Contribution of brain pericytes to neuroinflammation following repetitive head trauma.

Background: Neuroinflammation is a prominent pathological hallmark of traumatic brain injury (TBI) and glia cells have been widely characterized in the onset or progression of brain inflammation. While an effect of inflammation on cerebrovascular breakdown has been observed, little is known about the specific contribution of brain pericytes to the inflammatory response in TBI. Here, we focused on studying the pericyte response to inflammatory stimuli commonly found in the brain following TBI.

Repetitive head trauma and apoE4 induce chronic cerebrovascular alterations that impair tau elimination from the brain.

Repetitive mild traumatic brain injuries (r-mTBI) sustained in the military or contact sports have been associated with the accumulation of extracellular tau in the brain, which may contribute to the pathogenesis of neurodegenerative tauopathies. The expression of the apolipoprotein E4 (apoE4) isoform has been associated with higher levels of tau in the brain, and worse clinical outcomes after r-mTBI, though the influence of apoE genotype on extracellular tau dynamics in the brain is poorly understood. We recently demonstrated that extracellular tau can be eliminated across blood-brain barrier (BBB), which is progressively impaired following r-mTBI.

Biomimetic Materials and Their Utility in Modeling the 3-Dimensional Neural Environment.

The brain is a complex 3-dimensional structure, the organization of which provides a local environment that directly influences the survival, proliferation, differentiation, migration, and plasticity of neurons. To probe the effects of damage and disease on these cells, a synthetic environment is needed. Three-dimensional culturing of stem cells, neural progenitors, and neurons within fabricated biomaterials has demonstrated superior biomimetic properties over conventional 2-dimensional cultureware, offering direct recapitulation of both cell-cell and cell-extracellular matrix interactions.

Engineering of Chitosan-Hydroxyapatite-Magnetite Hierarchical Scaffolds for Guided Bone Growth.

Bioabsorbable materials have received increasing attention as innovative systems for the development of osteoconductive biomaterials for bone tissue engineering. In this paper, chitosan-based composites were synthesized adding hydroxyapatite and/or magnetite in a chitosan matrix by in situ precipitation technique. Composites were characterized by optical and electron microscopy, thermogravimetric analyses (TGA), x-ray diffraction (XRD), and in vitro cell culture studies.