Search Results (27,956)

Modern medicine requires effective, continuous, and safe therapies, which largely depend on the targeted delivery and activity of the drug. This goal can be achieved by designing drug delivery systems with improved pharmacokinetic properties and enhanced drug transport to the affected tissue. Human serum albumin (HSA) is an attractive carrier for the synthesis of therapeutic nanoparticles, several of which have already been approved by the United States Food and Drug Administration (FDA). The success of Abraxane as an effective treatment for metastatic breast cancer and non-small cell lung carcinoma, the application of Optison in ultrasound imaging, and the use of Nanocoll as an agent for SPECT diagnostics in sentinel node localisation confirm the strong potential of albumin-based systems. Further benefits are expected in patients with soft tissue cancers, as LadRx is seeking FDA marketing approval for Aldoxorubicin. The future of oncology lies in theranostics, which combines a tumour-localising factor on one platform with a drug targeting cancer cells and a factor that activates the cytotoxicity of the drug after it reaches the target tissue. This article presents recent advancements in albumin-based nanoparticles for drug delivery, targeting, and imaging. It also briefly discusses methods of synthesis and surface modification of albumin nanocarriers to enable targeted delivery to pathological sites. Finally, it outlines the latest approaches in multimodal theranostic platforms, highlighting albumin’s potential to improve cancer therapy. Full article

Background/Objectives: The development of specific inhibitors for cyclooxygenase-2 (COX-2) is a challenge for public health. A series of 17 N-phthalimide hybrids was evaluated using a functional M06 meta-GGA hybrid in combination with a polarized 6-311G (d, p) basis set. The top three candidates (6, 10, and 17) were synthesized and evaluated as selective COX-2 inhibitors of PGE-2 using an integrated in silico–in vitro approach. Methods: Molecular docking against COX-2 (PDB 5KIR) and COX-1 (PDB 6Y3C), supported by homology modeling and DFT geometry optimization (B3LYP/6-31G*), revealed that the phthalimide carbonyl groups and the 3,4,5-trimethoxyphenyl or geranyl-derived moieties establish key hydrogen bonds and hydrophobic contacts with Arg120, Tyr355, Tyr385, and Ser530 in the COX-2 active site, conferring predicted selectivity ΔGCOX−2 vs. COX−1 = −1.4 to −2.8 kcal/mol. Results: The compounds complied with Lipinski’s and Veber’s rules and displayed favorable ADMET profiles. In vitro assessment in LPS-stimulated J774A.1 murine macrophages confirmed potent inhibition of PGE₂ production, 3.05 µg/mL, with compound 17 exhibiting the highest efficacy, 97.79 ± 5.02% inhibition at 50 µg/mL, and 10 showing 95.22 ± 6.03% inhibition at 50 µg/mL. Notably, all derivatives maintained >90% cell viability up to 250 µg/mL by resazurin assay and showed no evidence of cytotoxicity or mitosis potential in the tests at 24 h. Conclusions: These results demonstrate that strategic hybridization of phthalimide with natural and synthetic product-derived fragments yields highly potential PGE2 inhibitors. Therefore, compounds 6, 10, and 17 are promising lead candidates for the development of safer anti-inflammatory agents. Full article

