RESUMO
The study of digestive physiology is an important issue in species that have been introduced in aquaculture like the spotted rose snapper (Lutjanus guttatus). The aims of this study were to describe the expression of digestive enzymes (trypsinogen, chymotrypsinogen, α-amylase, lipoprotein lipase, phospholipase A and pepsinogen) and their relation with orexigenic (neuropeptide Y, NPY) and anorexigenic (cholecystokinin, CCK) factors during the larval development and to evaluate the effect of weaning in their expression. The results showed that the transcripts of all the assayed digestive enzymes, with the exception of pepsinogen, and NPY and CCK were already present in L. guttatus from the hatching stage. The expression of all the enzymes was low during the yolk-sac stage (0-2 days after hatching, DAH), whereas after the onset of exogenous feeding at 2 DAH, their expression increased and fluctuated throughout larval development, which followed a similar pattern as in other marine fish species and reflected changes in different types of food items and the progressive maturation of the digestive system. On the other hand, weaning of L. guttatus larvae from live prey onto a microdiet between 25 and 35 DAH significantly affected the relative expression of most pancreatic digestive enzymes during the first weaning days, whereas chymotrypsinogen 2 and lipoprotein lipase remained stable during this period. At the end of co-feeding, larvae showed similar levels of gene expression regardless of the diet (live prey vs. microdiet), which indicated that larvae of L. guttatus were able to adapt their digestive capacities to the microdiet. In contrast, feeding L. guttatus larvae with live feed or microdiet did not affect the expression of CCK and NPY. The relevance of these findings with regard to current larval rearing procedures of L. guttatus is discussed.
Assuntos
Digestão/genética , Perciformes/genética , Animais , Colecistocinina/genética , Quimotripsinogênio/genética , Feminino , Expressão Gênica , Larva/genética , Larva/crescimento & desenvolvimento , Lipase Lipoproteica/genética , Masculino , Neuropeptídeo Y/genética , Pepsinogênio A/genética , Perciformes/crescimento & desenvolvimento , Perciformes/metabolismo , Fosfolipases A2/genética , RNA Mensageiro/metabolismo , Tripsinogênio/genética , alfa-Amilases/genéticaRESUMO
The scientific advances related to healthy properties of the probiotics have increased in a significant form. It is evident the positive effects on physiological functions. Considering the relevance in these advances, this review presents a summary of the scientific evidence supporting the principal biological effects of the probiotics in digestive function, systemic immune reply and lipid profile, pathologies relevant in the functional food development.
Los avances científicos en relación a las propiedades saludables de los probióticos han aumentado significativamente, mostrando grandes avances en su efecto sobre diferentes funciones fisiológicas. Los hallazgos demuestran que las acciones a nivel fisiológico o clínico son cepa específicos, aspecto que toma cada día mayor relevancia en el desarrollo de alimentos funcionales asociados a probióticos. Teniendo en cuenta la importancia de estos avances, este artículo presenta de forma resumida evidencia que sustenta los principales efectos clínicos atribuidos a los probióticos en enfermedades relacionadas con el sistema digestivo, función inmune y metabolismo lipídico, patologías en las cuales el desarrollo de alimentos funcionales se ha venido enfocando.