Potential Mechanism by which Eriodictyol Protects against Doxorubicininduced Cardiotoxicity based on Network Pharmacology, Molecular Docking, and Molecular Dynamics Simulation.

BACKGROUND: The clinical use of doxorubicin (DOX), an anthracycline antibiotic with broad-spectrum applications against various malignant tumors, is limited by doxorubicininduced cardiotoxicity (DIC). Eriodictyol (ERD) has shown cardioprotective effects, but the mechanism of its protective effect on DIC remains unknown. AIMS: This study aimed to explore the potential mechanisms by which ERD confers protection against DIC. METHODS: ERD and DIC targets were identified from the TCMSP, PharmMaper, SwissTargetPrediction, TargetNet, BATMAN, GeneCards, and PharmGKB databases. Differential gene expression data between DIC and normal tissues were extracted from the GEO database. A protein‒ protein interaction (PPI) network of the intersecting ERD-DIC targets was constructed using the STRING platform and visualized with Cytoscape 3.10.0 software. Gene Ontology (GO) functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis for ERD-DIC cross-targets were conducted. Validation included molecular docking with AutoDock Tools software and molecular dynamics simulations with Gromacs 2019.6 software. RESULTS: Network pharmacology analysis revealed 43 intersecting ERD-DIC targets, including 6 key targets. GO functional enrichment analysis indicated that the intersecting targets were enriched in 550 biological processes, 45 cell components, and 41 molecular functions. KEGG pathway enrichment analysis identified 114 enriched signaling pathways. Molecular docking revealed a strong binding affinity between ERD and 6 key targets, as well as multiple targets within the ROS pathway. Molecular dynamics simulations indicated that ERD has favorable binding with 3 crucial targets. CONCLUSION: The systematic network pharmacology analysis suggests that ERD may mitigate DIC through multiple targets and pathways, with the ROS pathway potentially playing a crucial role. These findings provide a reference for foundational research and clinical applications of ERD in treating DIC.

The Potential Mechanism of Eriodictyol in Treating Alzheimer's Disease: A Study on Computer-assisted Investigational Strategies.

BACKGROUND: At present, drug development for treating Alzheimer's disease (AD) is still highly challenging. Eriodictyol (ERD) has shown great potential in treating AD, but its molecular mechanism is unknown. OBJECTIVE: We aimed to explore the potential targets and mechanisms of ERD in the treatment of AD through network pharmacology, molecular docking, and molecular dynamics simulations. METHODS: ERD-related targets were predicted based on the CTD, SEA, PharmMapper, Swiss TargetPrediction, and ETCM databases, and AD-related targets were predicted through the TTD, OMIM, DrugBank, GeneCards, Disgenet, and PharmGKB databases. Protein-protein interaction, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomics analyses (KEGG) were used to analyse the potential targets and key pathways of the anti-AD effect of ERD. Subsequently, potential DEGs affected by AD were analysed using the AlzData database, and their relationships with ERD were evaluated through molecular docking and molecular dynamics simulations. RESULTS: A total of 198 ERD-related targets, 3716 AD-related targets, and 122 intersecting targets were identified. GO annotation analysis revealed 1497 biological processes, 78 cellular components, and 132 molecular functions of 15 core targets. KEGG enrichment analysis identified 168 signalling pathways. We ultimately identified 9 DEGs associated with AD through analysis of the AlzData data. Molecular docking results showed good affinity between the selected targets and ERD, with PTGS2, HSP90AA1, and BCL2. The interactions were confirmed by molecular dynamics simulations. CONCLUSION: ERD exerts anti-AD effects through multiple targets, pathways, and levels, providing a theoretical foundation and valuable reference for the development of ERD as a natural anti-AD drug.

Bioactivity of 2-(3,4-Dihydroxyphenyl)-5,7-dihydroxy-2,3-dihydrochromen-4-one from pistacia chinensis on ENPP1 and aldose reductase.

Pistacia chinensis is used as a decorative tree and currently studied as a source of biofuels. Besides, its parts and extracts are endowed with several therapeutic uses which have been widely explored in traditional medicine and that are related to its rich composition in phytochemicals. Molecular docking and enzymatic inhibition tests were used to study the activity of eriodictyol, a flavonoid extracted from the barks of P. chinensis, against ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) and aldose reductase (ALR2). The compound was highlighted as a micromolar inhibitor in vitro (IC50 = 263.76 ± 1.32 µM and 4.21 ± 0.94 µM, respectively) and docking showed that eriodictyol efficiently targets the binding sites of the enzymes. In conclusion, this study unveils the potential of eriodictyol on enzymes that are involved in immunostimulation and in complications of diabetes mellitus.

