Adult neurogenesis in the brain of the Mozambique tilapia, Oreochromis mossambicus

Magda C Teles,Günther K H Zupanc,Rui F Oliveira,Ursula M Wellbrock,Ruxandra F Sîrbulescu

doi:10.1007/s00359-012-0721-6

Abstract

Although the generation of new neurons in the adult nervous system ('adult neurogenesis') has been studied intensively in recent years, little is known about this phenomenon in non-mammalian vertebrates. Here, we examined the generation, migration, and differentiation of new neurons and glial cells in the Mozambique tilapia (Oreochromis mossambicus), a representative of one of the largest vertebrate taxonomic orders, the perciform fish. The vast majority of new cells in the brain are born in specific proliferation zones of the olfactory bulb; the dorsal and ventral telencephalon; the periventricular nucleus of the posterior tuberculum, optic tectum, and nucleus recessi lateralis of the diencephalon; and the valvula cerebelli, corpus cerebelli, and lobus caudalis of the cerebellum. As shown in the olfactory bulb and the lateral part of the valvula cerebelli, some of the young cells migrate from their site of origin to specific target areas. Labeling of mitotic cells with the thymidine analog 5-bromo-2'-deoxyuridine, combined with immunostaining against the neuron-specific marker protein Hu or against the astroglial marker glial fibrillary acidic protein demonstrated differentiation of the adult-born cells into both neurons and glia. Taken together, the present investigation supports the hypothesis that adult neurogenesis is an evolutionarily conserved vertebrate trait.

Highlights

Invasive species are a worldwide leading threat to wildlife conservation (Vitousek et al 1997; Molnar et al 2008)
In agreement with the existing literature (Mathieu et al 2002; Pirone et al 2008) neuropeptide Y (NPY)-ir cells were regionally located in discrete nuclei while a wide presence of positive fibers was seen throughout the brain, except the cerebellum
Some NPY-ir cells are found in the posterior part of the preoptic area, in the hypothalamus, in the nucleus posterioris periventricularis (Npp) (Figs. 2h, 4)

Summary

Introduction

Invasive species are a worldwide leading threat to wildlife conservation (Vitousek et al 1997; Molnar et al 2008). The invasive alga Caulerpa cylindracea showed an explosive dispersal and had a deep impact on indigenous communities in the Mediterranean Basin (Piazzi and Cinelli 2001; Piazzi and Balata 2008; Deudero et al 2011; VázquezLuis et al 2009). This impact includes the secondary effects of the ingestion of metabolites present in the alga tissue (Felline et al 2017) that become a major diet component of white sea bream, Diplodus sargus (Klein and Verlaque 2008; Box et al 2009; Terlizzi et al 2011). Neuropeptide Y (NPY) is a highly conserved neuropeptide that, beside to have orexigenic effect (reviewed in Loh et al 2015), it shows anxiolytic and stressreducing properties (reviewed in Karl and Herzog 2007; Schmeltzer et al 2016), decreasing swimming activity in fish (Matsuda et al 2011, 2012; Jeong et al 2018).

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Results

Conclusion