Search Results (351)

Oncomodulin (OCM) is the most abundant Ca²⁺ buffering protein found in mature outer hair cells (OHCs). Cadherin 23 (CDH23) is a crucial component of the tip-links in hair cell stereocilia. The absence or dysfunction of these two proteins contributes to the early onset of age-related hearing loss (AHL). In this study, we investigated the effects of the Cdh23^753G→A mutation on OHC function using new Ocm-knockout (KO) mouse models (Ocm^tm1a/tm1a) with or without the Cdh23^753G→A mutation. Despite having the same genetic background, Ocm-KO mice carrying the Cdh23^753G→A mutation displayed a notable decline in OHC function across all measured frequencies as early as three months of age. In contrast, Ocm-KO mice without the Cdh23^753G→A mutation did not exhibit comparable hearing loss until they reached twelve months of age. Additionally, we examined the role of OCM in preserving OHC function under ototoxic stress induced by HPβCD (2-hydroxypropyl-β-cyclodextrin). The distortion product otoacoustic emission data show that the administration of HPβCD resulted in a more pronounced decline in OHC function in Ocm-KO mice compared to wild-type (WT) mice. Time-lapse recording also shows that HPβCD treatment led to greater structural deterioration and more rapid rupture events in OHCs from Ocm-KO mice than in those from WT mice. These findings suggest that the Cdh23^753G→A mutation, rather than other potential strain-specific genetic factors associated with AHL, significantly exacerbates the early onset of AHL phenotypes in Ocm-KO mice. Furthermore, our data indicates that the OCM protein in OHCs enhances their ability to withstand ototoxic stimuli. Full article

Flunarizine is a calcium channel blocker widely used in neurological disorders; however, its low aqueous solubility may influence formulation stability and drug dispersion in polymer-based systems. The present study aimed to evaluate the compatibility of flunarizine with selected excipients and to investigate its incorporation into polymeric hydrogel matrices. Binary mixtures of flunarizine with excipients such as hydroxypropyl-β-cyclodextrin, polyethylene glycol (PEG 6000), Tween 20, gelatin, and citric acid were prepared and characterized using Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG/DTG), and high-performance liquid chromatography (HPLC). The FTIR spectra of the analyzed samples do not reveal the appearance of new absorption bands that may indicate chemical interactions; instead, minor spectral variations were observed due to weak intermolecular interactions within the polymer network. Thermal analysis revealed decomposition patterns consistent with those of the individual components, suggesting the absence of significant incompatibilities. A validated RP-HPLC method enabled sensitive and reliable quantification of flunarizine in the analyzed systems, with a limit of detection (LOD) of 0.05 µg/mL and a limit of quantitation (LOQ) of 0.16 µg/mL. Accuracy testing showed average recovery rates of 100% across 80–120% spiking levels. Overall, the results support the compatibility of flunarizine with the investigated excipients and the suitability of the studied hydrogels as potential drug delivery matrices. Full article

Background/Objectives: Inclusion complexes among drugs and cyclodextrin-modified polymers are a topic of recent interest in pharmaceutical research and industry as they might expand the solubility, bioavailability, and stability of the guest molecules. Polyurethanes derived from cyclodextrins show some biomedical applications. In this study, two cross-linked polyurethane networks based on hydroxypropyl-β-cyclodextrin (HPβCD) and polyethylene glycols (PEG 2000 or PEG 6000) were synthesized with NCO/OH molar ratio 4.3 and 6.3 by the typical two-step polymerization method. Methods: Inclusion complexes of clotrimazole (CLOT) with two HPβCD-modified polyurethane networks and their corresponding physical mixtures were prepared using kneading methods and physical mixing in a 1:6 weight ratio of CLOT:HPβCD. Results: Obtained prepolymers, previously end-capped with isocyanate groups forming urethane links with HPβCD, which were confirmed by FTIR analysis. TGA results indicate a slight increase in thermal stability of the prepared complexes. The characteristic endothermic peak of the CLOT at around 145.90 °C did not appear in the DSC curve of the drug-loaded inclusion complexes. The XRD patterns of physical mixtures showed specific peaks corresponding to pure clotrimazole. SEM micrographs confirmed an elliptical/spherical- and plate-shaped particles without phase segregation, indirectly confirming that CLOT is not separately present due to inclusion into HPβCD and entrapment into polyurethane networks. Novel complexes PUR2/HPβCD-CLOT-IC and PUR3/HPβCD-CLOT-IC were applied as drug carriers, and diffusion-controlled kinetics of CLOT release were best described using Higuchi model. Conclusions: The obtained in vitro results showed surprisingly slow/prolonged clotrimazole release from modified polyurethane networks due to the significant influence of NCO/OH molar ratio and the chosen polyol soft segments chain length with potential in vivo applications. 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

