Bioactivity and potential health benefits of licorice

Natural Products of Licorice for Uranium Decorporation with Low Toxicity and High Efficiency

The development and exploration of uranium decorporation agents with straightforward synthesis, high removal ability, and low toxicity are crucial guarantees for the safety of workers in the nuclear industry and the public. Herein, we report the use of traditional Chinese medicine licorice for uranium decorporation. Licorice has good adsorption performance and excellent selectivity for uranium in the simulated human environment. Glycyrrhizic acid (GL) has a high affinity for uranium (p(UO2) = 13.67) and will complex with uranium at the carbonyl site. Both licorice and GL exhibit lower cytotoxicity compared to the commercial clinical decorporation agent diethylenetriamine pentaacetate sodium salts (CaNa3-DTPA). Notably, at the cellular level, the uranium removal efficiency of GL is eight times higher than that of CaNa3-DTPA. Administration of GL by prophylactic intraperitoneal injection demonstrates that its uranium removal efficiency from kidneys and bones is 55.2 and 23.9%, while CaNa3-DTPA shows an insignificant effect. The density functional theory calculation of the bonding energy between GL and uranium demonstrates that GL exhibits a higher binding affinity (-2.01 vs -1.15 eV) to uranium compared to DTPA. These findings support the potential of licorice and its active ingredient, GL, as promising candidates for uranium decorporation agents.

Glycnsisitin A: A promising bicyclic peptide against heart failure that facilitates TFRC-mediated uptake of iron in cardiomyocytes

Zhigancao decoction is a traditional prescription for treating irregular pulse and palpitations in China. As the monarch drug of Zhigancao decoction, the bioactive molecules of licorice against heart diseases remain elusive. We established the HRESIMS-guided method leading to the isolation of three novel bicyclic peptides, glycnsisitins A-C (1-3), with distinctive C-C and C-O-C side-chain-to-side-chain linkages from the roots of Glycyrrhiza uralensis (Licorice). Glycnsisitin A demonstrated stronger cardioprotective activity than glycnsisitins B and C in an in vitro model of doxorubicin (DOX)-induced cardiomyocyte injury. Glycnsisitin A treatment not only reduced the mortality of heart failure (HF) mice in a dose-dependent manner but also significantly attenuated DOX-induced cardiac dysfunction and myocardial fibrosis. Gene set enrichment analysis (GSEA) of the differentially expressed genes indicated that the cardioprotective effect of glycnsisitin A was mainly attributed to its ability to maintain iron homeostasis in the myocardium. Mechanistically, glycnsisitin A interacted with transferrin and facilitated its binding to the transferrin receptor (TFRC), which caused increased uptake of iron in cardiomyocytes. These findings highlight the key role of bicyclic peptides as bioactive molecules of Zhigancao decoction for the treatment of HF, and glycnsisitin A constitutes a promising therapeutic agent for the treatment of HF.

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 induces mitochondria-dependent apoptosis and interacts with venetoclax in acute myeloid leukemia

The management of patients with acute myeloid leukemia (AML) remains a challenge because of the complexity and heterogeneity of this malignancy. Despite the recent approval of several novel targeted drugs, resistance seems inevitable, and clinical outcomes are still suboptimal. Increasing evidence supports the use of natural plants as an important source of anti-leukemic therapeutics. Licochalcone A (LCA) is an active flavonoid isolated from the roots of licorice, Glycyrrhiza uralensis Fisch., possessing extensive anti-tumor activities. However, its effects on AML and the underlying mechanisms remain unknown. Here, we showed that LCA decreased the viability of established human AML cell lines in a dose- and time-dependent manner. LCA significantly induced mitochondrial apoptotic cell death, accompanied by the downregulation of MCL-1, upregulation of BIM, truncation of BID, and cleavage of PARP. A prominent decline in the phosphorylation of multiple critical molecules, including AKT, glycogen synthase kinase-3β (GSK3β), ERK, and P38 was observed upon LCA treatment, indicating PI3K and MAPK signals were suppressed. Both transcription and translation of c-Myc were also inhibited by LCA. In addition, LCA enhanced the cytotoxicity of the BCL-2 inhibitor venetoclax. Furthermore, the anti-survival and pro-apoptotic effects were confirmed in primary blasts from 10 patients with de novo AML. Thus, our results expand the applications of LCA, which can be regarded as a valuable agent in treating AML.

Unveiling Anti-Diabetic Potential of Baicalin and Baicalein from Baikal Skullcap: LC-MS, In Silico, and In Vitro Studies

Type 2 diabetes mellitus (T2DM) is marked by persistent hyperglycemia, insulin resistance, and pancreatic β-cell dysfunction, imposing substantial health burdens and elevating the risk of systemic complications and cardiovascular diseases. While the pathogenesis of diabetes remains elusive, a cyclical relationship between insulin resistance and inflammation is acknowledged, wherein inflammation exacerbates insulin resistance, perpetuating a deleterious cycle. Consequently, anti-inflammatory interventions offer a therapeutic avenue for T2DM management. In this study, a herb called Baikal skullcap, renowned for its repertoire of bioactive compounds with anti-inflammatory potential, is posited as a promising source for novel T2DM therapeutic strategies. Our study probed the anti-diabetic properties of compounds from Baikal skullcap via network pharmacology, molecular docking, and cellular assays, concentrating on their dual modulatory effects on diabetes through Protein Tyrosine Phosphatase 1B (PTP1B) enzyme inhibition and anti-inflammatory actions. We identified the major compounds in Baikal skullcap using liquid chromatography-mass spectrometry (LC-MS), highlighting six flavonoids, including the well-studied baicalein, as potent inhibitors of PTP1B. Furthermore, cellular experiments revealed that baicalin and baicalein exhibited enhanced anti-inflammatory responses compared to the active constituents of licorice, a known anti-inflammatory agent in TCM. Our findings confirmed that baicalin and baicalein mitigate diabetes via two distinct pathways: PTP1B inhibition and anti-inflammatory effects. Additionally, we have identified six flavonoid molecules with substantial potential for drug development, thereby augmenting the T2DM pharmacotherapeutic arsenal and promoting the integration of herb-derived treatments into modern pharmacology.

Integrative metabolome and transcriptome analyses reveal the differences in flavonoid and terpenoid synthesis between Glycyrrhiza uralensis (licorice) leaves and roots

Licorice from Glycyrrhiza uralensis roots is used in foods and medicines. Although we are aware that licorice roots and leaves have distinct material compositions, the specific reasons for these differences remain unknown. Comparison of the metabolomes and transcriptomes between the leaves and roots revealed flavonoids and triterpenoid saponins were significantly different. Isoflavones were enriched in roots because of upregulation of genes encoding chalcone isomerase and flavone synthase, which are involved in isoflavone synthesis. Six triterpenoid saponins were significantly enriched only in the roots. The leaves did not accumulate glycyrrhetinic acid because of low expression levels of genes involved in its synthesis. A gene encoding a UDP glycosyltransferase, which likely catalyzes the key step in the transformation of glycyrrhetinic acid to glycyrrhizin, was screened. Our results provide information about the differences in flavonoid and triterpenoid synthesis between roots and leaves, and highlight targets for genetic engineering.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-023-01467-y.

