Curcumin I-SMA nanomicelles as promising therapeutic tool to tackle bacterial infections

Curcumin-laden hydrogel coating medical device for periprosthetic joint infection prevention and control

The Periprosthetic Joint Infection (PJI) is one of the most important complications of the joint arthroplasty. This surgical procedure is rising worldwide and is further affecting the public health because of the widespread resistance to antibiotics. New therapeutic strategies and innovative antimicrobial biomaterials development are needed to eradicate pathogens without inducing resistance and accelerating recovery. In this direction, herein Curcumin I- (Cur-) loaded DAC® (Defensive Antibacterial Coating, a hydrogel based on hyaluronic acid conjugated to polylactic acid, hereafter named DAC) has been built on. To incorporate Cur in the DAC, thus obtaining Cur-DAC (Cur ≅ 0.93 mg/g), the generally recognized as safe (GRAS) propylene glycol (PG) was used as cosolvent. The drugs combinations of Cur (≅ 0.93 mg/g) and Vancomycin (Van) (at low dose that is ≅ 0.033 mg/g) within the hydrogel (Cur/Van-DAC) was alsoexperienced . Hydrogels were prepared and characterized by rheological investigations and their erosion together with the drug release profile over the time evaluated in physiological conditions. The nanohydrogels produced upon water dilution were characterized by AFM, DLS, and UV/Vis absorption and emission spectroscopies. Superior Cur stability over pH-, solvent- and photoinduced degradations resulted in the DAC matrix. The photoinduced antimicrobial activity of Cur-DAC against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecium was evaluated by spreading loaded DAC-based hydrogel onto titanium disk mimicking prosthesis, thus detecting a good reduction of bacterial load after 30 min of exposure to light and a subsequent decrease of cells number at 24 h in the absence of nutrients. The drug association in Cur/Van-DAC demonstrated the best activity against MRSA, even in the presence of nutrients, with respect to established DAC loaded with high amounts of Van (ranging from 18.7 mg/g to 45.8 mg/g) used during the surgery, due to the photoantibacterial activity of Cur, becoming promising to prevent and control joint infections.

Therapeutic effect of pH responsive Magainin II modified azithromycin plus curcumin micelles in different depth models of MRSA infection

Methicillin-resistant Staphylococcus aureus (MRSA) is a major pathogen responsible for serious infections in humans. The overuse of antibiotics has led to the evolution of resistance genes in bacteria. This study aimed to develop a pH-responsive micelle, loaded with therapy drugs and modified with antimicrobial peptides, to treat drug-resistant bacterial infections at varying depths. pH-responsive micelles containing azithromycin and curcumin, modified with Magainin II, were prepared using the thin-film dispersion method. The physicochemical properties of the micelles were characterized, and their targeting properties and therapeutic effects on bacterial infections were investigated both in vivo and in vitro across various depths. The micelles demonstrated excellent targeting of bacterial infection sites and released drugs in response to degradation at the disease site. The combination of curcumin and azithromycin effectively mitigated bacterial resistance through multiple mechanisms, enhancing the antibacterial effect while reducing the required azithromycin dosage and associated toxicity. In infection models of varying depths-skin, muscle, and lungs-the micelles exhibited strong antibacterial, anti-biofilm, and anti-inflammatory effects with low toxicity. These findings provide a promising strategy for addressing drug-resistant bacterial infections.

Nanostructured Strategies for Melanoma Treatment-Part I: Design and Optimization of Curcumin-Loaded Micelles for Enhanced Anticancer Activity