Isoflavones are plant-derived polyphenols with broad biological activity; however, their application in topical formulations is limited by poor aqueous solubility. The aim of this study was to enhance the aqueous solubility of formononetin using a solvent-free hot-melt extrusion (HME) approach and to enable its incorporation into a hydrogel formulation suitable for skin delivery. Amorphous formononetin-based systems were prepared by HME using polymeric carriers and hydroxypropyl-β-cyclodextrin, with and without prior inclusion complex formation. The resulting formulations were characterized using XRPD, DSC, and FT-IR/ATR to assess amorphization and intermolecular interactions. Aqueous solubility and skin permeability were evaluated using solubility testing, PAMPA, and Franz diffusion cells. The optimized amorphous system exhibited a substantial increase in apparent aqueous solubility compared to crystalline formononetin while maintaining comparable permeability. Cyclodextrin–formononetin interactions were effectively generated during the extrusion process, rendering pre-inclusion unnecessary. The selected system was successfully incorporated into a hydrogel matrix. This study demonstrates that solvent-free HME combined with cyclodextrins is an effective strategy for improving formononetin solubility and enabling its application in hydrogel-based topical delivery systems. Full article

Metabolic dysfunction-associated steatohepatitis (MASH) is a form of fatty liver disease characterized by fat accumulation, hepatic inflammation, and fibrosis. Lysophosphatidylethanolamine (LPE), a partially deacylated product of phosphatidylethanolamine, plays significant roles in anti-inflammatory responses and mitochondrial homeostasis. Although serum LPE levels are reduced in patients with MASH, the underlying mechanisms remain unclear. In this study, we investigated LPE metabolism using liquid chromatography–tandem mass spectrometry and protein expressions in MASH mice. Male C57BL/6J mice were fed a high-fat, high-cholesterol, and cholic acid diet, along with 2% hydroxypropyl-β-cyclodextrin in drinking water (HFCC/CDX) for three weeks to induce MASH. LPE was primarily distributed in the liver and kidneys, with lower levels in the white adipose tissue. HFCC/CDX mice exhibited accumulation of cholesterols and oxidized triglycerides, accompanied by inflammation and fibrosis in the liver. In the plasma and liver of HFCC/CDX mice, most LPE species were decreased and showed negative correlations with hepatic inflammation, with the exception of LPE 18:1. Mechanistically, enhanced degradation of LPE to glycerophosphorylethanolamine was associated with upregulation of Pnpla6/7 in the liver. These findings suggest that Pnpla6/7-driven LPE catabolism is contributing to LPE depletion. This study provides a new perspective to understand the association between disrupted phospholipid metabolism and MASH pathogenesis. Full article

Adipose tissue macrophages (ATMs) are key mediators of obesity-induced inflammation and insulin resistance. However, the contribution of lysosomal dysfunction to ATM inflammatory activation remains poorly defined. Here, we characterized lysosomal structural and functional alterations in ATMs during obesity and examined whether pharmacological restoration of lysosomal function using 2-hydroxypropyl-β-cyclodextrin (HPβCD) ameliorates metabolic inflammation. In diet-induced obese C57BL/6J male mice, adipose tissue exhibited increased lysosomal abundance, accompanied by reduced cathepsin L+V expression, modestly increased lysosomal acid lipase levels, and decreased expression of transcription factor EB (TFEB), a master regulator of lysosomal biogenesis. Despite expanded lysosomal content, ATMs displayed impaired lysosomal acidification, indicating functional lysosomal dysfunction. Intraperitoneal administration of HPβCD for two weeks significantly improved glucose tolerance and insulin sensitivity without affecting body weight. Flow cytometric analysis revealed reduced pro-inflammatory M1 ATMs and CD8⁺ T lymphocytes in visceral adipose tissue, whereas immune cell populations in subcutaneous adipose tissue, blood, and spleen remained unchanged. In vitro, HPβCD suppressed pro-inflammatory gene expression in both classically and metabolically activated macrophages and attenuated inflammatory responses induced by lysosomal stressors, including bafilomycin A1 and chloroquine, while restoring TFEB expression. Collectively, these findings demonstrate that obesity is associated with lysosomal dysfunction in ATMs and that restoration of lysosomal function alleviates adipose tissue inflammation and metabolic dysfunction, highlighting lysosomal regulation in ATMs as a potential therapeutic target for obesity-associated metabolic diseases. Full article

