Evaluation of the activity of the immune system and age-related tissue markers in Turquoise killifish (Nothobranchius furzeri, Jubb 1971) and their role in cell ageing

Currently the Turquoise Killifish is considered the best animal model suitable for aging research. This annual fish, from south east Africa, shows an exceptionally adaptive behaviour to dry periods: indeed, due to this extreme environmental characteristics, the life cycle of Nothobranchius furzeri is very fast, with an average lifespan of just about 8-9 weeks, making this species (more similar to highly developed vertebrates than nematodes or fruit flies) highly practical for aging studies. The present study has evaluated the activity of the immune system as well as the expression of AGE-RAGE system, cell-damage related proteins (Bcl2, p53), mitosis activity marker (PCNA), and pro-apoptosis activity by T.U.N.E.L. method on the liver of four lifespan-specific strains of Turquoise Killifish (Nothobranchius furzeri, Jubb 1971), correlating the results with aging processes and tumor incidence. Some groups underwent caloric restriction(definition) in order to module their expected lifespan. The results demonstrated an increase of age-related lesions along with the age in all the strains tested, due to a decrease of cellular-turn-over. This aspect was also influenced by the strain of the fish: longest lifespan strains showed later the similar lesions than short lifespan strains. Moreover caloric restriction groups showed lower incidence and severity of hepatic degeneration than control groups. Furthermore, there was a linear correspondence between the age of the model and its expected lifespan with the incidence and severity of neoplasm. The same relationship could be found in the expression of cell-damage related proteins (p53, Bcl2), age-related markers (AGE-RAGE system) and pro-apoptosis activity, as well as in the development of neoplasms. These results demonstrated the high feasibility of this fish as an excellent model to study the effects of aging processes and cancer genesis.