Emodin inhibits bladder inflammation and fibrosis in mice with interstitial cystitis by regulating JMJD3

Purpose: Interstitial cystitis/bladder pain syndrome (IC/BPS) is a devastating urological chronic pelvic pain condition. In search of a potential treatment, we investigated the effect of emodin on IC/BPS inflammation and fibrosis, and explore the potential mechanism. Methods: An experimental model of interstitial cystitis was induced by cyclophosphamide, and human bladder smooth muscle cells were treated with lipopolysaccharide to establish the cell model in vitro. In both models, inflammation- and fibrosis-related indexes were measured after emodin administration. Furthermore, the specific antagonists were used to dig for the mechanisms underlying the response to emodin treatment. Results: Emodin significantly ameliorated management of cystitis, reduced the amount of inflammatory cytokines (tumor necrosis factor-α, monocyte chemoattractant protein-1, interleukin-1ß, interleukin-8, and interleukin-6) in models, as well as reducing the synthesis of fibrosis marker including collagen1, collagen3, vimentin, fibronectin and α-smooth muscle actin. Further mechanism studies demonstrated that emodin inhibited inflammatory reaction and fibrosis through blocking lysine-specific demethylase 6B (JMJD3) expression via JAK/STAT, NF-κB and TGF-ß/SMAD pathways. Conclusions: Our study reveals the critical role of emodin-JMJD3 signaling in interstitial cystitis by regulating inflammation, fibrosis, and extracellular matrix deposition in cells and tissues, and these findings provide an avenue for effective treatment of patients with cystitis.

Spectrum-effect relationship of total anthraquinone extract of Cassia seeds against fluorouracil-induced liver injury in mice / 南方医科大学学报

OBJECTIVE@#To investigate the spectrum-effect relationship between the total anthraquinone extract of Cassia seeds and fluorouracil (5-Fu)-induced liver injury in mice and identify the effective components in the extract.@*METHODS@#A mouse model of liver injury was established by intraperitoneal injection of 5-Fu, with bifendate as the positive control. The serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and myeloperoxidase (MPO), superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) in the liver tissue were detected to investigate the effect of the total anthraquinone extract of Cassia seeds (0.4, 0.8 and 1.6 g/kg) on liver injury induced by 5-Fu. HPLC fingerprints of 10 batches of the total anthraquinone extracts were established to analyze the spectrum- effectiveness of the extract against 5- Fu- induced liver injury in mice and screen the effective components using the grey correlation method.@*RESULTS@#The 5- Fu- treated mice showed significant differences in liver function parameters from the normal control mice (P < 0.05), suggesting successful modelling. Compared with those in the model group, serum ALT and AST activities were decreased, SOD and T- AOC activities significantly increased, and MPO level was significantly lowered in the mice treated with the total anthraquinone extract (all P < 0.05). HPLC fingerprints of the 31 components in the total anthraquinone extract of Cassia seeds showed good correlations with the potency index of 5-Fu-induced liver injury but with varying correlation strengths. The top 15 components with known correlations included aurantio-obtusina (peak 6), rhein (peak 11), emodin (peak 22), chrysophanol (peak 29) and physcion (peak 30).@*CONCLUSION@#The effective components in the total anthraquinone extract of Cassia seeds, including aurantio-obtusina, rhein, emodin, chrysophanol, and physcion, are coordinated to produce protective effects against 5-Fu-induced liver injury in mice.

Variation and interaction mechanism between active components in Rheum officinale and rhizosphere soil microorganisms under drought stress / 中国中药杂志

