Exploration for the real causative agents of licorice-induced pseudoaldosteronism

Shaoyao Gancao decoction, an Ancient Classical Prescription: a review on its chemical composition, pharmacology, pharmacokinetics, clinical applications, and toxicology

OBJECTIVES

Shaoyao Gancao decoction (SGD) is a famous Ancient Classical Prescription (ACP) from "Treatise on Febrile Diseases." It has been clinically used for spasm- and pain-related disorders induced by insufficiency of Qi and blood and malnutrition of tendons and vessels for thousands of years. To expand comprehensive understanding and to highlight the importance of more effective utilization, this study aimed to provide a comprehensive review of SGD covering multiple research fields.

METHODS

Some databases, including PubMed, Web of Science, Google Scholar, and China National Knowledge Infrastructure, were used to collect the related information with "Shaoyao Gancao decoction" and similar ones as the keywords.

KEY FINDINGS

Phytochemical researches revealed that flavonoids and monoterpenoids were the predominant components in SGD. It was documented that SGD had demonstrated a variety of effects, such as analgesic and anti-inflammatory activity, neuroprotection, antispasmodic activity, gastrointestinal protection, hepatoprotection, anti-asthma activity, and effects on gynecological diseases. As for its toxicology, pseudoaldosteronism occasionally occurred and 18β-glycyrrhetyl-3-O-sulfate was believed to be a causative agent.

CONCLUSIONS

As a whole, many valuable achievements have been made, exhibiting great attraction and potential of SGD as a famous ACP. This review is also expected to facilitate SGD application and research in the future.

Licorice and liver function in patients with primary liver disease: A systematic review and meta-analysis of RCTs

Licorice (Glycyrrhiza spp.) has been a cornerstone of traditional Chinese and Japanese medicine. This systematic review and meta-analysis aimed to evaluate the efficacy of licorice formulations, alone or in combination with other herbs, on liver function enzymes in patients with primary liver disease. We systematically searched MEDLINE, Embase, Scopus, Web of Science, and Cochrane Library up to April 2024. Randomized controlled trials (RCTs) comparing the effects of Glycyrrhiza spp. preparations versus placebo or standard of care controls were included. Standard Cochrane methods were used to extract data and appraise eligible studies. A total of 15 RCTs, involving 1367 participants, were included in the analysis. The studies varied widely in geographical location, duration, and licorice preparations used. Licorice significantly reduced alanine aminotransferase (ALT) by 15.63 U/L (95% CI: -25.08, -6.18; p = 0.001) and aspartate aminotransferase (AST) by 7.37 U/L (95% CI: -13.13, -1.61; p = 0.01) compared to control groups. Subgroup analyses revealed that purified glycyrrhizic acid compounds were particularly effective, showing greater reductions in ALT and AST without significant heterogeneity. Although licorice treatment did not significantly impact gamma-glutamyl transferase and total bilirubin (TBIL) levels overall, specific licorice-herb preparations did show a notable reduction in TBIL. The safety profile of licorice was consistent with known side effects, predominantly mild and related to its mineralocorticoid effects. Despite heterogeneity and potential language bias, the findings suggest that licorice can enhance liver function. Further studies should standardize licorice preparations and explore its role in multifaceted herbal formulations to better understand its hepatoprotective mechanisms.

Torsade de Pointes Caused by a Compound Licorice Tablet

The clinical manifestations of licorice-induced pseudoaldosteronism include muscle weakness, periodic paralysis, hypokalemia, and hypertension. Excessive licorice consumption can lead to adverse reactions affecting multiple systems, including the endocrine, cardiovascular, nervous, digestive, and immune systems. Although licorice is a frequently used Chinese herbal medicine, life-threatening adverse reactions have been reported among its users. This article presents a case of severe hypokalemia, torsade de pointes, severe hypertension, and exacerbation of manic symptoms resulting from an overdose of compound licorice tablets. This study aimed to enhance the understanding of the causes of hypokalemia and raise awareness on the potentially fatal adverse reactions associated with licorice drugs.

