IMBIV   05474
INSTITUTO MULTIDISCIPLINARIO DE BIOLOGIA VEGETAL
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Search for bioactive components from Argentine native species with influence on melanogenesis related enzymes?
Autor/es:
SANTI, M.DANIELA; ORTEGA, MARÍA GABRIELA
Lugar:
Montevideo
Reunión:
Simposio; Symposium on Molecular and Cell Biology to unravel the Physiology/Pathology of diverse Biological Paradigms; 2015
Institución organizadora:
Instituto de Investigaciones Biológicas Clemente Estable
Resumen:
Tyrosinase, a copper-containing monooxygenase, is involved in melanin biosynthesis and catalyzes two different reactions in the melanin synthesis: formation of3,4-dihydroxyphenylalanine (DOPA) by hydroxylation of L-tyrosine (monophenolase activity) and the subsequent dopaquinone formation (diphenolase activity). The spontaneous polymerization of dopaquinone conduces to form several brown or black pigments such as melanin, the present pigment in mammals and responsible for the colour of skin, eyes and hair pigmentation. Melanin protects the skin from the harmful effects of ultraviolet (UV) that penetrate the skin and prevents the consequent damage of DNA. But, there are physiological and/or pathological conditions that can alter the normal functioning of the melanin:Melanin hyperpigmentation affects the skin producing age spots, melasma and malignant melanoma (1,2). For these reason, tyrosinase inhibitors are an alternative for these undesirable conditions. Kojic acid and hydroquinone are currently commercialized as withening agents, however both have numerous adverse effects, such as genotoxic effects, allergic dermatitis, permanent depigmentation, respectively. flavonoids from Licorice roots, glabrene (isoflavene) and isoliquiritigenin (chalcone), were also found to be strong tyrosinase inhibitors (5).Furthermore, stimulators tyrosinase compounds could be important for different hypopigmentation disorders (3). As potential candidates, naturally occurring flavonoids have been examined. Compounds such as apigenin and icariin , both flavones have been reported as melanogenesis stimulators. From Dalea boliviana, a species studied in our group, were obtained new prenylated flavanones such as (2S) - 5, 7,2 ′ - trihydroxy-8,3 ′-diprenyl-flavanone and (2S)-5,7,2′-trihydroxy-8-prenyl-5´- (1 ´´´,1 ´´´-dimethylallyl)?8 prenylflavanone and were reported as tyrosinase mushroom inhibitors(4).For the foregoing, it is necessary the investigation of novel natural compounds, which affect melanin synthesis either its inhibition, in order to obtain components that can be used as bleaching agents and for the treatment of pathologies associated with abnormalities in the skin pigmentation; as in its production since compounds that enhance skin pigmentation would impact not only hypopigmentation diseases, but also in those physiological states associated with aging that causing less melanin, reducing the risk of skin cancer. From D. elegans, three C-methyl flavanones and a methyl chalcone have been isolated from aerial parts of D. elegans and informed for the first time in this species. The tyrosinase inhibition activities of them were investigated. Among these compounds, 1 (8PP) has demonstrated to be a strong inhibitor two times more active than kojic acid. Triangularin (3) also has shown an important inhibitory activity. Their kinetics parameters were studied. So, the results obtained shown the potential of these compounds as promising agents for the treatment in disorders related with abnormal skin pigmentation In this moment, these compound are evaluated as inhibitory/promoter of tyrosinase obtained from cell lines mouse melanoma B16 and their results are in progress.Dalea pazensis showed the presence of 8PP, an important mushroom tyrosinase inhibitor. At the moment other flavonoids are studied in order toelucidate their chemical structures.