18ß-glycyrrhetinic acid suppresses Lewis lung cancer growth through protecting immune cells from ferroptosis.

PURPOSE: 18ß-glycyrrhetinic acid (GA), the main metabolite of glycyrrhizic acid extracted from the root of licorice, has been reported to possess anti-cancer and immunomodulatory activity, but the mechanisms are not well understood. Recent studies have shown that ferroptosis of immune cells is involved in tumor-associated immune suppression. The purpose of this study was to investigate whether the enhanced immune response via inhibiting immune cell ferroptosis contributed to the anticancer effect of 18ß-GA. METHODS: Lewis Lung carcinoma mouse model and Murine CD8 + T cell culture model were used to examine the changes of immune response and ferroptosis of immune cells. RESULTS: We found that 18ß-GA was effective against lung cancer accompanied by enhanced activation of tumor-infiltrating CD8+ T cells in Lewis Lung carcinoma mouse model. Furthermore, we demonstrated that the boosted immune response by GA was attributed to its ability to inhibit arachidonic acid (AA)-mediated CD8+ T ferroptosis via suppressing CD36 expression. CONCLUSION: The findings of the present study unraveled a novel mechanism underlying the anti-cancer and immunomodulatory activity of 18ß-GA and support that 18ß-GA holds potential to be used as an immune enhancer for lung cancer prevention or treatment.

Ursodeoxycholic acid and 18ß-glycyrrhetinic acid alleviate ethinylestradiol-induced cholestasis via downregulating RORγt and CXCR3 signaling pathway in iNKT cells.

Estrogen-induced intrahepatic cholestasis (IHC) is a mild but potentially serious risk and urges for new therapeutic targets and effective treatment. Our previous study demonstrated that RORγt and CXCR3 signaling pathway of invariant natural killer T (iNKT) 17 cells play pathogenic roles in 17α-ethinylestradiol (EE)-induced IHC. Ursodeoxycholic acid (UDCA) and 18ß-glycyrrhetinic acid (GA) present a protective effect on IHC partially due to their immunomodulatory properties. Hence in present study, we aim to investigate the effectiveness of UDCA and 18ß-GA in vitro and verify the accessibility of the above targets. Biochemical index measurement indicated that UDCA and 18ß-GA presented efficacy to alleviate EE-induced cholestatic cytotoxicity. Both UDCA and 18ß-GA exhibited suppression on the CXCL9/10-CXCR3 axis, and significantly restrained the expression of RORγt in vitro. In conclusion, our observations provide new therapeutic targets of UDCA and 18ß-GA, and 18ß-GA as an alternative treatment for EE-induced cholestasis.

Glycyrrhetinic acid attenuates endoplasmic reticulum stress-induced hepatocyte apoptosis via CHOP/DR5/Caspase 8 pathway in cholestasis.

Bile acid (BA)-induced apoptosis is a common pathologic feature of cholestatic liver injury. Glycyrrhetinic acid (GA) is the hepatoprotective constituent of licorice. In the present study, the anti-apoptotic potential of GA was investigated in wild type and macrophage-depleted C57BL/6 mice challenged with alpha-naphthyl isothiocyanate (ANIT), and hepatocytes stimulated with Taurocholic acid (TCA) or Tumor necrosis factor-alpha (TNF-α). Apoptosis was determined by TUNEL positive cells and expression of executioner caspases. Firstly, we found that GA markedly alleviated liver injury, accompanied with reduced positive TUNEL-staining cells, and expression of caspases 3, 8 and 9 in mice modeled with ANIT. Secondly, GA mitigated apoptosis in macrophage-depleted mice with exacerbated liver injury and augmented cell apoptosis. In vitro study, pre-treatment with GA reduced the expression of activated caspases 3 and 8 in hepatocytes stimulated with TCA, but not TNF-α. The ability of GA to ameliorate apoptosis was abolished in the presence of Tauroursodeoxycholic Acid (TUDCA), a chemical chaperon against Endoplasmic reticulum stress (ER stress). Furthermore, GA attenuated the over-expression of Glucose regulated protein 78 (GRP78), and blocked all three branches of Unfolded protein reaction (UPR) in cholestatic livers of mice induced by ANIT. GA also downregulated C/EBP homologous protein (CHOP) expression, accompanied with reduced expression of Death receptor 5 (DR5) and activation of caspase 8 in both ANIT-modeled mice and TCA-stimulated hepatocytes. The results indicate that GA inhibits ER stress-induced hepatocyte apoptosis in cholestasis, which correlates with blocking CHOP/DR5/Caspase 8 pathway.

