Research on the Interaction between Pheophorbide and Bovine Serum Albumin

One ring is not enough to rule them all. Albumin-dependent ABCG2-mediated transport of chlorophyll-derived photosensitizers

Breast cancer resistance protein (BCRP, ABCG2) is a member of the ATP-binding-cassette (ABC) superfamily of membrane transporters. It is involved in the efflux of a broad range of xenobiotics of highly diverse structures. BCRP activity greatly influences drug distribution in vivo and is often associated with cancer multidrug resistance, which is observed in the case of both chemotherapy and photodynamic therapy. The set of ABCG2 substrates includes porphyrins and chlorins such as heme, hemin, protoporphyrin IX, chlorin e6, pheophorbide a, and their derivatives. Here we provide an evidence that magnesium- and zinc-substituted derivatives of pheophorbide a, which are very promising photosensitizers for use in photodynamic therapy, are also recognized and transported by ABCG2. Interestingly, despite minor structural differences, they clearly differ in the transport rate, both between each other and compared to pheophorbide a. In addition, their transport rate, like those of other structurally similar compounds, is strictly dependent on the level of serum albumin in the extracellular environment. The results that we present here are crucial for the use of metal-substituted pheophorbides in clinical practice but also provide an important insight into the mechanism of porphyrin transport by ABCG2.

The Bio-Safety Concerns of Three Domestic Temporary Hair Dye Molecules: Fuchsin Basic, Victoria Blue B and Basic Red 2

Hair-coloring products include permanent, semi-permanent and temporary dyes that vary by chemical formulation and are distinguished mainly by how long they last. Domestic temporary hair dyes, such as fuchsin basic, basic red 2 and Victoria blue B, are especially popular because of their cheapness and facile applications. Despite numerous studies on the relationship between permanent hair dyes and disease, there are few studies addressing whether these domestic temporary hair dyes are associated with an increased cancer risk. Herein, to ascertain the bio-safety of these temporary hair dyes, we comparatively studied their percutaneous absorption, hemolytic effect and cytotoxic effects in this paper. Furthermore, to better understand the risk of these dyes after penetrating the skin, experimental and theoretical studies were carried out examining the interactions between the dyes and serum albumins as well as calf thymus (CT)-DNA. The results showed that these domestic temporary hair dyes are cytotoxic with regard to human red blood cells and NIH/3T3 cell lines, due to intense interactions with bovine serum albumin (BSA)/DNA. We conclude that the temporary hair dyes may have risk to human health, and those who use them should be aware of their potential toxic effects.

Daunomycin-loaded superparamagnetic iron oxide nanoparticles: Preparation, magnetic targeting, cell cytotoxicity, and protein delivery research

The clinical use of daunomycin is restricted by dose-dependent toxicity and low specificity against cancer cells. In the present study, modified superparamagnetic iron oxide nanoparticles were employed to load daunomycin and the drug-loaded nanospheres exhibited satisfactory size and smart pH-responsive release. The cellular uptake efficiency, targeted cell accumulation, and cell cytotoxicity experimental results proved that the superparamagnetic iron oxide nanoparticle-loading process brings high drug targeting without decreasing the cytotoxicity of daunomycin. Moreover, a new concern for the evaluation of nanophase drug delivery's effects was considered, with monitoring the interactions between human serum albumin and the drug-loaded nanospheres. Results from the multispectroscopic techniques and molecular modeling calculation elucidate that the drug delivery has detectable deleterious effects on the frame conformation of protein, which may affect its physiological function.

Cationic porphyrin@SPION nanospheres as multifunctional anticancer therapeutics: magnetic targeting, photodynamic potential and bio-safety research

Porphyrin@SPION nanospheres are described as pH-controllable, multifunctional photosensitizations with delivery bio-safety.