Search Results (250)

Sarcopenia is characterized by progressive loss of skeletal muscle mass and function and is a major contributor to frailty, disability, and mortality in older adults. Store-operated calcium entry (SOCE) is a crucial regulator of skeletal muscle calcium homeostasis, and impaired SOCE has been linked to age-related muscle weakness. Here, we identify the synaptophysin family member synaptophysin-like protein 2, also known as mitsugumin 29 (MG29; encoded by the human gene SYPL2 and the mouse ortholog Mg29), as a key organizer of triad membrane cholesterol and lipid signaling required for normal SOCE during aging. Using Mg29^−/− mice as a model of accelerated sarcopenia, together with RNA interference against Mg29 in adult muscle and primary myotubes, we quantified changes in muscle morphology, contractile function, SOCE activity, and targeted lipidomic profiles. Reduced MG29 expression led to decreased muscle fiber cross-sectional area, reduced specific force, blunted SOCE, and marked alterations in membrane cholesterol content and fatty acid-derived lipid mediators. Cholesterol depletion by methyl-β-cyclodextrin in wild-type myotubes produced SOCE defects similar to those observed in aged wild-type and young Mg29⁻/⁻ muscles, indicating that MG29-dependent maintenance of membrane cholesterol is required for normal SOCE. Acute Mg29 knockdown also altered myogenic differentiation, the expression of calcium-handling and stress-response genes, and the release and consumption of specific polyunsaturated fatty acid-derived lipid mediators. Together, these findings identify MG29 as a critical regulator of SOCE and lipid signaling in skeletal muscle and suggest that its age-related decline contributes to sarcopenia by disrupting triad membrane organization and excitation–contraction coupling. Full article

This study explores the formation of inclusion complexes between a newly synthesized N-(2-(butylamino)-2-oxoethyl)-2-(3-cyano-4-isobutoxyphenyl)-4-methylthiazole-5-carboxamide with β-cyclodextrin using density functional theory with dispersion correction (DFT-D3) at the B3LYP-GD3/3-21G, 6-31G(d), 6-31G’(d), and 6-311G(d) levels. Two orientations are considered: in Orientation A, the 3-cyano-4-isobutoxyphenyl moiety interacts with the primary hydroxyl rim of β-cyclodextrin, while in Orientation B, the amide side chain faces the wider rim. Complexation energies and thermodynamic parameters are calculated to determine stability. Electronic properties, including HOMO-LUMO energies, and global reactivity descriptors, such as electronegativity (χ), chemical potential (μ), hardness (η), and electrophilicity index (ω), are evaluated. Non-covalent interaction (NCI) analysis is also performed to visualize interaction sites. The results reveal the significant influence of orientation on the host–guest complex stability and electronic properties, providing valuable insights into cyclodextrin-based encapsulation systems. The study provides a computational blueprint for engineering cyclodextrin-based bio-functional systems, where orientation-controlled inclusion governs stability, reactivity, and performance. This can significantly impact the development of smart drug delivery systems, biosensors, and multifunctional biomaterials in modern bioengineering. Full article

Drug delivery systems have long faced a fundamental challenge: achieving high drug-loading efficiency, precise control over release, and in vivo safety simultaneously is a difficult task. Cellulose and its derivatives are abundant and renewable, exhibiting good biocompatibility, which makes them promising candidates for drug delivery materials. Representative derivatives, such as carboxymethyl cellulose, hydroxypropyl methyl cellulose, and ethyl cellulose, as well as nanocellulose, including cellulose nanocrystals, cellulose nanofibrils, and bacterial nanocellulose, have enabled the development of diverse carrier formats, including hydrogels, aerogels, films, and particulate systems. Recent advances include pH-responsive bacterial nanocellulose/carboxymethyl cellulose hydrogels for oral ibuprofen delivery, carboxylated nanocellulose/polyethylene glycol/β-cyclodextrin composite aerogels for gastric-selective release of imatinib, and hydroxypropyl methyl cellulose-based microneedle patches for transdermal co-delivery of sumatriptan succinate and naproxen sodium. These examples highlight how cellulose-based systems can be engineered for site-selective delivery, sustained release, and multi-stimuli responsiveness. In this review, we summarize the structural features of cellulose derivatives and nanocellulose, discuss the design principles and release mechanisms of representative delivery platforms, and outline current challenges in manufacturability, safety evaluation, and clinical translation. Full article

