A systemic combined nontargeted and targeted LC-MS based metabolomic strategy of plasma and liver on pathology exploration of alpha-naphthylisothiocyanate induced cholestatic liver injury in mice

Forsythiaside-A improved bile-duct-ligation-induced liver fibrosis in mice: The involvement of alleviating mitochondrial damage and ferroptosis in hepatocytes via activating Nrf2

Liver fibrosis is a key and reversible stage in the progression of many chronic liver diseases to cirrhosis or hepatocellular carcinoma. Forsythiaside-A (FTA), a main compound isolated from Forsythiae Fructus, has an excellent liver protective activity. This study aims to investigate the efficacy of FTA in improving cholestatic liver fibrosis. Bile-duct-ligation (BDL) was conducted to induce liver fibrosis in mice. Hepatic collagen deposition was evaluated by Masson and Sirus red staining. The bile acid spectrum in the liver and serum was analyzed by mass spectrometry. Liver oxidative stress injury and mitochondria damage were observed by using Mito-Tracker Red fluorescence staining, transmission electron microscopy, etc. The level of ferrous iron (Fe2+) and the expression of ferroptosis-associated molecules were detected. The binding between FTA and its target protein was confirmed by Co-immunoprecipitation (Co-IP), cellular thermal shift assay (CETSA), drug affinity responsive target stability (DARTS) and surface plasmon resonance (SPR). Our results demonstrated that FTA alleviated BDL-induced liver fibrosis in mice. FTA did not decrease the elevated amount of bile acids in BDL-treated mice, but reduced the bile acid-induced mitochondrial damage, oxidative stress and ferroptosis in hepatocytes, and also induced nuclear factor erythroid 2-related factor-2 (Nrf2) activation. In Nrf2 knock-out mice, the FTA-provided protection against BDL-induced liver fibrosis was disappeared, and FTA's inhibition on mitochondrial damage, oxidative stress and ferroptosis were lowered. Further results displayed that FTA could directly bind to Kelch-like ECH-associated protein-1 (Keap1), thereby activating Nrf2. Moreover, the BDL-induced liver fibrosis was markedly weakened in liver-specific Keap1 knockout mice. Hence, this study suggests that FTA alleviated the BDL-induced liver fibrosis through attenuating mitochondrial damage and ferroptosis in hepatocytes by activating Nrf2 via directly binding to Keap1.

Identification of multiple plasma lipids as diagnostic biomarkers of hypercholesterolemia and the underlying mechanisms based on pseudo-targeted lipidomics

RATIONALE

Hypercholesterolemia is an important risk factor for cardiovascular diseases and death. This study performed pseudo-targeted lipidomics to identify differentially expressed plasma lipids in hypercholesterolemia, to provide a scientific basis for the diagnosis and pathogenesis of hypercholesterolemia.

METHODS

Pseudo-targeted lipidomic analyses of plasma lipids from 20 patients with hypercholesterolemia and 20 normal control subjects were performed using liquid chromatography-mass spectrometry. Differentially expressed lipids were identified by principal component analysis and orthogonal partial least squares discriminant analysis. Receiver operating characteristic curves were used to identify differentially expressed lipids with high diagnostic value. The Kyoto Encyclopedia of Genes and Genomes pathway database was used to identify enriched metabolic pathways.

RESULTS

We identified 13 differentially expressed lipids in hypercholesterolemia using variable importance of projection > 1 and p < 0.05 as threshold parameters. The levels of eight sphingomyelins and cholesterol sulfate were higher and those of three triacylglycerols and lysophosphatidylcholine were reduced in hypercholesterolemia. Seven differentially expressed plasma lipids showed high diagnostic value for hypercholesterolemia. Functional enrichment analyses showed that pathways related to necroptosis, sphingolipid signaling, sphingolipid metabolism, and steroid hormone biosynthesis were enriched.

CONCLUSIONS

This pseudo-targeted lipidomics study demonstrated that multiple sphingomyelins and cholesterol sulfate were differentially expressed in the plasma of patients with hypercholesterolemia. We also identified seven plasma lipids, including six sphingomyelins and cholesterol sulfate, with high diagnostic value.

