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Cortex Fraxini is a traditional Chinese herb that is widely available, inexpensive, and has low toxicity. Modern pharmacological studies have demonstrated that the active metabolites in Cortex Fraxini, including esculin, esculetin, and fraxetin, exert anti-tumor activities by regulating genes and proteins involved in cancer cell proliferation, apoptosis, invasion, and migration. Additionally, these metabolites play a pivotal role in the regulation of several tumor-associated signaling pathways, including the PI3K/Akt, MAPK/ERK, JAK/STAT3, and Wnt/β-catenin pathways. Due to their pro-apoptotic and anti-proliferative properties in vitro and in vivo, Cortex Fraxini and its active metabolites may be considered as potential candidates for the treatment of tumor. The aim of this review is to highlight the anti-tumor biological activities and underlying mechanisms of action of the active metabolites of Cortex Fraxini, with a view to providing a reference for their further development and application in the treatment of tumors. [ABSTRACT FROM AUTHOR]

Abstract Objective Previous studies have shown that fraxetin has antitumor activity in a variety of tumors, but its role in acute myeloid leukemia (AML) remains unclear. In this study, we aimed to evaluate the anti-AML effect of fraxetin through cell experiments and network pharmacology analysis. Methods The inhibitory and apoptotic effects of fraxetin on AML cells were determined by CCK-8 and flow cytometry experiments. Potential targets of fraxetin and AML-related targets were screened using public databases. PPI network, GO functional enrichment and KEGG pathway enrichment analyses were performed to predict the hub targets and signaling pathways by which fraxetin alleviates AML. Molecular docking was used to determine the fraxetin binding sites on hub targets. Using the GEPIA database, the expression of hub targets was analyzed in relation to the overall survival of AML patients. Results Cell experiments showed that fraxetin inhibits AML cell proliferation and induces apoptosis. To explore the potential mechanism of fraxetin, 29 shared targets of fraxetin and AML were obtained through screening online public databases. Among them, AKT1, TNF, SRC, etc., are related to AML cell apoptosis. The expression levels of SRC, NOS3, VAV1, LYN, and PTGS1 were associated with the overall survival of AML patients (p value

Simple Summary: Tilapia is the second-most-farmed fish worldwide which plays a critical role in providing high-quality proteins to human. However, infections caused by S. agalactiae result in huge economic losses. Moreover, the spreads of antibiotic resistance restrict the use of antibiotics in treating S. agalactiae infections. Here, we tried to develop anti-S. agalactiae drugs by inhibiting SrtA to overcome infections caused by resistant bacterial strains. Sortase A (SrtA) is responsible for anchoring surface proteins to the cell wall, and has been identified as a promising target developing anti-infective drugs of Gram-positive bacteria. The aim of the study was to identify inhibitors of Streptococcus agalactiae (S. agalactiae) SrtA from natural compounds to overcome the spread of antibiotic resistance in aquaculture. Here, we found that the MIC of fraxetin against S. agalactiae was higher than 256 μg/mL, indicating that fraxetin had no anti- S. agalactiae activity. But fraxetin could dose-dependently decrease the activity of SrtA in vitro at concentrations ranging between 4–32 μg/mL by a fluorescence resonance energy transfer (FRET) assay. Moreover, the inhibition of SrtA by fraxetin decreased the anchoring of surface proteins with the LPXTG motif to the cell wall by detecting the immunofluorescence change of serine-rich repeat protein 1 (Srr1) on the bacterial cell surface. The results of fibronectin binding and cell adhesion assays indicated that fraxetin could significantly decrease the adhesion ability of S. agalactiae in a dose-dependent manner. The results were further proven by immunofluorescence staining. Animal challenge results showed that treatment with fraxetin could reduce the mortality of tilapia infected with S. agalactiae to 46.67%, indicating that fraxetin could provide a significant amount of protection to tilapia by inactivating SrtA. Taken together, these findings provided a novel inhibitor of S. agalactiae SrtA and a promising candidate for treating S. agalactiae infections in aquaculture. [ABSTRACT FROM AUTHOR]

Objective: To explore the pharmacological mechanism of the effect of fraxetin in treating acute myeloid leukemia (AML) by the network pharmacology method combined with experimental validation. Methods: The targets of fraxetin were identified through Swisstarget prediction, PhammerMap, and CTDBASE. Disease-related targets of AML were explored using GeneCards and DisGenet databases, and the intersected targets were analyzed in the String website to construct a protein-protein interaction (PPI) network. Subsequently, gene ontology (GO) functional enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment were conducted using the DAVID database. Molecular docking of core proteins with drugs was performed using Auto Dock Vina software. Finally, the effect of fraxetin on AML was evaluated by in vitro experiments. The effect of fraxetin on AML cell proliferation was assessed by CCK8, the effect of fraxetin on AML cell apoptosis was assessed by flow cytometry, and the expression of relevant protein targets was detected by Western blotting to evaluate the anti-AML effect of fraxetin. Results: In this study, fraxetin exerts its effect against AML through 101 intersecting genes. The pathway enrichment analysis revealed that the pharmacological effects of fraxetin on AML were related to the Adenosine 5‘-monophosphate (AMP)-activated protein kinase （AMPK） signaling pathway, and the molecular docking results indicated that fraxetin had an excellent binding affinity to both the core target and AMPK. In vitro experiments have demonstrated that fraxetin inhibited the proliferation and induced apoptosis of THP1 and HL60 cells, and the western blotting results indicated that the p-AMPK of the fraxetin intervention group was significantly changed in a dose-dependent manner. Conclusion: Fraxetin may modulate the AMPK signal pathway by interactine with the core target, thereby potentially therapeutic effect on AML.

Cisplatin‐induced kidney injury (CKI) is a common complication of chemotherapy. Fraxetin, derived from Fraxinus bungeana A. DC. bark, has antioxidant, anti‐inflammatory, and anti‐fibrotic effects. This study aims to investigate fraxetin's effects on CKI and its underlying mechanism in vivo and in vitro. Tubular epithelial cells (TECs) and mice were exposed to cisplatin with and without fraxetin preconditioning assess fraxetin's role in CKI. TECs autophagy was observed using transmission electron microscopy. Apoptosis levels in animal tissues were measured using TUNEL staining. The protective mechanism of fraxetin was explored through pharmacological and genetic regulation of mTORC1. Molecular docking was used to identify potential binding sites between fraxetin and mTORC1. The results indicated that fraxetin pretreatment reduced cisplatin‐induced kidney injury in a time‐ and concentration‐dependent way. Fraxetin also decreased autophagy in TECs, as observed through electron microscopy. Tissue staining confirmed that fraxetin pretreatment significantly reduced cisplatin‐induced apoptosis. Inhibition of mTORC1 using rapamycin or siRNA reversed the protective effects of fraxetin on apoptosis and autophagy in cisplatin‐treated TECs, while activation of mTORC1 enhanced fraxetin's protective effect. Molecular docking analysis revealed that fraxetin can bind to HEAT‐repeats binding site on mTORC1 protein. In summary, fraxetin pretreatment alleviates CKI by antagonizing autophagy and apoptosis via mTORC1 activation. This provides evidence for the potential therapeutic application of fraxetin in CKI. [ABSTRACT FROM AUTHOR]

Fraxetin, a natural compound extracted from the Chinese herb Cortex Fraxini, is reported to boast extensive antitumor properties in various cancers. However, whether fraxetin exhibited an anticancer effect on bladder cancer remains unknown. In this study, cell counting kit‐8 was utilized to detect cell viability. Flow cytometry analysis was performed for cell apoptosis analysis. Western blot analysis and real‐time PCR were used to ascertain gene expression analysis. A mouse bladder cancer xenograft model was established and subjected to fraxetin treatment. Fraxetin reduced the viability of bladder cancer cells, induced apoptosis in vitro, and inhibited the growth of bladder cancer in vivo. Fraxetin inhibited the Akt pathway in J82 cells. In conclusion, the growth inhibitory properties of fraxetin against bladder cancer may be mediated via an Akt inhibitory effect and cell apoptosis promotion. [ABSTRACT FROM AUTHOR]

