Cerebellum developmental challenges: From morphology to molecular issues

Abstract

Introduction: It is known that, throughout the development of the nervous system, the cellular migratory routes are an important part of its expansion; therefore, the cerebellum is ‘sprinkled’ with cellular changes during its growth. The aim of this study was to analyse the morphological features of the cerebellum cells in all the layers, during its development. Material and methods: We examined 14 cases of human cerebellum, ranging between 1 to 12 months by histopathology and immunohistochemistry. Results: Haematoxylin and eosin staining method confirmed the age-linked migration of the cells from the external granular layer into the internal granular layer. Moreover, immunohistochemical evaluation using PROX1 and NFAP showed positivity for the Purkinje cells. However, these cells exposed negativity on NSE stained specimens. On the other hand, the transience of the EGL was analyzed using OCT3/4, which showed the migration of the EGL cells through the molecular layer to the IGL. Also, GFAP and NFAP proved to be a useful tool for the identification of the climbing fibres and the variation of their density connected the age of the patient. Conclusions: The human cerebellum undergoes different morphological and molecular changes throughout its evolution during embryogenesis. The markers used in our study have proved to present a differential, stage-dependant reactivity and appeared as useful tools for the identification of different cerebellar structures. Our study is a challenging attempt to understand the basics of cerebellar development at a morphological and molecular level and may bring new perspectives for a better approach of cerebellar associated pathologies.

Keywords

• human cerebellum
• external granular layer (EGL)
• internal granular layer (IGL
• embryogenesis
• developmental changes.