Artemisia argyi extracts overcome lapatinib resistance via enhancing TMPRSS2 activation in HER2-positive breast cancer.

Breast cancer stands as the predominant malignancy and primary cause of cancer-related mortality among females globally. Approximately 25% of breast cancers exhibit HER2 overexpression, imparting a more aggressive tumor phenotype and correlating with poor prognoses. Patients with metastatic breast cancer receiving HER2 tyrosine kinase inhibitors (HER2 TKIs), such as Lapatinib, develop acquired resistance within a year, posing a critical challenge in managing this disease. Here, we explore the potential of Artemisia argyi, a Chinese herbal medicine known for its anti-cancer properties, in mitigating HER2 TKI resistance in breast cancer. Analysis of the Cancer Genome Atlas (TCGA) revealed diminished expression of transmembrane serine protease 2 (TMPRSS2), a subfamily of membrane proteolytic enzymes, in breast cancer patients, correlating with unfavorable outcomes. Intriguingly, lapatinib-responsive patients exhibited higher TMPRSS2 expression. Our study unveiled that the compounds from Artemisia argyi, eriodictyol, and umbelliferone could inhibit the growth of lapatinib-resistant HER2-positive breast cancer cells. Mechanistically, they suppressed HER2 kinase activation by enhancing TMPRSS2 activity. Our findings propose TMPRSS2 as a critical determinant in lapatinib sensitivity, and Artemisia argyi emerges as a potential agent to overcome lapatinib via activating TMPRSS2 in HER2-positive breast cancer. This study not only unravels the molecular mechanisms driving cell death in HER2-positive breast cancer cells induced by Artemisia argyi but also lays the groundwork for developing novel inhibitors to enhance therapy outcomes.

Eriodictyol attenuates doxorubicin-induced nephropathy by activating the AMPK/Nrf2 signalling pathway.

Doxorubicin (DOX), an anthracycline chemotherapy, plays a prominent role in the treatment of various cancers. Unfortunately, its nephrotoxic effects limit its dosing and expose cancer survivors to increased morbidity and mortality. This study examined the nephroprotective effects of eriodictyol, a natural polyphenolic flavanone, in DOX-treated rats and the molecular pathways involved. Forty adult rats were divided into five groups (8/group): Control; eriodictyol (20 mg/kg/day); DOX (2.5 mg/kg, twice/week); DOX + Eriodictyol; and DOX + Eriodictyol + Compound C (CC), an AMPK inhibitor (0.2 mg/kg/day). Experiments continued for 21 days. Eriodictyol administration in DOX-treated rats reduced their fasting glucose levels and increased food intake, final body weight, and kidney weight, improved kidney function, prevented glomerular and tubular damage, and reduced collagen deposition and renal TGF-ß1 mRNA levels. Furthermore, eriodictyol reduced their renal levels of Bax, caspase-3, and cytochrome-c; and enhanced the levels of Bcl2. Noticeably, in the kidneys of both controls and DOX-treated rats, eriodictyol increased levels of phosphorylated-AMPK(Thr172) but not AMPK mRNA nor protein levels. Also, in the same two groups, eriodictyol increased mRNA and nuclear Nrf2 levels, and levels of glutathione, superoxide dismutase, catalase, and hemeoxygenase-1, but reduced the levels of malonaldehyde, TNF-α, and mRNA, total, and nuclear levels of NF-κB. All the detected nephroprotective effects and improvements in the levels of markers of oxidation and inflammation were prevented by coadministration of CC. In conclusion, the coadministration of eriodictyol and DOX alleviates DOX-induced renal damage. In renal tissues, eriodictyol is an AMPK activator and its nephroprotective antioxidant and anti-inflammatory effects are AMPK-dependent.

Eriodictyol inhibits the motility, angiogenesis and tumor growth of hepatocellular carcinoma via NLRP3 inflammasome inactivation.