Introduction: Idiopathic pulmonary fibrosis (IPF) is a debilitating lung condition with few available treatments. The early driver of wound repair that contributes to IPF has been extensively identified as repetitive alveolar epithelial damage. According to recent reports, IPF is linked to ferroptosis, a unique type of cell death characterized by a fatal buildup of iron and lipid peroxidation. Objective and method: There is little information on epithelial cells that induce pulmonary fibrosis by going through ferroptosis. In this study, we used bleomycin (BLM) to examine the impact of ferroptosis on IPF in mouse lung epithelial cells (MLE-12). Results: We discovered that BLM increases ferroptosis in MLE-12. Additionally, we found that NCOA4 is overexpressed and plays a key role in the ferroptosis of epithelial cells throughout the IPF process. Using Molecular docking, we found that Fraxetin, a natural component extracted from Fraxinus rhynchophylla, formed a stable binding to NCOA4. In vitro investigations showed that Fraxetin administration greatly decreased ferroptosis and NCOA4 expression, which in turn lowered the release of inflammatory cytokines. Conclusion: Fraxetin treatment significantly alleviated BLM-induced lung inflammation and fibrosis. Our findings imply that fraxetin possesses inhibitory roles in ferroptosis and can be a potential drug against IPF. [ABSTRACT FROM AUTHOR]

Ulcerative colitis (UC) is one of the primary inflammatory bowel diseases (IBDs) and causes a serious threat to human public health around the world. Currently, there are no proven safe and effective treatment options to treat UC. Fraxetin (Fxt) is a widely recognized antioxidant and anti-inflammatory legume derived from ash bark. In the present study, we investigated the protective effect and mechanism of Fxt on UC. Our results showed that Fxt significantly attenuated the body weight, colon length reduction, tissue damage, and disease activity index induced by dextran sodium sulphate (DSS). Moreover, the DSS-induced activation of the NF-κB pathway and NLRP3 inflammasomes was inhibited, and the inflammatory response was reduced. Fxt restored gut barrier function by increasing the number of goblet cells and the levels of tight junction proteins (ZO-1 and occludin). In addition, Fxt can alter the intestinal microbiota by enhancing the diversity of the microbiota, increasing the relative abundance of beneficial bacteria and inhibiting the growth of harmful bacteria. These results revealed that Fxt alleviates DSS-induced colitis by modulating the inflammatory response, enhancing epithelial barrier integrity and regulating the gut microbiota. This study may provide a scientific basis for the potential therapeutic effect of Fxt in the prevention of colitis and other related diseases.

ObjectiveUsing transcriptome sequencing to screen the differentially expressed genes between the synovial tissue of rats with knee osteoarthritis (KOA) induced by monosodium iodoacetate (MIA) and that of normal rats, and then screen the target of fraxetin in the treatment of synovitis.MethodsSD rats were divided into KOA group and the negative control (NC) group. Rat right knee KOA model was prepared by MIA knee joint injection in KOA group and none treatments in NC group. Four weeks after modeling, the right knee synovial tissue of rats in each group was taken for transcriptome sequencing. Then the differential gene expression analysis, GO enrichment analysis, KEGG function enrichment analysis and PPI protein network interaction analysis were performed. The synovial macrophage Raw264.7 cells were divided into the control group, lipopolysaccharide (LPS) intervention group and LPS+60 μmol/L fraxetin intervention group, then RNA-sequencing results were verified by qRT-PCR in the three groups.ResultsThe results of differential gene-expression analysis showed that there were 1 730 up-regulated genes and 1 546 down-regulated genes in the KOA group compared with the control group, among which the significantly up-regulated genes were mmp12, Acod1, Acan, Col2a1, Atp6v0d2 (|log2(FoldChange)|≥1, adjusted P

Sortase A (SrtA) is responsible for anchoring surface proteins to the cell wall, and has been identified as a promising target developing anti-infective drugs of Gram-positive bacteria. The aim of the study was to identify inhibitors of Streptococcus agalactiae (S. agalactiae) SrtA from natural compounds to overcome the spread of antibiotic resistance in aquaculture. Here, we found that the MIC of fraxetin against S. agalactiae was higher than 256 μg/mL, indicating that fraxetin had no anti- S. agalactiae activity. But fraxetin could dose-dependently decrease the activity of SrtA in vitro at concentrations ranging between 4–32 μg/mL by a fluorescence resonance energy transfer (FRET) assay. Moreover, the inhibition of SrtA by fraxetin decreased the anchoring of surface proteins with the LPXTG motif to the cell wall by detecting the immunofluorescence change of serine-rich repeat protein 1 (Srr1) on the bacterial cell surface. The results of fibronectin binding and cell adhesion assays indicated that fraxetin could significantly decrease the adhesion ability of S. agalactiae in a dose-dependent manner. The results were further proven by immunofluorescence staining. Animal challenge results showed that treatment with fraxetin could reduce the mortality of tilapia infected with S. agalactiae to 46.67%, indicating that fraxetin could provide a significant amount of protection to tilapia by inactivating SrtA. Taken together, these findings provided a novel inhibitor of S. agalactiae SrtA and a promising candidate for treating S. agalactiae infections in aquaculture.

Little therapeutic effect can be exerted on malignant ovarian cancer at the terminal period. Traditional Chinese medicine (TCM) has been a potential way for the treatment of various diseases. In this research, we probed into the potential curative effect of Fraxetin (FXT), a TCM monomer, on ovarian cancer. Ovarian cancer cells were treated with FXT at different concentrations for 12 h, or pretreated by 0.5 μM of colivelin, a STAT3 activator, for 1 h and then treated with 80 μM of FXT for 12 h. The viability of ovarian cancer cells was measured by MTT assay, and the cell colony number was counted after colony formation assay. Transwell assay was conducted for investigating the relationship between the FXT at different concentrations and the invasion as well as migration rates of ovarian cancer cells. The expressions of epithelial-to-mesenchymal transition (EMT)-associated markers and TLR4/STAT3 signaling pathway-related proteins in ovarian cancer cells after the treatment of FXT were measured by western blot. FXT inhibited the viability, invasion, migration, and proliferation of SKOV3 and SW626 cells and suppressed EMT, but colivelin reversed the impacts of FXT. FXT also suppressed the expressions of N-cadherin, snail, vimentin, TLR4, phosphorylated (P)-STAT3, cyclin D1, and C-myc, whilst promoting that of E-cadherin by inhibiting the activation of TLR4/STAT3 signaling pathway. FXT exerts a therapeutic effect on ovarian cancer by repressing the TLR4/STAT3 signaling pathway. With the accumulating concentrations of FXT, the therapeutic effect becomes more and more obvious. [ABSTRACT FROM AUTHOR]

Purpose: Chronic unpredictable stress (CUS) induces long-term neuronal and synaptic plasticity with a neurohormonal disbalance leading to the development of co-existing anxiety, depression, and cognitive decline. The side effects and delayed onset of current clinically used antidepressants has prompted a quest for antidepressants with minimum drawbacks. Fraxetin is a natural coumarin derivative with documented antioxidant and neuroprotective activity though its effects on stress are unknown. This study therefore aimed to investigate any possible acute effect of fraxetin in behavioral tests including a CUS paradigm in correlation with brain regional neurochemical changes. Methods: Mice were subjected to a series of mild stressors for 14 days to induce CUS. Furthermore, behavioral performance in the open field test, forced swim test (FST), Y-maze and elevated plus-maze were evaluated. Postmortem frontal cortical, hippocampal and striatal tissues were analyzed via high-performance liquid chromatography (HPLC) for neurochemical changes. Result: Acute administration of fraxetin (20–60 mg/kg, orally) decreased depression-like behavior in the FST and behavioral anxiety in both the open field test and elevated plus-maze. Memory deficits induced during the CUS paradigm were markedly improved as reflected by enhanced Y maze performance. Concurrent biochemical and neurochemical analyses revealed that only the two higher fraxetin doses decreased elevated serum corticosterone levels while diminished serotonin levels in the frontal cortex, striatum and hippocampus were reversed, though noradrenaline was only raised in the striatum. Concomitantly, dopamine levels were restored by fraxetin at the highest dose exclusively in the frontal cortex. Conclusion: Acute treatment with fraxetin attenuated CUS-induced behavioral deficits, ameliorated the increased corticosterone level and restored altered regional neurotransmitter levels and this may indicate a potential application of fraxetin in the management of anxiety and depression modeled by CUS. However, further studies are warranted regarding the chronic effects of fraxetin behaviorally and neurochemically. [ABSTRACT FROM AUTHOR]

