Search Results (373)

Objectives: Pseudomonas aeruginosa is an opportunistic pathogen of high clinical relevance due to its ability to form biofilms, its inherent virulence regulated by quorum-sensing systems, and its multidrug resistance. In the present study, we evaluated the inhibitory potential of nine extracts from Inula species (chloroform and methanolic fractions, including a sesquiterpene lactone-enriched fraction) against biofilm formation and virulence-associated traits of P. aeruginosa PAO1 and three multidrug-resistant clinical isolates, as well as their cytotoxicity, biocompatibility, and ability to affect cytokine and nitric oxide production in infected skin explants. Methods: The following methods were applied: fractionation and extraction of plant extracts; cytotoxicity assessment on HFF cells; crystal violet assay for determining antibiofilm activity; fluorescence microscopy for evaluating biofilm viability; electron microscopy for assessing the 3D structure of biofilms and morphological alterations; inhibition assays of pyocyanin pigment, protease activity, bacterial motility, interleukin-17, and nitric oxide production; histological analysis of mouse skin explants. Results: Quantitative analyses of antibiofilm activity revealed that five of the tested extracts inhibited biofilm formation by more than 50%. Structural and functional analyses using confocal laser scanning microscopy and scanning electron microscopy demonstrated a substantial reduction in biofilm thickness, exfoliation of biofilm biomass, the presence of isolated bacterial clusters, metabolically inactive cell populations, and morphological abnormalities associated with cell elongation, invaginations, and polar deformations as a consequence of treatment. In addition, the plant extracts strongly affected virulence factors regulated by quorum sensing. The methanolic fractions from I. britannica and I. bifrons significantly suppressed pyocyanin synthesis. In contrast, the chloroform fractions from I. helenium and I. spiraeifolia produced the largest inhibition zones in assays for extracellular protease activity. Furthermore, all chloroform extracts suppressed bacterial motility, with the lowest swarming diameter observed for the chloroform and lactone-enriched fractions from I. britannica. The chloroform extracts of I. helenium and I. bifrons, methanolic extracts of I. britannica, and chloroform and methanolic extracts of I. spiraeifolia showed relatively low toxicity to normal diploid human fibroblasts. Methanolic and chloroform fractions from I. britannica disrupted biofilm integrity and reduced IL-17A and nitric oxide production in infected skin explants. Conclusions: All these findings indicate a possible synergistic action of the chemical constituents within the fractions on quorum-sensing regulation, biofilm formation, cellular viability, and modulation of host inflammatory responses. Full article

Background: Fusarium solani (Fs), a drug-resistant phytopathogenic fungus, is a major cause of severe infections in both plants and humans. Artemisia annua and its derivatives exhibit antimicrobial, antiviral and anticholesterolemic activities, yet their clinical use has been dominated by potent antimalarial and anticancer effects. Artemisinin (ART), a sesquiterpene lactone isolated from A. annua, is well recognized for its antimalarial efficacy but remains underexplored as an antifungal agent. Methods: Conidia of Fs were treated with increasing concentrations of ART (75–500 μM) for 0 and 24 h. Fungal viability was assessed using viability assays. Membrane permeability was examined using confocal laser scanning microscopy with propidium iodide (PI) staining. Protein carbonylation assays were performed to quantify oxidative damage induced by ART. Results: A 24 h, ART exposure reduced Fs viability in a dose-dependent manner, with an IC₅₀ of 147.5 μM. At 500 μM, ART achieved fungicidal activity with 99% growth inhibition. Confocal microscopy confirmed extensive membrane disruption in ART-treated conidia, while carbonylation assays demonstrated marked protein oxidation, supporting a mechanism involving free radical generation from the peroxide bridge of ART. ART exhibits potent antifungal activity against Fs, mediated by oxidative stress, membrane disruption and protein carbonylation. Conclusions: These findings highlight ART as a promising candidate for antifungal drug development against resistant Fusarium species. Full article