NLRP3 involves in the development of hepatocellular carcinoma (HCC). Eriodictyol has shown its inhibitory effect on HCC cell proliferation. However, the underlying mechanism of eriodictyol in HCC is still unclear. This study aimed to explore the effect of and mechanism of eriodictyol on HCC. In this study, compared with eriodictyol (0 µM) group, eriodictyol significantly suppressed HepG2 cells (eriodictyol of 25, 50 and 100 µM) and Huh-7 cells (eriodictyol of 50 and 100 µM) viability, invasion, tube formation, metastasis-related genes MMP3, MMP16 and angiogenesis regulator VEGFA expressions with IC50 of 45.63 µM and 78.26 µM in vitro, respectively. Besides, eriodictyol significantly repressed NLRP3 expression, and reduced the protein levels of NLRP3 inflammasome-related proteins, adapter protein ASC, caspase-1, interleukin (IL)-18, and IL-1ß in HepG2 (eriodictyol of 25, 50 and 100 µM) and Huh-7 cells (eriodictyol of 50 and 100 µM), respectively. Meanwhile, compared with control group, NLRP3 overexpression reversed the anti-metastatic effects of 100 µM eriodictyol on HCC cells invasion, tube formation, and metastasis-related genes MMP3, MMP16 and angiogenesis regulator VEGFA expressions, whereas NLRP3 knockdown enhanced the anti-metastatic effects of 100 µM eriodictyol on HCC cells. In vivo, compared with control group, eriodictyol significantly reduced the tumor growth, liver damage, inhibited the activation of NLRP3 inflammasome, and improved liver function, whereas NLRP3 overexpressing neutralized the anti-tumor effects of eriodictyol and degraded liver function. Hence, eriodictyol inhibited HCC cell viability, motility, angiogenesis and tumor growth via NLRP3 inflammasome inactivation both in vitro and in vivo.

Systems Metabolic Engineering of Saccharomyces cerevisiae for the High-Level Production of (2S)-Eriodictyol.

(2S)-eriodictyol (ERD) is a flavonoid widely found in citrus fruits, vegetables, and important medicinal plants with neuroprotective, cardioprotective, antidiabetic, and anti-obesity effects. However, the microbial synthesis of ERD is limited by complex metabolic pathways and often results in a low production performance. Here, we engineered Saccharomyces cerevisiae by fine-tuning the metabolism of the ERD synthesis pathway. The results showed that the ERD titer was effectively increased, and the intermediate metabolites levels were reduced. First, we successfully reconstructed the de novo synthesis pathway of p-coumaric acid in S. cerevisiae and fine-tuned the metabolic pathway using promoter engineering and terminator engineering for the high-level production of (2S)-naringenin. Subsequently, the synthesis of ERD was achieved by introducing the ThF3'H gene from Tricyrtis hirta. Finally, by multiplying the copy number of the ThF3'H gene, the production of ERD was further increased, reaching 132.08 mg L-1. Our work emphasizes the importance of regulating the metabolic balance to produce natural products in microbial cell factories.

High-Level De Novo Production of (2S)-Eriodictyol in Yarrowia Lipolytica by Metabolic Pathway and NADPH Regeneration Engineering.

(2S)-Eriodictyol, a polyphenolic flavonoid, has found widespread applications in health supplements and food additives. However, the limited availability of plant-derived (2S)-eriodictyol cannot meet the market demand. Microbial production of (2S)-eriodictyol faces challenges, including the low catalytic efficiency of flavone 3'-hydroxylase/cytochrome P450 reductase (F3'H/CPR), insufficient precursor supplementation, and inadequate NADPH regeneration. This study systematically engineered Yarrowia lipolytica for high-level (2S)-eriodictyol production. In doing this, the expression of F3'H/CPR was balanced, and the supply of precursors was enhanced by relieving feedback inhibition of the shikimate pathway, promoting fatty acid ß-oxidation, and increasing the copy number of synthetic pathway genes. These strategies, combined with NADPH regeneration, achieved an (2S)-eriodictyol titer of 423.6 mg/L. Finally, in fed-batch fermentation, a remarkable 6.8 g/L (2S)-eriodictyol was obtained, representing the highest de novo microbial titer reported to date and paving the way for industrial production.

Biosynthesis of eriodictyol in citrus waster by endowing P450BM3 activity of naringenin hydroxylation.

