Bioengineered sequential growth factor delivery stimulates brain tissue regeneration after stroke

Nanomedicine Approaches to Modulate Neural Stem Cells in Brain Repair

“…The role of NP was to control the release of bioactive agents within the gel without any targeting role to the stem cell population. The sequential release of both molecules regenerated the peri-infarct region, which was correlated with an increase in SVZ NSC proliferation [7]. This biomaterial approach may be an alternative to intracerebroventricular infusion by a catheter/minipump system, as demonstrated in preclinical tests.…”

Drug delivery: Brain food

“…She then added a layer of polysebacic acid to the erythropoietin bundle so that the drug would not be released at the same time as the endothelial growth factor. Then she suspended the beads in the hydrogel 6 . With the challenge of developing a gel behind them, she moved on to test it in a mouse model of stroke.…”

“…It worked: the brains had smaller areas of dead tissue, more living neurons in the damaged area and less inflammation compared with mice that received the growth factors through the cannula 6 . And because the 4-day delay meant that very few cells were still alive, the living neurons the researchers saw in the brains were likely to be new cells rather than repaired ones.…”

Dynamic and Responsive Growth Factor Delivery from Electrospun and Hydrogel Tissue Engineering Materials

“…[12] Furthermore, in neuroscience applications epidermal growth factor (EGF), which increases proliferation of neural stem/ progenitor cells (NSPCs), is best delivered initially for 7 d, followed by erythroprotein (EPO) to protect and reduce apoptosis in the new cells. [13] In addition to the order of delivery, different growth factors require different durations. The demyelination process, for example, involves many growth factors with different temporal presentation profiles in the cortex, including initial presentation lasting 2 weeks for glial cell line derived neurotrophic factor (GDNF), initial sustained presentation for FGF-2, and delayed presentation starting after 1 week for transforming growth factor beta-1 (TGF-β1).…”

“…[22] Sustained and controlled delivery to the brain can be achieved using intracerebroventricular infusion or micropumps; however, this is very invasive and causes significant tissue damage so much research has focused on using tissue engineering scaffolds as growth factor delivery vehicles as well. [13,24] Tissue engineering materials can be used as a reservoir for sustained and controlled drug delivery as in many instances they are engineered to be minimally invasive (i.e., shear thinning hydrogels) and their inherent biocompatibility means that they can be implanted for long durations. Note that when using a reservoir, temporally controlled delivery must be achieved via controlled delay in release from the reservoir.…”