Clinicopathological features of Bu Gu Zhi-induced liver injury, a long-term follow-up cohort study

Bavachinin causes cholestasis by down-regulating BAAT expression and disrupting glycocholic acid synthesis in human liver organoids

Psoraleae Fructus (Bu Gu Zhi, BGZ) is extensively utilized for dermatological and osseous disorders in China. BGZ-induced liver injury has become one of the major concerns, which predominantly cause cholestasis, with the pathogenesis not being fully elucidated. Currently, studies on hepatotoxic mechanisms of BGZ have mainly been conducted on 2D cell culture systems or rodent models, which may not fully encapsulate human pathophysiology. Therefore, we generated human liver organoids (HLOs) from healthy donor(s) for living-related liver transplantation to explore the hepatotoxic mechanism. We identified bavachinin (BVC) as the most hepatotoxic component for cholestasis. After validating by CLF tests, we identified BVC caused cholestasis by down-regulating BAAT, which catalyzes the amidation of bile acids. We also found that up-regulating BAAT with harmaline could mitigate cholestasis and enhance cell viabilities in HLOs. We further demonstrated that glycocholic acid (GCA) levels decreased in BVC-treated HLOs. Supplementation of GCA to BVC-treated HLOs significantly improved cell viabilities. Collectively, our data suggested that BVC impaired the GCA synthesis by down-regulating the expression of BAAT, thereby inducing cholestasis.

Psoraleae Fructus affects the livers of normal and ulcerative colitis rats differently by altering bile acid metabolism

ETHNOPHARMACOLOGICAL RELEVANCE

Psoraleae Fructus (PF), the dried mature fruit of the leguminous plant Psoralea corylifolia L., is often used as a nutraceutical and to treat ulcerative colitis (UC). However, recently there have been reports of PF-induced liver injury.

AIM OF THE STUDY

To investigate the difference and mechanism of hepatotoxicity between normal and UC rats oral administration with PF, and clarify the relationship between PF risk and disease status.

MATERIALS AND METHODS

PF water extracts (at the human equivalent dosage and 8-fold greater; 0.7 and 5.6 g/kg/day, respectively) were given to normal and UC rats for 4 weeks, and the general behaviors and colonic mucosal conditions were observed. The liver injury and its mechanism were studied by blood biochemistry, coagulation time, liver hematoxylin and eosin (H&E) staining, bile acids (BAs) metabolism, transcriptome analysis, quantitative real-time polymerase chain reaction (qRT‒PCR) and western blot (WB)experiments.

RESULTS

Normal rats receiving 5.6 g/kg PF water extract showed significantly increased serum levels of total bilirubin (TBIL) and total bile acids (TBA), significantly prolonged activated partial thromboplastin time (APTT), prothrombin time (PT) and thromboplastin time (TT), and slightly swollen hepatocytes, and obvious hepatobiliary hyperplasia. These liver injuries may be related to disordered BAs metabolism: the levels of farnesoid x receptor (FXR) and sulfotransferase family 2A member 1/2 (SULT2a1/a2) were down-regulated, whereas the levels of microsomal epoxide hydrolase (mEH), organic anion transporting polypeptide (OATP) and multidrug resistance-associated protein 3 (MRP3) were up-regulated, leading to liver and blood UnconBA and GlycineBA accumulation. However, at the same dose, UC model rats exhibited no obvious liver damage.

CONCLUSION

Normal rats, but not UC rats, displayed signs of liver injury in response to 5.6 g/kg PF water extract administration. Therefore, we recommend that healthy individuals should be aware of the potential risks associated with PF, and other patients should take PF according to their physician's guidance.

Exploring the anti-inflammatory and immunomodulatory potential of licochalcone B against psoralidin-induced liver injury

ETHNOPHARMACOLOGICAL RELEVANCE

Herb-induced liver injury (HILI) represents an exacerbated inflammatory response, with Psoraleae fructus (PF) and its preparations recently associated with hepatotoxicity. Licorice, historically recognized as a detoxifying herbal remedy, is considered to possess hepatoprotective properties. Our previous research identified bavachin, bakuchiol, and psoralidin (PSO) as potential toxic constituents in PF, while licochalcone B (LCB) and echinatin were identified as bioactive components in licorice. However, evidence regarding the interactions of active compounds in herbs and their underlying mechanisms remains limited.

AIM OF THE STUDY

The objective of this study is to assess the potential mechanisms through which LCB modulates immunological and anti-inflammatory responses to treat PSO-induced liver injury by using human hepatocyte cells (L02) and LPS-primed mice.

