Emodin ameliorates myocardial fibrosis in mice by inactivating the ROS/PI3K/Akt/mTOR axis

BACKGROUND

Emodin is a traditional medicine that has been shown to exert anti-inflammatory and anti-oxidative effects. Previous research has indicated that emodin can alleviate myocardial remodeling and inhibit myocardial hypertrophy and fibrosis. However, the mechanism by which emodin affects myocardial fibrosis (MF) has not yet been elucidated.

METHODS

Fibroblasts were treated with ANGII, and a mouse model of MF was established by ligation of the left anterior descending coronary artery. Cell proliferation was examined by a Cell Counting Kit-8 (CCK8) assay. Dihydroethidium (DHE) was used to measure reactive oxygen species (ROS) levels, and Masson and Sirius red staining were used to examine changes in collagen fiber levels. PI3K was over-expressed by lentiviral transfection to verify the effect of emodin on the PI3K/AKT/mTOR signaling axis. Changes in cardiac function in each group were examined by echocardiography.

RESULTS

Emodin significantly inhibited fibroblast proliferation, decreased intracellular ROS levels, significantly upregulated collagen II expression, downregulated α-SMA expression, and inhibited PI3K/AKT/mTOR pathway activation in vitro. Moreover, the in vivo results were consistent with the in vitro. Emodin significantly decreased ROS levels in heart tissue and reduced collagen fibrillogenesis. Emodin could regulate the activity of PI3K to increase the expression of collagen II and downregulate α-SMA expression in part through the PI3K/AKT/mTOR pathway, and emodin significantly improved cardiac structure and function in mice.

CONCLUSIONS

This study revealed that emodin targeted the PI3K/AKT/mTOR pathway to inhibit the development of myocardial fibrosis and may be an antifibrotic agent for the treatment of cardiac fibrosis.

On the antibacterial photodynamic inactivation mechanism of Emodin and Dermocybin natural photosensitizers: A theoretical investigation

A DFT and TDDFT study has been carried out on monomeric anthraquinones Emodin and Dermocybin (Em, Derm) recently proposed as natural antibacterial photosensitizers able to act also against gram-negative microbes. The computational study has been performed considering the relative amount of neutral and ionic forms of each compound in water, with the variation of pH. The occurrence of both Type I and Type II photoreactions has been explored computing the absorption properties of each species, the spin-orbit coupling constants (SOC), the vertical ionization potentials and the vertical electron affinities. The most plausible deactivation channels leading to the population of excited triplet states have been proposed. Our data indicate Emodin as more active than Dermocybin in antimicrobial photodynamic therapy throughout the Type II mechanism. Our data support a dual TypeI/II activity of the monomeric anthraquinones Emodin and Dermccybin in water, in all the considered protonation states.

New insights into the interaction of emodin with lipid membranes

Emodin is a natural anthraquinone derivative found in nature, widely known as an herbal medicine. Here, the partition, location, and interaction of emodin with lipid membranes of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) are experimentally investigated with different techniques. Our studies have considered the neutral form of emodin (EMH) and its anionic/deprotonated form (EM-), and their interaction with a more and less packed lipid membrane, DMPC at the gel and fluid phases, respectively. Though DSC results indicate that the two species, EMH and EM-, similarly disrupt the packing of DMPC bilayers, spin labels clearly show that EMH causes a stronger bilayer disruption, both in gel and fluid DMPC. Fluorescence spectroscopy shows that both EMH and EM- have a high affinity for DMPC: the binding of EM- to both gel and fluid DMPC bilayers was found to be quite similar, and similar to that of EMH to gel DMPC, Kp = (1.4 ± 0.3)x103. However, EMH was found to bind twice more strongly to fluid DMPC bilayers, Kp = (3.2 ± 0.3)x103. Spin labels and optical absorption spectroscopy indicate that emodin is located close to the lipid bilayer surface, and suggest that EM- is closer to the lipid/water interface than EMH, as expected. The present studies present a relevant contribution to the current understanding of the effect the two species of emodin, EMH and EM-, present on different microregions of an organism, as local pH values can vary significantly, can cause in a neutral lipid membrane, either more or less packed, liked gel and fluid DMPC, respectively, and could be extended to lipid domains of biological membranes.

Emodin activates autophagy to suppress oxidative stress and pyroptosis via mTOR-ULK1 signaling pathway and promotes multi-territory perforator flap survival

BACKGROUND

Multi-territory perforator flap reconstruction has been proven effective in treating large skin and soft tissue defects in clinical settings. However, in view of that the multi-territory perforator flap is prone to partial postoperative necrosis, increasing its survival is the key to the success of reconstruction. In this study, we aimed to clarify the effect of emodin on multi-territory perforator flap survival.

METHODS

Flap survival was assessed by viability area analysis, infrared laser imaging detector, HE staining, immunohistochemistry, and angiography. Western blotting, immunofluorescence assays, and real-time fluorescent quantitative PCR were performed to detect the indicators of oxidative stress, pyroptosis and autophagy.

RESULTS

After emodin treatment, the multi-territory perforator flap showed a significantly increased survival rate, which was shown to be closely related to the inhibition of oxidative stress and pyroptosis and enhanced autophagy. Meanwhile, the use of autophagy inhibitor 3 MA was found to reverse the inhibitory effects of emodin on oxidative stress and pyroptosis and weaken the improving effect of emodin on flap survival, suggesting that autophagy plays a critical role in emodin-treated flaps. Interestingly, our mechanistic investigations revealed that the positive effect of emodin on multi-territory perforator flap was attributed to the mTOR-ULK1 signaling pathway activation.

CONCLUSIONS

Emodin can inhibit oxidative stress and pyroptosis by activating autophagy via the mTOR-ULK1 pathway, thereby improving the multi-territory perforator flap survival.

ACSL4 promotes malignant progression of Hepatocellular carcinoma by targeting PAK2 transcription

Long-chain fatty acyl-Coa ligase 4 (ACSL4) is an important enzyme that converts fatty acids to fatty acyl-Coa esters, there is increasing evidence for its role in carcinogenesis. However, the precise role of ACLS4 in hepatocellular carcinoma (HCC) is not clearly understood. In the present study, we provide evidence that ACSL4 expression was specifically elevated in HCC and is associated with poor clinical outcomes. ACSL4 significantly promotes the growth and metastasis of HCC both in vitro and in vivo. RNA sequencing and functional experiments showed that the effect of ACSL4 on HCC development was heavily dependent on PAK2. ACSL4 expression is well correlated with PAK2 in HCC, and ACSL4 even transcriptionally increased PAK2 gene expression mediated by Sp1. In addition, emodin, a naturally occurring anthraquinone derivative, inhibited HCC cell growth and tumor progression by targeting ACSL4. In summary, ACSL4 plays a novel oncogene in HCC development by regulating PAK2 transcription. Targeting ACSL4 could be useful in drug development and therapy for HCC.

Protective effects of emodin on subchondral bone and articular cartilage in osteoporotic osteoarthritis rats: A preclinical study

BACKGROUND

Osteoporotic osteoarthritis (OP-OA) is a severe pathological form of OA, urgently requiring precise management strategies and more efficient interventions. Emodin (Emo), an effective ingredient found in the traditional Chinese medicine rhubarb, has been dEmonstrated to promote osteogenesis and inhibit extracellular matrix degradation. In this study, we aimed to investigate the interventional effects of Emo on the subchondral bone and cartilage of the knee joints in OP-OA model rats.

METHODS

Thirty-two SD rats were randomly and equally divided into sham, OP-OA, Emo low-dose, and Emo high-dose groups. Micro-CT scanning was conducted to examine the bone microstructure of the rat knee joints. H&E and Safranin O and Fast Green staining (SO&FG) were performed for the pathomorphological evaluation of the rat cartilage tissues. ELISA was used to estimate the rat serum expression levels of inflammatory factors, including interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α). Additionally, the CCK-8 assay was utilized for determining the viability of Emo-treated BMSCs. Western blot and real-time PCR analyses were also employed to measure the bone formation indexes and cartilage synthesis and decomposition indexes. Lastly, the osteogenic and chondrogenic differentiation efficiency of the BMSCs was investigated via Alizarin Red and Alcian Blue staining.

RESULTS

Emo intervention alleviated the bone microstructural disruption of the subchondral bone and articular cartilage in the OP-OA rats and up-regulated the expression of bone and cartilage anabolic metabolism indicators, decreased the expression of cartilage catabolism indicators, and diminished the expression of inflammatory factors in the rat serum (P<0.05). Furthermore, Emo reversed the decline in the osteogenic and chondrogenic differentiation ability of the BMSCs (P<0.05).

CONCLUSION

Emo intervention mitigates bone loss and cartilage damage in OP-OA rats and promotes the osteogenic and chondrogenic differentiation of BMSCs.

Biomimetic delivery of emodin via macrophage membrane-coated UiO-66-NH2 nanoparticles for acute pancreatitis treatment

Acute pancreatitis (AP) is a severe inflammatory condition with a rising incidence and high mortality rates, especially in severe cases. Emodin (ED), known for its potent anti-inflammatory properties, holds promise in addressing AP. However, its clinical application is hindered by limitations such as low bioavailability and insufficient target specificity. Herein, we developed a novel drug delivery system using macrophage membrane-coated UiO-66-NH2 nanoparticles loaded with ED (MVs-UiO-ED). UiO-66-NH2 was successfully synthesized and characterized, revealing an octahedral structure with a suitable size distribution. The successful loading of ED onto UiO-66-NH2 was confirmed by ultraviolet and infrared spectroscopy. Subsequently, MVs-UiO-ED was prepared by coating macrophage membrane-derived vesicles onto UiO-ED, resulting in a biomimetic delivery system. In vitro release studies demonstrated that MVs-UiO-ED exhibited a sustained-release profile, indicating its potential for prolonged drug circulation. An AP mouse model was established to evaluate the therapeutic efficacy of MVs-UiO-ED. Compared with the model group, MVs-UiO-ED significantly reduced serum levels of α-amylase and lipase, two indicators of pancreatitis severity. Furthermore, histopathological examinations revealed that MVs-UiO-ED ameliorated pancreatic tissue damage. This study underscores the potential of MVs-UiO-ED as an effective therapeutic approach for AP.

