Search Results (70)

Background: Chronic kidney disease (CKD) is characterized by irreversible structural damage and functional deterioration of the kidneys. Esculetin (ES), with its anti-inflammatory, antioxidant, and immunomodulatory activities, shows potential in delaying renal function decline. This study aimed to investigate the protective effect of ES on adenine-induced CKD in mice and its underlying molecular mechanism, with a focus on its role in preventing the transition from acute kidney injury (AKI) to CKD. Methods: A AKI-to-CKD transition mice model was established by feeding mice a 0.2% adenine diet, and ES (30, 60 mg/kg) was co-administered for 4 weeks as a prophylactic intervention. Serum creatinine (SCr), blood urea nitrogen (BUN), and renal histopathology (HE, Masson, IHC) were evaluated to assess renal injury. Network pharmacology and transcriptomics were combined to screen the targets, and Western blot was used to verify the signaling pathways. Results: ES significantly reduced SCr and BUN levels in CKD mice and alleviated renal tubular dilation and inflammatory infiltration. ES decreased pro-inflammatory factors (IL-1β, IL-6, TNF-α) and MDA levels and enhanced SOD activity. Additionally, ES inhibited renal interstitial collagen deposition and reversed epithelial–mesenchymal transition (EMT) by upregulating E-cadherin and downregulating α-SMA levels. Mechanism studies confirmed that ES significantly inhibited the phosphorylation levels of p-EGFR, p-SRC, p-PI3K, p-AKT, and p-p65 in renal tissues. Conclusions: ES effectively inhibits inflammation, oxidative stress, and fibrosis by modulating the EGFR/SRC/PI3K/AKT/NF-κB signaling axis, thereby preventing the AKI-to-CKD transition in the adenine-induced renal injury model and alleviating the progression of chronic renal damage. Full article

Background: Crop plants have to deal with long-term cadmium exposure to farmlands contaminated by intensive use of fertilizers and pesticides. For uptake and sequestration, Cd²⁺ has to pass the plasma membrane and tonoplast. Class III peroxidases, plasma membrane, and tonoplast sub-proteomes were studied. Methods: Control and Cd²⁺-treated maize (Zea mays L.) were grown in hydroponics for 18 days. Soluble peroxidases were partially purified by chromatofocusing and characterized by substrate specificity. Membrane-bound peroxidases were analyzed spectrophotometrically and by non-reducing SDS-PAGE. Soluble and plasma membrane-bound peroxidases were identified by mass spectrometry. Shotgun proteomics was used to identify membrane proteins of differential abundance. Results: Guaiacol peroxidase activities increased in soluble fractions of Cd²⁺ samples. A Cd²⁺-specific soluble peroxidase (ZmPrx101) was identified, and ZmPrx85 abundance increased significantly in the plasma membrane. Substrate specificity of peroxidases revealed a preference for ferulic acid and esculetin, which was confirmed by docking analyses. Primary active transporters increased auxin efflux (brachytic2, ABCB9, and ABCB21), Cd²⁺ exclusion (ABCG34), and sequestration into the vacuole (HMA2, ABCB27). Evaluation of sub-proteome fractions demonstrated significant changes for proteins involved in disease resistance responses and cell wall modification. Conclusions: Molecular adjustments of maize root proteome to long-term Cd²⁺ exposure revealed relevance of low-abundant proteins for Cd²⁺ tolerance and putative stress markers. Full article

Coleus strobilifer, the dried rhizome and root of Coleus strobilifer (Roxb.) A.J. Paton, is widely used for dampness-detoxification and detumescence in Chinese folklore. This study marks the first comprehensive investigation into the chemical composition of the whole herb of C. strobilifer, leading to the isolation and identification of two new abietane diterpenes, 10R-carnosuain (1) and 10R-coleon U-3-one (2), along with 34 known compounds (3–36) isolated from C. strobilifer for the first time. Their structures were unambiguously elucidated by analyses of NMR, HRESIMS, IR, CD, and single-crystal X-ray diffraction data, and comparison with the literature. All the isolated compounds were screened for their xanthine oxidase (XO) inhibitory activity. Among them, apigenin (8), luteolin (9), and esculetin (29) showed moderate XO inhibitory activity with IC₅₀ values of 0.034 ± 0.004, 0.067 ± 0.005, and 0.284 ± 0.01 mM, respectively. Full article

