Search Results (913)

The ability of the neuropeptide oxytocin to affect glial cell function is receiving increasing attention. We previously reported that oxytocin at a low nanomolar concentration could inhibit both astrocytic Ca²⁺ signals and glutamate release. Here, we investigate the ability of oxytocin receptors to couple both inhibitory and stimulatory pathways in astrocytes, as already reported in neurons. We assessed the effects of oxytocin at concentrations ranging from low to high in the nanomolar range on intracellular Ca²⁺ signals and on the glutamate release in astrocyte processes freshly prepared from the striatum of adult rats. Our main findings are as follows: oxytocin could induce dual responses in astrocyte processes, namely the inhibition and facilitation of both Ca²⁺ signals and glutamate release; the inhibitory and the facilitatory response appeared dependent on activation of the G_i and the G_q pathway, respectively; both inhibitory and facilitatory responses were evoked at the same nanomolar oxytocin concentrations; and the biased agonists atosiban and carbetocin could duplicate oxytocin’s inhibitory and facilitatory response, respectively. In conclusion, due to the coupling of striatal astrocytic oxytocin receptors to different transduction pathways and the dual effects on Ca²⁺ signals and glutamate release, oxytocin could also play a crucial role in neuron–astrocyte bi-directional communication through a subtle regulation of striatal glutamatergic synapses. Therefore, astrocytic oxytocin receptors may offer pharmacological targets to regulate glutamatergic striatal transmission, which is potentially useful in neuropsychiatric disorders and in neurodegenerative diseases. Full article

Objectives: To investigate the efficacy and underlying mechanisms of IBCar’s biological activity in breast cancer models, both in cell culture and in mice, and to compare its effects on cancer versus normal cells. Methods: The cytotoxicity of IBCar was evaluated using the MTS assay to assess metabolic activity and the clonogenic assay to determine reproductive integrity. The impact of IBCar on microtubule integrity, mitochondrial function, and multiple signaling pathways was analyzed using Western blotting, microarray analysis, and live cell imaging. The therapeutic effectiveness of orally administered IBCar was assessed in a transgenic mouse model of Luminal B breast cancer and in mice implanted with subcutaneous triple-negative breast cancer xenografts. Results: IBCar demonstrated potent cytotoxicity across a diverse panel of breast cancer cell lines, including those with mutant or wild-type TP53, and cell lines with short and long doubling times. Comparative analysis revealed distinct responses between normal and cancer cells, including differences in IBCar’s effects on the mitochondrial membrane potential, endoplasmic reticulum stress and activation of cell death pathways. In breast cancer cells, IBCar was cytotoxic at nanomolar concentrations, caused irreversible microtubule depolymerization leading to sustained mitochondrial dysfunction, endoplasmic reticulum stress, and induced apoptosis. In normal cells, protective mechanisms included reversible microtubule depolymerization and activation of pro-survival signaling via the caspase-8 and riptosome pathways. The therapeutic potential of IBCar was confirmed in mouse models of Luminal B and triple negative BC, where it exhibited strong antitumor activity without detectable toxicity. Conclusions: These findings collectively support IBCar as a promising, effective, and safe therapeutic candidate for breast cancer treatment. Full article

Platelets play critical roles in haemostasis and thrombosis. The platelet activation process is driven by agonist-induced rises in cytosolic [Ca²⁺]_i, where the patterns of Ca²⁺ responses are still incompletely understood. In this study, we developed a number of techniques to model the [Ca²⁺]_i curves of platelets from a single blood donor. Fura-2-loaded platelets were quasi-simultaneously stimulated with various agonists, i.e., thrombin, collagen, or CRP, in the presence or absence of extracellular Ca²⁺ entry, secondary mediator effects, or Ca²⁺ reuptake into intracellular stores. To understand the calibrated time curves of [Ca²⁺]_i rises, we developed two non-linear models, a multilayer perceptron (MLP) network and an autoregressive network with exogenous inputs (NARX). The trained networks accurately predicted the [Ca²⁺]_i curves for combinations of agonists and inhibitors, with the NARX model achieving an R² of 0.64 for the trend prediction of unforeseen data. In addition, we used the same dataset for the construction of a partial least square (PLS) linear regression model, which estimated the explained variance of each input. The NARX model demonstrated that good fits could be obtained for the nanomolar [Ca²⁺]_i curves modelled, whereas the PLS model gave useful interpretable information on the importance of each variable. These modelling results can be used for the development of novel platelet [Ca²⁺]_i-inhibiting drugs, such as the drug 2-aminomethyl diphenylborinate, blocking Ca²⁺ entry in platelets, or for the evaluation of general platelet signalling defects in patients with a bleeding disorder. Full article