Sesquiterpenes are a diverse class of natural products that have garnered considerable interest for their potent bioactivity and structural variability. This review highlights advances in the derivatization of various sesquiterpene lactones, quinones, and alcohols, particularly in targeting cancer and neurodegenerative diseases. The structural modifications discussed include the incorporation of triazole, arylidene, or thiol moieties with eudesmane, guaiane, and germacranolide-type sesquiterpenes, among others. In addition, the conjugation with chemotherapeutics, as well as the development of nanoscale therapeutics, is also discussed. Such modifications have expanded the pharmacological potential, enabling improved specificity, cytotoxicity profiles, and sensitization toward tumor cells. Additionally, sesquiterpenes such as parthenolide (20), pterosinsade A (176), and cedrol (186) have demonstrated potential in mitigating neurodegeneration via anti-inflammatory and antioxidant signaling pathway-modulation mechanisms, with potential applications in Alzheimer’s, Parkinson’s, and ALS diseases. Mechanistic insights into redox signaling modulation, NF-κB inhibition, ROS regulation, and disruption of aggregation underscore their multifaceted modes of action. This review highlights the translational promise of sesquiterpene derivatives as dual-action agents for potential drug development in a plethora of diseases that are caused by inflammation and free-radical damage. It provides a framework for future rational design of multifunctional drug candidates and therapeutics. Full article

Laserpitium siler subsp. siculum (Apiaceae) is a Mediterranean plant with a long history of traditional medicinal use. In this study, the chemical composition and anticancer potential of three novel (and one new to the genus) sesquiterpene lactones (SLs) isolated from its roots were investigated. The structural characterization, carried out through NMR and HPLC-MS analyses, identified unique guaianolide-type lactones. The biological activity of these compounds was evaluated in vitro using MDA-MB-231 cells, a triple-negative breast cancer (TNBC) cell line. Cell viability assays demonstrated that all SLs tested reduced TNBC cell viability in a dose- and time-dependent manner, with SL-1 exhibiting the highest cytotoxicity. Light microscopy analyses and acridine orange/ethidium bromide staining confirmed the induction of apoptotic cell death, further supported by Western blot analyses showing caspase-3 activation and PARP-1 cleavage. Additional experiments indicated that SL-1 induced oxidative stress, as evidenced by increased ROS production and upregulation of the levels of the antioxidant enzymes MnSOD and HO-1. Moreover, JC-1 staining and Western blot analyses revealed mitochondrial membrane depolarization as well as a significant reduction in VDAC-1 expression, suggesting mitochondrial dysfunction as a key event in the cytotoxic mechanism. These findings highlight L. siler subsp. siculum as a promising source of bioactive compounds with anticancer potential. The ability of its sesquiterpene lactones to induce oxidative stress and mitochondrial impairment provides new insights into their mode of action, supporting further research into their therapeutic applications for TNBC treatment. Full article

The Jurubatiba Sandbank National Park (PARNA Jurubatiba) is an ecological reserve characterized by harsh environmental conditions, including low rainfall, high sun exposure, and sandy soil. Among its native vegetation, Eremanthus crotonoides stands out for its richness in flavonoids, phenolic compounds, and sesquiterpene lactones. The objective of this study was to isolate and quantify sesquiterpene lactones from this species using ¹H NMR and to investigate their anti-SARS-CoV-2 potential and cytotoxicity against cancer cells. UPLC-(ESI)-MS/MS analyses enabled metabolite annotation, and semi-preparative HPLC-DAD allowed the isolation of centratherin and goyazensolide, which were identified by 1D and 2D NMR. In vitro assays showed that centratherin at 10 µM concentration reduced the viability of PC-3 and HCT-116 cancer cells by 100%, while goyazensolide had no noteworthy effects. Furthermore, enzymatic inhibition assays on SARS-CoV2 targets revealed that centratherin exhibited a lower apparent IC₅₀ of 12 µM against PL^pro, while goyazensolide was more active against 3CL^pro, with an IC₅₀ of 71 µM. Notably, the dichloromethane fraction demonstrated promising activity against both enzymes, with IC₅₀ values of 30 µM for PL^pro and 11 µM for 3CL^pro. This study reports, for the first time, the isolation of goyazensolide from E. crotonoides and highlights the potential of both sesquiterpene lactones as SARS-CoV-2 enzyme inhibitors. In contrast to centratherin, goyazensolide fortunately had almost no cytotoxic effects at inhibition concentration on the cells tested. This shows that anticancer and anti-SARS effects can be separated and should have different SARs, an important prerequisite for further development. Full article

