Evaluation of aluminum phthalocyanine chloride and DNA interactions for the design of an advanced drug delivery system in photodynamic therapy.

The aim of this study was to evaluate the interaction of aluminum phthalocyanine chloride (AlClPc) with double-stranded DNA. Absorption and fluorescence spectra, resonance light scattering, and circular dichroism were evaluated in water and water/ethanol mixtures with different concentrations of DNA or AlClPc. AlClPc showed a high ability to bind to DNA in both water and 4/6 water/ethanol mixture (v/v), with a majority of monomeric and aggregated initial forms of AlClPc, respectively. In this interaction, AlClPc bound preferentially to the grooves of DNA. The monomeric/aggregate state of AlClPc in DNA was dependent on the AlClPc/DNA ratio. At low concentrations of AlClPc, the interaction of AlClPc with few DNA sites caused a curvature in the DNA structure that provided a favorable environment for the intercalation of AlClPc aggregates. Increase in AlClPc concentration induced interactions with a high number of binding sites on DNA, which prevented bending and therefore aggregation of AlClPc molecules throughout the double-stranded DNA. These results are relevant to the understanding of the behavior and interaction of AlClPc with double-stranded DNA in the design of novel drug delivery systems for clinical application in photodynamic therapy as a new approach to treat skin or oral cancer, scars, or wound healing.

Evaluation of antinociceptive and anti-inflammatory activities of the topical preparation of Cipura paludosa (Iridaceae) / Avaliação das atividades antinociceptiva e anti-inflamatória de preparação tópica de Cipura paludosa (Iridaceae)

Alho do mato (Cipura paludosa, Iridaceae) is a medicinal plant found in the Amazon rain forest, North of Brazil. It has been used to treat algic, inflammatory and infectious processes. The aim of this study was to evaluate the anti-inflammatory and antinociceptive action of the crude Cipura paludosa ethanolic extract at concentrations ranging between 2.0 and 4.0% in Oil and Water cream formulations for topical use. The physical-chemical stability of the formulations was monitored over a six-month period with the use of accelerated stability tests. In order to evaluate the anti-inflammatory and antinociceptive activities, we used a paw edema test induced by carrageenan and a formalin test, respectively. The paw edema test showed that there was a statistical difference in the control group in relation to the treatments. The formalin test did not confirm antinociceptive action of the treatments with the extract in the early phase of the test. However, statistical difference was confirmed for the treatments in relation to the control in the late phase. The antinociceptive and anti-inflammatory activities of Cipura paludosa preparations, as demonstrated in the results, at least partially support the ethno-medical uses of this plant.

Allho do mato (Cipura paludosa, Iridaceae) é uma planta medicinal encontrada na floresta Amazônica, norte do Brasil. Essa planta tem sido usada para tratar dores, processos inflamatórios e infecciosos. O objetivo do estudo foi avaliar a ação anti-inflamatória e antinociceptiva do extrato bruto etanólico de Cipura paludosa, nas concentrações que variaram entre 2,0 e 4,0%, em formulações de cremes óleo e água de uso tópico. A estabilidade físico-química das formulações foi monitorada ao longo de um período de seis meses, com a aplicação de ensaios de estabilidade acelerada. A fim de avaliar as atividades anti-inflamatória e antinociceptiva, utilizou-se um teste de edema de pata induzido por carragenina e um teste de formalina, respectivamente. O teste de edema de pata mostrou que houve uma diferença significativa no grupo controle em relação aos tratamentos. O teste da formalina não confirmou efeito antinociceptivo dos tratamentos com o extrato, na primeira fase do ensaio. No entanto, a diferença estatística foi confirmada para os tratamentos em relação ao controle na segunda fase. As atividades antinociceptiva e anti-inflamatória das preparações com Cipura paludosa confirmam de forma parcial o uso etno-médico desta planta.