Hyaluronic Acid-based Scaffolds for Brain Tissue Engineering - Hyaluronic Acid for Biomedical and Pharmaceutical Applications - page 120

have drawn more and more attention [7-9]. Among them, hyaluronic
acid (HA), one of the main components of the extracellular matrix in
brain tissue, is one of the best candidates for brain tissue engineering
because of its good biocompatibility and the ease for chemical
modifications [6, 10]. In this chapter, we outline the progress which has
been made in using HA-based scaffolds for brain regeneration.
6.2 Overview of the Brain and Brain Injury
The brain, one of the most important and complex organs in the
human body, serves as the control centre of the nervous system
that dominates every part of our bodies and controls almost all the
activities, from breathing, hearing and smelling to thinking and
memorising. Damages to the brain tissue, which are mostly caused
by trauma, stroke, tumour and other diseases, usually result in
severe neurological impairments with irretrievable nervous system
functional devastation or limitations such as partial sensory loss,
limited mobility, paralysis, and even death. The adult brain has
limited regenerative capacity that has therefore been a long-standing
severe worldwide problem and has attracted extensive attention from
multi-disciplinary scientists.
6.2.1 The Brain: Basic Anatomy, Composition and Function
[11, 12]
The brain, located in the cranial cavity, is made up of three main parts:
cerebrum, cerebellum, and brainstem. The cerebrum is the largest part
of the human mature brain, which comprises left and right cerebral
hemispheres with the corpus callosum between them. The outermost
surface of the cerebral hemispheres is a 2-4 mm thick folded layer,
named the cerebral cortex that is also called grey matter as it consists
of neuronal cell bodies, glial cells, and capillaries showing dark in
colour. By contrast, the underlying tissue in the cerebrum is called
white matter which consists of the white myelinated sheaths of
neuronal axons.