RESUMO
A key strategy in enhancing the efficacy of collagen-based hydrogels involves incorporating polysaccharides, which have shown great promise for wound healing. In this study, semi-interpenetrating polymeric network (semi-IPN) hydrogels comprised of collagen (Col) with the macrocyclic oligosaccharide ß-cyclodextrin (ß-CD) (20-80 wt.%) were synthesised. Fourier-transform infrared (FTIR) spectroscopy confirmed the successful fabrication of these Col/ß-CD hydrogels, evidenced by the presence of characteristic absorption bands, including the urea bond band at â¼1740 cm-1, related with collagen crosslinking. Higher ß-CD content was associated with increased crosslinking, higher swelling, and faster gelation. The ß-CD content directly influenced the morphology and semi-crystallinity. All Col/ß-CD hydrogels displayed superabsorbent properties, enhanced thermal stability, and exhibited slow degradation rates. Mechanical properties were significantly improved with contents higher than ß-CD 40 wt.%. These hydrogels inhibited the growth of Escherichia coli bacteria and facilitated the controlled release of agents, such as malachite green, methylene blue, and ketorolac. The chemical composition of the Col/ß-CD hydrogels did not induce cytotoxic effects on monocytes and fibroblast cells. Instead, they actively promoted cellular metabolic activity, encouraging cell growth and proliferation. Moreover, cell signalling modulation was observed, leading to changes in the expression of TNF-α and IL-10 cytokines. In summary, the results of this research indicate that these novel hydrogels possess multifunctional characteristics, including biocompatibility, super-swelling capacity, good thermal, hydrolytic, and enzymatic degradation resistance, antibacterial activity, inflammation modulation, and the ability to be used for controlled delivery of therapeutic agents, indicating high potential for application in advanced wound dressings.
Assuntos
Antibacterianos , Bandagens , Colágeno , Preparações de Ação Retardada , Liberação Controlada de Fármacos , Escherichia coli , Hidrogéis , beta-Ciclodextrinas , Hidrogéis/química , Hidrogéis/farmacologia , beta-Ciclodextrinas/química , Antibacterianos/farmacologia , Antibacterianos/química , Preparações de Ação Retardada/química , Colágeno/química , Escherichia coli/efeitos dos fármacos , Humanos , Cicatrização/efeitos dos fármacos , Inflamação/tratamento farmacológico , Animais , CamundongosRESUMO
Cutaneous leishmaniasis (CL) is a neglected tropical disease. The treatment is restricted to drugs, such as meglumine antimoniate and amphotericin B, that exhibit toxic effects, high cost, long-term treatment, and limited efficacy. The development of new alternative therapies, including the identification of effective drugs for the topical and oral treatment of CL, is of great interest. In this sense, a combination of topical photodynamic therapy (PDT) with chloroaluminum phthalocyanine liposomes (Lip-ClAlPc) and the oral administration of a self-emulsifying drug delivery system containing fexinidazole (SEDDS-FEX) emerges as a new strategy. The aim of the present study was to prepare, characterize, and evaluate the efficacy of combined therapy with Lip-ClAlPc and SEDDS-FEX in the experimental treatment of Leishmania (Leishmania) major. Lip-ClAlPc and SEDDS-FEX were prepared, and the antileishmanial efficacy study was conducted with the following groups: 1. Lip-ClAlPc (0.05 mL); 2. SEDDS-FEX (50 mg/kg/day); 3. Lip-ClAlPc (0.05 mL)+SEDDS-FEX (50 mg/kg/day) combination; 4. FEX suspension (50 mg/kg/day); and 5. control (untreated). BALB/c mice received 10 sessions of topical Lip-ClAlPc on alternate days and 20 consecutive days of SEDDS-FEX or FEX oral suspension. Therapeutical efficacy was evaluated via the parasite burden (limiting-dilution assay), lesion size (mm), healing of the lesion, and histological analyses. Lip-ClAlPc and SEDDS-FEX presented physicochemical characteristics that are compatible with the administration routes used in the treatments. Lip-ClAlPc+SEDDS-FEX led to a significant reduction in the parasitic burden in the lesion and spleen when compared to the control group (p < 0.05) and the complete healing of the lesion in 43% of animals. The Lip-ClAlPc+SEDDS-FEX combination may be promising for the treatment of CL caused by L. major.
RESUMO
The aims of this work were to evaluate the antibacterial and antiproliferative potential in vitro of the metal complex with 4-aminobenzoic acid (Ag-pABA) and a drug delivery system based on bacterial cellulose (BC-Ag-pABA). The Ag-pABA complex was characterized by elemental analysis, high resolution mass spectrometry and single-crystal X-ray diffraction techniques, which indicated a 1:2 metal/pABA composition plus a nitrate ion coordinated to silver by the oxygen atom, with the coordination formula [Ag (C7H7NO2)2(NO3)]. The coordination of pABA to the silver ion occurred by the nitrogen atom. The in vitro antibacterial activity of the complex evaluated by minimum inhibitory concentration assays demonstrated the effective growth inhibitory activity against Gram-positive, Gram-negative biofilm producers and acid-alcohol resistant Bacillus. The antiproliferative activities against a panel of eight tumor cells demonstrated the activity of the complex with a significant selectivity index (SI). The DNA interaction capacity and the Ames Test indicated the absence of mutagenicity. The BC-Ag-pABA composite showed an effective capacity of sustained release of Ag-pABA. The observed results validate further studies on its mechanisms of action and the conditions that mediate the in vivo biological effects using animal models to confirm its safety and effectiveness for treatment of skin and soft tissues infected by bacterial pathogens, urinary tract infections and cancer.
