Chalcone derivatives from licorice inhibit human and rat gonadal 3β-hydroxysteroid dehydrogenases as therapeutic uses

ETHNOPHARMACOLOGICAL RELEVANCE

In traditional Chinese medicine, licorice (the roots of Glycyrrhiza glabra and G. inflata) has been used to treat inflammation and sexual debility for over 1000 years. Pharmacological studies have identified many biologically active chalcone derivatives from licorice.

AIM OF THE STUDY

Human 3β-Hydroxysteroid dehydrogenase 2 (h3β-HSD2) catalyzes the formation of precursors for sex hormones and corticosteroids, which play critical roles in reproduction and metabolism. We explored inhibition and mode action of chalcones of inhibiting h3β-HSD2 and compared it with rat 3β-HSD1.

MATERIALS AND METHODS

We investigated the inhibition of 5 chalcones on h3β-HSD2 and compared species-dependent difference with 3β-HSD1.

RESULTS

The inhibitory strength on h3β-HSD2 was isoliquiritigenin (IC50, 0.391 μM) > licochalcone A (0.494 μM) > licochalcone B (1.485 μM) > echinatin (1.746 μM) >chalcone (100.3 μM). The inhibitory strength on r3β-HSD1 was isoliquiritigenin (IC50, 0.829 μM) > licochalcone A (1.165 μM) > licochalcone B (1.866 μM) > echinatin (2.593 μM) > chalcone (101.2 μM). Docking showed that all chemicals bind steroid and/or NAD+-binding site with the mixed mode. Structure-activity relationship analysis showed that strength was correlated with chemical's hydrogen bond acceptor.

CONCLUSION

Some chalcones are potent h3β-HSD2 and r3β-HSD1 inhibitors, possibly being potential drugs to treat Cushing's syndrome or polycystic ovarian syndrome.

Research Progress on Structural Modification of Effective Antitumor Active Ingredients in Licorice

Licorice, a widely used traditional Chinese medicine, contains more than 300 flavonoids and more than 20 triterpenoids, which have potential medicinal value and can prevent the growth of tumor cells by blocking the cell cycle, affecting the regulation of the apoptosis gene of tumor cells, and inhibiting tumor cell angiogenesis. However, many of the compounds in licorice still have the drawbacks of poor solubility, significant toxic side effects, and low antitumor activity. This article reviews the structural modification of effective antitumor active ingredients in licorice, thus providing a theoretical basis for further investigation of licorice and the development of new antitumor drugs.

Isoliquiritigenin from licorice flavonoids attenuates NLRP3-mediated pyroptosis by SIRT6 in vascular endothelial cells

ETHNOPHARMACOLOGIC RELEVANCE

Licorice is a traditional Chinese medicine that has been used for cardiovascular diseases. Recent studies found that supplementation with licorice extracts attenuated the development of atherosclerosis (AS) in hypercholesterolemic patients. Many studies have shown that licorice flavonoids, the main active components of licorice, have a variety of pharmacological effects, including anti-inflammation, regulation of lipid metabolism, and antioxidation. However, the key active components against AS in licorice flavonoids are still unclear.

AIM OF THE STUDY

The aim of this paper is to investigate the active components of licorice flavonoids that exert anti-atherosclerotic effects and the underlying mechanisms.

MATERIALS AND METHODS

Network pharmacology was used to screen the active components of licorice flavonoids that have anti-atherosclerotic effects. Combining bioinformatics analysis and in vitro studies, the effects and underlying mechanisms of the active component isoliquiritigenin (ISL) on cell pyroptosis were further investigated in tumor necrosis factor (TNF)-α-treated human umbilical vein endothelial cells (HUVECs).

RESULTS

We constructed a compound-target network and screened 3 active components, namely, ISL, glabridin, and naringenin in licorice flavonoids. The half maximal effective concentration values of these 3 components suggested that ISL was the key active component against TNF-α-induced endothelial cell injury. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that ISL could potentially treat AS via the nucleotide-binding and oligomerization domain (NOD)-like receptor signaling pathway. An in vitro study verified that ISL suppressed TNF-α-induced NLRP3 activation and pyroptosis in HUVECs. The molecular docking and cellular thermal shift assay showed good compatibility between ISL and class III histone deacetylase sirtuin 6 (SIRT6). Moreover, we found that ISL upregulated the expression of SIRT6 in TNF-α-treated HUVECs. Further study found that SIRT6 knockdown reduced the inhibitory effect of ISL on pyroptosis, whereas the NLRP3 inhibitor reversed this process in TNF-α-treated HUVECs.

CONCLUSIONS

Our results demonstrate that ISL is a key active component of licorice flavonoids. ISL attenuates NLRP3-mediated vascular endothelial cell pyroptosis via SIRT6, and SIRT6 may be a potential target of ISL for the treatment of AS.