In this study, we evaluated various density functional theory (DFT) methods to obtain thermodynamic parameters, such as enthalpy and Gibbs free energy, and compared them with experimental values obtained from conductometric analysis. As a model system, we chose the heptakis(2,6-di-O-methyl)-β-cyclodextrin (DIMEB) complex with the recently synthesized fluorinated compound, butane-1,4-diyl bis(2,2,2-trifluoroethane-1-sulfonate) (BFS). The analysis was carried out in the temperature range of 293.15–313.15 K. A conformational search was performed to identify the most stable complexes. The final stage of optimization was conducted at the ωB97X-D4/6-31G(d,p) level of theory in the presence of water, modeled using the conductor-like polarizable continuum model (CPCM). The thermodynamic analysis indicates that almost all theoretical methods overestimate the enthalpy and Gibbs free energy. This also applies to Minnesota functionals, which are commonly recommended for thermochemistry studies. The best agreement with experimental results was obtained for the composite methods r²SCAN-3c and PBEh-3c, with the coefficient of determination (R² = 0.9972) indicating excellent correlation between r²SCAN-3c and experiment. Full article

Intranasal administration is a promising drug delivery route enabling precise and rapid central nervous system targeting. In our previous work, twelve hybrid colloidal dispersions were developed, consisting of synthetic poly(ethylene-oxide)-b-poly(ε-caprolactone) (PEO-b-PCL) block copolymers with an increasing proportion of the hydrophobic PCL segment, Tween 80 (Tw80) and β-cyclodextrin derivatives (βCD), either methyl-β-CD (MβCD) or hydroxy-propyl-β-CD (HPβCD) for IN delivery of ropinirole hydrochloride (RH). Colloidal dispersions were prepared at different weight ratios (system/RH equal to 10:1 and 10:5), characterized and evaluated in vitro. The aim of this study is to evaluate the ex vivo permeation through rabbit nasal mucosa and determine the pharmacokinetic parameters of RH, when administered intranasally as a colloidal dispersion, compared with oral and intranasal RH solutions in C57BL/6J mice. Ex vivo permeation studies showed that all formulations significantly enhanced RH permeation compared to the pure RH solution (0.5 mg/mL, pH 5.6). Among them, F4 [(PEO-b-PCL₁/Tw80/HPβCD)/RH 10:5] was selected for further investigation. Pharmacokinetic analysis showed that F4 significantly enhanced both systemic and brain exposure of RH, achieving higher serum AUC and C_max values, despite a 3-fold lower administered dose compared to the oral dose. It showed high systemic (F_rel(Serum) = 1815%) and brain (F_rel(Brain) = 363%) relative bioavailability compared with oral administration, underscoring its potential as an intranasal delivery system for efficient CNS targeting. Full article

Background/Objectives: Essential oils (EOs) have multi-target antifungal activity, but their translation is limited by volatility and poor aqueous dispersibility. Randomly methylated β-cyclodextrin (RAMEB) inclusion may enhance effective exposure and thereby alter susceptibility, stress responses, and biofilm outcomes in a species-dependent manner. This study quantified species-specific planktonic and biofilm susceptibility to four EOs and their RAMEB complexes across clinically relevant Candida species. Methods: Lavender (L), lemon balm (B), peppermint (P), and thyme (T) oils and their RAMEB complexes (RL, RB, RP, and RT) were tested against C. albicans and non-albicans Candida. Susceptibility thresholds were used to derive phase plasticity metrics. Functional inhibition was assessed via planktonic metabolism/viability and established biofilm metabolism/viability/biomass. Mechanistic signatures were captured by ROS/RNS measurements and a qPCR analysis of antioxidant genes (CAT1, GPX1, and SOD1) was performed. Mixed-effects models and multivariate/unsupervised and interpretable classification approaches (k-means, PCA, and CRT) were used to integrate endpoints and stratify response phenotypes. Results: Susceptibility thresholds were strongly species-structured (lowest MIC₉₀/EC₁₀ for C. albicans; higher thresholds and broader sublethal windows in non-albicans species). RAMEB complexation produced formulation-dependent shifts in efficacy, with RT emerging as the most consistent broad-spectrum inhibitory condition across compartments. Biofilm biomass was comparatively insensitive even when viability was suppressed, indicating a decoupling of structural biomass from biocidal activity. Mechanistic signatures were broadly conserved across species and linked to antioxidant-program engagement, with CAT1-related rules contributing to responder/tolerant classification. Conclusions: Integrating MIC/EC plasticity with functional and mechanistic markers supports the rational selection of EO formulations; RAMEB complexation, particularly RT, prioritizes candidates for further pharmaceutical optimization while highlighting species-specific vulnerabilities. Full article