Antibacterial and antibiofilm potentials of Rumex dentatus root extract characterized by HPLC-ESI-Q-TOF-MS

The control of infections is one of the key strategies to treat cuts, wounds, lung, and skin infections. In this study the folkloric use of Rumex dentatus (R. dentatus) roots in the mentioned conditions was scientifically investigated. The methanolic (MeOH) crude extract of R. dentatus root was fractionated (n-hexane, ethyl acetate and water) via bioassay-guided method, and its antibacterial activity was evaluated using the agar well diffusion and Minimum inhibitory concentration (MIC) assays against clinical isolate of Pseudomonas aeruginosa (P. aeruginosa). The antibiofilm activity was measured using the crystal violet staining method. The crude extract, fractions and sub-fractions tested showed the MICs values ranging from 200 to 1000 μg/mL respectively. Among the fractions, notably, the water fraction exhibited the highest activity against P. aeruginosa. The water fraction was then subjected to thin layer chromatography (TLC). Following spectrometric analysis using HPLC-ESI-Q-TOF-MS, gallic acid and emodin were identified as the primary components within the same fraction, responsible for eliciting antibacterial and antibiofilm effects. The in-silico studies conducted with AutoDock Vina on the LasR protein, using both isolated gallic acid and emodin, confirm the binding affinity of these molecules to the active sites of the LasR protein that has regulatory role in building of biofilm formation and its pathogenicity. By scientifically validating the infection-controlling properties of R. dentatus, this research provides compelling evidence that supports its traditional use as reported in folklore. Moreover, this study contributes to our understanding of the plant's potential in managing infections, thereby substantiating its traditional therapeutic application in a scientific context.

Emodin ameliorates acute radiation proctitis in mice by regulating AKT/MAPK/NF-κB/VEGF pathways

BACKGROUND

Emodin, a natural anthraquinone derivative isolated from the roots of Rheum officinale Baill, has many pharmacological effects including anti-inflammatory, antioxidant, antiviral, antibacterial and anti-cancer. However, little is known about the effect of emodin on acute radiation proctitis (ARP). The present study was conducted to determine its effects and elucidate its mechanisms involving AKT/MAPK/NF-κB/VEGF pathways in ARP mice.

METHODS

Total 60 C57BL/6 mice were divided randomly into control group, ARP group, AKT inhibitor MK-2206 group, and different doses of emodin groups. ARP mice were induced by 27 Gy of 6 MV X-ray pelvic local irradiation. MK-2206 was given orally for 2 weeks on alternate days. Emodin was administered daily by oral gavage for 2 weeks. Subsequently, all mice were sacrificed on day 15. The rectal tissues were obtained for further tests. The general signs score and the pathological grade were used to evaluate the severity of ARP. The expression of NF-κB, VEGF and AQP1 were determined by immunohistochemistry and western blot. The expression of p-AKT, p-ERK, p-JNK, p-p38, Bcl-2 and Bax were assessed using western blot.

RESULTS

The worse general signs and damaged tissue structure of ARP mice were profoundly ameliorated by emodin. The expression of p-AKT, p-ERK, NF-κB, VEGF and AQP1 were significantly increased, resulting in the inflammation-induced angiogenesis in ARP mice. However, the expression of p-JNK and p-p38 were decreased, leading to the reduction of apoptosis in ARP mice. Excitedly, emodin reversed these changes, not only inhibited inflammation-induced angiogenesis, but also promoted apoptosis. Notably, the effects of emodin were similar to that of AKT inhibitor MK-2206, suggesting the involvement of AKT signaling in the effect of emodin.

CONCLUSION

These results suggest that emodin attenuates ARP in mice, and the underlying mechanism might involve inhibition of the AKT/ERK/NF-κB/VEGF pathways and the induction of apoptosis mediated by JNK and p38.

Synergistic dual cell therapy for atherosclerosis regression: ROS-responsive Bio-liposomes co-loaded with Geniposide and Emodin

The development of nanomaterials for delivering natural compounds has emerged as a promising approach for atherosclerosis therapy. However, premature drug release remains a challenge. Here, we present a ROS-responsive biomimetic nanocomplex co-loaded with Geniposide (GP) and Emodin (EM) in nanoliposome particles (LP NPs) for targeted atherosclerosis therapy. The nanocomplex, hybridized with the macrophage membrane (Møm), effectively evades immune system clearance and targets atherosclerotic plaques. A modified thioketal (TK) system responds to ROS-rich plaque regions, triggering controlled drug release. In vitro, the nanocomplex inhibits endothelial cell apoptosis and macrophage lipid accumulation, restores endothelial cell function, and promotes cholesterol effluxion. In vivo, it targets ROS-rich atherosclerotic plaques, reducing plaque area ROS levels and restoring endothelial cell function, consequently promoting cholesterol outflow. Our study demonstrates that ROS-responsive biomimetic nanocomplexes co-delivering GP and EM exert a synergistic effect against endothelial cell apoptosis and lipid deposition in macrophages, offering a promising dual-cell therapy modality for atherosclerosis regression.

The Role of Emodin in the Treatment of Bladder Cancer based on Network Pharmacology and Experimental Verification

BACKGROUND AND PURPOSE

Emodin, a compound derived from rhubarb and various traditional Chinese medicines, exhibits a range of pharmacological actions, including antiinflammatory, antiviral, and anticancer properties. Nevertheless, its pharmacological impact on bladder cancer (BLCA) and the underlying mechanism are still unclear. This research aimed to analyze the pharmacological mechanisms of Emodin against BLCA using network pharmacology analysis and experimental verification.

METHODS

Initially, network pharmacology was employed to identify core targets and associated pathways affected by Emodin in bladder cancer. Subsequently, the expression of key targets in normal bladder tissues and BLCA tissues was assessed by searching the GEPIA and HPA databases. The binding energy between Emodin and key targets was predicted using molecular docking. Furthermore, in vitro experiments were carried out to confirm the predictions made with network pharmacology.

RESULTS

Our analysis identified 148 common genes targeted by Emodin and BLCA, with the top ten target genes including TP53, HSP90AA1, EGFR, MYC, CASP3, CDK1, PTPN11, EGF, ESR1, and TNF. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses indicated a significant correlation between Emodin and the PI3KAKT pathway in the context of BLCA. Molecular docking investigations revealed a strong affinity between Emodin and critical target proteins. In vitro experiments demonstrated that Emodin inhibits T24 proliferation, migration, and invasion while inducing cell apoptosis. The findings also indicated that Emodin reduces both PI3K and AKT protein and mRNA expression, suggesting that Emodin may mitigate BLCA by modulating the PI3K-AKT signaling pathway.

CONCLUSION

This study integrates network pharmacology with in vitro experimentation to elucidate the potential mechanisms underlying the action of Emodin against BLCA. The results of this research enhance our understanding of the pharmacological mechanisms by which Emodin may be employed in treating BLCA.

The p53-mediated cell cycle regulation is a potential mechanism for emodin-suppressing osteosarcoma cells

Background

As the most common primary bone cancer, the therapy of osteosarcoma requires further study. An anthraquinone derivative, emodin, has been found to have anticancer potential. We proposed that emodin suppresses osteosarcoma by cell cycle regulation mediated by p53.

Methods

This study determined the effect of emodin on viability and apoptosis of 6 osteosarcoma cell lines (p53 null cells MG63, G292, and A-673; p53 mutated cells HOS and SK-PN-DW; p53 expressing cells U2OS and 2 osteoblast cell lines), then knockdown p53 in U2OS, and observed the impacts of emodin on p53, p21, cyclin proteins, and cell cycle.

Results

High dose emodin (40-160 μM) induced cell death and apoptosis of all the cell lines; medium dose emodin (20 μM) preferentially inhibited osteosarcoma cells; low dose emodin (1-10 μM) preferentially inhibited p53 expressing osteosarcoma cells. Emodin dose-dependently inhibited p53 and p21 in U2OS. Emodin at 10 μM decreased the expression of Cdk2, E2F, and Cdk1; and increased RB but had no effects on cyclin E and cyclin B. The knockdown of p53 almost eliminated all the impacts of 10 μM emodin on cell cycle proteins.

Conclusions

Emodin suppresses U2OS by p53-mediated cell cycle regulation.

Periodontal ligament stem cell-derived exosome-loaded Emodin mediated antimicrobial photodynamic therapy against cariogenic bacteria

BACKGROUND

This study was conducted to investigate the efficiency of periodontal ligament (PDL) stem cell-derived exosome-loaded Emodin (Emo@PDL-Exo) in antimicrobial photodynamic therapy (aPDT) on Streptococcus mutans and Lactobacillus acidophilus as the cariogenic bacteria.

MATERIALS AND METHODS

After isolating and characterizing PDL-Exo, the study proceeded to prepare and verify the presence of Emo@PDL-Exo. The antimicrobial effect, anti-biofilm activity, and anti-metabolic potency of Emo, PDL-Exo, and Emo@PDL-Exo were then evaluated with and without irradiation of blue laser at a wavelength of 405 ± 10 nm with an output intensity of 150 mW/cm2 for a duration of 60 s. In addition, the study assessed the binding affinity of Emodin with GtfB and SlpA proteins using in silico molecular docking. Eventually, the study examined the generation of endogenous reactive oxygen species (ROS) and changes in the gene expression levels of gelE and sprE.

RESULTS

The study found that using Emo@PDL-Exo-mediated aPDT resulted in a significant decrease in L. acidophilus and S. mutans by 4.90 ± 0.36 and 5.07 log10 CFU/mL, respectively (P < 0.05). The study found that using Emo@PDL-Exo for aPDT significantly reduced L. acidophilus and S. mutans biofilms by 44.7% and 50.4%, respectively, compared to untreated biofilms in the control group (P < 0.05). Additionally, the metabolic activity of L. acidophilus and S. mutans decreased by 58.3% and 71.2%, respectively (P < 0.05). The molecular docking analysis showed strong binding affinities of Emodin with SlpA and GtfB proteins, with docking scores of -7.4 and -8.2 kcal/mol, respectively. The study also found that the aPDT using Emo@PDL-Exo group resulted in the most significant reduction in gene expression of slpA and gtfB, with a decrease of 4.2- and 5.6-folds, respectively, compared to the control group (P < 0.05), likely due to the increased generation of endogenous ROS.