Background/Objectives: Melanoma is a pathology that affects a large part of the population, and the currently available therapies have many limitations, including the selective targeting of the site of action. This study explores the development of curcumin (CUR)-loaded nanostructured delivery systems for topical melanoma treatment, addressing CUR's limitations in bioavailability, solubility, and stability. Methods: Binary surfactant mixtures of Vitamin E-TPGS (TPGS) and Kolliphor ELP (ELP) were selected to form stable micelles for curcumin encapsulation. A Design of Experiments (DoE) approach was applied to optimize the surfactant ratios for enhanced drug solubilization and improved cytotoxic effects on melanoma cells. The final formulation was characterized using Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), and Nuclear Magnetic Resonance (NMR) spectroscopy to confirm its properties. Results: The final formulation, TPGS30ELP15, contained 30 mM TPGS and 15 mM ELP and led to formation of nanostructures of the expected size (hydrodinamic diameter, Dh: 13.11 ± 0.01 nm; polydispersivity index, PDI = 0.371 ± 0.05), able to solubilize 5.51 ± 1.09 mM CUR. The formulation was stable for a 120-day period stored at 4 °C and room temperature in the dark. Cytotoxicity testing in A375 melanoma cells demonstrated that curcumin-loaded micelles significantly reduced cell viability compared to free curcumin. Long-term exposure (24 h) revealed that free curcumin caused an 85% reduction in cell viability, while TPGS30ELP15 resulted in a 70% reduction. Additionally, free curcumin induced a 30% increase in cytoplasmic area, indicating necrosis, whereas TPGS30ELP15 decreased the cytoplasmic area by 20%, suggesting apoptosis. Conclusions: This study demonstrates that TPGS30ELP15 nanomicelles enhance curcumin's anticancer effects while promoting apoptosis and minimizing necrosis, which is associated with lower inflammation and tissue damage. These findings suggest that TPGS30ELP15 offers a more favorable therapeutic profile for melanoma treatment, paving the way for safer and more effective topical therapies.

Berberine-styrene-co-maleic acid nanomicelles: unlocking opportunities for the treatment and prevention of bacterial infections

The global spread of multi-drug-resistant (MDR) bacteria is rapidly increasing due to antibiotic overuse, posing a major public health threat and causing millions of deaths annually. The present study explored the potential of nanocarriers for delivering novel and alternative antibacterial agents using nanotechnology-based approaches to address the challenge of MDR bacteria. The purpose was to enhance the solubility, stability, and targeted delivery of berberine (BER) and its synthetic derivative NR16 using Styrene-co-Maleic Acid (SMA) nanoparticles. Characterization of the nanoparticles, including dynamic light scattering (DLS) analysis, TEM, and UV/Vis absorption spectroscopy, confirmed their suitability and high stability for passive drug delivery. Antibacterial and antifungal activities were evaluated against a panel of pathogens, revealing significant inhibitory effects on Gram-positive strains; particularly BER, SMA-BER, and NR16 were active against MRSA, MSSA, VR, and VS E. faecalis, and S. epidermidis. Additionally, SMA-BER and SMA-NR16 showed promising activity against biofilm formation of S. epidermidis; while the two free drugs contributed to S. epidermidis biofilm disruption activity. Hemolysis tests and in vitro studies on human embryonic kidney cells (HEK-293) confirmed the safety profiles of the nanoparticles and free drugs. Overall, this research highlighted the potential of nanotechnology in developing effective antibacterial agents with reduced toxicity, addressing the growing threat of MDR bacterial infections.

Advancements in wound healing: integrating biomolecules, drug delivery carriers, and targeted therapeutics for enhanced tissue repair

Wound healing, a critical biological process vital for tissue restoration, has spurred a global market exceeding $15 billion for wound care products and $12 billion for scar treatment. Chronic wounds lead to delayed or impaired wound healing. Natural bioactive compounds, prized for minimal side effects, stand out as promising candidates for effective wound healing. In response, researchers are turning to nanotechnology, employing the encapsulation of these agents into drug delivery carriers. Drug delivery system will play a crucial role in enabling targeted delivery of therapeutic agents to promote tissue regeneration and address underlying issues such as inflammation, infection, and impaired angiogenesis in chronic wound healing. Drug delivery carriers offer distinct advantages, exhibiting a substantial ratio of surface area to volume and altered physical and chemical properties. These carriers facilitate sustained and controlled release, proving particularly advantageous for the extended process of wound healing, that typically comprise a diverse range of components, integrating both natural and synthetic polymers. Additionally, they often incorporate bioactive molecules. Despite their properties, including poor solubility, rapid degradation, and limited bioavailability, various natural bioactive agents face challenges in clinical applications. With a global research, emphasis on harnessing nanomaterial for wound healing application, this research overview engages advancing drug delivery technologies to augment the effectiveness of tissue regeneration using bioactive molecules. Recent progress in drug delivery has poised to enhance the therapeutic efficacy of natural compounds in wound healing applications.