Principales propiedades inmunomoduladoras y antinflamatorias de la ficobiliproteína C-ficocianina / Main immunomodulatory and anti-inflamatory properties of phycobiliproteins C-phycocyanin

Las ficobiliproteínas son proteínas solubles en agua, que funcionan como pigmentos fotosintéticos accesorios en diferentes organismos tales como las cianobacterias, las algas rojas y las criptomonadas. En el alga verdeazul Spirulina platensis, una de las ficobiliproteínas más abundantes es la C-ficocianina, la cual tiene unido tres cromóforos ficocianobilina mediante un enlace tioéter a cisteínas específicas. La ficocianobilina es un tetrapirrol lineal asociado a la captación de energía solar en estos organismos. La C-ficocianina ha sido empleada en diferentes investigaciones biomédicas como biomarcador, por sus propiedades fluorescentes, y como posible agente terapéutico para el tratamiento de enfermedades asociadas al estrés oxidativo, por sus propiedades antioxidantes, inmunomoduladoras y antinflamatorias. Se ha demostrado que esta proteína aumenta la liberación de interferón gamma en células mononucleares de sangre periférica y modula la producción de citocinas inflamatorias como el factor de necrosis tumoral alfa, entre otras. Además, se ha encontrado que la C-ficocianina tiene efecto inmunomodulador de citocinas que potencian la activación de las células del sistema inmune, como la IL-6 y la IL-1ß, así como la regulación de aproximadamente 190 genes implicados en la inmunidad(AU)

Phycobiliproteins are water-soluble proteins that function as accessory photosynthetic pigments in different organisms such as cyanobacteria, red algae and cryptomonads. In the blue-green algae Spirulina platensis one of the most abundant phycobiliproteins is the C-phycocyanin, which has three phycocyanobilin chromophores linked through a thioether bond to specific cysteine. The phycocyanobilin is a linear tetrapyrrole associated with solar energy absorption in these organisms. The C-phycocyanin has been used in several biomedical researches as a biomarker, for their fluorescence properties, and as a possible therapeutic agent for the treatment of diseases associated with oxidative stress for its antioxidant, anti-inflammatory and immunomodulatory properties. It has been shown that this protein increases the release of interferon gamma in peripheral blood mononuclear cells, and modulates the production of inflammatory cytokines such as tumor necrosis factor among others. Furthermore it has been found that the C-phycocyanin has immunomodulatory effect on cytokines that enhance the activation of immune cells, such as IL-6 and IL-1ß, and the regulation of about 190 genes involved in immunity(AU)

Photodynamic DNA damage induced by phycocyanin and its repair in Saccharomyces cerevisiae

In the present study, we analyzed DNA damage induced by phycocyanin (PHY) in the presence of visible light (VL) using a set of repair endonucleases purified from Escherichia coli. We demonstrated that the profile of DNA damage induced by PHY is clearly different from that induced by molecules that exert deleterious effects on DNA involving solely singlet oxygen as reactive species. Most of PHY-induced lesions are single strand breaks and, to a lesser extent, base oxidized sites, which are recognized by Nth, Nfo and Fpg enzymes. High pressure liquid chromatography coupled to electrochemical detection revealed that PHY photosensitization did not induce 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo) at detectable levels. DNA repair after PHY photosensitization was also investigated. Plasmid DNA damaged by PHY photosensitization was used to transform a series of Saccharomyces cerevisiae DNA repair mutants. The results revealed that plasmid survival was greatly reduced in rad14 mutants, while the ogg1 mutation did not modify the plasmid survival when compared to that in the wild type. Furthermore, plasmid survival in the ogg1 rad14 double mutant was not different from that in the rad14 single mutant. The results reported here indicate that lethal lesions induced by PHY plus VL are repaired differently by prokaryotic and eukaryotic cells. Morever, nucleotide excision repair seems to play a major role in the recognition and repair of these lesions in Saccharomyces cerevisiae