Application of Monoclonal Antibodies against Naturally Occurring Bioactive Ingredients

Monoclonal antibodies (Mabs) are widely used in a variety of fields, including protein identification, life sciences, medicine, and natural product chemistry. This review focuses on Mabs against naturally occurring active compounds. The preparation of Mabs against various active compounds began in the 1980s, and now there are fewer than 50 types. Eastern blotting, which was developed as an antibody staining method for low-molecular-weight compounds, is useful for its ability to visually represent specific components. In this method, a mixture of lower-molecular-weight compounds, particularly glycosides, are separated by thin-layer chromatography (TLC). The compounds are then transferred to a membrane by heating, followed by treatment with potassium periodate (KIO4) to open the sugar moiety of the glycoside on the membrane to form an aldehyde group. Proteins are then added to form Schiff base bonds to enable adsorption on the membrane. A Mab is bound to the glycoside moiety on the membrane and reacts with a secondary antibody to produce color. Double Eastern blotting, which enables the simultaneous coloration of two glycosides, can be used to evaluate quality and estimate pharmacological effects. An example of staining by Eastern blotting and a component search based on the results will also be presented. A Mab-associated affinity column is a method for isolating antigen molecules in a single step. However, the usefulness of the wash fractions that are not bound to the affinity column is unknown. Therefore, we designated the wash fraction the "knockout extract". Comparing the nitric oxide (NO) production of a glycyrrhizin (GL)-knockout extract of licorice with a licorice extract revealed that the licorice extract is stronger. Therefore, the addition of GL to the GL-knockout extract of licorice increased NO production. This indicates that GL has synergic activity with the knockout extract. The GL-knockout extract of licorice inhibited high-glucose-induced epithelial-mesenchymal transition in NRK-52E cells, primarily by suppressing the Notch2 pathway. The real active constituent in licorice may be constituents other than GL, which is the causative agent of pseudohyperaldosteronism. This suggests that a GL-knockout extract of licorice may be useful for the treatment of diabetic nephritis.

Treatment with Glycyrrhiza glabra Extract Induces Anxiolytic Effects Associated with Reduced Salt Preference and Changes in Barrier Protein Gene Expression

We have previously identified that low responsiveness to antidepressive therapy is associated with higher aldosterone/cortisol ratio, lower systolic blood pressure, and higher salt preference. Glycyrrhiza glabra (GG) contains glycyrrhizin, an inhibitor of 11β-hydroxysteroid-dehydrogenase type-2 and antagonist of toll-like receptor 4. The primary hypothesis of this study is that food enrichment with GG extract results in decreased anxiety behavior and reduced salt preference under stress and non-stress conditions. The secondary hypothesis is that the mentioned changes are associated with altered gene expression of barrier proteins in the prefrontal cortex. Male Sprague-Dawley rats were exposed to chronic mild stress for five weeks. Both stressed and unstressed rats were fed a diet with or without an extract of GG roots for the last two weeks. GG induced anxiolytic effects in animals independent of stress exposure, as measured in elevated plus maze test. Salt preference and intake were significantly reduced by GG under control, but not stress conditions. The gene expression of the barrier protein claudin-11 in the prefrontal cortex was increased in control rats exposed to GG, whereas stress-induced rise was prevented. Exposure to GG-enriched diet resulted in reduced ZO-1 expression irrespective of stress conditions. In conclusion, the observed effects of GG are in line with a reduction in the activity of central mineralocorticoid receptors. The treatment with GG extract or its active components may, therefore, be a useful adjunct therapy for patients with subtypes of depression and anxiety disorders with heightened renin-angiotensin-aldosterone system and/or inflammatory activity.

