Long-term diosbulbin B treatment induced liver fibrosis in mice

New finding based on Comparative Toxicogenomics Database: Hepatic YY1 mediates drug-induced liver injury

BACKGROUND

YY1 plays a crucial part in the onset and progression of numerous liver diseases, yet the significant contribution of YY1 to drug-induced liver injury (DILI) appears to have been underestimated by researchers.

PURPOSE

To reveal the underlying role of YY1 in DILI.

METHOD

The compounds that interact with YY1 were queried in the Comparative Toxicogenomics Database (CTD), with the majority found to be hepatotoxic, which includes certain widely used drugs. Molecular docking and SPR characterized the robust binding of hepatotoxic compounds to YY1. The duty of YY1 in DILI was investigated in Diosbulbin B (DIOB), a recently identified hepatotoxic compound that tightly associates with YY1, and further validated on ANIT, LCA, APAP, and CDDP. Transcriptomic analysis disclosed the underlying mechanisms involved in DIOB-induced liver injury. RT-qPCR, immunohistochemistry, immunofluorescence, western blotting, and cellular transfection techniques were employed to validate the specific mechanism.

RESULTS

Among the 94 compounds affecting YY1 expression in the CTD, 59 compounds exhibited hepatotoxicity, showing close interactions with YY1 and almost consistent binding sites by molecular docking. The SPR validated the tough binding of several hepatotoxic compounds to YY1, including five FDA-approved hepatotoxic drugs. Mechanistically, the involvement of YY1 in DILI was uncovered through the cholestasis lens, mice hepatic YY1 was up-regulated by hepatotoxic DIOB and transcriptionally inhibited FXR and its downstream BSEP and MRP2 expression, initiating early in cholestatic liver injury and persisting to drive the progression of cholestasis. ANIT and LCA-induced model of cholestasis provided evidence for the hypothesis that YY1 frequently mediates drug induced cholestasis (DIC). APAP and CDDP indicated that YY1 may also be involved in hepatocellular and mixed type DILI.

CONCLUSION

YY1 widely mediated the development of DIC and also might be engaged in other types of DILI. YY1 presented a common target for hepatotoxic medications and the targeting of liver YY1 for drug development may offer a novel approach for managing DILI.

Single-cell transcriptome sequencing-based analysis: probing the mechanisms of glycoprotein NMB regulation of epithelial cells involved in silicosis

Chronic exposure to silica can lead to silicosis, one of the most serious occupational lung diseases worldwide, for which there is a lack of effective therapeutic drugs and tools. Epithelial mesenchymal transition plays an important role in several diseases; however, data on the specific mechanisms in silicosis models are scarce. We elucidated the pathogenesis of pulmonary fibrosis via single-cell transcriptome sequencing and constructed an experimental silicosis mouse model to explore the specific molecular mechanisms affecting epithelial mesenchymal transition at the single-cell level. Notably, as silicosis progressed, glycoprotein non-metastatic melanoma protein B (GPNMB) exerted a sustained amplification effect on alveolar type II epithelial cells, inducing epithelial-to-mesenchymal transition by accelerating cell proliferation and migration and increasing mesenchymal markers, ultimately leading to persistent pulmonary pathological changes. GPNMB participates in the epithelial-mesenchymal transition in distant lung epithelial cells by releasing extracellular vesicles to accelerate silicosis. These vesicles are involved in abnormal changes in the composition of the extracellular matrix and collagen structure. Our results suggest that GPNMB is a potential target for fibrosis prevention.

Novel insight into the underlying dysregulation mechanisms of immune cell-to-cell communication by analyzing multitissue single-cell atlas of two COVID-19 patients

How does SARS-CoV-2 cause lung microenvironment disturbance and inflammatory storm is still obscure. We here performed the single-cell transcriptome sequencing from lung, blood, and bone marrow of two dead COVID-19 patients and detected the cellular communication among them. Our results demonstrated that SARS-CoV-2 infection increase the frequency of cellular communication between alveolar type I cells (AT1) or alveolar type II cells (AT2) and myeloid cells triggering immune activation and inflammation microenvironment and then induce the disorder of fibroblasts, club, and ciliated cells, which may cause increased pulmonary fibrosis and mucus accumulation. Further study showed that the increase of T cells in the lungs may be mainly recruited by myeloid cells through ligands/receptors (e.g., ANXA1/FPR1, C5AR1/RPS19, and CCL5/CCR1). Interestingly, we also found that certain ligands/receptors (e.g., ANXA1/FPR1, CD74/COPA, CXCLs/CXCRs, ALOX5/ALOX5AP, CCL5/CCR1) are significantly activated and shared among lungs, blood and bone marrow of COVID-19 patients, implying that the dysregulation of ligands/receptors may lead to immune cell's activation, migration, and the inflammatory storm in different tissues of COVID-19 patients. Collectively, our study revealed a possible mechanism by which the disorder of cell communication caused by SARS-CoV-2 infection results in the lung inflammatory microenvironment and systemic immune responses across tissues in COVID-19 patients.