METHODS

The ameliorative effects of LCB and echinatin on bavachin, bakuchiol, and PSO-induced liver injury were demonstrated in L02 cells. Subsequently, the efficacy of LCB on PSO-induced idiosyncratic liver injury was further validated in C57BL/6 mice under moderate inflammatory stress induced by LPS priming. The mechanisms were preliminarily explored with an integrated strategy of molecular docking, RT-PCR verification, and untargeted metabolomics.

RESULTS

The study shows that LCB significantly reduced cell injury induced by the three chemicals in PF and provided substantial protection against PSO-induced hepatic damage, as indicated by the levels of ALT, AST, and LDH. LCB normalized liver function and remarkedly alleviated hepatic lesions and inflammation caused by PSO in mice under moderate inflammatory stress. The mRNA profiles of both L02 cells and mice liver tissue revealed that LCB mitigated PSO-induced hepatotoxicity by regulating the gene expression of pro-inflammatory cytokines IL1B and TNF, as well as immunoinflammatory genes PIK3CA, AKT1, NFKB1, and NLRP3. Furthermore, untargeted metabolomics of liver tissue indicated that LCB could reverse the abnormal expression of 11 discriminatory metabolites, with the interrelationship between differential metabolites and target genes primarily clustering in glycerophospholipid metabolism, arachidonic acid metabolism, and phosphatidylinositol signaling system.

CONCLUSION

LCB demonstrated a superior anti-inflammatory and immunomodulatory effect on PSO-induced hepatotoxicity by modulating the inflammatory response and metabolic signaling system. Key interactive targets included phosphatidylcholine, phosphatidic acid, and subunit isoforms of PI3K.

Characterizing metabolomic and transcriptomic changes, and investigating the therapeutic mechanism of Psoralea corylifolia linn. In the treatment of kidney-yang deficiency syndrome in rats

Kidney-yang deficiency syndrome (KYDS) is characterized by a metabolic disorder stemming from neuroendocrine dysregulation, often associated with hepatic dysfunction. In traditional Chinese medicine, Psoralea corylifolia Linn. (BGZ) is commonly utilized for treating KYDS. However, the specific therapeutic effects of BGZ on liver function regulation remain unclear. To evaluate the protective effects of BGZ against KYDS in rats, organ index, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and other biochemical indices were analyzed. Hematoxylin and eosin (HE) staining was utilized to assess liver histopathology. Additionally, transcriptomic and metabolomic analyses were conducted to identify potential biomarkers. BGZ treatment led to a significant reduction in ALT and AST levels, accompanied by improvements in liver histopathology in rats with KYDS. Moreover, BGZ induced significant alterations in 92 differentially expressed genes (DEGs) and 20 metabolites in the KYDS rat model. The comprehensive examination of metabolites and DEGs identified potential mechanisms underlying the therapeutic effects of BGZ, highlighting the neuroactive ligand-receptor interaction, cAMP signaling pathway, calcium signaling pathway, and cytokine-cytokine receptor interaction as key mechanisms. Validation of key targets within the cAMP pathway was substantiated through enzyme-linked immunosorbent assay and real-time quantitative polymerase chain reaction. The cAMP pathway emerges as a plausible mechanism through which BGZ exerts protective effects against KYDS. The findings of this study contribute to an improved understanding of the therapeutic actions of BGZ and establish a groundwork for further research into the complex pathways involved, as well as the potential for drug-targeted therapies for KYDS.

NLRP3 inflammasome in hepatic diseases: A pharmacological target

The NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome pathway is mainly responsible for the activation and release of a cascade of proinflammatory mediators that contribute to the development of hepatic diseases. During alcoholic liver disease development, the NLRP3 inflammasome pathway contributes to the maturation of caspase-1, interleukin (IL)-1β, and IL-18, which induce a robust inflammatory response, leading to fibrosis by inducing profibrogenic hepatic stellate cell (HSC) activation. Substantial evidence demonstrates that nonalcoholic fatty liver disease (NAFLD) progresses to nonalcoholic steatohepatitis (NASH) via NLRP3 inflammasome activation, ultimately leading to fibrosis and hepatocellular carcinoma (HCC). Activation of the NLRP3 inflammasome in NASH can be attributed to several factors, such as reactive oxygen species (ROS), gut dysbiosis, leaky gut, which allow triggers such as cardiolipin, cholesterol crystals, endoplasmic reticulum stress, and uric acid to reach the liver. Because inflammation triggers HSC activation, the NLRP3 inflammasome pathway performs a central function in fibrogenesis regardless of the etiology. Chronic hepatic activation of the NLRP3 inflammasome can ultimately lead to HCC; however, inflammation also plays a role in decreasing tumor growth. Some data indicate that NLRP3 inflammasome activation plays an important role in autoimmune hepatitis, but the evidence is scarce. Most researchers have reported that NLRP3 inflammasome activation is essential in liver injury induced by a variety of drugs and hepatotropic virus infection; however, few reports indicate that this pathway can play a beneficial role by inducing liver regeneration. Modulation of the NLRP3 inflammasome appears to be a suitable strategy to treat liver diseases.

