[Widely targeted metabolomics reveals differential metabolites between root tuber and leaf of Fallopia multiflora].

This study aims to reveal the differences in the species and relative content of metabolites in the leaf and root tuber of Fallopia multiflora and improve the comprehensive utilization rate of F. multiflora resources. The metabolites in the root tubers and leaves of F. multiflora were detected by widely targeted metabolomics based on ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS). The principal component analysis, hierarchical cluster analysis, and orthogonal partial least squares-discriminant analysis were carried out to screen the differential metabolites between the leaf and root tuber of F. multiflora. The result showed that a total of 1 942 metabolites in 15 categories were detected in the leaf and root tuber of F. multiflora, including 1 861 metabolites in the root tuber, 1 901 metabolites in the leaf, and 1 820 metabolites in both. The metabolites were mainly phenolic acids, flavonoids, amino acids and derivatives, and alkaloids. A total of 1 200 differential metabolites were screened out, accounting for 65.9% of the total metabolites. Among these differential metabolites, 813 and 387 showed higher content in the leaf and root tuber, respectively. Flavonoids were the metabolites with the largest number and the most significant differences between the leaf and root tuber, and stilbenes and anthraquinones as the main active compounds mainly existed in the root tuber. The KEGG enrichment results suggested that the differential metabolites were mainly enriched in flavonoid and flavonol biosynthesis pathways and linoleic acid metabolism pathway. This study discovered abundant metabolites in F. multiflora. The metabolites were similar but had great differences in the content between the leaf and root tuber. The research results provide theoretical guidance for the development and utilization of F. multiflora resources.

HLA-B*35:01-mediated activation of emodin-specific T cells contributes to Polygonum multiflorum thunb. -induced liver injury in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: HLA-B*35:01 has been identified as a risk allele for Polygonum multiflorum Thunb.-induced liver injury (PMLI). However, the immune mechanism underlying HLA-B*35:01-mediated PMLI remains unknown. AIM OF THE STUDY: To characterize the immune mechanism of HLA-B*35:01-mediated PMLI. MATERIALS AND METHODS: Components of P. multiflorum (PM) bound to the HLA-B*35:01 molecule was screened by immunoaffinity chromatography. Both wild-type mice and HLA-B*35:01 transgenic (TG) mice were treated with emodin. The levels of transaminases, histological changes and T-cell response were assessed. Splenocytes from emodin-treated mice were isolated and cultured in vitro. Phenotypes and functions of T cells were characterized upon drug restimulation using flow cytometry or ELISA. Emodin-pulsed antigen-presenting cells (APCs) or glutaraldehyde-fixed APCs were co-cultured with splenocytes from emodin-treated transgenic mice to detect their effect on T-cell activation. RESULTS: Emodin, the main component of PM, could non-covalently bind to the HLA-B*35:01-peptide complexes. TG mice were more sensitive to emodin-induced immune hepatic injury, as manifested by elevated aminotransferase levels, infiltration of inflammatory cells, increased percentage of CD8+T cells and release of effector molecules in the liver. However, these effects were not observed in wild-type mice. An increase in percentage of T cells and the levels of interferon-γ, granzyme B, and perforin was detected in emodin-restimulated splenocytes from TG mice. Anti-HLA-I antibodies inhibited the secretion of these effector molecules induced by emodin. Mechanistically, emodin-pulsed APCs failed to stimulate T cells, while fixed APCs in the presence of emodin could elicit the secretion of T cell effector molecules. CONCLUSION: The HLA-B*35:01-mediated CD8+ T cell reaction to emodin through the P-I mechanism may contribute to P. multiflorum-induced liver injury.

Synergic effects and possible mechanism of emodin and stilbene glycosides on colorectal cancer.