Analysis of clinical factors associated with Kampo formula-induced pseudoaldosteronism based on self-reported information from the Japanese Adverse Drug Event Report database

Drug-induced pseudoaldosteronism is a typical adverse effect of Kampo formulas. Previous research described the potential risks of Kampo formula-linked pseudoaldosteronism. However, few studies assessed the risk factors using a real-world database and a data-mining approach. Using the Japanese Adverse Drug Event Report database, we extracted pseudoaldosteronism reports for 148 Kampo formulas covered by Japanese national health insurance. Adverse events were decided according to the preferred terminology of the Medical Dictionary for Regulatory Activities/Japanese version 25.1. We calculated reporting odds ratio (RORs) and identified Kampo formulas as suspected causes of pseudoaldosteronism. Moreover, we evaluated clinical factors associated with Kampo formula-induced pseudoaldosteronism via logistic regression. From April 2004 to November 2022, 6334 adverse events related to the Kampo formulas were reported. We selected 2471 reports containing complete clinical data, including 210 reports on pseudoaldosteronism. In the pseudoaldosteronism group, 69.0% of patients were female, and 85.2% were ≥70 years old. The formulas most commonly associated with pseudoaldosteronism were Shakuyakukanzoto, Yokukansan, and Ryokeijutsukanto (ROR [95% confidence interval {CI}] = 18.3 [13.0-25.9], 8.1 [5.4-12.0], and 5.5 [1.4-21.9], respectively). Logistic analysis identified female sex (odds ratio [OR] [95% CI] = 1.7 [1.2-2.6]; P = 0.006), older age (≥70, 5.0 [3.2-7.8]; P < 0.001), low body weight (<50 kg, 2.2 [1.5-3.2]; P < 0.001), diuretics usage (2.1 [1.3-4.8]; P = 0.004), hypertension (1.6 [1.1-2.4]; P = 0.014), and dementia (7.0 [4.2-11.6]; P < 0.001) as pseudoaldosteronism-related factors. Additionally, the daily Glycyrrhiza dose (OR = 2.1 [1.9-2.3]; P < 0.001) and duration of administration (>14 days, OR = 2.8 [1.7-4.5]; P < 0.001) were associated with adverse events. We did not observe an interaction between aging and hypertension. Careful follow-up is warranted during long-term Glycyrrhiza-containing Kampo formula use in patients with multiple clinical factors for pseudoaldosteronism.

Kampo medicines for supportive care of patients with cancer: A brief review

Background

Methods

Results

Conclusion

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.

Modulation of 11β-hydroxysteroid dehydrogenase functions by the cloud of endogenous metabolites in a local microenvironment: The glycyrrhetinic acid-like factor (GALF) hypothesis

11β-Hydroxysteroid dehydrogenase (11β-HSD)-dependent conversion of cortisol to cortisone and corticosterone to 11-dehydrocorticosterone are essential in regulating transcriptional activities of mineralocorticoid receptors (MR) and glucocorticoid receptors (GR). Inhibition of 11β-HSD by glycyrrhetinic acid metabolites, bioactive components of licorice, causes sodium retention and potassium loss, with hypertension characterized by low renin and aldosterone. Essential hypertension is a major disease, mostly with unknown underlying mechanisms. Here, we discuss a putative mechanism for essential hypertension, the concept that endogenous steroidal compounds acting as glycyrrhetinic acid-like factors (GALFs) inhibit 11β-HSD dehydrogenase, and allow for glucocorticoid-induced MR and GR activation with resulting hypertension. Initially, several metabolites of adrenally produced glucocorticoids and mineralocorticoids were shown to be potent 11β-HSD inhibitors. Such GALFs include modifications in the A-ring and/or at positions 3, 7 and 21 of the steroid backbone. These metabolites may be formed in peripheral tissues or by gut microbiota. More recently, metabolites of 11β-hydroxy-Δ4androstene-3,17-dione and 7-oxygenated oxysterols have been identified as potent 11β-HSD inhibitors. In a living system, 11β-HSD isoforms are not exposed to a single substrate but to several substrates, cofactors, and various inhibitors simultaneously, all at different concentrations depending on physical state, tissue and cell type. We propose that this "cloud" of steroids and steroid-like substances in the microenvironment determines the 11β-HSD-dependent control of MR and GR activity. A dysregulated composition of this cloud of metabolites in the respective microenvironment needs to be taken into account when investigating disease mechanisms, for forms of low renin, low aldosterone hypertension.