Search Results (1,376)

Background: Histone deacetylase 6 (HDAC6) is a unique class IIb HDAC isozyme characterized by two catalytic domains and a zinc finger ubiquitin-binding domain. It plays critical roles in various cellular processes, including protein degradation, autophagy, immune regulation, and cytoskeletal dynamics. Due to its multifunctional nature and overexpression in several cancer types, HDAC6 has emerged as a promising therapeutic target. Methods: In this study, we employed a ligand-based pharmacophore modeling approach using a structurally diverse set of known HDAC6 inhibitors. This was followed by the virtual screening of over 140,000 commercially available compounds from both the MolPort and Asinex databases. The screening workflow incorporated pharmacophore filtering, molecular docking, and molecular dynamic (MD) simulations. Binding free energies were estimated using Molecular Mechanics Generalized Born Surface Area (MM-GBSA) analysis to prioritize top candidates. A fluorometric enzymatic assay was used to measure HDAC6 activity, while cell viability assay by Cell Titer Glo was used to assess the anti-tumor activity against drug-sensitive and -resistant multiple myeloma (MM) cells. Western blotting was used to evaluate the acetylation of tubulin or histone H4 after treatment with selected compounds. Results: Three promising compounds were identified based on stable binding conformations and favorable interactions within the HDAC6 catalytic pocket. Among them, Molecular Mechanics Generalized Born Surface Area (MM-GBSA) analysis identified Compound 10 (AKOS030273637) as the top theoretical binder, with a ΔG_bind value of −45.41 kcal/mol. In vitro enzymatic assays confirmed its binding to the HDAC6 catalytic domain and inhibitory activity. Functional studies on MM cell lines, including drug-resistant variants, showed that Compound 10 reduced cell viability. Increased acetylation of α-tubulin, a substrate of HDAC6, likely suggested on-target mechanism of action. Conclusion: Compound 10, featuring a benzyl 4-[4-(hydroxyamino)-4-oxobutylidene] piperidine-1-carboxylate scaffold, demonstrates potential drug-like properties and a predicted bidentate zinc ion coordination, supporting its potential as an HDAC6 inhibitor for further development in hematologic malignancies. Full article

Adipose-derived mesenchymal stem cells (ASCs) have great potential in regenerative medicine due to their abundance and innate multi-lineage differentiation potential. However, the therapeutic efficacy of ASCs is often compromised by poor microenvironmental conditions in the damaged tissues after transplantation. In this study, we generated and assessed genetically modified ASCs that expressed granulocyte chemotactic protein-2 (GCP-2) and platelet-derived growth factor-β (PDGF-β). The results revealed that three-dimensional (3D)-cultured ASCs overexpressing GCP-2 and PDGF-β (3D-A/GP) yielded a significant increase in proangiogenic gene expression, cell migration, and endothelial tube formation in vitro. Moreover, the Matrigel plug assay revealed that 3D-A/GP formed functional blood vessels, and 3D-A/GP injection in a hind limb ischemia (HLI) model revealed higher blood flow recovery, limb salvage, and capillary density and lower apoptosis in mice, compared to the controls. Notably, 3D-A/GP exhibited differentiation into endothelial-like cells and upregulated expression of angiogenic factors in ischemic limb tissue. Our results highlight the value of using a combination of genetic engineering and 3D culture systems to improve the therapeutic effect of ASCs in terms of angiogenesis-dependent tissue repair. The dual modulation of GCP-2 and PDGF-β, in combination with 3D culture, presents a new and synergistic opportunity to maximize the use of ASC-based therapies for ischemic diseases and other regenerative medicine applications. Full article