Background/Objectives: Metastatic prostate cancer is among the therapy-resistant human neoplasms. PC-3 is a commonly used experimental cell line that does not express androgen receptors. We compared the cytotoxicity of esculetin with that of vinblastine and paclitaxel on prostatic tumour PC-3 cells. Methods: Cells were treated with either esculetin (100 or 250 μM), vinblastine (50 μM) or paclitaxel (100 or 200 μM) for 19 to 72 h. Cells were assessed for metabolic viability, membrane integrity, DNA fragmentation and cell cycle analysis. Apoptosis was checked with annexin and propidium iodide. Results: Esculetin decreased the metabolic activity of PC-3 cells in a time- and concentration-dependent way. The metabolic activity of vinblastine- and paclitaxel-treated cells did not show time-dependence. Cells treated with 250 µM esculetin for 48 or 72 h showed apoptosis levels similar to those produced by 50 µM vinblastine at these incubation times or by 200 µM paclitaxel at 19 h. Vinblastine and paclitaxel produced cell cycle arrest in the G2/M phase after incubation for 19 h. In contrast, esculetin did not significantly affect the cell cycle. Conclusions: A differential action of esculetin on PC-3 prostate cells may be inferred. This may be relevant for novel therapies against resistant prostate cancer. Full article

In this study, we evaluated the antioxidant activities of esculetin and four synthesized derivatives (E1, 2-oxo-2H-1-benzopyran-6,7-diyl diacetate; E2, 7-hydroxy-2-oxo-2H-1-benzopyran-6-yl acetate; E3, 7-(methoxymethoxy)-2-oxo-2H-1-benzopyran-6-yl acetate; E4, 7-hydroxy-2-oxo-2H-1-benzopyran-6-yl 2,4-dinitrobenzene-1-sulfonate) against oxidative stress in hepatocytes. In HepG2 cells, treatment with 1 mM tert-butyl hydroperoxide (TBHP) reduced cell viability to 40%, while co-treatment with esculetin restored cell viability. Among the esculetin derivatives, E2 exhibited the most significant cytoprotective effect, while E4 showed the lowest. Furthermore, E2 at 25 µM concentration showed the similar effects to esculetin in reducing ROS generation and preventing glutathione depletion. The treatment of E2 also enhanced the expression of HO-1 and GCLC proteins against oxidative stress. On the other hand, TBHP-induced oxidative stress decreased antioxidant activities including glutathione reductase, glutathione peroxidase, and catalase; however, E2 significantly increased these antioxidant activities. These findings suggest that the esculetin derivative, particularly E2, possesses potential as an antioxidant aimed at enhancing physiological functions. Full article

Fomes fomentarius (L.) Fr. has been valued since the 15th century across Europe, including the Balkan region, for its medicinal and traditional uses such as tinder production, spiritual practices, wound healing, and hemostasis. This study analyzes three Balkan strains, focusing on micro- and macroelements, polyamines (PAs), and phenolic compounds in hot water (H₂O), chloroform (CHCl₃), hydroethanolic (EtOH), and hydromethanolic (MeOH) extracts. Micro- and macroelements were determined using atomic absorption spectrophotometry (AAS), while PAs were quantified using high-performance liquid chromatography with fluorescence detection (HPLC-FD). Phenolic profiles were determined using liquid chromatography–mass spectrometry (LC-MS/MS), with total phenolic content (TPC) assessed using the Folin–Ciocalteu method. Antioxidant activity was evaluated via DPPH, ABTS, NO scavenging, lipid peroxidation inhibition, and FRAP assays, alongside anti-acetylcholinesterase and antiproliferative activity assessments. This study represents the first investigation of PA profiles in F. fomentarius, with total PA levels ranging from 32.67 to 2910.09 nmol/g dry weight (d.w.). The Bosnian strain exhibited the highest PA levels, with spermidine (SPD) concentrations ranging from 899.96 to 2910.09 nmol/g d.w. LC-MS/MS analysis identified several bioactive phenolics, including amentoflavone, baicalein, chrysoeriol, esculetin, and scopoletin—reported here for the first time in this fungus. The H₂O and EtOH extracts from the Croatian and Serbian strains showed higher TPC levels, correlating with notable antioxidant activity. The EtOH and MeOH extracts demonstrated significant anti-acetylcholinesterase and antiproliferative activities, emphasizing their medicinal potential. These findings highlight the therapeutic potential of polar extracts from Balkan F. fomentarius. Full article

