Two new phenylpropanoid glycosides from Lagotis brachystachya Maxim and their Xanthione Oxidase inhibitions

The hydroxytyrosol-typed phenylpropanoidglycosides: A phenylpropanoid glycoside family with significant biological activity

Hydroxytyrosol-typed phenylpropanoid glycosides (HPGs), composed of phenylethanol and various complex oligosaccharides, are widespread and abundant in different plant, and have a diverse range of biological activities. All HPGs reported previously have been isolated from natural sources, and most of them showed significant bioactivities, such as anti-inflamatory, anti-cancer, cytoprotection, neuro-protective effects, enzyme-inhibitory, anti-microbial effects, and cardiovascular activity. The goal of this review is to summarize the structures of HPGs reported over the past few decades, as well as to introduce their pharmacological effects. We also introduce the possible relationship between the structures of HPGs and their source plants, as well as the structure-activity relationships of some important activities. This review will serve as a resource for future research into this class of compounds, and demonstrate their potential value.

Evaluation of the anti-inflammatory material basis of Lagotis brachystachya in HepG2 and THP-1 cells

ETHNOPHARMACOLOGICAL RELEVANCE LAGOTIS BRACHYSTACHYA

Maxim is a traditional ethnic medicine commonly used in Tibet. In Tibetan medicine theory, Lagotis brachystachya is mainly used for the treatment of inflammatory related diseases. However, the active components and mechanism of the anti-inflammatory activity of Lagotis brachystachya are not clear.

AIM OF THE STUDY

The putative anti-inflammatory active compounds from Lagotis brachystachya Maxim and its anti-inflammation related mechanism involving in the TLR4/MyD88/NF-κB and NLRP3 signaling pathways were investigated.

MATERIALS AND METHODS

In this study, we investigated the anti-inflammatory activity and mechanism of 32 compounds extracted from Lagotis brachystachya in HepG2 and THP-1 cells using the alcohol-induced HepG2 cell injury model and the monosodium urate (MSU) combined with lipopolysaccharide (LPS)-induced THP-1 cell inflammation model.

RESULTS

The results found that six compounds, including Echinacoside, Quercetin, Homoplantaginin, Tricin-7-O-glucoside, Apigenin and Luteolin-7-O-beta-d-glucopyranoside, were shown to exhibit significant anti-inflammatory effects in both cell models. Furthermore, these compounds were shown to inhibit the TLR4/MyD88/NF-κB and NLRP3 signaling pathways and reduce the release of pro-inflammatory cytokines IL-1β, TNF-α, and IL-6 in both cell models.

CONCLUSION

These findings suggest that Echinacoside, Quercetin, Homoplantaginin, Tricin-7-O-glucoside, Apigenin and Luteolin-7-O-beta-d-glucopyranoside from Lagotis brachystachya have promising potential as natural anti-inflammatory agents for the treatment of inflammatory-related diseases. The discovery of bioactive compounds from this plant opens up possibilities for the development of novel treatments for inflammatory-related diseases, potentially providing alternative or adjunctive options to conventional therapies.

Antibacterial and antibiofilm activity of Lagotis brachystachya extract against extended-spectrum β-lactamases-producing Escherichia coli from broiler chickens

Lagotis brachystachya Maxim (L. brachystachya) is an herb widely used in traditional Tibetan medicine. In the present study, the antibacterial activity of L. brachystachya extract to extended-spectrum-lactamases (ESBLs)-producing E. coli was determined by Kirby-Bauer disc diffusion, minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) methods as well as time-kill curve assay. Meanwhile, the biofilm inhibition and eradication effects of L. brachystachya extract on the ESBLs-producing E. coli were evaluated by crystal violet staining, and further confirmed by confocal laser scanning microscope (CLSM) and scanning electron microscopy (SEM). The results indicated that L. brachystachya extract exhibited moderate antibacterial activity, with diameter of inhibition zones varying from 15.4 to 20.3 mm, and the MIC and MBC values were 6.25 to 25 mg/mL and 12.5 to 100 mg/mL, respectively. Time-kill curve showed that 4 × MIC level of L. brachystachya extract concentration of was able to kill 99.9% of ESBLs-producing E. coli after 16 h treatment. The biofilm inhibition rate and eradication rate for the ESBLs-producing E. coli were 35.66 to 79.91% and 22.18 to 56.21% at MIC level of extract concentration, respectively. CLSM images showed that the biofilm became thinner as the ESBLs-producing E. coli isolate exposed to L. brachystachya extract with a concentration-dependent manner from 1/4 × MIC to MIC compared with the control isolate. SEM images indicated that L. brachystachya extract at 1/2 × MIC and MIC levels could evidently inhibit the biofilm formation or eradicate the mature biofilms. The effect of L. brachystachya highlights its potential of antibacterial and antibiofilm activities against the ESBLs-producing E. coli.

Therapeutic potential of phenylethanoid glycosides: A systematic review

Phenylethanoid glycosides (PhGs) are generally water-soluble phenolic compounds that occur in many medicinal plants. Until June 2020, more than 572 PhGs have been isolated and identified. PhGs possess antibacterial, anticancer, antidiabetic, anti-inflammatory, antiobesity, antioxidant, antiviral, and neuroprotective properties. Despite these promising benefits, PhGs have failed to fulfill their therapeutic applications due to their poor bioavailability. The attempts to understand their metabolic pathways to improve their bioavailability are investigated. In this review article, we will first summarize the number of PhGs compounds which is not accurate in the literature. The latest information on the biological activities, structure-activity relationships, mechanisms, and especially the clinical applications of PhGs will be reviewed. The bioavailability of PhGs will be summarized and factors leading to the low bioavailability will be analyzed. Recent advances in methods such as bioenhancers and nanotechnology to improve the bioavailability of PhGs are also summarized. The existing scientific gaps of PhGs in knowledge are also discussed, highlighting research directions in the future.