Assuntos
Ácido 4-Aminobenzoico/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Celulose/química , Prata/farmacologia , Antibacterianos/química , Preparações de Ação Retardada , Testes de Sensibilidade Microbiana , Prata/químicaRESUMO
Devices such as contact lenses and collagen shields have been used to improve the antibiotic bioavailability of eye drops formulations in the treatment of ulcerative keratitis. Nevertheless, these devices are not sustained drug delivery systems, and a combination with eye drops is necessary. In animal patients, it requires constant supervision by trained personnel to avoid device loss, which increases the cost of treatment. In this study, PVA/anionic collagen membranes containing ciprofloxacin or tobramycin were prepared using two different methodologies, and the release, physical and antimicrobial properties were evaluated. The membrane containing ciprofloxacin was selected as a sustained drug delivery system with antibacterial activity against Staphylococcus aureus and Escherichia coli during 48 h. Despite to be opaque, due to its heterogeneous morphology, this membrane had the adequate mechanical strength, water content, hydrophilicity, water vapor permeability, and surface pH to interact with cornea without causing discomfort. In the surface of this membrane it was observed dispersed collagen fibrils which could serve as a substrate for corneal proteinases, contributing to the reduction in stromal damage and enhancing the epithelium regeneration. These results encourage the idea these membranes are new cost-effective and safe alternatives to treat corneal ulcers in animal patients.
Assuntos
Antibacterianos/química , Ciprofloxacina/química , Colágeno/química , Úlcera da Córnea/tratamento farmacológico , Portadores de Fármacos/química , Soluções Oftálmicas/química , Álcool de Polivinil/química , Antibacterianos/farmacologia , Materiais Biocompatíveis/química , Ciprofloxacina/farmacologia , Lentes de Contato , Córnea/efeitos dos fármacos , Composição de Medicamentos , Escherichia coli/efeitos dos fármacos , Humanos , Fenômenos Mecânicos , Soluções Oftálmicas/farmacologia , Permeabilidade , Staphylococcus aureus/efeitos dos fármacos , Propriedades de Superfície , Tobramicina/farmacologia , Água , MolhabilidadeRESUMO
Resumen Objetivo: Evaluar la permeabilidad, retención y biodistribución de los LUD-PcAlCl in vivo. Metodología: Los transferosomas fueron obtenidos mediante rehidratación de película lipídica. Ratas Wistar fueron tratadas tópica e intraperitonealmente con los transferosomas por 5 días. La penetración ex vivo fue determinada mediante el ensayo en celdas de Franz y la retención por el método de la cinta adhesiva. Cinco y treinta días postratamiento se obtuvo la piel y órganos para determinar la retención del compuesto y realizar estudios histopatológicos. La PcAlCl fue extraída con solventes y cuantificada por fluorometría. Los resultados se expresaron en nM PcAlCl/mg órgano. Resultados: La PcAlCl no penetró la piel en los ensayos ex vivo, reteniéndose principalmente en el estrato córneo. Cinco días post-tratamiento tópico la PcAlCl fue retenida en estrato córneo (41,76±0,02), mostrando concentraciones mínimas en bazo (0,09±0,02), epidermis-dermis (0,06±0,17), hígado (0,03±0,02) y pulmón (0,02±0,01 nM). Por vía intraperitoneal se encontró PcAlCl en bazo (0,58±0,4), cerebro (0,07±0,07), corazón (0,07±0,12), pulmón (0,012±0,01) y piel (0,021±0,02 nM). Treinta días postratamiento no se encontró PcAlCl en ningún órgano. Los estudios histopatológicos fueron negativos. Conclusión: La PcAlCl contenida en transferosomas fue retenida principalmente en estrato córneo, mostrando bajas concentraciones en la dermis, sitio donde se aloja el parásito. Se sugiere modificar los componentes vesiculares del sistema para aumentar la permeación del compuesto.
Abstract Objective: To assess the UDL-ClAlPc permeability, retention and biodistribution in vivo. Methods: Transferosomas were obtained by lipid film re-hydration method. Wistar rats were treated topically and intraperitoneally with UDL-ClAlPc for 5 days. Skin and organs were collected five and thirty days after-treatment to determine ClAlPc retention and histopatho-logical studies. The ClAlPc was extracted with solvents and quantified by fluorometry. The results were expressed in nM PcAlCl/mg organ. The permeation was tested ex vivo using Franz-diffusion cells and the retention in stratum corneum and epidermis-dermis by tape stripping. Results: In the ex vivo experiments ClAlPc-UDL was not able to penetrate rat skin and was retained mainly in the stratum corneum. In rat, five days after topical treatment ClAlPc was retained mainly in the stratum corneum (41.76±0.02) with minimum concentrations in spleen (0.09±0.02), epidermis-dermis (0.06±0.17), liver (0.03±0.02) and lung (0.02±0.01 nM). After intra peritoneal treatment, ClAlPc was found in spleen (0.58±0.4), brain (0.07±0.07), heart (0.07±0.12), lung (0.01±0.012) and skin (0.021±0.02 nM). Thirty days post-treatment ClAlPc was not found in any organ. Histopathological studies were negative. Conclusion: The ClAlPc contained in transferosomes was retained mainly in the stratum corneum. Low concentration was detected in dermis a place where the parasite survives. This vehicle needs to be improved to increase skin penetration.