BACKGROUND: Polygonum multiflorum (PM) is a core herb that enhances immunity. It can also detoxify, reduce swelling, and intercept malaria. Its main components, emodin (EMD) and 2,3,5,4'-Tetrahydroxy stilbene-2-O-ß-D-glucoside (stilbene glycoside, TSG), have good anti-cancer potential. PURPOSE: The study aims to investigate synergic effects of EMD and TSG on CRC and its possible mechanism. METHODS: Network pharmacology and bioinformatics were used to identify targets. HPLC was used to analyze the effective ingredients in PM and to determine the content of the main ingredients. HT-29 cells were used for in vitro experiments. Cell Counting Kit-8 (CCK8) and scratch test were used to detect the effects of various chemical components of PM on the proliferation and migration of HT-29 cells, and Western Bolt (WB) test was used to evaluate the effects of EMD and TSG on P53 pathway. In vivo experiments, the effects of EMD and TSG were evaluated by measuring tumor weight and tumor volume in CRC mice model and histological analysis were carried out with HE staining. The expressions of HSP90, P53, COX2, and ROS were detected by quantitative reverse transcription polymerase chain reaction (PCR), and IL-1ß, IL-4, IL-6, IL-10, TGF-ß and IFN-γ were detected by enzyme linked immunosorbent assay (ELISA). WB and Immunohistochemistry (IHC) were used to detect the expression of P53 related proteins. RESULTS: Network pharmacology showed PM closely related to colorectal cancer pathway and the core targets included STAT3 and P53; bioinformatics indicated P53 played an important role in the development and prognosis of CRC; chemical analysis showed identified and quantified gallic acid (GA), cis-TSG, trans-TSG, Emodin glucoside(EMDG), physcion glucoside (PHYG), EMD in PM; EMD induced apoptosis and TSG inhibited migration of HT-29 cells; EMD and TSG could coordinately shrink tumor size of CRC mice, elevate expressions of F4/80, decrease the content of IL-6 and TGF-ß, promote tumor oxidized and reduce expression of P53 and STAT3 in the tumor. CONCLUSIONS: In vitro experiments showed that TSG inhibited cancer cell migration and EMD induced apoptosis. EMD and TSG had synergic effects on CRC, whose possible mechanism might be to regulate the expression of cytokines and inhibit P53 pathway.

Research progress on hepatotoxicity mechanism of polygonum multiflorum and its main components.

As a traditional tonic Chinese medicine, Polygonum multiflorum is widely used in clinical practice. However, with the deepening of modern pharmacological research, its drug toxicity, especially hepatotoxicity, has become increasingly prominent. Based on a large number of clinical and experimental evidence, it has been confirmed that Polygonum multiflorum and its main active ingredients such as anthraquinones and diphenylethylene glucoside can cause different degrees of hepatotoxicity. Further studies have shown that the toxicological mechanisms involved in the hepatotoxicity of different extracts and components of Polygonum multiflorum may include oxidative phosphorylation, bile acid excretion, different metabolic pathways, genetic and metabolic factors, immune homeostasis, etc. By sorting out and summarizing the literature related to hepatotoxicity of Polygonum multiflorum in recent years, this paper discussed the hepatotoxicity mechanism of Polygonum multiflorum and its main components and some contradictions in related reports.

Evaluating the anticancer potential of Polygonum multiflorum root-derived stilbenes against H2452 malignant pleural mesothelioma cells.

A naturally occurring stilbene, resveratrol, shows promising effects in the treatment of malignant pleural mesothelioma (MPM) both as a single agent and in combination with chemotherapeutic drugs. To discover new anticancer agents targeting MPM, stilbene-targeted isolation was performed on the roots of Polygonum multiflorum Thunb., an herbal medicine rich in stilbene compounds. In this study, seven stilbene glycosides (1-7) were isolated, along with four non-stilbenes (8-11), of which compounds 4 and 9-11 have not previously been isolated from this species. Stiquinoside A (1) is a previously undescribed stilbene glycoside, and its structure was elucidated as (E)-2,3,5,4'-tetrahydroxystilbene 2-O-ß-d-quinovopyranoside based on 1D and 2D-NMR, HR-ESI-MS, and acid hydrolysis experiments. Compounds 1, 4, 6, and 8 significantly inhibit the growth of MPM cancer cells H2452. These results demonstrate the potential utility of stilbenes in new strategies for the treatment of MPM.

Study on the differential hepatotoxicity of raw polygonum multiflorum and polygonum multiflorum praeparata and its mechanism.