Purpose: Chronic unpredictable stress (CUS) induces long-term neuronal and synaptic plasticity with a neurohormonal disbalance leading to the development of co-existing anxiety, depression, and cognitive decline. The side effects and delayed onset of current clinically used antidepressants has prompted a quest for antidepressants with minimum drawbacks. Fraxetin is a natural coumarin derivative with documented antioxidant and neuroprotective activity though its effects on stress are unknown. This study therefore aimed to investigate any possible acute effect of fraxetin in behavioral tests including a CUS paradigm in correlation with brain regional neurochemical changes.Methods: Mice were subjected to a series of mild stressors for 14 days to induce CUS. Furthermore, behavioral performance in the open field test, forced swim test (FST), Y-maze and elevated plus-maze were evaluated. Postmortem frontal cortical, hippocampal and striatal tissues were analyzed via high-performance liquid chromatography (HPLC) for neurochemical changes.Result: Acute administration of fraxetin (20–60 mg/kg, orally) decreased depression-like behavior in the FST and behavioral anxiety in both the open field test and elevated plus-maze. Memory deficits induced during the CUS paradigm were markedly improved as reflected by enhanced Y maze performance. Concurrent biochemical and neurochemical analyses revealed that only the two higher fraxetin doses decreased elevated serum corticosterone levels while diminished serotonin levels in the frontal cortex, striatum and hippocampus were reversed, though noradrenaline was only raised in the striatum. Concomitantly, dopamine levels were restored by fraxetin at the highest dose exclusively in the frontal cortex.Conclusion: Acute treatment with fraxetin attenuated CUS-induced behavioral deficits, ameliorated the increased corticosterone level and restored altered regional neurotransmitter levels and this may indicate a potential application of fraxetin in the management of anxiety and depression modeled by CUS. However, further studies are warranted regarding the chronic effects of fraxetin behaviorally and neurochemically.

Malignant melanoma is a skin cancer characterized by rapid development, poor prognosis and high mortality. Due to the frequent drug resistance and/or early metastases in melanoma, new therapeutic methods are urgently needed. The study aimed at assessing the cytotoxic and antiproliferative effects of scoparone and fraxetin in vitro, when used alone and in combination with three cytostatics: cisplatin, mitoxantrone, and docetaxel in four human melanoma cell lines. Our experiments showed that scoparone in the concentration range tested up to 200 µM had no significant effect on the viability of human malignant melanoma (therefore, it was not possible to evaluate it in combination with other cytostatics), while fraxetin inhibited cell proliferation with IC50 doses in the range of 32.42–73.16 µM, depending on the cell line. Isobolographic analysis allowed for the assessment of the interactions between the studied compounds. Importantly, fraxetin was not cytotoxic to normal keratinocytes (HaCaT) and melanocytes (HEMa-LP), although it slightly inhibited their viability at high concentrations. The combination of fraxetin with cisplatin and mitoxantrone showed the additive interaction, which seems to be a promising direction in melanoma therapy. Unfortunately, the combination of fraxetin with docetaxel may not be beneficial due to the antagonistic antiproliferative effect of both drugs used in the mixture. [ABSTRACT FROM AUTHOR]

Coumarins are generally considered to be produced by natural plants. Fungi have been reported to produce coumarins, but their biosynthetic pathways are still unknown. In this study, Fusarium oxysporum GU-7 and GU-60 were isolated from Glycyrrhiza uralensis, and their antioxidant activities were determined to be significantly different. Abundant dipeptide, phenolic acids, and the plant-derived coumarins fraxetin and scopoletin were identified in GU-7 by untargeted metabolomics, and these compounds may account for its stronger antioxidant activity compared to GU-60. Combined with metabolome and RNA sequencing analysis, we identified 24 potentially key genes involved in coumarin biosynthesis and 6 intermediate metabolites. Interestingly, the best hit of S8H, a key gene involved in hydroxylation at the C-8 position of scopoletin to yield fraxetin, belongs to a plant species. Additionally, nondestructive infection of G. uralensis seeds with GU-7 significantly improved the antioxidant activity of seedlings compared to the control group. This antioxidant activity may depend on the biological characteristics of endophytes themselves, as we observed a positive correlation between the antioxidant activity of endophytic fungi and that of their nondestructively infected seedlings. [ABSTRACT FROM AUTHOR]

Objective Using transcriptome sequencing to screen the differentially expressed genes between the synovial tissue of rats with knee osteoarthritis (KOA) induced by monosodium iodoacetate (MIA) and that of normal rats, and then screen the target of fraxetin in the treatment of synovitis. Methods SD rats were divided into KOA group and the negative control (NC) group. Rat right knee KOA model was prepared by MIA knee joint injection in KOA group and none treatments in NC group. Four weeks after modeling, the right knee synovial tissue of rats in each group was taken for transcriptome sequencing. Then the differential gene expression analysis, GO enrichment analysis, KEGG function enrichment analysis and PPI protein network interaction analysis were performed. The synovial macrophage Raw264.7 cells were divided into the control group, lipopolysaccharide (LPS) intervention group and LPS+60 μmol/L fraxetin intervention group, then RNA-sequencing results were verified by qRT-PCR in the three groups. Results The results of differential gene-expression analysis showed that there were 1 730 up-regulated genes and 1 546 down-regulated genes in the KOA group compared with the control group, among which the significantly up-regulated genes were mmp12, Acod1, Acan, Col2a1, Atp6v0d2 (|log2(FoldChange)| ≥1, adjusted P<0.01). KEGG cluster analysis and GO cluster analysis showed that differential genes were mainly involved in the regulation of inflammation and immune metabolism, such as tricarboxylic acid cycle and mitochondrial function. The expressions of Acod1 and Atp6v0d2 in Raw264.7 cells after LPS intervention were significantly higher. Compared with the LPS intervention group, the expression level of Atp6v0d2 in Raw264.7 cells after LPS+fraxetin combined intervention was significantly lower. Conclusion After modeling KOA induced by MIA, macrophage-related genes mmp12, Acod1 and Atp6v0D2, which mediate inflammation and immune metabolism, were highly expressed in the synovial tissue of rats, suggesting that there might be immune metabolism changes mediated by synovial macrophages during the occurrence and development of KOA. The increased expression of Acod1 and Atp6v0d2 in macrophages Raw264.7 after LPS intervention can preliminarily confirm this result. Among them, Atp6v0d2 may be a potential target of fraxetin in the treatment of synovitis, which provides a new idea for KOA treatment. [ABSTRACT FROM AUTHOR]

ABSTRACT The increasingly serious problem of bacterial drug resistance has led to the development of antivirulence agents. The Salmonella enterica serovar Typhimurium Salmonella pathogenicity island (SPI)-encoded type III secretion system (T3SS) and its effector proteins are important virulence factors for S. Typhimurium invasion and replication in host cells and for antivirulence drug screening. Fraxetin is isolated from Fraxinus spp. Extensive studies have reported its multiple pharmacological activities. However, it remains to be elucidated whether fraxetin affects the function of the S. Typhimurium T3SS. In this study, the anti-infection mechanism of fraxetin on S. Typhimurium and its T3SS was investigated. Fraxetin inhibited the S. Typhimurium invasion of HeLa cells without affecting the growth of bacteria in vitro. Further findings on the mechanism showed that fraxetin had an inhibitory effect on the S. Typhimurium T3SS by inhibiting the transcription of the pathogenesis-related SPI-1 transcriptional activator genes hilD, hilC, and rtsA. Animal experiments showed that fraxetin treatment protected mice against S. Typhimurium infection. Collectively, we provide the first demonstration that fraxetin may serve as an effective T3SS inhibitor for the development of treatments for Salmonella infection. IMPORTANCE The increasingly serious problem of bacterial antibiotic resistance limits the clinical application of antibiotics, which increases the need for the development of antivirulence agents. The type III secretion system (T3SS) plays a critical role in host cell invasion and pathogenesis of Salmonella and becomes a popular target for antivirulence agents screening. Our study found, for the first time, that fraxetin inhibited S. Typhimurium invasion by inhibiting the transcription of genes in a feed-forward regulatory loop. Further in vivo testing showed that fraxetin decreased bacterial burdens in the spleen and liver of S. Typhimurium-infected mice and improved survival outcomes in an in vivo mouse model of S. Typhimurium infection. Collectively, these results demonstrate that fraxetin inhibits S. Typhimurium infection by targeting the T3SS and may serve as a potential agent for the treatment of S. Typhimurium infection.