Detrimental Role of CXCR3 in α-Naphthylisothiocyanate- and Triptolide-Induced Cholestatic Liver Injury

The chemokine receptor CXCR3 is functionally pleiotropic, not only recruiting immune cells to the inflamed liver but also mediating the pathological process of cholestatic liver injury (CLI). However, the mechanism of its involvement in the CLI remains unclear. Both alpha-naphthylisothiocyanate (ANIT) and triptolide are hepatotoxicants that induce CLI by bile acid (BA) dysregulation, inflammation, and endoplasmic reticulum (ER)/oxidative stress. Through molecular docking, CXCR3 is a potential target of ANIT and triptolide. Therefore, this study aimed to investigate the role of CXCR3 in ANIT- and triptolide-induced CLI and to explore the underlying mechanisms. Wild-type mice and CXCR3-deficient mice were administered with ANIT or triptolide to compare CLI, BA profile, hepatic recruitment of IFN-γ/IL-4/IL-17+CD4+T cells, IFN-γ/IL-4/IL-17+iNKT cells and IFN-γ/IL-4+NK cells, and the expression of ER/oxidative stress pathway. The results showed that CXCR3 deficiency ameliorated ANIT- and triptolide-induced CLI. CXCR3 deficiency alleviated ANIT-induced dysregulated BA metabolism, which decreased the recruitment of IFN-γ+NK cells and IL-4+NK cells to the liver and inhibited ER stress. After triptolide administration, CXCR3 deficiency ameliorated dysregulation of BA metabolism, which reduced the migration of IL-4+iNKT cells and IL-17+iNKT cells and reduced oxidative stress through inhibition of Egr1 expression and AKT phosphorylation. Our findings suggest a detrimental role of CXCR3 in ANIT- and triptolide-induced CLI, providing a promising therapeutic target and introducing novel mechanisms for understanding cholestatic liver diseases.

A new insight into mechanism of colchicine poisoning based on untargeted metabolomics

BACKGROUND

Colchicine (COL) is a well-known plant-derived mitogenic toxin that has been widely applied for the treatment of immune system diseases and various cancers. However, its clinical use is severely limited by frequent occurrence of poisoning accidents, and the mechanism of COL poisoning is not clear yet.

PURPOSE

The present study aimed to unveil how COL works as a toxin based on untargeted metabolomics analysis of animal models and clinical human case.

METHODS

KM mice orally administered COL were used to establish poisoning models, and plasma samples were collected for untargeted metabolomics analysis. The data mining was performed to screen dose-dependent differences and disturbed metabolic pathways. The blood samples collected from clinical COL poisoning human case at various time points during treatment period were further analyzed to investigate the temporal changes in the metabolic disposition of COL in vivo and also verify the findings from mice. Finally, the expression of key pathways was evaluated by ELISA and Western blotting analysis.

RESULTS

Histological examination demonstrated systemic toxicity of COL poisoning in mice. Metabolite profiling analysis of plasma samples from model mice and clinical case both revealed that COL poisoning could significantly disturb in vivo metabolism of amino acid and lipid metabolism by the FXR/AMPK signal pathway. Quantitative monitoring of the metabolic process of COL further demonstrated that it could be greatly ameliorated with the rapid metabolic transformation of COL in vivo, which thus may be an effective detoxification pathway for COL poisoning.

CONCLUSION

The findings of the present study provided new insight into the molecular mechanism of COL poisoning, thus helpful for guiding reasonable application of this phytotoxin.

Paeoniflorin alleviates 17α-ethinylestradiol-induced cholestasis via the farnesoid X receptor-mediated bile acid homeostasis signaling pathway in rats