Coumarins are natural organic compounds widely found in plants that show promising anticancer properties. This article reviews the current research on the mechanisms of action of coumarins in cancer therapy, including the induction of apoptosis, inhibition of tumor cell proliferation, modulation of oxidative stress, and inhibition of angiogenesis and metastasis. Examples of coumarins with demonstrated anticancer activity, such as scopoletin, umbeliferon, esculetin and their synthetic derivatives, are also presented. The results of preclinical studies, the potential use of coumarins as stand-alone drugs and their role in combination therapy with chemotherapy are discussed. In addition, challenges related to bioavailability, safety and potential interactions with other drugs are highlighted. This review concludes by pointing out future research directions, such as the design of new coumarin analogs and the use of nanotechnology to enhance their efficacy in cancer treatment. Full article

Background: Esculetin, 6,7-dihydroxycoumarin, is a bioactive compound found in various herbal plants, and is known to have health-beneficial properties including anti-obesity effects. However, there is a lack of in vivo studies to clearly determine esculetin’s role in lipid metabolism. Objectives: In this study, we studied esculetin’s effect on lipid accumulation using Caenorhabditis elegans and its underlying mechanisms. Methods: C. elegans were treated with esculetin (100 or 200 μM) for 48 h, and their triglyceride and protein levels were measured. Additionally, behavioral patterns such as pharyngeal pumping rate, body bending rate, body sizes, and locomotive activity were analyzed. Genetic dependencies were examined by utilizing mutant worms and testing relative gene expressions. Results: C. elegans treated with esculetin displayed significantly reduced fat accumulation compared to the controls without effects on the pharyngeal pumping rate, body bending rate, or locomotive activity. Esculetin’s fat-lowering effect was dependent on DAF-2 (insulin/insulin-like growth factor-1 [IGF-1] receptor homolog), DAF-16 (Forkhead box protein O homolog), and AAK-2 (5′-adenosine monophosphate-activated protein kinase [AMPK] catalytic subunit α2) in the mutant experiments. Esculetin also significantly increased the relative expression of downstream targets of DAF-16 (hsp-16.2 and sod-3), AMPK-related genes (aak-1 and aak-2), a sirtuin gene, sir-2.1, and a lipolysis-related gene, atgl-1. Conclusions: These findings suggest that esculetin inhibited fat accumulation in C. elegans and this effect was dependent on the insulin/IGF-1 and 5′-adenosine monophosphate-activated protein kinase signaling pathways. Full article

This study investigates the chemical profiling of Croatian whisky using advanced analytical techniques: Solid-phase microextraction followed by gas chromatography coupled to mass spectrometry (SPME-GC-MS) and ultra-high-performance liquid chromatography quadrupole time-of-flight (UHPLC-QTOF). To our knowledge, there are no studies on profiling Croatian whiskies to date. Therefore, the primary objective is to identify and quantify the volatile and non-volatile compounds contributing to the flavor and aroma profile of Croatian whisky. The methods applied included sample preparation, extraction, and subsequent analysis using these advanced analytical techniques. The results revealed a diverse range of compounds, including esters, alcohols, phenols, and acids, which are integral to the whisky’s sensory characteristics. Furthermore, key volatile and non-volatile compounds were identified in Croatian whiskies, revealing a complex aromatic profile influenced by compounds like D-limonene, linalool, and β-damascenone, which contribute citrus, floral, and fruity notes. The findings also highlighted compounds associated with aging, such as esculetin and ellagic acid, which enhance flavor complexity and emphasized the role of maturation, grain type, and production methods in shaping the unique sensory characteristics of Croatian whiskies. This study concludes that SPME-GC-MS and UHPLC-QTOF are effective tools for the detailed chemical profiling of whisky, providing valuable insights for quality control and product differentiation in the whisky industry. Full article