The flavonoid naringenin is abundantly present in pomelo peels, and the unprocessed naringenin in wastes is not friendly for the environment once discarded directly. Fortunately, the hydroxylated product of eriodictyol from naringenin exhibits remarkable antioxidant and anticancer properties. The P450s was suggested promising for the bioconversion of the flavonoids, but less naturally existed P450s show hydroxylation activity to C3' of the naringenin. By well analyzing the catalytic mechanism and the conformations of the naringenin in P450, we proposed that the intermediate Cmpd I ((porphyrin)Fe = O) is more reasonable as key conformation for the hydrolyzation, and the distance between C3'/C5' of naringenin to the O atom of CmpdI determines the hydroxylating activity for the naringenin. Thus, the "flying kite model" that gradually drags the C-H bond of the substrate to the O atom of CmpdI was put forward for rational design. With ab initio design, we successfully endowed the self-sufficient P450-BM3 hydroxylic activity to naringenin and obtained mutant M5-5, with kcat, Km, and kcat/Km values of 230.45 min-1, 310.48 µM, and 0.742 min-1 µM-1, respectively. Furthermore, the mutant M4186 was screened with kcat/Km of 4.28-fold highly improved than the reported M13. The M4186 also exhibited 62.57% yield of eriodictyol, more suitable for the industrial application. This study provided a theoretical guide for the rational design of P450s to the nonnative compounds. KEY POINTS: •The compound I is proposed as the starting point for the rational design of the P450BM3 •"Flying kite model" is proposed based on the distance between O of Cmpd I and C3'/C5' of naringenin •Mutant M15-5 with 1.6-fold of activity than M13 was obtained by ab initio modification.

Preparation and quality evaluation of Eriodictyol chewable tablet / 中国药房

OBJECTIVE To prepare the Eriodictyol chewable tablet and to evaluate its quality. METHODS The chewable tablet was prepared by the wetting granulation method by using microcrystalline cellulose （MCC） and mannitol as fillers， polyvinylpyrrolidone （PVP） as adhesive， citric acid and sucralose as flavor correction agents， magnesium stearate as lubricant. The comprehensive evaluation was conducted on Eriodictyol chewable tablets with the dosage of each excipient as a factor using the appearance， taste， flavor and texture as indicators. The ratio of excipients was optimized by orthogonal test， and the quality of Eriodictyol chewable tablets prepared by optimized formulation was evaluated in terms of appearance， weight difference， hardness， fragility， eriodictyol content， dissolution and content uniformity. RESULTS The optimal formulation was as follows： 26.4% eriodictyol （50 mg each piece）， 45% mannitol， 25% MCC， 0.3% citric acid， 0.3% sucralose， 1% magnesium stearate， 2% PVP （preparing 5% solution using purified water）. The scores of 3 batches of Eriodictyol chewable tablets in the validation test were 8.76， 8.75 and 8.80 （RSD＝0.30%， n＝3）， respectively. The Eriodictyol chewable tablet had a complete appearance and a smooth surface； the average tablet weight was 192.57 mg， the average hardness was 57.36 N， the fragility was 0.09%， the average content of eriodictyol per tablet was 50.74 mg， the cumulative dissolution within 30 min was exceeding 80%， and the content uniformity was 5.51. CONCLUSIONS Eriodictyol chewable tablet prepared by optimal formulation conforms to the requirements of the 2020 edition of Chinese Pharmacopoeia.

Protective effect of eriodictyol against hyperglycemia-induced diabetic nephropathy in rats entails antioxidant and anti-inflammatory effects mediated by activating Nrf2.