To explore the changes and the reaction mechanisms between soil microecological environment and the content of secon-dary metabolites of plants under water deficit, this study carried out a pot experiment on the 3-leaf stage seedlings of Rheum officinale to analyze their response mechanism under different drought gradients(normal water supply, mild, moderate, and severe drought). The results indicated that the content of flavonoids, phenols, terpenoids, and alkaloids in the root of R. officinale varied greatly under drought stresses. Under mild drought stress, the content of substances mentioned above was comparatively high, and the content of rutin, emodin, gallic acid, and(+)-catechin hydrate in the root significantly increased. The content of rutin, emodin, and gallic acid under severe drought stress was significantly lower than that under normal water supply. The number of species, Shannon diversity index, richness index, and Simpson index of bacteria in the rhizosphere soil were significantly higher than those in blank soil, and the number of microbial species and richness index decreased significantly with the aggravation of drought stresses. In the context of water deficit, Cyanophyta, Firmicutes, Actinobacteria, Chloroflexi, Gemmatimonadetes, Streptomyces, and Actinomyces were the dominant bacteria in the rhizosphere of R. officinale. The relative content of rutin and emodin in the root of R. officinale was positively correlated with the relative abundance of Cyanophyta and Firmicutes, and the relative content of(+)-catechin hydrate and(-)-epicatechin gallate was positively correlated with the relative abundance of Bacteroidetes and Firmicutes. In conclusion, appropriate drought stress can increase the content of secondary metabolites of R. officinale from physiological induction and the increase in the association with beneficial microbe.

Mechanism of emodin in relieving neuropathic pain by regulating serum metabolism / 中国中药杂志

The present study investigated the effect of emodin on the serum metabolite profiles in the chronic constriction injury(CCI) model by non-target metabolomics and explored its analgesic mechanism. Twenty-four Sprague Dawley(SD) rats were randomly divided into a sham group(S), a CCI group(C), and an emodin group(E). The rats in the emodin group were taken emodin via gavage once a day for fifteen days(50 mg·kg~(-1)) on the first day after the CCI surgery. Mechanical withdrawal threshold(MWT) and thermal withdrawal threshold(TWL) in each group were performed before the CCI surgery and 3,7, 11, and 15 days after surgery. After 15 days, blood samples were collected from the abdominal aorta. The differential metabolites were screened out by non-target metabolomics and analyzed with Kyoto Encyclopedia of Genes and Genomes(KEGG) and ingenuity pathway analysis(IPA). From the third day after CCI surgery, the MWT and TWL values were reduced significantly in both CCI group and emodin group, compared with the sham group(P<0.01). At 15 days post-surgery, the MWT and TWL values in emodin group increased significantly compared with the CCI group(P<0.05). As revealed by non-target metabolomics, 72 differential serum metabolites were screened out from the C-S comparison, including 41 up-regulated and 31 down-regulated ones, while 26 differential serum metabolites from E-C comparison, including 10 up-regulated and 16 down-regulated ones. KEGG analysis showed that the differential metabolites in E-C comparison were enriched in the signaling pathways, such as sphingolipid metabolism, arginine biosynthesis, glycerophospholipid metabolism, and tryptophan metabolism. IPA showed that the differential metabolites were mainly involved in the lipid metabolism-molecular transport-small molecule biochemistry network. In conclusion, emodin can exert an analgesic role via regulating sphingolipid metabolism and arginine biosynthesis.

Formulation optimization of emodin nanostructured lipid carriers by Box-Behnken response surface method and in vitro quality evaluation / 中国中药杂志

Emodin nanostructured lipid carriers(ED-NLC) were prepared and their quality was evaluated in vitro. Based on the results of single-factor experiments, the ED-NLC formulation was optimized by Box-Behnken response surface method with the dosages of emodin, isopropyl myristate and poloxamer 188 as factors and the nanoparticle size, encapsulation efficiency and drug loading as evaluation indexes. Then the evaluation was performed on the morphology, size and in vitro release of the nanoparticles prepared by emulsification-ultrasonic dispersion method in line with the optimal formulation, i.e., 3.27 mg emodin, 148.68 mg isopropyl myristate and 173.48 mg poloxamer 188. Under a transmission electron microscope(TEM), ED-NLC were spherical and their particle size distribution was uniform. The particle size of ED-NLC was(97.02±1.55) nm, the polymer dispersion index 0.21±0.01, the zeta potential(-38.96±0.65) mV, the encapsulation efficiency 90.41%±0.56% and the drug loading 1.55%±0.01%. The results of differential scanning calorimeter(DSC) indicated that emodin may be encapsulated into the nanostructured lipid carriers in molecular or amorphous form. In vitro drug release had obvious characteristics of slow release, which accorded with the first-order drug release equation. The fitting model of Box-Behnken response surface methodology was proved accurate and reliable. The optimal formulation-based ED-NLC featured concentrated particle size distribution and high encapsulation efficiency, which laid a foundation for the follow-up study of ED-NLC in vivo.