Identification and quantification of compounds with Angiotensin-converting enzyme inhibitory activity in licorice by UPLC-MS

Licorice is a famous medicine-food herb for treating cardiovascular diseases in many compound prescriptions. Angiotensin-converting enzyme (ACE) is a key target of cardiovascular diseases. Despite its significance, there is limited scientific investigation regarding the ACE inhibitory effects of licorice. In this study, we used an activity-guided approach with an aggregation-induced emission (AIE) fluorescent probe to identify compounds with ACE-inhibitory activity in licorice. Nine components of licorice were found to have ACE inhibitory activity, in which 46 compounds were identified by using UPLC-QTOF-MS. Seven active compounds were found in this study. Among them, licochalcone B had best ACE inhibitory activity (IC50 = 0.24 μM). Finally, an UPLC-Q-MS method was established to quantify the five major active compounds in three batches of licorice. The findings of this study offer valuable insights into the potential of licorice as a source of ACE inhibitors and its relevance in the development of related products.

Microbial fortification of pharmacological metabolites in medicinal plants

Medicinal plants are rich in secondary metabolites with beneficial pharmacological effects. The production of plant secondary metabolites is subjected to the influences by environmental factors including the plant-associated microbiome, which is crucial to the host's fitness and survival. As a result, research interests are increasing in exploiting microbial capacities for enhancing plant production of pharmacological metabolites. A growing body of recent research provides accumulating evidence in support of developing microbe-based tools for achieving this objective. This mini review presents brief summaries of recent studies on medicinal plants that demonstrate microbe-augmented production of pharmacological terpenoids, polyphenols, and alkaloids, followed by discussions on some key questions beyond the promising observations. Explicit molecular insights into the underlying mechanisms will enhance microbial applications for metabolic fortification in medicinal plants.

Study on the effect of licochalcone A on intestinal flora in type 2 diabetes mellitus mice based on 16S rRNA technology

Licorice, has a long history in China where it has various uses, including as a medicine, and is often widely consumed as a food ingredient. Licorice is rich in various active components, including polysaccharides, triterpenoids, alkaloids, and nucleosides, among which licochalcone A (LicA) is an active component with multiple physiological effects. Previous studies from our research group have shown that LicA can significantly improve glucose and lipid metabolism and related complications in Type 2 diabetes mellitus (T2DM) mice. However, research on the mechanism of LicA in T2DM mice based on intestinal flora has not been carried out in depth. Therefore, in this study, LicA was taken as the research object and the effects of LicA on glucose and lipid metabolism and intestinal flora in T2DM mice induced by streptozotocin (STZ)/high-fat feed (HFD) were explored. The results indicated that LicA could reduce serum TC, TG, and LDL-C levels, increase HDL-C levels, reduce blood glucose, and improve insulin resistance and glucose tolerance. LicA also alleviated pathological damage to the liver. The results also showed that LicA significantly affected the intestinal microbiota composition and increased the α diversity index. β Diversity analysis showed that after the intervention of LicA, the composition of intestinal flora was significantly different from that in the T2DM model group. Correlation analysis showed that the changes in glucose and lipid metabolism parameters in mice were significantly correlated with the relative abundance of Firmicutes, Bacteroidetes, Helicobacter, and Lachnospiraceae (p < 0.01). Analysis of key bacteria showed that LicA could significantly promote the growth of beneficial bacteria, such as Bifidobacterium, Turicibacter, Blautia, and Faecococcus, and inhibit the growth of harmful bacteria, such as Enterococcus, Dorea, and Arachnococcus. In conclusion, it was confirmed that LicA reversed the imbalanced intestinal flora, and increased the richness and diversity of the species in T2DM mice.

Prevention of cleft lip and/or palate in A/J mice by licorice solution

Cleft lip and/or palate anomalies (CL ± P) are the most frequent birth defects affecting the orofacial region in humans. Although their etiology remains unclear, the involvement of environmental and genetic risk factors is known. This observational study aimed to investigate how the use of  crude drugs with estrogen activity influenced an animal model's ability to prevent CL ± P. A/J mice were randomly divided into six experimental groups. Five of these groups consumed a drink containing crude drug licorice root extract, with the following weights attributed to each group: 3 g in group I, 6 g in group II, 7.5 g in group III, 9 g in group IV, and 12 g in group V, whereas a control group consumed tap water. The effect of licorice extract was examined for fetal mortality and fetal orofacial cleft development compared to the control group. The rates for fetal mortality were 11.28%, 7.41%, 9.18%, 4.94%, and 7.90% in groups I, II, III, IV, and V, respectively, compared to 13.51% in the control group. There were no significant differences in the mean weight of alive fetuses in all five groups compared to the control group (0.63 ± 0.12). Group IV showed the lowest orafacial cleft occurrence of 3.20% (8 fetuses) with statistical significance (p = 0.0048) out of 268 live fetuses, whereas the control group had the occurrence of 8.75% (42 fetuses) among 480 live fetuses. Our study showed that the dried licorice root extract may reduce orofacial birth defects in experimental animal studies.

The preventive effect of Glycyrrhiza polysaccharide on lipopolysaccharide-induced acute colitis in mice by modulating gut microbial communities

Acute colitis is characterised by an unpredictable onset and causes intestinal flora imbalance together with microbial migration, which leads to complex parenteral diseases. Dexamethasone, a classic drug, has side effects, so it is necessary to use natural products without side effects to prevent enteritis. Glycyrrhiza polysaccharide (GPS) is an α-d-pyranoid polysaccharide with anti-inflammatory effects; however, its anti-inflammatory mechanism in the colon remains unknown. This study investigated whether GPS reduces the lipopolysaccharide (LPS)-induced inflammatory response in acute colitis. The results revealed that GPS attenuated the upregulation of tumour necrosis factor-α, interleukin (IL)-1β, and IL-6 in the serum and colon tissues and significantly reduced the malondialdehyde content in colon tissues. In addition, the 400 mg/kg GPS group showed higher relative expressions of occludin, claudin-1, and zona occludens-1 in colon tissues and lower concentrations of diamine oxidase, D-lactate, and endotoxin in the serum than the LPS group did, indicating that GPS improved the physical and chemical barrier functions of colon tissues. GPS increased the abundance of beneficial bacteria, such as Lactobacillus, Bacteroides, and Akkermansia, whereas pathogenic bacteria, such as Oscillospira and Ruminococcus were inhibited. Our findings indicate that GPS can effectively prevent LPS-induced acute colitis and exert beneficial effects on the intestinal health.

Comparative effectiveness of glycyrrhizic acid preparations aimed at improving liver function of patients with chronic hepatitis B: A network meta-analysis of 53 randomized controlled trials

BACKGROUND AND OBJECTIVES

Entecavir (ETV) has disadvantages, such as poor improvement in liver function, during the treatment of Chronic hepatitis B (CHB). Thus ETV is often used in clinical therapy with glycyrrhizic acid (GA) preparations. However, due to the lack of reliable and direct clinical studies, it remains controversial whether glycyrrhizic acid preparations have the best efficacy in CHB. Therefore, we aimed to compare and rank the different GA preparations in the treatment of CHB using network meta-analysis (NMA).

METHODS

We systematically searched MEDLINE, EMBASE, Cochrane Library, Web of Science, China national knowledge internet (CNKI), Wanfang, VIP, and SinoMed databases as of August 4, 2022. Literature was screened according to predefined inclusion and exclusion criteria to extract meaningful information. A Bayesian approach was used for random effects model network meta-analysis, and Stata 17 software was used for data analysis.