Artemisia frigida Willd. (A. frigida), a traditional medicinal herb widely distributed in northern China, Mongolia, and Siberia, has garnered increasing scientific interest due to its diverse phytochemical profile and extensive pharmacological potential. Modern studies have identified a wide range of bioactive compounds in A. frigida, including flavonoids, sesquiterpene lactones and phenolic acids. These compounds exhibit various biological activities, such as antioxidant, anti-inflammatory, anticancer, and antimicrobial effects. This review systematically summarizes the research progress on the chemical constituents of A. frigida and their extraction and separation methods, including solvent extraction, ultrasonic-assisted extraction, macroporous resin adsorption, and chromatography-based techniques. By integrating traditional knowledge with modern pharmacological evidence, this review provides a scientific foundation for the further development and utilization of A. frigida in functional food, pharmaceuticals, and ethnomedicine. Full article

Background: Acute lung injury (ALI) is a life-threatening respiratory condition and one of the leading causes of mortality worldwide, accounting for approximately 20% of global annual deaths. Despite its high prevalence and severity, effective therapeutic options remain limited. Eupatorium lindleyanum DC., a traditional medicinal herb, has demonstrated therapeutic potential against pulmonary diseases, particularly ALI, in both clinical and experimental settings. However, the protective effects and underlying mechanisms of its characteristic sesquiterpene lactone components against ALI remain unclear. Objective: This study aimed to evaluate the protective effects of sesquiterpene lactones from Eupatorium lindleyanum DC. (SLEL) against lipopolysaccharide (LPS)-induced ALI both in vivo and in vitro. Furthermore, it sought to elucidate the underlying mechanisms by integrating network pharmacology, multi-omics approaches (transcriptomics, metabolomics, and 16S rRNA sequencing), and various molecular biology techniques. Results: SLEL significantly attenuated inflammatory injury in alveolar epithelial cells and alleviated pulmonary edema, hemorrhage, and inflammatory infiltration in rats, accompanied by reduced TNF-α, IL-6, and IL-1β levels and improved lung injury indices. Mechanistically, SLEL exerted dual suppression of the PI3K-Akt and MAPK-NF-κB pathways. Network pharmacology, molecular docking, and UPLC-MS analyses identified Eupalinolide A and Eupalinolide K as potential bioactive constituents, which were further validated to inhibit phosphorylation of key signaling proteins, thereby partially accounting for SLEL’s pharmacological effects. Multi-omics integration further revealed that SLEL restored bile acid metabolism, reshaped gut microbial diversity, and reconstructed the microbiota–metabolite–inflammatory cytokine network, thereby maintaining gut–lung axis homeostasis and enhancing anti-inflammatory effects. Conclusions: SLEL alleviates ALI through multi-component synergistic actions that suppress pro-inflammatory signaling and modulate the gut–lung axis. These findings highlight the potential of SLEL as a promising therapeutic candidate for the treatment of ALI. Full article

Background: Prostate cancer (PC) progression is strongly driven by dysregulated signaling pathways, with NF-κB playing a central role. Sesquiterpene lactones have been reported to modulate this pathway. This study evaluated and compared the cytotoxic effects of two structurally distinct sesquiterpene lactones: Tatridin A, a germacranolide, and desacetyl-β-cyclopyrethrosin, a eudesmanolide derivative. Their mechanisms of action were also examined, focusing on oxidative stress induction and NF-κB modulation. Methods: Chemical structures were confirmed by NMR and X-ray crystallography. Cytotoxicity was assessed in DU-145 and 22Rv1 PC cells using real-time cell analysis. Reactive oxygen species (ROS) and mitochondrial membrane potential (ΔΨm) were measured with fluorometric assays. NF-κB activity was determined in THP-1 reporter cells and by Western blot of IκBα phosphorylation. Results: Tatridin A markedly reduced viability, showing lower IC₅₀ values (81.4 ± 2.7 µM in DU-145 and 50.7 ± 1.9 µM in 22Rv1 cells) than desacetyl-β-cyclopyrethrosin (166.9 ± 3.2 µM and 290.3 ± 8.3 µM, respectively). It also inhibited proliferation at markedly lower concentrations, with clonogenic IC₅₀ values of 7.7 µM in DU-145 and 5.24 µM in 22Rv1cells. Both compounds increased ROS, but tatridin A induced earlier and stronger responses and ΔΨm loss. Furthermore, tatridin A more effectively inhibited NF-κB signaling than classical inhibitors. Conclusions: Tatridin A exerts cytotoxic effects through oxidative stress, mitochondrial impairment, and NF-κB inhibition, supporting the therapeutic potential of germacranolides for the treatment of advanced PC. Full article