Background: Trypanosoma cruzi, the causative agent of Chagas disease, remains a major public health concern, and there is a continued need for new antitrypanosomal agents. Thiosemicarbazone (TSC) derivatives have emerged as a promising class of compounds with potential antiparasitic activity. Objectives: This study aimed to report the synthesis, characterization, and biological profiling of a novel series of thiosemicarbazone derivatives as antitrypanosomal agents against Trypanosoma cruzi. Methods: Fourteen new compounds and six previously described analogues were prepared and characterized by ¹H/¹³C nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS). As a preliminary in vitro screen, activity was assessed by direct parasite counting in epimastigote and bloodstream trypomastigote forms, as tractable models of replicative and infective stages sharing core metabolic targets with intracellular amastigotes. Epimastigote potency was quantified as half-maximal effective concentrations (EC₅₀) derived from dose–response curves, whereas trypomastigote response was evaluated as percent viability after treatment at a fixed concentration of 20 µM. Mechanistic profiling included inhibition assays against the cysteine protease cruzipain (CZP) and selected redox defense enzymes, complemented by in silico similarity clustering and binding-pose affinity scoring. Results: A nitro-methoxy-substituted TSC showed potent CZP inhibition but limited trypomastigote efficacy, whereas brominated analogues displayed dual-stage activity independent of CZP inhibition. Tanimoto similarity analysis identified distinct structure–activity clusters, linking nitro-methoxy substitution to epimastigote selectivity and brominated scaffolds to broader antiparasitic profiles, with hydrophobicity and steric complementarity as key determinants. Enzymatic assays revealed no significant inhibition of cytosolic tryparedoxin peroxidase (cTXNPx) or glutathione peroxidase type I (TcGPx-I), suggesting redox disruption is not a primary mode of action. In vitro and in silico analyses showed low or no non-specific cytotoxicity under the tested conditions, supporting further optimization of these derivatives as antitrypanosomal preliminary hits. Key hits included derivative 3e (epimastigote EC₅₀ = 0.36 ± 0.02 µM) and brominated analogues 2c and 2e (epimastigote EC₅₀ = 3.92 ± 0.13 and 4.36 ± 0.10 µM, respectively), while docking supported favorable binding-pose affinity (e.g., ΔG_S-pose = −20.78 ± 2.47 kcal/mol for 3e). Conclusions: These results support further optimization of the identified thiosemicarbazone derivatives as preliminary antitrypanosomal hits and provide insight into structure–activity relationships and potential mechanisms of action. Full article

Background: Heterocyclic compounds are particularly important in medicinal chemistry. With a range of therapeutic uses, benzimidazoles and quinolines are both key heterocycles in medicinal chemistry. A number of hybrid heterocyclic compounds have been reported in recent years because they typically have better therapeutic properties than single heterocyclic rings. Methods: A literature search was conducted across relevant scientific literature from peer-reviewed sources, using keywords, including “benzimidazole”, “quinoline”, “benzimidazole-quinoline hybrids”, “antibacterial”, “antifungal”, “antimalarial” and “hybrid complexes”. Results: This review summarizes the synthetic methodologies for benzimidazole–quinoline hybrids, benzimidazole– quinolinones, and benzimidazole–quinoline metal complexes, along with their antimicrobial and antimalarial activities and the reported structure–activity relationship (SAR) studies. The importance of halogen substitution, particularly with chlorine and fluorine atoms, as well as the structure of the linker between the benzimidazole and quinoline rings—specifically chain length, the presence of oxygen, sulfur, or nitrogen atoms, and heterocyclic moieties—is highlighted. A series of benzimidazole–quinoline hybrids exhibit antimalarial and antitrypanosomal activities or show enhanced antimicrobial properties due to the incorporation of a five-membered heterocycle in addition to the two existing heterocyclic rings. Notably, several hybrids from different compound series exhibit very low minimum inhibitory concentrations (MICs) in the range of 1–8 µg/mL, along with low cytotoxicity, supporting their potential for further investigation as antimicrobial agents. Conclusions: This review summarizes the synthetic methods, medicinal properties, and structure–activity relationship (SAR) studies of benzimidazole–quinoline hybrids reported between 2002 and 2026. Full article

