxydihydrochalcone (), together with 7 known compounds, 2',4'-dihydroxydihydrochalcone (), 2'-hydroxy-4'-methoxydihydrochalcone (), 2'-hydroxy-4'-methoxychalcone (), 1-(3,5-dihydroxy-4-methoxyphenyl)-2-(3-hydroxyphenyl) ethane (), 2,3,4,7-tetramethoxy-9,10-dihydrophenanthrene (), 5-hydroxy-2,3,4-trimethoxy-9,10-dihydrophenanthrene () and 5,7-dihydroxy-6,8-dimethyl flavanone () were isolated from the shoots of L. The structures of these compounds were elucidated using 1D and 2D NMR experiments along with HR-ESI-MS. Compound is reported for the genus for the first time.

Synthesis of N-succinyl- and N-glutaryl-chitosan derivatives and their antioxidant, antiplatelet, and anticoagulant activity.

The effects of temperature, reactant ratio, pH, and reaction time were studied on the polymers formed by the reactions of succinic and glutaric anhydrides with chitosan under both homogeneous and heterogeneous conditions. As a result, protocols were developed for the synthesis of succinyl- and glutaryl-chitosan derivatives (SC and GC, respectively) with a specific degree of substitution. The polymers were characterized by NMR spectroscopy, including two-dimensional NMR techniques, that confirms N-substitution of chitosan under reaction conditions used.