RESULTS

From 1074 papers, we included 53 relevant randomized clinical trials (RCTs). For the primary outcome, we used the overall effective rate in assessing the effectiveness of treatment for CHB (31 RCTs including 3007 patients): CGI, CGT, DGC and MgIGI significantly reduced the incidence of overall response compared to controls (RRs range from 1.16 to 1.24); SUCRA results showed that MgIGI was the best (SUCRA 0.923). In terms of secondary outcomes, we assessed the effect of treatment for CHB according to the level of reduction in ALT and AST: for ALT (37 RCTs including 3752 patients), CGI, CGT, DGC, DGI and MgIGI significantly improved liver function index compared to controls (MD range from 14.65 to 20.41); SUCRA results showed that CGI was the best (SUCRA 0.87); for AST, GI, CGT, DGC, DGI and MgIGI significantly improved liver function index compared to the control group (MD range from 17.46 to 24.42); SUCRA results showed that MgIGI was the best (SUCRA 0.871).

CONCLUSION

In this study, we verified that the combination of GA and Entecavir is more effective than entecavir monotherapy in the treatment of hepatitis B. MgIGI and CGI showed clinically significant effects on liver function recovery compared with other GA preparations. MgIGI appeared to be the best choice among all GA preparations for the treatment of CHB. Our study provides some references for the treatment of CHB.

Hydroalcoholic extract of Glycyrrhiza glabra root combined with Linum usitatissimum oil as an alternative for hormone replacement therapy in ovariectomized rats

Objective

Plant-derived estrogens (phytoestrogens) with structural similarity to primary female sex hormones could be suitable replacements for sex hormones. Therefore, the effects of the licorice root extract and Linum usitatissimum oil on biochemical and hormonal indices in the serum and uterine stereological changes in ovariectomized rats were evaluated.

Design

In this study, 70 adult female rats were randomly divided into seven groups including 1) control group, 2) sham-operated group, 3) ovariectomized (OVX) group, 4) OVX rats that received 1 mg/kg estradiol for 8 weeks at the day of post-operation, 5) OVX rats which received 2.0 mg/kg body wt Linum usitatissimum oil for 8 weeks at the day of post-operation, 6) OVX rats which received 2.0 mg/kg body wt licorice extract for 8 weeks at the day of post-operation, and 7) OVX rats which received 2.0 mg/kg body wt Linum usitatissimum oil + 2.0 mg/kg body wt licorice extract for 8 weeks at the day of post-operation. After eight weeks, alkaline phosphatase activity, as well as calcium, estradiol, and progesterone concentrations were assessed and tissue samples of the uterus were serologically examined.

Results

The results indicated that after 8 weeks of OVX the alkaline phosphatase activity (Mean = 637.7 IU/L) increased and the calcium (Mean = 7.09 mg/dl), estradiol (5.30 pmol/L), and progesterone (Mean = 3.53 nmol/L) reduced compared to other groups. Moreover, stereological changes in the uterus in ovariectomy groups were seen compared to the other groups. The treatment with Linum usitatissimum oil and licorice extract had a significant therapeutic effect on biochemical factors and stereological changes compared to the ovariectomized group.

Conclusion

The results of this study showed that the combination of Linum usitatissimum oil with licorice extract showed the high potential of hormone replacement therapy in the reduction of OVX complications.

Glycyrrhizae Radix suppresses lipopolysaccharide- and diazepam-induced nerve inflammation in the hippocampus, and contracts the duration of pentobarbital- induced loss of righting reflex in a mouse model

Nerve inflammation is linked to the development of various neurological disorders. This study aimed to examine whether Glycyrrhizae Radix effectively influences the duration of the pentobarbital-induced loss of righting reflex, which may increase in a mouse model of lipopolysaccharide (LPS)-induced nerve inflammation and diazepam-induced γ-aminobutyric acid receptor hypersensitivity. Furthermore, we examined the anti-inflammatory effects of Glycyrrhizae Radix extract on LPS-stimulated BV2 microglial cells, in vitro. Treatment with Glycyrrhizae Radix significantly decreased the duration of pentobarbital-induced loss of righting reflex in the mouse model. Furthermore, treatment with Glycyrrhizae Radix significantly attenuated the LPS-induced increases in interleukin-1β, interleukin-6, and tumor necrosis factor-alpha at the mRNA level, and it significantly reduced the number of ionized calcium-binding adapter molecule-1-positive cells in the hippocampal dentate gyrus 24 h after LPS treatment. Treatment with Glycyrrhizae Radix also suppressed the release of nitric oxide, interleukin-1β, interleukin-6, and tumor necrosis factor protein in culture supernatants of LPS-stimulated BV2 cells. In addition, glycyrrhizic acid and liquiritin, active ingredients of Glycyrrhizae Radix extract, reduced the duration of pentobarbital-induced loss of righting reflex. These findings suggest that Glycyrrhizae Radix, as well as its active ingredients, glycyrrhizic acid and liquiritin, may be effective therapeutic agents for the treatment of nerve inflammation-induced neurological disorders.

Multi-Omics Analysis Provides Crucial Insights into the Drought Adaptation of Glycyrrhiza uralensis Fisch

Drought adaptation of plants is closely related to resistance and tolerance to drought stress as well as the ability to recover after the elimination of the stress. Glycyrrhiza uralensis Fisch is a commonly applied herb whose growth and development are greatly affected by drought. Here, we provide the first comprehensive analysis of the transcriptomic, epigenetic, and metabolic responses of G. uralensis to drought stress and rewatering. The hyper-/hypomethylation of genes may lead to up-/downregulated gene expression, and epigenetic changes can be regarded as an important regulatory mechanism of G. uralensis under drought stress and rewatering. Moreover, integrated transcriptome and metabolome analysis revealed that genes and metabolites involved in pathways of antioxidation, osmoregulation, phenylpropanoid biosynthesis, and flavonoid biosynthesis may regulate the drought adaptation of G. uralensis. This work provides crucial insights into the drought adaptation of G. uralensis and offers epigenetic resources for cultivating G. uralensis with high drought adaptation.

Saponins of Selected Triterpenoids as Potential Therapeutic Agents: A Review

Saponins represent important natural derivatives of plant triterpenoids that are secondary plant metabolites. Saponins, also named glycoconjugates, are available both as natural and synthetic products. This review is focused on saponins of the oleanane, ursane, and lupane types of triterpenoids that include several plant triterpenoids displaying various important pharmacological effects. Additional convenient structural modifications of naturally-occurring plant products often result in enhancing the pharmacological effects of the parent natural structures. This is an important objective for all semisynthetic modifications of the reviewed plant products, and it is included in this review paper as well. The period covered by this review (2019–2022) is relatively short, mainly due to the existence of previously published review papers in recent years.

A review on the plant resources of important medicinal licorice

ETHNOPHARMACOLOGICAL RELEVANCE

Glycyrrizae Radix et Rhizoma has various effects, including tonifying the spleen and qi, clearing heat and toxic substances, eliminating phlegm, relieving cough and pain, and harmonizing the effects of other medicines. It is widely used in the pharmaceutical and food industries.

AIMS OF THE STUDY

This review systematically collates the identification of Glycyrrhiza Linn. species with medicinal value and their distributions. The morphological and genetic characteristics, distribution, quantity of reserves in China, suitable environment, and area of suitable habitat of important medicinal species were reviewed. The effects of the natural environment and cultivation management (water and nutrients) on the growth and quality of licorice were reviewed. The aim is to make people have a systematic understanding of the status of medicinal plant resources of the G. Linn., and understand the natural and human factors that affect its quality, so as to provide help for the collection of resources of the important medicinal licorice and the human control of its quality in the future.