The threat of antimicrobial resistance (AMR) and the need for sustainable disinfectants have spurred interest in natural antimicrobials such as essential oils (EOs). However, their application is limited by volatility, poor water solubility, and cytotoxicity. Herein, we present the development of bio-based core–shell sub-micro-/nanocapsules (NCs) with encapsulated oregano (OO), thyme (TO), eucalyptus (EuO), and tea tree (TTO) oils to enhance antimicrobial (AM) performance and reduce cytotoxicity. NCs were synthesized via a nanoencapsulation method using chemically modified zein or poly(methyl vinyl ether-co-maleic anhydride) (GZA) as shell polymers, with selected EOs encapsulated in their core (encapsulation efficacy > 98%). Chemical modification of zein with vanillin (VA) and GZA with either dodecyl amine (DDA) or 3-(glycidyloxypropyl)trimethoxysilane (EPTMS) resulted in improvement in particle size distributions, polydispersity indices (PDIs) of synthesized NCs, and in the stability of the NC-dispersions in water. Antibacterial testing against Staphylococcus aureus and cytotoxicity assays showed that encapsulation significantly reduced toxicity while preserving their antibacterial activity. Among the formulations, GZA-based NCs modified with EPTMS provided the best balance between safety and efficacy. Despite this, life cycle assessment revealed that zein-based NCs were more environmentally sustainable due to lower energy use and material impact. Overall, the approach offers a promising strategy for developing sustainable, effective, and safe EO-based antibacterial agents for AM applications. Full article

The Transient Receptor Potential Ankyrin 1 (TRPA1) channel is a non-selective cation channel activated by a range of physical and chemical stimuli. While primarily studied in neuronal tissues, TRPA1 is also expressed in human keratinocytes, where its role remains poorly understood. Here, we investigated TRPA1 expression and function in keratinocytes and examined the effects of its activation on cellular proliferation, immune activation, and neuropeptide release under both basal and inflammatory stimuli. TRPA1 expression was detected in basal keratinocytes and was upregulated by pro-inflammatory cytokines. Stimulation with the TRPA1 agonist allyl isothiocyanate (AITC) induced a rapid calcium influx, confirming functional channel activity. AITC at 5 µM did not induce cytotoxicity but significantly reduced keratinocyte proliferation and caused cell cycle arrest. Under stimulation with TNF-α and IFN-γ, TRPA1 activation decreased the surface expression of HLA-DR and ICAM-1, and downregulated mRNA levels of CXCL10, CXCL8, CCL5, and CCL20, while IL-6 expression remained unchanged. Furthermore, AITC treatment reduced the secretion of Substance P, but not CGRP. These findings indicate that TRPA1 functions as a cytokine-inducible, immunomodulatory receptor in human keratinocytes, capable of attenuating proliferation and inflammatory activation without compromising cell viability, thereby suggesting a potential role in maintaining skin homeostasis and modulating cutaneous inflammation. Full article

Actinium-225 (²²⁵Ac) has emerged as a pivotal alpha-emitter in modern radiopharmaceutical therapy, offering potent cytotoxicity with the potential for precise tumour targeting. Accurate, patient-specific image-based dosimetry for ²²⁵Ac is essential to optimize therapeutic efficacy while minimizing radiation-induced toxicity. Establishing a robust dosimetry workflow is particularly challenging due to the complex decay chain, low administered activity, limited count statistics, and the indirect measurement of daughter gamma emissions. Clinical single-photon emission computed tomography/computed tomography protocols with harmonized acquisition parameters, combined with robust volume-of-interest segmentation, artificial intelligence (AI)-driven image processing, and voxel-level analysis, enable reliable time-activity curve generation and absorbed-dose calculation, while reduced mixed-model approaches improve workflow efficiency, reproducibility, and patient-centred implementation. Cadmium zinc telluride-based gamma cameras further enhance quantitative accuracy, enabling rapid whole-body imaging and precise activity measurement, supporting patient-friendly dosimetry. Complementing these advances, the cerium-134/lanthanum-134 positron emission tomography in vivo generator provides a unique theranostic platform to noninvasively monitor ²²⁵Ac progeny redistribution, evaluate alpha-decay recoil, and study tracer internalization, particularly for internalizing vectors. Together, these technological and methodological innovations establish a mechanistically informed framework for individualized ²²⁵Ac dosimetry in targeted alpha therapy, supporting optimized treatment planning and precise response assessment. Continued standardization and validation of imaging, reconstruction, and dosimetry workflows will be critical to translate these approaches into reproducible, patient-specific clinical care. Full article