Cholestasis, characterized by disturbance of bile formation, is a common pathological condition that can induce several serious liver diseases. As a kind of trigger, estrogen-induced cholestasis belongs to drug-induced cholestasis. Paeoniflorin is the most abundant bioactive constituent in Paeonia lactiflora Pall., Paeonia suffruticosa Andr., or Paeonia veitchii Lynch, a widely used herbal medicine for treating hepatic disease over centuries in China. However, the pharmacologic effect and mechanism of paeoniflorin on estrogen-induced cholestasis remain unclear. In this experiment, the pharmacological effect of paeoniflorin on EE-induced cholestasis in rats was evaluated comprehensively for the first time. Ultra-high-performance liquid chromatography coupled with Q-Exactive orbitrap mass spectrometer was used to monitor the variation of bile acid levels and composition. It was demonstrated that paeoniflorin alleviated 17α-ethinylestradiol (EE)-induced cholestasis dose-dependently, characterized by a decrease of serum biochemical indexes, recovery of bile flow, amelioration of hepatic and ileal histopathology, and reduction of oxidative stress. In addition, paeoniflorin intervention restored EE-disrupted bile acid homeostasis in enterohepatic circulation. Further mechanism studies using western blot, quantitative Real-Time PCR, and immunohistochemical showed that paeoniflorin could upregulate hepatic efflux transporters expression but downregulate hepatic uptake transporter expression. Meanwhile, paeoniflorin reduced bile acids synthesis by repressing cholesterol 7α-hydroxylase in hepatocytes. Paeoniflorin affected the above transporters and enzyme via activation of a nuclear receptor, farnesoid X receptor (FXR), which was recognized as a vital regulator for maintaining bile acid homeostasis. In conclusion, paeoniflorin alleviated EE-induced cholestasis and maintained bile acid homeostasis via FXR-mediated regulation of bile acids transporters and synthesis enzyme. The findings indicated that paeoniflorin might exert a potential therapeutic medicine for estrogen-induced cholestasis.

Paeoniae Radix Rubra can enhance fatty acid β-oxidation and alleviate gut microbiota disorder in α-naphthyl isothiocyanate induced cholestatic model rats

Cholestasis is the most destructive pathological manifestation of liver disease and available treatments are very limited. Paeoniae Radix Rubra (PRR) is an important traditional Chinese drug used to treat cholestasis. This study combined targeted metabonomics, PCR array analysis, and 16S rRNA sequencing analysis to further clarify the mechanisms of PRR in the treatment of cholestasis. PRR conspicuously reversed the elevation of fatty acids (FFA 14:0 and other 14 fatty acids) and the decrease of organic acids (pyruvic acid and citric acid) in a cholestatic model induced by α-naphthyl isothiocyanate (ANIT). Eight elevated amino acids (L-proline, etc.) and five elevated secondary bile acids (taurohyodeoxycholic acid, etc.) in model rats were also reduced by PRR. Pathway analysis revealed that PRR significantly alleviated eight pathways (β-alanine metabolism). Furthermore, we found that PRR significantly reversed the decrease of Cpt1a, Hadha, Ppara, and Slc25a20 (four genes relevant to fatty acid β-oxidation) mRNAs caused by ANIT, and PRR conspicuously decreased nine acylcarnitines (the forms of fatty acids into mitochondria for β-oxidation) that increased in model rats. These results indicate that PRR could enhance fatty acid β-oxidation, which may be the way for PRR to reduce the levels of 15 fatty acids in the serum of model rats. 16S rRNA sequencing analysis revealed that PRR alleviated gut microbiota disorders in model rats, including upregulating four genera (Coprococcus, Lactobacillus, etc.) and downregulating four genera (Bacteroides, Escherichia, etc.). As the relative abundance of these eight genera was significantly correlated with the levels of the five secondary bile acids (deoxycholic acid, taurolithocholic acid, etc.) reduced by PRR, and Bacteroides and Escherichia were reported to promote the production of secondary bile acid, we inferred that the downregulation of PRR on five secondary bile acids in model rats was inseparable from gut microbiota. Thus, the gut microbiota also might be a potential pharmacological target for the anticholestatic activity of PRR. In conclusion, we consider that the mechanisms of PRR in treating cholestasis include enhancing fatty acid β-oxidation and alleviating gut microbiota disorders.

Bias caused by incomplete metabolite extraction and matrix effect: Evaluation of critical factors for plasma sample preparation prior to metabolomics