MATERIALS AND METHODS

We conducted extensive searches of the primary literature, master's and doctoral theses, and pharmacopeias of many countries using PubMed, Geenmedical, CNKI, Web of Science, SCI-hub and other databases. The keywords used in searches included "classification of Glycyrrhiza," "medicinal Glycyrrhiza," "distribution of Glycyrrhiza," and "suitable environment for Glycyrrhiza" The results of research conducted by our research group on the morphological and genetic characteristics, natural distribution, and effects of artificial regulation on the growth and quality of licorice were summarized.

RESULTS

There are approximately 29 species of G. Linn. worldwide, including 15 species with medicinal value. These species occur on all continents except Antarctica across 41 countries. Only one licorice is recorded in Indian pharmacopoia,two species are recorded in US and Japanese pharmacopoeias,and three species are recorded in most national pharmacopoeias: G. glabra Linn., G. uralensis Fisch. and G. inflata Batalin. These three medicinal licorice species are mainly distributed in Eurasia, especially Central Asia. The main morphological differences between these three medicinal licorice species are in the leaves, inflorescences, pods, and seeds, and they can be distinguished by ITS and psbA-trnH sequences. The reserves of wild licorice in China have decreased annually to 1.04 million(t) in 2010. The cultivation area of G. uralensis Fisch in China is currently approximately 26,900 hm². Soil conditions have a substantial effect on the yield and quality of G. uralensis Fisch, especially water and nutrients. Appropriate irrigation and fertilization measures can enhance the quality of G. uralensis Fisch.

CONCLUSIONS

G. Linn. species and their natural distributions were summarized. The morphology, genetic characteristics, suitable environment, and area of suitable habitat of three medicinal licorice species collected in major countries were described. The main environmental conditions and cultivation measures affecting their growth and medicinal quality were determined. This article provides a comprehensive review on G. Linn. medicinal plant resources to enhance the future use of these resources.

Potential of glycyrrhizic and glycyrrhetinic acids against influenza type A and B viruses: A perspective to develop new anti-influenza compounds and drug delivery systems

Despite the recent dynamic development of medicine, influenza is still a significant epidemiological problem for people around the world. The growing resistance of influenza viruses to currently available antiviral drugs makes it necessary to search for new compounds or drug forms with potential high efficacy against human influenza A and B viruses. One of the methods of obtaining new active compounds is to chemically modify privileged structures occurring in the natural environment. The second solution, that is gaining more and more interest, is the use of modern drug carriers, which significantly improve physicochemical and pharmacokinetic parameters of the transported substances. Molecules known from the earliest times for their numerous therapeutic properties are glycyrrhizinic acid (GA) and glycyrrhetinic acid (GE). Both compounds constitute the main active agents of the licorice (Glycyrrhiza glabra, Leguminosae) root and, according to a number of scientific reports, show antiviral properties against both DNA and RNA viruses. The above information prompted many scientific teams around the world to obtain and test in vitro and/or in vivo new synthetic GA and GE derivatives against influenza A and B viruses. Similarly, in recent years, a significant amount of GA and GE-based drug delivery systems (DDS) such as nanoparticles, micelles, liposomes, nanocrystals, and carbon dots has been prepared and tested for antiviral activity, including those against influenza A and B viruses. This work systematizes the attempts undertaken to study the antiviral activity of new GA and GE analogs and modern DDS against clinically significant human influenza viruses, at the same time indicating the directions of their further development.

HPLC analysis of ammonium glycyrrhizate listed in the European, United States, and Japanese Pharmacopoeias under reported and modified conditions: revision of the peak assignment for 18α-glycyrrhizin in the European and United States Pharmacopoeias

We examined ammonium glycyrrhizate listed in the monographs of the European Pharmacopoeia (EP) and United States Pharmacopoeia (USP) as well as in the reagents and solutions used in the general test of the Japanese Pharmacopoeia by performing HPLC on their sample standards or reference reagents under reported and modified conditions. Comparative experiments involving five authentic samples, namely, 18β-glycyrrhizin (1), 18α-glycyrrhizin (2), licorice-saponin G2 (3), licorice-saponin H2 (4), and galacturonic acid-replaced glycyrrhizin (the 4″-epimer of 18β-glycyrrhizin) (5), led us to propose the revision of the peak assignment of 18α-glycyrrhizin (2) and postscript a possible co-existence of galacturonic acid-replaced glycyrrhizin (5) as a hidden component in the EP and USP. We also proposed that the α-configuration used in the nomenclature of the glycosidic bond between aglycone and the sugar units of ammonium glycyrrhizate and impurities in the EP and USP should be revised to the β-configuration.

Silver Nanoparticles and Glycyrrhiza glabra (Licorice) Root Extract as Modifying Agents of Hydrogels Designed as Innovative Dressings

The interest in the application of plant extracts as modifiers of polymers intended for biomedical purposes is constantly increasing. The therapeutical properties of the licorice root, including its anti-inflammatory and antibacterial activity, make this plant particularly promising. The same applies to silver nanoparticles showing antibacterial properties. Thus the main purpose of the research was to design hydrogel dressings containing both licorice root extract and nanosilver so as to obtain a system promoting wound regeneration processes by preventing infection and inflammation within the wound. The first step included the preparation of the plant extract via the solid-liquid extraction using the Soxhlet extractor and the synthesis of silver nanoparticles by the chemical reduction of silver ions using a sodium borohydride as a reducing agent. Subsequently, hydrogels were synthesized via photopolymerization and subjected to studies aiming at characterizing their sorption properties, surface morphology via scanning electron microscopy, and their impact on simulated physiological liquids supported by defining these liquids' influence on hydrogels' structures by FT-IR spectroscopy. Next, the tensile strength of hydrogels and their percentage elongation were determined. Performed studies also allowed for determining the hydrogels' wettability and free surface energies. Finally, the cytotoxicity of hydrogels towards L929 murine fibroblasts via the MTT reduction assay was also verified. It was demonstrated that developed materials showed stability in simulated physiological liquids. Moreover, hydrogels were characterized by high elasticity (percentage elongation within the range of 24-29%), and their surfaces were hydrophilic (wetting angles below 90°). Hydrogels containing both licorice extract and nanosilver showed smooth and homogeneous surfaces. Importantly, cytotoxic properties towards L929 murine fibroblasts were excluded; thus, developed materials seem to have great potential for application as innovative dressings.

Saponin Biosynthesis in Pulses

Pulses are a group of leguminous crops that are harvested solely for their dry seeds. As the demand for plant-based proteins grows, pulses are becoming important food crops worldwide. In addition to being a rich source of nutrients, pulses also contain saponins that are traditionally considered anti-nutrients, and impart bitterness and astringency. Saponins are plant secondary metabolites with great structural and functional diversity. Given their diverse functional properties and biological activities, both undesirable and beneficial, saponins have received growing attention. It can be expected that redirecting metabolic fluxes to control the saponin levels and produce desired saponins would be an effective approach to improve the nutritional and sensory quality of the pulses. However, little effort has been made toward understanding saponin biosynthesis in pulses, and, thus there exist sizable knowledge gaps regarding its pathway and regulatory network. In this paper, we summarize the research progress made on saponin biosynthesis in pulses. Additionally, phylogenetic relationships of putative biosynthetic enzymes among multiple pulse species provide a glimpse of the evolutionary routes and functional diversification of saponin biosynthetic enzymes. The review will help us to advance our understanding of saponin biosynthesis and aid in the development of molecular and biotechnological tools for the systematic optimization of metabolic fluxes, in order to produce the desired saponins in pulses.