The common term for cis-o-hydroxy cinnamic acid lactones, which all possess the fundamental structure of the benzo a-pyranone mother nucleus, is coumarins. Especially in Umbelliferae, Rutaceae, Daphne, and Oleaceae, coumarins are extensively dispersed in the roots, stems, leaves, flowers, fruits, and seeds of higher plants. A few coumarins are also detected in certain microbes and mammals. Certain coumarin molecules may also be synthesized artificially. We have discussed the probable mechanisms behind coumarins' anti-diabetic benefits. Numerous in vivo and in vitro studies show that coumarins may treat diabetes by reducing inflammation and oxidative stress, enhancing pancreatic function, and reversing aberrant insulin signaling. As a result, they are useful and need further study and development. In conclusion, it is clear that coumarins have a range of biochemical and pharmacological characteristics, some of which have potential therapeutic value that may be useful against diabetes and its consequences. To sum up, improvements in the area have allowed for the isolation or chemical design of novel advantageous compounds with coumarin cores as candidates against diabetes and its consequences; nevertheless, additional study is necessary before safe and effective coumarin medications are employed in the clinic. [ABSTRACT FROM AUTHOR]

Recent studies have identified obesity as one of the world's most serious chronic disorders. Adipogenesis, in which preadipocytes are differentiated into mature adipocytes, has a decisive role in establishing the number of adipocytes and determining the lipid storage capacity of adipose tissue and fat mass in adults. Fat accumulation in obesity is implicated with elevated oxidative stress in adipocytes induced by reactive oxygen species (ROS). Adipogenesis regulation by inhibiting adipogenic differentiation and ROS production has been selected as the strategy to treat obesity. The conventional anti-obesity drugs allowed by the U.S. Food and Drug Administration have severe adverse effects. Therefore, various natural products have been developed as a solution for obesity, suppressing adipogenic differentiation. Fraxetin is a major component extracted from the stem barks of Fraxinus rhynchophylla, with various bioactivities, including anti-inflammatory, anticancer, antioxidant, and antibacterial functions. However, the effect of fraxetin on adipogenesis is still not clearly understood. We studied the pharmacological functions of fraxetin in suppressing lipid accumulation and its underlying molecular mechanisms involving 3T3-L1 preadipocytes. Moreover, increased ROS production induced by a mixture of insulin, dexamethasone, and 3-isobutylmethylxanthine (MDI) in 3T3-L1 was attenuated by fraxetin during adipogenesis. These effects were regulated by mitogen-activated protein kinase (MAPK) signaling pathways. Therefore, our findings imply that fraxetin possesses inhibitory roles in adipogenesis and can be a potential anti-obesity drug. [ABSTRACT FROM AUTHOR]

Cortex Fraxini is a traditional Chinese herb that is widely available, inexpensive, and has low toxicity. Modern pharmacological studies have demonstrated that the active metabolites in Cortex Fraxini, including esculin, esculetin, and fraxetin, exert anti-tumor activities by regulating genes and proteins involved in cancer cell proliferation, apoptosis, invasion, and migration. Additionally, these metabolites play a pivotal role in the regulation of several tumor-associated signaling pathways, including the PI3K/Akt, MAPK/ERK, JAK/STAT3, and Wnt/β-catenin pathways. Due to their pro-apoptotic and anti-proliferative properties in vitro and in vivo , Cortex Fraxini and its active metabolites may be considered as potential candidates for the treatment of tumor. The aim of this review is to highlight the anti-tumor biological activities and underlying mechanisms of action of the active metabolites of Cortex Fraxini, with a view to providing a reference for their further development and application in the treatment of tumors., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Cai, Cai, Feng and Zhu.)

Fraxetin has antioxidant, anti-inflammation and neuroprotective functions, however, its role in ischemic stroke is still vague. Herein, this study delves into the underlying mechanism. Ischemia and reperfusion operation were performed to establish the cerebral stroke rat models. The brain functions were evaluated with neurological score. The brain infarcted volume in fraxetin group was measured by 2,3,5-triphenyltetrazolium chloride staining. The blood-brain barrier permeability, CD34 enrichment, and the brain water content were measured by Evans blue staining, immunofluorescence staining, and wet-dry method, respectively. Real-time quantitative polymerase chain reaction (RT-qPCR) and western blot (WB) were applied to examine the levels of angiogenesis- and PI3K/Akt pathway-related factors. MTT and tube formation assays were used to measure the viability and tube formation of HUVECs. Fraxetin decreased the brain injury-related neurological score, brain infarction, and cerebral edema and maintained blood-brain barrier permeability, whereas it promoted the angiogenesis in ischemia-damaged brain via enhancing CD34 enrichment, the expressions of VEGF, Ang-1, Tie-2, and CD-31, viability of HUVECs, as well as activating the phosphorylation of PI3K and Akt. Importantly, wortmannin (a specific PI3K inhibitor) impeded the fraxetin-induced cell viability, angiogenesis, and phosphorylation of Akt and PI3K in HUVECs. Fraxetin has protective effects on the brain ischemia-reperfusion injury and promotes angiogenesis for cerebral repair via phosphorylation of PI3K and Akt. [ABSTRACT FROM AUTHOR]

Fraxetin (FXT) exerts anticancer function in multiple cancers, but its function on glioma was ill‐defined. This article expounded the mechanism by which FXT exerts an anticancer effect in glioma. The effect of gradient concentration of FXT on the viability of glioma cell lines was determined by cell counting kit 8. Effects of FXT on proliferation, apoptosis, and cell cycle in glioma cell lines were determined by colony formation assay, flow cytometry, and Hoechst 33342 staining. Expressions of apoptosis‐related gene, cycle‐related gene, and glioma‐related miRNAs after FXT (25 and 50 μmol/L) treatment were determined by quantitative reverse transcription polymerase chain reaction and western blot as needed. After miR‐21‐3p overexpression, cell viability and apoptosis of glioma cell lines treated with FXT (50 μmol/L) were tested again. Although 1 μmol/L FXT had no significant effect on cell viability, 5, 10, 25, and 50 μmol/L FXT suppressed cell viability in a concentration‐dependent manner. FXT inhibited proliferation, promoted apoptosis, and induced cell cycle arrest in G0/G1 phase in glioma cell lines. These effects may be achieved by elevated expressions of Bax and cleaved caspase‐3 and diminished expressions of Bcl‐2, Bcl‐XL, cyclin E1, cyclin D1, and cyclin‐dependent kinase‐6. FXT attenuated the contents of miR‐21‐3p and miR‐455‐3p, and escalated the contents of miR‐124‐3p and miR‐7‐5p. The regulation of FXT on cell viability, proliferation and apoptosis was reversed by miR‐21‐3p overexpression. FXT suppressed the development of glioma cells by downregulating miR‐21‐3p. [ABSTRACT FROM AUTHOR]