The pathogenesis of diabetic nephropathy (DN) involves cellular activation of oxidative stress and inflammation. Eriodictyol is a citrus-derived flavonoid with multiple pharmacological and protective effects in various conditions. The protective role of Eriodictyol against diabetes and diabetic nephropathy is less investigated. The current research aimed to explore the role of eriodictyol in protecting against DN prompted by streptozotocin in male rats and investigate some possible mechanisms of action. Diabetes was brought about in rats by an i.p injection of a lone dose (65 mg/kg). Five groups of rats were included (n = 8 each) as control (non-diabetic), eriodictyol (20 mg/kg, orally), STZ-diabetic, STZ + eriodictyol (20 mg/kg, orally), and STZ + eriodictyol (20 mg/kg, orally) + ML385 (30 µg/kg, i.p.). Kidney histology and the levels of some markers of kidney function, renal oxidative stress, and renal inflammation were analyzed in all groups of rats. Treatment with eriodictyol prevented the damage in the renal glomeruli and tubules and reduced renal immune cell infiltration in STZ-treated animals. It also spiked urinary creatinine excretion and reduced urine volume and urinary levels of albumin, monocyte chemoattractant protein 1 (MCP-1), urinary kidney injury molecule-1 (KIM-1), and nephrin in these diabetic rats. In addition, eriodictyol stimulated the nuclear protein accumulation of Nrf2 and boosted the expression of superoxide dismutase (SOD), glutathione (GSH), heme oxygenase-1 (HO-1), and catalase (CAT) in the diabetic rat kidneys. In concomitance, it reduced the nuclear levels of NF-κB and levels of interleukine-6 (IL-6), malondialdehyde (MDA), and tumor necrosis factor-α (TNF-α) and attenuated the reduction in renal ATP levels and the increase in the mitochondria transition pore opening (mtTPT). However, the administration of eriodictyol did not affect rats' body weights and fasting glucose and insulin levels but significantly reduced serum levels of cholesterol, triglycerides, LDL-c, and oxidized LDL-c (ox-LDL-c). In conclusion, eriodictyol prevents STZ-induced nephropathy by a hypolipidemic effect and concomitant antioxidant and anti-inflammatory effects mediated by activating Nrf2/NF-κB/antioxidant axis.

Eriodictyol Alleviated LPS/D-GalN-Induced Acute Liver Injury by Inhibiting Oxidative Stress and Cell Apoptosis via PI3K/AKT Signaling Pathway.

Eriodictyol occurs naturally in a variety of fruits and vegetables, and has drawn significant attention for its potential health benefits. This study aims to look into the effects of eriodictyol on acute liver injury (ALI) induced by LPS/D-GalN and elucidate its potential molecular biological mechanisms. A total of 47 targets were predicted for the treatment of ALI with eriodictyol, and the PI3K/AKT signaling pathway played a key role in the anti-ALI processing of this drug. The in vivo experiment showed that eriodictyol can effectively reduce liver function-related biochemical indicators such as ALT, AST, and AKP. Eriodictyol can also up-regulate the levels of SOD and GSH, and inhibit the release of IL-1ß, IL-6, and TNF-α. Additionally, TUNEL staining, immunohistochemistry, and RT-PCR experiments showed that eriodictyol activated the PI3K/AKT pathway and decreased the expression of Bax, caspase3, and caspase8 while increasing the expression of Bcl-2 m-RNA. Finally, molecular docking experiments and molecular dynamics simulations confirmed the stable binding between eriodictyol and PI3K, AKT molecules. This study showed that eriodictyol can activate the PI3K/AKT signaling pathway to alleviate ALI-related oxidative stress and apoptosis.

A Comparison between High-Performance Countercurrent Chromatography and Fast-Centrifugal Partition Chromatography for a One-Step Isolation of Flavonoids from Peanut Hulls Supported by a Conductor like Screening Model for Real Solvents.

Peanut hulls (Arachis hypogaea, Leguminosae), which are a side stream of global peanut processing, are rich in bioactive flavonoids such as luteolin, eriodictyol, and 5,7-dihydroxychromone. This study aimed to isolate these flavonoid derivatives by liquid-liquid chromatography with as few steps as possible. To this end, luteolin, eriodictyol and 5,7-dihydroxychromone were isolated from peanut hulls using two different techniques, high-performance countercurrent chromatography (HPCCC) and fast-centrifugal partition chromatography (FCPC). The suitability of the biphasic solvent system composed of n-hexane/ethyl acetate/methanol/water (1.0/1.0/1.0/1.5; v/v/v/v) was determined by the Conductor like Screening Model for Real Solvents (COSMO-RS), which allowed the partition ratio KD-values of the three main flavonoids to be calculated. After a one-step HPCCC separation of ~1000 mg of an ethanolic peanut hull extract, 15 mg of luteolin and 8 mg of eriodictyol were isolated with purities over 96%. Furthermore, 3 mg of 5,7-dihydroxychromone could be isolated after purification by semi-preparative reversed-phase liquid chromatography (semi-prep. HPLC) in purity of over 99%. The compounds were identified by electrospray ionization mass spectrometry (ESI-MS) and nuclear magnetic resonance spectroscopy (NMR).