Metabolomics is an omics strategy to study the metabolite alteration in the biological system. Unbiased observation of the metabolite level is essential for targeted metabolite quantification and untargeted metabolic profiling. State-of-the-art instruments and versatile tools have been developed for accurate observation of metabolic alterations in various studies. Several analytical pitfalls, such as sample overloading and signal-saturation-induced bias, have been revealed and addressed. In this study, we proposed incomplete-metabolite-extraction-caused bias is also an important issue that results in biased observation when performing metabolomics. In the demonstration example, numerous metabolites exhibited no significant difference between extracted plasma samples with different plasma contents, which is attributed to incomplete-metabolite-extraction-caused bias and matrix effect. Matrix effect is a well-known factor that result in biased observation, it can be reduced by sample dilution and compensated by using stable isotope labelled internal standards. The detection of metabolite signals in the following consecutive extractions provided further evidence of incomplete metabolite extraction. The completeness of metabolite extraction is crucial for unbiased observation of metabolic profile changes. To address this issue, we optimized the extraction time and methanol volume to reduce the incomplete-metabolite-extraction-caused bias and evaluated the metabolite signals in consecutive extractions. Methanol extraction performed with a plasma-to-methanol ratio of 1:14 resulted in metabolite responses of less than 18.1 % in the second extractions observed by metabolomic profiling. Finally, the optimized sample preparation procedure and untargeted profiling platform were applied to detect metabolite alterations associated with patients with cerebrovascular diseases and several features with significant difference were successfully identified. This study revealed and evaluated the bias caused by incomplete metabolite extraction and matrix effect in the commonly used methanol extraction method for human plasma sample preparation for metabolomics. We anticipate the proposed metabolite extraction evaluation method could benefit more clinical and biological metabolomics studies.

Swertiamarin, an active iridoid glycoside from Swertia pseudochinensis H. Hara, protects against alpha-naphthylisothiocyanate-induced cholestasis by activating the farnesoid X receptor and bile acid excretion pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Swertiamarin (SW), which belongs to iridoid glycosides, is one of the main components of Swertia plants in Gentianaceae family, including Swertia pseudochinensis H. Hara and Swertia mileensis T. N. Ho et W. L. Shi. There are mainly used in traditional Chinese medicine for the treatment of hepatic and biliary disease such as jaundice.

AIM OF THIS STUDY

This experiment aimed to explore the protective mechanism of SW on cholestasis induced by alpha-naphthylisothiocyanate in rats.

MATERIALS AND METHODS

Healthy rats were randomly divided into the control, model (ANIT, 50 mg/kg), ursodeoxycholic acid (UDCA, 80 mg/kg), and low-dose (SW, 80 mg/kg), medium-dose (SW, 100 mg/kg), and high-dose (SW, 150 mg/kg) groups. The hepatic protective effect of SW was preliminarily evaluated by measurement of serum biochemical indicators and liver morphological evaluation. Moreover, metabolomics and proteomics analysis were used to explore the protective mechanism of SW on cholestasis. The expression of related proteins was determined by Western blot and polymerase chain reaction, and the important proteins were verified by cell experiments in vitro.

RESULTS

SW (100 mg/kg) can reduce the serum levels of the model group. The hepatocyte of the medium-dose treatment group was arranged neatly without evident inflammation. SW can partially reverse the changes in cholestasis metabolites, such as taurocholic acid, SM (d18:1/16:0), all-trans-retinoic acid and other products of rats. The main metabolic pathways affected were primary bile acid synthesis, glycerophospholipid metabolism, sphingolipid metabolism and retinol metabolism. SW medium-dose treatment group showed effective reversal of 25 related proteins and it can remarkably reduce the contents of NTCP and CYP27A1 in rat liver and increase the protein expressions of CYP7A1, CYP8B1, bile salt export pump, multidrug resistance-associated protein and FXR.

CONCLUSIONS

SW can alleviate ANIT-induced cholestasis, which by activating the farnesoid X receptor and bile acid excretion pathway.

Metabolomic Profiling Reveals Protective Effects and Mechanisms of Sea Buckthorn Sterol against Carbon Tetrachloride-Induced Acute Liver Injury in Rats