Isoflurane, a common volatile anesthetic, has been widely used to provide general anesthesia in operations. However, exposure to isoflurane may cause widespread neurotoxicity in the developing animal brain. Fraxetin, a natural coumarin derivative extracted from the bark of Fraxinus rhynchophylla, possesses versatile pharmacological properties including anti‐oxidative, anti‐inflammatory, and neuroprotective effects. However, the effect and action mechanism of fraxetin on neurotoxicity induced by isoflurane are unknown. Reactive oxygen species (ROS) generation, cell viability, lactate dehydrogenase (LDH) release, and apoptosis were estimated by 2′,7′‐dichlorofluorescin‐diacetate (DCFH‐DA) staining, MTT, LDH release, and terminal deoxynucleotidyl transferase‐mediated deoxyuridine triphosphate nick end‐labeling (TUNEL) staining assays, respectively. The protein levels of light chain 3 (LC3)‐I, LC3‐II, p62, protein kinase B (Akt), and phosphorylated Akt (p‐Akt) were detected by western blot analysis. Isoflurane induced ROS, LDH release, apoptosis, and autophagy, but inhibited the viability in HT22 cells, which were overturned by fraxetin or ROS scavenger N‐acetyl‐L‐cysteine. Fraxetin suppressed isoflurane‐induced PI3K/Akt inactivation in HT22 cells. PI3K/Akt inactivation by LY294002 resisted the effects of fraxetin on isoflurane‐induced autophagy and autophagy‐modulated neurotoxicity in HT22 cells. In conclusion, fraxetin suppressed ROS‐dependent autophagy by activating the PI3K/Akt pathway to inhibit isoflurane‐induced neurotoxicity in hippocampal neuronal cells. Exposure to isoflurane may cause neurotoxicity. Fraxetin possesses neuroprotective effects. However, the effects and mechanisms of fraxetin on isoflurane‐induced neurotoxicity are unknown. We found that fraxetin or reactive oxygen species (ROS) scavenger N‐acetyl‐L‐cysteine overturned isoflurane‐induced neurotoxicity and autophagy. Fraxetin suppressed isoflurane‐induced PI3K/Akt inactivation. PI3K/Akt inactivation by LY294002 resisted the effects of fraxetin on isoflurane‐induced autophagy and autophagy‐modulated neurotoxicity in HT22 cells. Summarily, fraxetin suppressed ROS‐dependent autophagy by activating the PI3K/Akt pathway to inhibit isoflurane‐induced neurotoxicity. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a disease characterized by degeneration of the joint complex due to cartilage destruction. Fraxetin, a widely used and studied coumarin compound extracted from a traditional Chinese herb (Qin Pi), has shown anti-inflammatory and antioxidant properties, but its effects on OA have not been studied. In the present study, western blotting, immunofluorescence, and terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) were used to evaluate the effects of fraxetin on IL-1β-induced apoptotic activity, inflammatory responses, and catabolism in rat chondrocytes. The results showed that fraxetin prevented IL-1β-induced apoptosis of chondrocytes and inhibited inflammatory mediator release by regulating the Toll-like receptor 4 (TLR4)/myeloid differentiation primary response 88 (MyD88)/nuclear factor (NF)-κB pathway in chondrocytes. Additionally, fraxetin suppressed the upregulation of matrix metalloproteinase 13 (MMP13) and degradation of collagen II in the extracellular matrix (ECM). Moreover, the effects of fraxetin in vivo were assessed in a monosodium iodoacetate (MIA)-induced rat model of OA using hematoxylin and eosin (H&E) and Safranin O-fast green staining and magnetic resonance imaging (MRI). The results showed that fraxetin protected the cartilage against destruction. In conclusion, fraxetin could be a potential therapeutic for OA.

Objective: To explore the pharmacological mechanism of the effect of fraxetin in treating acute myeloid leukemia (AML) by the network pharmacology method combined with experimental validation., Methods: The targets of fraxetin were identified through Swisstarget prediction, PhammerMap, and CTDBASE. Disease-related targets of AML were explored using GeneCards and DisGenet databases, and the intersected targets were analyzed in the String website to construct a protein-protein interaction (PPI) network. Subsequently, gene ontology (GO) functional enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment were conducted using the DAVID database. Molecular docking of core proteins with drugs was performed using Auto Dock Vina software. Finally, the effect of fraxetin on AML was evaluated by in vitro experiments. The effect of fraxetin on AML cell proliferation was assessed by CCK8, the effect of fraxetin on AML cell apoptosis was assessed by flow cytometry, and the expression of relevant protein targets was detected by Western blotting to evaluate the anti-AML effect of fraxetin., Results: In this study, fraxetin exerts its effect against AML through 101 intersecting genes. The pathway enrichment analysis revealed that the pharmacological effects of fraxetin on AML were related to the Adenosine 5'-monophosphate (AMP)-activated protein kinase （AMPK） signaling pathway, and the molecular docking results indicated that fraxetin had an excellent binding affinity to both the core target and AMPK. In vitro experiments have demonstrated that fraxetin inhibited the proliferation and induced apoptosis of THP1 and HL60 cells, and the western blotting results indicated that the p -AMPK of the fraxetin intervention group was significantly changed in a dose-dependent manner., Conclusion: Fraxetin may modulate the AMPK signal pathway by interactine with the core target, thereby potentially therapeutic effect on AML., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Fraxetin is a bioactive molecule present in various natural plants, especially Cortex Fraxini. Evidenced outcomes in phytochemical and biological analyses for this agent are now available in the literature, but an insightful review is yet unknown. The goal of the current research is to offer a panoramic illustration of natural observation, biosynthesis, synthesis, pharmacology, and pharmacokinetics for fraxetin. Esculetin and ferulic acid acted as precursors in the enzymatic biosynthetic route, whereas fraxetin could be easily synthesized from simple phenols. A great deal of interest was obtained in using this molecule for pharmacological targets. Herein, its pharmacological value included anticancer, antioxidative, anti-inflammatory, antidiabetic, antiobesity, and antimicrobial activities, as well as the protection of the liver, neurons, heart, bone, lung, kidney, and others. Anticancer activity may involve the inhibition of proliferation, invasion, and migration, together with apoptotic induction. Health benefits from this molecule were deduced from its ability to suppress cytokines and protect the immune syndrome. Various signaling pathways, such as Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3), phosphoinositide 3 kinase (PI3K)/protein kinase B (Akt), nuclear factor kappa B (NF-κB)/NLRP3, Akt/AMPK, have been proposed for in vitro and in vivo mechanisms of action. Fraxetin is highly distributed to rat plasma and several organs. However, more pharmacokinetic studies to improve its bioavailability are needed since its solubility in water is still limited., (© 2024 Deutsche Pharmazeutische Gesellschaft.)

Malignant melanoma is a skin cancer characterized by rapid development, poor prognosis and high mortality. Due to the frequent drug resistance and/or early metastases in melanoma, new therapeutic methods are urgently needed. The study aimed at assessing the cytotoxic and antiproliferative effects of scoparone and fraxetin in vitro, when used alone and in combination with three cytostatics: cisplatin, mitoxantrone, and docetaxel in four human melanoma cell lines. Our experiments showed that scoparone in the concentration range tested up to 200 µM had no significant effect on the viability of human malignant melanoma (therefore, it was not possible to evaluate it in combination with other cytostatics), while fraxetin inhibited cell proliferation with IC50 doses in the range of 32.42–73.16 µM, depending on the cell line. Isobolographic analysis allowed for the assessment of the interactions between the studied compounds. Importantly, fraxetin was not cytotoxic to normal keratinocytes (HaCaT) and melanocytes (HEMa-LP), although it slightly inhibited their viability at high concentrations. The combination of fraxetin with cisplatin and mitoxantrone showed the additive interaction, which seems to be a promising direction in melanoma therapy. Unfortunately, the combination of fraxetin with docetaxel may not be beneficial due to the antagonistic antiproliferative effect of both drugs used in the mixture.

Recent studies have identified obesity as one of the world’s most serious chronic disorders. Adipogenesis, in which preadipocytes are differentiated into mature adipocytes, has a decisive role in establishing the number of adipocytes and determining the lipid storage capacity of adipose tissue and fat mass in adults. Fat accumulation in obesity is implicated with elevated oxidative stress in adipocytes induced by reactive oxygen species (ROS). Adipogenesis regulation by inhibiting adipogenic differentiation and ROS production has been selected as the strategy to treat obesity. The conventional anti-obesity drugs allowed by the U.S. Food and Drug Administration have severe adverse effects. Therefore, various natural products have been developed as a solution for obesity, suppressing adipogenic differentiation. Fraxetin is a major component extracted from the stem barks of Fraxinus rhynchophylla, with various bioactivities, including anti-inflammatory, anticancer, antioxidant, and antibacterial functions. However, the effect of fraxetin on adipogenesis is still not clearly understood. We studied the pharmacological functions of fraxetin in suppressing lipid accumulation and its underlying molecular mechanisms involving 3T3-L1 preadipocytes. Moreover, increased ROS production induced by a mixture of insulin, dexamethasone, and 3-isobutylmethylxanthine (MDI) in 3T3-L1 was attenuated by fraxetin during adipogenesis. These effects were regulated by mitogen-activated protein kinase (MAPK) signaling pathways. Therefore, our findings imply that fraxetin possesses inhibitory roles in adipogenesis and can be a potential anti-obesity drug.