Propolis is a rich natural source of biologically active polyphenols; however, their therapeutic potential is often limited by poor oral bioaccessibility and bioavailability. This study reports the development and validation of a high-performance liquid chromatography–diode array detector (HPLC–DAD) method optimized for the quantification of major propolis polyphenols—caffeic acid (CA), pinocembrin (PC), chrysin (CR), caffeic acid phenethyl ester (CAPE), and galangin (GN) in 2-hydroxypropyl-β-cyclodextrin (HP-β-CD)-based complexes. A green complexation approach based on HP-β-CD and lyophilization was applied to continental propolis, yielding a water-soluble formulation suitable for oral administration. The isocratic HPLC–DAD method demonstrated linearity, sensitivity, and precision, suitable for reliable analysis of polyphneols in cyclodextrin-based matrices. Gastrointestinal behavior was evaluated using a simulated oral, gastric, and intestinal digestion model. PC and CAPE remained stable throughout digestion, whereas GN, CR, and CA showed higher sensitivity, with decreases of 43.1–71.6% compared to undigested samples. HP-β-CD complexation enhanced polyphenol solubility and improved gastrointestinal stability. Intestinal bioaccessibility, assessed by a centrifugation model, ranged from 77.2% (CR) to 124.9% (CA). However, the complexes did not permeate the artificial intestinal membrane, resulting in reduced dialyzable polyphenols, with CA being undetectable. These findings provide a validated analytical platform and mechanistic insight into the gastrointestinal behavior of cyclodextrin-complexed propolis polyphenols, supporting their application in oral functional formulations. Full article

Cyclodextrins (CyDs) are cyclic oligosaccharides that form inclusion complexes that allow organic compounds and other substances to be incorporated into their cavities. Hydroxypropyl-β-cyclodextrin (HP-β-CyD) is frequently used to improve the formulation properties of poorly water-soluble drugs because of its aqueous solubility and biocompatibility. Previous studies have demonstrated that the solubility and biocompatibility of poorly water-soluble anti-cancer agents can be improved by complexation with HP-β-CyD, which in some cases enhances their anticancer activity relative to the unmodified drugs. Advances in formulation strategies have enabled more efficient intracellular delivery, improved tissue and cell selectivity, and controlled release. HP-β-CyD has also been investigated as an active pharmaceutical ingredient, with demonstrated efficiency in treating leukemia and breast cancer. For example, folate-conjugated HP-β-CyD exhibits high selectivity for folate receptor-expressing cells and more potent anti-cancer activity than unmodified HP-β-CyD. Autophagy has been suggested to be involved in this mechanism. The continued development of drug-delivery systems that integrate advanced technologies and materials based on HP-β-CyD holds promise for further advances in cancer therapy. These findings indicate a paradigm shift in the role of HP-β-CyD from a formulation additive to an active pharmaceutical ingredient, suggesting broader applications for HP-β-CyD in anticancer treatments. Full article

The aim of this study was to prepare curcumin/2-hydroxypropyl-β-cyclodextrin (HPβCD) inclusion complex, evaluate the antioxidant and antimicrobial activities of curcumin and curcumin in inclusion complex, as well as to examine the effect of curcumin and curcumin inclusion complex on the textural properties of Carbopol^® gel mixture. Curcumin/2-hydroxypropyl-β-cyclodextrin inclusion complex was prepared using the co-precipitation method in a molar ratio of 1:1. The antioxidant activity of curcumin and curcumin in inclusion complex was determined using DPPH, ABTS, and FRAP methods. The micro-dilution method was used to examine in vitro the antimicrobial activity of curcumin and curcumin in inclusion complex. The textural, rheological, and morphological properties of the samples (Gel 1- Carbopol^® gel; Gel 2- Carbopol^® gel with dispersed curcumin inclusion complex; Gel 3- Carbopol^® gel with dispersed curcumin) were examined. The textural properties were evaluated using a texturometer CT3 Texture Analyzer by means of a Texture Profile Analysis (TPA) test. The results showed that curcumin in inclusion complex had higher antioxidant and antimicrobial activity. The SEM confirms the presence of curcumin and inclusion complex in Carbopol^® gel. The rheological analysis confirmed that the structural integrity of Carbopol^® gel was preserved. The highest swelling degree is achieved by Gel 3 formulation. The in vitro release of curcumin from Gel 2 and Gel 3 occurs at the rates of 0.414 µg/h·g_gel and 0.376 µg/h·g_gel, respectively. The textural analysis showed that adding curcumin or its inclusion complex did not significantly change the properties of Carbopol^® gel, indicating potential for topical use. Full article