Exploring the molecular mechanism of glycyrrhetinic acid in the treatment of gastric cancer based on network pharmacology and experimental validation.

There is a wide range of pharmacological effects for glycyrrhetinic acid (GRA). Previous studies have shown that GRA could inhibit the proliferation of tumor cells, showing a promising value in the treatment of gastric cancer (GC). Nonetheless, the precise mechanism of the effect of GRA on GC remains unclear. We explored cellular and molecular mechanisms of GRA based on network pharmacology and in vitro experimental validation. In this study, we predicted 156 potential therapeutic targets for GC with GRA from public databases. We then screened the hub targets using protein-protein interaction network (PPI) and conducted clinical correlation analysis. Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment showed that GRA made anti-GC effects through multiple targets and pathways, particularly the MAPK signaling pathway. Next, molecular docking results revealed a potential interaction between GRA and MAPK3. In addition, qRT-PCR experiments revealed that 18ß-GRA was able to suppress mRNA expression of KRAS, ERK1 and ERK2 in AGS cells. Western blotting results also revealed that 18ß-GRA was able to suppress the expression of KRAS and p-ERK1/2 proteins in AGS cells. Additionally, immunofluorescence assays revealed that 18ß-GRA inhibited p-ERK1/2 nuclear translocation in AGS cells. These results systematically reveal that 18ß-GRA may have anti-tumor effects on GC by modulating the MAPK signaling pathway.

18ß-glycyrrhetinic Acid Modulated Autophagy is Cytotoxic to Breast Cancer Cells.

The development of endocrine therapy resistance in the luminal A subtype of breast cancer is related to the appearance of protective autophagy. The bioactive component from the root of licorice, 18ß-glycyrrhetinic acid (18ß-GA), has many antitumor properties. Whether 18ß-GA can modulate autophagy to inhibit proliferation of the luminal A subtype is still unclear. The proportion of apoptosis caused by 18ß-GA in MCF-7 and T-47D cells was determined using flow cytometry. The autophagy marker, LC3-II conversion, was investigated using Western blotting, and a PremoTM Tandem Autophagy Sensor Kit. We found that the concentration (150-µM) of 18ß-GA caused caspase-dependent apoptosis and LC3-II accumulation or blocked autophagic flux. Moreover, 18ß-GA-mediated apoptosis was improved using rapamycin but reversed by 3-methyladenine (3-MA) addition. The phosphorylation level of Jun-amino-terminal kinase (JNK) was increased significantly in the 18ß-GA treatment and combined incubation using rapamycin. A JNK inhibitor (SP600125) significantly inhibited 18ß-GA-mediated apoptosis, LC3-II accumulation and rescued the numbers of MCF-7 and T-47D colony formation. Especially, 18ß-GA can inhibit xenograft tumor growth in BALB/c nude mice. These data indicate the combination of 18ß-GA with rapamycin or 3-MA can sensitize or decrease MCF-7 and T-47D cells to 18ß-GA-induced apoptosis, respectively. 18ß-GA modulated autophagy is cytotoxic to luminal A subtype breast cancer cells through apoptosis promotion and JNK activation.

Construction of redox-sensitive liposomes modified by glycyrrhetinic acid and evaluation of anti-hepatocellular carcinoma activity.

The aim of this study was to construct a bifunctional liposome with hepatic-targeting capacity by modifying with a targeting ligand and an intracellular tumor reduction response functional group to deliver drugs precisely to focal liver tissues and release them in large quantities in hepatocellular carcinoma cells. This could improve drug efficacy and reduce toxic side effects at the same time. First, the bifunctional ligand for liposome was successfully obtained by chemically synthesizing it from the hepatic-targeting glycyrrhetinic acid (GA) molecule, cystamine, and the membrane component cholesterol. Then the ligand was used to modify the liposomes. The particle size, PDI and zeta potential of the liposomes were determined with a nanoparticle sizer, and the morphology was observed by transmission electron microscopy. The encapsulation efficiency and drug release behavior were also determined. Further, the stability in vitro of the liposomes and the changes in the simulated reducing environment were determined. Finally, the antitumor activity in vitro and cellular uptake efficiency of the drug-loaded liposomes were investigated by performing cellular assays. The results showed that the prepared liposomes had a uniform particle size of 143.6 ± 2.86 nm with good stability and an encapsulation rate of 84.3 ± 2.1 %. Moreover, the particle size of the liposomes significantly increased and the structure was destroyed in a DTT reducing environment. Cellular experiments showed that the modified liposoes had better cytotoxic effects on hepatocarcinoma cells than both normal liposomes and free drugs. This study has great potential for tumor therapy and provides novel ideas for the clinical use of oncology drugs in dosage forms.