A gene expression profile-based approach to screen the occurrence and predisposed host characteristics of drug-induced liver injury: a case study of Psoralea corylifolia Linn

Drug-induced liver injury (DILI) is one of the most common causes of a drug being withdrawn, and identifying the culprit drugs and the host factors at risk of causing DILI has become a current challenge. Recent studies have found that immune status plays a considerable role in the development of DILI. In this study, DILI-related differentially expressed genes mediated by immunoinflammatory cytokines were obtained from the Gene Expression Omnibus (GEO) database to predict the occurrence of DILI (named the DILI predictive gene set, DILI_PGS), and the predictability of the DILI_PGS was verified using the Connectivity Map (CMap) and LiverTox platforms. The results obtained DILI_PGS from the GEO database could predict 81.25% of liver injury drugs. In addition, the Coexpedia platform was used to predict the DILI_PGS-related characteristics of common host diseases and found that the DILI_PGS mainly involved immune-related diseases and tumor-related diseases. Then, animal models of immune stress (IS) and immunosuppressive (IP) were selected to simulate the immune status of the above diseases. Meanwhile, psoralen, a main component derived from Psoralea corylifolia Linn. with definite hepatotoxicity, was selected as an experimental drug with highly similar molecular fingerprints to three idiosyncratic hepatotoxic drugs (nefazodone, trovafloxacin, and nimesulide) from the same DILI_PGS dataset. The animal experiment results found a single administration of psoralen could significantly induce liver injury in IS mice, while there was no obvious liver function change in IP mice by repeatedly administering the same dose of psoralen, and the potential mechanism of psoralen-induced liver injury in IS mice may be related to regulating the expression of the TNF-related pathway. In conclusion, this study constructed the DILI_PGS with high accuracy to predict the occurrence of DILI and preliminarily identified the characteristics of host factors inducing DILI.

Yin/Yang associated differential responses to Psoralea corylifolia Linn. In rat models: an integrated metabolomics and transcriptomics study

ETHNOPHARMACOLOGICAL RELEVANCE

Psoralea corylifolia Linn. (BGZ) is a commonly used traditional Chinese medicine (TCM) for the treatment of kidney-yang deficiency syndrome (Yangsyn) with good curative effect and security. However, BGZ was also reported to induce liver injury in recent years. According to TCM theory, taking BGZ may induce a series of adverse reactions in patients with kidney-yin deficiency syndrome (Yinsyn), which suggests that BGZ-induced liver damage may be related to its unreasonable clinical use.

AIM OF THE STUDY

Liver injury caused by TCM is a rare but potentially serious adverse drug reaction, and the identification of predisposed individuals for drug-induced liver injury (DILI) remains challenging. The study aimed to investigate the differential responses to BGZ in Yangsyn and Yinsyn rat models and identify the corresponding characteristic biomarkers.

MATERIALS AND METHODS

The corresponding animal models of Yangsyn and Yinsyn were induced by hydrocortisone and thyroxine + reserpine respectively. Body weight, organ index, serum biochemistry, and Hematoxylin and Eosin (HE) staining were used to evaluate the liver toxicity effect of BGZ on rats with Yangsyn and Yinsyn. Transcriptomics and metabonomics were used to screen the representative biomarkers (including metabolites and differentially expressed genes (DEGs)) changed by BGZ in Yangsyn and Yinsyn rats, respectively.

RESULTS

The level changes of liver organ index, alanine aminotransferase (ALT), and aspartate aminotransferase (AST), suggested that BGZ has liver-protective and liver-damaging effects on Yangsyn and Yinsyn rats, respectively, and the results also were confirmed by the pathological changes of liver tissue. The results showed that 102 DEGs and 27 metabolites were significantly regulated related to BGZ's protective effect on Yangsyn, which is mainly associated with the glycerophospholipid metabolism, arachidonic acid metabolism, pantothenate, and coenzyme A (CoA) biosynthesis pathways. While 28 DEGs and 31 metabolites, related to the pathway of pantothenate and CoA biosynthesis, were significantly regulated for the BGZ-induced liver injury in Yinsyn. Furthermore, 4 DEGs (aldehyde dehydrogenase 1 family member B1 (Aldh1b1), solute carrier family 25 member 25 (Slc25a25), Pim-3 proto-oncogene, serine/threonine kinase (Pim3), out at first homolog (Oaf)) and 4 metabolites (phosphatidate, phosphatidylcholine, N-Acetylleucine, biliverdin) in the Yangsyn group and 1 DEG [galectin 5 (Lgals5)] and 1 metabolite (5-amino-1-(5-phospho-D-ribosyl)imidazole-4-carboxylate) in Yinsyn group were significantly correlated to the ALT and AST levels of BGZ treated and untreated groups (receiver operating characteristic (ROC) ≥ 0.9).