The contamination of water bodies by polycyclic aromatic hydrocarbons (PAHs) poses a significant concern for the ecological systems, along with public health. Magnetic adsorption stands out as a green and practical solution for treating polluted water. To make the process more efficient and economical, it is important to create materials that not only absorb contaminants effectively but also allow for easy recovery and reuse. This study proposes a simple yet effective method for coating Fe₃O₄ nanoparticles with hydroxypropyl-β-cyclodextrin polymer (HP-β-CDCP). The physicochemical properties of the synthesized sorbent were characterized using a transmission electron microscope (TEM), Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and Vibrating Sample Magnetometer (VSM) analysis. The adsorption performance of HP-β-CDCP/Fe₃O₄ nanoparticles was well-described by the pseudo-second-order kinetic model, thermodynamic analysis, and the Freundlich isotherm model, indicating multiple interaction mechanisms with PAHs, such as π–π interactions, hydrogen bonding, and van der Waals forces. Using HP-β-CDCP/Fe₃O₄ nanoparticles as the adsorbent, the purification rates for the fifteen representative PAHs were achieved within the range of 33.9–93.1%, compared to 15.3–64.8% of the unmodified Fe₃O₄ nanoparticles. The adsorption of all studied PAHs onto HP-β-CDCP/Fe₃O₄ nanocomposites was governed by pH, time, and temperature. Equilibrium in the uptake mechanism was obtained within 15 min, with the largest adsorption capacities for PAHs in competitive adsorption mode being 6.46–19.0 mg·g⁻¹ at 20 °C, pH 7.0. This study points to the practical value of incorporating cyclodextrins into tailored polymer frameworks for improving the removal of PAHs from polluted water. Full article

Spray freeze-drying (SFD) is a novel technique for formulating dry powders, particularly for pulmonary drug delivery via dry powder inhalers (DPIs). Despite their low density and excellent aerodynamic properties, such powders are affected by high cohesiveness due to their surface properties. Sugars such as mannitol (MAN), trehalose, raffinose, and sucrose are commonly used in SFD. MAN is widely employed due to its high MAN—ice eutectic temperature—at which MAN and water (ice) form a stable eutectic mixture—and its crystallinity. However, crystallinity can impact the microparticles’ (MPs) cohesiveness, since MAN exhibits distinct polymorphs (α, β, δ) with peculiar properties. This study provides valuable insights for the development of DPI formulations by ensuring precise control over MAN polymorphism, ultimately enhancing formulation stability and performance. We introduced, for the first time, an intermediate freezing (IF) step within the SFD process to modulate MAN polymorphism, demonstrating its synergy with optimised storage temperature conditions. Furthermore, polyvinylpyrrolidone, 2-hydroxypropyl beta cyclodextrin, dextran, and polysorbate 80 were employed as polymorphism-controlling agents for MAN, contributing to the development of stable formulations with reduced particle cohesion and improved storage stability at room temperature. For the first time, this study shows that MAN polymorphism in SFD can be controlled to drive dry powder inhaler performance. Full article