The present study was designed to examine the efficacy and protection mechanisms of sea buckthorn sterol (SBS) against acute liver injury induced by carbon tetrachloride (CCl₄) in rats. Five-week-old male Sprague-Dawley (SD) rats were divided into six groups and fed with saline (Group BG), 50% CCl₄ (Group MG), or bifendate 200 mg/kg (Group DDB), or treated with low-dose (Group LD), medium-dose (Group MD), or high-dose (Group HD) SBS. This study, for the first time, observed the protection of SBS against CCl₄-induced liver injury in rats and its underlying mechanisms. Investigation of enzyme activities showed that SBS-fed rats exhibited a significant alleviation of inflammatory lesions, as evidenced by the decrease in cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2), and gamma-glutamyl transpeptidase (γ-GT). In addition, compared to the MG group, the increased indices (superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT), total antioxidant capacity (T-AOC), and total protein (TP)) of lipid peroxidation and decreased malondialdehyde (MDA) in liver tissues of SBS-treated groups showed the anti-lipid peroxidation effects of SBS. Using the wide range of targeted technologies and a combination of means (UPLC-MS/MS detection platform, self-built database, and multivariate statistical analysis), the addition of SBS was found to restore the expression of metabolic pathways (e.g., L-malic acid, N-acetyl-aspartic acid, N-acetyl-l-alanine, etc.) in rats, which means that the metabolic damage induced by CCl₄ was alleviated. Furthermore, transcriptomics was employed to analyze and compare gene expression levels of different groups. It showed that the expressions of genes (Cyp1a1, Noct, and TUBB6) related to liver injury were regulated by SBS. In conclusion, SBS exhibited protective effects against CCl₄-induced liver injury in rats. The liver protection mechanism of SBS is probably related to the regulation of metabolic disorders, anti-lipid peroxidation, and inhibition of the inflammatory response.

An integrated pathological research for precise diagnosis of schizophrenia combining LC-MS/1H NMR metabolomics and transcriptomics

BACKGROUND

Lack of clinically specific biomarkers has impeded the precise diagnosis of schizophrenia, meanwhile, limited comprehending of pathogenesis for schizophrenia has restricted the effective treatment.

METHOD

An integrated multi-omic approach, combining metabolomic platform (LC-MS and ¹H NMR) and transcriptomic platform, was established to differentiate healthy subjects from schizophrenia patients. Based on filtered metabolites and genes, characteristic spectrums were further built. Then, representative metabolites and genes were screened out through Boruta algorithm. Moreover, characteristic diagnostic formulas were established via LASSO regression analysis.

RESULT

As a result, 86 differential metabolites (in line with amino acid metabolism, etc.) and 189 differential expression genes (involving in amino acid metabolic process, etc.) were obtained as potential biomarkers for schizophrenia. The latent interaction between metabolites with genes, such as HMGCLL1 with energy metabolism, etc., was further studied through the analysis of pathway-based integration. Moreover, fine predictive ability was attributed to characteristic metabolomic/transcriptomic diagnostic spectrums/formulas.

CONCLUSION

The functional relationships of filtered metabolites and genes were studied, which could elaborate the pathological process of schizophrenia more systemically, supplying more precise information on mechanism description and diagnostic evidence of schizophrenia.

Integrated DIA proteomics and lipidomics analysis on non-small cell lung cancer patients with TCM syndromes

Background

Lung cancer remains the leading cause of mortality from malignant tumors, non-small cell lung cancer (NSCLC) accounts for the majority of lung cancer cases, and individualized diagnosis and treatment is an effective trend. The individual characteristics of different traditional Chinese medicine (TCM) syndromes of NSCLC patients may be revealed by highly specific molecular profiles.

Methods

In this study, 10 NSCLC patients with Qi deficiency and Yin deficiency (QDYD) syndrome and 10 patients with Qi deficiency of lung-spleen (QDLS) syndrome in TNM stage III-IV as well as 10 healthy volunteers were enrolled. Aiming at the varied syndromes of NSCLC patients with “Yin deficiency” as the main difference, a proteomics research based on data-independent acquisition (DIA) was developed. Of the dysregulated proteins in NSCLC patients, lipid metabolism was significantly enriched. Thereafter, nontargeted lipidomics research based on UPLC-Q-TOF/MS was performed in 16 patients, with 8 individuals randomly selected from each syndrome group. Furthermore, the considerably different characteristics between the syndromes and pathological mechanisms of NSCLC were screened by statistical and biological integrations of proteomics and lipidomics and the differential metabolic pathways of the two similar syndromes were further explored. Besides, lipids biomarkers were verified by a clinically used anticancer Chinese medicine, and the level of key differential proteins in the two syndromes was also validated using ELISA.