Chalcones have garnered significant research interest due to their various medical bioactivities. Several chalcone compounds have been approved for marketing and clinical use in the treatment of various diseases. A critical aspect of the action of chalcones is their effect on microtubules. They are considered an excellent target for chemotherapeutic agents for the treatment of cancer. Consequently, scientists are constantly developing novel chalcone drug agents and also innovative drug delivery strategies. In this manuscript, we report the first synthesis of 12 new visible-light-activated, photoswitchable chalcone-based microtubule inhibitors (17a–17l). Among the obtained compounds, one photoswitch demonstrated light-dependent cytotoxicity in the PC-3 cancer cell line. The IC₅₀ value of the Z conformer was determined to be 4.75 ± 1.00 μM after 48 h of treatment. The E conformer exhibited slightly lower activity compared to the Z conformer, with an IC₅₀ value of 5.80 ± 0.80 µM following 48 h of incubation. In this study, NMR and UV spectroscopy, along with computational methods, were employed. Full article

Nitrite, as a widely present nitrogen oxide compound in nature, and is extensively distributed in production and daily life; precise and rapid detection of it is of great significance for ensuring human health. This study developed nitrogen-doped carbon dots (N-CDs) using malic acid and 3-diethylaminophenol as precursors by one-step hydrothermal treatment. The obtained N-CDs exhibited strong green fluorescence with a high quantum yield of 20.86%. More importantly, they served as a highly effective fluorescent probe for NO₂⁻ sensing, demonstrating a low detection limit of 28.33 μM and a wide linear response range of 400 to 1000 μM. The sensing mechanism was attributed to an electrostatic interaction-enhanced dynamic quenching process. Notably, the probe enabled dual-mode detection: a distinct color change from light pink to dark brown under daylight for visual semi-quantification, and quantitative fluorescence quenching. The N-CDs showed excellent selectivity over common interfering ions. Furthermore, their low cytotoxicity and good biocompatibility allowed for successful bioimaging of exogenous and endogenous NO₂⁻ fluctuations in live HeLa cells. This work presents a facile green strategy to synthesize multifunctional N-CDs that realized the sensitive, selective, and visual detection of NO₂⁻ in environmental and biological systems. Full article

To date, neutrophil-derived myeloperoxidase (MPO), a key mediator of inflammation and oxidative stress, has predominantly been assessed in peripheral fluids by protein concentration rather than enzymatic activity, mainly due to methodological limitations. However, MPO activity directly reflects the enzyme’s cytotoxic potential and pathogenic role in inflammatory diseases. To address this gap, we employed an optimized immunocapture assay to evaluate MPO activity, specific activity, and protein concentration in females with type 2 diabetes mellitus (T2DM), a condition tightly linked to chronic low-grade inflammation and obesity. Our findings revealed that females with T2DM exhibited nearly three-fold higher serum MPO activity and more than two-fold greater specific activity compared to controls with no differences in MPO protein concentration. Notably, MPO-specific activity remained significantly associated with T2DM (p < 0.01 to p < 0.001 across multivariate models), even after adjusting for age and dual-energy X-ray absorptiometry-derived measures of total and regional fat mass. Only android/gynoid fat distribution retained marginal significance in these models. This study is the first demonstration that MPO enzymatic activity, rather than protein concentration, is independently linked to T2DM in females. These findings underscore the importance of assessing functional MPO activity in the context of metabolic disease and support its potential role as a pathophysiological marker. Full article

