Biotransformation of Platycosides, Saponins from Balloon Flower Root, into Bioactive Deglycosylated Platycosides

Coumarin Glycosides Reverse Enterococci-Facilitated Enteric Infections

Commensal enterococci with pathogenic potential often facilitate the growth of diverse pathogens, thereby exacerbating infections. However, there are few effective therapeutic strategies to prevent and intervene in enterococci-mediated polymicrobial infections. Here, we find that enterococci at high density drive the expansion and pathogenicity of enteric Salmonella enterica serotype Typhimurium (S. Tm). Subsequently, we show that the driving role of enterococci in such infections is counteracted by dietary coumarin glycosides in vivo. Enterococci, which are tolerant of iron-deficient environments, produce β-glucosidases to hydrolyze coumarin glycosides into bioactive aglycones, inhibiting S. Tm growth and ameliorating the severity of S. Tm-induced symptoms by inducing iron limitation. Overall, we demonstrate that coumarin glycosides as a common diet effectively reverse enterococci-facilitated enteric infections, providing an alternative intervention to combat polymicrobial infections.

Elucidating the anti-inflammatory activity of platycodins in lung inflammation through pulmonary distribution dynamics and grey relational analysis of cytokines

ETHNOPHARMACOLOGICAL RELEVANCE

Platycodonis Radix (PR) is a traditional herbal remedy used to prevent and treat lung inflammation, and platycodins are speculated to be the major active constituents. However, concrete experimental verification for this assertion remains absent thus far.

AIM OF THE STUDY

This study aims to compare the pulmonary distribution dynamics of five platycodins and analyze their effects on cytokines. Through the grey relational analysis (GRA) between pulmonary active components and cytokines, the study ascertains platycodins as the potential effective component against lung inflammation.

MATERIALS AND METHODS

A rat lung inflammation model was created using lipopolysaccharides (LPS). Pulmonary distribution dynamics were analyzed via LC-MS/MS. Cytokine changes and distribution patterns in lung tissues were studied by multi-factor reagent kit. GRA was applied to determine correlations between pulmonary components and cytokines. Finally, the anti-inflammatory properties of platycodins were further studied using LPS-induced BEAS-2B cells in vitro.

RESULTS

The results showed that five platycodins (Platycodin D, Platycodin D3, Deapio Platycodin D, 3-O-β-D-Glucopyranosyl Platycodigenin, and Platycodigenin) featured fast absorption rate, short time to peak, and slow metabolism rate. The pulmonary distribution dynamics were significantly affected within 2 h after LPS modeling. At the same time, PR altered the relationships among different cytokines induced by LPS stimulation, particularly inflammatory cytokines IL-6 and IFN-γ. The GRA results indicated good correlation between the pulmonary distribution dynamics of the five platycodins components and the changing patterns of cytokine levels, with Platycodin D3 contributing the most. Additionally, Platycodin D3 exhibited a protective role against LPS-induced inflammation by reducing the production of pro-inflammatory mediators such as IL-1β, IL-8, and ROS, as well as increasing the expression of the anti-inflammatory mediator IL-10.

CONCLUSIONS

Platycodins are the main anti-inflammatory agents in PR and there is a good correlation with cytokines. This contributes to the anti-pneumonia effect of PR.

Biotransformation of ginsenoside Rb1 and Rd to four rare ginsenosides and evaluation of their anti-melanogenic effects

Improving physiological activity of primary ginsenosides through biotransformation is of great significance for food applications. In this study, gynostapenoside XVII, gynostapenoside LXXV, ginsenoside F2, and ginsenoside CK were obtained by enzymolysis of an accessible extract composed of ginsenoside Rb1 and Rd. Their effects on melanin content and tyrosinase activity were compared in vitro, and molecular docking simulation was employed to elucidate the interaction between tyrosinase and individual saponin. The results indicated that four rare ginsenosides decreased tyrosinase activity, melanin content and microphthalmia-associated transcription factor (MITF) expression level, more greatly than their primary ginsenosides, and they were more readily to bind with ASP10 and GLY68 at active site of tyrosinase to inhibit tyrosinase activity as well. These findings suggested that the rare ginsenosides obtained by enzymolysis had excellent anti-melanogenic effect, which could expand the application of ginsenosides in the field of functional foods and health supplements.