Results

The results showed that glycerophospholipid metabolism, sphingolipid metabolism, glycolipid metabolism, and primary bile acid biosynthesis were altered in NSCLC patients and that glycerophospholipid metabolism was significantly changed between the two syndromes in lipidomics analysis. Among the proteins and lipids, ALDOC and lysophosphatidylcholine (LPCs) were revealed to have a strong relationship by statistical and biological integration analysis, and could effectively distinguish QDLS and QDYD syndromes. Notably, the patients with different syndromes had the most typical metabolic patterns in glycerophospholipid metabolism and glycolysis, reflecting the differences in the syndromes dominated by “Yin deficiency”.

Conclusions

ALDOC and LPCs could be employed for the differentiation of NSCLC patients with QDLS and QDYD syndromes, and “Yin deficiency” might be associated with glycerophospholipid metabolism and glycolysis pathway. The results provided a theoretical basis for “Syndrome differentiation” in TCM diagnosis. Moreover, the developed integrated strategy could also provide a reference for individualized diagnosis and treatment of other diseases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13020-021-00535-x.

A stepwise integrated multi-system to screen quality markers of Chinese classic prescription Qingzao Jiufei decoction on the treatment of acute lung injury by combining 'network pharmacology-metabolomics-PK/PD modeling'

BACKGROUND

Previously, we have investigated the therapeutic mechanism of Qingzao Jiufei Decoction (QZJFD), a Chinese classic prescription, on acute lung injury (ALI), however, which remained to be further clarified together with the underlying efficacy related compounds for quality markers (Q-markers).

HYPOTHESIS/PURPOSE

To explore Q-markers of QZJFD on ALI by integrating a stepwise multi-system with 'network pharmacology-metabolomics- pharmacokinetic (PK)/ pharmacodynamic (PD) modeling'.

METHODS

First, based on in vitro and in vivo component analysis, a network pharmacology strategy was developed to identify active components and potential action mechanism of QZJFD on ALI. Next, studies of poly-pharmacology and non-targeted metabolomics were used to elaborate efficacy and verify network pharmacology results. Then, a comparative PK study on active components in network pharmacology was developed to profile their dynamic laws in vivo under ALI, suggesting Q-marker candidates. Next, quantified analytes with marked PK variations after modeling were fitted with characteristic endogenous metabolites along drug concentration-efficacy-time curve in a PK-PD modeling to verify and select primary effective compounds. Finally, Q-markers were further chosen based on representativeness among analytes through validity analysis of PK quantitation of primary effective compounds.

RESULTS

In virtue of 121 and 33 compounds identified in vitro and in vivo, respectively, 33 absorbed prototype compounds were selected to construct a ternary network of '20 components-47 targets-113 pathways' related to anti-ALI of QZJFD. Predicted mechanism (leukocytes infiltration, cytokines, endogenous metabolism) were successively verified by poly-pharmacology and metabolomics. Next, 18 measurable components were retained from 20 analytes by PK comparison under ALI. Then, 15 primary effective compounds from 18 PK markers were further selected by PK-PD analysis. Finally, 9 representative Q-markers from 15 primary effective compounds attributed to principal (chlorogenic acid), ministerial (methylophiopogonanone A, methylophiopogonanone B), adjuvant (sesamin, ursolic acid, amygdalin), conductant drugs (liquiritin apioside, liquiritigenin and isoliquiritin) in QZJFD, were recognized by substitutability and relevance of plasmatic concentration at various time points.

CONCLUSION

9 Q-markers for QZJFD on ALI were identified by a stepwise integration strategy, moreover, which was a powerful tool for screening Q-makers involved with the therapeutic action of traditional Chinese medicine (TCM) prescription and promoting the process of TCM modernization and scientification.