Background: Immune checkpoint inhibitors (ICIs), such as anti-programmed death (PD)-1 and anti-cytotoxic T-lymphocyte-associated protein (CTLA)-4 agents, have revolutionized oncology but are associated with immune-related adverse events (irAEs). Among these, ICI-associated myocarditis (ICI-M) is a rare but life-threatening complication, with mortality rates ranging from 27% to 50%. Objective: This narrative review summarizes the pathogenesis, epidemiology, clinical presentation, diagnostic methods, and management strategies for ICI-induced myocarditis, specifically highlighting emerging biomarkers and immunosuppressive therapeutic approaches. Results and Discussion: ICI-M typically presents within the first 65 days of treatment and is significantly more frequent with combination therapies. Pathologically, it is characterized by myocyte necrosis and massive infiltration of cluster of differentiation (CD)4+ and CD8+ T-cells, often overlapping with myositis (irM/M). Diagnosis relies on a multimodal approach. Management requires immediate ICI cessation and initiation of high-dose corticosteroids as first-line therapy. For steroid-refractory cases, second-line options include mycophenolate mofetil (MMF), intravenous immunoglobulin (IVIG), and emerging therapies like abatacept and ruxolitinib. Rechallenge with ICIs after high-grade ICI-M must be approached with extreme caution by the multidisciplinary team (MDT). Emerging biomarkers and omics techniques hold promise for earlier diagnosis and risk stratification. Conclusions: ICI-M is a rare yet highly lethal cardiac complication demanding high clinical vigilance and timely diagnosis. Management hinges on an aggressive multidisciplinary approach, aiming to minimize toxicity while balancing oncological efficacy. Full article

Among the metal-derived complexes, recently, tin derivatives have been investigated as promising anti-cancer drug candidates. Our previous study showed that the tin-based compound Bu₃SnOCOCF₃ (TBT) exerts cytotoxic activity on solid tumor cell lines. In the present study, the effects of TBT were evaluated in vitro on HTLV-1-infected human lymphocytic cell lines at different stages of viral transformation, consisting of IL-2-dependent (PB2/IL-2) and IL-2-independent (PB2/NO-IL-2) cells, generated in our laboratory by HTLV-1 in vitro infection of lymphocytes from the same donor, and the C91/PL cell line established by co-cultivation with T cells from a patient with HTLV-1-positive leukemia. TBT induced a reliable and reproducible dose-dependent inhibition of metabolic activity and viability in the HTLV-1-infected cells. The effect was cell-type-dependent, with C91/PL cells being quite resistant. An investigation into the cytotoxic effects induced by TBT in HTLV-1-infected cells and data on caspase inhibitors/caspase activation indicated that apoptotic cell death was involved, but also that the possible involvement of other forms of cell death could not be excluded. Taken together, the results show for the first time that the tin-based compound, although not devoid of a certain cytotoxicity toward uninfected cells, can induce typical and potent effects on HTLV-1-infected cells. Full article

Steroidal compounds lie at the crossroads of inflammation and cancer, where modulation of common signaling pathways creates opportunities for dual-action therapeutic intervention. Accumulating evidence indicates that their anti-inflammatory and antitumor activities are frequently interconnected, reflecting shared molecular mechanisms that regulate immune signaling, oxidative stress, cell proliferation, and apoptosis. This review provides a critical and comparative analysis of major classes of bioactive steroids—including furanosteroids, neo-steroids, aromatic steroids, α,β-epoxy steroids, peroxy steroids, cyanosteroids, nitro- and epithio steroids, halogenated steroids (fluorinated, chlorinated, brominated, iodinated), and steroid phosphate esters—with emphasis on their dual anti-inflammatory and anticancer potential. More than one thousand steroidal metabolites derived from plants, fungi, marine organisms, bacteria, and synthetic sources are surveyed. While the majority exhibit either anti-inflammatory or antineoplastic activity alone, only a limited subset displays potent activity in both domains. Comparative evaluation highlights the structural features that favor dual functionality, including epoxide, peroxide, nitrile, nitro, halogen, and phosphate ester moieties, as well as rearranged or heteroatom-enriched steroidal frameworks. Where available, biological data from in vitro and in vivo assays (IC₅₀ values, enzyme inhibition, cytokine modulation, and antiproliferative effects) are summarized and critically compared. Special attention is given to rare natural metabolites—such as polyhalogenated marine steroids, phosphorylated sterols, and heteroatom-containing derivatives—as well as synthetic analogues designed to enhance cytotoxic or immunomodulatory efficacy. Mechanistically, steroids exhibiting dual activity commonly modulate convergent signaling pathways, including NF-κB, JAK/STAT, MAPK, PI3K/AKT, redox homeostasis, and apoptosis regulation. Collectively, these findings underscore the potential of structurally optimized steroids as multifunctional therapeutic agents and provide a framework for the rational design of next-generation anti-inflammatory and anticancer drugs. Full article