DISCUSSION

The study showed that aPDT using Emo@PDL-Exo can effectively reduce the cell viability, biofilm activity, and metabolic potency of S. mutans and L. acidophilus. aPDT also significantly reduced the expression levels of gtfB and slpA mRNA due to the increased endogenous ROS generation. The findings suggest that Emo@PDL-Exo-mediated aPDT could be a promising antimicrobial approach against cariogenic microorganisms.

In vitro effects of antimicrobial properties and shear bond strength of different concentrations of Emodin nanoparticles incorporated orthodontic composites

OBJECTIVE

Fixed appliances used in orthodontic treatment are accompanied by some drawbacks, including the development of white spots or enamel demineralization in the vicinity of the brackets and bonding failures. This study aims to evaluate the effect of combining different wt.% of Emodin nanoparticles (ENPs) with orthodontic adhesives to attain adhesives with improved antimicrobial and mechanical properties.

METHODS

ENPs were synthesized and added to orthodontic composite at different concentrations (0.5%, 1%, and 2%). The distribution of ENPs within the composite was evaluated using a field emission scanning electron microscope (FESEM). A total of 216 disks were prepared, with 144 subjected to an eluted components test, 36 used for disk agar diffusion (DAD) test, and 36 for biofilm inhibition test. These tests aimed to assess the antimicrobial activity of the composites against Streptococcus mutans, Lactobacillus acidophilus, and Candida albicans. Additionally, the bond strength between stainless-steel brackets and teeth was evaluated using the shear bond strength (SBS) test, and the adhesive remnant index (ARI) score was determined. One-way analysis of variance and Kruskal-Wallis test were used to analyse the SBS and ARI, respectively. For pairwise group comparison concerning the biofilm inhibition, DAD, and eluted components tests, the Tamhane and Games-Howell tests for data with unequal variances and the post-hoc Tukey's HSD and Scheffe tests for data with equal variances were used.

RESULTS

The FESEM results confirmed the synthesis and even distribution of ENPs in the composite. Only the 2% group showed significant biofilm inhibition against all microorganisms studied (P<0.05). The DAD test revealed that a 1% concentration of ENPs is sufficient to inhibit growth for all microorganisms. The eluted components test demonstrated that the 2% concentration of ENPs performed significantly better against S. mutans compared to the control group (P<0.05). The highest mean SBS was observed with the 0.5% ENP concentration, while no significant differences in SBS and ARI were found among the groups (P>0.05).

CONCLUSIONS

This in vitro study showed that the 2% concentration of ENP produced significantly improved antimicrobial activity without adversely affecting SBS and ARI score. This would support the addition of 2% ENP to orthodontic adhesives.

Emodin suppresses adipogenesis of bone marrow derived mesenchymal stem cells from aplastic anemia via increasing TRIB3 expression

BACKGROUND

Increasing evidence indicate that enhanced adipogenic differentiation of bone marrow mesenchymal stem cells (BM-MSCs) could contribute to the adiposity alteration in marrow microenvironment of aplastic anemia (AA). Identifying small molecule drugs with role in inhibiting adipogenesis of BM-MSCs may represent a novel direction in AA therapy by improving BM-MSCs mediated marrow microenvironment.

METHODS

For the purpose, we isolated AA BM-MSCs through whole bone marrow cell culture, evaluated a series of small molecule drugs using the in vitro adipogenic differentiation model of BM-MSCs, and finally focused on emodin, a natural anthraquinone derivative. Subsequently, we systematically investigated the molecular mechanism of emodin in attenuating adipogenic process by means of microarray profiling, bioinformatics analysis and lentivirus-mediated functional studies and rescue assay.

RESULTS

We found that emodin presented significantly suppressive effect on the in vitro adipogenic differentiation of AA BM-MSCs. Further mechanistic investigation revealed that emodin could increase the expression of Tribbles homolog 3 (TRIB3) which exhibited remarkably decreased expression in AA BM-MSCs compared with the normal counterparts and was subsequently demonstrated as a negative regulator in adipogenesis of AA BM-MSCs. Besides, TRIB3 depletion alleviated the suppressive effect of emodin on the adipogenic differentiation of AA BM-MSCs.

CONCLUSION

Our findings propose that emodin mediated TRIB3 up-regulation alleviates the adipogenic capacity of AA BM-MSCs, and emodin could serve as a potential therapeutic regimen for AA therapy.

Nano-emodin mediated photodynamic therapy for wound healing of donor site after free gingival graft: A parallel clinical trial

AIM

This study aimed to evaluate the effectiveness of nano-emodin (n-Emo) mediated photodynamic therapy (PDT) as an adjunctive therapy to conventional wound care in patients undergoing free gingival graft (FGG) treatment. The study employed a single-center, parallel, two-blind, randomized, controlled trial design.

METHOD AND MATERIAL

A total of 53 patients requiring FGG treatment were randomly assigned to one of three groups: the n-Emo mediated PDT group, the n-Emo gel group, and the control group. The n-Emo mediated PDT group received n-Emo gel on donor site followed by LED (450 nm, 1000 ± 1400 mW/cm2, 60-80 J/cm2, 60 s), the n-Emo gel group received only n-Emo gel on donor site, and the control group received a placebo gel on donor site. All groups received treatment immediately and 48 h after FGG surgery. Wound healing was assessed based on wound area, bleeding, color match, and epithelialization. Postoperative pain perception was evaluated using a Visual Analogue Scale (VAS), and the number of non-steroidal anti-inflammatory drug (NSAID) intakes was recorded.

RESULTS

The results showed that all groups demonstrated significant improvement in wound healing by day 28, with the n-Emo mediated PDT exhibiting significantly better healing on the 14th, 21st, and 28th day compared to the control group. Additionally, on the 28th day, the n-Emo mediated PDT showed significantly better healing than the n-Emo gel group. The n-Emo mediated PDT also had significantly lower pain scores than the control group. There were no significant differences in the number of NSAID intakes, bleeding, or color match among the groups, but all groups showed improved color match during follow-up. By the third week, all groups had fully epithelialized without significant differences, and no secondary bleeding incidents were reported.

CONCLUSION

The study concludes that n-Emo mediated PDT is an effective adjunctive therapy to conventional wound care for managing complication after surgery at donor site after FGG surgery.

Thermosensitive hydrogel with emodin-loaded triple-targeted nanoparticles for a rectal drug delivery system in the treatment of chronic non-bacterial prostatitis

BACKGROUND

The complex etiology and pathogenesis underlying Chronic Non-Bacterial Prostatitis (CNP), coupled with the existence of a Blood Prostate Barrier (BPB), contribute to a lack of specificity and poor penetration of most drugs. Emodin (EMO), a potential natural compound for CNP treatment, exhibits commendable anti-inflammatory, anti-oxidant, and anti-fibrosis properties but suffers from the same problems as other drugs.

METHODS

By exploiting the recognition properties of lactoferrin (LF) receptors that target intestinal epithelial cells (NCM-460) and prostate epithelial cells (RWPE-1), a pathway is established for the transrectal absorption of EMO to effectively reach the prostate. Additionally, hyaluronic acid (HA) is employed, recognizing CD44 receptors which target macrophages within the inflamed prostate. This interaction facilitates the intraprostatic delivery of EMO, leading to its pronounced anti-inflammatory effects. A thermosensitive hydrogel (CS-Gel) prepared from chitosan (CS) and β-glycerophosphate disodium salt (β-GP) was used for rectal drug delivery with strong adhesion to achieve effective drug retention and sustained slow release. Thus, we developed a triple-targeted nanoparticle (NPs)/thermosensitive hydrogel (Gel) rectal drug delivery system. In this process, LF, with its positive charge, was utilized to load EMO through dialysis, producing LF@EMO-NPs. Subsequently, HA was employed to encapsulate EMO-loaded LF nanoparticles via electrostatic adsorption, yielding HA/LF@EMO-NPs. Finally, HA/LF@EMO-NPs lyophilized powder was added to CS-Gel (HA/LF@EMO-NPs Gel).

RESULTS

Cellular assays indicated that NCM-460 and RWPE-1 cells showed high uptake of both LF@EMO-NPs and HA/LF@EMO-NPs, while Raw 264.7 cells exhibited substantial uptake of HA/LF@EMO-NPs. For LPS-induced Raw 264.7 cells, HA/LF@EMO-NPs can reduce the inflammatory responses by modulating TLR4/NF-κB signaling pathways. Tissue imaging corroborated the capacity of HA/LF-modified formulations to breach the BPB, accumulating within the gland's lumen. Animal experiments showed that rectal administration of HA/LF@EMO-NPs Gel significantly reduced inflammatory cytokine expression, oxidative stress levels and fibrosis in the CNP rats, in addition to exerting anti-inflammatory effects by inhibiting the NF-κB signaling pathway without obvious toxicity.

CONCLUSION

This triple-targeted NPs/Gel rectal delivery system with slow-release anti-inflammatory, anti-oxidant, and anti-fibrosis properties shows great potential for the effective treatment of CNP.

Comparative pharmacokinetics and tissue distribution of polydatin, resveratrol, and emodin after oral administration of Huzhang and Huzhang-Guizhi herb-pair extracts to rats

ETHNOPHARMACOLOGICAL RELEVANCE

Huzhang-Guizhi herb pair (HGHP), composed of Polygonum cuspidatum (Huzhang [HZ] in Chinese, the root of Polygonum cuspidatum Sieb. & Zucc.) and Ramulus Cinnamomi (Guizhi [GZ] in Chinese, the dried twig of Cinnamomum cassia Presl.), is a popular herb pair commonly used to treat arthritis and involved in many Chinese prescriptions. In order to reveal the influence of GZ on HZ on bioavailability, the pharmacokinetic behaviors and tissue distribution variations of the three analytes from HZ were detected between oral administration of HZ and HGHP extracts to rats.

MATERIALS AND METHODS

Male Sprague-Dawley rats were randomly assigned to two groups for pharmacokinetics study and eight groups for tissues distribution research with the equivalent dose of 18 g crude HZ/kg. Assays for analytes from HZ (polydatin, resveratrol, emodin) were developed and validated using high performance liquid chromatography with ultraviolet detection (HPLC-UV).