This review critically examines how cyclodextrins modulate regulated cell death pathways and the implications for immunometabolism and therapeutic translation. Increasing evidence, however, indicates that cyclodextrins exert intrinsic biological activity by modulating cellular lipid homeostasis, membrane organization, and intracellular trafficking. In recent years, these properties have positioned cyclodextrins as unexpected regulators of regulated cell death (RCD) pathways, with broad implications for immunometabolism and therapeutic innovation. This review provides a comprehensive overview of the mechanisms by which native and chemically modified cyclodextrins influence major forms of regulated cell death, including apoptosis, autophagy-dependent cell death, pyroptosis, ferroptosis, and necroptosis. Particular attention is given to cholesterol sequestration, lipid raft disruption, lysosomal cholesterol mobilization, and transcriptional reprogramming via pathways such as TFEB (transcription factor EB) and AMPK (AMP-activated protein kinase), which collectively shape cell fate decisions. We further examine how cyclodextrin-mediated modulation of RCD intersects with immune metabolism, especially macrophage polarization and inflammasome activity, thereby influencing inflammatory responses and disease progression. Translational implications are discussed across diverse pathological contexts, including cancer, cardiovascular diseases, neurodegenerative disorders, inflammatory and autoimmune conditions, infectious diseases, and lysosomal storage disorders. Finally, emerging cyclodextrin-based delivery platforms, ranging from inclusion complexes to nanoparticles and polymeric systems, are evaluated with respect to their ability to achieve targeted modulation of cell death while minimizing off-target toxicity. Importantly, we critically discuss dose-dependent cytotoxicity, sterol depletion–related adverse effects, and formulation-dependent variability, which currently limit the clinical translation of cyclodextrin-mediated cell death modulation. By integrating mechanistic insights with pharmaceutical formulation strategies, this review delineates key challenges and opportunities for the rational design of cyclodextrin-based therapeutics. Overall, this review highlights cyclodextrins as bioactive modulators rather than inert carriers, underscoring their potential to inspire novel pharmacological strategies that integrate drug delivery, immunometabolism, and regulated cell death. Full article

Angiogenesis depends on Ca²⁺-mediated endothelial cell migration. The increase in intracellular Ca²⁺ concentration ([Ca²⁺]_i) is coordinated by caveolae and the Cx43 hemichannel opening. However, the functional coupling of voltage-dependent Na⁺ channels (Na_v) with Na⁺-Ca²⁺ exchanger reverse mode (NCXrm) activation may contribute to the response, which was evaluated using the wound-healing assay in primary cultures of rat mesenteric endothelial cells. Changes in [Ca²⁺]_i, the hemichannel opening and the association of Na_v channels with caveolin-1, a caveolae structural protein, were analyzed. Both endothelial cell migration and the associated Ca²⁺ signaling were inhibited by tetrodotoxin (TTX), a Na_v channel blocker, lamotrigine, a preferential Na_v1.2 inhibitor, or 4,9-anhydro-TTX, a specific Na_v1.6 blocker. A similar result was found by disrupting caveolae organization with methyl-β-cyclodextrin or blocking NCXrm with SEA0400. TTX and SEA0400 also prevented Cx43 hemichannel opening, and tubular-like structure formation depended on Na_v channels. An analysis using a proximity ligation assay showed that endothelial cell migration was paralleled by the progressive association of caveolin-1 with Na_v1.2, but not Na_v1.6, channels. These results suggest that the functional coupling of Na_v1.2 and Na_v1.6 channels with the activation of NCXrm and Cx43 hemichannels mediates the Ca²⁺ signaling associated with endothelial cell migration and angiogenesis, which provides new targets to modulate angiogenesis in physiological or pathological conditions. Full article