Synthesis of glycyrrhetinic acid-modified liposomes to deliver Murrayafoline A for treatment of hepatocellular carcinoma.

Hepatocellular carcinoma is a common type of cancer associated with a high mortality rate. Among several bioactive compounds, Murrayafoline A (MuA) has been proved as a bio substance that exhibits great potentials in treating liver cancer. In order to overcome the high cytotoxicity and low solubility of MuA, a delivery system based on nanocarriers is necessary to deliver MuA towards the desired target. In the present study, 18ß-glycyrrhetinic acid (GA), which is known as a ligand for liver targeting, was used to construct the cholesterol-poly (ethylene glycol)-glycyrrhetinic acid (GA-PEG-Chol) conjugate and liposome for MuA administration. The compound was then examined for therapeutic efficacy and safety in HUVEC and HepG2 cells in 2D and 3D cell cultures. Results have shown that MuA-loaded liposomes had IC50 value of 2 µM in HepG2 and had the cytosolic absorption of 8.83 ± 0.97 ng/105 cells, while The IC50 value of MuA-loaded liposomes in HUVEC cell lines was 15 µM and the the cytosolic absorption was recorded as 3.62 ± 0.61 cells. The drug test on the 3D cancer sphere platform of the HepG2 cancer sphere showed that MuA-loaded GA liposomes had the highest efficacy at a concentration of 100 µg/mL. In short, these results suggest that MuA-loaded GA liposomes have the potential for maintenance drug delivery and liver targeting.

[Preparation of salvianolic acid B, tanshinone â ¡_A, and glycyrrhetinic acid lipid emulsion and its protective effect against acute liver injury induced by acetaminophen].

Salvianolic acid B(Sal B), tanshinone Ⅱ_A(TSN Ⅱ_A), and glycyrrhetinic acid(GA) lipid emulsion(GTS-LE) was prepared by the high-speed dispersion method combined with ultrasonic emulsification.The preparation process of the emulsion was optimized by single-factor method and D-optimal method with appearance, centrifugal stability, and particle size of the emulsion as evalua-tion indexes, followed by verification.In vitro release of Sal B, TSN Ⅱ_A, and GA in GTS-LE was performed by reverse dialysis.In vivo pharmacokinetic evaluation was carried out in mice.The acute liver injury model was induced by acetaminophen.The effect of oral GTS-LE on the acute liver injury was investigated by serum liver function indexes and pathological changes in liver tissues of mice.The results showed that under the optimal preparation process, the average particle size of GTS-LE was(145.4±9.25) nm and the Zeta potential was(-33.6±1.45) mV.The drug-loading efficiencies of Sal B, TSN Ⅱ_A, and GA in GTS-LE were above 95%, and the drug release in vitro conformed to the Higuchi equation.The pharmacokinetic results showed that the C_(max) of Sal B, TSN Ⅱ_A, and GA in GTS-LE was 3.128, 2.7, and 2.85 times that of the GTS-S group, and AUC_(0-t) of Sal B, TSN Ⅱ_A, and GA in GTS-LE was 3.09, 2.23, and 1.9 times that of the GTS-S group.After intragastric administration of GTS-LE, the activities of alanine aminotransferase and aspartate aminotransferase were significantly inhibited, the content of malondialdehyde was reduced, and the structure of hepatocytes recovered to normal.In conclusion, GTS-LE can delay the release of Sal B and promote the release of TSN Ⅱ_A and GA.The encapsulation of three drug components in the emulsion can improve the oral bioavailability to varying degrees and can effectively prevent the acute liver injury caused by acetaminophen.

Collagenase-I decorated co-delivery micelles potentiate extracellular matrix degradation and hepatic stellate cell targeting for liver fibrosis therapy.