RESULTS

Part pharmacokinetic parameters including area under the concentration-time curve (AUC), the maximum plasma concentration (Cmax), biological half-life (t1/2), mean residence time (MRT), time to peak concentration (Tmax), clearance rate/bioavailability (CL/F) and volume of distribution/bioavailability (Vd/F) showed significant difference (P < 0.05) after oral administration of HGHP, as compared to those of HZ. The three analytes could be detected in heart, liver, spleen, lung, kidney and brain. Compared with the HZ group, AUC0-t of polydatin in heart, liver and kidney increased significantly (p < 0.05) while that in spleen decreased significantly (p < 0.05); AUC0-t of resveratrol in all detected tissues increased conspicuously (p < 0.05) in the HGHP group; AUC0-t of emodin in heart, liver, spleen, lung, and kidney increased conspicuously (p < 0.05), and decreased obviously (p < 0.05) in brain in the HGHP group.

CONCLUSIONS

GZ could strongly influence the pharmacokinetic parameters and tissue distribution characteristics of polydatin, resveratrol and emodin in rats when administrated with HZ or HGHP extracts. It might provide a reference for further explanation of the compatibility mechanism and the clinical application of HGHP.

Ultrasound-assisted extraction of emodin from Rheum officinale Baill and its antibacterial mechanism against Streptococcus suis based on CcpA

Emodin was extracted from Rheum officinale Baill by ultrasound-assisted extraction (UAE), and ethanol was chosen as the suitable solvent through SEM and molecular dynamic simulation. Under the optimum conditions (power 541 W, time 23 min, liquid to material ratio 13:1 mL/g, ethanol concentration 83 %) predicted by RSM, the yield of emodin was 2.18 ± 0.11 mg/g. Moreover, ultrasound power and time displayed the significant effects on the extraction process. Extracting dynamics analysis indicated that the extraction process of emodin by UAE conformed to Fick's second diffusion law. The results of antibacterial experiments suggested that emodin can damage cell membrane and inhibit the expression of cps2A, sao, mrp, epf, neu and the hemolytic activity of S. suis. Biolayer interferometry and FT-IR multi-peak fitting assays demonstrated that emodin induced a secondary conformational shift in CcpA. Molecular docking and molecular dynamics confirmed that emodin bound to CcpA through hydrogen bonding (ALA248, GLU249, GLY129 and ASN196) and π-π T-shaped interaction (TYR225 and TYR130), and the mutation of amino acid residues affected the affinity of CcpA to emodin. Therefore, emodin inhibited the sugar utilization of S. suis through binding to CcpA, and CcpA may be a potential target to inhibit the growth of S. suis.

The effect of different concentration of emodin nanoparticles, as an antibacterial agent, on the flexural resistance of acrylic resin used in orthodontics: An in vitro study

OBJECTIVE

The aim of this study was to investigate the impact of emodin nanoparticles (n-Emo) on the flexural strength of acrylic resin used in orthodontics.

METHODS

A total of 24 acrylic resin discs were prepared according to ISO:20795-1 and divided into four groups (n=6): 0% n-Emo, 0.5% n-Emo, 1% n-Emo, and 2% n-Emo. The flexural strength of each group was measured using the Universal Testing Machine. One-way analysis of variance (ANOVA) and Tukey tests were used to analyse the data.

RESULTS

The highest flexural strength values were observed in the groups containing 0% and 0.5% concentrations of n-Emo, while the lowest mean flexural strength was recorded in the group containing 2% concentration of n-Emo. There were significant difference in flexural strength values between the groups containing 0% with those containing 1% and 2% concentrations (P=0.045, P=0.011, respectively), as well as between those containing 0.5% and 2% concentrations of n-Emo (P=0.041).

CONCLUSIONS

The results of the study showed that the incorporation of n-Emo had a negative impact on the flexural strength of the acrylic resin utilized in orthodontics. Nonetheless, the mean flexural strength values of all groups fell within the normal range, implying that the addition of n-Emo did not jeopardize the mechanical properties of the acrylic resin. It is therefore conceivable that the use of n-Emo as an antimicrobial agent in acrylic resin could be a promising approach to reducing enamel demineralisation and dental caries, while preserving its mechanical properties. This study was approved by the ethics committee of the Tehran University of Medical Sciences (1401-2-398-54892).

Integration of microbiota and metabolomics reveals the analgesic mechanisms of emodin against neuropathic pain

BACKGROUND AND OBJECTIVE

Neuropathic pain (NeP) induced dysbiosis of intestinal microbiota in chronic constriction injury (CCI) rats. Emodin has analgesic effect but the detailed mechanism is not clear at the present time. This study aims to explore the underling mechanism of action of emodin against NeP with in CCI model.

METHODS

Male SD rats (180-220 g) were randomly divided into three groups: sham group, CCI group, and emodin group. Behavioral tests were performed to evaluate the therapeutic effects of emodin on CCI model. Feces and spinal cords of all rats were collected 15 days after surgery. 16S rDNA sequencing, untargeted metabolomics, qPCR and ELISA were performed.

RESULTS

Mechanical withdrawal thresholds (MWT), thermal withdrawal latency (TWL) and Sciatic functional index (SFI) in emodin group were significantly higher than CCI group (P < 0.05). Emodin not only inhibited the expression of pro-inflammatory cytokines in the spinal cords and colonic tissue, but also increased the expression of tight junction protein in colonic tissue. 16S rDNA sequencing showed that emodin treatment changed the community structure of intestinal microbiota in CCI rats. Untargeted metabolomics analysis showed that 33 differential metabolites were screened out between CCI group and emodin group. After verification, we found that emodin increased the level of S-adenosylmethionine (SAM) and Histamine in the spinal cord of CCI rats.

CONCLUSION

Emodin was effective in relieving neuropathic pain, which is linked to inhibition inflammatory response, increasing the proportion of beneficial bacteria and beneficial metabolites.

Emodin attenuates cardiomyocyte pyroptosis in doxorubicin-induced cardiotoxicity by directly binding to GSDMD

BACKGROUND

Doxorubicin (Dox), which is an anticancer drug, has significant cardiac toxicity and side effects. Pyroptosis occurs during Dox-induced cardiotoxicity (DIC), and drug inhibition of this process is one therapeutic approach for treating DIC. Previous studies have indicated that emodin can reduce pyroptosis. However, the role of emodin in DIC and its molecular targets remain unknown.

HYPOTHESIS/PURPOSE

We aimed to clarify the protective role of emodin in mitigating DIC, as well as the mechanisms underlying this effect.

METHODS

The model of DIC was established via the intraperitoneal administration of Dox at a dosage of 5 mg/kg per week for a span of 4 weeks. Emodin at two different doses (10 and 20 mg/kg) or a vehicle was intragastrically administered to the mice once per day throughout the Dox treatment period. Cardiac function, myocardial injury markers, pathological morphology of the heart, level of pyroptosis and mitochondrial function were assessed. Protein microarray, biolayer interferometry and pull-down assays were used to confirm the target of emodin. Moreover, GSDMD-overexpressing plasmids were transfected into GSDMD-/- mice and HL-1 cells to further verify whether emodin suppressed GSDMD activation.

RESULTS

Emodin therapy markedly enhanced cardiac function and reduced cardiomyocyte pyroptosis in mice induced by Dox. Mechanistically, emodin binds to GSDMD and inhibits the activation of GSDMD by targeting the Trp415 and Leu290 residues. Moreover, emodin was able to mitigate Dox-induced cardiac dysfunction and myocardial injury in GSDMD-/- mice overexpressing GSDMD, as shown by increased EF and FS, decreased serum levels of CK-MB, LDH and IL-1β and mitigated cell death and cell morphological disorder. Additionally, emodin treatment significantly reduced GSDMD-N expression and plasma membrane disruption in HL-1 cells overexpressing GSDMD induced by Dox. In addition, emodin reduced mitochondrial damage by alleviating Dox-induced GSDMD perforation in the mitochondrial membrane.

CONCLUSION

Emodin has the potential to attenuate DIC by directly binding to GSDMD to inhibit pyroptosis. Emodin may become a promising drug for prevention and treatment of DIC.

ROS/pH dual-sensitive emodin-chlorambucil co-loaded micelles enhance anti-tumor effect through combining oxidative damage and chemotherapy

The high level of reactive oxygen species (ROS) at the tumor site has been widely used in the tumor targeted delivery. However, the ROS stimulus-responsive vector itself is also a ROS consumer, and the consumption of endogenous ROS may not be sufficient to maintain sustained drug release. In this study, we designed and synthesized ROS/pH dual-sensitive polymer micelles for the co-delivery of emodin (EMD) and chlorambucil (CLB). The release of quinone methides (QM) can consume glutathione (GSH), on the one hand, it can enhance the chemotoxicity of phenylbutyrate nitrogen mustard, on the other hand, emodin can induce oxidative damage of tumor cells and maintain the sustained targeted release of drugs.

Emodin ameliorates matrix degradation and apoptosis in nucleus pulposus cells and attenuates intervertebral disc degeneration through LRP1 in vitro and in vivo

Low back pain (LBP) is the leading cause of disability worldwide, with a strong correlation to intervertebral disc degeneration (IDD). Inflammation-induced extracellular matrix (ECM) degradation plays a major role in IDD's progression. Emodin, known for its anti-inflammatory effects and ability to inhibit ECM degradation in osteoarthritis, but its role in IDD is unclear. Our study aimed to explore emodin's role and mechanisms on IDD both in vivo and in vitro. We discovered that emodin positively regulated anabolic markers (COL2A1, aggrecan) and negatively impacted catabolic markers (MMP3, MMP13) in nucleus pulposus cells, while also inhibiting cell apoptosis under inflammation environment. We revealed that emodin inhibits inflammation-induced NF-ĸB activation by suppressing the degradation of LRP1 via the proteasome pathway. Additionally, LRP1 was validated as essential to emodin's regulation of ECM metabolism and apoptosis, both in vitro and in vivo. Ultimately, we demonstrated that emodin effectively alleviates IDD in a rat model. Our findings uncover the novel pathway of emodin inhibiting ECM degradation and apoptosis through the inhibition of NF-κB via LRP1, thus alleviating IDD. This study not only broadens our understanding of emodin's role and mechanism in IDD treatment but also guides future therapeutic interventions.