Umbelliferone and eriodictyol suppress the cellular entry of SARS-CoV-2.

BACKGROUND: Artemisia argyi (A. argyi), also called Chinese mugwort, has been widely used to control pandemic diseases for thousands of years since ancient China due to its anti-microbial infection, anti-allergy, and anti-inflammation activities. Therefore, the potential of A. argyi and its constituents in reducing the infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was investigated in this study. RESULTS: Among the phytochemicals in A. argyi, eriodictyol and umbelliferone were identified to target transmembrane serine protease 2 (TMPRSS2) and angiotensin-converting enzyme 2 (ACE2) proteins, the essential factors for the cellular entry of SARS-CoV-2, in both FRET-based enzymatic assays and molecular docking analyses. These two ingredients of A. argyi suppressed the infection of ACE2-expressed HEK-293 T cells with lentiviral-based pseudo-particles (Vpp) expressing wild-type and variants of SARS-CoV-2 spike (S) protein (SARS-CoV-2 S-Vpp) via interrupting the interaction between S protein and cellular receptor ACE2 and reducing the expressions of ACE2 and TMPRSS2. Oral administration with umbelliferone efficiently prevented the SARS-CoV-2 S-Vpp-induced inflammation in the lung tissues of BALB/c mice. CONCLUSIONS: Eriodictyol and umbelliferone, the phytochemicals of Artemisia argyi, potentially suppress the cellular entry of SARS-CoV-2 by preventing the protein binding activity of the S protein to ACE2.

Eriodictyol attenuates Furan induced testicular toxicity in Rats: Role of oxidative stress, steroidogenic enzymes and apoptosis.

Furan (C4H4O) is a naturally occurring organic compound. It develops as a result of the thermal processing of food and stimulates critical impairments in male reproductive tract. Eriodictyol (Etyol) is a natural dietary flavonoid possessing diverse pharmacological potentials. The recent investigation was proposed to ascertain the ameliorative potential of eriodictyol against furan-instigated reproductive dysfunctions. Male rats (n = 48) were classified into 4 groups: untreated/control, furan (10 mg/kg), furan+ eriodictyol (10 mg/kg + 20 mg/kg) and eriodictyol (20 mg/kg). At the 56th day of the trial, the protective effects of eriodictyol were evaluated by assessing various parameters. Results of the study revealed that eriodictyol attenuated furan-induced testicular toxicity in the biochemical profile by increasing catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD) along with glutathione reductase (GSR) activities, whereas reduced the reactive oxygen species (ROS) along with malondialdehyde (MDA) levels. It also restored the normal state of sperm motility, viability, the count of hypo-osmotic tail swelled sperm as well as epididymal sperm number along with reduced sperm anomalies (morphological) tail, mid-piece and head. Furthermore, it elevated the decreased levels of luteinizing hormone (LH), plasma testosterone and follicle-stimulating hormone (FSH) as well steroidogenic enzymes (17ß-HSD, StAR protein & 3ß-HSD) and testicular anti-apoptotic marker (Bcl-2) expression, whereas, down-regulating apoptotic markers (Bax & Caspase-3) expression. Eriodictyol treatment also effectively mitigated the histopathological damages. The outcomes of the current study provide fundamental insights into the ameliorative potential of eriodictyol against furan-instigated testicular toxicity.

Optimized De Novo Eriodictyol Biosynthesis in Streptomyces albidoflavus Using an Expansion of the Golden Standard Toolkit for Its Use in Actinomycetes.