This study sought to improve the oral bioavailability and enhance the anti-enteritis effect of fraxetin by incorporating it into long circulating liposomes (F-LC-Lipo). The optimal formulation of F-LC-Lipo was obtained via orthogonal design. The particle size, morphology, encapsulation efficiency, stability, and anti-enteritis effect of F-LC-Lipo were evaluated. The particle size of F-LC-Lipo was 166.65 ± 8.75 nm with entrapment efficiency (EE) of 92.18 ± 0.17%. The release rate in different dissolution media (pH 1.2 HCl, DDW, and pH 7.4 PBS) was significantly higher than that of fraxetin solution. Compared with the free fraxetin solution, F-LC-Lipo increased oral bioavailability of fraxetin by 4.43 times (443%). More importantly, F-LC-Lipo could improve the levels of interleukin-1 beta (IL-1β), IL-6, malondialdehyde (MDA), superoxide dismutase (SOD), tumor necrosis factor-alpha (TNF-α), C-reactive protein (CRP), prostaglandin E2 (PEG2), and IL-10 in rats with enteritis. Overall, these results suggested that LC-Lipo may serve as a potential carrier for improving the solubility and oral bioavailability of fraxetin as well as improving its enteritis effect. [ABSTRACT FROM AUTHOR]

Herein, a series of water-soluble supramolecular inclusion complexes (ICs) probes were prepared using cyclodextrins (CDs) and fraxetin (FRA) to detect nicotine (NT) with high selectivity in vitro and in vivo. The FRA/CD ICs prepared through the saturated solution method exhibited excellent water solubility, stability, and biocompatibility. A clear host-guest inclusion model was provided by the theoretical calculations. The investigation revealed that NT was able to enter into the cavities of FRA/β-CD IC and FRA/γ-CD IC, and further formed charge transfer complexes with FRA in the CD cavities, resulting in a rapid and highly selective fluorescence-enhanced response with the lowest detection limits of 1.9 × 10 -6  M and 9.7 × 10 -7  M, and the linear response ranged from 0.02 to 0.3 mM and 0.01-0.05 mM, respectively. The IC probes showed good anti-interference performance to common interferents or different pH environments, with satisfactory reproducibility and repeatability of response to NT. Furthermore, the potentiality of the probes was confirmed through fluorescence imaging experiments using human lung cancer cells and the lung tissue of mice. This study offers a fresh perspective for detecting NT in environmental and biomedical analysis., Competing Interests: Declaration of competing interest The authors declare no competing financial interest., (Copyright © 2023. Published by Elsevier Ltd.)

Osteoarthritis (OA) is a disease characterized by degeneration of the joint complex due to cartilage destruction. Fraxetin, a widely used and studied coumarin compound extracted from a traditional Chinese herb (Qin Pi), has shown anti-inflammatory and antioxidant properties, but its effects on OA have not been studied. In the present study, western blotting, immunofluorescence, and terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) were used to evaluate the effects of fraxetin on IL-1β-induced apoptotic activity, inflammatory responses, and catabolism in rat chondrocytes. The results showed that fraxetin prevented IL-1β-induced apoptosis of chondrocytes and inhibited inflammatory mediator release by regulating the Toll-like receptor 4 (TLR4)/myeloid differentiation primary response 88 (MyD88)/nuclear factor (NF)-κB pathway in chondrocytes. Additionally, fraxetin suppressed the upregulation of matrix metalloproteinase 13 (MMP13) and degradation of collagen II in the extracellular matrix (ECM). Moreover, the effects of fraxetin in vivo were assessed in a monosodium iodoacetate (MIA)-induced rat model of OA using hematoxylin and eosin (H&E) and Safranin O-fast green staining and magnetic resonance imaging (MRI). The results showed that fraxetin protected the cartilage against destruction. In conclusion, fraxetin could be a potential therapeutic for OA. [ABSTRACT FROM AUTHOR]

Doxorubicin belongs to the class of anthracycline antibiotics that is widely used in the treatment protocols of a wide range of malignancies. The major deleterious effect of doxorubicin use is the possible occurrence of cardiotoxicity. This study aimed to delineate the possible effects of targeting oxidative stress, NLRP3 inflammasome, and autophagy by fraxetin on doxorubicin-induced cardiac dysfunction in rats. In a model of doxorubicin-induced cardiotoxicity, the effects of different doses of fraxetin were assessed by determination of biochemical, histopathological, immunohistochemical, and electron microscopic changes. Fraxetin, in a dose-dependent manner, was found to have the ability to mitigate the harmful effects of oxidative stress and inflammation on myocardial muscles with significant decrease in NLRP3 inflammasome, augmentation of autophagy, and amelioration of the apoptotic signaling pathways. In addition, fraxetin, in a dose-dependent manner, had the ability to combat the echocardiographic, histopathological, immunohistochemical, and electron microscopic changes induced by doxorubicin in cardiomyocytes. As a result, fraxetin may be put into consideration as a new adjuvant line of therapy on the way to mitigate doxorubicin-induced cardiotoxicity.

Fraxetin, a natural derivative of coumarin, is known to have anti-inflammatory, anti-oxidant, and hepatoprotective effects in multiple diseases and in liver fibrosis. Whether fraxetin exerts similar effects against renal fibrosis is unknown. In a Unilateral Ureteral Obstruction (UUO) mouse model of renal fibrosis, fraxetin decreased UUO-induced renal dysfunction with a marked reduction in renal interstitial collagen fibers as detected by Masson’s Trichrome staining. Fraxetin treatment also inhibited the expression of α-SMA, Collagen I, Collagen IV, fibronectin, N-cadherin, vimentin, phosphorylated-ERK, and increased the expression of E-cadherin in UUO mice, as shown by immunohistochemical staining and western blot analysis. In vitro studies showed that fraxetin and indoxyl sulfate had no cytotoxic effects on MES13 kidney cells, but that fraxetin significantly decreased IS-induced cell motility and decreased protein expression of α-SMA, N-cadherin, vimentin, and Collagen IV via the ERK-mediated signaling pathway. These findings provide insight into the mechanism underlying fraxetin-induced inhibition of fibrogenesis in renal tissue and suggest that fraxetin treatment may be beneficial for slowing CKD progression.

Coumarins belong to a group of secondary metabolites well known for their high biological activities including antibacterial and antifungal properties. Recently, an important role of coumarins in plant resistance to pathogens and their release into the rhizosphere upon pathogen infection was discovered. It is also well documented that coumarins play a crucial role in the Arabidopsis thaliana growth under Fe-limited conditions. However, the mechanisms underlying interplay between plant resistance, accumulation of coumarins and Fe status, remain largely unknown. In this work, we investigated the effect of both mentioned factors on the disease severity using the model system of Arabidopsis/Dickeya spp. molecular interactions. We evaluated the disease symptoms in Arabidopsis plants, wild-type Col-0 and its mutants defective in coumarin accumulation, grown in hydroponic cultures with contrasting Fe regimes and in soil mixes. Under all tested conditions, Arabidopsis plants inoculated with Dickeya solani IFB0099 strain developed more severe disease symptoms compared to lines inoculated with Dickeya dadantii 3937. We also showed that the expression of genes encoding plant stress markers were strongly affected by D. solani IFB0099 infection. Interestingly, the response of plants to D. dadantii 3937 infection was genotype-dependent in Fe-deficient hydroponic solution.