Histological Effect of Emodin on Acute Vocal Fold Injury in a Rat Model

OBJECTIVES

Emodin has beneficial effects on wound healing and reduces excessive fibrosis during tissue regeneration. Its positive effects on the wound-healing process were demonstrated on human fibroblasts. The aim of the present study was to evaluate the effectiveness of emodin application on acute vocal fold injury.

MATERIALS AND METHODS

Twenty-four Wistar albino rats were divided into three groups: control, sham, and emodin group. The glottis was examined using a 30°-2.7 mm diameter telescope, and vocal folds was unilaterally wounded by a microscissor through the entire layer of the lamina propria down to the vocalis muscle. While no procedure(no acute injury of the vocal fold or an injection of saline/emodin) was applied to the control group, 0.5 cc of saline was injected into the sham group and 0.5 cc of emodin in the emodin group, just lateral to the vocal folds, with 27 gauge injectors. Animals were sacrificed on the 21st day after the procedure. After excised larynx experiments, serial sections were prepared from the vocal fold. Hematoxylin eosin and immunohistochemical staining were performed and fibroblast density, lamina propria thickness, and vessel formation were graded from 0 (none) to 3 (severe reaction). Transforming growth factor-beta 1 (TGF-β1) and matrix metalloproteinase-9 (MMP-9) staining was used for immunohistochemical examinations. Four-point scoring scale for intensity being scored as 0 (no staining) to 3 (severeley stained) to quantify immonuhistochemical reaction. This scoring system was applied to vocal fold epithelium, lamina propria, vessel wall, and vocalis muscle tissues. The groups were compared with the Kruskal Wallis and Dunn tests.

RESULTS

Histologically, there was no significant difference (P > 0.05) between the sham group and the emodin group in terms of fibroblast density, vessel formation, and lamina propria thickness. These parameters were higher (P < 0.05) in both groups compared to the control group. In the lamina propria and vessel wall, MMP-9 staining was more intense in the emodin group than in the sham group. TGF-β1 staining of lamina propria, epithelial tissue, and vocalis muscle was significantly more intense in the emodin group than in the other groups.

CONCLUSION

Emodin induced MMP-9 and TGF-1 staining in the vocalis muscle and epithelium, as well as TGF-1 staining in the lamina propria. In terms of fibroblast density, new vascular creation, and LP thickness in acute vocal fold damage, there was no difference between saline administration and emodin injection. It may increase fibroblast activation in the acute phase of wound healing, but its long-term effects should be further investigated.

Research Progress and New Perspectives of Anticancer Effects of Emodin

Emodin is a natural compound found in several traditional Chinese medicines, including Rheum palmatum and Polygonum cuspidatum. Recent studies have shown that emodin exhibits potent anticancer effects against a variety of cancer types, including liver, breast, lung, and colon cancer. Emodin's anticancer effects are mediated through several mechanisms, including inhibition of cell proliferation, induction of apoptosis, and suppression of tumor angiogenesis and metastasis. In this review, we provide an overview of recent research progress and new perspectives on emodin's anticancer effect. We summarize the current understanding of the molecular mechanisms underlying emodin's anticancer activity, including its effects on signaling pathways such as the PI3K/Akt, MAPK, and NF-[Formula: see text]B pathways. We also discuss the potential of emodin as a therapeutic agent for cancer treatment, including its use in combination with conventional chemotherapeutic drugs and as a sensitizer for radiotherapy. Furthermore, we highlight recent advances in the development of emodin derivatives and their potential as novel anticancer agents. Finally, we discuss the challenges and opportunities for the translation of emodin's anticancer properties into clinical applications, including the need for further preclinical and clinical studies to evaluate its safety and efficacy. In conclusion, emodin represents a promising natural compound with potent anticancer properties, and its potential as a therapeutic agent for cancer treatment warrants further investigation. This review provides a comprehensive overview of the current research progress and new perspectives on emodin's anticancer effects, which may facilitate the development of novel therapeutic strategies for cancer treatment.

Emodin Inhibits the Indoxyl Sulfate-Induced trans-Differentiation of Vascular Smooth Muscle Cells through Upregulating Thrombospondin-1

BACKGROUND

Indoxyl sulfate (IS) is a protein-bound uremic toxin with vascular toxicity. The primary cause of death in uremic patients on maintenance hemodialysis is vascular disease, and it had been reported that vascular smooth muscle cells (VSMCs) trans-differentiation (VT) plays a vital role in the context of vascular diseases, but the underlying mechanisms remain obscure. Thrombospondin-1 (TSP-1) participates in vascular calcification by keeping the balance of extracellular matrix, but its role in IS-induced VT is unclear.

METHODS

In this study, clinical specimens, animal models, and in vitro VSMCs were used to investigate the role of TSP-1 in IS induced VT and the potential therapeutic methods.

RESULTS

We found that TSP-1 was significantly decreased in arterial samples from uremic patients, animal models, and in VSMCs after IS treatment. Downregulation of TSP-1 sufficiently induced the trans-differentiation genotypes of VSMCs.

CONCLUSION

Emodin, the main monomer extracted from rhubarb, could alleviate IS-induced VT in vitro by upregulating TSP-1. Taken together, IS induces VT by downregulating TSP-1. Emodin might be a candidate drug to alleviate VT under IS treatment.

Systems biology based miRNA-mRNA expression pattern analysis of Emodin in breast cancer cell lines

Breast cancer has been among the most prominent cancers with high mortality. Currently most of the offered therapeutics are toxic; hence, less toxic therapeutic intervention is required. Here, we studied the molecular mechanisms of the effect of a phytoestrogen Emodin on estrogen receptor positive MCF-7 and negative MDA-MB-231 cells by carrying out a comprehensive network assessment. Differentially expressed microRNAs along with their previously identified differentially expressed mRNAs were analyzed through microarrays by using integrative systems biology approach. For each cell line miRNA-target gene networks were built, gene ontology and pathway enrichment analyses were performed, enrichment maps were constructed and the potential key genes, miRNAs and miRNA-gene interactions were studied.

Emodin and rhapontigenin inhibit the replication of African swine fever virus by interfering with virus entry

Africa swine fever (ASF) is a highly pathogenic contagion caused by African swine fever virus (ASFV), which not only affects the development of domestic pig industry, but also causes huge losses to the world agricultural economy. Vaccine development targeting ASFV remains elusive, which leads to severe difficulties in disease prevention and control. Emodin (EM) and rhapontigenin (RHAG), which are extracted from the dried rhizome of Polygonum knotweed, have various biological properties such as anti-neoplastic and anti-bacterial activities, but no studies have reported that they have anti-ASFV effects. This study discovered that EM and RHAG at different concentrations had a significant dose-dependent inhibitory effect on the ASFV GZ201801 strain in porcine alveolar macrophages (PAMs), and at the specified concentration, EM and RHAG showed continuous inhibition at 24 h, 48 h and 72 h. Not only did they strongly impact virion attachment and internalization, but also inhibit the early stages of ASFV replication. Further research proved that the expression level of Rab 7 protein was reduced by EM and RHAG, and treatments with EM and RHAG induced the accumulation of free cholesterol in endosomes and inhibited endosomal acidification, which prevented the virus from escaping and shelling from late endosomes. This study summarized the application of EM and RHAG in inhibiting ASFV replication in-vitro. Similarly, EM and RHAG targeted Rab 7 in the viral endocytosis pathway, inhibited viral infection, and induced the accumulation of cholesterol in the endosomes and the acidification of the endosomes to inhibit uncoating. A reference could be made to the results of this study when developing antiviral drugs and vaccines.

Dietary emodin alleviates lipopolysaccharide-induced intestinal mucosal barrier injury by regulating gut microbiota in piglets

This study was to determine the effects of dietary emodin (ED) on the intestinal mucosal barrier, nuclear factor kappa-B (NF-κB) pathways, and gut microbial flora in lipopolysaccharide (LPS)-induced piglets. Twenty-four weaned piglets were chosen and 4 treatments were created by randomly distributing piglets into CON, ED, LPS, and ED_LPS groups. Experiments were done in a 2 × 2 factorial arrangement and maintained for 21 d. Dietary treatment (a basal diet or 300 mg/kg ED) and immunological challenge (LPS or sterile saline) were 2 major factors. Intraperitoneal injections of LPS or sterilized saline were given to piglets on d 21. Six hours after the LPS challenge, all piglets were euthanized for sample collection and analysis. The results showed that piglets of the ED_LPS group had higher (P < 0.05) villus height to crypt depth ratio (VCR), and lower (P < 0.05) plasma D-lactate and diamine oxidase (DAO) than the LPS group. Furthermore, ED inhibited (P < 0.05) the decrease of glutathione peroxidase (GSH-Px) and catalase (CAT) activities and increase of malonaldehyde level (P < 0.05) in jejunal mucosa induced by LPS. The mRNA levels of pro-inflammatory cytokine genes (IL-6, IL-1β, and TNF-α) were significantly reduced (P < 0.05), and the mRNA levels of antioxidant enzyme genes (GPX-1, SOD2 and CAT), as well as protein and mRNA levels of tight junction proteins (occludin, claudin-1, and ZO-1), were also significantly increased (P < 0.05) by ED addition in LPS-induced piglets. Meanwhile, ED supplementation significantly decreased the LPS-induced protein levels of cyclooxygenase-2 and phosphorylation levels of NF-κB p65 and IκBα in jejunal mucosa. Emodin had a significant effect on the composition of gut microbial flora at various taxonomic positions as indicated by 16S RNA sequencing. The acetic acid, isobutyric acid, valeric acid, and isovaleric acid concentrations in the cecum were also increased by ED addition in pigs (P < 0.05). Furthermore, the correlation analysis revealed that some intestinal microbiota had a potential relationship with jejunal VCR, plasma D-lactate and DAO, jejunal mucosa GSH-Px and CAT activity, and cecal short-chain fatty acid concentration. These data suggest that ED is effective in alleviating LPS-induced intestinal mucosal barrier injury by modulating gut microbiota in piglets.