Oximes have been reported to exhibit useful pharmaceutical properties, including compounds with anticancer, anti-arthritis, antibacterial, and neuroprotective activities. Many oximes are kinase inhibitors and have been shown to inhibit various kinases. Herein, a panel of oxime derivatives of tricyclic isatins was synthesized and evaluated for inhibition of cellular inflammatory responses and binding affinity to several kinases. Compounds 5a and 5d (a.k.a. NS-102), which have an unsubstituted oxime group, inhibited lipopolysaccharide (LPS)-induced nuclear factor-κB/activating protein 1 (NF-κB/AP-1) transcriptional activity in human THP-1Blue monocytic cells and interleukin-6 (IL-6) production in human MonoMac-6 monocytic cells, with IC₅₀ values in the micromolar range. These compounds also inhibited LPS-induced production of several other proinflammatory cytokines, including IL-1α, IL-1β, monocyte chemoattractant protein-1 (MCP-1), and tumor necrosis factor (TNF) in MonoMac-6 cells. Compounds 5a and 5d exhibited nanomolar/submicromolar binding affinity toward several kinase targets. The most potent inhibitor, 5d (3-(hydroxyimino)-5-nitro-1,3,6,7,8,9-hexahydro-2H-benzo[g]indol-2-one), demonstrated high binding affinity for 12 kinases, including DYRK1A, DYRK1B, PIM1, Haspin, HIPK1-3, IRAK1, NEK10, and DAPK1-3. Molecular modeling suggested modes of binding interaction of selected compounds in the DYRK1A and PIM1 catalytic sites that agreed with the experimental binding data. Our results demonstrate that tricyclic isatin oximes could be potential candidates for developing anti-inflammatory drugs with neuroprotective effects for treating neurodegenerative diseases. Full article

Multiple myeloma (MM) is an incurable malignancy of plasma cells that accounts for 10% of all haematological malignancies diagnosed worldwide. The poor outcome of patients with MM highlights the ongoing need for novel treatment strategies. Ferroptosis is a recently characterised form of non-apoptotic programmed cell death. Phospholipids (PLs) containing polyunsaturated fatty acids (PUFAs) play a crucial role as ferroptosis substrates when oxidised to form toxic lipid reactive oxygen species (ROS). Using a range of scientific techniques, we demonstrate a strong correlation between the PL profile of MM and diffuse large B cell lymphoma (DLBCL) cells with their sensitivity to ferroptosis. Using this PL profiling, we manufacture liposomes that are themselves composed of PL-PUFA ferroptosis substrates relatively deficient in MM cells, with and without the GPX4 inhibitor, RSL3, for investigation of their ferroptosis-inducing potential. PL-PUFAs were more abundant in DLBCL than MM cell lines, consistent with greater ferroptosis sensitivity. In contrast, MM cells generally contained a significantly higher proportion of PLs containing monounsaturated fatty acids. Altering the lipid composition of MM cells through exogenous supplementation with PL-PUFAs induced ferroptosis-mediated cell death and further sensitised these cells to RSL3. Liposomes predominantly comprising PL-PUFAs were subsequently manufactured and loaded with RSL3. Uptake, cytotoxicity and lipid ROS studies demonstrated that these novel liposomes were readily taken up by MM cells. Those containing RSL3 were more effective at inducing ferroptosis than empty liposomes or free RSL3, resulting in IC₅₀ values an average 7.1-fold to 14.5-fold lower than those for free RSL3, from the micromolar to nanomolar range. We provide a better understanding of the mechanisms associated with ferroptosis resistance of MM cells and suggest that strategies such as liposomal delivery of relatively deficient ferroptosis-inducing PL-PUFAs together with other targeted agents could harness ferroptosis for the personalised treatment of MM and other cancers. Full article