BACKGROUND: Polygonum multiflorum (PM), a widely used traditional Chinese medicine herb, is divided into two forms, namely raw polygonum multiflorum (RPM) and polygonum multiflorum praeparata (PMP), according to the processing procedure. Emerging data has revealed the differential hepatotoxicity of RPM and PMP, however, its potential mechanism is still unclear. METHODS: In our study, we investigated the differential hepatotoxicity of RPM and PMP exerted in C57BL/6 mice. First, sera were collected for biochemical analysis and HE staining was applied to examine the morphological alternation of the liver. Then we treated L02 cells with 5 mg / mL of RPM or PMP. The CCK8 and EdU assays were utilized to observe the viability and proliferation of L02 cells. RNA sequencing was performed to explore the expression profile of L02 cells. Western blotting was performed to detect the expression level of ferroptosis-related protein. Flow cytometry was used to evaluate ROS accumulation. RESULTS: In our study, a significant elevation in serum ALT, AST and TBIL levels was investigated in the RMP group, while no significant differences were observed in the PMP group, compared to that of the CON group. HE staining showed punctate necrosis, inflammatory cell infiltration and structural destruction can be observed in the RPM group, which can be significantly attenuated after processing. In addition, we also found RPM could decrease the viability and proliferation capacity of L02 cells, which can be reversed by ferroptosis inhibitor. RNA sequencing data revealed the adverse effect of PM exerted on the liver is closely associated with ferroptosis. Western blotting assay uncovered the protein level of GPX4, HO-1 and FTL was sharply decreased, while the ROS content was dramatically elevated in L02 cells treated with RPM, which can be partially restored after processing. CONCLUSIONS: The hepatotoxicity induced by RPM was significantly lower than the PMP, and its potential mechanism is associated with ferroptosis.

A comprehensive investigation on the chemical changes of traditional Chinese medicine with classic processing technology: Polygonum multiflorum under nine cycles of steaming and sunning as a case study.

The processing of traditional Chinese medicine (TCM) plays an important role in the clinical application, which usually has the function of "increasing efficiency and reducing toxicity". Polygonum multiflorum (PM) has been reported to induce hepatotoxicity, while it is believed that the toxicity is reduced after processing. Studies have shown that the hepatotoxicity of PM is closely related to the changes in chemical components before and after processing. However, there is no comprehensive investigation on the chemical changes of PM during the processing progress. In this research, we established a comprehensive method to profile both small molecule compounds and polysaccharides from raw and different processed PM samples. In detail, an online two-dimensional liquid chromatography coupled with quadrupole-orbitrap mass spectrometry (2D-LC/Q-Orbitrap MS) was utilized to investigate the small molecules, and a total of 150 compounds were characterized successfully. After multivariate statistical analysis, 49 differential compounds between raw and processed products were screened out. Furthermore, an accurate and comprehensive method for quantification of differential compounds in PM samples was established based on ultra-high performance liquid chromatography/Q-Orbitrap-MS (UHPLC/Q-Orbitrap-MS) within 16 min. In addition, the changes of polysaccharides in different PM samples were analyzed, and it was found that the addition of black beans and steaming times would affect the content and composition of polysaccharides in PM significantly. Our work provided a reference basis for revealing the scientific connotation of the processing technology and increasing the quality control and safety of PM.

Characterization of the physiological parameters, effective components, and transcriptional profiles of Polygonum multiflorum Thunb. Under pH stress.

Polygonum multiflorum Thunb. is a traditional Chinese medicine with extensive distribution and robust adaptability, but comprehensive research on its acid and alkali resistance is presently lacking. This study aimed to analyze the effects of 5 months of continuous pH stress on the physiological and photosynthetic parameters of P. multiflorum, and the content of effective components. Results revealed that pH stress significantly influenced the normal growth, physiological functions, and photosynthetic indicators of P. multiflorum. At soil pH 4.5, the tubers of P. multiflorum exhibited the highest levels of 2,3,5,4'-tetrahydroxy stilbene-2-O-ß-d-glucoside (THSG) and total anthraquinones at 5.41% and 0.38%, respectively. However, increased soil pH significantly reduced the content of THSG and total anthraquinones. Reference-free transcriptome analysis was further conducted on P. multiflorum treated at pH 4.5 and 9.5, generating a total of 47,305 unigenes with an N50 of 2118 bp, of which 31,058 (65.65%) were annotated. Additionally, 2472 differentially expressed genes (DEGs) were identified. Among them, 17 DEGs associated with the biosynthesis of THSG and anthraquinones were screened. A comprehensive analysis of differential gene expression and effective component content demonstrated a significant positive correlation between the content of effective components and the 14 DEGs' expression but a negative correlation with soil pH. This study highlighted the influence of varying soil pH values on the effective component content of P. multiflorum. Specific acidic conditions proved beneficial for the synthesis and accumulation of THSG and total anthraquinones in P. multiflorum, thereby enhancing the quality of the medicinal material.