Hepatotoxicity of nutmeg: A pilot study based on metabolomics

Incidences of abuse and poisoning have been reported for nutmeg, a household spice made from grinding the seed of Myristica fragrans, owing to its hallucinogenic properties. However, there have been no reports on nutmeg hepatotoxicity in relation to dose and duration of exposure. To investigate the hepatotoxicity of different nutmeg exposure durations and doses, male mice were administered daily with normal saline, 1.0 g/kg nutmeg, or 4.0 g/kg nutmeg by intragastrical gavage for either 7 or 14 days (for a total of six treatment groups, n = 6). Body weight of each mouse was monitored daily. Histological analysis of liver tissues was performed using hematoxylin and eosin (H&E) staining to investigate the morphological changes in hepatocytes. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were determined using enzyme-linked immunosorbent assay (ELISA) to investigate liver function. Metabolomics and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed between treatment groups for identifying differential metabolites. Mice in the nutmeg exposure groups exhibited slow growth trends, hepatocyte damage, and significantly elevated serum AST and ALT levels associated with nutmeg dose and exposure duration. Metabolomics and KEGG enrichment pathway analyses also revealed differential levels of some metabolites related to liver function upon nutmeg exposure. Therefore, the present study reasonably speculates that nutmeg exposure may cause liver damage and affect liver function depending on the dose and duration.

Acute lung injury therapeutic mechanism exploration for Chinese classic prescription Qingzao Jiufei Decoction by UFLC-MS/MS quantification of bile acids, fatty acids and eicosanoids in rats

Acute lung injury (ALI) is a common and complex inflammatory disease, which has been reasonably associated with carboxyl-containing metabolites in our preliminary non-targeted metabolomic strategy. Qingzao Jiufei Decoction (QZJFD), a classic prescription, is widely used in the treatment of pulmonary inflammatory injuries. Successively, in this targeted project, to fill in the research gap and exposit the therapeutic mechanism of QZJFD on ALI, considering the structure similarity and bioactivity correlation, 21 bile acids, 11 fatty acids and 19 eicosanoids were profiled simultaneously in plasma, lung, bronchoalveolar lavage fluid, spleen and feces from rats utilizing a novel ultraperformance liquid chromatography-mass spectrometry approach. As a result, potential biomarkers and ALI characteristic metabolomic spectrums were obtained to distinguish different physical states using discriminative similarity threshold as 0.65 for clinical application. After treatment with QZJFD, obvious reversing ability for various biomarker levels was observed in different bio-samples, providing insights into the systemic intervention of QZJFD on ALI by regulating bile acid synthesis, fatty acid synthesis and eicosanoid metabolism. Conclusively, this investigation represented more information on the comprehensive therapeutic action of QZJFD on ALI involving with multi-targets and multi-pathways for clinical application and traditional Chinese medicine modernization.

Sphingosine 1-phosphate receptor-1 specific agonist SEW2871 ameliorates ANIT-induced dysregulation of bile acid homeostasis in mice plasma and liver

Dysregulated bile acid (BA) homeostasis is an extremely significant pathological phenomenon of intrahepatic cholestasis, and the accumulated BA could further trigger hepatocyte injury. Here, we showed that the expression of sphingosine-1-phosphate receptor 1 (S1PR1) was down-regulated by α-naphthylisothiocyanate (ANIT) in vivo and in vitro. The up-regulated S1PR1 induced by SEW2871 (a specific agonist of S1PR1) could improve ANIT-induced deficiency of hepatocyte tight junctions (TJs), cholestatic liver injury and the disrupted BA homeostasis in mice. BA metabolic profiles showed that SEW2871 not only reversed the disruption of plasma BA homeostasis, but also alleviated BA accumulation in the liver of ANIT-treated mice. Further quantitative analysis of 19 BAs showed that ANIT increased almost all BAs in mice plasma and liver, all of which were restored by SEW2871. Our data demonstrated that the top performing BAs were taurine conjugated bile acids (T-), especially taurocholic acid (TCA). Molecular mechanism studies indicated that BA transporters, synthetase, and BAs nuclear receptors (NRs) might be the important factors that maintained BA homeostasis by SEW2871 in ANIT-induced cholestasis. In conclusion, these results demonstrated that S1PR1 selective agonists might be the novel and potential effective agents for the treatment of intrahepatic cholestasis by recovering dysregulated BA homeostasis.