Membrane proteins remain the most challenging targets for structural characterization, yet their elucidation provides valuable insights into protein function, disease mechanisms, and drug specificity. Structural biology platforms have advanced rapidly in recent years, notably through the development and implementation of nanodiscs—discoidal lipid–protein complexes that encapsulate and solubilize membrane proteins within a controlled, native-like environment. While nanodiscs have become powerful tools for studying membrane proteins, faithfully reconstituting the compositional asymmetry intrinsic to nearly all biological membranes has not yet been achieved. Proper membrane leaflet lipid distribution is critical for accurate protein folding, stability, and insertion. Here, we share a protocol for reconstituting tailored compositional asymmetry within nanodiscs through membrane extraction from giant unilamellar vesicles (GUVs) treated with a leaflet-specific methyl-β-cyclodextrin (mβCD) lipid exchange. Nanodisc asymmetry is verified through a geometric approach: biotin-DPPE-preloaded mβCD engages in lipid exchange with the outer leaflet of POPC GUVs solubilized by the lipid-free membrane scaffold protein (MSP) Δ49ApoA-I to form nanodisc structures. Once isolated, nanodiscs are introduced to the biotin-binding bacterial protein streptavidin. High-speed atomic force microscopy imaging depicts nanodisc–dimer complexes, indicating that biotin-DPPE was successfully reconstituted into a single leaflet of the nanodiscs. This finding outlines the first step toward engineering tailored nanodisc asymmetry and mimicking the native environment of integral proteins—a potentially powerful tool for accurately reconstituting and structurally analyzing integral membrane proteins whose functions are modulated by lipid asymmetry. Full article

Severe acute respiratory syndrome coronavirus (SARS-CoV) assembles and buds from the Golgi apparatus or the ER membrane, but the specific membrane microdomains utilized during this process remain underexplored. Here, we show that co-expression of the SARS-CoV structural proteins S, M, and N in HEK-293T cells is sufficient to generate genome-free SARS-CoV-like virus-like particles (VLPs), which preferentially bud from glycolipid-enriched membrane lipid raft microdomains. Immunofluorescence microscopy using raft-selective dyes (DiIC16) and spike-specific antibodies revealed strong co-localization of VLPs with lipid rafts. Detergent-resistant membrane analysis and sucrose gradient centrifugation further confirmed the presence of S protein in buoyant, raft-associated fractions alongside the raft marker CD44. Importantly, pharmacological disruption of rafts with methyl-β-cyclodextrin reduced VLP budding and S protein partitioning into raft domains, underscoring the requirement for intact lipid rafts in assembly. Additionally, our data support lipid raft-associated proteins’ (e.g., FNRA, VIM, CD59, RHOA) roles in modulating cellular responses conducive to viral replication and assembly. These findings highlight lipid rafts as crucial platforms for SARS-CoV morphogenesis and suggest new avenues for vaccine and antiviral development using VLPs and raft-targeting therapeutics. Full article

In this study, for the first time, the genes encoding the mammalian steroidogenesis system—cytochrome P450scc (CYP11A1), and its native redox partners adrenodoxin and adrenodoxin reductase—were successfully expressed in the methylobacterium Methylorubrum extorquens. The advantage of using methylobacteria as an expression chassis is that they grow on inexpensive mineral media, use methanol as a carbon and energy source, and do not possess their own sterol catabolism systems. Using recombinant methylobacteria, the valuable steroid pregnenolone was obtained as a sole metabolite from cholesterol. The effect of media composition, bioconversion conditions such as methanol and N-sources content, modes of substrate addition, detergents, methyl-β-cyclodextrin, biomass, and aeration on pregnenolone accumulation was investigated. Under optimized conditions, its yield exceeded 100 mg/L. The results demonstrate a proof of concept relating to the use of bacteria lacking their own steroid degradation systems as microbial chassis for heterologous steroidogenesis systems, including mammalian cytochrome CYP11A1. Full article