CONCLUSIONS

Yinsyn and Yangsyn are the predisposed syndromes for BGZ to exert liver damage and liver protection respectively, which are mainly related to the regulation of amino acid metabolism, lipid metabolism, energy metabolism, and metabolism of cofactors and vitamins. The results further suggest that attention should be paid to the selection of predisposed populations when using drugs related to the regulation of energy metabolism, and the Yinsyn/Yangsyn animal models based on the theory of TCM syndromes may be a feasible method for identifying the susceptible population to receive TCM.

4-hydroxylonchocarpin and corylifol A: The potential hepatotoxic components of Psoralea corylifolia L

Psoralea corylifolia L. (P. corylifolia) has attracted increasing attention because of its potential hepatotoxicity. In this study, we used network analysis (toxic component and hepatotoxic target prediction, proteinprotein interaction, GO enrichment analysis, KEGG pathway analysis, and molecular docking) to predict the components and mechanism of P. corylifolia-induced hepatotoxicity and then selected 4-hydroxylonchocarpin and corylifol A for experimental verification. HepG2 cells were treated with low, medium, and high concentrations of 4-hydroxylonchocarpin or corylifol A. The activities of ALT, AST, and LDH in cell culture media and the MDA level, SOD activity, and GSH level in cell extracts were measured. Moreover, apoptosis, ROS levels, and mitochondrial membrane potential were evaluated. The results showed that the activities of ALT, AST, and LDH in the culture medium increased, and hepatocyte apoptosis increased. The level of MDA increased, and the activity of SOD and level of GSH decreased, and the ROS level increased with 4-hydroxylonchocarpin and corylifol A intervention. Furthermore, the mitochondrial membrane potential decreased in the 4-hydroxylonchocarpin and corylifol A groups. This study suggests that 4-hydroxylonchocarpin and corylifol A cause hepatocyte injury and apoptosis by inducing oxidative stress and mitochondrial dysfunction, suggesting that these compounds may be the potential hepatotoxic components of P. corylifolia.

The acute oral toxicity test of ethanol extract of salt-processed Psoraleae Fructus and its acute hepatotoxicity and nephrotoxicity risk assessment

ETHNOPHARMACOLOGICAL RELEVANCE

Psoraleae Fructus is a well-known Traditional Chinese Medicine which has long been used to warm and tonify the kidney and treat diseases such as osteoporosis and diarrhea. However, it may cause multiorgan injury, which limited its use.

AIM OF THE STUDY

The aim of this study was to identify the components of ethanol extract of salt-processed Psoraleae Fructus (EEPF) and systematically investigate its acute oral toxicity and the mechanism underlying its acute hepatotoxicity.

MATERIALS AND METHODS

In this study, the UHPLC-HRMS analysis was carried out for components identification. Followed by acute oral toxicity test in Kunming mice, which received oral gavage of EEPF from 3.85 to 78.00 g/kg. Body weight, organ indexes, biochemical analysis, morphology, histopathology, oxidative stress state, TUNEL, mRNA and protein expression of NLRP3/ASC/Caspase-1/GSDMD signaling pathway were evaluated to study the EEPF-induced acute hepatotoxicity and its underlying mechanisms.

RESULTS

The results showed that 107 compounds such as psoralen and isopsoralen were identified in EEPF. And the acute oral toxicity test demonstrated the LD₅₀ of EEPF was 15.95 g/kg in Kunming mice. The survival mice displayed non-significant difference in body weight compared with Control at the end of the observation period. And the organ indexes of heart, liver, spleen, lung, and kidney showed no significant difference. However, the morphological and histopathological changes of these organs in high-dose-groups mice indicated that the liver and kidney might be the main target toxic organs of EEPF, which showed hepatocyte degeneration with lipid droplets and protein cast in kidney. It could be confirmed by the significant increases of liver and kidney function parameters such as AST, ALT, LDH, BUN, and Crea. In addition, the oxidative stress markers, MDA in the liver and kidney was significantly increased while SOD, CAT, GSH-Px (only liver), and GSH were significantly decreased. Furthermore, EEPF increased the TUNEL-positive cells and the mRNA and protein expression of NLRP3, Caspase-1, ASC and GSDMD in liver with increased protein expression of IL-1β and IL-18. Notably, cell viability test showed that the specific inhibitor of Caspase-1 could reverse the Hep-G2 cell death induced by EEPF.