Enhanced TSG stability through co-assembly with C3G: the mechanism behind processing Polygonum multiflorum Thunb with black beans via supramolecular analysis.

Elucidating the underlying mechanism of the processing of Chinese herbal medicine (CHM) is crucial and also challenging for the modernization of Traditional Chinese Medicine (TCM). Herein, inspired by the traditional method for processing the Chinese herb Polygonum multiflorum (PM) Thunb with excipient black beans, the representative herbal components trans-2,3,5,4'-tetrahydroxystilbene 2-O-ß-D-glucopyranoside (TSG) and cyanidin-3-O-ß-glucoside (C3G) from each herbal medicine were selected to investigate the processing mechanism at the supramolecular level. The co-assemblies of TSG/C3G were found to be formed, and their structure was characterized by electronic microscopy and a small angle X-ray scattering (SAXS) technique. In addition, the supramolecular interactions between TSG and C3G were fully probed with UV-Vis, fluorescence, XRD, and NMR spectroscopy. Molecular dynamics were further performed to simulate the assembly processes of TSG and C3G. Notably, the formation of TSG/C3G co-assemblies was found to significantly enhance the stability of TSG against light, Fe3+, and simulated intestinal fluids. The co-assembly of TSG and C3G that leads to supramolecular aggregates discovered here may imply the underlying mechanism of processing PM with black beans. Our results may also suggest that a new effective form of TCM is supramolecular aggregates rather than each component.

Dianthrone derivatives from Polygonum multiflorum Thunb: Anti-diabetic activity, structure-activity relationships (SARs), and mode of action.

PTP1B plays an important role as a key negative regulator of tyrosine phosphorylation associated with insulin receptor signaling in the therapy for diabetes and obesity. In this study, the anti-diabetic activity of dianthrone derivatives from Polygonum multiflorum Thunb., as well as the structure-activity relationships, mechanism, and molecular docking were explored. Among these analogs, trans-emodin dianthrone (compound 1) enhances insulin sensitivity by upregulating the insulin signaling pathway in HepG2 cells and displays considerable anti-diabetic activity in db/db mice. By using photoaffinity labeling and mass spectrometry-based proteomics, we discovered that trans-emodin dianthrone (compound 1) may bind to PTP1B allosteric pocket at helix α6/α7, which provides fresh insight into the identification of novel anti-diabetic agents.

Comparisons of physicochemical features and hepatoprotective potentials of unprocessed and processed polysaccharides from Polygonum multiflorum Thunb.

The raw and processed Polygonum multiflorum Thunb (PM) are used to treat different diseases, and PM has also been reported to have hepatotoxic effects. Moreover, mounting evidence indicates that processed PM is less toxic than raw PM. The changes in efficacy and toxicity of PM during the processing are closely related to the changes in chemical composition. Previous studies have mainly focused on the changes of anthraquinone and stilbene glycosides during process. Polysaccharides, as main components of PM, showed many pharmacological effects, but its changes in the processing has been neglected for a long time. In this study, the polysaccharides of PM in the raw (RPMPs) and processed products (PPMPs) were determined and the liver injury model induced by acetaminophen was utilized to evaluate the impact of polysaccharides on the liver. Results showed that the heteropolysaccharides RPMPs and PPMPs both comprised Man, Rha, GlcA, GalA, Glc, Ara and Xyl, but markedly differed in polysaccharide yield, molar ratio of monosaccharide composition and Mw. In vivo analysis, results showed that demonstrated that RPMPs and PPMPs both exerted hepatoprotective effects by upregulating antioxidant enzymes and repressing lipid peroxidation. It is noteworthy that the polysaccharide yield of processed PM was seven-fold higher than that of raw PM, so it is speculated that processed PM has better hepatoprotective effects at the same dose of decoction. The present work provides an important foundation for studying the polysaccharide activity of PM and further revealing the processing mechanism of PM. This study also proposed a new hypothesis that the significant increase of polysaccharide content in processed PM may be another reason that the product PM causes less liver injury.