Background/Objectives: Hesperetin (HSP) is a bioactive flavonoid known for its strong antioxidant and anti-inflammatory properties. However, its low water solubility (1.36 ± 0.30 μg/mL) and poor oral bioavailability (~20%) greatly hinder its potential in nutraceutical applications. Methods: Using the solvent dispersion method, nanoparticles composed of HSP, hydroxypropyl-β-cyclodextrin (HPBCD), and polyvinylpyrrolidone K30 (PVPK30) were prepared and collectively termed HHPNP. Characterization involved particle size measurement, FTIR, XRD, SEM, and TEM. Antioxidant activity was evaluated using DPPH and ABTS⁺ radical scavenging assays. In vitro dissolution testing was performed at pH 1.2 and pH 6.8 to compare HHPNP with physical mixtures, and release behavior was assessed using both gelatin (non-vegetarian) and HPMC (vegetarian) capsules. Results: The optimal formulation (1:15:12) produced uniformly distributed spherical nanoparticles with a mean size of 14.87 ± 0.49 nm and achieved an 827-fold increase in water solubility compared with raw HSP. FTIR analysis indicated hydrogen bond formation, and XRD confirmed a complete transition from a crystalline to an amorphous state. In aqueous environments, HHPNP demonstrated markedly improved antioxidant activity, with DPPH and ABTS⁺ radical scavenging comparable to HSP solutions prepared in methanol. In vitro dissolution testing revealed rapid release at both pH 1.2 (>65% in 10 min) and at pH 6.8 (70% in 5 min). In contrast, physical mixtures only released 10–30% over two hours. T50% values at pH 1.2 were 17.8 min (gelatin) and 16.8 min (HPMC). At pH 6.8, T50% values were 17.6 min (gelatin) and 7.5 min (HPMC). Both capsule types matched the HHPNP in release at 120 min, and these comparable profiles indicate the formulation’s stability and adaptability across capsule variants. Conclusions: This nanoparticle-based delivery system, leveraging molecular inclusion and amorphization, significantly enhanced the solubility, bioactivity, and release efficiency of HSP, offering a potent platform for oral flavonoid-based dietary supplements. Full article

This study presents a novel hydrogel formulation combining mupirocin, a broad-spectrum antibiotic, with keratinocyte growth factor (KGF) to enhance wound healing through antibacterial action and tissue regeneration. Mupirocin was encapsulated in hydroxypropyl β-cyclodextrin (HP-β-CD) and stabilized with poly(amidoamine) dendrimers (PAMAM). Molecular docking studies assessed mupirocin’s binding to PAMAM and its interaction with isoleucyl-tRNA synthetase. Physicochemical properties—including zeta potential, particle size, and surface tension—were characterized, and drug release kinetics were evaluated using Franz diffusion cells. In vitro assays on human dermal fibroblasts (HS27) included proliferation, scratch wound healing, and flow cytometry to assess cellular behavior. Antibacterial efficacy was determined via the Kirby–Bauer disk diffusion method. Results showed strong binding of mupirocin to its target enzyme, enhanced by KGF. The hydrogel exhibited favorable properties: surface tension of 24.7 dyne/cm, zeta potential of −24.79 mV, and particle size of ~119 nm, indicating high stability. Franz diffusion revealed sustained drug release compared to commercial mupirocin. Cellular assays demonstrated significant fibroblast migration and proliferation, with flow cytometry confirming increased wound healing markers. The formulation showed potent antimicrobial activity, including against Methicillin-resistant Staphylococcus aureus (MRSA), highlighting its promise for infected wound treatment and advanced clinical wound care. Full article

In this study, we review the use of cyclodextrin-based formulations to develop oral tablets of cladribine by enhancing its bioavailability and to improve the solubility and stability of retrometabolic chemical delivery systems (CDSs) in general and estredox, a brain-targeting estradiol-CDS, in particular. Cyclodextrins (CDs), cyclic oligosaccharides that can form host–guest inclusion complexes with a variety of molecules, are widely utilized in pharmaceuticals to increase drug solubility, stability, bioavailability, etc. The stability of the complex depends on how well the guest fits within the cavity of the CD host; a model connecting this to the size of the guest molecules is briefly discussed. Modified CDs, and particularly 2-hydroxypropyl-β-cyclodextrin (HPβCD), provided dramatically increased water solubility and oxidative stability for estredox (estradiol-CDS, E₂-CDS), making its clinical development possible and highlighting the potential of our brain-targeted CDS approach for CNS-targeted delivery with minimal peripheral exposure. A unique HPβCD-based formulation also provided an innovative solution for the development of orally administrable cladribine. The corresponding complex dual CD-complex formed by an amorphous admixture of inclusion- and non-inclusion cladribine–HPβCD complexes led to the development of tablets that provide adequate oral bioavailability for cladribine, as demonstrated in both preclinical and clinical studies. Cladribine–HPβCD tablets (Mavenclad) offer a convenient, effective, and well-tolerated oral therapy for multiple sclerosis, achieving worldwide approval and significant clinical success. Overall, the developments summarized here underscore the importance of tailored cyclodextrin-based approaches for overcoming barriers in drug formulation for compounds with challenging physicochemical properties, and demonstrate the versatility and clinical impact of CD inclusion complexes in modern pharmaceutical development. Full article