Curcumin-Loaded Micelles Dispersed in Ureasil-Polyether Materials for a Novel Sustained-Release Formulation

The Development and Pre-Clinical Anti-Inflammatory Efficacy of a New Transdermal Ureasil-Polyether Hybrid Matrix Loaded with Flavonoid-Rich Annona muricata Leaf Extract

This study aimed to develop a novel ureasil-polyether transdermal hybrid matrix (U-PEO) loaded with Annona muricata concentrated extract (AMCE), which exhibits potent anti-inflammatory activity. The extract was obtained by maceration, a method that allowed for the extraction of a high concentration of flavonoids (39.27 mg/g of extract). In vivo tests demonstrated that 10 mg/kg of AMCE inhibited inflammation for 6 h. The physicochemical characterization of U-PEO with AMCE was conducted via a thermogravimetric analysis (TGA), while its surface was recorded using atomic force microscopy (AFM). The in vitro macroscopic swelling and release tests demonstrated the hydrophilic profile of the material and the percentage of AMCE released. The TGA results demonstrated that the system exhibited physical compatibility due to the thermal stability of U-PEO. Additionally, the AFM analysis revealed a rough and porous surface, with a particular emphasis on the system with AMCE. The release resulted in the liberation of 23.72% of AMCE within 24 h. Finally, the preclinical tests demonstrated that U-PEO with AMCE was also capable of effectively inhibiting inflammation for 6 h, a duration comparable to that of a commercial formulation. The results permit the advancement of the study towards the development of a transdermal system, thereby rendering its application in clinical studies feasible.

Cellulose Acetate Microparticles Synthesized from Agave sisalana Perrine for Controlled Release of Simvastatin

Simvastatin (SIM) is widely prescribed to treat hyperlipidemia, despite its limitations, such as a short half-life and low oral bioavailability. To overcome these drawbacks, the development of a controlled-release formulation is desirable. This study aims to develop a microparticulate system based on cellulose acetate (ACT) obtained from Agave sisalana Perrine to promote a controlled SIM release. SIM-loaded microparticles (SMP) were prepared using the solvent emulsification-evaporation method. Several parameters were evaluated, including particle size, surface charge, morphology, encapsulation efficiency, thermochemical characteristics, crystallinity, and in vitro release profile. ACT exhibited favorable flow properties after acetylation, with a degree of substitution values superior to 2.5, as confirmed by both the chemical route and H-NMR, indicating the formation of cellulose triacetate. The obtained SMP were spherical with an average size ranging from 1842 to 1857 nm, a zeta potential of -4.45 mV, and a high SIM incorporation efficiency (98%). Thermal and XRD analyses revealed that SIM was homogeneously dispersed into the polymeric matrix in its amorphous state. In vitro studies using dialysis bags revealed that the controlled SIM release from microparticles was higher under simulated intestinal conditions and followed the Higuchi kinetic model. Our results suggest that ACT-based microparticles are a promising system for SIM delivery, which can improve its bioavailability, and result in better patient compliance.

Licochalcone A Protects Vaginal Epithelial Cells Against Candida albicans Infection Via the TLR4/NF-κB Signaling Pathway

Vulvovaginal candidiasis (VVC) is a prevalent condition affecting a significant portion of women worldwide. Licochalcone A (LA), a natural compound with diverse biological activities, holds promise as a protective agent against Candida albicans (C. albicans) infection. This study aims to investigate the potential of LA to safeguard vaginal epithelial cells (VECs) from C. albicans infection and elucidate the underlying molecular mechanisms. To simulate VVC in vitro, VK2-E6E7 cells were infected with C. albicans. Candida albicans biofilm formation, C. albicans adhesion to VK2-E6E7 cells, and C. albicans-induced cell damage and inflammatory responses were assessed by XTT reduction assay, fluorescence assay, LDH assay, and ELISA. CCK-8 assay was performed to evaluate the cytotoxic effects of LA on VK2-E6E7 cells. Western blotting assay was performed to detect protein expression. LA dose-dependently hindered C. albicans biofilm formation and adhesion to VK2-E6E7 cells. Furthermore, LA mitigated cell damage, inhibited the Bax/Bcl-2 ratio, and attenuated the secretion of pro-inflammatory cytokines in C. albicans-induced VK2-E6E7 cells. The investigation into LA's impact on the Toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) pathway revealed that LA downregulated TLR4 expression and inhibited NF-κB activation in C. albicans-infected VK2-E6E7 cells. Furthermore, TLR4 overexpression partially abated LA-mediated protection, further highlighting the role of the TLR4/NF-κB pathway. LA holds the potential to safeguard VECs against C. albicans infection, potentially offering therapeutic avenues for VVC management.