Exploratory Quality Control Study for Polygonum multiflorum Thunb. Using Dinuclear Anthraquinones with Potential Hepatotoxicity.

In recent years, the hepatotoxicity of Polygoni Multiflora Radix (PMR) has attracted increased research interest. Some studies suggest that anthraquinone may be the main hepatotoxic component. Most of the relevant studies have focused on the mononuclear anthraquinone component rather than binuclear anthraquinones. The hepatotoxicity of dinuclear anthraquinone (dianthrone) was investigated in a cell-based model. Next, a method for the determination of six free and total dianthonones in PMR and PMR Praeparata (PMRP) was established using ultra-high-performance liquid chromatography triple quadrupole mass spectrometry (UPLC-QQQ-MS/MS), which was then used to analyze the collected samples. The data show that four binuclear anthraquinone compounds were hepatotoxic and may be potential toxicity indicators for the safety evaluation of PMR and PMRP. Herein, we provide a theoretical basis for the improvement of PMRP quality standards.

Integrated spatially resolved metabolomics and network toxicology to investigate the hepatotoxicity mechanisms of component D of Polygonum multiflorum Thunb.

ETHNOPHARMACOLOGICAL RELEVANCE: The liver toxicity of Reynoutria multiflora (Thunb.) Moldenke. (Polygonaceae) (Polygonum multiflorum Thunb, PM) has always attracted much attention, but the related toxicity materials and mechanisms have not been elucidated due to multi-component and multi-target characteristics. In previous hepatotoxicity screening, different components of PM were first evaluated and the hepatotoxicity of component D [95% ethanol (EtOH) elution] in a 70% EtOH extract of PM (PM-D) showed the highest hepatotoxicity. Furthermore, the main components of PM-D were identified and their hepatotoxicity was evaluated based on a zebrafish embryo model. However, the hepatotoxicity mechanism of PM-D is unknown. AIM OF THE STUDY: This work is to explore the hepatotoxicity mechanisms of PM-D by integrating network toxicology and spatially resolved metabolomics strategy. MATERIALS AND METHODS: A hepatotoxicity interaction network of PM-D was constructed based on toxicity target prediction for eight key toxic ingredients and a hepatotoxicity target collection. Then the key signaling pathways were enriched, and molecular docking verification was implemented to evaluate the ability of toxic ingredients to bind to the core targets. The pathological changes of liver tissues and serum biochemical assays of mice were used to evaluate the liver injury effect of mice with oral administration of PM-D. Furthermore, spatially resolved metabolomics was used to visualize significant differences in metabolic profiles in mice after drug administration, to screen hepatotoxicity-related biomarkers and analyze metabolic pathways. RESULTS: The contents of four key toxic compounds in PM-D were detected. Network toxicology identified 30 potential targets of liver toxicity of PM-D. GO and KEGG enrichment analyses indicated that the hepatotoxicity of PM-D involved multiple biological activities, including cellular response to endogenous stimulus, organonitrogen compound metabolic process, regulation of the apoptotic process, regulation of kinase, regulation of reactive oxygen species metabolic process and signaling pathways including PI3K-Akt, AMPK, MAPK, mTOR, Ras and HIF-1. The molecular docking confirmed the high binding activity of 8 key toxic ingredients with 10 core targets, including mTOR, PIK3CA, AKT1, and EGFR. The high distribution of metabolites of PM-D in the liver of administrated mice was recognized by mass spectrometry imaging. Spatially resolved metabolomics results revealed significant changes in metabolic profiles after PM-D administration, and metabolites such as taurine, taurocholic acid, adenosine, and acyl-carnitines were associated with PM-D-induced liver injury. Enrichment analyses of metabolic pathways revealed tht linolenic acid and linoleic acid metabolism, carnitine synthesis, oxidation of branched-chain fatty acids, and six other metabolic pathways were significantly changed. Comprehensive analysis revealed that the hepatotoxicity caused by PM-D was closely related to cholestasis, mitochondrial damage, oxidative stress and energy metabolism, and lipid metabolism disorders. CONCLUSIONS: In this study, the hepatotoxicity mechanisms of PM-D were comprehensively identified through an integrated spatially resolved metabolomics and network toxicology strategy, providing a theoretical foundation for the toxicity mechanisms of PM and its safe clinical application.