Liver fibrosis is a pathological process of multiple chronic liver diseases progressing to cirrhosis for which there are currently no effective treatment options. During fibrosis progression, the overproduction of extracellular matrix (ECM) collagen secreted by hepatic stellate cells (HSCs) greatly impedes drug delivery and reduces drug therapeutic effects. In this study, a glycyrrhetinic acid (GA)-conjugated prodrug micellar system with collagenase I (COL) decoration (COL-HA-GA, abbreviated as CHG) was designed to codelivery sorafenib (Sora/CHG, abbreviated as S/CHG) for potentiating ECM degradation and HSCs targeting on liver fibrosis therapy. In ECM barrier models established in vitro or in vivo, CHG micelles efficiently degraded pericellular collagen and demonstrated enormous ECM penetration abilities as well as superior HSCs internalization. Moreover, CHG micelles exhibited more Sora & GA accumulations and activated HSCs targeting efficiencies in the fibrotic livers than those in the normal livers. More importantly, S/CHG micelles were more effective in anti-liver fibrosis by lowering the collagen content, inhibiting the HSCs activation, as well as down-regulating the fibrosis-related factors, leading to reverse the fibrotic liver to normal liver through the multi-mechanisms including angiogenesis reduction, liver fibrosis microenvironment regulation, and epithelial-mesenchymal transition inhibition. In conclusion, the developed COL decorated nano-codelivery system with fibrotic ECM collagen degradation and activated HSCs targeting dual-functions exhibited great potential for liver fibrosis therapy. STATEMENT OF SIGNIFICANCE: A glycyrrhetinic acid (GA)-conjugated prodrug with collagenase I (COL) decoration (CHG) was designed for codelivery with sorafenib (S/CHG), potentiating extracellular matrix (ECM) degradation-penetration and hepatic stellate cells (HSCs) targeting on liver fibrosis therapy. In ECM barrier models, CHG micelles efficiently degraded pericellular collagen and demonstrated ECM penetration abilities, as well as displayed superior HSCs internalization. Moreover, S/CHG micelles were more effective in anti-liver fibrosis by lowering the collagen content, inhibiting the HSCs activation, as well as down-regulating cytokines, reversing the fibrotic liver to normal through various mechanisms. In conclusion, the developed fibrotic ECM degradation and HSCs targeting dual-functional nano-codelivery system provided a prospective potentiality in liver fibrosis therapy.

Glycyrrhetinic acid regulates impaired macrophage autophagic flux in the treatment of non-alcoholic fatty liver disease.

Macrophages are involved in hepatocyte steatosis and necroinflammation and play an important role in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). Impaired autophagy function (decreased autophagy or blocked autophagic flow) leads to cell damage and death and promotes NAFLD progression. The experimental and clinical research of glycyrrhetinic acid (GA) in the treatment of NAFLD has gradually attracted attention with clear pharmacological activities such as immune regulation, antiviral, antitumor, antioxidant, liver protection, and anti-inflammatory. However, the effects of GA on the STAT3-HIF-1α pathway and autophagy in macrophages are still unclear, and its mechanism of action in the treatment of NAFLD remains to be further elucidated. We constructed a NAFLD mouse model through a high-fat and high-sugar diet to investigate the therapeutic effects of GA. The results showed that GA reduced weight, improved the pathological changes and hepatic lipid deposition of liver, and abnormally elevated the levels of serum biochemical (AST, ALT, TG, T-CHO, LDL-C, and HDL-C) and inflammatory indexes (IL-1ß, IL-4, IL-6, MCP-1, and TNF-α) in NAFLD mice. Further examination revealed that GA ameliorates excessive hepatic macrophage infiltration and hepatocyte apoptosis. The results of the cell experiments further elaborated that GA modulated the PA-induced macrophage STAT3-HIF-1α pathway and ameliorated impaired autophagic flux (blockade of autophagosome-lysosome fusion) and overactivation of inflammation. Excessive hepatocyte apoptosis caused by the uncontrolled release of inflammatory cytokines was also suppressed by GA. Conclusion: This study demonstrated that GA could regulate the STAT3-HIF-1α pathway of macrophages, ameliorate the impaired autophagy flux, and reduce the excessive production of inflammatory cytokines to improve the excessive apoptosis of liver cells, thus playing a therapeutic role on NAFLD.