Background: Anemoside B4 (AB4), the major bioactive saponin from Pulsatilla chinensis, exhibits anti-inflammatory, anti-tumor, anti-apoptotic, and analgesic properties. However, its clinical translation for ulcerative colitis (UC) is constrained by poor epithelial permeability and low oral bioavailability. Objective: This study’s objective was to engineer and optimize thermosensitive rectal in situ gels (ISGs) of AB4, incorporating suitable absorption enhancers to improve mucosal permeation, bioavailability, and therapeutic efficacy against UC. Methods: Screening of effective permeation enhancers was conducted using Caco-2 cell monolayers and Franz diffusion cells. Critical formulation variables such as poloxamer 407 (P407), poloxamer 188 (P188), and hydroxypropyl methyl cellulose (HPMC) were optimized, employing single-factor experiments coupled with the Box–Behnken design response surface methodology (BBD-RSM). Comprehensive characterization encompassed in vitro release kinetics, in vivo pharmacokinetics, rectal tissue tolerability, rectal retention time, and pharmacodynamic efficacy in a UC model. Results: We used 2.5% hydroxypropyl-β-cyclodextrin (HP-β-CD) and 1.0% sodium caprate (SC) as the appropriate absorption enhancers, and the amounts of P407, P188, and HPMC were 17.41%, 4.07%, and 0.44%, respectively, to yield the corresponding in situ gels HP-β-CD-AB4-ISG and SC-AB4-ISG. The gel characterization, such as gelation temperature, gelation time, pH, gelation strength, etc., was in accordance with requirements. The ISGs did not stimulate or damage rectal tissue and remained in the rectum for a prolonged period. More importantly, an improvement in bioavailability and alleviation of UC were noted. Conclusion: Absorption enhancer-assisted, poloxamer-based thermosensitive rectal ISGs provide a safe, convenient, and effective platform for targeted delivery of AB4 to the colorectum. This strategy addresses key limitations of oral dosing and warrants further clinical development for UC and related colorectal inflammatory diseases. Full article

Apixaban (APX) is a direct oral anticoagulant with low aqueous solubility and limited bioavailability. This study aimed to improve APX solubility by forming spray-dried inclusion complexes (ICs) with β-cyclodextrin (β-CD) derivatives. ICs were prepared using hydroxypropyl-β-CD (HP-β-CD), sulfobutylether-β-CD (SBE-β-CD), randomly methylated-β-CD (RM-β-CD), and heptakis(2,6-di-O-methyl)-β-CD (DM-β-CD). Complex formation (1:1 stoichiometry) was confirmed by phase solubility studies and Job’s plots. The ICs were characterized by SEM, PXRD, DSC, and FTIR, and their saturated solubility was evaluated. Molecular docking assessed host–guest interactions. Among the tested carriers, DM-β-CD exhibited the highest stability constant (K_C = 371.92 M⁻¹) and produced amorphous ICs. DM-ICs achieved the greatest solubility enhancement at all pH conditions, with a maximum solubility of 1968.7 μg/mL at pH 1.2 and ~78.7-fold increase in water compared with pure APX. Docking results supported stable inclusion with the lowest binding free energy (−8.01 kcal/mol). These findings indicate that DM-β-CD-based ICs effectively enhance APX dissolution and show potential as solubilizing carriers for oral dosage forms. Full article

Cyclodextrins in metal oxide nanoparticles (NPs) serve as stabilizing, dispersing, and functionalizing agents that enhance antimicrobial performance through better nanoparticle stability, synergistic action, and potential controlled release mechanisms, making them ideal for advanced biomedical and environmental antimicrobial applications. In this study, NPs of vanadium pentoxide (V₂O₅) were obtained by the precipitation method, and, following a supramolecular assembly, were synthesized using the impregnation method via addition of β-cyclodextrin (BCD) and its derivatives, such as hydroxypropyl-β-cyclodextrin (HCD) and methyl-β-cyclodextrin (MCD). The formation of the V₂O₅:CDs was driven by non-covalent host–guest interactions, leading to a stable supramolecular structure with enhanced physicochemical properties. Morphological analysis using scanning electron microscopy (SEM) revealed uniformly distributed V₂O₅ NPs within the CD matrix. Structural characterization was further supported by proton nuclear magnetic resonance (NMR) spectroscopy, which confirmed the inclusion interactions between V₂O₅ and CDs. The synthesized NPs demonstrated significant antimicrobial activity against Gram-positive and fungal strains, indicating a synergistic enhancement in bioactivity due to the supramolecular architecture. This work highlights the potential of CD-assisted V₂O₅ NPs as promising antimicrobial agents for biomedical and environmental applications. Full article