Polygonum multiflorum Thunb. Induces hepatotoxicity in SD rats and hepatocyte spheroids by Disrupting the metabolism of bilirubin and bile acid.

ETHNOPHARMACOLOGICAL RELEVANCE: The liver damage associated with Polygonum multiflorum Thunb. (P. multiflorum) and its preparations have aroused widespread concern. Opinions on the toxicity mechanisms and targets of P. multiflorum vary, and the toxic components are even more controversial. However, based on the current research results, we believed that any single component in P. multiflorum could not directly lead to liver injury, but may be the synergistic effect of multiple components. In addition, the toxicity mechanism also involved multiple targets. AIM OF THE STUDY: This study aimed to elucidate the mechanism and target of the hepatotoxicity of P. multiflorum. MATERIALS AND METHODS: In this study, the manifestations of liver injury triggered by P. multiflorum and the associated metabolic enzymes/transporters in the metabolic pathways of bilirubin and bile acid were investigated to elucidate the mechanism and target of the hepatotoxicity of P. multiflorum and related components. First, the hepatotoxicity and potential effect of P. multiflorum on both metabolic pathways were studied in rats administered P. multiflorum extracts (in 70% ethanol) for 42 days. Then, in vitro cultured hepatocyte spheroids were used to determine the hepatotoxicity of monomer components. RESULTS: This revealed that P. multiflorum could simultaneously block bilirubin(BIL) and bile acid(BA) metabolism pathways, subsequently leading to liver damage. The targets and modes of action include reducing the activity of UGT1A1, the only metabolic enzyme of BIL, downregulating BIL and BA uptake transporters NTCP, OATP1B1, OATP1B3, efflux transporters MRP2, and BSEP, and upregulating efflux transporter MRP3. Furthermore, our data indicated that 2,3,5,4'-tetrahydroxystilbene-2-O-ß-glucoside (TSG) and emodin-8-O-ß-D-glucoside (EG) are the main toxic components in P. multiflorum. TSG accounts for 3.71% of the total content of P. multiflorum. In addition to markedly downregulating UGT1A1, TSG can upregulate OATP1B1/3 and promote the uptakes of bilirubin and bile acid, producing synergistic toxicity. EG accounts for 0.29% of the total content and demonstrates direct hepatotoxicity and extensive substrate overlap with bilirubin and bile acids. It can affect these two metabolic pathways simultaneously, promoting the accumulation of both bilirubin and bile acid for further toxic effects. Emodin is other major component, accounting for 0.01% of the total content, and its hepatotoxicity mechanisms include direct toxicity and inhibitory effects on bilirubin metabolizing enzymes. However, emodin is mainly distributed in the kidneys, so its hepatotoxicity risk is relatively low. CONCLUSION: The simultaneous blockade of bilirubin and bile acid metabolic pathways as the critical toxic mechanism of P. multiflorum-induced liver injury, and potential toxic components were TSG and EG.

Cysteine-Based Protein Covalent Binding and Hepatotoxicity Induced by Emodin.