Amelioration of Brain Damage after Treatment with the Methanolic Extract of Glycyrrhizae Radix et Rhizoma in Mice

Glycyrrhizae Radix et Rhizoma (GR) is a traditional herbal medicine widely used in Asian countries. GR was the most frequently used medicine among stroke patients in Donguibogam, the most representative book in Korean medicine. In the present study, we investigated the neuroprotective effects of the GR methanolic extract (GRex) on an ischemic stroke mice model. Ischemic stroke was induced by a 90 min transient middle cerebral artery occlusion (MCAO), and GRex was administered to mice with oral gavage after reperfusion of MCA blood flow. The MCAO-induced edema and infarction volume was measured, and behavioral changes were evaluated by a novel object recognition test (NORT). Immunofluorescence stains and Western blotting identified underlying mechanisms of the protective effects of GRex. GRex post-treatment in mice with MCAO showed potent effects in reducing cerebral edema and infarction at 125 mg/kg but no effects when the dosage was much lower or higher than 125 mg/kg. GRex inhibited the decrease of spontaneous motor activity and novel object recognition functions. The neuroprotective effects of GRex on ischemic stroke were due to its regulation of inflammation-related neuronal cells, such as microglia and astrocytes.

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.

Development of Highly Sensitive Chemiluminescence Enzyme Immunostaining Assay to Determine Glycyrrhizin Content Using Anti-glycyrrhizin Monoclonal Antibody

Licorice, the root of Glycyrrhiza spp., is used in a large number of herbal medicines, such as traditional Chinese medicines, Japanese Kampo medicines, and therapeutic drugs. Since glycyrrhizin (GL) is among the main components in licorice and exhibits numerous beneficial pharmacological activities, the content of GL directly affects biological activity. The quality control based on GL content is an important factor in ensuring biological activity; however, the content of GL in licorice varies depending on plant cultivation environment, genetic factors, and species type. Previously, we prepared an anti-GL monoclonal antibody (anti-GL mAb) and employed it in various immunochemical assays for quality control of licorice and licorice-based products. In this study, we employed the anti-GL mAb in chemiluminescence enzyme immunostaining (CLEIS) to develop a very simple, rapid, specific, and sensitive quality control assay for licorice products, with a limit of detection of 3.9 ng. Furthermore, the CLEIS assay enabled semiquantitative analysis of GL in Kampo medicines. Our results showed that multiple samples can be simultaneously analyzed using CLEIS, and it is a useful tool for determining GL content, as well as ensuring chemical quality control of licorice-containing products and herbal medicines.

Multi-omics profiling reveals comprehensive microbe-plant-metabolite regulation patterns for medicinal plant Glycyrrhiza uralensis Fisch

Glycyrrhiza uralensis Fisch is a medicinal plant widely used to treat multiple diseases in Europe and Asia, and its efficacy largely depends on liquiritin and glycyrrhizic acid. The regulatory pattern responsible for the difference in efficacy between wild and cultivated G. uralensis remains largely undetermined. Here, we collected roots and rhizosphere soils from wild (WT) G. uralensis as well as those farmed for 1 year (C1) and 3 years (C3), generated metabolite and transcript data for roots, microbiota data for rhizospheres and conducted comprehensive multi-omics analyses. We updated gene structures for all 40 091 genes in G. uralensis, and based on 52 differentially expressed genes, we charted the route-map of both liquiritin and glycyrrhizic acid biosynthesis, with genes BAS, CYP72A154 and CYP88D6 critical for glycyrrhizic acid biosynthesis being significantly expressed higher in wild G. uralensis than in cultivated G. uralensis. Additionally, multi-omics network analysis identified that Lysobacter was strongly associated with CYP72A154, which was required for glycyrrhizic acid biosynthesis. Finally, we developed a holistic multi-omics regulation model that confirmed the importance of rhizosphere microbial community structure in liquiritin accumulation. This study thoroughly decoded the key regulatory mechanisms of liquiritin and glycyrrhizic acid, and provided new insights into the interactions of the plant's key metabolites with its transcriptome, rhizosphere microbes and environment, which would guide future cultivation of G. uralensis.

In Vitro Antimelanoma Properties of Verbena officinalis Fractions

Verbena officinalis is commonly used in traditional medicine to treat many ailments. Extracts of this plant are therapeutic agents for the potential treatment of different diseases, including colorectal and liver cancers, but have not been explored for their anti-melanoma potential so far. The goal of the current work was to prepare a methanolic extract and fractionate it using hexane, chloroform, ethyl acetate, butanol, and acetone to get semi-purified products. These semi-purified fractions were studied for their potency against melanoma cell lines. The three potent fractions (HA, VO79, and EA3) demonstrated 50% inhibition concentration (IC₅₀) values as low as 2.85 µg/mL against the LOX IMVI cell line. All three fractions showed similar potency in inhibiting the growth of the B16 cells, a murine melanoma cell line. Based on high-resolution mass spectrometry (HRMS) data, for the first time, we report on lupulone A from this plant. LC-MS data also indicated the presence of hedergonic acid, serjanic acid, and other compounds in V. officinalis extracts.

Effect of Chinese Herbs on Serum Biochemical Parameters, Immunity Indices, Antioxidant Capacity and Metabolomics in Early Weaned Yak Calves

Chinese traditional herbs are used widely as feed supplements to improve the immune response and antioxidant capacity of livestock. Twenty early-weaned 4-month-old yak calves (72.3 ± 3.65 kg) were divided randomly into four groups (n = 5 per group); three groups were provided with supplementary 80 mL/kg DMI of the root water extracts of either Angelica sinensis, Codonopsis pilosula or Glycyrrhiza uralensis, and one group (control) was not provided with a supplement. Compared to control calves, calves consuming the three herbal extracts increased serum concentrations of albumin (ALB) and glutathione peroxidase (GSH-Px), but decreased serum concentrations of free fatty acids (FFAs) and malondialdehyde (MDA) (p < 0.05). Calves consuming A. sinensis decreased (p < 0.05) serum concentration of total cholesterol (TC), and increased (p < 0.05) serum concentration of total proteins (TP). Serum FFA concentrations increased (p = 0.004) linearly with time in the control group, but not in the groups consuming herbs. Serum metabolomic data demonstrated that A. sinensis and C. pilosula regulate mainly amino acid metabolism, while G. uralensis regulates mainly carbon and amino acid metabolism. It was concluded that the three herbal root extracts, as dietary supplements, improved energy and nitrogen metabolism, and enhanced the antioxidant capacity of yak calves.