Transcriptional profile changes after treatment of ischemia reperfusion injury-induced kidney fibrosis with 18ß-glycyrrhetinic acid.

INTRODUCTION: Chronic kidney disease (CKD) is characterized by renal fibrosis without effective therapy. 18ß-Glycyrrhetinic acid (GA) is reported to have detoxification and anti-inflammatory functions and promotes tissue repair. However, the role of GA in CKD remains unclear. In this study, we investigated whether GA has a potential therapeutic effect in kidney fibrosis. METHODS: A renal fibrosis mouse model was established by ischemia/reperfusion (I/R) injury via clamping unilateral left renal pedicle for 45 min; then, the mice were treated with vehicle or GA. Kidney tissues and blood samples were extracted 14 days after reperfusion and renal function, histopathological staining, quantitative PCR, and western blotting were performed. RNA-seq was performed to explore the changes in the transcriptional profile after GA treatment. RESULTS: Renal function, pathological and molecular analysis displayed that fibrosis was successfully induced in the I/R model. In the GA treatment group, the severity of fibrosis gradually reduced with the best effect seen at a concentration of 25 mg kg -1. A total of 970 differentially expressed genes were identified. Pathway enrichment showed that reduced activation and migration of inflammatory cells and decreased chemokine interaction in significant pathways. Protein-protein interaction networks were constructed and 15 hub genes were selected by degree rank, including chemokines, such as C3, Ccl6, Ccr2, Ptafr, Timp1, and Pf4. CONCLUSIONS: GA may alleviate renal fibrosis by inhibiting the inflammatory response. GA is a promising therapy that may perhaps be used in treating renal fibrosis and CKD.

Glycyrrhetinic acid: A potential drug for the treatment of COVID-19 cytokine storm.

BACKGROUND: The cytokine storm (CS) triggered by coronavirus disease 2019 (COVID-19) has caused serious harm to health of humanity and huge economic burden to the world, and there is a lack of effective methods to treat this complication. PURPOSE: In this research, we used network pharmacology and molecular docking to reveal the interaction mechanism in the glycyrrhetinic acid (GA) for the treatment of CS, and validated the effect of GA intervention CS by experiments. STUDY DESIGN: First, we screened corresponding target of GA and CS from online databases, and obtained the action target genes through the Venn diagram. Then, protein-protein interaction (PPI) network, Gene ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment of the action target genes were acquired by R language to predict its mechanism. Next, molecular docking was performed on core targets. Finally, experiments in which GA intervened in lipopolysaccharide (LPS)-induced CS were implemented. RESULTS: 84 action target genes were obtained from online database. The PPI network of target genes showed that TNF, IL6, MAPK3, PTGS2, ESR1 and PPARG were considered as the core genes. The results of GO and KEGG showed that action target genes were closely related to inflammatory and immune related signaling pathways, such as TNF signaling pathway, IL-17 signaling pathway, Human cytomegalovirus infection, PPAR signaling pathway and so on. Molecule docking results prompted that GA had fine affinity with IL6 and TNF proteins. Finally, in vivo and in vitro experimental results showed that GA could significantly inhibit LPS-induced CS. CONCLUSION: GA has a potential inhibitory effect on CS, which is worthy of further exploration.

Evaluation of a new-formula shampoo containing 6% glycyrrhetinic acid complex for scalp seborrheic dermatitis: A pilot study.

BACKGROUND: Scalp seborrheic dermatitis (SD) is a chronic inflammatory dermatosis associated with sebum imbalance and proliferation of Malassezia species. Various antifungal shampoos are commonly used for scalp SD. AIMS: Glycyrrhetinic acid is known to have antioxidative, anti-inflammatory, and anti-allergic effects. This study was designed to evaluate the effectiveness of a new-formula shampoo that contains glycyrrhetinic acid for the treatment of scalp SD. PATIENTS/METHODS: Thirty-four patients were enrolled and treated with the 6% glycyrrhetinic acid complex shampoo. Efficacy was assessed clinically with Dermatology Life Quality Index (DLQI) and Adherent Scalp Flaking Score (ASFS) by the same dermatologist at baseline, week 2, and week 5. Among the 24 subjects with the most significant clinical improvement, four common microorganisms from scalp samples were analyzed by quantitative polymerase chain reaction (qPCR) at baseline, and week 5. RESULTS: The DLQI and ASFS at week 2 and week 5 improved significantly relative to baseline. The bacteria profiles showed a significant increase of Cutibacterium acnes and a decrease of Staphylococcus epidermidis at week 5. The fungi profiles showed significant decreases of both Malassezia restricta and Malassezia globosa. The ratio of C. acne to S. epidermidis increased significantly from 0.93 at baseline to 1.55 at week 5. The ratio of M. restricta to M. globosa decreased from 5.02 at baseline to 1.00 at week 5. CONCLUSIONS: The effectiveness of this new regimen was objectively demonstrated at the clinical and microbiological levels. This new formula may alleviate the bacterial and fungal dysbiosis in scalp SD.