Fraxetin, a natural compound present in many dietary supplements and herbs, is useful in the treatment of acute bacillary dysentery and type 2 diabetes. Previously, several metabolic studies have revealed extensive first-pass metabolism causing formation of fraxetin-O-glucuronides (G1 and G2), resulting in poor bioavailability of fraxetin. Active transport processes play an important role in the excretion of fraxetin-O-glucuronides. Nevertheless, the transporters involved are yet to be elucidated. In this study, we aimed to determine the active efflux transporters, including breast cancer resistance protein (BCRP) and multidrug resistance-associated proteins (MRPs), involved in the excretion of fraxetin-O-glucuronides. A chemical inhibitor, MK571 (5 and 20 μM), a pan-MRP inhibitor, led to a significant decrease in excreted G1 (maximal 59.1%) and G2 levels (maximal 42.4%), whereas Ko143 (5 and 20 μM), a selective BCRP inhibitor, caused moderate downregulation of excreted G1 (maximal 29.4%) and G2 (maximal 28.5%). Furthermore, MRP3 silencing resulted in a marked decrease of excretion rates (by 29.1% for G1 and by 21.1% for G2) and of fraction metabolized (fmet; by 24.1% for G1 and by 18.6% for G2). Similar results, i.e., a significant reduction in excretion rates (by 34.8% for G1 and by 32.3% for G2) and in fmet (by 22.7% for G1 and by 23.1% for G2) were obtained when MRP4 was partially silenced. No obvious modifications in the excretion rates, intracellular levels, and fmet values of glucuronides were observed after short hairpin RNA (shRNA)-mediated silencing of transporters BCRP and MRP1. Taken together, our results indicate that MRP3 and MRP4 contribute more to the excretion of fraxetin-O-glucuronides than the other transporters do.

Ulcerative colitis (UC) is one of the primary inflammatory bowel diseases (IBDs) and causes a serious threat to human public health around the world. Currently, there are no proven safe and effective treatment options to treat UC. Fraxetin (Fxt) is a widely recognized antioxidant and anti-inflammatory legume derived from ash bark. In the present study, we investigated the protective effect and mechanism of Fxt on UC. Our results showed that Fxt significantly attenuated the body weight, colon length reduction, tissue damage, and disease activity index induced by dextran sodium sulphate (DSS). Moreover, the DSS-induced activation of the NF-κB pathway and NLRP3 inflammasomes was inhibited, and the inflammatory response was reduced. Fxt restored gut barrier function by increasing the number of goblet cells and the levels of tight junction proteins (ZO-1 and occludin). In addition, Fxt can alter the intestinal microbiota by enhancing the diversity of the microbiota, increasing the relative abundance of beneficial bacteria and inhibiting the growth of harmful bacteria. These results revealed that Fxt alleviates DSS-induced colitis by modulating the inflammatory response, enhancing epithelial barrier integrity and regulating the gut microbiota. This study may provide a scientific basis for the potential therapeutic effect of Fxt in the prevention of colitis and other related diseases., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors. Published by Elsevier Ltd.)

Fraxetin, a natural compound present in many dietary supplements and herbs, is useful in the treatment of acute bacillary dysentery and type 2 diabetes. Previously, several metabolic studies have revealed extensive first-pass metabolism causing formation of fraxetin- O -glucuronides (G1 and G2), resulting in poor bioavailability of fraxetin. Active transport processes play an important role in the excretion of fraxetin- O -glucuronides. Nevertheless, the transporters involved are yet to be elucidated. In this study, we aimed to determine the active efflux transporters, including breast cancer resistance protein (BCRP) and multidrug resistance-associated proteins (MRPs), involved in the excretion of fraxetin- O -glucuronides. A chemical inhibitor, MK571 (5 and 20 μM), a pan-MRP inhibitor, led to a significant decrease in excreted G1 (maximal 59.1%) and G2 levels (maximal 42.4%), whereas Ko143 (5 and 20 μM), a selective BCRP inhibitor, caused moderate downregulation of excreted G1 (maximal 29.4%) and G2 (maximal 28.5%). Furthermore, MRP3 silencing resulted in a marked decrease of excretion rates (by 29.1% for G1 and by 21.1% for G2) and of fraction metabolized (f met; by 24.1% for G1 and by 18.6% for G2). Similar results, i.e., a significant reduction in excretion rates (by 34.8% for G1 and by 32.3% for G2) and in f met (by 22.7% for G1 and by 23.1% for G2) were obtained when MRP4 was partially silenced. No obvious modifications in the excretion rates, intracellular levels, and f met values of glucuronides were observed after short hairpin RNA (shRNA)-mediated silencing of transporters BCRP and MRP1. Taken together, our results indicate that MRP3 and MRP4 contribute more to the excretion of fraxetin- O -glucuronides than the other transporters do. [ABSTRACT FROM AUTHOR]

Lung cancer represents the leading cause of cancer-associated mortality, and non-small-cell lung cancer (NSCLC) is the most frequent histologic sub-type. It is therefore urgent to develop novel agents for the treatment of NSCLC. Fraxetin (FXT) is a potent plant-derived product and has been recognized as a promising anticancer agent for breast cancer and osteosarcoma. However, the anti-cancer potential of FXT for NSCLC remains to be elucidated. Accordingly, in the present study, we evaluated the inhibitory effect of FXT on the proliferation and growth of NSCLC cells using six human NSCLC cell lines: A549, H460, HCC827, H1650, PC-9 and H1975. FXT exhibited significant inhibitory effects on the proliferation of these cancer cell lines. By contrast, no inhibitory effect was observed on the viability of non-cancer lung cell lines even at the highest concentration of FXT (100 µM). Among the NSCLC cell lines, HCC827 and H1650 cells showed the most sensitive to FXT. Accordingly, HCC827 and H1650 cells were used for the subsequent experiments. Flow cytometric analysis revealed that FXT caused a significant cell cycle arrest and pro-apoptotic effects. Mechanistically, FXT suppressed the IL-6-induced phosphorylation of tyrosine residue (Tyr705) of signal transducer and activator of transcription 3 (STAT3) probably by binding to STAT3. Molecular docking and molecular dynamic simulations studies indicated that FXT interacts with STAT3 through hydrogen bond and hydrophobic interaction. In conclusion, these findings suggest that FXT could be a promising lead compound to be used as a novel STAT3 inhibitor and potential antitumor agent for the treatment of NSCLC. [ABSTRACT FROM AUTHOR]

Fraxetin is a coumarin scaffold compound extracted from Fraxinus rhynchophylla. It has antioxidant, anti-inflammatory, hepatoprotective, and antifibrotic effects. Furthermore, fraxetin has anticancer effects in breast and lung cancer. We aimed to evaluate whether fraxetin has anticancer activity in hepatocellular carcinoma (HCC) cells and its underlying mechanism. We demonstrated the anticancer effects of fraxetin in the HCC cell lines Huh7 and Hep3B. We confirmed that fraxetin inhibited cell proliferation (42% ± 10% Huh7; 52% ± 7% Hep3B) by arresting the cell cycle and inducing apoptosis in both cell lines. Moreover, fraxetin increased reactive oxygen species production (221% ± 55% Huh7; 460% ± 73% Hep3B), depolarized the mitochondrial membranes (ΔΨm) (345% ± 160% Huh7; 462% ± 140% Hep3B), and disrupted calcium homeostasis in both HCC cell lines. Chelating calcium ions with BAPTA-AM restored proliferation in fraxetin-treated Huh7 cells but not in Hep3B cells. Fraxetin did not affect the phosphorylation of extracellular-signal-regulated kinase 1/2, whereas it decreased JNK and phosphoinositide 3-kinase signaling. Furthermore, fraxetin and mitogen-activated protein kinase pharmacological inhibitors had synergistic antiproliferative effects on HCC cells. Although our study was limited to in vitro data that require validation, we suggest that fraxetin is a potential therapeutic agent against HCC progression.