Ferulic acid prevents Diosbulbin B-induced liver injury by inhibiting covalent modifications on proteins

Diosbulbin B (DIOB) has been reported to cause serious liver injury. However, in traditional medicine, DIOB-containing herbs are highly safe in combination with ferulic acid (FA)-containing herbs, suggesting potential neutralizing effect of FA on the toxicity of DIOB. DIOB can be metabolized to generate reactive metabolites (RMs), which can covalently bind to proteins and lead to hepatoxicity. In the present study, the quantitative method was firstly established for investigating the correlation between DIOB RM-protein adducts (DRPAs) and hepatotoxicity. Then, we estimated the detoxication effect of FA in combination with DIOB and revealed the underlying mechanism. Our data indicated that the content of DRPAs positively correlate with the severity of hepatotoxicity. Meanwhile, FA is able to reduce the metabolic rate of DIOB in vitro. Moreover, FA suppressed the production of DRPAs and decreased the serum alanine/aspartate aminotransferase (ALT/AST) levels elevated by DIOB in vivo. Thus, FA can ameliorate DIOB-induced liver injury through reducing the production of DRPAs.

Angelica sinensis polysaccharide (ASP) attenuates diosbulbin-B (DB)-induced hepatotoxicity through activating the MEK/ERK pathway

Diosbulbin-B (DB) is a promising therapeutic drug for cancer treatment; however, DB-induced hepatotoxicity seriously limits its clinical utilization. Based on this, the present study investigated whether the Angelica sinensis extract, angelica sinensis polysaccharide (ASP), was effective to attenuate DB-induced cytotoxicity in hepatocytes. The primary hepatocytes were isolated from rats and cultured in vitro, which were subsequently treated with high-dose DB (100 μM) and ASP (12 μg/ml) to establish the DB-induced hepatotoxicity models. MTT assay and flow cytometry (FCM) were performed to evaluate cell viability, and the results showed that high-dose DB-induced cell apoptosis and inhibition of proliferation were reversed by co-treating cells with ASP, which were supported by our Western Blot assay data that ASP upregulated Cyclin D1 and CDK2 to abrogate high-dose DB-induced cell cycle arrest. In addition, ASP exerted its regulating effects on cell autophagy, and we found that ASP increased LC3B-II/I ratio and Atg5, but decreased p62 to activate the autophagy flux. Of note, the MEK/ERK pathway could be activated by ASP in the DB-treated hepatocytes, and the protective effects of ASP on high-dose DB-induced hepatocyte death were abolished by co-treating cells with the autophagy inhibitor (3-methyladenine, 3-MA) and MEK/ERK selective inhibitor (SCH772984). Moreover, blockage of the MEK/ERK pathway suppressed cell autophagy in the hepatocytes co-treated with ASP and high-dose DB. Taken together, this in vitro study illustrated that ASP activated the MEK/ERK pathway mediated autophagy to suppress high-dose DB-induced hepatotoxicity.

Biotransformation patterns of dictamnine in vitro/in vivo and its relative molecular mechanism of dictamnine-induced acute liver injury in mice

Dictamnine (DIC), a typical furan-quinoline alkaloid, has a wide range of pharmacological and toxicological effects, such as anti-bacterial, antifungal, anti-cancer, and hepatoxicity. But the molecular mechanism of DIC-induced hepatoxicity in mice remains unclear. This study aimed to clarify the biotransformation patterns of DIC in vitro/in vivo and the relative molecular mechanism of DIC-induced hepatoxicity in mice. All metabolites of DIC were identified by comparing the blank and drug-containing urine, feces, plasma, and liver samples. The structure of epoxide intermediate derived from DIC was confirmed by trapping assay. Oxidative stress injury and inflammation have been confirmed to be involved in the toxicological process of DIC-induced hepatoxicity in mice by detecting the relative biochemical indexes. The results will help to develop a deeper understanding about the biotransformation patterns of DIC, structure of the epoxide intermediate, and the molecular mechanism of DIC-induced hepatoxicity in mice.

Parthenolide plays a protective role in the liver of mice with metabolic dysfunction‑associated fatty liver disease through the activation of the HIPPO pathway

Metabolic dysfunction‑associated fatty liver disease (MAFLD) is a serious threat to human health. Parthenolide (PAR) displays several important pharmacological activities, including the promotion of liver function recovery during hepatitis. The aim of the present study was to assess the effect of PAR on MAFLD in a mouse model. Body weight, liver to body weight ratios, histological score, alanine transaminase, aspartate transaminase, total cholesterol and triglyceride levels were determined to evaluate liver injury. Liver hydroxyproline concentrations were also assessed. The expression levels of lipid metabolism‑related genes (sterol regulatory element binding protein‑1c, fatty acid synthase, acetyl CoA carboxylase 1, stearoyl CoA desaturase 1 and carbohydrate response element‑binding protein, peroxisome proliferator‑activated receptor α, carnitine palmitoyl transferase 1α and acyl‑CoA dehydrogenase short chain), liver fibrosis‑associated genes (α‑smooth muscle actin, tissue inhibitor of metalloproteinase 1 and TGF‑β1), pro‑inflammatory cytokines (TNF‑α, IL‑1β and IL‑6) and oxidative stress‑associated enzymes (malondialdehyde, superoxide dismutase and glutathione peroxidase) were measured in mice with MAFLD. The expression levels of genes associated with the HIPPO pathway were also measured. In vivo experiments using a specific inhibitor of HIPPO signalling were performed to verify the role of this pathway in the effects of PAR. PAR exerted beneficial effects on liver injury, lipid metabolism, fibrosis, inflammation and oxidative stress in mice with MAFLD, which was mediated by activation of the HIPPO pathway.