Therapeutic mechanism of emodin for treatment of rheumatoid arthritis: a network pharmacology-based analysis / 南方医科大学学报

OBJECTIVE@#To investigate the therapeutic mechanism of emodin in the treatment of rheumatoid arthritis (RA) using a network pharmacology-based method and validate this mechanism in a fibroblast-like synovial cell line.@*METHODS@#The PubChem, Targetnet, SwissTargetPrediction, Genecards, OMIM, and DisGeNET databases were searched to obtain emodin targets and RA-related genes. A protein-protein interaction (PPI) network was constructed, and GO and KEGG pathway enrichment analyses were carried out to analyze the intersection genes. AutoDock4.2.6 software was used to simulate molecular docking between emodin and its candidate targets. In a cultured fibroblast-like synovial cell line (MH7A), the effects of different concentrations of emodin on proliferation of tumor necrosis factor-α (TNF-α)-induced cells were investigated using CCK-8 assay, cell scratch experiment and flow cytometry; the changes in the expressions of nuclear factor-κB (NF-κB) pathway proteins were detected using Western blotting, and the mRNA expressions of the hub genes were examined with RT-qPCR.@*RESULTS@#We identified 32 intersection genes of emodin and RA, and the key targets including CAPS3, ESR1, and MAPK14 involved mainly the NF-κB signaling pathway. Cell scratch experiment and flow cytometry demonstrated a strong inhibitory effect of emodin on MH7A cell proliferation. Treatment with TNF-α significantly increased the cellular expressions of the NF-κB pathway proteins, which were obviously lowered by treatment with 80 μmol/L emodin. The results of RT-qPCR showed that TNF-α treatment obviously up-regulated the expressions of the hub genes COX2 and P38MAPK, and emodin treatment significantly down-regulated the expressions of MAPK and PTGS2 and up-regulated the expression of CASP3.@*CONCLUSION@#The therapeutic effect of emodin on RA is mediated mainly through regulation of cell proliferation, apoptosis, and the NF-κB pathway.

Emodin alleviates hypertrophic scar formation by suppressing macrophage polarization and inhibiting the Notch and TGF-β pathways in macrophages

Hypertrophic scar (HS) formation is a common complication that develops after skin injury; however, there are few effective and specific therapeutic approaches for HS. Emodin has previously been reported to inhibit mechanical stress-induced HS inflammation. Here, we investigated the molecular mechanisms underlying the inhibitory effects of emodin on HS formation. First, we conducted in vitro assays that revealed that emodin inhibited M1 and M2 polarization in rat macrophages. We subsequently established a combined rat model of tail HS and dorsal subcutaneous polyvinyl alcohol (PVA) sponge-induced wounds. Rats were treated with emodin or vehicle (DMEM). Tail scar specimens were harvested at 14, 28, and 42 days post-incision and subjected to H&E staining and Masson's trichrome staining. Histopathological analyses confirmed that emodin attenuated HS formation and fibrosis. Macrophages were separated from wound cells collected from the PVA sponge at 3 and 7 days after implantation. Flow cytometry analysis demonstrated that emodin suppressed in vivo macrophage recruitment and polarization at the wound site. Finally, we explored the molecular mechanisms of emodin in modulating macrophage polarization by evaluating the expression levels of selected effectors of the Notch and TGF-β pathways in macrophages isolated from PVA sponges. Western blot and qPCR assays showed that Notch1, Notch4, Hes1, TGF-β, and Smad3 were downregulated in response to emodin treatment. Taken together, our findings suggested that emodin attenuated HS formation and fibrosis by suppressing macrophage polarization, which is associated with the inhibition of the Notch and TGF-β pathways in macrophages.