Eriodictyol is a hydroxylated flavonoid displaying multiple pharmaceutical activities, such as antitumoral, antiviral or neuroprotective. However, its industrial production is limited to extraction from plants due to its inherent limitations. Here, we present the generation of a Streptomyces albidoflavus bacterial factory edited at the genome level for an optimized de novo heterologous production of eriodictyol. For this purpose, an expansion of the Golden Standard toolkit (a Type IIS assembly method based on the Standard European Vector Architecture (SEVA)) has been created, encompassing a collection of synthetic biology modular vectors (adapted for their use in actinomycetes). These vectors have been designed for the assembly of transcriptional units and gene circuits in a plug-and-play manner, as well as for genome editing using CRISPR-Cas9-mediated genetic engineering. These vectors have been used for the optimization of the eriodictyol heterologous production levels in S. albidoflavus by enhancing the flavonoid-3'-hydroxylase (F3'H) activity (by means of a chimera design) and by replacing three native biosynthetic gene clusters in the bacterial chromosome with the plant genes matBC (involved in extracellular malonate uptake and its intracellular activation into malonyl-CoA), therefore allowing more malonyl-CoA to be devoted to the heterologous production of plant flavonoids in this bacterial factory. These experiments have allowed an increase in production of 1.8 times in the edited strain (where the three native biosynthetic gene clusters have been deleted) in comparison with the wild-type strain and a 13 times increase in eriodictyol overproduction in comparison with the non-chimaera version of the F3'H enzyme.

Eriodictyol regulated ferroptosis, mitochondrial dysfunction, and cell viability via Nrf2/HO-1/NQO1 signaling pathway in ovarian cancer cells.

This study aimed to investigate the antitumor effect and the underlying molecular mechanism of eriodictyol on ovarian cancer cells. CaoV3 and A2780 were exposed to eriodictyol at different concentrations of 0-800 µM. Cell apoptosis and viability were determined by TdT-mediated dUTP Nick-End Labeling (TUNEL) assay and Cell Counting Kit-8 (CCK-8) assay, respectively. Mitochondrial membrane potential was evaluated by flow cytometers with a JC-1 detection kit. Fe2+ content was evaluated using an iron assay kit. The section of tumor tissues was observed using hematoxylin-eosin (H&E) staining and nuclear factor erythroid 2-related factor 2 (Nrf2) expression was detected by immunohistochemistry (IHC) staining. Eriodictyol suppressed cell viability and induced cell apoptosis of CaoV3 and A2780 cells. Half maximal inhibitory concentration (IC50 ) value of CaoV3 at 24 and 48 h was (229.74 ± 5.13) µM and (38.44 ± 4.68) µM, and IC50 value of A2780 at 24 and 48 h was (248.32 ± 2.54) µM and (64.28 ± 3.19) µM. Fe2+ content and reactive oxygen species production were increased and protein levels of SLC7A11 and GPX4 were decreased by eriodictyol. Besides, eriodictyol reduced the ratio of JC-1 fluorescence ratio, glutathione and malondialdehyde contents but elevated Cytochrome C level. Nrf2 phosphorylation were obviously downregulated by eriodictyol. Finally, eriodictyol suppressed tumor growth, aggravated mitochondrial dysfunction and downregulated Nrf2 expression in tumor tissue in mice. Eriodictyol regulated ferroptosis, mitochondrial dysfunction and cell viability via Nrf2/HO-1/NQO1 signaling pathway in ovarian cancer.

Effect and mechanism of eriodictyol on non-alcoholic fatty liver disease by regulating MAPK and Nrf2/HO-1 signaling pathway / 中国药房

