Plasma metabolomics analysis of endogenous and exogenous metabolites in the rat after administration of Lonicerae Japonicae Flos

A water-soluble preparation for intravenous administration of isorhamnetin and its pharmacokinetics in rats

Flavonoids are considered as health-protecting food constituents. The testing of their biological effects is however hampered by their low oral absorption and complex metabolism. In order to investigate the direct effect(s) of unmetabolized flavonoid, a preparation in a biologically friendly solvent for intravenous administration is needed. Isorhamnetin, a natural flavonoid and a human metabolite of the most frequently tested flavonoid quercetin, has very low water solubility (<3.5 μg/mL). The aim of this study was to improve its solubility to enable intravenous administration and to test its pharmacokinetics in an animal model. By using polyvinylpyrrolidone (PVP10) and benzalkonium chloride, we were able to improve the solubility approximately 600 times to 2.1 mg/mL. This solution was then administered intravenously at a dose of 0.5 mg/kg of isorhamnetin to rats and its pharmacokinetics was analyzed. The pharmacokinetics of isorhamnetin corresponded to two compartmental model with a rapid initial distribution phase (t1/2α: 5.7 ± 4.3 min) and a slower elimination phase (t1/2β: 61 ± 47.5 min). Two sulfate metabolites were also identified. PVP10 and benzalkonium did not modify the properties of isorhamnetin (iron chelation and reduction, and cell penetration) substantially. In conclusion, the novel preparation reported in this study is suitable for future testing of isorhamnetin effects under in vivo conditions.

Investigation of Lonicera japonica Flos against Nonalcoholic Fatty Liver Disease Using Network Integration and Experimental Validation

Background and objective: Lonicera japonica Flos (LJF) is a well-known traditional herbal medicine that has been used as an anti-inflammatory, antibacterial, antiviral, and antipyretic agent. The potent anti-inflammatory and other ethnopharmacological uses of LJF make it a potential medicine for the treatment of nonalcoholic fatty liver disease (NAFLD). This research is to explore the mechanisms involved in the activity of LJF against NAFLD using network integration and experimental pharmacology. Materials and methods: The possible targets of LJF involved in its activity against NAFLD were predicted by matching the targets of the active components in LJF with those targets involved in NAFLD. The analysis of the enrichment of GO functional annotations and KEGG pathways using Metascape, followed by constructing the network of active components–targets–pathways using Cytoscape, were carried out to predict the targets. Molecular docking studies were performed to further support the involvement of these targets in the activity of LJF against NAFLD. The shortlisted targets were confirmed via in vitro studies in an NAFLD cell model. Results: A total of 17 active components in LJF and 29 targets related to NAFLD were predicted by network pharmacology. Molecular docking studies of the main components and the key targets showed that isochlorogenic acid B can stably bind to TNF-α and CASP3. In vitro studies have shown that LJF down-regulated the TNF-α and CASP3 expression in an NAFLD cell model. Conclusions: These results provide scientific evidence for further investigations into the role of LJF in the treatment of NAFLD.

Dissection of the potential anti-influenza materials and mechanism of Lonicerae japonicae flos based on in vivo substances profiling and network pharmacology

Lonicerae japonicae flos.(LJF) was widely used as a drug to treat upper respiratory tract infection or a tea to clear heat in Asian countries for thousands of years. Despite of its curative effects confirmed by modern pharmacological methods, its functional materials and mechanism against influenza were still unclear and needed further investigation. In this study, an integrated strategy based on in vivo substances profiling and network pharmacology was proposed and applied to screen out the potential anti-influenza substances and mechanism of LJF. An UHPLC/Q-TOF MS method was utilized to profile the chemical components in LJF and their metabolites in rats. The targets of absorbed prototypes were predicted by Swiss Target Prediction, and they were further analyzed by String and Kyoto Encyclopedia of Genes and Genomes (KEGG). As a result, a total of 126 chemical components mainly featuring three chemical structure types were characterized, including 70 iridoid glycosides, 17 caffeoylquinic acids, 24 flavonoids, and 15 other types compounds. Among them, ten N-contained iridoid glycosides were characterized as potential novel compounds. Moreover, 141 xenobiotics (74 prototypes and 67 metabolites) were clearly screened out in rat plasma and urine after ingestion of LJF. Phase II reactions (sulfation, glucuronidation, methylation) and phase I reactions (dehydroxylation, hydrogenation, hydrolysis, N-heterocyclization) were the main metabolic reactions of LJF in rats. Further, a total of 338 targets were predicted and TNF, PTGS2 and EGFR were the three main targets involved in the pathology of influenza. In addition to normal NF-κB pathway, T cell signal pathway and mTOR signal pathway were the other patterns for LJF to achieve its anti-flu effects. Our work provided the meaningful data for further pharmacological validation of LJF against influenza, and a new strategy was also proposed for minimizing the process to reveal the mechanism and functional basis of TCMs.