Colorectal cancer (CRC) remains a leading cause of cancer-related death worldwide, with resistance to targeted therapies presenting a significant clinical challenge. This study combines computational and experimental methods to identify and validate Antrocin, a natural sesquiterpene lactone, as a potential multi-target inhibitor of the BRAF/MEK/PI3K oncogenic pathway in CRC. Differential gene expression and mutational analyses were performed using public datasets (TCGA, TNMplot, GEPIA2, GSCA, PANDA, and cBioPortal) to assess the prevalence and clinical significance of BRAF, MEK, and PI3K alterations in CRC. In silico molecular docking, using AutoDock Vina, predicted strong binding affinities of Antrocin to BRAF (ΔG = −8.5 kcal/mol), MEK (ΔG = −7.3 kcal/mol), and PI3K (ΔG = −6.9 kcal/mol), comparable to those of FDA-approved inhibitors for BRAF (Dabrafenib), MEK (Trametinib), and PI3K (Alpelisib). Drug-likeness and ADME properties were evaluated via SwissADME and ADMETlab, supporting Antrocin’s potential as a drug candidate. In vitro assays using HCT116 and RKO CRC cell lines validated that Antrocin treatment suppressed cell viability, spheroid formation, and migration, accompanied by reduced expression levels of the oncogenic BRAF/MEK/PI3K signaling pathway. Antrocin-treated tumor-conditioned medium experiments demonstrated Antrocin’s ability to reduce the differentiation of cancer-associated fibroblasts and the polarization of M2 macrophages. Preclinical mouse xenograft experiments demonstrated a delay in tumor growth following treatment with Antrocin. These results suggest that Antrocin, identified through computational screening and validated experimentally, could be a promising multi-target agent to overcome therapy resistance in CRC. Full article

Terpenes, the largest class of plant specialized products, are built from C5 building blocks via terpene synthases and oxidized by cytochrome P450 enzymes (CYPs) for structural diversity. In some cases, CYPs do not simply oxidize the terpene backbone, but induce backbone rearrangements, methyl group shifts, and carbon–carbon (C–C) scissions. Some of these reactions were characterized over 25 years ago, but most of them were reported in recent years, indicating a highly dynamic research area. These reactions are involved in mono-, sesqui-, di- and triterpene metabolism and provide key catalytic steps in the biosynthesis of plant hormones, volatiles, and defense compounds. Many commercially relevant terpenoids require such reaction steps in their biosynthesis such as triptonide (rodent pest management), secoiridoids (flavor determinants), as well as ginkgolides, cardenolides, and sesquiterpene lactones with pharmaceutical potential. Here, we provide a comprehensive overview of the underlying mechanisms. Full article

The 1,3-dipolar cycloaddition reaction was applied to 9α-hydroxyparthenolide, an important sesquiterpene component of Anvillea radiata that was extracted directly from plant material collected in Morocco. Several new spiro-isoxazolidine derivatives were generated on the B-ring of 9α-hydroxyparthenolide (α-methylene-γ-butyrolactone (1)) by 1,3-dipolar cycloaddition of its exocyclic double bond with various nitrones. These compounds were fully characterized by spectroscopic methods. Full article

Objectives: Multiple myeloma and acute myeloid leukemia are severe forms of blood cancer, which lack effective therapies for treatment. In our search for new chemical lead structures from nature, we were investigating the Brazilian medicinal plant arnica-do-cerrado (Lychnophora ericoides). Methods: Repeated chromatography led to the isolation of four flavonoids and three sesquiterpenoids, which were evaluated for their cytostatic and cytotoxic properties against HL-60, MOLM-13, AMO-1, and KMS-12 PE cancer cells as well as the non-malignant HS-5 cell line. Results: Whereas the isolated flavonoids displayed only moderate activity, the three sesquiterpene lactones goyazensolide, centratherin, and lychnopholide exhibited pronounced effects against all four tested cell lines. Goyazensolide was the most effective compound, inhibiting proliferation and metabolic activity with IC₅₀ values between 1.0 and 1.6 µM, as well as 1.0 to 2.0 µM, respectively. Centratherin and lychnopholide were somewhat less active but showed higher selectivity towards malignant cell lines, which was most pronounced for MOLM-13 cells. Conclusion: The results of this study revealed interesting natural products that will be further evaluated for their potential as new lead compounds for the treatment of acute myeloid leukemia and multiple myeloma. Full article