Regulation of the Keap1-Nrf2 Signaling Axis by Glycyrrhetinic Acid Promoted Oxidative Stress-Induced H9C2 Cell Apoptosis

Excessive reactive oxygen species (ROS) could interfere with the physiological capacities of H₉C₂ cells and cause cardiomyocyte apoptosis. Glycyrrhetinic acid (GA), one of the main medicinal component of Glycyrrhetinic Radix et Rhizoma, shows toxic and adverse side effects in the clinic setting. In particular, some studies have reported that GA exerts toxic effects on H₉C₂ cells. The purpose of this study is to assess the effect of GA-induced oxidative stress on cultured H₉C₂ cells and reveal the relevant signaling pathways. LDH assay was used to assess cell damage. Apoptosis was detected using Hoechst 33242 and a propidium iodide (PI) assay. An Annexin V-fluorescein isothiocyanate/PI double-staining assay was utilized to investigate GA-induced apoptosis in H₉C₂ cells. The expression level of specific genes/proteins was evaluated by RT-qPCR and Western blotting. Flow cytometry and DCFH-DA fluorescent testing were used to determine the ROS levels of H₉C₂ cells. The potential mechanism of GA-induced cardiomyocyte injury was also investigated. GA treatment increased ROS generation and mitochondrial membrane depolarization and triggered caspase-3/9 activation and apoptosis. GA treatment also caused the nuclear translocation of NF-E2-related factor 2 after its dissociation from Keap1. This change was accompanied by a dose-dependent decline in the expression of the downstream target gene heme oxygenase-1. The findings demonstrated that GA could regulate the Keap1-Nrf2 signaling axis and induce oxidative stress to promote the apoptosis of H₉C₂ cells.

Atheroprotective Effects of Glycyrrhiza glabra L

Cardiovascular diseases associated with atherosclerosis are the major cause of death in developed countries. Early prevention and treatment of atherosclerosis are considered to be an important aspect of the therapy of cardiovascular disease. Preparations based on natural products affect the main pathogenetic steps of atherogenesis, and so represent a perspective for the long-term prevention of atherosclerosis development. Numerous experimental and clinical studies have demonstrated the multiple beneficial effects of licorice and its bioactive compounds—anti-inflammatory, anti-cytokine, antioxidant, anti-atherogenic, and anti-platelet action—which allow us to consider licorice as a promising atheroprotective agent. In this review, we summarized the current knowledge on the licorice anti-atherosclerotic mechanisms of action based on the results of experimental studies, including the results of the in vitro study demonstrating licorice effect on the ability of blood serum to reduce intracellular cholesterol accumulation in cultured macrophages, and presented the results of clinical studies confirming the ameliorating activity of licorice in regard to traditional cardiovascular risk factors as well as the direct anti-atherosclerotic effect of licorice.

Identification of the high-yield monacolin K strain from Monascus spp. and its submerged fermentation using different medicinal plants

BACKGROUND

Medical plants confer various benefits to human health and their bioconversion through microbial fermentation can increase efficacy, reduce toxicity, conserve resources and produce new chemical components. In this study, the cholesterol-lowering monacolin K genes and content produced by Monascus species were identified. The high-yield monacolin K strain further fermented with various medicinal plants. The antioxidant and anti-inflammatory activities, red pigment and monacolin K content, total phenolic content, and metabolites in the fermented products were analyzed.

RESULTS

Monacolin K was detected in Monascus pilosus (BCRC 38072), and Monascus ruber (BCRC 31533, 31523, 31534, 31535, and 33323). It responded to the highly homologous mokA and mokE genes encoding polyketide synthase and dehydrogenase. The high-yield monacolin K strain, M. ruber BCRC 31535, was used for fermentation with various medicinal plants. A positive relationship between the antioxidant capacity and total phenol content of the fermented products was observed after 60 days of fermentation, and both declined after 120 days of fermentation. By contrast, red pigment and monacolin K accumulated over time during fermentation, and the highest monacolin K content was observed in the fermentation of Glycyrrhiza uralensis, as confirmed by RT-qPCR. Moreover, Monascus-fermented medicinal plants including Paeonia lactiflora, Alpinia oxyphylla, G. uralensis, and rice were not cytotoxic. Only the product of Monascus-fermented G. uralensis significantly exhibited the anti-inflammatory capacity in a dose-dependent manner in lipopolysaccharide-induced Raw264.7 cells. The metabolites of G. uralensis with and without fermentation (60 days) were compared by LC/MS. 2,3-Dihydroxybenzoic acid, 3,4-dihydroxyphenylglycol, and 3-amino-4-hydroxybenzoate were considered to enhance the antioxidant and anti-inflammatory ability.

CONCLUSIONS

Given that highly homologous monacolin K and citrinin genes can be observed in Monascus spp., monacolin K produced by Monascus species without citrinin genes can be detected through the complementary methods of PCR and HPLC. In addition, the optimal fermentation time was important to the acquisition of antioxidants, red pigment and monacolin K. These bioactive substances were significantly affected by medicinal plants over fermentation time. Consequently, Monascus-fermented G. uralensis had a broad spectrum of biological activities.

Molecular dissection of genes and promoters involved in glycyrrhizin biosynthesis revealed phytohormone induced modulation in Glycyrrhiza glabra L

The study reports cloning and characterization of complete biosynthetic gene cluster committed to glycyrrhizin biosynthesis along with their corresponding promoter regions from Glycyrrhiza glabra. The identified genes namely, β-amyrin synthase, β-amyrin-11-oxidase, 11-oxo-beta-amyrin 30-oxidase and UDP-dependent glucosyltransferase, were hetrologously expressed in Nicotiana benthamiana for functional validation. The phyto-hormone, naphthalene acetic acid was shown to prompt maximum up regulation (1.3-14.0 folds) of all the genes, followed by gibberellic acid (0.001-10.0 folds) and abscisic acid (0.2-7.7 folds) treatments. The promoter-GUS fusion constructs infiltrated leaves of the identified genes exhibited enhanced promoter activity of β-amyrin synthase (3.9 & 3.0 folds) and 11-oxo-beta-amyrin 30-oxidase (3.6 & 3.2 folds) under the GA₃ and NAA treatments, respectively as compared to their respective untreated controls. The transcriptional control of the three phytohormones studied could be correlated to the cis-responsive elements present in the upstream regions of the individual genes. The study provided an insight into the intricate interaction between hormone-responsive motifs with the corresponding co-expression of the glycyrrhizin biosynthetic pathway genes. The study will help in understanding the phytohormones-mediated regulation of glycyrrhizin biosynthesis and its modulation in the plant.

GuRhaGT, a highly specific saponin 2''-O-rhamnosyltransferase from Glycyrrhiza uralensis

A highly regio- and donor-specific 2''-O-rhamnosyltransferase GuRhaGT was characterised from the medicinal plant Glycyrrhiza uralensis. GuRhaGT could efficiently catalyse rhamnosylation at 2''-OH of the C-3 glycosyl moiety of triterpenoid saponins.