Oral hydrogel nanoemulsion co-delivery system treats inflammatory bowel disease via anti-inflammatory and promoting intestinal mucosa repair

BACKGROUND

Due to oral nano-delivery systems for the treatment of inflammatory bowel disease (IBD) are often failed to accumulated to the colonic site and could not achieve controlled drug release, it's urgent to develop a microenvironment responsive drug delivery to improve therapy efficacy. Inflammation at the IBD site is mainly mediated by macrophages, which are the key effector cells. Excessive inflammation leads to oxidative stress and intestinal mucosal damage. The use of curcumin (CUR) and emodin (EMO) together for the treatment of IBD is promising due to their respective anti-inflammatory and intestinal mucosal repair effects. In view of the pH gradient environment of gastrointestinal tract, here we prepared pH-responsive sodium alginate (SA) hydrogel-coated nanoemulsions to co-deliver CUR and EMO (CUR/EMO NE@SA) to achieve controlled drug release and specifically target macrophages of the colon.

RESULTS

In this study, a pH-responsive CUR/EMO NE@SA was successfully developed, in which the CUR/EMO NE was loaded by chitosan and further crosslinked with sodium alginate. CUR/EMO NE@SA had a pH-responsive property and could achieve controlled drug release in the colon. The preparation could significantly alleviate and improve the colon inflammatory microenvironment by decreasing TNF-α and IL-6 expression, increasing IL-10 expression, scavenging reactive oxygen species in macrophages, and by ameliorating the restoration of intestinal mucosal tight junction protein expression. Furthermore, we revealed the molecular mechanism of the preparation for IBD treatment, which might due to the CUR and EMO synergic inhibition of NF-κB to improve the pro-inflammatory microenvironment. Our study provides a new IBD therapy strategy via synergically inhibiting inflammatory, repairing mucosal and clearing ROS by pH-sensitive hydrogel-encapsulated nanoemulsion drug delivery system, which might be developed for other chronic inflammatory disease treatment.

CONCLUSIONS

It's suggested that pH-sensitive hydrogel-coated nanoemulsion-based codelivery systems are a promising combinatorial platform in IBD.

Chitosan-based double network hydrogel loading herbal small molecule for accelerating wound healing

Skin injuries are one of the most common clinical traumas worldwide, and wound dressings are considered to be one of key factors in wound healing. Natural polymer-based hydrogels have been developed as ideal materials for a new generation of dressings due to their excellent biocompatibility and wetting ability. However, the inadequate mechanical performances and lack of efficacy in promoting wound healing have limited the application of natural polymer-based hydrogels as wound dressings. In this work, a double network hydrogel based on natural chitosan molecules was constructed to enhance the mechanical properties, and emodin, a herbal natural product, was loaded into the hydrogel to improve the healing effect of the dressing. The structure of the chitosan-emodin network formed by Schiff base reaction and microcrystalline network of biocompatible polyvinyl alcohol endowed hydrogels with excellent mechanical properties and ensured its integrity as wound dressings. Moreover, the hydrogel showed excellent wound healing properties due to the loading of emodin. The hydrogel dressing could promote cell proliferation, cell migration, and secretion of growth factors. The animal experimental results also demonstrated that the hydrogel dressing facilitated the regeneration of blood vessels and collagen and accelerated wound healing.

Emodin-Based Nanoarchitectonics with Giant Two-Photon Absorption for Enhanced Photodynamic Therapy

Two-photon-excited photodynamic therapy (TPE-PDT) has significant advantages over conventional photodynamic therapy (PDT). However, obtaining easily accessible TPE photosensitizers (PSs) with high efficiency remains a challenge. Herein, we demonstrate that emodin (Emo), a natural anthraquinone (NA) derivative, is a promising TPE PS with a large two-photon absorption cross-section (TPAC: 380.9 GM) and high singlet oxygen (1 O2 ) quantum yield (31.9 %). When co-assembled with human serum albumin (HSA), the formed Emo/HSA nanoparticles (E/H NPs) possess a giant TPAC (4.02×107  GM) and desirable 1 O2 generation capability, thus showing outstanding TPE-PDT properties against cancer cells. In vivo experiments reveal that E/H NPs exhibit improved retention time in tumors and can ablate tumors at an ultra-low dosage (0.2 mg/kg) under an 800 nm femtosecond pulsed laser irradiation. This work is beneficial for the use of natural extracts NAs for high-efficiency TPE-PDT.

A mannitol-modified emodin nano-drug restores the intestinal barrier function and alleviates inflammation in a mouse model of DSS-induced ulcerative colitis

BACKGROUND

Ulcerative colitis (UC) is an inflammatory disease of the colon that is characterized by mucosal ulcers. Given its increasing prevalence worldwide, it is imperative to develop safe and effective drugs for treating UC. Emodin, a natural anthraquinone derivative present in various medicinal herbs, has demonstrated therapeutic effects against UC. However, low bioavailability due to poor water solubility limits its clinical applications.

METHODS

Emodin-borate nanoparticles (EmB) were synthesized to improve drug solubility, and they modified with oligomeric mannitol into microgels (EmB-MO) for targeted delivery to intestinal macrophages that express mannose receptors. UC was induced in a mouse model using dextran sulfate sodium (DSS), and different drug formulations were administered to the mice via drinking water. The levels of inflammation-related factors in the colon tissues and fecal matter were measured using enzyme-linked immunosorbent assay. Intestinal permeability was evaluated using fluorescein isothiocyanate dextran. HE staining, in vivo imaging, real-time PCR, and western blotting were performed to assess intestinal barrier dysfunction.

RESULTS

Both EmB and EmB-MO markedly alleviated the symptoms of UC, including body weight loss, stool inconsistency, and bloody stools and restored the levels of pro- and anti-inflammatory cytokines. However, the therapeutic effects of EmB-MO on the macroscopic and immunological indices were stronger than those of EmB and similar to those of 5-aminosalicylic acid. Furthermore, EmB-MO selectively accumulated in the inflamed colon epithelium and restored the levels of the gut barrier proteins such as ZO-1 and Occludin.

CONCLUSIONS

EmB-MO encapsulation significantly improved water solubility, which translated to greater therapeutic effects on the immune balance and gut barrier function in mice with DSS-induced UC. Our findings provide novel insights into developing emodin-derived drugs for the management of UC.

Emodin and aloe-emodin, two potential molecules in regulating cell migration of skin cells through the MAP kinase pathway and affecting Caenorhabditis elegans thermotolerance

BACKGROUND

Emodin and aloe-emodin are two anthraquinones having positive effects in wound healing. However, their mechanism of action of wound healing is not fully understood. The MAP kinase family, which plays an active role in wound healing, is a well-characterized large family of serine/threonine kinases and regulates processes such as proliferation, oncogenesis, differentiation, and inflammation in the cell. The aim of this study is to comparatively elucidate the mechanisms of action of emodin and aloe-emodin, which are potential agents in wound healing.

METHODS

The mechanism of the effects of emodin and aloe-emodin on cell viability and cell migration was examined using the human skin fibroblast (CCD-1079Sk) cell line. The gene expression levels of the MAP kinases (JNK, P38, ERK) in the skin fibroblast cells along with a molecular docking study analyzing their interaction potential were evaluated. Furthermore, the molecules' effects on the lifespan of Caenorhabditis elegans were studied.

RESULTS

Emodin and aloe-emodin inhibited the ATP content of the cells in a concentration dependent manner and accelerated cell migration at the lower concentrations while inhibiting cell migration in the higher concentration treatment groups. The expressions of JNK and P38 were upregulated at the low concentrations and downregulated at the higher concentrations. The molecular docking studies of the molecules gave high docking scores indicating their interaction potential with JNK and P38. C. elegans lifespan under heat stress was observed longer after 75 µM emodin and was significantly reduced after 150 µM aloe-emodin treatment.

CONCLUSION

Aloe-emodin was found to be more potent on cell viability, cell migration, gene expression levels of the MAP kinases in healthy fibroblastic skin cells, and on the lifespan of C. elegans. This study reveals the functional effects and the biological factors that interact in the wound healing process of emodin and aloe-emodin, and give a possible treatment alternative to shorten the duration of wound care.

Emodin attenuates high lipid-induced liver metastasis through the AKT and ERK pathways in vitro in breast cancer cells and in a mouse xenograft model

Emodin, a natural anthraquinone derivative, can inhibit lipid synthesis and breast cancer cell proliferation. We previously found that emodin decreased breast cancer liver metastasis via epithelial-to-mesenchymal transition (EMT) inhibition. However, the mechanism through which emodin affects breast cancer liver metastasis in high-fat diet-induced obese and hyperlipidemic mice has not been elucidated. Bioinformatics analysis was used to reveal the potential targets and pathways of emodin. The mouse model of liver metastasis was established by injecting breast cancer cells into the left ventricle in high-fat diet-induced obese mice. The effect of emodin on inhibiting liver metastasis of breast cancer was evaluated by animal experiments. The mechanisms through which emodin inhibits liver metastasis of breast cancer were studied by cell and molecular biological methods. Emodin reduced lipid synthesis by inhibiting the expression of triglyceride (TG) synthesis-related genes, such as fatty acid synthase (Fasn), glycerol-3-phosphate acyltransferase 1 (Gpat1), and stearoyl-CoA desaturase (Scd1), and ultimately reduced liver metastasis in breast cancer. In addition, emodin inhibited breast cancer cell proliferation and invasion through the serine/threonine kinase (AKT) signaling and extracellular-regulated protein kinase (ERK) pathways by interacting with CSNK2A1, ESR1, ESR2, PIM1 and PTP4A3. Our results indicate that emodin may have therapeutic potential in the prevention or treatment of breast cancer liver metastasis.