CONCLUSION

To summarize, this study analyzed the 107 compounds of EEPF. The acute oral toxicity test demonstrated the LD₅₀ value of EEPF was 15.95 g/kg in Kunming mice and the liver and kidney might be the main target toxic organs of EEPF. It caused liver injury through oxidative stress and pyroptotic damage via NLRP3/ASC/Caspase-1/GSDMD signaling pathway.

Unveiling hepatotoxicity distinction of coumarin-related compounds from glycosides to aglycones in Fructus Psoraleae by integrating UPLC-Q-TOF-MS and high content analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Fructus Psoraleae (FP), the dried and ripe fruit of Cullen corylifolium (L.) Medik., is widely used due to its various clinical pharmacological effects, but its hepatotoxicity restricts its clinical application. So far, its hepatotoxic components and their underlying mechanism have not been systematically elucidated.

AIM OF THE STUDY

This study was undertaken to reveal the hepatotoxicity distinction of coumarin-related compounds from glycosides to aglycones in FP and elucidate their potential mechanism.

METHODS

Rats were administrated with the aqueous extract of Fructus Psoraleae (AEFP), in which eight coumarin-related compounds were focused. Subsequently, compounds exposed in rats' livers were detected by UPLC-Q-TOF-MS, and the identified hepatotoxic compounds were evaluated to elaborate their possible mechanism by the aid of high content analysis (HCA).

RESULTS

Eight coumarin-related compounds were identified, among which psoralenoside (PO), isopsoralenoside (IPO), psoralen (P), and isopsoralen (IP) were the principally exposed compounds in rats' livers. Furocoumarinic acid glucoside (FAG), (E)-3-(4-(((2S, 3R, 4S, 5S, 6R)-3,4,5-trihydroxy-6-(hydroxymethyl) tetrahydro-2H-pyran-2-yl) oxy) benzofuran-5-yl) acrylic acid (isofurocoumarinic acid glucoside, IFAG), furocoumarinic acid (FA), and (E)-3-(4-hydroxybenzofuran-5-yl) acrylic acid (isofurocoumarinic acid, IFA) were also detected in low abundance. P, IP, FA, and IFA were identified as the hepatotoxic compounds, while their glycosides were almost non-hepatotoxic. The HCA's results showed that hepatotoxic compounds disrupted the balance in reactive oxygen species (ROS), nuclear area, and mitochondrial membrane potential of HepG2 cells, leading to the occurrence of hepatotoxicity.

CONCLUSIONS

P, IP, FA, and IFA were identified as hepatotoxic compounds, from which P and IP were proposed as the important risk components for hepatotoxicity. The conversion from glycosides to aglycones played an essential role in FP-induced hepatotoxicity.

Inhibition of estrogen sulfation by Xian-Ling-Gu-Bao capsule

Xian-Ling-Gu-Bao capsule (XLGB) is a widely prescribed traditional Chinese medicine used for the treatment of osteoporosis. However, it significantly elevates levels of serum estrogens. Here we aimed to assess the dominant contributors of sulfotransferase (SULT) enzymes to the sulfation of estrogens and identify the effective inhibitors of this pathway in XLGB. First, estrone, 17β-estradiol, and estriol underwent sulfation in human liver S9 extracts. Phenotyping reactions and enzyme kinetics assays revealed that SULT1A1, 1A2, 1A3, 1C4, 1E1, and 2A1 all participated in estrogen sulfation, with SULT1E1 and 1A1 as the most important contributors. The incubation system for these two active enzymes were optimized with Tris-HCl buffer, DL-Dithiothreitol (DTT), MgCl₂, adenosine 3'-phosphate 5'-phosphosulfate (PAPS), protein concentration, and incubation time. Then, 29 compounds in XLGB were selected to investigate their inhibitory effects and mechanisms against SULT1E1 and 1A1 through kinetic modelling. Moreover, in silico molecular docking was used to validate the obtained results. And finally, the prenylated flavonoids (isobavachin, neobavaisoflavone, etc.) from Psoralea corylifolia L., prenylated flavanols (icariside II) from Epimedium brevicornu Maxim., tanshinones (dihydrotanshinone, tanshinone II-A,) from Salvia miltiorrhiza Bge., and others (corylifol A, corylin) were identified as the most potent inhibitors of estrogen sulfation. Taken together, these findings provide insights into the understanding regioselectivity of estrogen sulfation and identify the effective components of XLGB responsible for the promotion of estrogen levels.