Human mesenchymal stem cells (hMSCs) and their secreted extracellular vesicles (EVs) are promising therapeutics to treat degenerative or inflammatory diseases such as ischemic stroke and Alzheimer’s disease (AD). hMSC-EVs have the coveted ability to contain therapeutically relevant biomaterials; however, EV biogenesis is sensitive to the culture microenvironment in vitro. Recently, the demand for hMSC-EVs has increased dramatically, highlighting the need for scalable bioreactors for large-scale biomanufacturing. In this study, adipose-derived hMSCs were seeded in 2D plates, an ultralow-attachment (ULA) plates as static aggregates, a novel vertical wheel bioreactor (VWBR) as aggregates, and a spinner flask bioreactor (SFB). EV secretion was quantified and compared using ExtraPEG-based ultracentrifugation and nanoparticle tracking analysis. Compared to the 2D group, significantly higher total EV production and cell productivity in the bioreactors were observed, as well as the upregulation of EV biogenesis genes. Furthermore, there was increased EV production in the VWBR compared to the SFB and the static ULA control. Functional assessments demonstrated that EVs, when delivered via culture medium or hydrogel-based systems, significantly attenuated oxidative stress elevation, suppressed proinflammatory cytokine secretion (e.g., TNF-α) and gene expression, and inhibited nuclear factor kappa-light-chain-enhancer of activated B-cell (NF-κB) activation and neurodegenerative markers across in vitro assays. These findings suggest EV-mediated mitigation of oxidative and inflammatory pathways, potentially through modulation of the NF-κB signaling cascade. This study shows the influence of bioreactor types and their microenvironments on EV secretion in hMSCs and their applications in hMSC-EV production and bioengineering. Full article

Chimeric Antigen Receptor (CAR) T cell therapy has achieved high response rates in patients with relapsed or refractory hematologic malignancies. However, comparable efficacy in solid tumors remains limited, partly due to poor CAR T cell persistence and immune-mediated rejection. A major contributor, which has hampered the clinical efficacy of CAR T cells in clinical practice, is the immunogenicity of the murine-derived single-chain variable fragments (scFvs) commonly used in CAR constructs. Cell and humoral immune responses to the murine parts of CARs have been implicated in CAR T cell rejection. Here, we describe the generation and in vitro characterization of humanized CAR T cells targeting prostate-specific membrane antigen (PSMA) on prostate cancer cells, based on two distinct murine scFvs (A5 and D7). Humanization improved the germinality index and successfully preserved CAR surface expression. Functional assays demonstrated that humanized PSMA-CAR T cells retained antigen-specific binding, activation and cytotoxicity, differentiation, exhaustion and cytokine secretion profiles comparable to their murine counterparts. These results support the feasibility of humanization as a strategy to reduce immunogenicity without compromising CAR T cell capabilities, providing a foundation for further in vivo validation in solid tumor settings. Full article

We report the synthesis and characterization of folic acid (FA)-conjugated human serum albumin nanoparticles, (HSA-FA):Ru NPs, as targeted carriers for rutin (Ru), a flavonoid with known anticancer activity. Nanoparticles were fabricated via a desolvation method, and their surface was functionalized with folic acid to promote selective uptake by cancer cells overexpressing folate receptors. Morphological and dimensional analyses performed by atomic force microscopy (AFM), scanning electron microscopy (SEM), and fluorescence microscopy confirmed that all nanoparticles were below 100 nm and exhibited good colloidal stability. Voltametric measurements confirmed the successful incorporation of both rutin and folic acid within the (HSA-FA):Ru nanoparticle formulation. Biological evaluation was conducted on healthy L929 fibroblasts and HT-29 colon adenocarcinoma cells. MTS colorimetric assays revealed that (HSA-FA):Ru NPs significantly reduced the viability of HT-29 cells, while maintaining higher compatibility with L929 cells. Fluorescence and electron microscopy further confirmed preferential nanoparticle uptake and surface accumulation in HT-29 cells, supporting the role of folic acid in enhancing targeted delivery. The study demonstrates that HSA-based nanoparticles functionalized with FA and loaded with Ru offer a biocompatible and efficient strategy for selective intracellular drug delivery in colorectal cancer. These findings support the use of albumin-based nanocarriers in the development of targeted therapeutic platforms for cancer treatment. Full article