Delivery of paclitaxel by carboxymethyl chitosan-functionalized dendritic fibrous nano-silica: Fabrication, characterization, controlled release performance and pharmacokinetics

In this study, carboxymethyl chitosan (CMCS) with excellent biocompatibility was used as the "gatekeeper" to design and fabricate a pH-responsive drug delivery system (CMCS-DFNS) as paclitaxel carriers. Characterization results showed that CMCS-DFNS was successfully prepared and the nanocarriers displayed excellent drug loading efficiency of 19.8 %, and the results of the adsorption mechanism revealed that the adsorption of PTX was consistent with the Freundlich isotherm and pseudo-second-order kinetic model. Furthermore, the pH-responsive controlled release behavior at different pH (pH = 7.4, 6.5, and 5.0) was evaluated, and the results demonstrated that the cumulative release at pH 5.0 was 58.8 %, which was 2.7 times higher than that at pH 7.4, suggesting that the carrier exhibited a good pH sensitivity. The results of in vitro cellular experiments further indicated that CMCS-DFNS significantly improved the drug uptake efficiency in breast cancer MCF-7 cells. Importantly, the results of in vivo and cellular pharmacokinetic revealed that CMCS-DFNS can improve the circulation time and enhance the relative bioavailability of paclitaxel. Therefore, the fabricated pH-responsive drug delivery system has potential applications in the delivery of anti-tumor drugs, and provides a new delivery pathway for other compounds with low bioavailability.

Potential of Nanomedicines as an Alternative for the Treatment of Colorectal Cancer - A Review

Colorectal cancer is the third most common cancer and the second in cases of cancer-related death. Polytherapy generates many adverse effects, leading the patient to give up. Nanotechnology has been studied in recent years to circumvent limitations. Groups composed of polymeric, lipid, and inorganic nanoparticles are the most purpose. Thus, the objective of this work is to bring information on how nanosystems can improve the chemotherapeutic treatment for colorectal cancer. Therefore, a search in journals such as "LILACS", "SciELO" and "PubMed/Medline" was performed, resulting in 25,000 articles found when applied the search engines "nanoparticle," "colorectal cancer," "malignant neoplasms," and "chemotherapy." After inclusion and exclusion factors, 24 articles remained, which were used as the basis for this integrative review. The results reveal that, regardless of the choice of matrix, nanoparticles showed an increase in bioavailability of the active, increasing the half-life by up to 13 times, modified release, as well as a significant reduction in tumor size, with cell viability up to 20% lower than the free drug tested, in different colorectal cancer cell lines, such as HCT-116, HT-29, and CaCo-2. However, more in vivo and clinical studies need to be performed, regardless of the formulation of its matrix, aiming at a higher rate of safety for patients and stability of the formulations, as well as knowledge of detailed indices of its pharmacokinetics and pharmacodynamics, seeking to avoid further damage to the recipient organism.

