Pharmacological Effects and Underlying Mechanisms of Licorice-Derived Flavonoids

Combining metabolomics and transcriptomics to reveal the potential medicinal value of rare species Glycyrrhiza squamulose

Licorice is a well-known Chinese medicinal plant that is widely used to treat multiple diseases and process food; however, wild licorice is now facing depletion. Therefore, there is an urgent need to identify and protect licorice germplasm diversity. In this study, metabolomic and transcriptomic analyses were conducted to investigate the biodiversity and potential medicinal value of the rare wild Glycyrrhiza squamulose. A total of 182 differentially accumulated metabolites and 395 differentially expressed genes were identified by comparing Glycyrrhiza uralensis and Glycyrrhiza squamulose. The molecular weights of the chemical component of G. squamulose were comparable with those of G. uralensis, suggesting that G. squamulose may have medicinal value. Differentially accumulated metabolites (DAMs), mainly flavonoids such as kaempferol-3-O-galactoside, kaempferol-3-O-(6"malonyl) glucoside, and hispidulin-7-O-glucoside, showed potential vitality in G. squamulose. Comparative transcriptomics with G. uralensis showed that among the 395 differentially expressed genes (DEGs), 69 were enriched in the isoflavonoid biosynthesis pathway. Multiomics analysis showed that the distinction in flavonoid biosynthesis between G. squamulose and G. uralensis was strongly associated with the expression levels of IF7GT and CYP93C. In addition to identifying similarities and differences between G. squamulose and G. uralensis, this study provides a theoretical basis to protect and investigate rare species such as G. squamulose.

Licochalcone A protects against LPS-induced inflammation and acute lung injury by directly binding with myeloid differentiation factor 2 (MD2)

BACKGROUND AND PURPOSE

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is a challenging clinical syndrome that leads to various respiratory sequelae and even high mortality in patients with severe disease. The novel pharmacological strategies and therapeutic drugs are urgently needed. Natural products have played a fundamental role and provided an abundant pool in drug discovery.

EXPERIMENTAL APPROACH

A compound library containing 160 natural products was used to screen potential anti-inflammatory compounds. Mice with LPS-induced ALI was then used to verify the preventive and therapeutic effects of the selected compounds.

KEY RESULTS

Licochalcone A was discovered from the anti-inflammatory screening of natural products in macrophages. A qPCR array validated the inflammation-regulatory effects of licochalcone A and indicated that the potential targets of licochalcone A may be the upstream proteins in LPS pro-inflammatory signalling. Further studies showed that licochalcone A directly binds to myeloid differentiation factor 2 (MD2), an assistant protein of toll-like receptor 4 (TLR4), to block both LPS-induced TRIF- and MYD88-dependent pathways. LEU61 and PHE151 in MD2 protein are the two key residues that contribute to the binding of MD2 to licochalcone A. In vivo, licochalcone A treatment alleviated ALI in LPS-challenged mice through significantly reducing immunocyte infiltration, suppressing activation of TLR4 pathway and inflammatory cytokine induction.

CONCLUSION AND IMPLICATIONS

In summary, our study identified MD2 as a direct target of licochalcone A for its anti-inflammatory activity and suggested that licochalcone A might serve as a novel MD2 inhibitor and a potential drug for developing ALI/ARDS therapy.

Licorice (Glycyrrhiza glabra L.)-Derived Phytochemicals Target Multiple Signaling Pathways to Confer Oncopreventive and Oncotherapeutic Effects

Cancer is a highly lethal disease, and its incidence has rapidly increased worldwide over the past few decades. Although chemotherapeutics and surgery are widely used in clinical settings, they are often insufficient to provide the cure for cancer patients. Hence, more effective treatment options are highly needed. Although licorice has been used as a medicinal herb since ancient times, the knowledge about molecular mechanisms behind its diverse bioactivities is still rather new. In this review article, different anticancer properties (antiproliferative, antiangiogenic, antimetastatic, antioxidant, and anti-inflammatory effects) of various bioactive constituents of licorice (Glycyrrhiza glabra L.) are thoroughly described. Multiple licorice constituents have been shown to bind to and inhibit the activities of various cellular targets, including B-cell lymphoma 2, cyclin-dependent kinase 2, phosphatidylinositol 3-kinase, c-Jun N-terminal kinases, mammalian target of rapamycin, nuclear factor-κB, signal transducer and activator of transcription 3, vascular endothelial growth factor, and matrix metalloproteinase-3, resulting in reduced carcinogenesis in several in vitro and in vivo models with no evident toxicity. Emerging evidence is bringing forth licorice as an anticancer agent as well as bottlenecks in its potential clinical application. It is expected that overcoming toxicity-related obstacles by using novel nanotechnological methods might importantly facilitate the use of anticancer properties of licorice-derived phytochemicals in the future. Therefore, anticancer studies with licorice components must be continued. Overall, licorice could be a natural alternative to the present medication for eradicating new emergent illnesses while having just minor side effects.