Effects of Emodin Derivative on Cell Cycle, Apoptosis and NF-κB Pathway in Burkitt Lymphoma Cells / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect and mechanism of a novel emodin derivative YX-18 on Burkitt lymphoma (BL) cells.@*METHODS@#MTT assay was used to detect the effect of YX-18 on the proliferation of BL cell lines CA46 and Raji. Annexin V-PE/7-AAD double staining assay was used for detecting the effect of YX-18 on the apoptosis of CA46 and Raji cells. PI/RNase staining was used to test the effect of YX-18 on CA46 and Raji cell cycle. JC-1 method was used to measure the changes of mitochondrial membrane potential after YX-18 treatment, and DAPI staining was used to detect the morphology of apoptotic cells. Western blot was used to analyze the distribution changes of NF-κB pathway protein (P65, P-P65, IκB, P-IκB) in the cytoplasm and cell nucleus, and also the expression changes of cyclin-related protein P21, CDK2, P-CDK2, Cycling D1, Cycling E1, and the apoptosis-related protein Caspase-3, Caspase-8, Caspase-9 and the proliferation-related protein C-MYC, BCL-2 by YX-18. Real-time fluorescence-quantitative PCR was used to evaluate the effects of YX-18 on mRNA levels of C-MYC and Ki-67 genes in CA46 and Raji cells, and EBNA-1 and EBER genes of EBV in Raji (EBV@*RESULTS@#Novel Emodin derivative YX-18 could effectively inhibit the proliferation of BL cell lines CA46 and Raji, showing a time-dependent effect (24, 48 and 72 h: r@*CONCLUSION@#The novel emodin derivative YX-18 can significantly inhibit the proliferation of Burkitt lymphoma cells, and induce the cell apoptosis and cycle arrest. The inhibitory effect of YX-18 on the proliferation of Burkitt lymphoma cells may be related with the effect of Caspase apoptosis pathway, the proliferation and apoptosis-related molecules, such as C-MYC and Ki-67, and also to the inhibition of NF-κB pathway.

Study on potential hepatotoxicity of main monomers of Polygonum multiflorum based on liver micro-tissue / 中国中药杂志

In this study, we aimed to establish a rat liver micro-tissue evaluation system to evaluate the hepatotoxicity of the main monomers in Polygonum multiflorum. Rat primary hepatocytes were isolated and purified by two-step in situ perfusion method to prepare hepatic parenchymal cells. The ultra-low adsorption plate and the inverted model were used to establish an in vitro hepatotoxicity evaluation system. After the system was established, the main monomer components(monanthone with emodin type, rhein, emodin, emodin-8-O-β-D-glucopyranoside, physcion) of P. multiflorum were selected for in vitro hepatotoxicity evaluation. This study showed that the primary cells of the liver can form liver micro-tissues in the low adsorption plate method and the mold perfusion method, with good liver structure and function, which can be used to evaluate the hepatotoxicity of the drug to be tested after long-term administration. The five monomers to be tested in P. multiflorum can significantly affect the proliferation of primary liver micro-tissues in rats in a dose-and time-dependent manner. The hepatotoxic effects were as follows: monanthone with emodin type > rhein > emodin > emodin-8-O-β-D-glucopyranoside > physcion. The results suggested that the emodin-type monoterpene and rhein might be the potential hepatotoxic components, while the metabolites of emodin-8-O-β-D-glucoside and emodin methyl ether showed more toxic risks. The rat primary hepatocyte micro-tissue model system established in this experiment could be used to achieve long-term drug administration in vitro, which was consistent with the clinical features of liver injury caused by long-term use of P. multiflorum. The experimental results provided important information and reference on the clinical application and toxic component of P. multiflorum.