Emodin (EMD) is a major ingredient of Polygonum multiflorum Thunb. (PMT), which has shown adverse liver reactions. Despite multiple pharmacological activities, EMD is reported to show various toxicities. Our early study demonstrated the reactivity of EMD to glutathione. This study aimed to determine the covalent interaction of hepatic protein with EMD and the correlation of the protein modification with hepatotoxicity induced by EMD. EMD-derived protein adduction was detected in an incubation mixture containing mouse liver homogenates and EMD. Such protein adduction was also observed in hepatic protein obtained from mice exposed to EMD. The protein covalent binding occurred in time- and dose-dependent manners. Pre-treatment of l-buthionine-sulfoximine significantly potentiated EMD-induced adduction and hepatotoxicity caused by EMD and lipopolysaccharide co-treatment. As expected, EMD-derived protein modification was observed in mouse primary hepatocytes treated with EMD. The increase in EMD exposure concentration intensified EMD-derived protein adduction and increased EMD-induced cell death. The susceptibility of hepatocytes to EMD cytotoxicity and the intensity of EMD-induced protein adduction were attenuated by the co-treatment of hepatocytes with N-acetyl cysteine. A good association of protein modification with hepatotoxicity induced by EMD was illustrated, which facilitates the understanding of the mechanism of hepatotoxicity induced by EMD.

Clinical correlation between serum cytokines and the susceptibility to Polygonum multiflorum-induced liver injury and an experimental study.

Polygonum multiflorum (PM), a popular functional food, and a herbal and dietary supplement, is widely used as a tonic in China and East Asia. In recent years, it has attracted great concern for its ability to cause idiosyncratic drug-induced liver injury (IDILI). However, identifying individuals susceptible to IDILI remains challenging. This is a prospective study. For 6 patients whose serum alanine aminotransferase (ALT) levels after consuming PM were abnormally elevated (susceptible group), 15 patients with normal levels of liver injury markers were matched (tolerant group) based on similar baseline characteristics. ProcartaPlex immunoassays were adopted to quantitatively detect 33 serum cytokines in the two groups of patients before consuming PM, to characterize the cytokine profile and screen differential cytokines. Subsequently, the susceptibility of a potential biomarker to regulate PM-induced liver injury was validated in animal models. There were significant differences in the cytokine profiles between the susceptible and tolerant groups, wherein the susceptible patients showed immune perturbation characterized by high expression of multiple inflammatory cytokines, especially the proinflammatory cytokine TNF-α (P = 0.006). Among them, the cytokine TNF-α had the strongest correlation with ALT, where the correlation coefficient was greater than 0.6, and the area under the receiver operating characteristic curve was more than 0.8. Animal experiments revealed that both PM water extract and its susceptibility component of liver injury, cis-stilbene glucoside, could cause liver injury in the mice pre-stimulated using TNF-α. Conversely, administration of the same dose of drugs on control mice did not show any hepatotoxicity. In conclusion, immune perturbation mainly mediated by TNF-α may regulate the susceptibility to PM-induced liver injury. This provides a new perspective for the study of susceptibility to IDILI.

The effect of emodin on melanogenesis through the modulation of ERK and MITF signaling pathway.

The aim of this study was to investigate the effect of emodin derived from Polygonum multiflorum on melanin production in B16F1 cells. In this study, emodin did not show antioxidant activity in DPPH radical and reducing power assays. However, it was found that emodin scavenged intracellular H2O2. Emodin increased not only tyrosinase activity but also melanin synthesis in vitro. Moreover, emodin enhanced melanin synthesis by increasing the expression level of tyrosinase (TYR), tyrosine related protein (TRP)-1, TRP-2, MITF and SIRT1 proteins in live cells treated with H2O2 compared with H2O2 treatment group in the analyses of western blot and immunofluorescence. Moreover, emodin suppressed ERK activation by SIRT1 and FOXO1. Thus, emodin promoted melanin synthesis by increasing the expression of TRP-1, TRP-2, tyrosinase through the activation of MITF transcription factor. These findings suggest that emodin could promote melanin production related to anti-hair graying.

Discovery of Hepatotoxic Equivalent Markers and Mechanism of Polygonum multiflorum Thunb. by Metabolomics Coupled with Molecular Docking.