In vitro anthelmintic activity of an aqueous extract of Glycyrrhiza glabra and of glycyrrhetinic acid against gastrointestinal nematodes of small ruminants.

This study evaluated the in vitro anthelmintic activity of a liquorice (Glycyrrhiza glabra) root aqueous extract and of glycyrrhetinic acid at 30, 10, 5, 1, and 0.5 mg/mL against sheep gastrointestinal nematodes (GINs), using the egg hatch test (EHT), the larval development test (LDT), and the larval migration inhibition test (LMIT). The compounds were applied on a mixture of GIN eggs and larvae, mainly Trichostrongylus spp. and Teladorsagia/Ostertagia spp. Cytotoxicity assays were also performed. In the EHT, both candidates showed significant concentration-dependent efficacy and were significantly more effective (p < 0.001) at the highest concentrations (30 and 10 mg/mL) than the lowest ones. In the LDT, only G. glabra showed a concentration-dependent effect (R2 = 0.924), but glycyrrhetinic acid (R2 = 0.910) had significantly higher efficacy than G. glabra root extract. Moreover, the efficacy of glycyrrhetinic acid at 30, 10, and 5 mg/mL was significantly higher (p < 0.001) than at lower concentrations. In the LMIT, G. glabra showed concentration-dependent efficacy (R2 = 0.971), while considerably reduced efficacy was observed for glycyrrhetinic acid (R2 = 0.855) at the lowest concentrations. These data suggest that the two compounds may have different mechanisms of action. In the LMIT, the 50% lethal concentration (LC50) of glycyrrhetinic acid (~5.12 mg/mL) was > 2.0-fold lower when compared to G. glabra (12.25 mg/mL). Analysis and previous findings indicated low toxicity for both compounds. The results obtained encourage in vivo studies aimed at evaluating the potential use of the tested compounds as natural de-wormers in ruminants.

TITLE: Activité anthelminthique in vitro d'un extrait aqueux de Glycyrrhiza glabra et de l'acide glycyrrhétinique contre les nématodes gastro-intestinaux des petits ruminants. ABSTRACT: Cette étude a évalué l'activité anthelminthique in vitro d'un extrait aqueux de racine de réglisse (Glycyrrhiza glabra) et de l'acide glycyrrhétinique à 30, 10, 5, 1 et 0,5 mg/mL contre les nématodes gastro-intestinaux (NGI) du mouton, en utilisant le test d'éclosion des œufs (TEO), le test de développement larvaire (TDL) et le test d'inhibition de la migration larvaire (TIML). Les composés ont été appliqués sur un mélange d'œufs et de larves de NGI, principalement Trichostrongylus spp. et Teladorsagia/Ostertagia spp. Des tests de cytotoxicité ont également été effectués. Dans le TEO, les deux candidats ont montré une efficacité concentration-dépendante significative et ont été significativement plus efficaces (p < 0,001) aux concentrations les plus élevées (30 et 10 mg/mL) qu'aux plus faibles. Dans le TDL, seul G. glabra a montré un effet concentration-dépendant (R2 = 0,924), mais l'acide glycyrrhétinique (R2 = 0,910) avait une efficacité significativement plus élevée que l'extrait de racine de G. glabra. De plus, l'efficacité de l'acide glycyrrhétinique à 30, 10 et 5 mg/mL était significativement plus élevée (P < 0,001) qu'à des concentrations plus faibles. Dans le TIML, G. glabra a montré une efficacité concentration-dépendante (R2 = 0,971), tandis qu'une forte réduction d'efficacité a été observée pour l'acide glycyrrhétinique (R2 = 0,855) aux concentrations les plus faibles. Ces données peuvent suggérer que les deux composés peuvent avoir des mécanismes d'action différents. Dans le TIML, la concentration létale à 50% (CL50) de l'acide glycyrrhétinique (~ 5,12 mg/mL) était > 2,0 fois inférieure à celle de G. glabra (12,25 mg/mL). L'analyse et les résultats précédents ont indiqué une faible toxicité pour les deux composés. Les résultats obtenus encouragent les études in vivo visant à évaluer l'utilisation potentielle des composés testés ici comme anthelminthique naturels chez les ruminants.