Effects of emodin on lipid accumulation and inflammation in hepatocytes / 中国中药杂志

The aim of this study was to explore the effect of emodin on lipid accumulation and inflammation in hepatocytes. The cell morphology was observed by microscopy. LDH release was detected by the kit. Levels of intracellular lipid droplets were observed by oil red O staining. The contents of TC and TG in cells were detected by the kit. Western blot was used to determine protein expressions of FASN,SREBF2,APOB,IL-6 and p-NF-κB in hepatocytes. The results showed that the levels of L02 cell LDH were significantly increased after being treated with emodin,and the cells showed shrinkage,volume reduction,decrease in quantity with the increase of dose. Red lipid droplets were observed in L02 hepatocytes. Intracellular TC and TG contents of L02 cell increased in a concentrationdependent manner,with significant differences between medium and high-dose groups( P < 0. 05). Protein expressions of FASN,SREBF2,IL-6 and p-NF-κB were significantly higher than those of the control group,and the expression level of APOB was significantly lower than that of the control group( P<0. 05). In conclusion,emodin could induce lipid accumulation and inflammatory damage in hepatocytes in a dose-dependent manner,which in turn could damage liver cells. This process was related to the up-regulation of FASN,SREBF2,IL-6,p-NF-κB,as well as the down-regulation of the protein expression of APOB.

Effect of emodin on gut microbiota of rats with acute kidney failure / 中国中药杂志

The aim of this paper was to investigate the effect of emodin on gut microbiota in acute kidney injury rats( AKI). Rats were randomly divided into several groups: normal group,model group,low-dose of emodin group( 10 mg·kg~(-1)),medium-dose of emodin group( 25 mg·kg~(-1)),high-dose of emodin group( 50 mg·kg~(-1)) and control group( 5 mg·kg~(-1) of benazepril hydrochloride).The AKI model rats were established by intraperitoneal injection of small dose of gentamicin sulfate for 7 days. Two hours after intraperitoneal injection,except for the normal group and the model group,the other groups were given corresponding doses of drugs for 15 days. The serum levels of serum creatinine( SCr),urea nitrogen( BUN),plasma endotoxin level,24 h urinary protein and D-lactate in the plasma were determined by sarcosine oxidase,urease method,tal reagent method,bromo cresol chloroform method and double antibody sandwich enzyme-linked immunoadsorbent assay,respectively. Gut microbial communities were assayed by fluorescent quantitative PCR methods. HE staining was used to detect the pathological changes of the kidneys. Compared with the normal group,there were significant differences in body weight,urinary protein( UTP),bacterial endotoxin,urea nitrogen,creatinine,D-lactate in the plasma and four bacterial contents in the model group( P<0. 05). The urinary protein,urea nitrogen,D-lactate,creatinine and plasma bacterial endotoxin in control group and each emodin group were lower than those in model group,especially for high-dose of emodin( P<0. 01). Moreover,pathology resolution in high-dose emodin was better than other groups. Except for low-dose of emodin group,qRT-PCR data suggested that the amounts of Escherichia coli and Enterococcus in medication administration group were increased,while the amounts of Lactobacilli and Bifidobacterium were reduced compared with model group( P<0. 05),especially for high-dose of emodin( P<0. 01). There is a clear imbalance of gut microbiota in rats with AKI. Emodin could regulate the imbalance of gut microbiota,which might be one of the mechanisms of its effects on AKI rats.

Emodin exerts protective effect against palmitic acid-induced endoplasmic reticulum stress in HepG2 cells / 한국영양학회지

PURPOSE: Protein overloading in the endoplasmic reticulum (ER) leads to endoplasmic reticulum stress, which exacerbates various disease conditions. Emodin, an anthraquinone compound, is known to have several health benefits. The effect of emodin against palmitic acid (PA) - induced ER stress in HepG2 cells was investigated. METHODS: HepG2 cells were treated with varying concentrations of palmitic acid to determine the working concentration that induced ER stress. ER stress associated genes such as ATF4, XBP1s, CHOP and GRP78 were checked using RT- PCR. In addition, the expression levels of unfolded protein response (UPR) associated proteins such as IRE1α, eIF2α and CHOP were checked using immunoblotting to confirm the induction of ER stress. The effect of emodin on ER stress was analyzed by treating HepG2 cells with 750 µM palmitic acid and varying concentrations of emodin, then analyzing the expression of UPR associated genes. RESULTS: It was evident from the mRNA and protein expression results that palmitic acid significantly increased the expression of UPR associated genes and thereby induced ER stress. Subsequent treatment with emodin reduced the mRNA expression of ATF4, GRP78, and XBP1s. Furthermore, the protein levels of p-IRE1α, p-elF2α and CHOP were also reduced by the treatment of emodin. Analysis of sirtuin mRNA expression showed that emodin increased the levels of SIRT4 and SIRT7, indicating a possible role in decreasing the expression of UPR-related genes. CONCLUSION: Altogether, the results suggest that emodin could exert a protective effect against fatty acid-induced ER stress and could be an agent for the management of various ER stress related diseases.