Cocoa and coffee are two of the world’s most important crops. Therefore, their by-products are generated in large quantities. This work proposes a simple method for the valorization of these residues by obtaining phenolic compounds and melanoidins by solid–liquid extraction using different hydroalcoholic solutions as extracting solvents (0, 25, 50, 75, 100% ethanol). Extracts of both by-products presented the highest antioxidant capacity and total phenolic and melanoidin content when using 50–75% ethanol in the solvent. Among all the extracts, those obtained from spent coffee grounds at 75% ethanol showed the highest concentrations of total phenolic compounds (13.5 ± 1.3 mmol gallic acid equivalents/g dry matter) and melanoidins (244.4 ± 20.1 mg/g dry matter). Moreover, the sun protection factor values of the coffee extracts obtained with 50 and 75% of ethanol as extraction solvent (7.8 ± 0.9 and 8.5 ± 0.7, respectively) showed their potential for use in the cosmetic sector. The most important phenolic compounds identified in the coffee by-products extracts were phenolic acids, and most of them were found in higher concentration in extracts obtained with lower percentages of ethanol (0–25%). Protocatechuic acid was the most abundant phenolic in cocoa extracts, with concentrations ranging from 18.49 ± 2.29 to 235.35 ± 5.55 µg/g dry matter, followed by 4-hydroxybenzoic acid, (-)-epicatechin and (+)-catechin. Esculetin was found in both coffee and cocoa extracts, which had not been reported to date in these residues. In summary, the use of 75% ethanol as an extraction solvent seems a good strategy to obtain extracts rich in phenolic compounds from food by-products rich in melanoidins, such as coffee and cocoa by-products. The high antioxidant potential of these extracts makes them of great interest for the cosmetic and nutraceutical industries. Full article

Respiratory syncytial virus (RSV) is one of the most prevalent viruses that causes severe acute lower respiratory tract infections (ALRTIs) in the elderly and young children. There is no specific drug to treat RSV, only a broad-spectrum antiviral, ribavirin, which is only used in critical cases. Our research group is investigating antiviral agents of natural origin, such as coumarins and flavonoids, that may help reduce or prevent RSV infection. The cytotoxic concentrations of coumarins and hesperetin were tested on A549 and HEp-2 cells and used in inhibition tests in which 80% of the cells were viable. The anti-RSV action of the molecules was analyzed in A549 and HEp-2 cells and in HBE cell cultures infected with RSV-luc or rgRSV. We also encapsulated the compounds using β-cyclodextrin to improve the permeability and solubility of the molecules. Esculetin and 4-methyl inhibited rgRSV effectively on A549 and HEp-2 cells after 24 hpi, and when they were encapsulated, coumarin, esculetin, and hesperetin presented inhibition against rgRSV in HBE culture. The coumarins inhibit RSV replication in cell culture and even manage to overcome the mucus barriers of the HBE cultures, and β-cyclodextrin was essential for some of the coumarins to enter the cell and therefore to reach their targets. Full article

The skin hydration level is a key factor that influences the physical and mechanical properties of the skin. The stratum corneum (SC), the outermost layer of the epidermis, is responsible for the skin’s barrier function. In this study, we investigated the role of a unique composition of Viola yedoensis extract for its ability to activate CD44, a cell-surface receptor of hyaluronic acid, and aquaporin-3, a water-transporting protein, in human keratinocytes (HaCaT). An ELISA assay evaluating the protein expression levels of CD44, aquaporin-3 (AQP3), filaggrin, and keratin-10 revealed that V. yedoensis extract upregulated the levels of CD44 and AQP3 by 15% and 78%, respectively. Additionally, V. yedoensis extract demonstrated a comparative effect on water vapor flux in TEWL and lipid perturbation in DSC versus the reference, glycerin. In light of this new biological efficacy, a detailed phytochemical characterization was undertaken using an integrated LC-HRMS/MS-based metabolomics approach, which provided further insights on the chemistry of V. yedoensis. This led to the identification of 29 secondary metabolites, 14 of which are reported here for the first time, including esculetin, aesculin, apigenin and kaempferol C-glycosides, megastigmane glycosides, roseoside, platanionoside B, and an eriojaposide B isomer, along with the rare, calenduloside F and esculetin diglucoside, which are reported for the first time from the genus, Viola. Notably, two active components identified in the V. yedoensis extract, namely, aesculin and schaftoside, showed an upregulation of the protein expression of CD44 in HaCaT cells by 123% and 193% within 24 h of treatment, respectively, while aesculin increased AQP3 levels by 46%. Aesculin and schaftoside also significantly upregulated the expression of K-10 levels by 299% and 116%, which was considerably higher than sodium hyaluronate, the positive control. The rationale used to characterize the new structures is outlined along with the related biosynthetic pathways envisioned to generate roseoside and Eriojaposide B. These findings provide new molecular insights to deepen the understanding of how V. yedoensis extract, along with the biomarkers aesculin and schaftoside, restores the skin barrier and skin hydration benefits. Full article