Can Antiviral Activity of Licorice Help Fight COVID-19 Infection?

The phytotherapeutic properties of Glycyrrhiza glabra (licorice) extract are mainly attributed to glycyrrhizin (GR) and glycyrrhetinic acid (GA). Among their possible pharmacological actions, the ability to act against viruses belonging to different families, including SARS coronavirus, is particularly important. With the COVID-19 emergency and the urgent need for compounds to counteract the pandemic, the antiviral properties of GR and GA, as pure substances or as components of licorice extract, attracted attention in the last year and supported the launch of two clinical trials. In silico docking studies reported that GR and GA may directly interact with the key players in viral internalization and replication such as angiotensin-converting enzyme 2 (ACE2), spike protein, the host transmembrane serine protease 2, and 3-chymotrypsin-like cysteine protease. In vitro data indicated that GR can interfere with virus entry by directly interacting with ACE2 and spike, with a nonspecific effect on cell and viral membranes. Additional anti-inflammatory and antioxidant effects of GR cannot be excluded. These multiple activities of GR and licorice extract are critically re-assessed in this review, and their possible role against the spread of the SARS-CoV-2 and the features of COVID-19 disease is discussed.

Efficacy and safety of a new vaginal gel for the treatment of symptoms associated with vulvovaginal atrophy in postmenopausal women: A double-blind randomized placebo-controlled study.

OBJECTIVE: The aim of the present randomized placebo-controlled single-center study was to assess the efficacy and safety of a new vaginal gel (Meclon Idra - Alfasigma) in the treatment of vulvovaginal atrophy (VVA). The gel is composed of sea buckthorn (Hippophaë rhamnoides) oil, aloe vera, 18ß-glycyrrhetic acid, hyaluronic acid and glycogen. The study assessed whether the gel can reduce VVA symptoms (vaginal dryness, itching, burning sensation) and improve sexual function in postmenopausal women over 12 weeks. STUDY DESIGN: Postmenopausal women (n° = 60) reporting VVA symptoms were recruited and randomized in a 1:1 ratio to the gel or placebo. Active vaginal gel or placebo was applied for 14 days and then twice a week for 90 consecutive days. MAIN OUTCOME MEASURE: The Vaginal Health Index (VHI), including vaginal pH, was used to assess changes in objective signs, whereas the self-reported Female Sexual Function Index (FSFI) was used to investigate sexual function. RESULTS: Meclon Idra was effective in reducing vaginal pain, dyspareunia and vaginal pH, with the VHI showing significant improvement at day 90 (P < .0001), and in reducing each VVA symptom (vaginal dryness, vaginal itching, burning sensation) at weeks 2 and 4, and the end of the study (P < .0001). The analysis of FSFI scores showed, after the end of treatment, an improvement of sexual function in the active-treatment group, with a statistically significant increase (P < 0.001) in all domains scores and total score (P < 0.001). CONCLUSIONS: The present single-center randomized clinical trial demonstrated the efficacy, tolerability and safety of 12-week treatment with a new vaginal gel in postmenopausal women with symptoms associated with VVA. Based on this trial, the gel seems to be a valid choice as a single, local agent for relieving VVA symptoms and improving sexual function, and to have good compliance. This trial is registered prospectively with the Clinical Trials Registry - India, number CTRI/2019/05/01911.

18ß-Glycyrrhetinic acid alleviates demyelination by modulating the microglial M1/M2 phenotype in a mouse model of cuprizone-induced demyelination.