Inhibition of tamoxifen's therapeutic effects by emodin in estrogen receptor-positive breast cancer cell lines

PURPOSE: This study was aimed to investigate the combination effect of endoxifen and emodin on estrogen receptor (ER) positive breast cancer cell lines and to explain the mechanism of the combination effect. METHODS: We conducted this study on MCF-7 (ER+/human epidermal growth factor receptor-2 [HER2]−), T47D (ER+/HER2−), ZR-75-1 (ER+/HER2+), and BT474 (ER+/HER2+) cell lines, which confirmed combination effect of endoxifen and emodin. Optimal concentrations for combination were determined to study the effects on proliferation of MCF-7 and ZR-75-1 cells. Analysis of the combination effect was carried out in the CompuSyn software. The combination of downstream mechanisms, and combined effects of other similar compounds were tested on the MCF-7 and ZR 75-1 cell lines. Protein expression was confirmed by western blot. RESULTS: The combination of endoxifen and emodin had antagonistic effects on MCF-7 and ZR-75-1cell lines (combination index > 1). We validated the antagonistic effect in T47D and BT474 cell lines. During the combined treatment, the results showed elevated amounts of cyclin D1 and phosphorylated extracellular signal-regulated kinase (pERK). Analysis of drug interactions showed antagonistic effect between endoxifen and chemical compounds similar to emodin, such as chrysophanol or rhein, in MCF-7 and ZR-75-1 cells. CONCLUSION: Addition of emodin attenuated tamoxifen's treatment effect via cyclin D1 and pERK up-regulation in ER-positive breast cancer cell lines.

Assessment of the Purity of Emodin by Quantitative Nuclear Magnetic Resonance Spectroscopy and Mass Balance

Quantitative nuclear magnetic resonance (qNMR) is a well-established method adopted by international pharmacopoeia for quantitative and purity analyses. Emodin is a type of anthraquinone, well known as the main active component of Fabaceae, Polygonaceae and Rhamnaceae. Purity analysis of emodin is usually performed by using the high-performance liquid chromatography (HPLC)-UV method. However, it cannot detect impurities such as salts, volatile matter, and trace elements. Using the qNMR method, it is possible to determine the compound content as well as the nature of the impurities. Several experimental parameters were optimized for the quantification, such as relaxation delay, spectral width, number of scans, temperature, pulse width, and acquisition time. The method was validated, and the results of the qNMR method were compared with those obtained by the HPLC and mass balance analysis methods. The qNMR method is specific, rapid, simple, and therefore, a valuable and reliable method for the purity analysis of emodin.

Study on hepatotoxicity of physcion based on liver metabolism in vitro / 中国中药杂志

To evaluate the hepatotoxicity risks of physcion on the basis of the bilirubin metabolism mediated by glucuronidation of UDP-glucuronosyltransferases 1A1(UGT1A1 enzyme). The monomers were added into the rat liver microsomes to test the hepatotoxicity by using bilirubin as UGT1A1 enzyme substrate, with apparent inhibition constant K_i as the evaluation index. Liver microsome incubation in vitro was adopted to initiate phase Ⅱ metabolic reaction and investigate the inhibitory effect of physcion. Then the phase Ⅰ and Ⅱ metabolic reactions were initiated to investigate the comprehensive inhibition of metabolites and prototype components. The results showed that when only the phase Ⅱ reaction was initiated, physcion directly acted on the UGT1A1 enzyme in a prototype form, exhibited weak inhibition and the inhibition type was mixed inhibition; When the phase Ⅰ and Ⅱ reactions were initiated simultaneously, the inhibitory effects of physcion on UGT1A1 enzyme became strong and the inhibition type was mixed inhibition, suggesting that physcion had phase Ⅰ and Ⅱ metabolic processes, and the metabolites had strong inhibitory effect on UGT1A1 enzyme. This experiment preliminarily proved that the metabolites of physcion may be the main components to induce hepatotoxicity.