We aimed to explore SARS-CoV-2 evolution during in vitro neutralisation using next generation sequencing, and to determine whether sera from individuals immunised with two doses of the Pfizer-BioNTech vaccine (BNT162b2) were as effective at neutralising the variant of concern (VOC) Delta (B.1.617.2) compared to the earlier lineages Beta (B.1.351) and wild-type (A.2.2) virus. Using a live-virus SARS-CoV-2 neutralisation assay in Vero E6 cells, we determined neutralising antibody titres (nAbT) against three SARS-CoV-2 strains (wild type, Beta, and Delta) in 14 participants (vaccine-naïve (n = 2) and post-second dose of BNT162b2 vaccination (n = 12)), median age 45 years [IQR 29–65]; the median time after the second dose was 21 days [IQR 19–28]. The determination of nAbT was based on cytopathic effect (CPE) and in-house quantitative reverse transcriptase real-time quantitative polymerase chain reaction (RT-qPCR) to confirm SARS-CoV-2 replication. A total of 110 representative samples including inoculum, neutralisation breakpoints at 72 h, and negative and positive controls underwent genome sequencing. By integrating live-virus neutralisation assays with deep sequencing, we characterised both functional antibody responses and accompanying viral genetic changes. There was a reduction in nAbT observed against the Delta and Beta VOC compared with wild type, 4.4-fold (p ≤ 0.0006) and 2.3-fold (p = 0.0140), respectively. Neutralising antibodies were not detected in one vaccinated immunosuppressed participant and the vaccine-naïve participants (n = 2). The highest nAbT against the SARS-CoV-2 variants investigated was obtained from a participant who was vaccinated following SARS-CoV-2 infection 12 months prior. Limited consensus level mutations occurred in the various SARS-CoV-2 lineage genomes during in vitro neutralisation; however, consistent minority allele frequency variants (MFV) were detected in the SARS-CoV-2 polypeptide, spike (S), and membrane protein. Findings from countries with high COVID-19 incidence may not be applicable to low-incidence settings such as Australia; as seen in our cohort, nAbT may be significantly higher in vaccine recipients previously infected with SARS-CoV-2. Monitoring viral evolution is critical to evaluate the impact of novel SARS-CoV-2 variants on vaccine effectiveness, as mutational profiles in the sub-consensus genome could indicate increases in transmissibility and virulence or suggest the development of antiviral resistance. Full article

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a multifunctional cytokine with therapeutic applications in oncology and neurodegenerative diseases. However, its clinical use is limited by the high cost of eukaryotic production systems. Here, we developed a cost-effective Escherichia coli-based platform for high-yield production of biologically active recombinant human GM-CSF (rhGM-CSF) using SUMO fusion technology. The engineered pET-SUMO-GM plasmid enabled expression of a 33 kDa fusion protein, accounting for 23–25% of total cellular protein, though it primarily accumulated in inclusion bodies. A multi-step purification strategy—including nickel affinity chromatography, Ulp protease cleavage, and hydrophobic chromatography—yielded >99.5% pure rhGM-CSF. In vitro functional assays demonstrated equivalent activity to the WHO international standard (ED50: 0.045 vs. 0.043 ng/mL in TF-1 cell proliferation). In vivo, the preparation significantly restored neutrophil counts (3.4-fold increase, p ≤ 0.05) in a murine cyclophosphamide-induced myelosuppression model. Our results establish a scalable, prokaryotic-based method to produce functional rhGM-CSF, overcoming solubility and folding challenges while maintaining therapeutic efficacy. This approach could facilitate broader clinical and research applications of GM-CSF, particularly in resource-limited settings. Full article

