Annexin A12-26 hydrogel improves healing properties in an experimental skin lesion after induction of type 1 diabetes.

Diabetes mellitus (DM) is characterized by metabolic alterations that involve defects in the secretion and/or action of insulin, being responsible for several complications, such as impaired healing. Studies from our research group have shown that annexin A1 protein (AnxA1) is involved in the regulation of inflammation and cell proliferation. In light of these findings, we have developed a new technology and evaluated its effect on a wound healing in vivo model using type 1 diabetes (T1DM)-induced mice. We formulated a hydrogel containing AnxA12-26 using defined parameters such as organoleptic characteristics, pH, UV-vis spectroscopy and cytotoxicity assay. UV-vis spectroscopy confirmed the presence of the associated AnxA12-26 peptide in the three-dimensional hydrogel matrix, while the in vitro cytotoxicity assay showed excellent biocompatibility. Mice showed increased blood glucose levels, confirming the efficacy of streptozotocin (STZ) to induce T1DM. Treatment with AnxA12-26 hydrogel showed to improve diabetic wound healing, defined as complete re-epithelialization and tissue remodeling, with reduction of inflammatory infiltrate in diabetic animals. We envisage that the AnxA12-26 hydrogel, with its innovative composition and formulation be efficient on improving diabetic healing and contributing on the expansion of the therapeutic arsenal to treat diabetic wounds, at a viable cost.

Advanced methylene blue - nanoemulsions for in vitro photodynamic therapy on oral and cervical human carcinoma.

Photodynamic therapy (PDT) is a therapeutic modality with high contributions in the treatment of cancer. This approach is based on photophysical principles, which presents as a less invasive strategy than conventional therapies. Combined with nanotechnology, the therapy becomes more efficient because nanoparticles (NPs) have advantageous characteristics such as biocompatibility, controlled, and targeted release, promoting solubility and decreasing the toxicity and side effects involved. In this work were developed nanoemulsions containing the methylene blue photosensitizer (MB) (MB/NE) and in the empty form (unloaded/NE). Subsequently, the mentioned nanomaterials were characterized by the measurement of dynamic light scattering (DLS). The MB/NE and unloaded/NE showed appropriate physical and chemical characteristics, with particle size ≤ 200 nm, polydispersity index close to 0.3, and zeta potential exhibiting negative charge, showing stable values during the analysis. The incorporation of the MB did not cause changes in the photophysical profile of the photosensitizer. The quantification performed showed an incorporation rate of 81.9%. Viability studies showed an absence of cytotoxicity for MB/NE in the concentrations of 10-75 µmol·L-1, free MB at the concentration of 75 µmol·L-1, and unloaded NE 47.5% (v/v), presenting viability close to 90%, respectively. PDT in vitro protocols applied to OSCC and HeLa cells showed a decrease in cell viability through only one irradiation, evidencing the photodynamic activity of the formulation when applied to cancer cells. The results obtained were superior to those found in the literature where they use free MB, showing that the association between nanotechnology and PDT optimizes the proposed protocol. From the results obtained, it is possible to indicate that the NE have high stability, with satisfactory physical-chemical parameters, in addition to not presenting cytotoxicity in the tested concentrations, showing their in vitro biocompatibility, in addition to presenting satisfactory effects when combined MB/NE with PDT, showing the potential of MB/NE as a very promising nanostructured photosensitizer for the treatment of some types of cancer.

Copolymer-nanocapsules of zinc phenyl-thio-phthalocyanine and amphotericin-B in association with antimicrobial photodynamic therapy (A-PDT) applications against Candida albicans yeasts.