Emodin protects H9c2 cells from hypoxia-induced injury by up-regulating miR-138 expression

Myocardial infarction (MI) is a common presentation for ischemic heart disease, which is a leading cause of death. Emodin is a Chinese herbal anthraquinone used in several diseases. However, the effect of emodin in hypoxia-induced injury in cardiomyocytes has not been clearly elucidated. Our study aimed to clarify the functions of emodin in hypoxia-induced injury in rat cardiomyocytes H9c2 and explore the underlying mechanism. The effects of emodin on cell viability and apoptosis were analyzed by the Cell counting kit-8 assay and flow cytometry assay, respectively. The cell proliferation- and cell apoptosis-related proteins were detected by western blot. qRT-PCR was used to determine the relative expression of miR-138. Cell transfection was performed to alter miR-138 and MLK3 expression. miR-138 target was performed by dual luciferase activity assay. Sirt1/AKT and Wnt/β-catenin pathways-related factors phosphorylation were analyzed by western blot. Emodin inhibited hypoxia-induced injury in H9c2 cells by promoting cell viability and reducing cell apoptosis. miR-138 was down-regulated by hypoxia treatment but up-regulated by emodin. Up-regulation of miR-138 alleviated hypoxia-induced cell injury. Down-regulation of miR-138 attenuated the growth-promoting effect of emodin on hypoxia-induced injury, whereas up-regulation of miR-138 enhanced the growth-promoting effects of emodin. The underlying mechanism might be by inactivating Sirt1/AKT and Wnt/β-catenin pathways. MLK3 was negatively regulated by miR-138 expression and inactivated Sirt1/AKT and Wnt/β-catenin pathways. Emodin alleviated hypoxia-induced injury in H9c2 cells via up-regulation of miR-138 modulated by MLK3, as well as by activating Sirt1/AKT and Wnt/β-catenin pathways.

Research on period of validity of emodin standard solution and chrysophanol standard solution / 中国中药杂志

In order to study the storage and period of validity of emodin standard solution and chrysophanol standard solution in this study, the content of emodin and chrysophanol was determined by HPLC through classical constant temperature test, and the change rule of the content of the standard solution was studied, which could be applied to standardize the management of the standard substance of traditional Chinese medicine. The results showed that the content of emodin and chrysophanol standard solution matched with the first order reaction rule. Under the storage condition of 10 °C, the change rate constant of emodin and chrysophanol were Ke=4.661 7×10⁻⁷ and Kc=4.438 9×10⁻⁷, respectivedy; and the period of validity of emodin standard solution and chrysophanol standard solution were 1 806 d and 1 896 d respectively. The determination and standardization of the period of validity of the standard solution will not only help to reduce the loss of the standard substance and save the cost of drug testing, but also help to standardize the use of the standard substance, which will contrite to obtain more accurate and satisfactory experimental results, and provide a basis for the setting of the storage period and standardized management of the reference solution of Chinese medicine.

Enhanced absorption and inhibited metabolism of emodin by 2, 3, 5, 4'-tetrahydroxystilbene-2-O-β-D-glucopyranoside: Possible mechanisms for Polygoni Multiflori Radix-induced liver injury / 中国天然药物

Polygoni Multiflori Radix (PMR) has been commonly used as a tonic in China for centuries. However, PMR-associated hepatotoxicity is becoming a safety issue. In our previous in vivo study, an interaction between stilbenes and anthraquinones has been discovered and a hypothesis is proposed that the interaction between stilbene glucoside-enriching fraction and emodin may contribute to the side effects of PMR. To further support our previous in vivo results in rats, the present in vitro study was designed to evaluate the effects of 2, 3, 5, 4'-tetrahydroxystilbene-2-O-β-D-glucopyranoside (TSG) on the cellular absorption and human liver microsome metabolism of emodin. The obtained results indicated that the absorption of emodin in Caco-2 cells was enhanced and the metabolism of emodin in human liver microsomes was inhibited after TSG treatment. The effects of the transport inhibitors on the cellular emodin accumulation were also examined. Western blot assay suggested that the depressed metabolism of emodin could be attributed to the down-regulation of UDP-glucuronosyltransferases (UGTs) 1A8, 1A10, and 2B7. These findings definitively demonstrated the existence of interaction between TSG and emodin, which provide a basis for a better understanding of the underlying mechanism for PMR-induced liver injury.