The elucidation of the anti-inflammatory mechanism of EMO in rheumatoid arthritis through an integrative approach combining bioinformatics and experimental verification

Introduction: Emodin (EMO), a natural derivative of the anthraquinone family mainly extracted from rhubarb (Rheum palmatum), has previously been demonstrated to possess superior anti-inflammatory properties from a single target or pathway. In order to explore the underlying mechanism of action of EMO against rheumatoid arthritis (RA), a network pharmacology approach was employed. Methods: A gene expression profile from GSE55457 available from the Gene Expression Omnibus (GEO) database was used to identify the targets of EMO action. Further, single cell RNA sequencing data from GEO database of RA patients (GSE159117) were downloaded and analysed. To further investigate the anti-RA effect of EMO on MH7A cells, the expression of IL-6 and IL-1β were monitored. Finally, RNA-seq analyses were conducted on synovial fibroblasts from EMO-treated. Result: We screened the key targets of EMO against RA using network pharmacology methods, including HMGB1, STAT1, EGR1, NR3C1, EGFR, MAPK14, CASP3, CASP1, IL4, IL13, IKBKB and FN1, and their reliability was verified using ROC curve. Single-cell RNA sequencing data analysis showed that these core target proteins mainly played a role by modulating monocytes. The anti-RA effect of EMO was further verified with MH7A cells, which showed that EMO could block cell differentiation and reduce the expression of IL-6 and IL-1β. WB experiments confirmed that EMO could affect the expression of COX2, HMBG1 and the phosphorylation of p38. Finally, sequencing of synovial fibroblasts from rats treated with EMO showed consistent results with those predicted and verified, further proving the anti-inflammatory effect of EMO. Conclusion: Our research shows that EMO inhibits inflammatory response of rheumatoid arthritis (RA) by targeting HMGB1, STAT1, EGR1, NR3C1, EGFR, MAPK14, CASP3, CASP1, IL4, IL13, IKBKB, FN1 and Monocytes/macrophages.

Anti-inflammatory mechanism of the optimized active ingredients of Sargentodoxa cuneata and Patrinia villosa

Pelvic inflammatory disease (PID) is a common gynecological infection. The combined use of Sargentodoxa cuneata (da xue teng) and Patrinia villosa (bai jiang cao) has been shown to inhibit PID progression. The active components of S. cuneata (emodin, Emo) and P. villosa (acacetin, Aca; oleanolic acid, OA; sinoacutine, Sin) have been identified but the mode of action of this combination of compounds against PID has not been clarified. Therefore, this study aims to investigate the mechanism of these active components against PID through network pharmacological, molecular docking and experimental validation. The results showed the optimal combination of components was 40 µM Emo + 40 µM OA, 40 µM Emo + 40 µM Aca, and 40 µM Emo + 150 µM Sin by cell proliferation and NO release. The potential key targets of this combination in the treatment of PID include SRC, GRB2, PIK3R1, PIK3CA, PTPN11, and SOS1, which act on signaling pathways such as EGFR, PI3K/Akt, TNF, and IL-17. Emo, Aca, OA, and their optimal combination inhibited the expression of IL-6, TNF-α, MCP-1, IL-12p70, IFN-γ, and the M1 phenotype markers CD11c and CD16/32, and promoted the expression of the M2 phenotype markers CD206 and arginase 1 (Arg1). Western blotting confirmed that Emo, Aca, OA, and their optimal combination significantly inhibited the expression of glucose metabolism-related proteins PKM2, PD, HK I, and HK II. This study proved the advantage of combination use of active components from S. cuneata and P. villosa, and clarified that they exert the anti-inflammatory effect by regulation of M1/M2 phenotype transition and regulation of glucose metabolism. The results provide a theoretical basis for the clinical treatment of PID.

Emodin Alcohols: Design, Synthesis, Biological Evaluation and Multitargeting Studies with DNA, RNA, and HSA

OBJECTIVE

A series of novel emodin alcohols were designed and prepared in an effort to overcome the increasing microorganism resistance.

METHODS

Novel emodin alcohols were prepared from commercial emodin and different nitrogen-containing heterocycles via different synthetic strategies, such as O-alkylation and N-alkylation. The antimicrobial activity of synthesized emodin compounds was evaluated in vitro by a two-fold serial dilution technique. The interaction of emodin compound 3d with biomolecule was researched using UV-vis spectroscopic method and fluorescence spectroscopy.

RESULTS

Emodin compound 3d containing 2-methyl-5-nitro imidazole ring showed relatively good antimicrobial activity. Notably, it exhibited equivalent activity against S. aureus in comparison to the reference drug norfloxacin (MIC = 4 g/mL). The combination of strong active compound 3d with reference drugs showed better antimicrobial activity with less dosage and a broader antimicrobial spectrum than their separate use. Further research displayed that emodin compound 3d could intercalate into S. aureus DNA to form the 3d-DNA complex, which might correlate with the inhibitory activity. The hydrogen bonds were found between S. aureus DNA gyrase and strong active compound 3d during the docking research, which were in accordance with the spectral experiment results. The interaction with yeast RNA of compound 3d could also form a complex via hydrogen bonds. The hydrogen bonds were found to play a major role in the transportation of emodin compound 3d by human serum albumin (HSA), as confirmed by molecular simulation.

CONCLUSION

This work provides a promising starting point to optimize the structures of emodin derivatives as potent antimicrobial agents.

Bio-efficacy of insecticidal molecule emodin against dengue, filariasis, and malaria vectors

Emodin, a compound isolated from Aspergillus terreus, was studied using chromatographic and spectroscopic methods and compound purity (96%) was assessed by TLC. Furthermore, high larvicidal activity against Aedes aegypti-AeA (LC₅₀ 6.156 and LC₉₀ 12.450 mg/L), Culex quinquefasciatus-CuQ (8.216 and 14.816 mg/L), and Anopheles stephensi-AnS larvae (6.895 and 15.24 mg/L) was recorded. The first isolated fraction (emodin) showed higher pupicidal activity against AeA (15.449 and 20.752 mg/L). Most emodin-treated larvae (ETL) showed variations in acetylcholine esterase, α and β-carboxylesterases, and phosphatase activities in the 4^th instar, indicating the intrinsic differences in their biochemical changes. ETL had numerous altered tissues, including muscle, gastric caeca, hindgut, midgut, nerve ganglia, and midgut epithelium. Acute toxicity of emodin on brine shrimp Artemia nauplii (54.0 and 84.5 mg/L) and the zebrafish Danio rerio (less toxicity observed) was recorded. In docking studies, Emodin interacted well with odorant-binding-proteins of AeA, AnS, and CuQ with docking scores of - 8.89, - 6.53, and - 8.09 kcal mol^-1, respectively. Therefore, A. terreus is likely to be effective against mosquito larvicides.

Emodin prevents renal ischemia-reperfusion injury via suppression of p53-mediated cell apoptosis based on network pharmacology

Background

Previous evidence indicated that emodin has significant advantages for preventing acute kidney injury (AKI). However, the mechanisms responsible for these effects of emodin have yet to be elucidated.

Methods

We first used network pharmacology and molecular docking to identify the core targets of emodin for AKI and performed a range of experiments to validate this result. Pretreatment with emodin for 7 days, the rats were treated with bilateral renal artery clipping for 45 min to identify the prevention effect. Hypoxia/reoxygenation (H/R), and vancomycin - induced renal tubular epithelial cells (HK-2 cells) were treated with emodin to explore the related molecular mechanism.

Results

Network pharmacology and molecular docking showed that anti-apoptosis might be the core mechanism responsible for the action of emodin on AKI; this anti-apoptotic effect appears to because by regulation p53-related signaling pathway. Our data showed that pretreatment with emodin significantly improved renal function and renal tubular injury in renal I/R model rats (P < 0.05. The prevention effect of emodin was proved to be related to anti - apoptosis of HK-2 cells, possibly by downregulating the levels of p53, cleaved-caspase-3, pro-caspase-9, and upregulated the levels of Bcl-2. The efficacy and mechanism of emodin on anti - apoptosis was also confirmed in vancomycin - induced HK-2 cells. Meanwhile, the data also showed that emodin promoted angiogenesis in I/R damaged kidneys and H/R-induced HK-2 cells, which was associated with decreasing HIF-1α levels and increasing VEGF levels.

Conclusions

Our findings indicated that the preventive effect of emodin on AKI is probably attributable to anti-apoptosis response and promoting angiogenesis effect.

Emodin-Induced Necroptosis in Prostate Cancer Cells via the Mitochondrial Fission HSP90/MLKL/PGAM Pathway

Prostate cancer is currently one of the major malignant tumors in males. The main barriers to effective prostate cancer treatment are recurrence and metastasis. Our study showed that emodin (EG) drastically reduced the cell viability of PC3 and DU145 cells and strikingly induced necroptosis that was visualized through colony formation assay, Hoechst 33258 staining, and TEM analysis. Furthermore, it was discovered by RNA-sequencing and KEGG functional enrichment analysis that EG treatment of PC3 cells activated the necroptosis-related pathway. By using qPCR and immunoblotting to analyze the mRNA and protein expression of necroptosis markers, it was determined that EG-induced cell necroptosis via increasing the expression of MLKL and HSP90AA1 activating PGAM pathway which is thought to be a key mediator of mitochondrial fission and the production of ROS in PC3 and DU145 cells. Our results, therefore, revealed that EG is a novel small molecule agonist that activated the HSP90/MLKL/PGAM pathway to induce necroptosis in prostate cancer cells.

Role of emodin in atherosclerosis and other cardiovascular diseases: Pharmacological effects, mechanisms, and potential therapeutic target as a phytochemical

The morbidity and mortality of cardiovascular diseases (CVDs) are increasing in recent years, and atherosclerosis (AS), a major CVD, becomes a disorder that afflicts human beings severely, especially the elders. AS is recognized as the primary cause and pathological basis of some other CVDs. The active constituents of Chinese herbal medicines have garnered increasing interest in recent researches owing to their influence on AS and other CVDs. Emodin (1,3,8-trihydroxy-6-methylanthraquinone) is a naturally occurring anthraquinone derivative found in some Chinese herbal medicines such as Rhei radix et rhizome, Polygoni cuspidati rhizoma et radix and Polygoni multiflori root. In this paper, we first review the latest researches about emodin's pharmacology, metabolism and toxicity. Meanwhile, it has been shown to be effective in treating CVDs caused by AS in dozens of previous studies. Therefore, we systematically reviewed the mechanisms by which emodin treats AS. In summary, these mechanisms include anti-inflammatory activity, lipid metabolism regulation, anti-oxidative stress, anti-apoptosis and vascular protection. The mechanisms of emodin in other CVDs are also discussed, such as vasodilation, inhibition of myocardial fibrosis, inhibition of cardiac valve calcification and antiviral properties. We have further summarized the potential clinical applications of emodin. Through this review, we hope to provide guidance for clinical and preclinical drug development.