Slower progression of amyotrophic lateral sclerosis with external application of a Chinese herbal plaster–The randomized, placebo-controlled triple-blinded ALS-CHEPLA trial

Background

Amyotrophic lateral sclerosis (ALS) is a chronic neurodegenerative disease characterized by gradually increasing damage to the upper and lower motor neurons. However, definitive and efficacious treatment for ALS is not available, and oral intake in ALS patients with bulbar involvement is complicated due to swallowing difficulties.

Hypothesis/purpose

This study investigated whether the external plaster application of the herbal composition Ji-Wu-Li efficiently slows ALS progression because prior studies obtained promising evidence with oral herbal applications.

Study design

The randomized, triple-blinded study compared the efficacy, safety, and tolerability of the application of Ji-Wu-Li plaster (JWLP) with placebo plaster (PLAP).

Methods

In total, 120 patients with definite ALS, clinically probable ALS, or clinically probable laboratory-supported ALS were randomized in a 1:1 ratio to receive JWLP or PLAP. Patients were treated and observed for 20 weeks. The primary outcome was the ALSFRS-R score, while the secondary outcomes were the ALS-SSIT score and weight loss.

Results

The mean±SD decrease in the ALSFRS-R over 20 weeks differed by 0.84 points in a group comparison (JWLP, −4.44 ± 1.15; PLAP, −5.28 ± 1.98; p = 0.005). The mean increase in the ALS-SSIT over 20 weeks differed by 2.7 points in a group comparison (JWLP, 5.361.15; PLAP, 8.06 ± 1.72; p < 0.001). The mean weight loss over 20 weeks differed by 1.65 kg in a group comparison (JWLP, −3.98 ± 2.61; PLAP, −5.63 ± 3.17; p = 0.002). Local allergic dermatitis suspected as causal to the intervention occurred in 10 of 60 participants in the JWLP group and 9 of 60 participants in the PLAP group. Systemic adverse events were mild, temporary, and considered unrelated to the intervention.

Conclusion

The JWLP showed clinical efficacy in the progression of ALS, as measured by the ALSFRS-R, ALS-SSIT, and weight loss in a randomized, placebo-controlled trial. Because skin reactions occurred in both groups, the covering material needs improvement. All of the Ji Wu Li herbal ingredients regulate multiple mechanisms of neurodegeneration in ALS. Hence, JWLP may offer a promising and safe add-on therapy for ALS, particularly in patients with bulbar involvement, but a confirmative long-term multicentre study is required.

Isolation, Characterization, Pharmacology and Biopolymer Applications of Licorice Polysaccharides: Review

Licorice is known as "Gan-Cao" in traditional Chinese Medicine (TCM), belonging to the genus Glycyrrhiza (Family: Fabaceae/Leguminosae). It has a long medicinal history and wide applications in China. Polysaccharides of licorice (LPs) are one of the key bioactive components. As herbal polysaccharides attracted increasing interest in the past several decades, their extraction, isolation, structural characterization, pharmacological activities, and medicinal application have been explored extensively. It is worth heeding that the method of extraction and purification effects LPs, apart from specie and origin specificity. This review evaluates the method of extraction and purification and demonstrates its performance in gaining specific composition and its structure-activity relationship, which might lead the readers to a fresh horizon for developing advanced treatment strategies. It is recently reported that the conformation of LPs plays a vital role as biopolymers, such as selenized modification, microencapsulation, nanocomposite, liposome formulation, drug/hydrogel combinations, biosensor device, and synergistic effect with a vaccine. In addition, LPs showed a good thermodynamics profile, as these properties enable them to interact with additional supramolecular interaction by chemical modifications or copolymerization. Functional polymers that are responsive to various external stimuli, such as physical, chemical, and biological signals, are a promising study topic. Thus, LPs are emerging as a new biomaterial that can enhance intended formulation along exerting its inherent medicinal effects. It is hoped that this review will provide a basis for the utilization and further developments of licorice polysaccharides in the vast medium.

Mechanisms of Penetration Enhancement and Transport Utilizing Skin Keratine Liposomes for the Topical Delivery of Licochalcone A

Keratin liposomes have emerged as a useful topical drug delivery system given theirenhanced ability to penetrate the skin, making them ideal as topical drug vehicles. However, the mechanisms of the drug penetration enhancement of keratin liposomes have not been clearly elucidated. Therefore, licochalcone A(LA)-loaded skin keratin liposomes (LALs) were prepared to investigate their mechanisms of penetration enhancement on the skin and inB16F10 cells. Skin deposition studies, differential scanning calorimetry (DSC), attenuated total reflection-Fourier Transform Infrared Spectroscopy (ATR-FTIR), and skin distribution and intracellular distribution studies were carried out to demonstrate the drug enhancement mechanisms of LALs. We found that the optimal application of LALs enhanced drug permeation via alterations in the components, structure, and thermodynamic properties of the stratum corneum (SC), that is, by enhancing the lipid fluidization, altering the skin keratin, and changing the thermodynamic properties of the SC. Moreover, hair follicles were the main penetration pathways for the LA delivery, which occurred in a time-dependent manner. In the B16F10 cells, the skin keratin liposomes effectively delivered LA into the cytoplasm without cytotoxicity. Thus, LAL nanoparticles are promising topical drug delivery systems for pharmaceutical and cosmetic applications.