Liquiritigenin Inhibits Lipid Accumulation in 3T3-L1 Cells via mTOR-Mediated Regulation of the Autophagy Mechanism

Liquiritigenin (LQG) is a natural flavonoid from the herb Glycyrrhiza uralensis Fisch that exhibits multiple biological activities. However, its specific role in antiobesity and its related underlying molecular mechanisms remain unknown. The primary purpose of this study is to explore the effects and regulatory mechanisms of LQG on lipid accumulation in 3T3-L1 adipocytes. The results show that LQG significantly reduced triglyceride levels and downregulated the expression of transcription factors such as CCAAT/enhancer-binding protein α (C/EBPα) and peroxisome proliferator-activated receptor γ (PPARγ) in 3T3-L1 adipocytes. Additionally, the expression of sterol-regulatory element-binding protein 1c (SREBP1c), acetyl-CoA carboxylase 1 (ACC1), and fatty acid synthase (FASN) involved in lipogenesis was reduced by treatment with LQG. The protein expression levels of light chain 3B (LC3B), autophagy-related protein 7 (ATG7) and p62 were also modulated by LQG, leading to the suppression of autophagy. Further, LQG activated the phosphorylation of the mammalian target of rapamycin (mTOR), the inhibition of which was followed by the restored expression of autophagy-related proteins. Pretreatment with an mTOR inhibitor also reverted the expression of several genes or proteins involved in lipid synthesis. These results suggest that LQG inhibited lipid accumulation via mTOR-mediated autophagy in 3T3-L1 white adipocytes, indicating the role of LQG as a potential natural bioactive component for use in dietary supplements for preventing obesity.

Assessment of Herb-Drug Interaction Potential of Five Common Species of Licorice and Their Phytochemical Constituents

The dried roots and rhizomes of Glycyrrhiza species (G. glabra, G. uralensis and G. inflata), commonly known as licorice, have long been used in traditional medicine. In addition, two other species, G. echinata and G. lepidota are also considered "licorice" in select markets. Currently, licorice is an integral part of several botanical drugs and dietary supplements. To probe the botanicals' safety, herb-drug interaction potential of the hydroethanolic extracts of five Glycyrrhiza species and their key constituents was investigated by determining their effects on pregnane X receptor, aryl hydrocarbon receptor, two major cytochrome P450 isoforms (CYP3A4 and CYP1A2), and the metabolic clearance of antiviral drugs. All extracts enhanced transcriptional activity of PXR and AhR (>2-fold) and increased the enzyme activity of CYP3A4 and CYP1A2. The highest increase in CYP3A4 was seen with G. echinata (4-fold), and the highest increase in CYP1A2 was seen with G. uralensis (18-fold) and G. inflata (16-fold). Among the constituents, glabridin, licoisoflavone A, glyasperin C, and glycycoumarin activated PXR and AhR, glabridin being the most effective (6- and 27-fold increase, respectively). Licoisoflavone A, glyasperin C, and glycycoumarin increased CYP3A4 activity while glabridin, glyasperin C, glycycoumarin, and formononetin increased CYP1A2 activity (>2-fold). The metabolism of antiretroviral drugs (rilpivirine and dolutegravir) was increased by G. uralensis (2.0 and 2.5-fold) and its marker compound glycycoumarin (2.3 and 1.6-fold). The metabolism of dolutegravir was also increased by G. glabra (2.8-fold) but not by its marker compound, glabridin. These results suggest that licorice and its phytochemicals could affect the metabolism and clearance of certain drugs that are substrates of CYP3A4 and CYP1A2.Supplemental data for this article is available online at https://doi.org/10.1080/19390211.2022.2050875 .

Wen Dan Tang: A Potential Jing Fang Decoction for Headache Disorders?

Background: Chinese herbal medicine is considered relatively safe, inexpensive, and easily accessible. Wen Dan Tang (WDT), a Jing Fang ancient classical Chinese herbal formula with a broad indication profile has been used for several centuries in China to treat various illnesses. Question: Are there evidence-based clinical trials that show that WDT has a significant impact on the treatment of various diseases, especially in patients with migraine and tension-type headaches (TTH)? Methods: This study is based on an online database search using PubMed, Medline, Cochrane Library, AcuTrials, Embase, Semantic Scholar, Jstor, internet research, and review of ancient and modern Chinese medical textbooks regarding WDT and its compounds. Results: There were no studies on WDT in migraine and TTH; therefore, this work gathers and describes data for every single compound in the formula. Conclusion: This study suggests that the bioactive compounds found in WDT composition show potential in treating patients with neurological, psychiatric disorders, cardiovascular diseases, metabolic syndrome, and digestive disorders. Some coherence between WDT in headache reduction and improvements in the quality of life in patients with migraines and TTH could be evaluated, showing positive results of WDT in these patients.

Gather wisdom to overcome barriers: Well-designed nano-drug delivery systems for treating gliomas

Due to the special physiological and pathological characteristics of gliomas, most therapeutic drugs are prevented from entering the brain. To improve the poor prognosis of existing therapies, researchers have been continuously developing non-invasive methods to overcome barriers to gliomas therapy. Although these strategies can be used clinically to overcome the blood‒brain barrier (BBB), the accurate delivery of drugs to the glioma lesions cannot be ensured. Nano-drug delivery systems (NDDS) have been widely used for precise drug delivery. In recent years, researchers have gathered their wisdom to overcome barriers, so many well-designed NDDS have performed prominently in preclinical studies. These meticulous designs mainly include cascade passing through BBB and targeting to glioma lesions, drug release in response to the glioma microenvironment, biomimetic delivery systems based on endogenous cells/extracellular vesicles/protein, and carriers created according to the active ingredients of traditional Chinese medicines. We reviewed these well-designed NDDS in detail. Furthermore, we discussed the current ongoing and completed clinical trials of NDDS for gliomas therapy, and analyzed the challenges and trends faced by clinical translation of these well-designed NDDS.

Dietary licorice enhances in vivo cadmium detoxification and modulates gut microbial metabolism in mice

Mass cadmium (Cd) poisoning is a serious health problem in many parts of the world. We propose that dietary intervention can be a practical solution to this problem. This study aimed to identify effective dietary products from traditional Chinese herbs that can detoxify Cd. Five candidate herbal foods with detoxifying potential were selected and subjected to mouse toxicological tests. The chemical composition and dose-response effects of licorice on mouse hepatocytes were determined. Licorice was selected for further tests to examine its effects on growth, tissue Cd accumulation, and gut and liver fitness of mice. The expression of hepatic metallothionein (Mt) genes was quantified in vitro in hepatocytes and in vivo in liver tissues of mice. The results showed that licorice dietary intervention was effective in reducing blood Cd by >50% within 1 month. Cd was also substantially reduced in the heart and lung tissues, but increased 2.1-fold in the liver. The liver of Cd poisoned mice improved with licorice intervention. Licorice treatment significantly induced Cd accumulation and expression of the Mt1 gene in hepatic cells both in vitro and in vivo. Licorice intake substantially altered gut microbial structure and enriched Parabacteroides distasonis. Omics results showed that licorice improved gut metabolism, particularly the metabolic pathways for glycyrrhizin, bile acids, and amino acids. Dietary licorice effectively reduced mouse blood Cd and had a profound impact on liver and gut fitness. We conclude that herbal licorice can be used as a dietary intervention for mass Cd poisoning.

Revisiting liquorice (Glycyrrhiza glabra L.) as anti-inflammatory, antivirals and immunomodulators: Potential pharmacological applications with mechanistic insight

BACKGROUND

Glycyrrhiza glabra L. (G. glabra) commonly known as liquorice is one of the highly exploited and utilized medicinal plant of the world. Since ancient times liquorice is considered as an auspicious and valuable traditional medicine across the world for treatment of various ailments.

METHOD

Several electronic online scientific databases such as Science Direct, PubMed, Scopus, Scifinder, Google Scholar, online books and reports were assessed for collecting information. All the collected information was classified into different sections to meet the objective of the paper.