OBJECTIVE To study the effect and potential mechanism of eriodictyol on non-alcoholic fatty liver disease （NAFLD）. METHODS Sixteen C57BL/6J mice were randomly divided into control group， NAFLD model group， and eriodictyol low-dose and high-dose groups （50， 100 mg/kg）， with 4 mice in each group. Except for control group， the other groups were fed with high fat diet to induce NAFLD model. After four weeks of preprocessing， they were given relevant medicine intraperitoneally （0.01 mL/g）， once a day， for 6 consecutive weeks. The body weight and liver weight of mice were measured， and the pathological damage of liver tissue in mice was observed. The levels of aspartate aminotransferase （AST）， alanine aminotransferase（ALT）， and triglycerides （TG） in serum， as well as the protein expressions of nuclear factor-erythroid 2-related factor 2 （Nrf2） and heme oxygenase-1 （HO-1） in liver tissue were determined. In vitro NAFLD model was established by using 0.5 mmol/L oleic acid （OA） in HepG2 cells. Normal control group， NAFLD model group and eriodictyol low-， medium- and high-concentration groups （50， 100， 150 μmol/L） were set up. HepG2 cells in drug groups were treated with eriodictyol for 24 h at the time of modeling. The lipid deposition was observed in cells， and the levels of TG， malondialdehyde （MDA） and reactive oxygen species （ROS） as well as the phosphorylation levels of the mitogen-activated protein kinase （MAPK） signal pathway related proteins [extracellular signal-regulated kinase （ERK）， c- Jun N-terminal kinase （JNK）] and the protein expressions of Nrf2 and HO-1 were all determined. RESULTS In the in vivo experiment， compared with the NAFLD model group， the body weight， liver weight， the serum levels of AST， ALT and TG were all decreased significantly in eriodictyol low- and high-dose groups （except for serum level of AST in eriodictyol low-dose group） （P＜0.01）； liver lipid deposition was reduced significantly and the protein expressions of Nrf2 and HO-1 in liver tissues were further up-regulated （P＜0.01）. In the in vitro experiment， compared with the NAFLD model group， the lipid deposition in hepatocytes was reduced in eriodictyol low-， medium- and high-concentration groups （P＜0.01）， and the levels of ROS， MDA and TG were down-regulated （P＜0.05 or P＜0.01）； the phosphorylation levels of ERK and JNK were significantly down-regulated （P＜0.01）， while the protein expressions of Nrf2 and HO-1 were up-regulated significantly （P＜0.01）. CONCLUSIONS Eriodictyol can inhibit MAPK signaling pathway and activate Nrf2/HO-1 signaling pathway to alleviate NAFLD.

Eriodictyol Suppresses Gastric Cancer Cells via Inhibition of PI3K/AKT Pathway.

Gastric cancer (GC) is among the five most common malignancies worldwide. Traditional chemotherapy cannot efficiently treat the disease and faces the problems of side effects and chemoresistance. Polygoni orientalis Fructus (POF), with flavonoids as the main bioactive compounds, exerts anti-cancer potential. In this study, we compared the anti-GC effects of the main flavonoids from POF and investigated the anti-cancer effects of eriodictyol towards GC both in vitro and in vivo. CCK-8 assays were performed to examine the inhibitory effects of common flavonoids from POF on GC cell viability. Colony formation assays were used to determine cell proliferation after eriodictyol treatment. Cell cycle distribution was analyzed using flow cytometry. Induction of apoptosis was assessed with Annexin V/PI staining and measurement of related proteins. Anti-cancer effects in vivo were investigated using a xenograft mouse model. Potential targets of eriodictyol were clarified by network pharmacological analysis, evaluated by molecular docking, and validated with Western blotting. We found that eriodictyol exhibited the most effective inhibitory effect on cell viability of GC cells among the common flavonoids from POF including quercetin, taxifolin, and kaempferol. Eriodictyol suppressed colony formation of GC cells and induced cell apoptosis. The inhibitory effects of eriodictyol on tumor growth were also validated using a xenograft mouse model. Moreover, no obvious toxicity was identified with eriodictyol treatment. Network pharmacology analysis revealed that PI3K/AKT signaling ranked first among the anti-GC targets. The molecular docking model of eriodictyol and PI3K was constructed, and the binding energy was evaluated. Furthermore, efficient inhibition of phosphorylation and activation of PI3K/AKT by eriodictyol was validated in GC cells. Taken together, our results identify eriodictyol as the most effective anti-GC flavonoids from POF and the potential targets of eriodictyol in GC. These findings suggest that eriodictyol has the potential to be a natural source of anti-GC agents.

The effects of aurone on the yellowing of fresh-cut water chestnuts.

Yellowing is the main reason for deterioration of edible quality of fresh cut water chestnuts (FCWCs). The mechanism of aurone inhibiting the yellowing of FCWCs was studied. FCWCs were treated with aurone (0.2, 0.6 and 1.0 %). The controls yellowed completely on day 9. The treatment sample with 1.0 % aurone did not yellow on day 9. Compared to the controls, aurone (1.0 %) completely inhibited the production of eriodictyol during 9 d of storage. Aurone (1.0 %) reduced peroxidase activity of FCWCs by 23 % on day 9. The effects of aurone on naringenin concentration, polyphenol oxidase activity, phenylalanine lyase activity, number of thermophilic bacteria colonies, and number of yeasts and molds colonies of FCWCS were not significant. Aurone reduced the yellowing by decreasing the yield of eriodictyol and inhibiting POD activity. Aurone (1.0 %) can be used to inhibit the yellowing of FCWCs in practice.