Iron deficiency is a serious agricultural problem, particularly in alkaline soils. Secretion of coumarins by Arabidopsis thaliana roots is induced under iron deficiency. An essential enzyme for the biosynthesis of the major Arabidopsis coumarins, scopoletin and its derivatives, is Feruloyl-CoA 6'-Hydroxylase1 (F6'H1), which belongs to a large enzyme family of the 2-oxoglutarate and Fe2+-dependent dioxygenases. We have functionally characterized another enzyme of this family, which is a close homologue of F6'H1 and is encoded by a strongly iron-responsive gene, At3g12900. We purified At3g12900 protein heterologously expressed in Escherichia coli and demonstrated that it is involved in the conversion of scopoletin into fraxetin, via hydroxylation at the C8 position, and that it thus functions as a scopoletin 8-hydroxylase (S8H). Its function in plant cells was confirmed by the transient expression of S8H protein in Nicotiana benthamiana leaves, followed by metabolite profiling and biochemical and ionomic characterization of Arabidopsis s8h knockout lines grown under various iron regimes. Our results indicate that S8H is involved in coumarin biosynthesis, as part of mechanisms used by plants to assimilate iron. [ABSTRACT FROM AUTHOR]

The present study was designed to investigate the possible protective effects of fraxetin against ethanol induced liver fibrosis in rats. Rats were underwent intragastric administration of ethanol (5.0–9.5 g/kg) once a day for 24 weeks. Effect of fraxetin against ethanol induced liver fibrosis was investigated by giving 20 or 50 mg/kg fraxetin. At the end of experiment, the livers were collected for histopathological analyses, protein extraction, and enzymatic activities. Our results indicated that fraxetin significantly corrected ethanol-induced hepatic fibrosis, as evidenced by the decrease in serum ALT and AST, the attenuation of histopathological changes. Fraxetin also expedited ethanol metabolism by enhancing the alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) activities. Besides, fraxetin alleviated lipid peroxidation, enhanced hepatic antioxidant capabilities, inhibited CYP2E1 activity, and reduced the inflammatory mediators, including TNF-α and IL-1β via up-regulation of hemeoxygenase-1 (HO-1) protein. In summary, the hepatoprotection of fraxetin is mostly attributed to its antioxidant capability, alcohol metabolism, and anti-inflammation effect. [ABSTRACT FROM AUTHOR]

The aim of the present study was to examine the effect of fraxetin on proliferation and apoptosis in the MCF-7 breast cancer cell line. Cell proliferation was measused using an MTT assay and 4’,6-diamidino-2-phenylindole (DAPI) staining was used to determine shrinkage and condensation. RT-PCR was used to examine the expression of factor‑associated suicide (Fas) and Fas ligand (FasL) mRNA, and western blot analysis was used to examine Bax and Bcl-2 protein. MTT showed that the proliferation of MCF-7 cells was significantly inhibited by fraxetin in a dose-dependent manner. Fraxetin also induced significant morphological changes of MCF-7 cells, suggestive of apoptosis, whereas DAPI staining showed that fraxetin caused cell shrinkage and chromatin condensation. RT-PCR showed that the expression of Fas and FasL mRNA was upregulated by fraxetin and the western blot analysis revealed that Bax was upregulated and Bcl-2 was downregulated. In conclusion, fraxetin can inhibit the proliferation of MCF-7 cells, induce apoptosis, upregulate Fas, FasL and Bax, and downregulate Bcl-2 to induce apoptosis. These results support the potential therapeutic role for fraxetin in breast cancer. [ABSTRACT FROM AUTHOR]

Background: Lawsonia inermis L. is a well-documented plant for cosmetic as well as medicinal properties. It is used by local communities in India and Nigeria for the treatment of many parasitic diseases, including malaria.Hypothesis/purpose: Earlier studies on the plant's antiplasmodial activity were not assigned to any phytochemical with no quality assurance data. In this report, a recent chemically characterized extract and it's major constituent were investigated for in vitro antiplasmodial activity on chloroquine sensitive NF-54 strain. Furtherly, the potent extract and this constituent were assessed in vivo in Plasmodium berghei infected mice. The bioactive phytochemical and enriched extract were also monitored against various oxidative stress parameters.Study Design/method: The extract characterization was done by the quantitative analysis of eight phytochemicals using gradient reverse phase HPLC method. In vitro antiplasmodial activity was evaluated on chloroquine sensitive NF-54 strain by the determination of pfLDH activity. In vivo activity of the most potent extract and constituent were evaluated in P. berghei infected mice upon oral administration. The estimation of oxidative stress was done by monitoring various enzymatic and non-enzymatic parameters.Results: The ethyl acetate extract of leaves (IC50 9.00 ± 0.68 µg/ml) and fraxetin (IC50 19.21 ± 1.04 µM) were the most effective in in vitro assays therefore selected for in vivo tests. The administration of the ethyl acetate extract of leaves and fraxetin to the infected mice resulted in significant (p < .05) suppression of parasitaemia as evidenced by a 70.44 ± 2.58% to 78.77 ± 3.43% reduction compared to non-infected group. In addition, a two-fold increase in mean survival time, a significant (p < .05) reduction in lipid peroxidation and an elevation in glutathione, catalase and superoxide dismutase were also observed in treated mice. The post-infection treatment also led to an augmentation of endogenous antioxidant enzymes (GST, GR, GPx) with respect to the infected control. A significant (p < .05) elevation in serum Nrf2-antioxidant response element level responsible for the activation of endogenous enzymes was also observed.Conclusion: It was evident from the experiments that ethyl acetate extract of L. inermis and fraxetin were able to suppress the oxidative damage by augmenting endogenous antioxidant system and thus ameliorated the plasmodium infection in mice. [ABSTRACT FROM AUTHOR]

Root secretion of coumarin-phenolic type compounds has been recently shown to be related to Arabidopsis thaliana tolerance to Fe deficiency at high pH. These studies revealed the identity of a few simple coumarins occurring in roots and exudates of Fe-deficient A. thaliana plants, and left open the possible existence of other unknown phenolics. We used HPLC-UV-VIS-ESI-MS(TOF), HPLC/ESI-MSn(ion trap) and HPLC-ESI-MS-MS(Q-TOF) to characterize (identify and quantify) phenolic-type compounds accumulated in roots or secreted into the nutrient solution of A. thaliana plants in response to Fe deficiency. Plants grown with or without Fe and using nutrient solutions buffered at pH 5.5 or 7.5 enabled to identify an array of phenolics. These include several coumarinolignans not previously reported in A. thaliana (cleomiscosins A, B, C and D and the 5’-hydroxycleomiscosins A and/or B), as well as some coumarin precursors (ferulic acid and coniferyl and sinapyl aldehydes), and previously reported cathecol (fraxetin) and non-cathecol coumarins (scopoletin, isofraxidin and fraxinol), some of them in hexoside forms not previously characterized. The production and secretion of phenolics were more intense when the plant accessibility to Fe was diminished and the plant Fe status deteriorated, as it occurs when plants are grown in the absence of Fe at pH 7.5. Aglycones and hexosides of the four coumarins were abundant in roots, whereas only the aglycone forms could be quantified in the nutrient solution. A comprehensive quantification of coumarins, first carried out in this study, revealed that the catechol coumarin fraxetin was predominant in exudates (but not in roots) of Fe-deficient A. thaliana plants grown at pH 7.5. Also, fraxetin was able to mobilize efficiently Fe from a Fe(III)-oxide at pH 5.5 and pH 7.5. On the other hand, non-catechol coumarins were much less efficient in mobilizing Fe and were present in much lower concentrations, making unlikely that they could play a role in Fe mobilization. The structural features of the array of coumarin type-compounds produced suggest some can mobilize Fe from the soil and others can be more efficient as allelochemicals.

This paper reports the successive isolation and purification of bioactive compounds from the stem bark of Jatropha podagrica, a widely known medicinal plant. The ethyl acetate extract of the stem bark exhibited the strongest antioxidant activity assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging, and ferric reducing antioxidant power (FRAP) assays (IC50 = 46.7, 66.0, and 492.6, respectively). By column chromatography (CC) with elution of hexane and ethyl acetate at 8:2, 7:3, and 6:4 ratios, the isolation of this active extract yielded five fractions (C1–C5). Chemical structures of the constituents included in C1–C5 were elucidated by gas chromatography-mass spectrometry (GC-MS), electrospray ionization-mass spectrometry (ESI-MS), and nuclear magnetic resonance (NMR) and resolved as methyl gallate (C1, C2, C3, C4), gallic acid (C1, C2), fraxetin (C2, C3, C4, C5), and tomentin (C3). Mixture C2 (IC50 DPPH and ABTS = 2.5 µg/mL) and C3 (IC50 FRAP = 381 µg/mL) showed the highest antioxidant properties. Among the isolated fractions, C4 was the most potential agent in growth inhibition of six bacterial strains including Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Listeria monocytogenes, Bacillus subtilis, and Proteus mirabilis (MIC = 5, 20, 30, 20, 25, and 20 mg/mL, respectively). All identified constituents exerted an inhibitory activity on the growth of Lactuca sativa, of which the mixture C3 performed the maximal inhibition on shoot (IC50 = 49.4 µg/mL) and root (IC50 = 47.1 µg/mL) growth. Findings of this study suggest that gallic acid, methyl gallate, fraxetin, and tomentin isolated from J. podagrica possessed antioxidant, antibacterial, and growth inhibitory potentials.