Radiolabelled folate micellar carriers as proposed diagnostic aid for CNS tumors by nasal route

Glioma refers to the most atypical variant of the malignant central nervous system tumors posturing massive challenge to the research fraternity owing to the flimsy improvement in the patient survival rate over the past years. The aim of the proposed work was developing a diagnostic aid for brain tumors, which could be administered via the non-invasive intranasal route. Since overexpression of folate receptors in the central nervous system tumors is 500 times more than the normal healthy cells, we aimed at fabricating a radiolabeled folate encapsulated micellar delivery system to be given via the nasal route. Folate conjugated bifunctional chelating agent was synthesized, radiolabeled with 99mTc, and encapsulated in a micellar carrier. The fabricated micelles were further evaluated for in vivo nasal toxicity in rats and the same were found safe for intranasal administration. The fabricated micelles owing to their nano size, mucoadhesive nature, and enhanced permeation were observed to have a higher uptake into the brain (around 16% in 4 h) than as compared to the radiolabeled conjugated folate solution when studied for in vivo biodistribution in mice. Single-photon emission computerized tomography imaging performed in higher animals upon intranasal administration of the micellar formulation revealed enhanced uptake of the micelles into the animal brain. It is believed that the aforementioned formulation can be of a great diagnostic value in the detection of not only brain tumors but also other folate expressing cancers such as cervical, breast, and lungs as the system is fast, non-toxic, accurate, non-invasive, and simple.

Curcumin-Loaded Oil-Free Self-Assembled Micelles Inhibit the Influenza A Virus Activity and the Solidification of Curcumin-Loaded Micelles for Pharmaceutical Applications

Curcumin, a well-known natural lipophilic phenolic compound, plays a vital role in inhibiting the influenza infection. Currently, many kinds of formulations for the enhancement of a water dispersion of curcumin have been developed; however, the anti-influenza abilities of formulated curcumin have been much less investigated. In this study, the optimized self-assembled micelles of RH 40/Tween 80 loaded with curcumin (Cur-M) in an oil-free-based system were spherical with a hydrodynamic size at 13.55 nm ± 0.208 and polydispersity at 0.144 characterized by atomic force microscopy and dynamic light scattering, respectively. Additionally, Cur-M significantly increased the bioactivity/stability of curcumin and effectively inhibited the influenza A virus infection and its replication after viral entry, indicating the alteration of the inhibition mechanisms of curcumin against virus infection via RH 40/Tween 80 micelle formulation. Furthermore, a solid formulation (Cur-SM) of Cur-M was successfully developed by a one-pot physical adsorption method using a small amount of adsorbent and ~50% of curcumin/Cur-M that could be burst released from Cur-SM in 1 h, facilitating the fast-releasing applications. Ultimately, all of the results show that Cur-SM acts as a good nano-formulation of curcumin with improved solubility/dispersity in aqueous solutions and demonstrate new anti-influenza mechanisms of curcumin for pharmaceutical development.

Enhancement of Release and Solubility of Curcumin from Electrospun PEO-EC-PVP Tripolymer-Based Nanofibers: A Study on the Effect of Hydrogenated Castor Oil

This study reveals the state-of-the-art fabrication of a tripolymer-based electrospun nanofiber (NF) system to enhance the release, solubility, and transdermal penetration of curcumin (Cur) with the aid of in situ release of infused castor oil (Co). In this regard, Cur-loaded Co-infused polyethylene oxide (PEO), ethyl cellulose (EC), and polyvinyl pyrrolidone (PVP) tripolymer-based NF systems were developed to produce a hybridized transdermal skin patch. Weight percentages of 1-4% Cur and 3-10% of Co were blended with PEO-EC-PEO and PEO-EC-PVP polymer systems. The prepared NFs were characterized by SEM, TEM, FT-IR analysis, PXRD, differential scanning calorimetry (DSC), and XPS. Dialysis membranes and vertical Franz diffusion cells were used to study the in vitro drug release and transdermal penetration, respectively. The results indicated that maintaining a Cur concentration of 1-3 wt % with 3 wt % Co in both PEO-EC-Co-Cur@PEO and PEO-EC-Co-Cur@PVP gave rise to nanofibers with lowered diameters (144.83 ± 48.05-209.26 ± 41.80 nm and 190.20 ± 59.42-404.59 ± 45.31 nm). Lowered crystallinity observed from the PXRD patterns and the disappearance of exothermic peaks corresponding to the melting point of Cur suggested the formation of an amorphous NF structure. Furthermore, the XPS data revealed that the Cur loading will possibly take place at the inner interface of PEO-EC-Co-PEO and PEO-EC-Co-PVP NFs rather than on the surface. The beneficiary role of Co on the release and dermal penetration of Cur was further confirmed from the respective release data which indicated that PEO-EC-Co-Cur@PEO would lead to a rapid release (4-5 h), while PEO-EC-Co-Cur@PVP would lead to a sustained release over a period of 24 h in the presence of Co. Transdermal penetration of the released Cur was further evidenced with the development of color in the receiver compartment of the diffusion cell. DPPH results further corroborated that a sustained antioxidant activity is observed in the released Cur where the free-radical scavenging activity is intact even after subjecting to an electrospinning process and under extreme freeze-thaw conditions.