The WUSCHEL-related homeobox (WOX) gene family is integral to plant growth and development. Here, we identified 14 CcWOX genes from the Cinnamomum camphora genome and analyzed their phylogeny, conserved features, and expression patterns. Phylogenetic inference grouped CcWOX into the Ancient, Intermediate, and WUS clades, consistent with other plant lineages. Expression profiling across seven tissues/organs, together with qRT-PCR validation, revealed tissue-biased expression for several members (e.g., floral or root enrichment), suggesting gene-specific roles during development. Using AlphaFold3, we predicted monomeric structures for CcWOX proteins and an interface model compatible with an interaction between CcWOX3 and CcLBD33. Consistently, bimolecular fluorescence complementation (BiFC) in Nicotiana benthamiana detected nuclear YFP signals for cEYFP-CcWOX3 + nEYFP-CcLBD33 relative to appropriate negative controls, confirming a physical interaction in plant cells. While these findings support a putative WOX–LBD interaction module in C. camphora, the regulatory functions remain to be established. Overall, this work provides a framework for dissecting the CcWOX family in C. camphora and illustrates how AI-assisted structure prediction can be integrated with cell-based assays to accelerate hypothesis generation in plant developmental biology. Full article

Dental enamel discoloration, extrinsic staining, and periodontal biofilms remain persistent challenges in oral health. This study explores the in vitro, dual-functional potential of Magnolia figo flower extract (FMO), a sesquiterpene-rich botanical active phytochemical ingredient (API), for aesthetic and antimicrobial oral applications. FTIR identified characteristic terpenoid and long-chain fatty acid functional groups, including β-elemene, γ-elemene, and caryophyllene oxide. Whitening efficacy on coffee-stained bovine enamel was quantified using CIELAB colorimetry. The 0.5% FMO treatment achieved ΔE* = 8.49, which was within the clinical perceptibility threshold and the optimal biocompatibility balance. SEM confirmed no demineralization on the enamel surface after immersion in 3.0% FMO for 12 h. Antimicrobial assays demonstrated inhibition of Porphyromonas gingivalis, with MIC and MBC values of 0.25% and 0.5%, respectively. Biofilm formation was reduced by over 50% at a 0.148% concentration. Cytocompatibility assays using HGF-1 cells with various concentrations of FMO showed reduced cell viability at higher concentrations. When exposed for 5 min (simulating daily oral care) or 2 h, 0.5% FMO exhibited greater biocompatibility with L929 cells compared to toothpaste and peroxide-based agents. These findings suggest that FMO may serve as a natural candidate for dual-function oral care; however, further in vivo and clinical investigations are needed to validate its potential use within oral care treatments. Full article

Background: Alzheimer’s disease is a progressive neurodegenerative disorder characterized by cognitive decline and memory loss. Gamma (γ) oscillations are closely linked to learning and memory, and recent interest has grown around Gamma ENtrainment Using Sensory stimulation (GENUS) as a non-invasive neuromodulation strategy. However, the therapeutic impact of vibrotactile gamma stimulation under varying physical parameters such as acceleration remains underexplored. Methods: Differentiated SH-SY5Y cells were treated with amyloid-β (Aβ) and exposed to vibrotactile stimulation at 2.2 or 4.0 m/s². In vivo, male C57BL/6N mice (7 weeks old, 35 g) were administered scopolamine to induce neurotoxicity and randomly assigned to sham, scopolamine, donepezil, or vibrotactile stimulation groups (n = 10 each). Behavioral tests, biochemical assays, Western blotting, and immunohistochemistry were performed to evaluate cognitive function, oxidative stress, cholinergic activity, synaptic plasticity, and neuroinflammation. Results: In vitro, SH-SY5Y cells exposed to amyloid-beta (Aβ) were treated with vibrotactile stimulation, resulting in enhanced neuronal marker expression at 2.2 m/s². In vivo, mice receiving stimulation at 2.2 m/s² showed improved cognitive performance, reduced oxidative stress, restored cholinergic function, suppressed neuroinflammation, and enhanced synaptic plasticity. Mechanistically, these effects were associated with activation of the AKT/GSK3β/β-catenin pathway. Conclusions: Our findings demonstrate that vibrotactile gamma stimulation at 2.2 m/s² exerts greater therapeutic efficacy than higher acceleration, highlighting the importance of optimizing stimulation parameters. This work supports the potential of acceleration-tuned, non-invasive GENUS-based therapies as effective strategies for cognitive recovery in neurodegenerative conditions. Full article