Antimicrobial Photodynamic Therapy (A-PDT) is a modern and non-invasive therapeutic modality. Nanostructures like the polymeric nanocapsules (NC) has proved to be a system that has enormous potential to improve current antimicrobial therapeutic practice. NC of Zinc phenyl-thio-phthalocyanine and Amphotericin B association (NC/ZnS4Pc + AMB) built with poly(lactide-co-glycolide) (PLGA) 50:50 using the preformed polymer interfacial deposition method were developed at a 0.05 mg mL- 1 theoretical concentration to improve antifungal activity with two actives association and assistance from PDTa. It showed an average particle diameter of 253.8 ±â€¯17.3, an average polydispersity index of 0.36 ±â€¯0.01, and a negative Zeta potential average of -31.03 ±â€¯5.54 for 158 days. UV-vis absorption and emission spectroscopy analyses did not show changes in photophysical properties in the steady-state of NC/ZnS4Pc + AMB counterparts free ZnS4Pc. The encapsulation percentage of actives was 89.24 % and 7.40 % for ZnS4Pc and AMB, respectively. Cell viability assay using NIH/3T3 ATCC® CRL-1658 ™ cells line showed no cytotoxicity for the concentrations tested. The photodynamic activity assay using NC/ZnS4Pc + AMB diluted showed fungal toxicity against Candida albicans yeast with energetic fluences of 12 J.cm-2 and 25 J.cm-2 by a decrease in cell viability. The MFC assay demonstrated a fungistatic activity for the conditions employed in the PDTa assay. The results show that NC/ZnS4Pc + AMB is a promising nanomaterial for antimicrobial inactivation using PDT.

Anthraquinone encapsulation into polymeric nanocapsules as a new drug from biotechnological origin designed for photodynamic therapy.

Photodynamic therapy has been applied for the treatment of many diseases, especially skin diseases. However, poor aqueous solubility and toxicity of some photosensitizer drugs are the main disadvantages for their direct clinical applications. Thus, biotechnology and nanotechnology are important tools in the development of new ways of obtaining photoactive compounds that are biocompatible. We investigated the potential of a new nanostructured photosensitizer, an anthraquinone derivative produced by biotechnological process; then we associated nanotechnology to obtain a nanostructured anthraquinone active molecule. For this, it was prepared a classical nanocapsule formulations containing poly(lactide-co-glycolide) (PLGA) coating for encapsulation of anthraquinone derivative. These formulations were characterized by their physicochemical, morphological, photophysical properties, and stability. We performed in vitro biocompatibility and photodynamic activity assays of free and nanostructured anthraquinone. Nanocapsule formulations containing anthraquinone derivative showed a nanometric profile with particle size around 250 nm, negative zeta potential around -30 mV, and partially monodisperse. Besides that, characteristic spherical morphology of nanocapsules and homogeneous particle surface were observed by AFM analyses. The in vitro biocompatibility assay showed absence of cytotoxicity for all tested RD/NC concentrations and also for unloaded/NC in NIH3T3 cells. In vitro photoactivation assay using NIH3T3 cells showed that nanocapsules promoted greater drug uptake by NIH3T3 cells, around of 87%, of cell death compared to free drug showed around 48% of cell death. The anthraquinone derivative showed potential for use in PDT. Besides the association with nanocapsules improved cell uptake of photosensitizer resulting in increased cell death compared to free anthraquinone.

In vitro effects of photodynamic therapy induced by chloroaluminum phthalocyanine nanoemulsion.

BACKGROUND: The photodynamic therapy (PDT) has been used to treat cancer mainly by inducing oxidative stress. Our aim was to evaluate the effect of PDT and its combination with methoxyamine (MX), a blocker of base excision repair (BER), in cells expressing high levels of the APE1 protein, which is involved in cell oxidative damage response. METHODS: The HeLa and A549 cells were treated for 3h with chloroaluminum phthalocyanine incorporated into a well-designed nanoemulsion (ClAlPc/NE); and then irradiated by visible light (@670nm) with doses of 0.1, 0.5 and 1.0J/cm2. A simultaneous combination of MX+ClAlPc/NE was performed and then irradiated with the selected dose of 0.5J/cm2. The treatments were evaluated in terms of viability, clonogenicity, DNA fragmentation, and cell death mechanism by apoptosis and/or necrosis. RESULTS: The APE1 protein expression observed was higher in HeLa than in A549. Both cell lines exhibited substantial differences in cell cytotoxicity. The PDT decreased the clonogenicity of HeLa by inducing apoptosis (sub-G1 and annexin detection). Additionaly, the MX potentiates the PDT-effects in HeLa. Otherwise, low cytotoxicity was observed in A549 cells. CONCLUSION: The PDT induced apoptosis in high APE1 expressive HeLa cells, and the blockage of BER by MX increased its effects.