Photodynamic potential of hexadecafluoro zinc phthalocyanine in nanostructured lipid carriers: physicochemical characterization, drug delivery and antimicrobial effect against Candida albicans

This study aims to develop and characterize NCL loaded with ZnF16Pc (Pc) for application in antimicrobial photodynamic therapy. For the development of the NLC, the fusion-emulsification technique followed by sonication was applied. NLC and Pc-NLC were characterized in terms of mean diameter (Dm.n), polydispersity index (PdI), zeta potential (ZP), encapsulation efficiency (%EE), transmission electron microscopy (TEM), differential scanning (DSC), photobleaching and singlet oxygen generation in cellular systems (SOSG), and in vitro release assays performed by the beaker method, using dialysis membranes. Cell viability was performed by colony forming units (CFU/mL). The mean size of NLC and Pc-NLC was 158 nm ± 1.49 to 161.80 nm and showed PdI < 0.3 and ZP between -17.8 and -19.9, and stable during storage time (90 days). The TEM presented spherical particles, the Pc-NLC promoted the encapsulation of 75.57% ± 0.58. DSC analysis confirmed that there was no incompatibility between Pc and NLC. The analysis of the photodegradation profile proved to be photostable after encapsulation and this corroborates the data obtained by SOSG. In vitro release showed controlled and prolonged release. PDT Pc-NLC exhibited greater antifungal effect against C. albicans (3 log10 reduction) than Pc-NLC without light (1 log10 reduction). NLC can be an alternative to the application of Pc and improve the effect during PDT treatment.

Dexamethasone-Loaded Ureasil Hydrophobic Membrane for Bone Guided Regeneration

Physical barrier membranes have been used to release active substances to treat critical bone defects; however, hydrophilic membranes do not present a prolonged release capacity. In this sense, hydrophobic membranes have been tested. Thus, this study aimed to develop hydrophobic membranes based on mixtures of ureasil-polyether-type materials containing incorporated dexamethasone (DMA) for the application in guided bone regeneration. The physicochemical characterization and biological assays were carried out using small-angle X-ray scattering (SAXS), an in vitro DMA release study, atomic force microscopy (AFM), a hemolysis test, and in vivo bone formation. The swelling degree, SAXS, and release results revealed that the u-PPO400/2000 membrane in the proportion of 70:30 showed swelling (4.69% ± 0.22) similar to the proportions 90:10 and 80:20, and lower than the proportion 60:40 (6.38% ± 0.49); however, an equal release percentage after 134 h was observed between the proportions 70:30 and 60:40. All u-PPO materials presented hemocompatibility (hemolysis ≤2.8%). AFM results showed that the treatments with or without DMA did not present significant differences, revealing a flat/smooth surface, with no pores and/or crystalline precipitates. Finally, in vivo results revealed that for both the commercial hydrophilic membrane and u-PPO400/2000 (70:30) after 60 days, the bone formation volume was 21%. In conclusion, hybrid membranes present unique characteristics for treating critical bone defects, considering the delayed and prolonged release results associated with the physical barrier capacity.