Wound healing is a complex process, and propolis, a natural resin with antimicrobial, anti-inflammatory, and antioxidant properties, emerges as a promising candidate for its treatment. This systematic review analyzed 26 studies on propolis-functionalized biomaterials. Great diversity was observed in materials and incorporation techniques, including direct blending, surface coating, and nanoencapsulation. Mostly based on polysaccharides like chitosan, pectin, and bacterial cellulose, these formulations showed biocompatibility, biodegradability, and promoted inflammation reduction and tissue repair. In vitro assays confirmed high biocompatibility (>80% cell viability) and antimicrobial activity, while in vivo studies validated regenerative benefits. Despite their potential, marked heterogeneity in propolis composition (intrinsically variable due to its botanical and geographical origin, and processing methods), coupled with diverse concentrations used and the lack of standardization in assessment methods and results reporting, significantly limits cross-study comparability and reproducibility. Overcoming these challenges requires promoting greater standardization in extraction, characterization, and evaluation protocols, including chemical fingerprinting and more detailed and consistent reporting of findings. Despite these limitations, propolis–polysaccharide systems hold strong clinical potential, with further standardization and well-designed preclinical studies being essential for their effective translation, especially in chronic wound management. Full article

Background/Objectives: This study reports the synthesis of TiO₂ nanoparticles, their functionalization with folic acid (FA), and the subsequent loading with zinc phthalocyanine (ZnPc) to develop photosensitizers for photodynamic therapy (PDT) targeting glioma cells. Methods: TiO₂, TiO₂-FA, and TiO₂-FA-ZnPc nanoparticles were synthesized via a sol–gel process involving the hydrolysis and condensation of titanium (IV) isopropoxide. FA and ZnPc were incorporated in vitro during the synthesis. The resulting materials were characterized by transmission and scanning electron microscopy (TEM and SEM), X-ray diffraction (XRD), Raman and UV–Vis spectroscopy, thermogravimetric analysis (TGA), and nitrogen adsorption–desorption measurements. Reactive oxygen species (ROS) generation was evaluated in vitro using the 1,3-diphenylisobenzofuran (DPBF) probe. A 40 ppm solution of each TiO₂ system was irradiated with UV light, and the degradation of DPBF was monitored. Biological assays were conducted to assess the viability of human glioblastoma cells (LN18 and U251) incubated with the TiO₂-based materials, with and without UV exposure. Human fibroblast cells (BJ) were used to evaluate biocompatibility. Results: All TiO₂-based materials retained key characteristics, including high surface area (~600–700 m²/g), mesoporous structure (pore diameter ~4–5 nm), mixed anatase–amorphous morphology, and a bandgap of approximately 3.46 eV. The UV–Vis spectrum of TiO₂-FA-ZnPc displayed additional absorption bands in the visible region (600–700 nm), consistent with ZnPc incorporation. Upon UV irradiation, the DPBF absorbance at 410 nm decreased over time, indicating ROS generation and resulting in complete degradation within 10 min (TiO₂), 12 min (TiO₂-FA), and 14 min (TiO₂-FA-ZnPc). BJ cells exhibited good biocompatibility at all concentrations. LN18 and U251 cells showed no cytotoxicity below 100 μg/mL unless exposed to UV light. Conclusions: The synthesized TiO₂-based systems demonstrate good biocompatibility and significant phototoxicity under UV irradiation, highlighting their strong potential for application in photodynamic therapy. Full article