The miR-139-5p/peripheral myelin protein 22 axis modulates TGF-β-induced hepatic stellate cell activation and CCl4-induced hepatic fibrosis in mice

Hepatic stellate cells (HSCs) are the major source of extracellular matrix (ECM)-producing myofibroblasts. When activated by multiple injuries, HSCs become proliferative, contractile, inflammatory and chemotactic and are characterized by enhanced ECM production, which plays a central role in hepatic fibrosis initiation and progression. In the present study, through bioinformatics analysis, we identified the abnormal upregulation of Peripheral Myelin Protein 22 (PMP22) in fibrotic murine liver. In CCl₄-induced hepatic fibrosis model in mice and TGF-β-activated hHSCs, PMP22 was observed remarkably upregulated. In TGF-β-stimulated hHSCs, PMP22 silencing hindered, whereas PMP22 overexpression aggravated TGF-β-induced hHSC activation. In CCl₄-induced hepatic fibrosis model in mice, PMP22 silencing improved CCl₄-caused liver damage and fibrotic changes. Through online tools prediction and experimental validation, miR-139-5p was found to bind to the 3'UTR of PMP22 and negatively regulate the expression of PMP22. In contrast to PMP22 silencing, miR-139-5p inhibition enhanced TGF-β-induced hHSC activation; the effects of miR-139-5p inhibition on TGF-β-induced hHSC activation were partially reversed by PMP22 silencing. In conclusion, we identify the abnormal upregulation of PMP22 in TGF-β-activated HSCs and CCl₄-induced hepatic fibrosis model in mice, as well as the pro-fibrotic role of PMP22 through aggravating TGF-β-induced HSCs activation. miR-139-5p targets the 3'UTR of PMP22 and inhibits PMP22 expression; miR-139-5p hinders TGF-β-induced HSCs activation through targeting PMP22.

Low-dose Diosbulbin-B (DB) activates tumor-intrinsic PD-L1/NLRP3 signaling pathway mediated pyroptotic cell death to increase cisplatin-sensitivity in gastric cancer (GC)

Background

Emerging evidences suggests that Diosbulbin-B (DB) is effective to improve cisplatin (DDP)-sensitivity in gastric cancer (GC), but its molecular mechanisms were not fully delineated, and this study managed to investigate this issue.

Methods

Genes expressions were determined by Real-Time qPCR and Western Blot at transcriptional and translational levels. Cell proliferation and viability were evaluated by cell counting kit-8 (CCK-8) and trypan blue staining assay. Annexin V-FITC/PI double staining assay was used to examine cell apoptosis. The Spheroid formation assay was used to evaluated cell stemness. The xenograft tumor-bearing mice models were established, and the tumors were monitored and the immunohistochemistry (IHC) was employed to examine the expressions and localization of Ki67 protein in mice tumor tissues.

Results

Low-dose DB (12.5 μM) downregulated PD-L1 to activate NLRP3-mediated pyroptosis, and inhibited cancer stem cells (CSCs) properties, to sensitize cisplatin-resistant GC (CR-GC) cells to cisplatin. Mechanistically, the CR-GC cells were obtained, and either low-dose DB or cisplatin alone had little effects on cell viability in CR-GC cells, while low-dose DB significantly induced apoptotic cell death in cisplatin treated CR-GC cells. In addition, low-dose DB triggered cell pyroptosis in CR-GC cells co-treated with cisplatin, which were abrogated by silencing NLRP3. Next, CSCs tended to be enriched in CR-GC cells, instead of their parental cisplatin-sensitive GC (CS-GC) cells, and low-dose DB inhibited spheroid formation and stemness biomarkers (SOX2, OCT4 and Nanog) expressions to eliminate CSCs in CR-GC cells, which were reversed by upregulating programmed death ligand-1 (PD-L1). Furthermore, we proved that PD-L1 negatively regulated NLRP3 in CR-GC cells, and low-dose DB activated NLRP3-mediated pyroptotic cell death in cisplatin treated CR-GC cells by downregulating PD-L1. Also, low-dose DB aggravated the inhibiting effects of cisplatin on tumorigenesis of CR-GC cells in vivo.

Conclusions

Collectively, low-dose DB regulated intrinsic PD-L1/NLRP3 pathway to improve cisplatin-sensitivity in CR-GC cells, and this study provided alternative therapy treatments for GC.