Transcriptomics and metabolomics reveal the role of CYP1A2 in psoralen/isopsoralen-induced metabolic activation and hepatotoxicity

Psoralen and isopsoralen are the pharmacologically important but hepatotoxic components in Psoraleae Fructus. The purpose of this study was to reveal the underlying mechanism of psoralen/isopsoralen-induced hepatotoxicity. Initially, we applied integrated analyses of transcriptomic and metabolomic profiles in mice treated with psoralen and isopsoralen, highlighting the xenobiotic metabolism by cytochromes P450 as a potential pathway. Then, with verifications of expression levels by qRT-PCR and western blot, affinities by molecular docking, and metabolic contributions by recombinant human CYP450 and mouse liver microsomes, CYP1A2 was screened out as the key metabolic enzyme. Afterwards, CYP1A2 induction and inhibition models in HepG2 cells and mice were established to verify the role of CYP1A2, demonstrating that induction of CYP1A2 aggravated the hepatotoxicity, and conversely inhibition alleviated the hepatotoxic effects. Additionally, we detected glutathione adducts with reactive intermediates of psoralen and isopsoralen generated by CYP1A2 metabolism in biosystems of recombinant human CYP1A2 and mouse liver microsomes, CYP1A2-overexpressed HepG2 cells, mice livers and the chemical reaction system using UPLC-Q-TOF-MS/MS. Ultimately, the high-content screening presented the cellular oxidative stress and relevant hepatotoxicity due to glutathione depletion by reactive intermediates. In brief, our findings illustrated that CYP1A2-mediated metabolic activation is responsible for the psoralen/isopsoralen-induced hepatotoxicity.

Discovery of bakuchiol as an AIM2 inflammasome activator and cause of hepatotoxicity

ETHNOPHARMACOLOGICAL RELEVANCE

Psoralea corylifolia (P. corylifolia Linn.) is a traditional Chinese medicinal plant that exhibits significant aphrodisiac, diuretic, and anti-rheumatic effects. However, it has been reported to cause hepatic injury, but the precise mechanisms remain unclear.

AIM OF THE STUDY

To evaluate the safety and risk of P. corylifolia and to elucidate the underlying mechanisms of drug-induced liver injury.

MATERIALS AND METHODS

Western blotting, enzyme-linked immunosorbent assay (ELISA), immunofluorescence, quantitative polymerase chain reaction (Q-PCR), and flow cytometry were used to explore the effect of bakuchiol (Bak), one of the most abundant and biologically active components of P. corylifolia, on the AIM2 inflammasome activation and the underlying mechanism. Furthermore, we used the lipopolysaccharides (LPS)-induced drug-induced liver injury (DILI) susceptible mice model to study the Bak-mediated hepatotoxicity.

RESULTS

Bak induced the maturation of caspase-1 P20, and significantly increased the expression of IL-1β and TNF-α (P < 0.0001) compared with the control group. Moreover, compared to the Bak group, knockdown of AIM2 inhibited Bak-induced caspase-1 maturation and significantly decreased the production of IL-1β and TNF-α, but knockout of NLRP3 had no effect. Mechanistically, Bak-induced AIM2 inflammasome activation is involved in mitochondrial damage, mitochondrial DNA (mtDNA) release, and subsequent recognition of cytosolic mtDNA. Our in vivo data showed that co-exposure to LPS and non-hepatotoxic doses of Bak significantly increased the levels of ALT, AST, IL-1β, TNF-α, and IL-18, indicating that Bak can induce severe liver inflammation (P < 0.005).

CONCLUSIONS

The result shows that Bak activates the AIM2 inflammasome by inducing mitochondrial damage to release mtDNA, and subsequently binds to the AIM2 receptor, indicating that Bak may be a risk factor for P. corylifolia-induced hepatic injury.

Comparison of the prognostic models for mortality in idiosyncratic drug-induced liver injury

BACKGROUND

Several models have been proposed to predict acute liver failure/death in patients with drug-induced liver injury (DILI), but the predictive performances of them have not been systematically compared. We aim to compare the current models for their predictive potency of mortality at DILI onset.

METHODS

DILI patients hospitalized at both Beijing Friendship Hospital and the Fifth Medical Center of PLA General Hospital were categorized into death/liver transplantation (LT) or survival without LT group. Predictive potency of 28-day, 90-day, 6-month and 12-month death/LT outcomes of Hy's Law, nHy's Law, Robles-Diaz Model, drug-induced liver toxicity (DrILTox ALF) Score, Model for End-stage Liver Disease (MELD) Score, and Ghabril Model was compared by Delong method.

RESULTS

A total of 6.3% (83/1314) patients died or received LT within 12 months after DILI onset. The area under receiver operating characteristic of Hy's Law, nHy's Law, and Robles-Diaz Model was all lower than 0.750 for the prediction of within 12 months' mortality. DrILTox ALF Score, MELD Score and Ghabril Model showed better predictive potency of 28-day [0.896 (0.878-0.912), 0.934 (0.919-0.947), 0.935 (0.921-0.948), respectively], 90-day [0.883 (0.864-0.899), 0.951 (0.938-0.962), 0.952 (0.939-0.963), respectively], 6-month [0.820 (0.799-0.841), 0.905 (0.888-0.921) and 0.908 (0.891-0.923), respectively] and 12-month [0.801 (0.779-0.823), 0.882 (0.863-0.899) and 0.885 (0.866-0.902), respectively] mortality.