This study evaluates and compares the protective effects of several type II taste receptor (T2R) agonists against LPS (lipopolysaccharide)-induced inflammatory damage in BEAS-2B cells, focusing on their action via an α-gustducin (encoded by GNAT3)-dependent signaling pathway that leads to NF-κB inhibition. To investigate gene expression, mRNA levels of target inflammatory cytokines and T2R subtypes were quantified by qRT-PCR. Cytotoxicity assessment of LPS and bitter agonists was conducted using the CCK-8 assay. The activation status of the NF-κB pathway was examined by Western blot analysis of total and phosphorylated forms of p65 and IκB. Finally, the specific and essential role of GNAT3 was definitively validated through siRNA-mediated gene knockdown. LPS treatment induced significant upregulation of IL-6 and IL-8 mRNA, along with increased phosphorylation of p65 and IκB in BEAS-2B cells. A direct, parallel comparison of the bitter taste agonists PTC (phenylthiourea), QN (quinine), CPD (carisoprodol), and LK (chloroquine) revealed their capacity to upregulate specific T2R subtypes, suppressing inflammatory mediator release and NF-κB activation. Critically, upon GNAT3 silencing, the inhibitory effects of all tested agonists on p-p65/p65 and p-IκB/IκB ratios were significantly attenuated, without altering total p65 or IκB abundance. This provides direct genetic evidence that GNAT3 is specifically required for mediating the anti-inflammatory effects elicited by these T2R agonists. Multiple bitter receptor agonists exert anti-inflammatory effects on airway epithelial cells in a GNAT3-dependent manner. Our study advances the field by systematically comparing agonist efficacy and establishing the indispensable role of GNAT3 within the anti-inflammatory signaling cascade triggered by T2R agonists, thereby revealing a refined mechanistic insight and potential therapeutic target for inflammatory lung diseases. Full article

Background/Objectives: The global rise in multidrug-resistant (MDR) bacteria, particularly methicillin-resistant and methicillin-susceptible Staphylococcus aureus (MRSA and MSSA), continues to pose a major public health challenge, including in Hawaii. This underscores the need to discover new antimicrobial agents from natural sources. Guided by teachings from a Buddhist master regarding the medicinal value of lichens, we investigated the endemic Hawaiian lichen Cladonia skottsbergii. Methods: Specimens of C. skottsbergii were collected from the Lotus Buddhist Monastery in Mountain View, Hawaii. A methanolic extract was prepared and purified using chromatographic techniques, and compound structures were elucidated through spectroscopic analyses and single-crystal X-ray diffraction. The antibacterial activity of the compounds was assessed against Gram-positive strains (MRSA, MSSA) and Gram-negative bacteria (Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa). Cytotoxicity was assessed using A549 (non-small cell lung cancer) and Vero E6 (non-tumorigenic) cell lines. Results: Three compounds were isolated: clarosione (1), a newly identified trichlorinated xanthone, and two known metabolites, (S)-usnic acid (2) and perlatolic acid (3). Compounds 2 and 3 demonstrated strong inhibitory effects against MRSA and MSSA. Their minimum inhibitory concentrations (MICs) ranged from 2 to 4 µg/mL, compared with vancomycin (0.5–1 µg/mL). Cytotoxicity testing showed higher sensitivity in A549 cells than in Vero E6 cells, resulting in favorable selectivity indices for the active compounds. Conclusions: In the current study, a new compound, clarosione (1) was discovered. This enhances our understanding of the constituents of C. skottsbergii and its potential antibacterial properties. Lichen-derived compounds may serve as lead candidates for further development, and further study is warranted. Full article