Baicalin Protects Against 17α-Ethinylestradiol-Induced Cholestasis via the Sirtuin 1/Hepatic Nuclear Receptor-1α/Farnesoid X Receptor Pathway

Estrogen-induced cholestasis (EIC) is characterized by impairment of bile flow and accumulated bile acids (BAs) in the liver, always along with the liver damage. Baicalin is a major flavonoid component of Scutellaria baicalensis, and has been used in the treatment of liver diseases for many years. However, the role of baicalin in EIC remains to be elucidated. In this study, we demonstrated that baicalin showed obvious hepatoprotective effects in EIC rats by reducing serum biomarkers and increasing the bile flow rate, as well as by alleviating liver histology and restoring the abnormal composition of hepatic BAs. In addition, baicalin protected against estrogen-induced liver injury by up-regulation of the expression of hepatic efflux transporters and down-regulation of hepatic uptake transporters. Furthermore, baicalin increased the expression of hepatic BA synthase (CYP27A1) and metabolic enzymes (Bal, Baat, Sult2a1) in EIC rats. We showed that baicalin significantly inhibited hepatic inflammatory responses in EIC rats through reducing elevated levels of TNF-α, IL-1β, IL-6, and NF-κB. Finally, we confirmed that baicalin maintains hepatic BA homeostasis and alleviates inflammation through sirtuin 1 (Sirt1)/hepatic nuclear receptor-1α (HNF-1α)/farnesoid X receptor (FXR) signaling pathway. Thus, baicalin protects against estrogen-induced cholestatic liver injury, and the underlying mechanism involved is related to activation of the Sirt1/HNF-1α/FXR signaling pathway.

Metabolomic and Lipidomic Biomarkers for Premalignant Liver Disease Diagnosis and Therapy

In recent years, there has been a plethora of attempts to discover biomarkers that are more reliable than α-fetoprotein for the early prediction and prognosis of hepatocellular carcinoma (HCC). Efforts have involved such fields as genomics, transcriptomics, epigenetics, microRNA, exosomes, proteomics, glycoproteomics, and metabolomics. HCC arises against a background of inflammation, steatosis, and cirrhosis, due mainly to hepatic insults caused by alcohol abuse, hepatitis B and C virus infection, adiposity, and diabetes. Metabolomics offers an opportunity, without recourse to liver biopsy, to discover biomarkers for premalignant liver disease, thereby alerting the potential of impending HCC. We have reviewed metabolomic studies in alcoholic liver disease (ALD), cholestasis, fibrosis, cirrhosis, nonalcoholic fatty liver (NAFL), and nonalcoholic steatohepatitis (NASH). Specificity was our major criterion in proposing clinical evaluation of indole-3-lactic acid, phenyllactic acid, N-lauroylglycine, decatrienoate, N-acetyltaurine for ALD, urinary sulfated bile acids for cholestasis, cervonoyl ethanolamide for fibrosis, 16α-hydroxyestrone for cirrhosis, and the pattern of acyl carnitines for NAFL and NASH. These examples derive from a large body of published metabolomic observations in various liver diseases in adults, adolescents, and children, together with animal models. Many other options have been tabulated. Metabolomic biomarkers for premalignant liver disease may help reduce the incidence of HCC.

Metabolomic profile perturbations of serum, lung, bronchoalveolar lavage fluid, spleen and feces in LPS-induced acute lung injury rats based on HPLC-ESI-QTOF-MS

Acute lung injury (ALI) is a clinically common and serious disease, underscoring the urgent need for clarification of its pathogenesis. According to traditional Chinese medicine (TCM) theories on the "lung-spleen-intestine axis" and its correlation with ALI, a high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (HPLC-QTOF-MS) metabolomic platform was applied to identify biomarkers from five bio-samples of control and model rats challenged with intratracheally administered lipopolysaccharide (LPS) based on multivariate mathematical statistical analysis. As a result, 19, 24, 24, 15 and 29 altered metabolites were identified in serum, lung, bronchoalveolar lavage fluid (BALF), spleen and feces samples, respectively. Metabolic pathway analysis showed that linoleic acid, sphingolipid, glycerophospholipid and bile acid metabolism pathways were mainly altered by ALI. Additionally, ROC curves were applied to assess the specificity and sensitivity of the biomarkers. ALI characteristic metabolomic spectra were then established to differentiate the control from the model group with a similarity discriminative threshold of 0.7. Additionally, to compare the metabolomic profiles of the five bio-samples and establish metabolic similarities and differences among them, correlation analysis was conducted in order to delineate an objective law of endogenous linkage along the lung-spleen-intestine axis. Therefore, this study provides insights into the mechanisms involved in ALI from a metabolomics perspective, which can be applied in characterization of the mechanism and early disease detection. Graphical abstract.