A single domain antibody (SDAb) targeting canine PD-1 was developed as a potential immunotherapeutic for canine cancer. An alpaca was immunized with canine PD-1 protein, and a phage-display library was constructed using mRNA isolated from peripheral lymphocytes. Screening of the library yielded multiple SDAb candidates capable of nanomolar binding to canine PD-1. Among these, clone STX-1b5 demonstrated high expression in a yeast-based recombinant system and was selected for further characterization. Binding and competition assays using ELISA confirmed its ability to bind canine PD-1 and block PDL-1 interaction. In silico structural modeling supported the interaction of STX-1b5 with key PD-1 residues implicated in ligand binding. These findings support the feasibility of using SDAbs and cost-effective yeast expression systems to generate immunotherapeutics for veterinary use, with STX-1b5 representing a promising lead candidate for future clinical development. Full article

Background/Objectives: Human carbonic anhydrases (hCAs) are metalloenzymes involved in essential physiological processes, and their selective inhibition holds therapeutic potential across a wide range of disorders. However, the high degree of structural similarity among isoforms poses a significant challenge for the design of selective inhibitors. In this work, we present a machine learning (ML)-based platform for the isoform-specific prediction and profiling of small molecules targeting hCA I, II, IX, and XII. Methods: By integrating four molecular representations with four ML algorithms, we built 64 classification models, each extensively optimized and validated. The best-performing models for each isoform were applied in a virtual screening campaign for ~2 million compounds. Results: Following a multi-step refinement process, 12 candidates were identified, purchased, and experimentally tested. Several compounds showed potent inhibitory activity in the nanomolar to submicromolar range, with selectivity profiles across the isoforms. To gain mechanistic insights, SHAP-based feature importance analysis and molecular docking supported by molecular dynamics simulations were employed, highlighting the structural determinants of the predicted activity. Conclusions: This study demonstrates the effectiveness of integrating ML, cheminformatics, and experimental validation to accelerate the discovery of selective carbonic anhydrase inhibitors and provides a generalizable framework for activity profiling across enzyme isoforms. Full article

Toxicological studies of pesticides in animal models provide critical insights into their mechanisms of action, while adsorption strategies offer potential solutions for decontaminating polluted waters. We evaluated toxicity induced by tetraethyl pyrophosphate (TEPP), an organophosphate pesticide and AChE inhibitor, on zebrafish (Danio rerio) development and behavior, alongside the efficacy of wine cork granules as a natural adsorbent. TEPP exposure reduced embryo viability following an inverted U-shaped dose–response curve, suggesting non-monotonic neurodevelopmental effects, but did not alter developmental timing or morphology in survivors. In juveniles, TEPP increased preference for dark environments (33% vs. controls) and enhanced swimming endurance approximately 3-fold, indicating disrupted phototaxis and stress responses. Most strikingly, water treated with cork granules retained toxicity, increasing mortality, delaying embryogenesis, and altering behavior. This directly contradicts in vitro adsorption studies that suggested cork’s efficacy. These results demonstrate the high sensitivity of zebrafish to TEPP at nanomolar concentrations, which contrasts with in vitro models that require doses approximately 1000 times higher. Our findings not only highlight TEPP’s ecological risks but also reveal unexpected limitations of cork granules for environmental remediation, urging caution in their application. Full article

In this study, gold nanoparticles (AuNPs) and AuNPs-graphene oxide (AuNPs@GO) nanostructures were synthesized in aqueous media using an in-situ photochemical method with bis-acyl phosphine oxide (BAPO) photoinitiator as a photoreducing agent in the presence of HAuCl₄. The parameters for synthesis were arranged to obtain stable and reproducible dispersions with desirable chemical and optical properties. Both AuNPs and AuNPs@GO were employed as sensing platforms for the detection of epinephrine in two concentration ranges: micromolar (µM) and nanomolar (nM). Field emission scanning electron microscopy (FE-SEM), Dynamic Light Scattering (DLS), UV-Vis absorption, fluorescence emission, and Fourier Transform Infrared (FT-IR) spectroscopy techniques were used to investigate the morphological, optical, and chemical properties of the nanostructures as well as their sensing ability towards epinephrine. Fluorescence spectroscopy played a crucial role in demonstrating the high sensitivity and effectiveness of these systems, especially in the low concentration (nM) range, confirming their strong potential as fluorescence-based sensors. By constructing calibration curves on best linear subranges, limit of detection (LOD) and limit of quantification (LOQ) were calculated with two different approaches, SE_intercept and S_y/x. Among all the investigated nanostructures, AuNPs@GO exhibited the highest sensitivity towards epinephrine. The efficiency and reproducibility of the in-situ photochemical AuNPs synthesis approach highlight its applicability in small-molecule detection and particularly in analytical and bio-sensing applications. Full article