This research aimed to examine the nutritious supplementary function of 18ß-Glycyrrhetinic acid (18ß-GA) in moderating the myelin sheath destruction and behavioral impairments observed in the cuprizone model of demyelination. Mice were fed daily on food containing cuprizone (0.3 %) and given doses of 18ß-GA (5 or 1 mg/kg) for a period of five weeks. The groups treated with 18ß-GA exhibited improvements in exploratory behavior, locomotive activity, and weight. As assessed using luxol-fast blue and myelin basic protein (MBP) staining, which were used to detect demyelination in the brain, 18ß-GA both reduced and prevented instances of cuprizone-induced demyelinating lesions; treatment with 18ß-GA also caused the MBP level in the corpus callosum to increase. Furthermore, alongside these positive results following 18ß-GA treatment, microglial polarisation was also observed to shift towards the beneficial M2 phenotype. The results of this research thus indicate the potential clinical application of 18ß-GA for the prevention of myelin damage and behavioral dysfunction.

Glycyrrhetinic acid remodels the tumor microenvironment and synergizes with doxorubicin for breast cancer treatment in a murine model.

We aimed to combine glycyrrhetinic acid with doxorubicin to prepare, characterize and evaluate a drug delivery nano-system with REDOX sensitivity for the treatment of breast cancer. M-DOX-GA NPs prepared by nano sedimentation were spherical, with a particle size of 181 nm. And the maximum encapsulation efficiency and drug loading in M-DOX-GA NPs were 89.28% and 18.22%, respectively. Cytotoxicity and cellular uptake experiments of nanoparticles to KC cells, Cal-27 cells and 4T1 cells were studied by the CCK-8 method. The result indicated that M-DOX-GA NPs could accurately release the drug into the tumor cells, thus achieving the targeted release of the drug. Comparing the survival rate of the above three cells, it was found that M-DOX-GA NPs had a good tumor selectivity and had a more significant therapeutic effect on breast cancer. A 4T1-bearing mouse model was established, and the tumor inhibition rate was 77.37% after injection of nanoparticle solution for 14 d. Normal tissue H&E stained sections and TUNEL assay were verified M-DOX-GA NPs have excellent tumor suppressive effect, and can efficiently reduce the toxic side effects on normal organisms, and effectively avoided 4T1 cells metastasis. Immunofluorescence detection and Western-blot analysis figured a decline in both CUGBP1 and α-SMA, which verifying the TME remodeling induced by glycyrrhetinic acid. Collectively, the combination of doxorubicin and glycyrrhetinic acid is an effective and safe strategy for remodeling fibrotic TME by improving the therapeutic outcome for breast cancer.

Research progress on the protective effects of licorice-derived 18ß-glycyrrhetinic acid against liver injury.

The first description of the medical use of licorice appeared in "Shennong Bencao Jing", one of the well-known Chinese herbal medicine classic books dated back to 220-280 AD. As one of the most commonly prescribed Chinese herbal medicine, licorice is known as "Guo Lao", meaning "a national treasure" in China. Modern pharmacological investigations have confirmed that licorice possesses a number of biological activities, such as antioxidation, anti-inflammatory, antiviral, immune regulation, and liver protection. 18ß-glycyrrhetinic acid is one of the most extensively studied active integrants of licorice. Here, we provide an overview of the protective effects of 18ß-glycyrrhetinic acid against various acute and chronic liver diseases observed in experimental models, and summarize its pharmacological effects and potential toxic/side effects at higher doses. We also make additional comments on the important areas that may warrant further research to support appropriate clinical applications of 18ß-glycyrrhetinic acid and avoid potential risks.

Structure-based design of glycyrrhetinic acid derivatives as potent anti-sepsis agents targeting high-mobility group box-1.

Novel Glycyrrhetinic Acid (GA) derivatives with fused heterocycles on A ring were structure-based designed and synthesized. Their potential anti-inflammatory effects were investigated by a classical LPS stimulated macrophage model. Surface plasmon resonance (SPR) was used to verify the binding of GA analogues with HMGB1. A preliminary structure-activity relationship was summarized and an analogue GA-60 with ortho-methoxybenzyl pyrozole showed stronger anti-inflammatory effect and higher affinity for HMGB1 with a Kd value of 12.5 µM. In addition, this compound exhibited excellent inhibitory functions on NO (96%), TNF-α (94%), and IL-6 (100%), by interfering with phosphorylation of p38, ERK, JNK MAPKs, as well as that of NF-κB p65 and IKKα/ß. Moreover, GA-60 extended the survival of either the classic CLP-induced or LPS-induced sepsis mouse models. Molecular modeling predictions further supported these findings, clearly indicating that inhibiting HMGB1 release, using fused heterocyclic GA derivatives, is a promising strategy for treatment of sepsis.