The Zebrafish Embryo as a Model to Test Protective Effects of Food Antioxidant Compounds.

The antioxidant activity of food compounds is one of the properties generating the most interest, due to its health benefits and correlation with the prevention of chronic disease. This activity is usually measured using in vitro assays, which cannot predict in vivo effects or mechanisms of action. The objective of this study was to evaluate the in vivo protective effects of six phenolic compounds (naringenin, apigenin, rutin, oleuropein, chlorogenic acid, and curcumin) and three carotenoids (lycopene B, ß-carotene, and astaxanthin) naturally present in foods using a zebrafish embryo model. The zebrafish embryo was pretreated with each of the nine antioxidant compounds and then exposed to tert-butyl hydroperoxide (tBOOH), a known inducer of oxidative stress in zebrafish. Significant differences were determined by comparing the concentration-response of the tBOOH induced lethality and dysmorphogenesis against the pretreated embryos with the antioxidant compounds. A protective effect of each compound, except ß-carotene, against oxidative-stress-induced lethality was found. Furthermore, apigenin, rutin, and curcumin also showed protective effects against dysmorphogenesis. On the other hand, ß-carotene exhibited increased lethality and dysmorphogenesis compared to the tBOOH treatment alone.

Genética del hipotiroidismo congénito / The genetics of congenital hypothyroidism

Se realizó una revisión narrativa sobre la genética del hipotiroidismo congénito (HC). Se utilizaron las bases de datos Medline/PubMed, LILACS-BIREME y SciELO. Se identificaron los estudios originales publicados entre 2000 y agosto de 2020. Las palabras clave utilizadas durante la búsqueda fueron las siguientes: "hipotiroidismo congénito (congenital hypothyroidism)", "genética (genetic)", "polimorfismos de nucleótido único (SNP) (single polymorphisms nucleotid)". Se revisaron 58 estudios originales que informan las bases moleculares del HC. Se ha definido el concepto básico del HC, así como las bases moleculares que están asociados con la aparición de dicho trastorno. La revisión de la literatura ha permitido identificar al menos 12 genes que codifican las proteínas, las cuales, al producirse mutaciones, están implicadas en el HC. De los 12 genes informados que desempeñan un papel importante en el HC, errores en 6 genes se han vinculado con el HC con disgenesia tiroidea, lo cual implica alteraciones en la morfogénesis de la glándula tiroides, mientras que mutaciones en otros 6 genes se han asociado con dishormonogénesis, que genera un bloqueo total o parcial de los procesos bioquímicos implicados en la síntesis y secreción de hormonas tiroideas. La prevalencia en Sudamérica varía aproximadamente desde 1 por cada 1170 hasta 1 por cada 8285 neonatos. El estudio de la genética molecular pone de manifiesto que, en el futuro, aportará datos importantes en cuanto a la identificación de nuevas mutaciones y asociaciones con fenotipos clínicos que podrían relacionarse con el HC, para, de esta manera, potenciar el diagnóstico y tratamiento

A narrative review was conducted on the genetics of congenital hypothyroidism. The Medline/PubMed, LILACS-BIREME, and SciELO databases were used. Original studies published between 2000 and August 2020 were identified. The keywords used during the search were as follows: "congenital hypothyroidism", "genetics", "polymorphisms SNPs". Fifty-eight original studies reviewing the molecular basis of congenital hypothyroidism were reviewed. The basic concept of congenital hypothyroidism has been defined as well as the molecular bases that are associated with the development of this disorder. The literature review has identified at least 12 genes encoding proteins that, when mutations occur, are involved in congenital hypothyroidism. Of the 12 genes reported to play an important role in congenital hypothyroidism, errors in 6 genes have been associated with congenital hypothyroidism with thyroid dysgenesis, which implies alterations in the morphogenesis of the thyroid gland. On the other hand, mutations in 6 other genes have been associated with dyshormonogenesis that generates a total or partial blockage of the biochemical processes involved in the synthesis and secretion of thyroid hormones. The prevalence in South America is reported to vary from approximately 1 per 1000 to 1 per 8000 newborns. The study of molecular genetics shows that in the future it will contribute to the identification of new mutations and associations with clinical phenotypes that could be related to congenital hypothyroidism, thus enhancing diagnosis and treatment