Polygonum multiflorum Thunb. (PMT), a commonly used Chinese herbal medicine for treating diseases such as poisoning and white hair, has attracted constant attention due to the frequent occurrence of liver injury incidents. To date, its hepatotoxic equivalent markers (HEMs) and potential hepatotoxic mechanisms are still unclear. In order to clarify the HEMs of PMT and further explore the potential mechanisms of hepatotoxicity, firstly, the chemical constituents in PMT extract were globally characterized, and the fingerprints of PMT extracts were established along with the detection of their hepatotoxicity in vivo. Then, the correlations between hepatotoxic features and component contents were modeled by chemometrics to screen HEMs of PMT, which were then further evaluated. Finally, the hepatotoxic mechanisms of PMT were investigated using liver metabolomics and molecular docking. The results show that the chemical combination of 2,3,5,4-tetrahydroxystilbene-2-O-ß-D-glucoside (TSG) and emodin-8-O-glucoside (EG) was discovered as the HEMs of PMT through pre-screening and verifying process. Liver metabolomics revealed that PMT caused liver injury by interfering with purine metabolism, which might be related to mitochondrial function disorder and oxidative injury via the up-regulations of xanthosine and xanthine, and the down-regulation of 5' nucleotidase (NT5E) and adenylate kinase 2 (AK2). This study not only found that the HEMs of PMT were TSG and EG, but also clarified that PMT might affect purine metabolism to induce liver injury, which contributed to our understanding of the underlying mechanisms of PMT hepatotoxicity.

Greener Is Better: First Approach for the Use of Natural Deep Eutectic Solvents (NADES) to Extract Antioxidants from the Medicinal Halophyte Polygonum maritimum L.

In this study, natural deep eutectic solvents (NADES) formed by choline chloride (ChCl), sucrose, fructose, glucose, and xylose, were used to extract antioxidants from the halophyte Polygonum maritimum L. (sea knotgrass) and compared with conventional solvents (ethanol and acetone). NADES and conventional extracts were made by an ultrasound-assisted procedure and evaluated for in vitro antioxidant properties by the radical scavenging activity (RSA) on the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, oxygen radical absorbance capacity (ORAC), and copper chelating activity (CCA). Samples were profiled by liquid chromatography (LC)-electrospray ionization (ESI)-QTOF-MS analysis. ChCl:fructose was more efficient in the DPPH assay, than the acetone extract. ChCl:sucrose and ChCl:fructose extracts had the highest ORAC when compared with the acetone extract. NADES extracts had higher CCA, than the acetone extract. The phenolic composition of the NADES extracts was less complex than the conventional extracts, but the proportions of major antioxidants, such as flavonols and flavan-3-ols, were similar in all the solvents. Myricitrin was the major flavonoid in all of the samples, while gallic acid was the main phenolic acid in the conventional extracts and present in a greater amount in ChCl:fructose. Results suggest that NADES containing ChCl and sucrose/fructose can replace conventional solvents, especially acetone, in the extraction of antioxidants from sea knotgrass.

High-Throughput Identification of Organic Compounds from Polygoni Multiflori Radix Praeparata (Zhiheshouwu) by UHPLC-Q-Exactive Orbitrap-MS.

Polygoni Multiflori Radix Praeparata (PMRP), as the processed product of tuberous roots of Polygonum multiflorum Thunb., is one of the most famous traditional Chinese medicines, with a long history. However, in recent years, liver adverse reactions linked to PMRP have been frequently reported. Our work attempted to investigate the chemical constituents of PMRP for clinical research and safe medication. In this study, an effective and rapid method was established to separate and characterize the constituents in PMRP by combining ultra-high performance liquid chromatography with hybrid quadrupole-orbitrap mass spectrometry (UHPLC-Q-Exactive Orbitrap-MS). Based on the accurate mass measurements for molecular and characteristic fragment ions, a total of 103 compounds, including 24 anthraquinones, 21 stilbenes, 15 phenolic acids, 14 flavones, and 29 other compounds were identified or tentatively characterized. Forty-eight compounds were tentatively characterized from PMRP for the first time, and their fragmentation behaviors were summarized. There were 101 components in PMRP ethanol extract (PMRPE) and 91 components in PMRP water extract (PMRPW). Simultaneously, the peak areas of several potential xenobiotic components were compared in the detection, which showed that PMRPE has a higher content of anthraquinones and stilbenes. The obtained results can be used in pharmacological and toxicological research and provided useful information for further in vitro and in vivo studies.