Recently, recruitment of newborn astrocytes and neurons from the SVZ
was shown to play an important role following ischemic injury and stroke [130,131].
Within the authors' explanations for the discrepancies between these human SVZ
studies, it became clear that consent about the optimal methodology concerning tissue sampling, anatomical definition of sampling area, choice of markers for SVZ
stem and progenitor cells, and quantification still needs to be defined [49, 50].
The anterior pituitary hormone prolactin (PRL) has been identified as one of the main endogenous cues promoting proliferation of SVZ
progenitors in the reproductive context [26-28, 32, 46], suggesting a cooperation between hormones and brain plasticity to generate proper physiological and behavioral responses to the external stimuli .
found that Nestin-stained or BrdU-labeled cells were mainly located in the basal ganglion and nearby SVZ
around hematoma and ependyma after ICH in rats.
Hence, cell proliferation in the SVZ
has been shown to be increased on PD7 in mice, but not at later time points during pregnancy (i.e., PD14 and PD21) [115, 116], whereas in rats the complete opposite picture occurred .
Histological staining from mouse brain sections indicates high level of CXCR4 expression in SGZ and SVZ
implicating that the SDF-1/CXCR4 signaling pathway may be involved in NSCs/NPCs regulation [16-18].
The adult mammalian brain contains a population of NSCs in the subventricular zone (SVZ
) of the lateral ventricle that migrates to the olfactory bulb and generates new neurons [49, 50] and the subgranular zone (SGZ) of the hippocampal dentate gyrus (DG) [51, 52].
Regarding PD, stem cells and related cellular plasticity markers are also altered in relevant animal models [24-26], but only few studies exist on proliferative changes in human PD brain , most of which have focused on the SN [27, 28] and subventricular zone (SVZ
) [29, 30].
Endogenous neural stem and progenitor cells (NSPCs), also described in this review as neural stem cells (NSCs), persist in the subventricular zone (SVZ
) lining the ventricles and the subgranular zone (SGZ) of the hippocampus in the adult brain.
Since then, several studies have established that newborn neurons in the dentate gyrus are required for mediating some of the beneficial effects of antidepressant treatments since the increase in cell proliferation after antidepressant treatment is only observed in the SGZ and not in SVZ
, suggesting a specificity of the antidepressants to regulate hippocampal neurogenesis.