Neurogenesis in the postnatal cerebellum after injury

Abstract

The cerebellum plays major role in motor coordination and learning. It contains half of the neurons in the brain. Thus, deciphering the mechanisms by which cerebellar neurons are generated is essential to understand the cerebellar functions and the pathologies associated with it. In a recent study, Wojcinski et al. (2017) by using in vivo Cre/loxP technologies reveal that Nestin-expressing progenitors repopulated the external granular cell layer after injury. Depletion of postnatal external granular cell layer is not sufficient to induce motor behavior defects in adults, as the cerebellum recovers these neurons. Strikingly, Nestin-expressing progenitors differentiate into granule cell precursors and mature granule neurons after ablation of perinatal external granular layer, either by irradiation or by genetic ablation. This work identified a novel role of Nestin-expressing progenitors in the cerebellar microenvironment during development, and revealed that extracellular signals can convert specified progenitors into multipotent stem cells. Here, we discuss the findings from this study, and evaluate recent advances in our understanding of the cerebellar neurogenesis.

Pericyte Plasticity in the Brain

“…In the last decade, the potential of pericytes to contribute to tissue regeneration/homeostasis as tissue-resident progenitors has been established by numerous studies [74][75][76]. Pericytes not only participate in the formation of new blood vessels [53], but their ability to differentiate into the neural lineage has also been demonstrated [48,[77][78][79][80][81][82][83]. Therefore, pericytes are expected to be able to proliferate and multiply when activated.…”

Macrophage‐derived GPNMB accelerates skin healing

“…The use of typical knockout mice models has proved useful in understanding the role of key molecules in physiological and pathological conditions . Nonetheless, these technologies have their limitations.…”

Role of Schwann cells in cutaneous wound healing

“…The decisions of stem cells to continue quiescent, self‐renew, or differentiate are dependent on the interaction of these cells with other cells in their surrounding niches . Recently, multiple cell types have been identified as potential niche‐supporting cells for stem cells in the skin .…”

“…The decisions of stem cells to continue quiescent, selfrenew, or differentiate are dependent on the interaction of these cells with other cells in their surrounding niches. [60][61][62][63][64][65][66][67][68] Recently, multiple cell types have been identified as potential niche-supporting cells for stem cells in the skin. 69 Nevertheless, how the composition of the cutaneous stem cell niche is affected during skin healing remains poorly understood.…”