Nerve Growth Factor in the adult brain of a teleostean model for ageing research: Nothobranchius furzeri

Nerve growth factor (NGF) is a pluripotent mediator, originally considered important in neuronal homeostasis and pathophysiology, later it was also implicated in the ageing processes. In mammals, NGF is viewed as im-portant for the survival of forebrain cholinergic neurons, involved in cognitive function, and appears to degen-erate with age and markedly diminish in Alzheimer’s disease. The age-related decrease of NGF occurs particu-larly in memory-linked areas such as the hippocampus. Also in non mammalian vertebrate models, NGF changes in age-related degeneration and increases in various pathological lesions. This study analyzes the localization of NGF in the brain of N. furzeri, a model for ageing research. Experiments of in situ hybridization (ISH), by using a LNA probe, and immunohistochemistry (IHC), by employing an antibody mapping at the N-terminus of the mature chain of NGF of human origin, were performed. NGF mRNA expression was observed in the neuronal perikarya of all major regions of the brain, with the highest rate of signal probe in the telen-cephalon (mainly in the subpallial telencephalon). The protein was detected in the cytoplasm of neurons and, to a less extent, in fibers, both diffused throughout the telencephalon, diencephalon, mesencephalon and rhomboencephalon. The widespread distribution of NGF mRNA and protein suggests that the NGF system may modulate numerous physiological functions also in the adult brain of fish. The present survey constitutes a baseline study to enhance the understanding of the mechanisms underlying the role of NGF during ageing processes.