Chronic pain affects a significant portion of the population, with fewer than 30% achieving adequate relief from existing treatments. This study describes the humanization methodology and characterization of an effective non-opioid single-chain fragment variable (scFv) biologic that reverses pain-related behaviors, in this case by targeting P2X4. After nerve injury, ATP release activates/upregulates P2X4 receptors (P2X4R) sequestered in late endosomes, triggering a cascade of chronic pain-related events. Nine humanized scFv (hscFv) variants targeting a specific extracellular 13-amino-acid peptide fragment of human P2X4R were generated via CDR grafting. ELISA analysis revealed nanomolar binding affinities, with most humanized molecules exhibiting comparable or superior affinity compared to the original murine antibody. Octet measurements confirmed that the lead, HC3-LC3, exhibited nanomolar binding kinetics (KD = 2.5 × 10⁻⁹ M). In vivo functional validation with P2X4R hscFv reversed nerve injury-induced chronic pain-related behaviors with a single dose (0.4 mg/kg, intraperitoneal) within two weeks. The return to naïve baseline remained durably reduced > 100 days. In independent confirmation, the spared nerve injury (SNI) model was similarly reduced. This constitutes an original method whereby durable reversals of chronic nerve injury pain, anxiety and depression measures are accomplished. Full article

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with enhanced transmissibility and immune evasion underscores the urgent need for broad-spectrum antiviral therapeutics. In this study, we strategically engineered a novel dual-targeting peptide inhibitor, R1L25HR2, by conjugating the receptor-binding domain (RBD)-targeting peptide R1 with the heptad repeat 1 (HR1)-targeting peptide HR2 through an optimized 25-mer flexible linker (GGGGS)5, aiming to simultaneously block viral attachment and membrane fusion. R1L25HR2 potently and broadly inhibits the infection of SARS-CoV-2 and its emerging variants, including recent circulating strains JN.1 and KP.2, with IC₅₀ values ranging from 5.3 to 253.5 nM, which is significantly more effective than HR2 and R1 alone. Mechanistically, R1L25HR2 inhibits viral attachment and membrane fusion by binding to both RBD and HR1 with low nanomolar affinity. These results highlight the innovative strategy of dual-targeting the RBD and HR1 domains as an effective approach to overcome viral resistance and achieve broad-spectrum antiviral activity. Full article

Ovarian cancer (OC) is the most lethal gynecologic malignancy worldwide, with high rates of disease relapse posing a significant therapeutic challenge. Consequently, there is an urgent need to develop novel treatments for OC. This study aims to evaluate the effects of the novel imipridone, ONC206, both as a monotherapy and in combination with the standard of care chemotherapy drug, cisplatin (CDDP), on human OC cell lines. In order to study the effect of ONC206 and CDDP on ovarian cancer, two cell lines, OVCAR-420 and SKOV-3, were used in this study. Cell proliferation was assessed using MTT assay while cell viability was evaluated using the trypan blue exclusion assay. Cell migration was examined using the wound healing assay. To investigate the effects of both treatments, alone or in combination on the stem-cell-like population of OC cells, the sphere-forming assay was employed. Our results revealed that ONC206, alone or in combination with CDDP, exerts a potent anti-proliferative effect on both OVCAR-420 and SKOV-3 cells, as shown in the MTT and trypan blue exclusion assays. Interestingly, a synergistic effect was observed when ONC206 was combined with CDDP, enhancing the overall anti-cancer efficacy. Additionally, ONC206 alone or in combination with CDDP inhibited the migratory ability of the ovarian cancer cells. Furthermore, the activity of ovarian cancer stem cells was inhibited when cells were treated with ONC206 alone or in combination with CDDP, as shown in the significant decrease in both the size and the sphere-forming ability of ovarian cancer stem cells in the 3D culture model. Our results highly suggest the potential of imipridones as a new class of therapeutics in ovarian cancer management. Among these, ONC206 shows nanomolar potency, highlighting its potential as a standalone therapy or in combination with existing treatment regimens. Full article