CONCLUSION

Despite the difference of clinical characteristics and implicated-drug categories between China and industrialized countries, we demonstrate that MELD Score and Ghabril Model have the best predictive performance in the prediction of mortality within 12 months after DILI onset.

Psoralen and isopsoralen from Psoraleae Fructus aroused hepatotoxicity via induction of aryl hydrocarbon receptor-mediated CYP1A2 expression

ETHNOPHARMACOLOGICAL RELEVANCE

Psoraleae Fructus (PF), a traditional Chinese medicine, has long been used to treat diseases such as cancer, osteoporosis and leukoderma. Psoralen and isopsoralen are main bioactive ingredients of PF with anti-tumor, anti-inflammatory, estrogen-like neuroprotection, etc., meanwhile they are also representative hepatotoxic components of PF. Hepatic CYP1A2 has been reported to be the important metabolic enzymes involved in psoralen and isopsoralen-induced hepatotoxicity. However, the relationship between the hepatotoxicity and CYP1A2 expression, and the underlying mechanism of regulating CYP1A2 expression remain unclear.

AIM OF STUDY

The aim of this study was to explore the associated mechanism between psoralen or isopsoralen induced hepatotoxicity and activated aryl hydrocarbon receptor (AhR)-mediated transcriptional induction of CYP1A2 in vitro and in vivo.

MATERIALS AND METHODS

Psoralen and isopsoralen at different doses were treated on HepG2 cells (10, 25, 50, 100, 200 μM for 2, 12, 24, 36, 48 h) and mice (20, 80, 160 mg/kg for 3, 7, 14 days) for different time, to assess the correlation of induced hepatotoxicity and CYP1A2 mRNA and protein expression in vivo and in vitro, as well as the effect on CYP1A2 enzyme activity evaluated by phenacetin metabolism. In addition, the potential mechanism of the regulation of CYP1A2 expression mediated by AhR was explored through nucleocytoplasmic shuttling, immunofluorescence, cellular thermal shift assay and molecular docking, etc. RESULTS: Psoralen and isopsoralen induced cytotoxicity in HepG2 cells, and hepatomegaly, biochemicals disorder and tissue pathological impairment in mice, respectively in dose- and time-dependent manners. Simultaneously accompanied with elevated levels of CYP1A2 mRNA and protein in the same trend, and the CYP1A2 activity was remarkably inhibited in vitro but significantly elevated overall in vivo. Besides, psoralen and isopsoralen bound to AhR and activated translocation of AhR from the cytoplasm to the nucleus, leading to the transcriptional induction of target gene CYP1A2.

CONCLUSIONS

Hepatotoxicities in HepG2 cells and mice aroused by psoralen and isopsoralen were related to the induction of CYP1A2 expression and activity, whose underlying mechanism might be psoralen or isopsoralen activated AhR translocation and induced increase of CYP1A2 transcriptional expression. Hopefully, these finding are conductive to propose an alert about the combined usage of psoralen or isopsoralen and AhR ligands or CYP1A2 substrates in clinical practice.

Identification of naturally occurring inhibitors in Xian-Ling-Gu-Bao capsule against the glucuronidation of estrogens

Xian-Ling-Gu-Bao (XLGB) capsule, a well-known traditional Chinese medicine prescription, is widely used for the treatment of osteoporosis. It could significantly increase the levels of estrogen in ovariectomized rats and mice. However, this working mechanism has not been well elucidated. Considering that UDP-glucuronosyltransferase (UGT) enzymes are the important enzymes that inactivate and regulate estrogen activity in vivo, this study aimed to identify the bioactive compounds from XLGB against the glucuronidation of estrogens. First, thirty compounds were considered as candidate bioactive compounds based on our previous studies including pharmacological evaluation, chemical profiles, and metabolic profiles. Second, the characteristics of estrogen glucuronidation by uridine diphosphate glucuronic acid (UDPGA)-supplemented human liver microsomes (HLM), human intestine microsomes (HIM), and expressed UGT enzymes were determined, and the incubation systems of their key UGT enzymes were optimized. Then, inhibitory effects and mechanisms of XLGB and its main compounds toward the key UGT isozymes were further investigated. As a result, estrogen underwent efficient glucuronidation by HLM and HIM. UGT1A10, 1A1, and 2B7 were mainly responsible for the glucuronidation of estrone, β-estradiol, and estriol, respectively. For E1 and E2, UGT1A10 and 1A1 tended to mediate estrogen-3-O-glucuronidation, while UGT2B7 preferred catalyzing estrogen-16-O-glucuronidation. Furthermore, the incubation system for active UGT isoforms was optimized including Tris-HCl buffer, detergents, MgCl2 concentration, β-glucuronidase inhibitors, UDPGA concentration, protein concentration, and incubation time. Based on optimal incubation conditions, eleven, nine, and nine compounds were identified as the potent inhibitors for UGT1A10, 1A1, and 2B7, respectively (IC50 &lt; 4.97 μM and Ki &lt; 3.35 μM). Among them, six compounds (bavachin, isobavachin, isobavachalcone, neobavaisoflavone, corylifol A, and icariside II) simultaneously demonstrated potent inhibitory effects against these three active enzymes. Prenylated flavanols from Epimedium brevicornu Maxim., prenylated flavonoids from Psoralea corylifolia L., and salvianolic acids from Salvia miltiorrhiza Bge. were characterized as the most important and effective compounds. The identification of potent natural inhibitors of XLGB against the glucuronidation of estrogen laid an important foundation for the pharmacodynamic material basis.