RESULTS

The electronic database search yielded 3908 articles from different countries. Out of them one ninety-eight articles published between 1956 and 2021 were included, corresponding to all detailed review on G. glabra and research on anti-inflammatories, antivirals and immunomodulatory through pre-clinical and clinical models. From all selective area of studies on G. glabra and its bioactive components it was established (including molecular mechanisms) as a suitable remedy as per the current requirement of pandemic situation arise through respiratory tract infection.

CONCLUSION

Different relevant studies have been thoroughly reviewed to gain an insight on utility of liquorice and its bioactive constituents for anti-inflammatories, antivirals and immunomodulatory effects with special emphasized for prevention and treatment of COVID-19 infection with possible mechanism of action at molecular level. Proposed directions for future research are also outlined to encourage researchers to find out various mechanistic targets and useful value added products of liquorice in future investigations.

Is 18α-Glycyrrhizin a real natural product? Improved preparation of 18α-Glycyrrhizin from 18β-Glycyrrhizin as a positive standard for HPLC analysis of licorice extracts

18α-Glycyrrhizin is an epimer of 18β-glycyrrhizin, a major component of licorice (Glycyrrhiza sp.), which is widely used as a traditional medicine. Whether 18α-glycyrrhizin is a real natural product has been debated in the long history of glycyrrhizin chemistry because 18β-glycyrrhizin is epimerizable to a more thermodynamically stable 18α-glycyrrhizin under aqueous alkali conditions. We improved the preparation of 18α-glycyrrhizin from 18β-glycyrrhizin by successive epimerization reactions of 18β-glycyrrhizin, trimethyl esterification of the resulting epimerized mixture, and alkaline hydrolysis of a purified 18α-glycyrrhizin trimethyl ester. Approaches to the possible presence of 18α-glycyrrhizin in licorice extracts by HPLC using synthetic 18α-glycyrrhizin as a positive standard strongly suggested that 18α-glycyrrhizin could naturally exist as a minor congener of glycyrrhizin derivatives in Glycyrrhiza species.

Pharmacological Effects and Underlying Mechanisms of Licorice-Derived Flavonoids

Glycyrrhizae Radix et Rhizoma is the most frequently prescribed natural medicine in China and has been used for more than 2,000 years. The flavonoids of licorice have garnered considerable attention in recent decades due to their structural diversity and myriad pharmacological effects, especially as novel therapeutic agents against inflammation and cancer. Although many articles have been published to summarize different pharmacological activities of licorice in recent years, the systematic summary for flavonoid components is not comprehensive. Therefore, in this review, we summarized the pharmacological and mechanistic data from recent researches on licorice flavonoids and their bioactive components.

Antiproliferative and apoptotic potential of Glycyrrhizin against HPV16+ Caski cervical cancer cells: A plausible association with downreguation of HPV E6 and E7 oncogenes and Notch signaling pathway

Cervical cancer (CCa) is the second most frequent carcinoma in females and human papilloma virus (HPV) oncoproteins are regarded as one of the critical etiological agent. Despite recent advances in screening and management of CCa, still it remains the deadliest carcinoma as advanced and metastatic stages are mostly incurable. This urges for the development of newer therapeutic interventions. The current was aimed to investigate the antiproliferative and apoptotic potential of glycyrrhizin (Gly) against HPV16⁺ CaSki CCa cells. Our findings substantiated that Gly exerted antiproliferative effects on the CaSki cells by obstructing their proliferation rate. Gly substantially enhanced apoptosis in Caski cells in a dose-dependent manner via augmenting the generation of ROS, DNA fragmentation and disruption of the mitochondrial membrane potential. Gly mediated apoptosis in CaSki cells was found to be due to activation of caspase-8 and capsase-9 along with the modulation of pro-and anti-apoptotic gene expression. Moreover, Gly halts the progression of CaSki cells at G₀/G₁ phase which was found to be due to reduced expression of cyclin D1 and cyclin-dependent kinase 4 (CDK4) along with the enhanced expression of CDK inhibitor p21^Cip1. Further, Gly downregulates the expression of HPV oncoproteins (E6 & E7) along with the inhibition of Notch signaling pathway. Taken together, Gly represents as a potential therapeutic modality for CCa which could rapidly be translated for clinical studies.

Medicinal Uses of Licorice (Glycyrrhiza glabra L.): A Comprehensive Review

Innumerable plants have been used widely as integral medicinal sources since the start of human civilization. The demand for herbal medicines is constantly increasing with time overtime. Licorice ( Glycyrrhiza glabra family Leguminosae) is one of the most used herbal plants in foods, in medicinal forms, and substantially researched on a worldwide scale. It was used as traditional and complementary medicine against innumerable ailments including allergies, liver toxicity, gastric ulcer, lung diseases, skin disorders, oral health problems including tooth decay, and inflammation. The constituents of licorice include various essential oils, sugars, inorganic salts, resins, amino acids, and nucleic acids. Biological activity has been observed to be portrayed by active compounds of licorice including triterpene, flavonoids, and saponins. In recent years, licorice has been widely researched to discover its benefits, constituents, and its mechanism of action. The review summarizes the therapeutic and pharmacological benefits of licorice and its uses in different health-related conditions along with its toxicity and maximum levels of licorice consumption.

Licorice (Glycyrrhiza glabra) Extracts-Suitable Pharmacological Interventions for COVID-19? A Review

Even though vaccination has started against COVID-19, people should continue maintaining personal and social caution as it takes months or years to get everyone vaccinated, and we are not sure how long the vaccine remains efficacious. In order to contribute to the mitigation of COVID-19 symptoms, the pharmaceutical industry aims to develop antiviral drugs to inhibit the SARS-CoV-2 replication and produce anti-inflammatory medications that will inhibit the acute respiratory distress syndrome (ARDS), which is the primary cause of mortality among the COVID-19 patients. In reference to these tasks, this article considers the properties of a medicinal plant named licorice (Glycyrrhiza glabra), whose phytochemicals have shown both antiviral and anti-inflammatory tendencies through previous studies. All the literature was selected through extensive search in various databases such as google scholar, Scopus, the Web of Science, and PubMed. In addition to the antiviral and anti-inflammatory properties, one of the licorice components has an autophagy-enhancing mechanism that studies have suggested to be necessary for COVID-19 treatment. Based on reviewing relevant professional and historical literature regarding the medicinal properties of licorice, it is suggested that it may be worthwhile to conduct in vitro and in vivo studies, including clinical trials with glycyrrhizic and glycyrrhetinic acids together with other flavonoids found in licorice, as there is the potentiality to provide natural interventions against COVID-19 symptoms.

Culturable Endophytic Fungi from Glycyrrhiza inflata Distributed in Xinjiang, China with Antifungal Activity

A total of 99 endophytic fungal isolates were obtained from the roots of Glycyrrhiza inflata, which was a traditional medicinal plant mainly distributed in Xinjiang, China. Twenty-two distinct isolates were selected for further taxonomical identification by morphological traits and internal transcribed spacer (ITS) rRNA gene sequence analysis. Eleven genera were identified, among which Aspergillus, Alternaria and Fusarium were dominant. The crude extracts of 22 distinct identified fungi were successively evaluated for their antifungal activities on three rice fungal pathogens using the method of hyphal radial growth rate. Among them, the crude extract of Alternaria an-gustiovoidea Glinf007 showed the significantly mycelial growth inhibitory activity. The results demonstrated that G. inflata contained a diversity of culturable endophytic fungi, which could produce natural antimicrobial compounds that might be of great value to the agriculture and pharmaceutical industries.