Helicobacter pylori, a spiral-shaped bacterium found in the stomach, is associated with various gastrointestinal and systemic health conditions. Effective suppression of H. pylori is therefore critical for managing gastrointestinal diseases. In a search for natural products with anti-H. pylori activity, the extract of Atractylodes macrocephala rhizoma showed significant inhibitory effects. Chromatographic purification of A. macrocephala extract yielded thirteen compounds, which were identified as ten sesquiterpenes and three polyacetylenes by spectroscopic analysis. The sesquiterpene compounds belong to the eudesmane or eudesmane lactone types and exhibited structure-dependent efficacy. The major eudesmane lactone sesquiterpene, atractylenolide I (1), showed strong inhibitory activity comparable to metronidazole, a positive control, and atractylenolide III (3) also showed good efficacy. However, structural modification such as hydroxylation, methylation, or acetylation of the sesquiterpenes led to reduced activity. In contrast, polyacetylene derivatives displayed only mild inhibitory effects. Further evaluation of the active compounds against three H. pylori strains such as 51, 43504, and 26695 showed that atractylenolide I (1) had potent inhibitory effects against all three strains, with MIC₅₀ values of ranging from 27.3 to 48.6 μM and MIC₉₀ values from 45.4 to 87.2 μM. Atractylenolide III (3) exhibited selective activity against strain 51 with MIC₅₀ value of 89.9 μM. Both compounds also exhibited anti-inflammatory activity with IC₉₀ values of 23.3 and 31.1 μM, respectively, although they showed little effect on urease. This is the first report on the anti-H. pylori efficacy of various constituents of A. macrocephala and comparative analysis of inhibitory effects against several strains, which will provide scientific evidence supporting its potential as therapeutic agent for H. pylori-related infection. Full article

Tanacetum parthenium (Asteraceae) has been traditionally used worldwide for medicinal purposes, and some of its therapeutic uses have been attributed to the pharmacological effects of its secondary metabolites. The root culture of this species might represent a sustainable source of several pharmacologically active compounds. The biomass of a root T. parthenium culture was extracted with methanol and fractionated using column chromatography. Three selected fractions (4TP, 5TP, and 8TP) were analyzed via spectrophotometric, chromatographic, and mass spectrometry techniques and in vitro pharmacological assays. The greatest values for total phenolic and phenolic acid contents and antibacterial activity against Escherichia coli were determined for 4TP. The highest values for total flavonoid and sesquiterpene lactone contents, antioxidant potential, and α-amylase inhibitory effect were determined for 8TP. The antibacterial effect against Staphylococcus aureus was not significantly different among the three fractions. The root culture of T. parthenium is a potential source of several metabolites, such as phenolic acids, fatty acids, coumarins, sesquiterpenoids, and triterpenoids, which are capable of exerting α-amylase inhibition and antioxidant, antibacterial, and cytotoxic effects. Among eight phenolic compounds detected and quantified in the fractions, chlorogenic acid was the most abundant. Full article

Cichorium intybus L. (common chicory) is a medicinal plant valued for health-promoting effects. Although analgesic properties are known for chicory sesquiterpenes, the effects of extracts need yet to be explored. This study aimed to evaluate for the first time the analgesic effect (against nociceptive pain) of the root extract from C. intybus var. foliosum. The target evaluation was preceded by toxicity tests in vivo and phytochemical standardization of root extracts prepared with different extraction methods—pectinase-assisted, pressure-assisted, and a combination of both—to choose the most effective one. The phytochemical profiling involved UHPLC-PDA-ESI-MS/MS and UHPLC-PDA analyses. The toxicity and the analgesic effects were tested in mice following the OECD 423 guideline and the hot-plate test, respectively. The highest recovery of bioactive compounds was achieved for the pressure-assisted extract: 642.5 mg sesquiterpene lactones, 187.1 mg phenolic acids, and 47.3 g inulin/100 g of dry matter. The extract showed no toxic effects at the oral dose of 2000 mg/kg body weight, including no histopathologic changes, in mice within two weeks (GHS Category 5/Uncategorized). The maximum analgesic effect (MAE) of the extract at 600 mg/kg was 6.75% for rearing and 13.7% for jumping, with the impact on the nocifensive reactions not differing significantly from those of paracetamol at 60 mg/kg. Despite the relatively low effects at 600 mg/kg, the verified safety and abundance of active compounds encourage further studies on the extract and its active fractions as potential approaches to complementary pain therapy, with special concern for their mechanisms of action. Full article