The increasing incidence of multidrug-resistant (MDR) Salmonella enterica serovar Typhimurium (S. Tm), known for causing invasive enteric infections, presents a significant public health challenge. Given the diminishing efficacy of existing antibiotics, it is imperative to explore novel alternatives for the treatment of MDR S. Tm infections. Here, we identified esculetin (EST), a natural coumarin abundant in dietary foods and herbs, as a compound exhibiting broad-spectrum antibacterial properties against a range of MDR bacteria. Our findings demonstrate that EST effectively inhibited the proliferation and expansion of MDR S. Tm in both in vitro experiments and animal models. Specifically, EST significantly downregulated the type 3 secretion system-1 (T3SS-1) virulence expression of MDR S. Tm, thereby preventing its invasion into intestinal epithelial cells. In S. Tm-infected mice, we observed cecal injury characterized by the upregulation of inflammatory cytokines, a reduction in goblet cell numbers, a decreased expression of tight junction proteins, and microbial dysbiosis. Conversely, EST treatment ameliorated these pathological changes induced by S. Tm infection and reduced oxidative stress by activating the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway, thereby improving intestinal barrier function. These results suggest that dietary coumarins or a targeted plant-based diet may offer a promising strategy to counteract MDR bacteria-induced enteric diseases. Full article

Oxidative stress plays a crucial role in the pathogenesis of many diseases. Esculetin is a natural coumarin compound with good antioxidant and anti-inflammatory properties. However, whether esculetin can protect HepG2 cells through inhibiting H₂O₂-induced apoptosis and pyroptosis is still ambiguous. Therefore, this study aimed to investigate the protective effects and mechanisms of esculetin against oxidative stress-induced cell damage in HepG2 cells. The results of this study demonstrate that pretreatment with esculetin could significantly improve the decrease in cell viability induced by H₂O₂ and reduce intracellular ROS levels. Esculetin not only apparently reduced the apoptotic rates and prevented MMP loss, but also markedly decreased cleaved-Caspase-3, cleaved-PARP, pro-apoptotic protein (Bax), and MMP-related protein (Cyt-c) expression, and increased anti-apoptotic protein (Bcl-2) expression in H₂O₂-induced HepG2 cells. Meanwhile, esculetin also remarkably reduced the level of LDH and decreased the expression of the pyroptosis-related proteins NLRP3, cleaved-Caspase-1, Il-1β, and GSDMD-N. Furthermore, esculetin pretreatment evidently downregulated the protein expression of p-JNK, p-c-Fos, and p-c-Jun. Additionally, anisomycin, a specific activator of JNK, blocked the protection of esculetin against H₂O₂-induced HepG2 cells apoptosis and pyroptosis. In conclusion, esculetin can protect HepG2 cells against H₂O₂-induced oxidative stress, apoptosis, and pyroptosis via inhibiting the JNK signaling pathway. These findings indicate that esculetin has the potential to be used as an antioxidant that improves oxidative stress-related diseases. Full article

Pimpinella anisum L., or anise, is a plant that, besides its nutritional value, has been used in traditional medical practices and described in many cultures in the Mediterranean region. A possible reason for anise’s therapeutic value is that it contains coumarins, which are known to have many biomedical and antioxidant properties. HPLC analysis in our laboratory of the anise extract shows the presence of the coumarin esculetin. We used a hydrodynamic voltammetry rotating ring–disk electrode (RRDE) method to measure the superoxide scavenging abilities of anise seeds and esculetin, which has marked scavenging activity. A related coumarin, 4-methyl-esculetin, also showed strong antioxidant activity as measured by RRDE. Moreover, this study includes the X-ray crystal structure of esculetin and 4-methyl-esculetin, which reveal the H-bond and the stacking intermolecular interactions of the two coumarins. Coordinates of esculetin crystal structure were used to perform a DFT study to arrive at the mechanism of superoxide scavenging. Besides performing a H(hydroxyl) abstraction in esculetin position 6 by superoxide, the scavenging also includes the presence of a second superoxide radical in a π–π approach. Both rings of esculetin were explored for this attack, but only the pyrone ring was effective. As a result, one product of esculetin scavenging is H₂O₂ formation, while the second superoxide remains π–π trapped within the pyrone ring to form an esculetin-η-O₂ complex. Comparison with other coumarins shows that subtle structural differences in the coumarin framework can imply marked differences in scavenging. For instance, when the catechol moiety of esculetin (position 6,7) is shifted to position 7,8 in 4-methyl-7,8-dihydroxy coumarin, that coumarin shows a superoxide dismutase action, which, beside H₂O₂ formation, includes the formation and elimination of a molecule of O₂. This is in contrast with the products formed through esculetin superoxide scavenging, where a second added superoxide remains trapped, and forms an esculetin-η-O₂ complex. Full article