Project description:Background and Objective. Epimedium koreanum Nakai is a medicinal plant known for its health beneficial effects on impotence, arrhythmia, oxidation, aging, osteoporosis, and cardiovascular diseases. However, there is no report available that shows its effects on platelet functions. Here, we elucidated antiplatelet and antithrombotic effects of ethyl acetate fraction of E. koreanum. Methodology. We analyzed the antiplatelet properties using standard in vitro and in vivo techniques, such as light transmission aggregometry, scanning electron microscopy, intracellular calcium mobilization measurement, dense granule secretion, and flow cytometry to assess integrin α IIb β 3 activation, clot retraction, and Western blot, on washed platelets. The antithrombotic effects of E. koreanum were assessed by arteriovenous- (AV-) shunt model in rats, and its effects on hemostasis were analyzed by tail bleeding assay in mice. Key Results. E. koreanum inhibited platelet aggregation in agonist-stimulated human and rat washed platelets, and it also reduced calcium mobilization, ATP secretion, and TXB2 formation. Fibrinogen binding, fibronectin adhesion, and clot retraction by attenuated integrin α IIb β 3-mediated inside-out and outside-in signaling were also decreased. Reduced phosphorylation of extracellular signal-regulated kinases (ERK), Akt, PLCγ2, and Src was observed. Moreover, the fraction inhibited thrombosis. HPLC results revealed that the fraction predominantly contained icariin. Conclusion and Implications. E. koreanum inhibited platelet aggregation and thrombus formation by attenuating calcium mobilization, ATP secretion, TXB2 formation, and integrin α IIb β 3 activation. Therefore, it may be considered as a potential candidate to treat and prevent platelet-related cardiovascular disorders.
Project description:Ostericum koreanum Kitagawa is an important herbal medicine, whose taxonomic status has been changed to Angelica reflexa as a new species. This study generated the complete chloroplast genome sequence of O. koreanum, and reconsidered its molecular taxonomic status in Angelica by comparing it with related species. The length of the complete chloroplast genome was 147,282 bp, and there were four structures that included the large single copy region (93,185 bp), the small single copy region (17,663 bp) and the duplicated inverted regions (18,217 bp of each). Based on its phylogenetic trees, O. koreanum was grouped by high bootstrap value with the Angelica species. This result proved that O. koreanum is included in Angelica. Therefore, this chloroplast genome data generated for the first time a valuable genetic resource for the discrimination of herbal materials, phylogeny, and evolution.
Project description:The therapeutic properties of Epimediumkoreanum are presumed to be due to the flavonoid component icariin, which has been reported to have broad pharmacological potential and has demonstrated anti-diabetic, anti-Alzheimer's disease, anti-tumor, and hepatoprotective activities. Considering these therapeutic properties of icariin, its deglycosylated icaritin and glycosylated flavonoids (icaeriside II, epimedin A, epimedin B, and epimedin C) were evaluated for their ability to inhibit protein tyrosine phosphatase 1B (PTP1B) and ?-glucosidase. The results show that icaritin and icariside II exhibit potent inhibitory activities, with 50% inhibition concentration (IC50) values of 11.59 ± 1.39 ?M and 9.94 ± 0.15 ?M against PTP1B and 74.42 ± 0.01 and 106.59 ± 0.44 ?M against ?-glucosidase, respectively. With the exceptions of icaritin and icariside II, glycosylated flavonoids did not exhibit any inhibitory effects in the two assays. Enzyme kinetics analyses revealed that icaritin and icariside II demonstrated noncompetitive-type inhibition against PTP1B, with inhibition constant (Ki) values of 11.41 and 11.66 ?M, respectively. Moreover, molecular docking analysis confirmed that icaritin and icariside II both occupy the same site as allosteric ligand. Thus, the molecular docking simulation results were in close agreement with the experimental data with respect to inhibition activity. In conclusion, deglycosylated metabolites of icariin from E. koreanum might offer therapeutic potential for the treatment of type 2 diabetes mellitus.