Multi-parametric cellular imaging coupled with multi-component quantitative profiling for screening of hepatotoxic equivalent markers from Psoraleae Fructus

BACKGROUND

The hepatotoxicity of Chinese herbal medicine (CHM) is an important reason for its restrictive application. Psoraleae Fructus (PF), a commonly used CHM for treatment of osteoporosis and vitiligo etc., has caused serious concern due to the frequent occurrence of liver injury incidents. To date, its hepatotoxic equivalent markers (HEMs) and potential mechanisms are still unclear.

PURPOSE

To discover and validate the HEMs of PF and further explore the potential mechanisms of hepatotoxicity.

METHODS

Multi-parametric cellular imaging was performed by high content screening, and multi-component quantitative profiling was conducted by ultra-high performance liquid chromatography coupled with triple-quadrupole mass spectrometry. The correlations between hepatotoxic features and component contents were modeled by chemometrics including partial least square regression, back propagation-artificial neural network, and hierarchical cluster analysis. Then the candidate HEMs of PF were screened out and subjected to hepatotoxic equivalence assessment in primary hepatocytes, zebrafish, and mice, and the hepatotoxic mechanisms of PF were investigated.

RESULTS

The chemical combination of psoralen and isopsoralen was discovered as the HEMs of PF through pre-screening and verifying process. PF was demonstrated to induce oxidative stress, mitochondrial dysfunction and cellular apoptosis.

CONCLUSIONS

This study not only provides a rational strategy for screening HEMs from CHMs like PF, but also contributes to understanding the underlying mechanisms of PF hepatotoxicity.

Herbal and dietary supplement induced liver injury: Highlights from the recent literature

Herbal-induced liver injury (HILI) is an important and increasingly concerning cause of liver toxicity, and this study presents recent updates to the literature. An extensive literature review was conducted encompassing September 2019 through March 2021. Studies with clinically significant findings were analyzed and included in this review. We emphasized those studies that provided a causality assessment methodology, such as Roussel Uclaf Causality Assessment Method scores. Our review includes reports of individual herbals, including Garcinia cambogia, green tea extract, kratom as well as classes such as performance enhancing supplements, Traditional Chinese medicine, Ayurvedic medicine and herbal contamination. Newly described herbals include ashwagandha, boldo, skyfruit, and 'Thermo gun'. Several studies discussing data from national registries, including the United States Drug-Induced Liver Injury (DILI) Network, Spanish DILI Registry, and Latin American DILI Network were incorporated. There has also been a continued interest in hepatoprotection, with promising use of herbals to counter hepatotoxicity from anti-tubercular medications. We also elucidated the current legal conversation surrounding use of herbals by presenting updates from the Federal Drug Administration. The highlights of the literature over the past year indicate interest in HILI that will continue as the supplement industry in the United States grows.

Signatures in drug-induced liver injury

PURPOSE OF REVIEW

Drug-induced liver injury (DILI) can be induced by a myriad of drugs. Assessing whether the patient has DILI and assessing which drug is the most likely culprit are challenging. There has been too little attention paid to the concept that certain drugs appear to have unique clinical features or 'phenotypes'.

RECENT FINDINGS

Several case series of DILI because of various drugs have been published, and analysis of these case series points to the fact that individual drugs have characteristic DILI signatures. These clinical phenotypes can be characterized by latency, biochemical features (R-value), as well as clinical symptoms and signs. Several drugs, including isoniazid, amoxicillin-clavulanic acid, anabolic steroids, β-interferon and others, have highly unique clinical features. Such unique properties may be able to be used to improve adjudication processes.

SUMMARY

Individual drugs have unique clinical DILI phenotypes or signatures. Furthermore, these may be able to be used to improve adjudication.