In vivo and in vitro anti-sepsis effects of physcion 8-O-β-glucopyranoside extracted from Rumex japonicus / 中国天然药物

The present study was designed to investigate the anti-sepsis effects of physcion 8-O-β-glucopyranoside (POG) isolated from Rumex japonicas and explore its possible pharmacological mechanisms. POG was extracted from R. japonicas by bioactivity-guided isolation with the anti-sepsis agents. Survival analysis in septic mouse induced by LPS and heat-killed Escherichia coli were used to evaluate the protective effect of POG (40 mg·kg, i.p.) on sepsis. Cytokines including TNF-α, IL-1β and IL-6 in RAW 264.7 cells induced by LPS (100 ng·mL) were determined by ELISA. In addition, the proteins expressions of TLR2 and TLR4 were determined by Western blotting assay. Our results demonstrated that POG (40 mg·kg, i.p.) possessed significant protective activity on the endotoxemic mice. The POG treatment (20, 40, and 80 μg·mL) significantly decreased the TNF-α, IL-1β and IL-6 induced by LPS (P < 0.01) in a concentration-dependent manner. Furthermore, the TLR4 and TLR2 proteins were also down-regulated by POG at 20 (P < 0.01), 40 (P < 0.01), and 80 μg·mL (P < 0.01). The present study demonstrated that the POG extracted from R. japonicas possessed significant anti-sepsis effect on endotoxemic mice, and can be developed as a novel drug for treating sepsis in the future.

Protective effect of emodin pretreatment in young rats with intrahepatic cholestasis / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the protective effect of emodin in young rats with intrahepatic cholestasis.</p><p><b>METHODS</b>A total of 120 young Sprague-Dawley rats were randomly divided into control, model, and high-, medium-, and low-dose emodin groups, with 24 rats in each group. The rats in the control and model groups were given sodium carboxymethyl cellulose solution by gavage, while the other groups were given different doses of emodin solution by gavage. On the 5th day of experiment, alpha-naphthylisothiocyanate (ANIT, 50 mg/kg) was applied by gavage to establish the model of intrahepatic cholestasis in all groups except the control group. At 24, 48, and 72 hours after gavage, 8 rats in each group were sacrificed. Colorimetry was used to measure the serum levels of total bilirubin (TBIL), direct bilirubin (DBIL), total bile acid (TBA), alkaline phosphatase (ALP), gamma glutamyl transpeptidase (GGT), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) in each group, and hematoxylin-eosin staining was applied to observe the morphological changes of the liver under a light microscope at different time points.</p><p><b>RESULTS</b>Compared with the control group, the model group had significantly increased serum levels of TBIL, DBIL, TBA, ALP, GGT, ALT, and AST at the 24-hour, 48-hour, and 72-hour time points (P<0.01). In the model group, the serum levels of TBIL, DBIL, TBA, ALT, and AST showed varying degrees of increase at 48 hours after establishment of model, compared with the values at 24 and 72 hours (P<0.05). At 24, 48, and 72 hours, the high-, medium-, and low-dose emodin groups had varying degrees of reductions in the serum levels of TBIL and TBA compared with the model group (P<0.05); the high- and low-dose emodin groups had significantly increased serum levels of TBA compared with the medium-dose emodin group (P<0.05). The model group had the most severe pathological changes at 48 hours. Compared with the model group, the high-, medium-, and low-dose emodin groups showed certain improvement in pathological changes of the liver at each time point, and the medium-dose emodin group had better improvement compared with the high- and low-dose emodin groups.</p><p><b>CONCLUSIONS</b>Emodin can effectively improve ANIT-induced intrahepatic cholestasis in young rats, and medium-dose emodin shows the best effect.</p>