The detection of aliphatic and aromatic biogenic amines (BAs) is important in food spoilage, environmental monitoring, and disease diagnosis and treatment. Existing fluorescent probes predominantly detect aliphatic BAs with single signal variation and low sensitivity, impairing the adaptability of discriminative sensing platforms. Herein, we present a visual chemosensor (galactose-functionalized pyrrolopyrrole aza-BODIPY, PPAB-Gal) that simultaneously detects eight aliphatic and aromatic BAs in a real-time and intuitive way based on their unique electronic and structural features. Our findings reveal that the dual colorimetric and ratiometric emission changes are rapidly produced in presence of eight BAs through a noncovalent interaction (π–π stacking and hydrogen bond)-assisted chromophore reaction. Specifically, other lone-pair electrons containing compounds, such as secondary amines, tertiary amines, NH₃, and thiol, fail to exhibit these changes. As a result, superior sensing performances with distinctly dual signals (Δλ_ab = 130 nm, Δλ_em = 150 nm), a low LOD (~25 nM), and fast response time (<2 min) were obtained. Based on these advantages, a qualitative and smartphone-assisted sensing platform with a PPAB-Gal-loaded TLC plate is developed for visual detection of putrescine and cadaverine vapor. More importantly, we construct a connection between a standard quantitative index for the TVBN value and fluorescence signals to quantitatively determine the freshness of tuna and shrimp, and the method is facile and convenient for real-time and on-site detection in practical application. Furthermore, since the overexpressed spermine is an important biomarker of cancer diagnosis and treatment, PPAB-Gal NPs can be used to ratiometrically image spermine in living cells. This work provides a promising sensing method for BAs with a novel fluorescent material in food safety fields and biomedical assays. Full article

The genomes of viruses in the Allexivirus genus encode the p42 protein, which is considered the hallmark of the genus. The functions of p42 have not yet been studied experimentally and cannot be predicted based on sequence similarity, as p42-related proteins are not found among known cell or viral proteins. Here, p42 of Shallot virus X (ShVX), the type allexivirus, is demonstrated to be translated via a leaky scanning mechanism on a template comprising three “triple gene block” (TGB) transport genes and the p42 gene. Sequence analysis shows that this p42 expression mechanism is conserved in the vast majority of allexiviruses. p42 binds single-stranded RNA (ssRNA) but not double-stranded RNA (dsRNA) in vitro and localizes to the cytoplasm in association with microtubules and microtubule-bound bodies. In transient expression assays, p42 exhibits weak but detectable suppression of silencing induced by ssRNA but not by dsRNA. In addition, p42 suppresses silencing in the context of virus infection. Furthermore, p42 inhibits nonsense-mediated RNA decay (NMD) induced by a long 3′-terminal untranslated region of mRNA. Taken together, these findings provide initial evidence that the ShVX TGB/p42 gene module functions as a single genomic unit in terms of protein expression, that p42 acts as a suppressor of NMD and silencing, and that it may have multiple roles, while the precise biological significance of p42 in these roles remains to be experimentally confirmed. Full article

Background/Objectives: Controlled release systems, such as polymeric microparticles (MPs), have emerged as a promising solution to extend the bioavailability and reduce dosing frequency for biologic drugs; however, the formulation of these systems to encapsulate highly sensitive, hydrophilic biologic drugs within hydrophobic polymers remains a nontrivial task. Although scalable manufacturing and FDA approval of single emulsion processes encapsulating small molecules has been achieved, scaling more complex double emulsion processes to encapsulate hydrophilic biologics remains more challenging. Methods: Here, we demonstrate that two hydrophilic, low-molecular-weight, recombinant chemokines, CCL22 and CCL2, can be encapsulated in poly(lactic-co-glycolic acid) (PLGA) MPs using a single emulsion method where the proteins are dissolved in an organic solvent during formulation. Results: As expected, we observed some differences in release kinetics from single emulsion MPs compared to double emulsion MPs, which traditionally have been used to encapsulate proteins. Single emulsion MPs exhibited a substantially reduced initial burst. Importantly, protein released from single emulsion CCL22-MPs also retained biological activity, as determined by a cell-based functional assay. Decreasing particle size or changing the polymer end group from PLGA-COOH to PLGA-OH increased the initial burst from single emulsion MPs, demonstrating tunability of release kinetics for protein-loaded, single emulsion MPs. Finally, to improve scalability and enable more precise control over MP formulations, the single emulsion process was adapted to a microfluidic, continuous manufacturing system, and the resulting MPs were evaluated similarly. Conclusions: Altogether, this study demonstrates the feasibility of using a single emulsion encapsulation method for at least some protein biologics. Full article