Background: Food safety remains a global concern due to biological and chemical contaminants, including adulterants, pathogens, antibiotic residues, and pesticides. Traditional detection methods are accurate but limited by time requirements, complex sample preparation, high costs, and poor field applicability. Surface-Enhanced Raman Spectroscopy (SERS) offers non-destructive analysis with low detection limits and high specificity, yet conventional SERS substrates face challenges with reproducibility, nanoparticle aggregation, and sensitivity in food matrices. Hydrogels have emerged as supporting materials for SERS due to their water content, tunable porosity, flexibility, and ability to entrap plasmonic nanostructures. Scope and Approach: This review examines recent advances in hydrogel-integrated SERS platforms for food safety applications. The three-dimensional structure of hydrogels enables homogeneous distribution of metal nanoparticles, prevents aggregation, and offers analyte enrichment. We analyze material design, functionalization strategies, and how hydrogel properties—crosslinking density, porosity, surface charge, and nanoparticle distribution—influence SERS performance in food matrices. Key Findings and Conclusions: Hydrogel-integrated SERS platforms demonstrate superior performance in detecting various food contaminants—including pesticides, adulterants, and additives—in real food matrices, often achieving detection limits in the nanomolar to picomolar range, depending on the analyte and substrate design. Current limitations include storage stability concerns, batch-to-batch variability, and regulatory acceptance hurdles. Future research directions should focus on multiplex detection capabilities, integration with smart sensing technologies, and industrial scalability to facilitate practical deployment in global food safety monitoring across diverse supply chains. Full article

Background/Objectives: Colony stimulating factor 1 receptor kinase (CSF1R) is a well-validated molecular target in drug discovery for various reasons. Based on the structure of an early lead molecule identified in our lab and the marketed drug Pexidartinib (PLX3397), we merged fragments of Pexidartinib with our pyrrolo[2,3-d]pyrimidine nucleus, and the idea was supported by initial molecular docking studies. Thus, several new compounds were synthesized with Pexidartinib fragments on C4, C5, and C6 on the pyrrolopyrimidine scaffold using molecular hybridization. Methods: Nine final products were synthesized using a combination of Buchwald-Hartwig and Suzuki-Miyaura cross-coupling reactions in three to four steps and in good yields. The analogues were subsequently profiled as CSF1R inhibitors in enzymatic and cellular assays, and ADME properties were evaluated for some derivatives. Results: N-Methyl-N-(3-methylbenzyl)-6-(6-((pyridin-3-ylmethyl)amino)pyridin-3-yl)-7H-pyrrolo[2,3-d]pyrimidin-4-amine (12b) emerged as the most potent CSF1R inhibitor, showing low-nanomolar enzymatic activity, cellular efficacy, and favorable ADME properties, highlighting its promise as a lead compound for further development. Conclusions: These findings suggest that combining structural elements from previously reported CSF1R inhibitors such as Pexidartinib could guide the development of improved drug candidates targeting this kinase. Full article

Optical–chemical sensors based on optical fibers can be made in reflection or transmission schemes. In the reflection scheme, the sensing area is typically present at the end of the fiber, and the light source and the detector are placed on the same side of the fiber. This approach can be exploited to achieve chemical probes useful in several application fields where remote sensing is required. In this work, to obtain an extrinsic optical fiber chemical sensor in a reflection scheme, two optical fibers are used to monitor a chemically sensitive region achieved by a C-shaped waveguide with a molecularly imprinted polymer (MIP) as a core between the optical fibers. The proposed micrometer-sized probe is developed and tested as a proof of concept via a MIP for 2-Furaldehyde (2-FAL) detection of interest in food and industrial applications. The experimental results of the proposed sensing approach showed several advantages, such as a nanomolar detection limit and an ultra-wide concentration detection range due to different kinds of MIP recognition sites in the optical path between the fibers. Full article