Effect of Zn2+ on emodin molecules studied by time-resolved fluorescence spectroscopy and quantum chemical calculations

Emodin is a natural drug for treating neurodegenerative diseases and plays a vital role in the mitigation of nerve damage. Metal ions can modify the drug properties of emodin, where Zn²⁺ can synergize with the emodin molecule and enhance the drug effect of emodin. Besides, complex changes can be observed in the fluorescence intensity and fluorescence lifetime of the emodin molecule as the concentration of Zn²⁺ increases. Herein, the synergistic effects of ligand structural in Zn(II)-Emodin complexes and the electronic effects of metal elements on the antioxidant properties of the complexes are discussed in detail based on UV-vis absorption spectroscopy, fluorescence spectroscopy, time-correlated single photon counting (TCSPC) technique and quantum chemical calculations at the B3LYP/6-31G(d) level. The experimental results confirm that Zn²⁺ can coordinate with the hydroxyl groups on the emodin to make the molecule structure more rigid, thus inhibiting the non-radiative processes such as high-frequency vibrations of the emodin molecule in solution. The suppression of non-radiative processes leads to an increase in the average fluorescence lifetime of the emodin molecule, and finally results in the enhanced fluorescence intensity. The chemical softness of Zn(II)-Emodin is then confirmed to be higher than that of emodin by Gaussian calculations, indicating its higher chemical reactivity and lower stability. The stronger electron donating ability of Zn(II)-Emodin compared to emodin may explain the higher antioxidant activity of Zn(II)-Emodin, which gives it a stronger pharmacological activity. The results of this study show that emodin can well complex with Zn²⁺ to remove excess Zn²⁺ in human body and the resulting complex has better antioxidant properties, which helps to understand the role of Zn²⁺ in drug-metal coordination and provides guidance for the design of new drugs.

Emodin alleviates testicular ischemia-reperfusion injury through the inhibition of NLRP3-mediated pyroptosis

Ischemia-reperfusion injury (IRI) is a major cause of injury after testicular torsion and can lead to permanent impairment of spermatogenesis. Emodin (6-methyl-1,3,8-trihydroxyanthraquinone) has potent anti-inflammatory effects and may be protective against IRI in various organs. Herein, we evaluated the effects of emodin on pyroptosis in spermatogenic cells and its role in the process of testicular IRI. A testicular torsion/detorsion (TTD) mouse model and an oxygen-glucose deprivation/reperfusion (OGD/R) germ cell model were established. Hematoxylin and eosin staining was performed to evaluate the testicular ischemic injury. The expression of pyroptosis-related proteins and reactive oxygen species production in testis tissues were detected using Western blotting, quantitative real-time PCR, malondialdehyde and superoxide dismutase assay kits and immunohistochemistry. Cell viability and cytotoxicity were evaluated using Cell Counting Kit-8 and lactate dehydrogenase assay kit. Enzyme-linked immunosorbent assay, immunofluorescence and immunoblotting were performed to assess inflammatory protein levels. The results revealed that pyroptosis and inflammation levels were upregulated after testicular IRI, and emodin inhibited inflammation and pyroptosis by acting on NOD-like receptor thermal protein domain-associated protein 3 (NLRP3). Emodin exerts protective effects on testicular IRI by acting on the NLRP3 signaling pathway and inhibiting IRI-mediated pyroptosis. Emodin treatment attenuated testicular IRI and inhibited pyroptosis. Inhibitory effects of emodin on pyroptosis were attributed to the inhibition of NLRP3 inflammasomes. Thus, emodin could be an alternative treatment for testicular IRI.

Structure-based virtual screening of chemical libraries as potential MELK inhibitors and their therapeutic evaluation against breast cancer

New targeted therapy for triple negative breast cancer (TNBC) is an urgent need, as advanced disease responds poorly to conventional chemotherapy. Genomic and proteomic studies are currently investigating new genes and proteins as promising therapeutic targets. One of such therapeutic targets is a cell cycle regulatory kinase; Maternal Embryonic Leucine Zipper Kinase (MELK), overexpressed in TNBC and correlated with cancer development. We performed molecular docking for virtual screening of chemical libraries (phytochemicals/synthetic drugs) against MELK protein structure and identified 8 phytoconstituents (isoxanthorin, emodin, gamma-coniceine, quercetin, tenuazonic acid, isoliquiritigenin, kaempferol, and Nobiletin) and 8 synthetic drugs (tetrahydrofolic acid, alfuzosin, lansoprazole, ketorolac, ketoprofen, variolin B, orantinib, and firestein) as potential hits interacting with the active site residues of MELK based on bound poses, hydrogen bond, hydrophobic interactions and MM/GBSA binding free energies. ADME and drug-likeness prediction further identified few hits with high drug-likeness properties and were further tested for anti-tumorigenic potential. Two phytochemicals isoliquiritigenin and emodin demonstrated growth inhibitory effects on TNBC MDA-MB-231 cells while much lower effect was observed on non-tumorigenic MCF-10A mammary epithelial cells. Treatment with both molecules downregulated MELK expression, induced cell cycle arrest, accumulated DNA damage and enhanced apoptosis. The study identified isoliquiritigenin and emodin as potential MELK inhibitors and provides a basis for subsequent experimental validation and drug development against cancer.

Emodin inhibiting epithelial-mesenchymal transition in pulmonary fibrosis through the c-MYC/miR-182-5p/ZEB2 axis

Emodin is a natural anthraquinone compound, which is the main component found in the traditional Chinese herb Polygonum cuspidatum. The anti-fibrosis effects of Emodin have been reported. This study aimed to explore the specific mechanism of Emodin in the epithelial-mesenchymal transition (EMT) of pulmonary fibrosis. The pulmonary fibrosis mice models were constructed with bleomycin, the EMT models of alveolar epithelial cells were stimulated by TGF-β1, and Emodin was used for intervention. c-MYC and miR-182-5p were overexpressed or silenced by cell transfection. Our results demonstrated that Emodin attenuated pulmonary fibrosis induced by bleomycin in mice, and inhibited EMT, meanwhile downregulated c-MYC, upregulated miR-182-5p, and downregulated ZEB2 in vitro and vivo. Next, overexpression of c-MYC promoted EMT, while silencing c-MYC and overexpressing miR-182-5p inhibited EMT. Then, c-MYC negatively regulated the expression of miR-182-5p with a direct binding relationship. And miR-182-5p inhibited ZEB2 expression in a targeted manner. Finally, Emodin inhibited EMT that had been promoted by overexpression of c-MYC. In conclusion, Emodin could attenuate pulmonary fibrosis and EMT by regulating the c-MYC/miR-182-5p/ZEB2 axis, which might provide evidence for the application of Emodin in the treatment of pulmonary fibrosis.

A comprehensive review of emodin in fibrosis treatment

Emodin is the main pharmacodynamic components of rhubarb, with significant pharmacological effects and clinical efficacy.Emodin has a variety of therapy effects, such as anti-cancer, anti-fibrosis effects, and is widely used to treat encephalitis, diabetic cataract and organ fibrosis. Several studies have shown that emodin has a good treatment effect on organ fibrosis, but the mechanism is complex. Moreover, the evidence of some studies is conflicting and confusing. This paper reviewed the mechanism, pharmacokinetics and toxicology of emodin in fibrosis treatment, and briefly discussed relevant cutting-edge new formulations to improve the efficacy, the result can provide some reference for future study.

Recent advances in the identification of biosynthetic genes and gene clusters of the polyketide-derived pathways for anthraquinone biosynthesis and biotechnological applications

Natural anthraquinones are represented by a large group of compounds. Some of them are widespread across the kingdoms, especially in bacteria, fungi and plants, while the others are restricted to certain groups of organisms. Despite the significant pharmacological potential of several anthraquinones (hypericin, skyrin and emodin), their biosynthetic pathways and candidate genes coding for key enzymes have not been experimentally validated. Understanding the genetic and epigenetic regulation of the anthraquinone biosynthetic gene clusters in fungal endophytes would help not only understand their pathways in plants, which ensure their commercial availability, but also favor them as promising systems for prospective biotechnological production.

Emodin protects against homocysteine-induced cardiac dysfunction by inhibiting oxidative stress via MAPK and Akt/eNOS/NO signaling pathways

Elevated levels of plasma homocysteine (Hcy) causes severe cardiac dysfunction, which is closely associated with oxidative stress. Emodin, a naturally occurring anthraquinone derivative, has been shown to exert antioxidant and anti-apoptosis activities. However, whether emodin could protect against Hcy-induced cardiac dysfunction remains unknown. The current study aimed to investigate the effects of emodin on the Hcy-induced cardiac dysfunction and its molecular mechanisms. Rats were fed a methionine diet to establish the animal model of hyperhomocysteinemia (HHcy). H9C2 cells were incubated with Hcy to induce a cell model of Hcy-injured cardiomyocytes. ELISA, HE staining, carotid artery and left ventricular cannulation, MTT, fluorescence staining, flow cytometry and western blotting were used in this study. Emodin significantly alleviated the structural damage of the myocardium and cardiac dysfunction from HHcy rats. Emodin prevented apoptosis and the collapse of MMP in the Hcy-treated H9C2 cells in vitro. Further, emodin reversed the Hcy-induced apoptosis-related biochemical changes including decreased Bcl-2/Bax protein ratio, and increased protein expression of Caspase-9/3. Moreover, emodin suppressed oxidative stress in Hcy-treated H9C2 cells. Mechanistically, emodin significantly inhibited the Hcy-activated MAPK by reducing ROS generation in H9C2 cells. Furthermore, emodin upregulated NO production by promoting the protein phosphorylation of Akt and eNOS in injured cells. The present study shows that emodin protects against Hcy-induced cardiac dysfunction by inhibiting oxidative stress via MAPK and Akt/eNOS/NO signaling pathways.